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  1. Treatment Resistance Mechanisms of Malignant Glioma Tumor Stem Cells

    International Nuclear Information System (INIS)

    Schmalz, Philip G.R.; Shen, Michael J.; Park, John K.

    2011-01-01

    Malignant gliomas are highly lethal because of their resistance to conventional treatments. Recent evidence suggests that a minor subpopulation of cells with stem cell properties reside within these tumors. These tumor stem cells are more resistant to radiation and chemotherapies than their counterpart differentiated tumor cells and may underlie the persistence and recurrence of tumors following treatment. The various mechanisms by which tumor stem cells avoid or repair the damaging effects of cancer therapies are discussed

  2. Radiation induction of drug resistance in RIF-1 tumors and tumor cells

    International Nuclear Information System (INIS)

    Hopwood, L.E.; Moulder, J.E.

    1989-01-01

    The RIF-1 tumor cell line contains a small number of cells (1-20 per 10(6) cells) that are resistant to various single antineoplastic drugs, including 5-fluorouracil (5FU), methotrexate (MTX), and adriamycin (ADR). For 5FU the frequency of drug resistance is lower for tumor-derived cells than for cells from cell culture; for MTX the reverse is true, and for ADR there is no difference. In vitro irradiation at 5 Gy significantly increased the frequency of drug-resistant cells for 5FU, MTX, and ADR. In vivo irradiation at 3 Gy significantly increased the frequency of drug-resistant cells for 5FU and MTX, but not for ADR. The absolute risk for in vitro induction of MTX, 5FU, and ADR resistance, and for in vivo induction of 5FU resistance, was 1-3 per 10(6) cells per Gy; but the absolute risk for in vivo induction of MTX resistance was 54 per 10(6) cells per Gy. The frequency of drug-resistant cells among individual untreated tumors was highly variable; among individual irradiated tumors the frequency of drug-resistant cells was significantly less variable. These studies provide supporting data for models of the development of tumor drug resistance, and imply that some of the drug resistance seen when chemotherapy follows radiotherapy may be due to radiation-induced drug resistance

  3. Autophagy contributes to resistance of tumor cells to ionizing radiation.

    Science.gov (United States)

    Chaachouay, Hassan; Ohneseit, Petra; Toulany, Mahmoud; Kehlbach, Rainer; Multhoff, Gabriele; Rodemann, H Peter

    2011-06-01

    Autophagy signaling is a novel important target to improve anticancer therapy. To study the role of autophagy on resistance of tumor cells to ionizing radiation (IR), breast cancer cell lines differing in their intrinsic radiosensitivity were used. Breast cancer cell lines MDA-MB-231 and HBL-100 were examined with respect to clonogenic cell survival and induction of autophagy after radiation exposure and pharmacological interference of the autophagic process. As marker for autophagy the appearance of LC3-I and LC3-II proteins was analyzed by SDS-PAGE and Western blotting. Formation of autophagic vacuoles was monitored by immunofluorescence staining of LC3. LC3-I and LC3-II formation differs markedly in radioresistant MDA-MB-231 versus radiosensitive HBL-100 cells. Western blot analyses of LC3-II/LC3-I ratio indicated marked induction of autophagy by IR in radioresistant MDA-MB-231 cells, but not in radiosensitive HBL-100 cells. Indirect immunofluorescence analysis of LC3-II positive vacuoles confirmed this differential effect. Pre-treatment with 3-methyladenine (3-MA) antagonized IR-induced autophagy. Likewise, pretreatment of radioresistant MDA-231 cells with autophagy inhibitors 3-MA or chloroquine (CQ) significantly reduced clonogenic survival of irradiated cells. Our data clearly indicate that radioresistant breast tumor cells show a strong post-irradiation induction of autophagy, which thus serves as a protective and pro-survival mechanism in radioresistance. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  4. Heterogeneity in induced thermal resistance of rat tumor cell clones

    International Nuclear Information System (INIS)

    Tomasovic, S.P.; Rosenblatt, P.L.; Heitzman, D.

    1983-01-01

    Four 13762NF rat mammary adenocarcinoma clones were examined for their survival response to heating under conditions that induced transient thermal resistance (thermotolerance). Clones MTC and MTF7 were isolated from the subcutaneous locally growing tumor, whereas clones MTLn2 and MTLn3 were derived from spontaneous lung metastases. There was heterogeneity among these clones in thermotolerance induced by either fractionated 45 0 C or continuous 42 0 C heating, but the order of sensitivity was not necessarily the same. The clones developed thermal resistance at different rates and to different degrees within the same time intervals. There was heterogeneity between clones isolated from within either the primary site or metastatic lesions. However, clones derived from metastatic foci did not intrinsically acquire more or less thermotolerance to fractionated 45 0 C or continuous 42 0 C heating than did clones from the primary tumor. Further, there was no apparent relationship between any phenotypic properties that conferred more or less thermotolerance in vitro and any phenotypic properties that conferred enhanced metastatic success of these same clones by spontaneous (subcutaneous) or experimental (intravenous) routes in vivo. These tumor clones also differ in their karyotype, metastatic potential, cell surface features, sensitivity to x-irradiation and drugs, and ability to repair sublethal radiation damage. These results provide further credence to the concept that inherent heterogeneity within tumors may be as important in therapeutic success as other known modifiers of outcome such as site and treatment heterogeneity

  5. Sensitivity to ionizing radiation and chemotherapeutic agents in gemcitabine-resistant human tumor cell lines

    NARCIS (Netherlands)

    van Bree, Chris; Castro Kreder, Natasja; Loves, Willem J. P.; Franken, Nicolaas A. P.; Peters, Godefridus J.; Haveman, Jaap

    2002-01-01

    Purpose: To determine cross-resistance to anti-tumor treatments in 2',2'difluorodeoxycytidine (dFdC, gemcitabine)-resistant human tumor cells. Methods and Materials: Human lung carcinoma cells SW-1573 (SWp) were made resistant to dFdC (SWg). Sensitivity to cisplatin (cDDP), paclitaxel,

  6. Stimulation of cytolytic T lymphocytes by azaguanine-resistant mouse tumor cells in selective hat medium

    International Nuclear Information System (INIS)

    Snick, J. van; Uyttenhove, C.; Pel, A. van; Boon, T.

    1981-01-01

    Primed syngeneic or umprimed allogeneic mouse spleen cells were stimulated with azaguanine-resistant P815 tumor cells that were killed by the addition of aminopterin to the stimulation medium. The recovery of lymphocytes and their cytolytic activity and specificity were similar to those obtained after stimulation with irradiated cells. This method conveniently replaces the inactivation of stimulatory cells by irradiation or mitomycin treatment. Moreover, it has the advantage of inactivating not only the stimulatory cells but also the tumor cells that often contaminate the spleens of tumor-bearing animals, provided these animals have been inoculated with azaguanine-resistant tumor cell mutants. (Auth.)

  7. Radiation induction of drug resistance in RIF-1: Correlation of tumor and cell culture results

    International Nuclear Information System (INIS)

    Moulder, J.E.; Hopwood, L.E.; Volk, D.M.; Davies, B.M.

    1991-01-01

    The RIF-1 tumor line contains cells that are resistant to various anti-neoplastic drugs, including 5-fluorouracil (5FU), methotrexate (MTX), adriamycin (ADR), and etoposide (VP16). The frequency of these drug-resistant cells is increased after irradiation. The frequency of drug-resistant cells and the magnitude of radiation-induced drug resistance are different in cell culture than in tumors. The dose-response and expression time relationships for radiation induction of drug resistance observed in RIF-1 tumors are unusual.We hypothesize that at high radiation doses in vivo, we are selecting for cells that are both drug resistant and radiation resistant due to microenvironmental factors, whereas at low radiation doses in vivo and all radiation doses in vitro, we are observing true mutants. These studies indicate that there can be significant differences in drug-resistance frequencies between tumors and their cell lines of origin, and that radiation induction of drug resistance depends significantly on whether the induction is done in tumors or in cell culture. These results imply that theories about the induction of drug resistance that are based on cell culture studies may be inapplicable to the induction of drug resistance in tumors

  8. Cell kinetics of Ehrlich ascites carcinoma transplanted in mice with different degrees of tumor resistance

    International Nuclear Information System (INIS)

    Brandt, K.L.B.

    1974-01-01

    Cell proliferation kinetics of Ehrlich ascites carcinoma grown in two strains of mice with different degrees of resistance to this tumor were examined. In the first portion of the study, growth of Ehrlich ascites carcinoma in nonresistant Swiss (Iowa) and slightly resistant CF1 mice was examined by measuring animal weight gain and host survival time after intraperitoneal injection of tumor cells. Since it appeared that CF1 mice were inherently more resistant than Swiss mice to the Ehrlich carcinoma, the second part of this investigation involved attempts to immunize CF1 mice against the tumor. Subcutaneous injections of Ehrlich cells previously exposed in vitro to 5000 R of 250 kVp x rays were utilized. One immunizing inoculation of lethally irradiated tumor cells afforded protection against an intraperitoneal challenge of 40 thousand Ehrlich cells. By varying the number and timing of immunizing inoculations it was possible to induce different degrees of tumor resistance in these mice. The most effective immunizing procedure utilized multiple inoculations of lethally irradiated tumor cells (LITC), followed by challenges with viable tumor cells (less than 1 million) which were rejected. These mice could then resist challenge inocula of 4 million viable tumor cells. In a few animals the immunizing procedures were ineffective; these animals, when challenged, developed even larger tumors than control mice. Tumor cell proliferation kinetics in these animals as well as in mice that were rejecting the tumor were examined in the third phase of the project. A shortening of the cell cycle was observed in almost all LITC-treated mice, whether tumor growth was eventually inhibited or stimulated. Decreased duration of the DNA-synthesis phase (S) of the tumor cell cycle was also a consistent finding. The role of the immune response in stimulating mitosis as well as in killing foreign cells was discussed. (U.S.)

  9. Colon cancer stem cells dictate tumor growth and resist cell death by production of interleukin-4.

    Science.gov (United States)

    Todaro, Matilde; Alea, Mileidys Perez; Di Stefano, Anna B; Cammareri, Patrizia; Vermeulen, Louis; Iovino, Flora; Tripodo, Claudio; Russo, Antonio; Gulotta, Gaspare; Medema, Jan Paul; Stassi, Giorgio

    2007-10-11

    A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor. Here, we describe the identification and characterization of such cells from colon carcinomas using the stem cell marker CD133 that accounts around 2% of the cells in human colon cancer. The CD133(+) cells grow in vitro as undifferentiated tumor spheroids, and they are both necessary and sufficient to initiate tumor growth in immunodeficient mice. Xenografts resemble the original human tumor maintaining the rare subpopulation of tumorigenic CD133(+) cells. Further analysis revealed that the CD133(+) cells produce and utilize IL-4 to protect themselves from apoptosis. Consistently, treatment with IL-4Ralpha antagonist or anti-IL-4 neutralizing antibody strongly enhances the antitumor efficacy of standard chemotherapeutic drugs through selective sensitization of CD133(+) cells. Our data suggest that colon tumor growth is dictated by stem-like cells that are treatment resistant due to the autocrine production of IL-4.

  10. pH regulation in sensitive and multidrug resistant Ehrlich ascites tumor cells

    DEFF Research Database (Denmark)

    Litman, Thomas; Pedersen, S F; Kramhøft, B

    1998-01-01

    Maintenance and regulation of intracellular pH (pHi) was studied in wild-type Ehrlich ascites tumor cells (EHR2) and five progressively daunorubicin-resistant, P-glycoprotein (P-gp)-expressing strains, the maximally resistant of which is EHR2/1.3. Steady-state pHi was similar in cells expressing...

  11. Combined cytotoxic effects of tumor necrosis factor-alpha with various cytotoxic agents in tumor cell lines that are drug resistant due to mutated p53

    NARCIS (Netherlands)

    Sleijfer, S; Le, T. K. P.; de Jong, S.; Timmer-Bosscha, H; Withoff, S; Mulder, NH

    Several studies suggest that tumor necrosis factor-alpha (TNF) is able to overcome drug resistance in tumors. Whether TNF is able to do so in tumor cell lines that are drug resistant due to a mutation in the tumor suppressor gene p53 is unclear. Therefore, we studied the in vitro cytotoxic effects

  12. Sensitivity to ionizing radiation and chemotherapeutic agents in gemcitabine-resistant human tumor cell lines

    International Nuclear Information System (INIS)

    Bree, Chris van; Kreder, Natasja Castro; Loves, Willem J.P.; Franken, Nicolaas A.P.; Peters, Godefridus J.; Haveman, Jaap

    2002-01-01

    Purpose: To determine cross-resistance to anti-tumor treatments in 2',2'difluorodeoxycytidine (dFdC, gemcitabine)-resistant human tumor cells. Methods and Materials: Human lung carcinoma cells SW-1573 (SWp) were made resistant to dFdC (SWg). Sensitivity to cisplatin (cDDP), paclitaxel, 5-fluorouracil (5-FU), methotrexate (MTX), cytarabine (ara-C), and dFdC was measured by a proliferation assay. Radiosensitivity and radioenhancement by dFdC of this cell panel and the human ovarian carcinoma cell line A2780 and its dFdC-resistant variant AG6000 were determined by clonogenic assay. Bivariate flowcytometry was performed to study cell cycle changes. Results: In the SWg, a complete deoxycytidine kinase (dCK) deficiency was found on mRNA and protein level. This was accompanied by a 10-fold decrease in dCK activity which resulted in the >1000-fold resistance to dFdC. Sensitivity to other anti-tumor drugs was not altered, except for ara-C (>100-fold resistance). Radiosensitivity was not altered in the dFdC-resistant cell lines SWg and AG6000. High concentrations (50-100 μM dFdC) induced radioenhancement in the dFdC-resistant cell lines similar to the radioenhancement obtained at lower concentrations (10 nM dFdC) in the parental lines. An early S-phase arrest was found in all cell lines after dFdC treatment where radioenhancement was achieved. Conclusions: In the dFdC-resistant lung tumor cell line SWg, the deficiency in dCK is related to the resistance to dFdC and ara-C. No cross-resistance was observed to other anti-tumor drugs used for the treatment in lung cancer. Sensitivity to ionizing radiation was not altered in two different dFdC-resistant cell lines. Resistance to dFdC does not eliminate the ability of dFdC to sensitize cells to radiation

  13. Downregulation of taurine uptake in multidrug resistant Ehrlich ascites tumor cells

    DEFF Research Database (Denmark)

    Poulsen, K A; Litman, Thomas; Eriksen, J

    2002-01-01

    In daunorubicin resistant Ehrlich ascites tumor cells (DNR), the initial taurine uptake was reduced by 56% as compared to the parental, drug sensitive Ehrlich cells. Kinetic experiments indicated that taurine uptake in Ehrlich cells occurs via both high- and low-affinity transporters. The maximal...... rate constant for the initial taurine uptake was reduced by 45% (high-affinity system) and 49% (low affinity system) in the resistant subline whereas the affinity of the transporters to taurine was unchanged. By immunoblotting we identified 3 TauT protein bands in the 50-70 kDa region. A visible...... reduction in the intensity of the band with the lowest molecular weight was observed in resistant cells. Quantitative RT-PCR indicated a significant reduction in the amount of taurine transporter mRNA in the resistant cells. Drug resistance in DNR Ehrlich cells is associated with overexpression of the mdr1...

  14. Genetic Determinants of Cisplatin Resistance in Patients With Advanced Germ Cell Tumors.

    Science.gov (United States)

    Bagrodia, Aditya; Lee, Byron H; Lee, William; Cha, Eugene K; Sfakianos, John P; Iyer, Gopa; Pietzak, Eugene J; Gao, Sizhi Paul; Zabor, Emily C; Ostrovnaya, Irina; Kaffenberger, Samuel D; Syed, Aijazuddin; Arcila, Maria E; Chaganti, Raju S; Kundra, Ritika; Eng, Jana; Hreiki, Joseph; Vacic, Vladimir; Arora, Kanika; Oschwald, Dayna M; Berger, Michael F; Bajorin, Dean F; Bains, Manjit S; Schultz, Nikolaus; Reuter, Victor E; Sheinfeld, Joel; Bosl, George J; Al-Ahmadie, Hikmat A; Solit, David B; Feldman, Darren R

    2016-11-20

    Purpose Owing to its exquisite chemotherapy sensitivity, most patients with metastatic germ cell tumors (GCTs) are cured with cisplatin-based chemotherapy. However, up to 30% of patients with advanced GCT exhibit cisplatin resistance, which requires intensive salvage treatment, and have a 50% risk of cancer-related death. To identify a genetic basis for cisplatin resistance, we performed whole-exome and targeted sequencing of cisplatin-sensitive and cisplatin-resistant GCTs. Methods Men with GCT who received a cisplatin-containing chemotherapy regimen and had available tumor tissue were eligible to participate in this study. Whole-exome sequencing or targeted exon-capture-based sequencing was performed on 180 tumors. Patients were categorized as cisplatin sensitive or cisplatin resistant by using a combination of postchemotherapy parameters, including serum tumor marker levels, radiology, and pathology at surgical resection of residual disease. Results TP53 alterations were present exclusively in cisplatin-resistant tumors and were particularly prevalent among primary mediastinal nonseminomas (72%). TP53 pathway alterations including MDM2 amplifications were more common among patients with adverse clinical features, categorized as poor risk according to the International Germ Cell Cancer Collaborative Group (IGCCCG) model. Despite this association, TP53 and MDM2 alterations predicted adverse prognosis independent of the IGCCCG model. Actionable alterations, including novel RAC1 mutations, were detected in 55% of cisplatin-resistant GCTs. Conclusion In GCT, TP53 and MDM2 alterations were associated with cisplatin resistance and inferior outcomes, independent of the IGCCCG model. The finding of frequent TP53 alterations among mediastinal primary nonseminomas may explain the more frequent chemoresistance observed with this tumor subtype. A substantial portion of cisplatin-resistant GCTs harbor actionable alterations, which might respond to targeted therapies. Genomic

  15. Cytotoxicity of the indole alkaloid reserpine from Rauwolfia serpentina against drug-resistant tumor cells.

    Science.gov (United States)

    Abdelfatah, Sara A A; Efferth, Thomas

    2015-02-15

    The antihypertensive reserpine is an indole alkaloid from Rauwolfia serpentina and exerts also profound activity against cancer cells in vitro and in vivo. The present investigation was undertaken to investigate possible modes of action to explain its activity toward drug-resistant tumor cells. Sensitive and drug-resistant tumor cell lines overexpressing P-glycoprotein (ABCB1/MDR1), breast cancer resistance protein (ABCG2/BCRP), mutation-activated epidermal growth factor receptor (EGFR), wild-type and p53-knockout cells as well as the NCI panel of cell lines from different tumor origin were analyzed. Reserpine's cytotoxicity was investigated by resazurin and sulforhodamine assays, flow cytometry, and COMPARE and hierarchical cluster analyses of transcriptome-wide microarray-based RNA expressions. P-glycoprotein- or BCRP overexpressing tumor cells did not reveal cross-resistance to reserpine. EGFR-overexpressing cells were collateral sensitive and p53- Knockout cells cross-resistant to this drug compared to their wild-type parental cell lines. Reserpine increased the uptake of doxorubicin in P-glycoprotein-overexpressing cells, indicating that reserpine inhibited the efflux function of P-glycoprotein. Using molecular docking, we found that reserpine bound with even higher binding energy to P-glycoprotein and EGFR than the control drugs verapamil (P-glycoprotein inhibitor) and erlotinib (EGFR inhibitor). COMPARE and cluster analyses of microarray data showed that the mRNA expression of a panel of genes predicted the sensitivity or resistance of the NCI tumor cell line panel with statistical significance. The genes belonged to diverse pathways and biological functions, e.g. cell survival and apoptosis, EGFR activation, regulation of angiogenesis, cell mobility, cell adhesion, immunological functions, mTOR signaling, and Wnt signaling. The lack of cross-resistance to most resistance mechanisms and the collateral sensitivity in EGFR-transfectants compared to wild

  16. Relationship between laminin binding capacity and laminin expression on tumor cells sensitive or resistant to natural cell-mediated cytotoxicity

    International Nuclear Information System (INIS)

    Laybourn, K.A.; Varani, J.; Fligiel, S.E.G.; Hiserodt, J.C.

    1986-01-01

    Previous studies have identified the presence of laminin binding sites on murine NK and NC sensitive tumor cells by 125 I-laminin binding and laminin induced cell-cell aggregation. The finding that the addition of exogenous laminin inhibits NK/NC binding to sensitive tumor cells suggests laminin binding sites may serve as target antigens for NK cells. The present study extends earlier reports by analyzing a large panel of tumor cells for laminin binding capacity, laminin expression and sensitivity to NK/NC killing. The data indicate that all tumor cells which bind to NK/NC cells (8 lines tested) express laminin binding sites. All of these tumor cells were capable of competing for NK lysis of YAC-1 cells in cold target competition assays, and all bound enriched NK cells in direct single cell binding assays. In contrast, tumor cells expressing high levels of surface laminin (B16 melanomas, C57B1/6 fibrosarcomas, and RAS transfected 3T3 fibroblasts) but low levels of laminin binding capacity did not bind NK/NC cells and were resistant to lysis. These data support the hypothesis that expression of laminin/laminin binding sites may contribute to tumor cell sensitivity to NK/NC binding and/or killing

  17. Colon cancer stem cells dictate tumor growth and resist cell death by production of interleukin-4

    NARCIS (Netherlands)

    Todaro, Matilde; Alea, Mileidys Perez; Di Stefano, Anna B.; Cammareri, Patrizia; Vermeulen, Louis; Iovino, Flora; Tripodo, Claudio; Russo, Antonio; Gulotta, Gaspare; Medema, Jan Paul; Stassi, Giorgio

    2007-01-01

    A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor. Here, we describe the identification and characterization of such cells from colon carcinomas using the stem cell marker CD133 that accounts around 2% of the cells in human colon cancer. The

  18. Alterations in tumor necrosis factor signaling pathways are associated with cytotoxicity and resistance to taxanes: a study in isogenic resistant tumor cells

    Science.gov (United States)

    2012-01-01

    Introduction The taxanes paclitaxel and docetaxel are widely used in the treatment of breast, ovarian, and other cancers. Although their cytotoxicity has been attributed to cell-cycle arrest through stabilization of microtubules, the mechanisms by which tumor cells die remains unclear. Paclitaxel has been shown to induce soluble tumor necrosis factor alpha (sTNF-α) production in macrophages, but the involvement of TNF production in taxane cytotoxicity or resistance in tumor cells has not been established. Our study aimed to correlate alterations in the TNF pathway with taxane cytotoxicity and the acquisition of taxane resistance. Methods MCF-7 cells or isogenic drug-resistant variants (developed by selection for surviving cells in increasing concentrations of paclitaxel or docetaxel) were assessed for sTNF-α production in the absence or presence of taxanes by enzyme-linked immunosorbent assay (ELISA) and for sensitivity to docetaxel or sTNF-α by using a clonogenic assay (in the absence or presence of TNFR1 or TNFR2 neutralizing antibodies). Nuclear factor (NF)-κB activity was also measured with ELISA, whereas gene-expression changes associated with docetaxel resistance in MCF-7 and A2780 cells were determined with microarray analysis and quantitative reverse transcription polymerase chain reaction (RTqPCR). Results MCF-7 and A2780 cells increased production of sTNF-α in the presence of taxanes, whereas docetaxel-resistant variants of MCF-7 produced high levels of sTNF-α, although only within a particular drug-concentration threshold (between 3 and 45 nM). Increased production of sTNF-α was NF-κB dependent and correlated with decreased sensitivity to sTNF-α, decreased levels of TNFR1, and increased survival through TNFR2 and NF-κB activation. The NF-κB inhibitor SN-50 reestablished sensitivity to docetaxel in docetaxel-resistant MCF-7 cells. Gene-expression analysis of wild-type and docetaxel-resistant MCF-7, MDA-MB-231, and A2780 cells identified changes

  19. Celecoxib decreases growth and angiogenesis and promotes apoptosis in a tumor cell line resistant to chemotherapy

    Directory of Open Access Journals (Sweden)

    Carlos Rosas

    2014-01-01

    Full Text Available BACKGROUND: During the last few years it has been shown in several laboratories that Celecoxib (Cx, a non-steroidal anti-inflammatory agent (NSAID normally used for pain and arthritis, mediates antitumor and antiangiogenic effects. However, the effects of this drug on a tumor cell line resistant to chemotherapeutical drugs used in cancer have not been described. Herein we evaluate the angiogenic and antitumor effects of Cx in the development of a drug-resistant mammary adenocarcinoma tumor (TA3-MTXR. RESULTS: Cx reduces angiogenesis in the chick embryonic chorioallantoic membrane assay (CAM, inhibits the growth and microvascular density of the murine TA3-MTXR tumor, reduces microvascular density of tumor metastases, promotes apoptosis and reduces vascular endothelial growth factor (VEGF production and cell proliferation in the tumor. CONCLUSION: The antiangiogenic and antitumor Cx effects correlate with its activity on other tumor cell lines, suggesting that Prostaglandins (PGs and VEGF production are involved. These results open the possibility of using Celecoxib combined with other experimental therapies, ideally aiming to get synergic effects.

  20. The necrotic signal induced by mycophenolic acid overcomes apoptosis-resistance in tumor cells.

    Directory of Open Access Journals (Sweden)

    Gwendaline Guidicelli

    Full Text Available BACKGROUND: The amount of inosine monophosphate dehydrogenase (IMPDH, a pivotal enzyme for the biosynthesis of the guanosine tri-phosphate (GTP, is frequently increased in tumor cells. The anti-viral agent ribavirin and the immunosuppressant mycophenolic acid (MPA are potent inhibitors of IMPDH. We recently showed that IMPDH inhibition led to a necrotic signal requiring the activation of Cdc42. METHODOLOGY/PRINCIPAL FINDINGS: Herein, we strengthened the essential role played by this small GTPase in the necrotic signal by silencing Cdc42 and by the ectopic expression of a constitutive active mutant of Cdc42. Since resistance to apoptosis is an essential step for the tumorigenesis process, we next examined the effect of the MPA-mediated necrotic signal on different tumor cells demonstrating various mechanisms of resistance to apoptosis (Bcl2-, HSP70-, Lyn-, BCR-ABL-overexpressing cells. All tested cells remained sensitive to MPA-mediated necrotic signal. Furthermore, inhibition of IMPDH activity in Chronic Lymphocytic Leukemia cells was significantly more efficient at eliminating malignant cells than apoptotic inducers. CONCLUSIONS/SIGNIFICANCE: These findings indicate that necrosis and apoptosis are split signals that share few if any common hub of signaling. In addition, the necrotic signaling pathway induced by depletion of the cellular amount of GTP/GDP would be of great interest to eliminate apoptotic-resistant tumor cells.

  1. Apoptosis resistance in epithelial tumors is mediated by tumor-cell-derived interleukin-4.

    Science.gov (United States)

    Todaro, M; Lombardo, Y; Francipane, M G; Alea, M Perez; Cammareri, P; Iovino, F; Di Stefano, A B; Di Bernardo, C; Agrusa, A; Condorelli, G; Walczak, H; Stassi, G

    2008-04-01

    We investigated the mechanisms involved in the resistance to cell death observed in epithelial cancers. Here, we identify that primary epithelial cancer cells from colon, breast and lung carcinomas express high levels of the antiapoptotic proteins PED, cFLIP, Bcl-xL and Bcl-2. These cancer cells produced interleukin-4 (IL-4), which amplified the expression levels of these antiapoptotic proteins and prevented cell death induced upon exposure to TRAIL or other drug agents. IL-4 blockade resulted in a significant decrease in the growth rate of epithelial cancer cells and sensitized them, both in vitro and in vivo, to apoptosis induction by TRAIL and chemotherapy via downregulation of the antiapoptotic factors PED, cFLIP, Bcl-xL and Bcl-2. Furthermore, we provide evidence that exogenous IL-4 was able to upregulate the expression levels of these antiapoptotic proteins and potently stabilized the growth of normal epithelial cells rendering them apoptosis resistant. In conclusion, IL-4 acts as an autocrine survival factor in epithelial cells. Our results indicate that inhibition of IL-4/IL-4R signaling may serve as a novel treatment for epithelial cancers.

  2. Expression of EGFR Under Tumor Hypoxia: Identification of a Subpopulation of Tumor Cells Responsible for Aggressiveness and Treatment Resistance

    Energy Technology Data Exchange (ETDEWEB)

    Hoogsteen, Ilse J., E-mail: i.hoogsteen@rther.umcn.nl [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Marres, Henri A.M.; Hoogen, Franciscus J.A. van den [Department of Otorhinolaryngology/Head-Neck Surgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Rijken, Paul F.J.W.; Lok, Jasper; Bussink, Johan; Kaanders, Johannes H.A.M. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)

    2012-11-01

    Purpose: Overexpression of epidermal growth factor receptor (EGFR) and tumor hypoxia have been shown to correlate with worse outcome in several types of cancer including head-and-neck squamous cell carcinoma. Little is known about the combination and possible interactions between the two phenomena. Methods and Materials: In this study, 45 cases of histologically confirmed squamous cell carcinomas of the head and neck were analyzed. All patients received intravenous infusions of the exogenous hypoxia marker pimonidazole prior to biopsy. Presence of EGFR, pimonidazole binding, and colocalization between EGFR and tumor hypoxia were examined using immunohistochemistry. Results: Of all biopsies examined, respectively, 91% and 60% demonstrated EGFR- and pimonidazole-positive areas. A weak but significant association was found between the hypoxic fractions of pimonidazole (HFpimo) and EGFR fractions (F-EGFR) and between F-EGFR and relative vascular area. Various degrees of colocalization between hypoxia and EGFR were found, increasing with distance from the vasculature. A high fraction of EGFR was correlated with better disease-free and metastasis-free survival, whereas a high degree of colocalization correlated with poor outcome. Conclusions: Colocalization of hypoxia and EGFR was demonstrated in head-and-neck squamous cell carcinomas, predominantly at longer distances from vessels. A large amount of colocalization was associated with poor outcome, which points to a survival advantage of hypoxic cells that are also able to express EGFR. This subpopulation of tumor cells might be indicative of tumor aggressiveness and be partly responsible for treatment resistance.

  3. Treatment of a solid tumor using engineered drug-resistant immunocompetent cells and cytotoxic chemotherapy.

    Science.gov (United States)

    Dasgupta, Anindya; Shields, Jordan E; Spencer, H Trent

    2012-07-01

    Multimodal therapy approaches, such as combining chemotherapy agents with cellular immunotherapy, suffers from potential drug-mediated toxicity to immune effector cells. Overcoming such toxic effects of anticancer cellular products is a potential critical barrier to the development of combined therapeutic approaches. We are evaluating an anticancer strategy that focuses on overcoming such a barrier by genetically engineering drug-resistant variants of immunocompetent cells, thereby allowing for the coadministration of cellular therapy with cytotoxic chemotherapy, a method we refer to as drug-resistant immunotherapy (DRI). The strategy relies on the use of cDNA sequences that confer drug resistance and recombinant lentiviral vectors to transfer nucleic acid sequences into immunocompetent cells. In the present study, we evaluated a DRI-based strategy that incorporates the immunocompetent cell line NK-92, which has intrinsic antitumor properties, genetically engineered to be resistant to both temozolomide and trimetrexate. These immune effector cells efficiently lysed neuroblastoma cell lines, which we show are also sensitive to both chemotherapy agents. The antitumor efficacy of the DRI strategy was demonstrated in vivo, whereby neuroblastoma-bearing NOD/SCID/γ-chain knockout (NSG) mice treated with dual drug-resistant NK-92 cell therapy followed by dual cytotoxic chemotherapy showed tumor regression and significantly enhanced survival compared with animals receiving either nonengineered cell-based therapy and chemotherapy, immunotherapy alone, or chemotherapy alone. These data show there is a benefit to using drug-resistant cellular therapy when combined with cytotoxic chemotherapy approaches.

  4. Verapamil inhibits tumor progression of chemotherapy-resistant pancreatic cancer side population cells

    Science.gov (United States)

    ZHAO, LU; ZHAO, YUE; SCHWARZ, BETTINA; MYSLIWIETZ, JOSEF; HARTIG, ROLAND; CAMAJ, PETER; BAO, QI; JAUCH, KARL-WALTER; GUBA, MAKUS; ELLWART, JOACHIM WALTER; NELSON, PETER JON; BRUNS, CHRISTIANE JOSEPHINE

    2016-01-01

    Tumor side population (SP) cells display stem-like properties that can be modulated by treatment with the calcium channel blocker verapamil. Verapamil can enhance the cytotoxic effects of chemotherapeutic drugs and multi-drug resistance by targeting the transport function of the P-glycoprotein (P-gp). This study focused on the therapeutic potential of verapamil on stem-like SP tumor cells, and further investigated its chemosensitizing effects using L3.6pl and AsPC-1 pancreatic carcinoma models. As compared to parental L3.6pl cells (0.9±0.22%), L3.6pl gemcitabine-resistant cells (L3.6plGres) showed a significantly higher percentage of SP cells (5.38±0.99%) as detected by Hoechst 33342/FACS assays. The L3.6plGres SP cells showed stable gemcitabine resistance, enhanced colony formation ability and increased tumorigenicity. Verapamil effectively inhibited L3.6plGres and AsPC-1 SP cell proliferation in vitro. A pro-apoptotic effect of verapamil was observed in L3.6pl cells, but not in L3.6plGres cells, which was linked to their differential expression of P-gp and equilibrative nucleoside transporter-1 (ENT-1). In an orthotopic pancreatic cancer mouse model, both low and high dose verapamil was shown to substantially reduce L3.6plGres-SP cell tumor growth and metastasis, enhance tumor apoptosis, and reduce microvascular density. PMID:27177126

  5. Down-regulation of HSP27 sensitizes TRAIL-resistant tumor cell to TRAIL-induced apoptosis

    DEFF Research Database (Denmark)

    Zhuang, Hongqin; Jiang, Weiwei; Cheng, Wei

    2010-01-01

    Tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL) has recently emerged as a cancer therapeutic agent because it preferentially induces apoptosis in human cancer over normal cells. Most tumor cells, including lung cancer cell line A549, unfortunately, are resistant to TRAIL tre...

  6. Factors determining sensitivity or resistance of tumor cell lines towards artesunate.

    Science.gov (United States)

    Sertel, Serkan; Eichhorn, Tolga; Sieber, Sebastian; Sauer, Alexandra; Weiss, Johanna; Plinkert, Peter K; Efferth, Thomas

    2010-04-15

    Clinical oncology is still challenged by the development of drug resistance of tumors that result in poor prognosis for patients. There is an urgent necessity to understand the molecular mechanisms of resistance and to develop novel therapy strategies. Artesunate (ART) is an anti-malarial drug, which also exerts profound cytotoxic activity towards cancer cells. We first applied a gene-hunting approach using cluster and COMPARE analyses of microarray-based transcriptome-wide mRNA expression profiles. Among the genes identified by this approach were genes from diverse functional groups such as structural constituents of ribosomes (RPL6, RPL7, RPS12, RPS15A), kinases (CABC1, CCT2, RPL41), transcriptional and translational regulators (SFRS2, TUFM, ZBTB4), signal transducers (FLNA), control of cell growth and proliferation (RPS6), angiogenesis promoting factors (ITGB1), and others (SLC25A19, NCKAP1, BST1, DBH, FZD7, NACA, MTHFD2). Furthermore, we applied a candidate gene approach and tested the role of resistance mechanisms towards established anti-cancer drugs for ART resistance. By using transfected or knockout cell models we found that the tumor suppressor p16(INK4A) and the anti-oxidant protein, catalase, conferred resistance towards ART, while the oncogene HPV-E6 conferred sensitivity towards ART. The tumor suppressor p53 and its downstream protein, p21, as well as the anti-oxidant manganese-dependent superoxide dismutase did not affect cellular response to ART. In conclusion, our pharmacogenomic approach revealed that response of tumor cells towards ART is multi-factorial and is determined by gene expression associated with either ART sensitivity or resistance. At least some of the functional groups of genes (e.g. angiogenesis promoting factors, cell growth and proliferation-associated genes signal transducers and kinases) are also implicated in clinical responsiveness of tumors towards chemotherapy. It merits further investigation, whether ART is responsive in

  7. Tumor Heterogeneity and Drug Resistance

    International Nuclear Information System (INIS)

    Kucerova, L.; Skolekova, S.; Kozovska, Z.

    2015-01-01

    New generation of sequencing methodologies revealed unexpected complexity and genomic alterations linked with the tumor subtypes. This diversity exists across the tumor types, histologic tumor subtypes and subsets of the tumor cells within the same tumor. This phenomenon is termed tumor heterogeneity. Regardless of its origin and mechanisms of development it has a major impact in the clinical setting. Genetic, phenotypic and expression pattern diversity of tumors plays critical role in the selection of suitable treatment and also in the prognosis prediction. Intratumoral heterogeneity plays a key role in the intrinsic and acquired chemoresistance to cytotoxic and targeted therapies. In this review we focus on the mechanisms of intratumoral and inter tumoral heterogeneity and their relationship to the drug resistance. Understanding of the mechanisms and spatiotemporal dynamics of tumor heterogeneity development before and during the therapy is important for the ability to design individual treatment protocols suitable in the given molecular context. (author)

  8. Alternating current electrical stimulation enhanced chemotherapy: a novel strategy to bypass multidrug resistance in tumor cells

    International Nuclear Information System (INIS)

    Janigro, Damir; Perju, Catalin; Fazio, Vincent; Hallene, Kerri; Dini, Gabriele; Agarwal, Mukesh K; Cucullo, Luca

    2006-01-01

    Tumor burden can be pharmacologically controlled by inhibiting cell division and by direct, specific toxicity to the cancerous tissue. Unfortunately, tumors often develop intrinsic pharmacoresistance mediated by specialized drug extrusion mechanisms such as P-glycoprotein. As a consequence, malignant cells may become insensitive to various anti-cancer drugs. Recent studies have shown that low intensity very low frequency electrical stimulation by alternating current (AC) reduces the proliferation of different tumor cell lines by a mechanism affecting potassium channels while at intermediate frequencies interfere with cytoskeletal mechanisms of cell division. The aim of the present study is to test the hypothesis that permeability of several MDR1 over-expressing tumor cell lines to the chemotherapic agent doxorubicin is enhanced by low frequency, low intensity AC stimulation. We grew human and rodent cells (C6, HT-1080, H-1299, SKOV-3 and PC-3) which over-expressed MDR1 in 24-well Petri dishes equipped with an array of stainless steel electrodes connected to a computer via a programmable I/O board. We used a dedicated program to generate and monitor the electrical stimulation protocol. Parallel cultures were exposed for 3 hours to increasing concentrations (1, 2, 4, and 8 μM) of doxorubicin following stimulation to 50 Hz AC (7.5 μA) or MDR1 inhibitor XR9576. Cell viability was assessed by determination of adenylate kinase (AK) release. The relationship between MDR1 expression and the intracellular accumulation of doxorubicin as well as the cellular distribution of MDR1 was investigated by computerized image analysis immunohistochemistry and Western blot techniques. By the use of a variety of tumor cell lines, we show that low frequency, low intensity AC stimulation enhances chemotherapeutic efficacy. This effect was due to an altered expression of intrinsic cellular drug resistance mechanisms. Immunohistochemical, Western blot and fluorescence analysis revealed

  9. Characterization and drug resistance patterns of Ewing's sarcoma family tumor cell lines.

    Directory of Open Access Journals (Sweden)

    William A May

    Full Text Available Despite intensive treatment with chemotherapy, radiotherapy and surgery, over 70% of patients with metastatic Ewing's Sarcoma Family of Tumors (EFT will die of their disease. We hypothesize that properly characterized laboratory models reflecting the drug resistance of clinical tumors will facilitate the application of new therapeutic agents to EFT. To determine resistance patterns, we studied newly established EFT cell lines derived from different points in therapy: two established at diagnosis (CHLA-9, CHLA-32, two after chemotherapy and progressive disease (CHLA-10, CHLA-25, and two at relapse after myeloablative therapy and autologous bone marrow transplantation (post-ABMT (CHLA-258, COG-E-352. The new lines were compared to widely studied EFT lines TC-71, TC-32, SK-N-MC, and A-673. These lines were extensively characterized with regard to identity (short tandem repeat (STR analysis, p53, p16/14 status, and EWS/ETS breakpoint and target gene expression profile. The DIMSCAN cytotoxicity assay was used to assess in vitro drug sensitivity to standard chemotherapy agents. No association was found between drug resistance and the expression of EWS/ETS regulated genes in the EFT cell lines. No consistent association was observed between drug sensitivity and p53 functionality or between drug sensitivity and p16/14 functionality across the cell lines. Exposure to chemotherapy prior to cell line initiation correlated with drug resistance of EFT cell lines in 5/8 tested agents at clinically achievable concentrations (CAC or the lower tested concentration (LTC: (cyclophosphamide (as 4-HC and doxorubicin at CAC, etoposide, irinotecan (as SN-38 and melphalan at LTC; P<0.1 for one agent, and P<0.05 for four agents. This panel of well-characterized drug-sensitive and drug-resistant cell lines will facilitate in vitro preclinical testing of new agents for EFT.

  10. Human CAR T cells with cell-intrinsic PD-1 checkpoint blockade resist tumor-mediated inhibition

    Science.gov (United States)

    Cherkassky, Leonid; Morello, Aurore; Villena-Vargas, Jonathan; Feng, Yang; Dimitrov, Dimiter S.; Jones, David R.; Sadelain, Michel; Adusumilli, Prasad S.

    2016-01-01

    Following immune attack, solid tumors upregulate coinhibitory ligands that bind to inhibitory receptors on T cells. This adaptive resistance compromises the efficacy of chimeric antigen receptor (CAR) T cell therapies, which redirect T cells to solid tumors. Here, we investigated whether programmed death-1–mediated (PD-1–mediated) T cell exhaustion affects mesothelin-targeted CAR T cells and explored cell-intrinsic strategies to overcome inhibition of CAR T cells. Using an orthotopic mouse model of pleural mesothelioma, we determined that relatively high doses of both CD28- and 4-1BB–based second-generation CAR T cells achieved tumor eradication. CAR-mediated CD28 and 4-1BB costimulation resulted in similar levels of T cell persistence in animals treated with low T cell doses; however, PD-1 upregulation within the tumor microenvironment inhibited T cell function. At lower doses, 4-1BB CAR T cells retained their cytotoxic and cytokine secretion functions longer than CD28 CAR T cells. The prolonged function of 4-1BB CAR T cells correlated with improved survival. PD-1/PD-1 ligand [PD-L1] pathway interference, through PD-1 antibody checkpoint blockade, cell-intrinsic PD-1 shRNA blockade, or a PD-1 dominant negative receptor, restored the effector function of CD28 CAR T cells. These findings provide mechanistic insights into human CAR T cell exhaustion in solid tumors and suggest that PD-1/PD-L1 blockade may be an effective strategy for improving the potency of CAR T cell therapies. PMID:27454297

  11. Tumor necrosis factor: specific binding and internalization in sensitive and resistant cells

    International Nuclear Information System (INIS)

    Tsujimoto, M.; Yip, Y.K.; Vilcek, J.

    1985-01-01

    Highly purified, Escherichia coli-derived recombinant human tumor necrosis factor (TNF) was labeled with 125 I and employed to determine receptor binding, internalization, and intracellular degradation in murine L929 cells (highly sensitive to the cytotoxic action of TNF) and in diploid human FS-4 cells (resistant to TNF cytotoxicity). 125 I-labeled TNF bound specifically to high-affinity receptors on both L929 and FS-4 cells. Scatchard analysis of the binding data indicated the presence of 2200 binding sites per L929 cell and 7500 binding sites per FS-4 cell. The calculated dissociation constants are 6.1 x 10 -10 M and 3.2 x 10 -10 M for L929 and FS-4 cells, respectively. In both L929 and FS-4 cells, incubation at 37 0 C resulted in a rapid internalization of the bulk of the cell-bound TNF, followed by the appearance of trichloroacetic acid-soluble 125 I radioactivity in the tissue culture medium, due to degradation of TNF. Degradation but not cellular uptake of TNF was inhibited in the presence of chloroquine (an inhibitor of lysosomal proteases) in both L929 and FS-4 cells, suggesting that degradation occurs intracellularly, probably within lysosomes. These results show that resistance of FS-4 cells to TNF cytotoxicity is not due to a lack of receptors or their inability to internalize and degrade TNF

  12. Structure-activity relationships of diverse xanthones against multidrug resistant human tumor cells.

    Science.gov (United States)

    Wang, Qiwen; Ma, Chenyao; Ma, Yun; Li, Xiang; Chen, Yong; Chen, Jianwei

    2017-02-01

    Thirteen xanthones were isolated naturally from the stem of Securidaca inappendiculata Hassk, and structure-activity relationships (SARs) of these compounds were comparatively predicted for their cytotoxic activity against three human multidrug resistant (MDR) cell lines MCF-7/ADR, SMMC-7721/Taxol, and A549/Taxol cells. The results showed that the selected xanthones exhibited different potent cytotoxic activity against the growth of different human tumor cell lines, and most of the xanthones exhibited selective cytotoxicity against SMMC-7721/Taxol cells. Furthermore, some tested xanthones showed stronger cytotoxicity than Cisplatin, which has been used in clinical application extensively. The SARs analysis revealed that the cytotoxic activities of diverse xanthones were affected mostly by the number and position of methoxyl and hydroxyl groups. Xanthones with more free hydroxyl and methoxyl groups increased the cytotoxic activity significantly, especially for those with the presence of C-3 hydroxyl and C-4 methoxyl groups. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. DNA from radiation resistant human tumor cells transfers resistance to NIH/3T3 cells with varying degrees of penetrance

    International Nuclear Information System (INIS)

    Kasid, U.; Dritschilo, A.; Weichselbaum, R.

    1987-01-01

    Experimental evidence suggests that clinical radiation resistance may correlate with in vitro radiation survival parameters. Specifically, they isolated several cell lines from radioresistant head and neck carcinomas with D/sub 0/ values greater than 2 Gy. The authors co-transfected DNA from cell line SQ2OB (D/sub 0/ = 2.4 Gy) with the rhoSVNeO plasmid into NIH/3T3 cells (D/sub 0/ = 1.7 Gy). Antibiotic G418 resistant, transformed clones were isolated and confirmed by Southern blotting to contain human alu, as well as rhoSVNeO sequences. Screening for radiation resistance with 8Gy (Cs-137) revealed that 3 of 4 tested hybrid clones show a radiation survival intermediate between NIH/3T3 and SQ2OB. This suggests that radiation resistance is a dominant, transfectable phenotype of mammalian cells and can be expressed in more sensitive cells. Karyotyping of resistant hybrid clones shows the presence of double minute chromosomes. Secondary transfection results and experiments to clone the genetic factors responsible for radiation resistance are in progress and results will be reported

  14. Dual responsive promoters to target therapeutic gene expression to radiation-resistant hypoxic tumor cells

    International Nuclear Information System (INIS)

    Chadderton, Naomi; Cowen, Rachel L.; Sheppard, Freda C.D.; Robinson, Suzanne; Greco, Olga; Scott, Simon D.; Stratford, Ian J.; Patterson, Adam V.; Williams, Kaye J.

    2005-01-01

    Purpose: Tumor hypoxia is unequivocally linked to poor radiotherapy outcome. This study aimed to identify enhancer sequences that respond maximally to a combination of radiation and hypoxia for use in genetic radiotherapy approaches. Methods and materials: The influence of radiation (5 Gy) and hypoxia (1% O 2 ) on reporter-gene expression driven by hypoxia (HRE) and radiation (Egr-1) responsive elements was evaluated in tumor cells grown as monolayers or multicellular spheroids. Hypoxia-inducible factor-1α (HIF-1α) and HIF-2α protein expression was monitored in parallel. Results: Of the sequences tested, an HRE from the phosphoglycerate kinase-1 gene (PGK-18[5+]) was maximally induced in response to hypoxia plus radiation in all 5 cell lines tested. The additional radiation treatment afforded a significant increase in the induction of PGK-18[5+] compared with hypoxia alone in 3 cell lines. HIF-1α/2α were induced by radiation but combined hypoxia/radiation treatment did not yield a further increase. The dual responsive nature of HREs was maintained when spheroids were irradiated after delivery of HRE constructs in a replication-deficient adenovirus. Conclusions: Hypoxia-responsive enhancer element sequences are dually responsive to combined radiation and hypoxic treatment. Their use in genetic radiotherapy in vivo could maximize expression in the most radio-resistant population at the time of radiation and also exploit microenvironmental changes after radiotherapy to yield additional switch-on

  15. Pancreatic islet cell tumor

    Science.gov (United States)

    ... cell tumors; Islet of Langerhans tumor; Neuroendocrine tumors; Peptic ulcer - islet cell tumor; Hypoglycemia - islet cell tumor ... stomach acid. Symptoms may include: Abdominal pain Diarrhea ... and small bowel Vomiting blood (occasionally) Glucagonomas make ...

  16. Hepatic natural killer cells exclusively kill splenic/blood natural killer-resistant tumor cells by the perforin/granzyme pathway

    NARCIS (Netherlands)

    Vermijlen, David; Luo, Dianzhong; Froelich, Christopher J.; Medema, Jan Paul; Kummer, Jean Alain; Willems, Erik; Braet, Filip; Wisse, Eddie

    2002-01-01

    Hepatic natural killer (NK) cells are located in the liver sinusoids adherent to the endothelium. Human and rat hepatic NK cells induce cytolysis in tumor cells that are resistant to splenic or blood NK cells. To investigate the mechanism of cell death, we examined the capacity of isolated, pure

  17. Estrogen receptor positive breast tumors resist chemotherapy by the overexpression of P53 in Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Fatma Ashour

    2018-06-01

    Full Text Available Background and Objectives: Breast cancer (BC is classified according to estrogen receptor (ER status into ER+ and ER− tumors. ER+ tumors have a worse response to chemotherapy compared to ER− tumors. BCL-2, TP53, BAX and NF-ΚB are involved in drug resistance in the ER+ tumors. Recently it was shown that Cancer Stem Cells (CSCs play an important role in drug resistance. In this study we tested the hypothesis that CSCs of the ER+ tumors resist drug through the overexpression of BCL-2, TP53, BAX and NF-ΚB. Methods: CSCs were isolated by anoikis resistance assay from MCF7 (ER+ and MDA-MB-231 (ER− cell lines. Isolated CSCs were treated with doxorubicin (DOX and the mRNA expression levels of BCL-2, TP53, BAX and NFKB were investigated by quantitative real time PCR (qPCR with and without treatment. Results: BCL-2, BAX and NF-ΚB showed decreased expression in MCF7 bulk cancer cells after DOX treatment whereas only BCL-2 and BAX showed decreased expression in MDA-MB-231 bulk cancer cells. Interestingly TP53 was the only gene showed a considerable increase in its expression in CSCs of the ER+ MCF7 cell line compared to bulk cancer cells. Moreover, TP53 was the only gene showing exceptionally higher level of expression in MCF7-CSCs compared to MDA-MB-231-CSCs. Conclusion: Our results suggest that CSCs in the ER+ cells escape the effect of DOX treatment by the elevation of p53 expression. Keywords: Breast cancer, Cancer Stem Cells, Drug resistance, Estrogen receptors

  18. Platelet-camouflaged nanococktail: Simultaneous inhibition of drug-resistant tumor growth and metastasis via a cancer cells and tumor vasculature dual-targeting strategy.

    Science.gov (United States)

    Jing, Lijia; Qu, Haijing; Wu, Dongqi; Zhu, Chaojian; Yang, Yongbo; Jin, Xing; Zheng, Jian; Shi, Xiangsheng; Yan, Xiufeng; Wang, Yang

    2018-01-01

    Multidrug resistance (MDR) poses a great challenge to cancer therapy. It is difficult to inhibit the growth of MDR cancer due to its chemoresistance. Furthermore, MDR cancers are more likely to metastasize, causing a high mortality among cancer patients. In this study, a nanomedicine RGD-NPVs@MNPs/DOX was developed by encapsulating melanin nanoparticles (MNPs) and doxorubicin (DOX) inside RGD peptide (c(RGDyC))-modified nanoscale platelet vesicles (RGD-NPVs) to efficiently inhibit the growth and metastasis of drug-resistant tumors via a cancer cells and tumor vasculature dual-targeting strategy. Methods: The in vitro immune evasion potential and the targeting performance of RGD-NPVs@MNPs/DOX were examined using RAW264.7, HUVECs, MDA-MB-231 and MDA-MB-231/ADR cells lines. We also evaluated the pharmacokinetic behavior and the in vivo therapeutic performance of RGD-NPVs@MNPs/DOX using a MDA-MB-231/ADR tumor-bearing nude mouse model. Results: By taking advantage of the self-recognizing property of the platelet membrane and the conjugated RGD peptides, RGD-NPVs@MNPs/DOX was found to evade immune clearance and target the αvβ3 integrin on tumor vasculature and resistant breast tumor cells. Under irradiation with a NIR laser, RGD-NPVs@MNPs/DOX produced a multipronged effect, including reversal of cancer MDR, efficient killing of resistant cells by chemo-photothermal therapy, elimination of tumor vasculature for blocking metastasis, and long-lasting inhibition of the expressions of VEGF, MMP2 and MMP9 within the tumor. Conclusion: This versatile nanomedicine of RGD-NPVs@MNPs/DOX integrating unique biomimetic properties, excellent targeting performance, and comprehensive therapeutic strategies in one formulation might bring opportunities to MDR cancer therapy.

  19. Cell-cycle-dependent drug-resistant quiescent cancer cells induce tumor angiogenesis after chemotherapy as visualized by real-time FUCCI imaging

    Science.gov (United States)

    Yano, Shuya; Takehara, Kiyoto; Tazawa, Hiroshi; Kishimoto, Hiroyuki; Urata, Yasuo; Kagawa, Shunsuke; Fujiwara, Toshiyoshi; Hoffman, Robert M.

    2017-01-01

    ABSTRACT We previously demonstrated that quiescent cancer cells in a tumor are resistant to conventional chemotherapy as visualized with a fluorescence ubiquitination cell cycle indicator (FUCCI). We also showed that proliferating cancer cells exist in a tumor only near nascent vessels or on the tumor surface as visualized with FUCCI and green fluorescent protein (GFP)-expressing tumor vessels. In the present study, we show the relationship between cell-cycle phase and chemotherapy-induced tumor angiogenesis using in vivo FUCCI real-time imaging of the cell cycle and nestin-driven GFP to detect nascent blood vessels. We observed that chemotherapy-treated tumors, consisting of mostly of quiescent cancer cells after treatment, had much more and deeper tumor vessels than untreated tumors. These newly-vascularized cancer cells regrew rapidly after chemotherapy. In contrast, formerly quiescent cancer cells decoyed to S/G2 phase by a telomerase-dependent adenovirus did not induce tumor angiogenesis. The present results further demonstrate the importance of the cancer-cell position in the cell cycle in order that chemotherapy be effective and not have the opposite effect of stimulating tumor angiogenesis and progression. PMID:27715464

  20. Expression of P-glycoprotein and multidrug resistance associated protein in Ehrlich ascites tumor cells after fractionated irradiation

    DEFF Research Database (Denmark)

    Nielsen, D; Maare, C; Eriksen, J

    2001-01-01

    PURPOSE: To characterize irradiated murine tumor cells with respect to drug resistance, drug kinetics, and ATPase activity, and to evaluate the possible role of P-glycoprotein (PGP) and murine multidrug resistance associated protein (Mrp1) in the drug-resistant phenotype of these cells. METHODS...... AND MATERIALS: Sensitive Ehrlich ascites tumor cells (EHR2) were in vitro exposed to fractionated irradiation (60 Gy). Western blot analysis was performed for determination of PGP and Mrp1, reverse transcriptase-polymerase chain reaction (RT-PCR) for determination of mdr1a + b mRNA, and semiquantitative RT......-PCR for Mrp1 mRNA. The clonogenic assay was applied to investigate sensitivity, whereas the steady-state drug accumulation of daunorubicin (DNR), 3H-vincristine (VCR), and 3H-etoposide (VP16) was measured by spectrofluorometry and scintillation counting, respectively. For determining of ATPase activity...

  1. Extravascular red blood cells and hemoglobin promote tumor growth and therapeutic resistance as endogenous danger signals.

    Science.gov (United States)

    Yin, Tao; He, Sisi; Liu, Xiaoling; Jiang, Wei; Ye, Tinghong; Lin, Ziqiang; Sang, Yaxiong; Su, Chao; Wan, Yang; Shen, Guobo; Ma, Xuelei; Yu, Min; Guo, Fuchun; Liu, Yanyang; Li, Ling; Hu, Qiancheng; Wang, Yongsheng; Wei, Yuquan

    2015-01-01

    Hemorrhage is a common clinical manifestation in patients with cancer. Intratumor hemorrhage has been demonstrated to be a poor prognostic factor for cancer patients. In this study, we investigated the role of RBCs and hemoglobin (Hb) in the process of tumor progression and therapeutical response. RBCs and Hb potently promoted tumor cell proliferation and syngenic tumor growth. RBCs and Hb activated the reactive oxygen species-NF-κB pathway in both tumor cells and macrophages. RBCs and Hb also induced chemoresistance mediated, in part, by upregulating ABCB1 gene expression. Tumor growth induced by RBCs was accompanied by an inflammatory signature, increased tumor vasculature, and influx of M2 macrophages. In both the peritoneal cavity and tumor microenvironment, extravascular RBCs rapidly recruited monocyte-macrophages into the lesion sites. In addition, RBCs and Hb increased several nucleotide-binding oligomerization domain-like receptors' expression and induced IL-1β release. Our results provide novel insights into the protumor function of RBCs and Hb as endogenous danger signals, which can promote tumor cell proliferation, macrophage recruitment, and polarization. Hemorrhage may represent a useful prognostic factor for cancer patients because of its role in tumor promotion and chemoresistance. Copyright © 2014 by The American Association of Immunologists, Inc.

  2. Overexpression of protein kinase A - RIalpha reduces lipofection efficiency of cisplatin-resistant human tumor cells.

    Science.gov (United States)

    Son, K K; Rosenblatt, J

    2001-04-10

    Cisplatin-resistant variant A2780CP/vector cells were 4.0-5.3-fold more transfectable and 7.6-fold more resistant to cisplatin than their parent cisplatin-sensitive human ovarian carcinoma A2780/vector cells. Overexpression of cAMP-dependent protein kinase Type I regulatory alpha subunit (PKA-RIalpha) gene in A2780CP cells significantly reduced (maximum 47.0%) the transfection activity, with a slight reduction (maximum 27.3%) of cisplatin resistance, of A2780CP cells. However, RIalpha-overexpressing A2780CP (A2780CP/RIalpha) cells were still 2.5-to 3.0-fold more transfectable and 5.5-fold more resistant to cisplatin than A2780 cells. This results suggest that gene transfer efficiency is associated with cisplatin resistance, in part, through the PKA-mediated cAMP signal transduction pathway.

  3. The PSA−/lo prostate cancer cell population harbors self-renewing long-term tumor-propagating cells that resist castration

    Science.gov (United States)

    Qin, Jichao; Liu, Xin; Laffin, Brian; Chen, Xin; Choy, Grace; Jeter, Collene; Calhoun-Davis, Tammy; Li, Hangwen; Palapattu, Ganesh S.; Pang, Shen; Lin, Kevin; Huang, Jiaoti; Ivanov, Ivan; Li, Wei; Suraneni, Mahipal V.; Tang, Dean G.

    2012-01-01

    SUMMARY Prostate cancer (PCa) is heterogeneous and contains both differentiated and undifferentiated tumor cells, but the relative functional contribution of these two cell populations remains unclear. Here we report distinct molecular, cellular, and tumor-propagating properties of PCa cells that express high (PSA+) and low (PSA−/lo) levels of the differentiation marker PSA. PSA−/lo PCa cells are quiescent and refractory to stresses including androgen deprivation, exhibit high clonogenic potential, and possess long-term tumor-propagating capacity. They preferentially express stem cell genes and can undergo asymmetric cell division generating PSA+ cells. Importantly, PSA−/lo PCa cells can initiate robust tumor development and resist androgen ablation in castrated hosts, and harbor highly tumorigenic castration-resistant PCa cells that can be prospectively enriched using ALDH+CD44+α2β1+ phenotype. In contrast, PSA+ PCa cells possess more limited tumor-propagating capacity, undergo symmetric division and are sensitive to castration. Together, our study suggests PSA−/lo cells may represent a critical source of castration-resistant PCa cells. PMID:22560078

  4. Phenotype switching : tumor cell plasticity as a resistance mechanism and target for therapy

    NARCIS (Netherlands)

    Kemper, K.; de Goeje, P.L.; Peeper, D.S.; van Amerongen, R.

    2014-01-01

    Mutations in BRAF are present in the majority of patients with melanoma, rendering these tumors sensitive to targeted therapy with BRAF and MEK inhibitors. Unfortunately, resistance almost invariably develops. Recently, a phenomenon called "phenotype switching" has been identified as an escape

  5. Human breast tumor cells are more resistant to cardiac glycoside toxicity than non-tumorigenic breast cells.

    Directory of Open Access Journals (Sweden)

    Rebecca J Clifford

    Full Text Available Cardiotonic steroids (CTS, specific inhibitors of Na,K-ATPase activity, have been widely used for treating cardiac insufficiency. Recent studies suggest that low levels of endogenous CTS do not inhibit Na,K-ATPase activity but play a role in regulating blood pressure, inducing cellular kinase activity, and promoting cell viability. Higher CTS concentrations inhibit Na,K-ATPase activity and can induce reactive oxygen species, growth arrest, and cell death. CTS are being considered as potential novel therapies in cancer treatment, as they have been shown to limit tumor cell growth. However, there is a lack of information on the relative toxicity of tumor cells and comparable non-tumor cells. We have investigated the effects of CTS compounds, ouabain, digitoxin, and bufalin, on cell growth and survival in cell lines exhibiting the full spectrum of non-cancerous to malignant phenotypes. We show that CTS inhibit membrane Na,K-ATPase activity equally well in all cell lines tested regardless of metastatic potential. In contrast, the cellular responses to the drugs are different in non-tumor and tumor cells. Ouabain causes greater inhibition of proliferation and more extensive apoptosis in non-tumor breast cells compared to malignant or oncogene-transfected cells. In tumor cells, the effects of ouabain are accompanied by activation of anti-apoptotic ERK1/2. However, ERK1/2 or Src inhibition does not sensitize tumor cells to CTS cytotoxicity, suggesting that other mechanisms provide protection to the tumor cells. Reduced CTS-sensitivity in breast tumor cells compared to non-tumor cells indicates that CTS are not good candidates as cancer therapies.

  6. F-Box Protein FBXO22 Mediates Polyubiquitination and Degradation of CD147 to Reverse Cisplatin Resistance of Tumor Cells.

    Science.gov (United States)

    Wu, Bo; Liu, Zhen-Yu; Cui, Jian; Yang, Xiang-Min; Jing, Lin; Zhou, Yang; Chen, Zhi-Nan; Jiang, Jian-Li

    2017-01-20

    Drug resistance remains a major clinical obstacle to successful treatment of cancer. As posttranslational modification is becoming widely recognized to affect the function of oncoproteins, targeting specific posttranslational protein modification provides an attractive strategy for anticancer drug development. CD147 is a transmembrane glycoprotein contributing to chemo-resistance of cancer cells in a variety of human malignancies. Ubiquitination is an important posttranslational modification mediating protein degradation. Degradation of oncoproteins, CD147 included, emerges as an attractive alternative for tumor inhibition. However, the ubiquitination of CD147 remains elusive. Here in this study, we found that deletion of the CD147 intracellular domain (CD147-ICD) prolonged the half-life of CD147 in HEK293T cells, and we identified that CD147-ICD interacts with FBXO22 using mass spectrometry and Western blot. Then, we demonstrated that FBXO22 mediates the polyubiquitination and degradation of CD147 by recognizing CD147-ICD. While knocking down of FBXO22 prolonged the half-life of CD147 in HEK293T cells, we found that FBXO22 regulates CD147 protein turnover in SMMC-7721, Huh-7 and A549 cells. Moreover, we found that the low level of FBXO22 contributes to the accumulation of CD147 and thereafter the cisplatin resistance of A549/DDP cells. To conclude, our study demonstrated that FBXO22 mediated the polyubiquitination and degradation of CD147 by interacting with CD147-ICD, and CD147 polyubiquitination by FBXO22 reversed cisplatin resistance of tumor cells.

  7. Transfer of allogeneic CD4+ T cells rescues CD8+ T cells in anti-PD-L1–resistant tumors leading to tumor eradication

    Science.gov (United States)

    Arina, Ainhoa; Karrison, Theodore; Galka, Eva; Schreiber, Karin; Weichselbaum, Ralph R.; Schreiber, Hans

    2017-01-01

    Adoptively transferred CD8+ T cells can stabilize the size of solid tumors over long periods of time by exclusively recognizing antigen cross-presented on tumor stroma. However, these tumors eventually escape T cell–mediated growth control. The aim of this study was to eradicate such persistent cancers. In our model, the SIYRYYGL antigen is expressed by cancer cells that lack the MHC-I molecule Kb needed for direct presentation, but the antigen is picked up and cross-presented by tumor stroma. A single injection of antigen-specific 2C CD8+ T cells caused long-term inhibition of tumor growth, but without further intervention, tumors started to progress after approximately 3 months. Escape was associated with reduced numbers of circulating 2C cells. Tumor-infiltrating 2C cells produced significantly less TNFα and expressed more of the “exhaustion” markers PD-1 and Tim-3 than T cells from lymphoid organs. High-dose local ionizing radiation, depletion of myeloid-derived suppressor cells, infusions of additional 2C cells, and antibodies blocking PD-L1 did not prevent tumor escape. In contrast, adoptive transfer of allogeneic CD4+ T cells restored the numbers of circulating Ag-specific CD8+ T cells and their intratumoral function, resulting in tumor eradication. These CD4+ T cells had no antitumor effects in the absence of CD8+ T cells and recognized the alloantigen cross-presented on tumor stroma. CD4+ T cells might also be effective in cancer patients when PD1/PD-L1 blockade does not rescue intratumoral CD8+ T-cell function and tumors persist. PMID:28077434

  8. Parallel selection of chemotherapy-resistant cell lines to illuminate mechanisms of drug resistance in human tumors

    DEFF Research Database (Denmark)

    Krzystanek, Marcin; Eklund, Aron Charles; Birkbak, Nicolai Juul

    2011-01-01

    Treatment of cancer often involves the use of chemotherapeutic agents that preferentially target tumor cells. The idea behind personalized medicine is to characterize differences between individual cancer cases that will and to direct the therapy to those most likely to respond. This will require...

  9. Allogeneic tumor cell vaccines

    Science.gov (United States)

    Srivatsan, Sanjay; Patel, Jaina M; Bozeman, Erica N; Imasuen, Imade E; He, Sara; Daniels, Danielle; Selvaraj, Periasamy

    2014-01-01

    The high mortality rate associated with cancer and its resistance to conventional treatments such as radiation and chemotherapy has led to the investigation of a variety of anti-cancer immunotherapies. The development of novel immunotherapies has been bolstered by the discovery of tumor-associated antigens (TAAs), through gene sequencing and proteomics. One such immunotherapy employs established allogeneic human cancer cell lines to induce antitumor immunity in patients through TAA presentation. Allogeneic cancer immunotherapies are desirable in a clinical setting due to their ease of production and availability. This review aims to summarize clinical trials of allogeneic tumor immunotherapies in various cancer types. To date, clinical trials have shown limited success due potentially to extensive degrees of inter- and intra-tumoral heterogeneity found among cancer patients. However, these clinical results provide guidance for the rational design and creation of more effective allogeneic tumor immunotherapies for use as monotherapies or in combination with other therapies. PMID:24064957

  10. Acquired IFNγ resistance impairs anti-tumor immunity and gives rise to T-cell-resistant melanoma lesions

    Science.gov (United States)

    Sucker, Antje; Zhao, Fang; Pieper, Natalia; Heeke, Christina; Maltaner, Raffaela; Stadtler, Nadine; Real, Birgit; Bielefeld, Nicola; Howe, Sebastian; Weide, Benjamin; Gutzmer, Ralf; Utikal, Jochen; Loquai, Carmen; Gogas, Helen; Klein-Hitpass, Ludger; Zeschnigk, Michael; Westendorf, Astrid M.; Trilling, Mirko; Horn, Susanne; Schilling, Bastian; Schadendorf, Dirk; Griewank, Klaus G.; Paschen, Annette

    2017-01-01

    Melanoma treatment has been revolutionized by antibody-based immunotherapies. IFNγ secretion by CD8+ T cells is critical for therapy efficacy having anti-proliferative and pro-apoptotic effects on tumour cells. Our study demonstrates a genetic evolution of IFNγ resistance in different melanoma patient models. Chromosomal alterations and subsequent inactivating mutations in genes of the IFNγ signalling cascade, most often JAK1 or JAK2, protect melanoma cells from anti-tumour IFNγ activity. JAK1/2 mutants further evolve into T-cell-resistant HLA class I-negative lesions with genes involved in antigen presentation silenced and no longer inducible by IFNγ. Allelic JAK1/2 losses predisposing to IFNγ resistance development are frequent in melanoma. Subclones harbouring inactivating mutations emerge under various immunotherapies but are also detectable in pre-treatment biopsies. Our data demonstrate that JAK1/2 deficiency protects melanoma from anti-tumour IFNγ activity and results in T-cell-resistant HLA class I-negative lesions. Screening for mechanisms of IFNγ resistance should be considered in therapeutic decision-making. PMID:28561041

  11. Anti-estrogen Resistance in Human Breast Tumors Is Driven by JAG1-NOTCH4-Dependent Cancer Stem Cell Activity

    Directory of Open Access Journals (Sweden)

    Bruno M. Simões

    2015-09-01

    Full Text Available Breast cancers (BCs typically express estrogen receptors (ERs but frequently exhibit de novo or acquired resistance to hormonal therapies. Here, we show that short-term treatment with the anti-estrogens tamoxifen or fulvestrant decrease cell proliferation but increase BC stem cell (BCSC activity through JAG1-NOTCH4 receptor activation both in patient-derived samples and xenograft (PDX tumors. In support of this mechanism, we demonstrate that high ALDH1 predicts resistance in women treated with tamoxifen and that a NOTCH4/HES/HEY gene signature predicts for a poor response/prognosis in 2 ER+ patient cohorts. Targeting of NOTCH4 reverses the increase in Notch and BCSC activity induced by anti-estrogens. Importantly, in PDX tumors with acquired tamoxifen resistance, NOTCH4 inhibition reduced BCSC activity. Thus, we establish that BCSC and NOTCH4 activities predict both de novo and acquired tamoxifen resistance and that combining endocrine therapy with targeting JAG1-NOTCH4 overcomes resistance in human breast cancers.

  12. S6Ks isoforms contribute to viability, migration, docetaxel resistance and tumor formation of prostate cancer cells

    International Nuclear Information System (INIS)

    Amaral, Camila L.; Freitas, Lidia B.; Tamura, Rodrigo E.; Tavares, Mariana R.; Pavan, Isadora C. B.; Bajgelman, Marcio C.; Simabuco, Fernando M.

    2016-01-01

    The S6 Kinase (S6K) proteins are some of the main downstream effectors of the mammalian Target Of Rapamycin (mTOR) and act as key regulators of protein synthesis and cell growth. S6K is overexpressed in a variety of human tumors and is correlated to poor prognosis in prostate cancer. Due to the current urgency to identify factors involved in prostate cancer progression, we aimed to reveal the cellular functions of three S6K isoforms–p70-S6K1, p85-S6K1 and p54-S6K2–in prostate cancer, as well as their potential as therapeutic targets. In this study we performed S6K knockdown and overexpression and investigated its role in prostate cancer cell proliferation, colony formation, viability, migration and resistance to docetaxel treatment. In addition, we measured tumor growth in Nude mice injected with PC3 cells overexpressing S6K isoforms and tested the efficacy of a new available S6K1 inhibitor in vitro. S6Ks overexpression enhanced PC3-luc cell line viability, migration, resistance to docetaxel and tumor formation in Nude mice. Only S6K2 knockdown rendered prostate cancer cells more sensitive to docetaxel. S6K1 inhibitor PF-4708671 was particularly effective for reducing migration and proliferation of PC3 cell line. These findings demonstrate that S6Ks play an important role in prostate cancer progression, enhancing cell viability, migration and chemotherapy resistance, and place both S6K1 and S6K2 as a potential targets in advanced prostate cancer. We also provide evidence that S6K1 inhibitor PF-4708671 may be considered as a potential drug for prostate cancer treatment. The online version of this article (doi:10.1186/s12885-016-2629-y) contains supplementary material, which is available to authorized users

  13. Expression of P-glycoprotein and multidrug resistance associated protein in Ehrlich ascites tumor cells after fractionated irradiation

    International Nuclear Information System (INIS)

    Nielsen, Dorte; Maare, Christian; Eriksen, Jens; Litman, Thomas; Skovsgaard, Torben

    2001-01-01

    Purpose: To characterize irradiated murine tumor cells with respect to drug resistance, drug kinetics, and ATPase activity, and to evaluate the possible role of P-glycoprotein (PGP) and murine multidrug resistance associated protein (Mrp1) in the drug-resistant phenotype of these cells. Methods and Materials: Sensitive Ehrlich ascites tumor cells (EHR2) were in vitro exposed to fractionated irradiation (60 Gy). Western blot analysis was performed for determination of PGP and Mrp1, reverse transcriptase-polymerase chain reaction (RT-PCR) for determination of mdr1a + b mRNA, and semiquantitative RT-PCR for Mrp1 mRNA. The clonogenic assay was applied to investigate sensitivity, whereas the steady-state drug accumulation of daunorubicin (DNR), 3 H-vincristine (VCR), and 3 H-etoposide (VP16) was measured by spectrofluorometry and scintillation counting, respectively. For determining of ATPase activity, the release of inorganic phosphate from ATP was quantified using a colorimetric method. Results: Compared with EHR2, the irradiated cell line EHR2/irr showed increased expression of PGP (threefold), Mrp1 (eightfold), and Mrp1 mRNA (sixfold), and a slight reduction of mdr1b mRNA, whereas mdr1a was present in EHR2 but could not be detected in EHR2/irr. EHR2/irr developed sixfold resistance to VP16, twofold resistance to vincristine, but remained sensitive to DNR. Addition of the PGP inhibitor, verapamil (VER) or depletion of glutathione by buthionine sulfoximine (BSO) partly reversed the resistance in EHR2/irr. In EHR2/irr, the steady-state accumulation of 3 H-VCR and 3 H-VP16 was significantly decreased as compared with EHR2, whereas the accumulation of DNR was unchanged. The ATPase activity of plasma membrane vesicles prepared from EHR2/irr cells was similar to that of wild-type EHR2 cells. The ATPase activity was neither stimulated by vinblastine nor VER. Conclusion: Irradiation induced a multidrug-resistant phenotype in sensitive tumor cells. This phenotype was

  14. NF-κB RelA renders tumor-associated macrophages resistant to and capable of directly suppressing CD8+ T cells for tumor promotion.

    Science.gov (United States)

    Li, Liwen; Han, Lei; Sun, Fan; Zhou, Jingjiao; Ohaegbulam, Kim C; Tang, Xudong; Zang, Xingxing; Steinbrecher, Kris A; Qu, Zhaoxia; Xiao, Gutian

    2018-01-01

    Activation of the inflammatory transcription factor NF-κB in tumor-associated macrophages (TAMs) is assumed to contribute to tumor promotion. However, whether and how NF-κB drives the antitumor macrophages to become pro-tumorigenic have not been determined in any cancer type yet. Similarly, how TAMs repress CD8 + cytotoxic T lymphocytes (CTLs) remains largely unknown, although their importance in regulatory T (Treg) cell regulation and tumor promotion has been well appreciated. Here, using an endogenous lung cancer model we uncover a direct crosstalk between TAMs and CTLs. TAMs suppress CTLs through the T-cell inhibitory molecule B7x (B7-H4/B7S1) in a cell-cell contact manner, whereas CTLs kill TAMs in a tumor antigen-specific manner. Remarkably, TAMs secrete the known T-cell suppressive cytokine interleukin-10 (IL-10) to activate, but not to repress, CTLs. Notably, one major role of cell-intrinsic NF-κB RelA is to drive TAMs to suppress CTLs for tumor promotion. It induces B7x expression in TAMs directly, and restricts IL-10 expression indirectly by repressing expression of the NF-κB cofactor Bcl3 and subsequent Bcl3/NF-κB1-mediated transcription of IL-10. It also renders TAMs resistant to CTLs by up-regulating anti-apoptotic genes. These studies help understand how immunity is shaped in lung tumorigenesis, and suggest a RelA-targeted immunotherapy for this deadliest cancer.

  15. The influence of the stem cell marker ALDH and the EGFR-PI3 kinase act signaling pathway on the radiation resistance of human tumor cell lines

    International Nuclear Information System (INIS)

    Mihatsch, Julia

    2014-01-01

    Cancer is the second leading cause of death in industriated nations. Besides surgery and chemotherapy, radiotherapy (RT) is an important approach by which about 60% of patients are treated. The response of these patients to RT is very heterogenous. On the one hand, there are patients with tumors which are radiosensitive and can be cured, but on the other hand patients bear tumors which are quite resistant to radiotherapy. A Radioresistant phenotype of tumor cells causes treatment failure consequently leading to a limited response to radiotherapy. It is proposed, that radiotherapy outcome mainly depends on the potential of radiation on controlling growth, proliferation and survival of a specific population of tumor cells called cancer stem cells (CSCs) or tumor-initiating cells. Based on experimental studies so far reported it is assumed that the population of CSC varies in tumors from different entities and is relatively low compared to the tumor bulk cells in general. According to the CSC hypothesis, it might be concluded that the differential response of tumors to radiotherapy depends on CSC populations, since these supposedly slow replicating cells are able to initiate a tumor, to self renew indefinitely and to generate the differentiated progeny of a tumor. Besides the role of cancer stem cells in radiotherapy response, ionizing radiation (IR) activates the epidermal growth factor receptor (EGFR) and its downstream signaling pathways such as phosphoinositide 3-kinase (PI3K)/Akt, mitogen-activated protein kinase (MAPK) and Janus kinase/Signal Transducer and Activator of Transcription (JAK/STAT) pathways. Among these pathways, PI3K/Akt is one of the most important pathways involved in post-irradiation survival: Activation of Akt results in activation of DNA-dependent protein kinase, catalytic subunit (DNA-PKcs). DNA-PKcs is a core enzyme involved in repair of IR-induced DNA-double strand breaks (DNA-DSB) through non-homologous end joining (NHEJ). The aim of the

  16. Laboratory determination of chemotherapeutic drug resistance in tumor cells from patients with leukemia, using a fluorometric microculture cytotoxicity assay (FMCA).

    Science.gov (United States)

    Larsson, R; Kristensen, J; Sandberg, C; Nygren, P

    1992-01-21

    An automated fluorometric microculture cytotoxicity assay (FMCA) based on the measurement of fluorescence generated from cellular hydrolysis of fluorescein diacetate (FDA) to fluorescein was employed for chemotherapeutic-drug-sensitivity testing of tumor-cell suspensions from patients with leukemia. Fluorescence was linearly related to cell number, and reproducible measurements of drug sensitivity could be performed using fresh or cryopreserved leukemia cells. A marked heterogeneity with respect to chemotherapeutic drug sensitivity was observed for a panel of cytotoxic drugs tested in 43 samples from 35 patients with treated or untreated acute and chronic leukemia. For samples obtained from patients with chronic lymphocytic and acute myelocytic leukemia, sensitivity profiles for standard drugs corresponded to known clinical activity and the assay detected primary and acquired drug resistance. Individual in vitro/in vivo correlations indicated high specificity with respect to the identification of drug resistance. The results suggest that the FMCA may be a simple and rapid method for in vivo-representative determinations of chemotherapeutic drug resistance in tumor cells obtained from patients with leukemia.

  17. Novel Imidazopyridine Derivatives Possess Anti-Tumor Effect on Human Castration-Resistant Prostate Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Matthew A Ingersoll

    Full Text Available Prostate cancer (PCa is the second leading cause of cancer-related death afflicting United States males. Most treatments to-date for metastatic PCa include androgen-deprivation therapy and second-generation anti-androgens such as abiraterone acetate and enzalutamide. However, a majority of patients eventually develop resistance to these therapies and relapse into the lethal, castration-resistant form of PCa to which no adequate treatment option remains. Hence, there is an immediate need to develop effective therapeutic agents toward this patient population. Imidazopyridines have recently been shown to possess Akt kinase inhibitory activity; thus in this study, we investigated the inhibitory effect of novel imidazopyridine derivatives HIMP, M-MeI, OMP, and EtOP on different human castration-resistant PCa cells. Among these compounds, HIMP and M-MeI were found to possess selective dose- and time-dependent growth inhibition: they reduced castration-resistant PCa cell proliferation and spared benign prostate epithelial cells. Using LNCaP C-81 cells as the model system, these compounds also reduced colony formation as well as cell adhesion and migration, and M-MeI was the most potent in all studies. Further investigation revealed that while HIMP primarily inhibits PCa cell growth via suppression of PI3K/Akt signaling pathway, M-MeI can inhibit both PI3K/Akt and androgen receptor pathways and arrest cell growth in the G2 phase. Thus, our results indicate the novel compound M-MeI to be a promising candidate for castration-resistant PCa therapy, and future studies investigating the mechanism of imidazopyridine inhibition may aid to the development of effective anti-PCa agents.

  18. Novel Imidazopyridine Derivatives Possess Anti-Tumor Effect on Human Castration-Resistant Prostate Cancer Cells.

    Science.gov (United States)

    Ingersoll, Matthew A; Lyons, Anastesia S; Muniyan, Sakthivel; D'Cunha, Napoleon; Robinson, Tashika; Hoelting, Kyle; Dwyer, Jennifer G; Bu, Xiu R; Batra, Surinder K; Lin, Ming-Fong

    2015-01-01

    Prostate cancer (PCa) is the second leading cause of cancer-related death afflicting United States males. Most treatments to-date for metastatic PCa include androgen-deprivation therapy and second-generation anti-androgens such as abiraterone acetate and enzalutamide. However, a majority of patients eventually develop resistance to these therapies and relapse into the lethal, castration-resistant form of PCa to which no adequate treatment option remains. Hence, there is an immediate need to develop effective therapeutic agents toward this patient population. Imidazopyridines have recently been shown to possess Akt kinase inhibitory activity; thus in this study, we investigated the inhibitory effect of novel imidazopyridine derivatives HIMP, M-MeI, OMP, and EtOP on different human castration-resistant PCa cells. Among these compounds, HIMP and M-MeI were found to possess selective dose- and time-dependent growth inhibition: they reduced castration-resistant PCa cell proliferation and spared benign prostate epithelial cells. Using LNCaP C-81 cells as the model system, these compounds also reduced colony formation as well as cell adhesion and migration, and M-MeI was the most potent in all studies. Further investigation revealed that while HIMP primarily inhibits PCa cell growth via suppression of PI3K/Akt signaling pathway, M-MeI can inhibit both PI3K/Akt and androgen receptor pathways and arrest cell growth in the G2 phase. Thus, our results indicate the novel compound M-MeI to be a promising candidate for castration-resistant PCa therapy, and future studies investigating the mechanism of imidazopyridine inhibition may aid to the development of effective anti-PCa agents.

  19. Hypoxia-induced tumor cell resistance is overcome by synergistic GAPDH-siRNA and chemotherapy co-delivered by long-circulating and cationic-interior liposomes

    NARCIS (Netherlands)

    Guan, J.; Sun, J.; Sun, F.; Lou, B.; Zhang, D.; Mashayekhi, V.; Sadeghi, N.; Storm, G.; Mastrobattista, E.; He, Z.

    2017-01-01

    Chemotherapeutic drug resistance of tumor cells under hypoxic conditions is caused by the inhibition of apoptosis by autophagy and drug efflux via adenosine triphosphate (ATP)-dependent transporter activation, among other factors. Here, we demonstrate that disrupting glyceraldehyde-3-phosphate

  20. Phenotypic and genetic heterogeneity of tumor tissue and circulating tumor cells in patients with metastatic castration-resistant prostate cancer: A report from the PETRUS prospective study.

    Science.gov (United States)

    Massard, Christophe; Oulhen, Marianne; Le Moulec, Sylvestre; Auger, Nathalie; Foulon, Stéphanie; Abou-Lovergne, Aurélie; Billiot, Fanny; Valent, Alexander; Marty, Virginie; Loriot, Yohann; Fizazi, Karim; Vielh, Philippe; Farace, Francoise

    2016-08-23

    Molecular characterization of cancer samples is hampered by tumor tissue availability in metastatic castration-resistant prostate cancer (mCRPC) patients. We reported the results of prospective PETRUS study of biomarker assessment in paired primary prostatic tumors, metastatic biopsies and circulating tumor cells (CTCs). Among 54 mCRPC patients enrolled, 38 (70%) had biopsies containing more than 50% tumour cells. 28 (52%) patients were analyzed for both tissue samples and CTCs. FISH for AR-amplification and TMPRSS2-ERG translocation were successful in 54% and 32% in metastatic biopsies and primary tumors, respectively. By comparing CellSearch and filtration (ISET)-enrichment combined to four color immunofluorescent staining, we showed that CellSearch and ISET isolated distinct subpopulations of CTCs: CTCs undergoing epithelial-to-mesenchymal transition, CTC clusters and large CTCs with cytomorphological characteristics but no detectable markers were isolated using ISET. Epithelial CTCs detected by the CellSearch were mostly lost during the ISET-filtration. AR-amplification was detected in CellSearch-captured CTCs, but not in ISET-enriched CTCs which harbor exclusively AR gain of copies. Eighty-eight percent concordance for ERG-rearrangement was observed between metastatic biopsies and CTCs even if additional ERG-alteration patterns were detected in ISET-enriched CTCs indicating a higher heterogeneity in CTCs.Molecular screening of metastatic biopsies is achievable in a multicenter context. Our data indicate that CTCs detected by the CellSearch and the ISET-filtration systems are not only phenotypically but also genetically different. Close attention must be paid to CTC characterization since neither approach tested here fully reflects the tremendous phenotypic and genetic heterogeneity present in CTCs from mCRPC patients.

  1. Combination of Bifunctional Alkylating Agent and Arsenic Trioxide Synergistically Suppresses the Growth of Drug-Resistant Tumor Cells

    Directory of Open Access Journals (Sweden)

    Pei-Chih Lee

    2010-05-01

    Full Text Available Drug resistance is a crucial factor in the failure of cancer chemotherapy. In this study, we explored the effect of combining alkylating agents and arsenic trioxide (ATO on the suppression of tumor cells with inherited or acquired resistance to therapeutic agents. Our results showed that combining ATO and a synthetic derivative of 3a-aza-cyclopenta[a]indenes (BO-1012, a bifunctional alkylating agent causing DNA interstrand cross-links, was more effective in killing human cancer cell lines (H460, H1299, and PC3 than combining ATO and melphalan or thiotepa. We further demonstrated that the combination treatment of H460 cells with BO-1012 and ATO resulted in severe G2/M arrest and apoptosis. In a xenograft mouse model, the combination treatment with BO-1012 and ATO synergistically reduced tumor volumes in nude mice inoculated with H460 cells. Similarly, the combination of BO-1012 and ATO effectively reduced the growth of cisplatin-resistant NTUB1/P human bladder carcinoma cells. Furthermore, the repair of BO-1012-induced DNA interstrand cross-links was significantly inhibited by ATO, and consequently, γH2AX was remarkably increased and formed nuclear foci in H460 cells treated with this drug combination. In addition, Rad51 was activated by translocating and forming foci in nuclei on treatment with BO-1012, whereas its activation was significantly suppressed by ATO. We further revealed that ATO might mediate through the suppression of AKT activity to inactivate Rad51. Taken together, the present study reveals that a combination of bifunctional alkylating agents and ATO may be a rational strategy for treating cancers with inherited or acquired drug resistance.

  2. F-Box Protein FBXO22 Mediates Polyubiquitination and Degradation of CD147 to Reverse Cisplatin Resistance of Tumor Cells

    Directory of Open Access Journals (Sweden)

    Bo Wu

    2017-01-01

    Full Text Available Drug resistance remains a major clinical obstacle to successful treatment of cancer. As posttranslational modification is becoming widely recognized to affect the function of oncoproteins, targeting specific posttranslational protein modification provides an attractive strategy for anticancer drug development. CD147 is a transmembrane glycoprotein contributing to chemo-resistance of cancer cells in a variety of human malignancies. Ubiquitination is an important posttranslational modification mediating protein degradation. Degradation of oncoproteins, CD147 included, emerges as an attractive alternative for tumor inhibition. However, the ubiquitination of CD147 remains elusive. Here in this study, we found that deletion of the CD147 intracellular domain (CD147-ICD prolonged the half-life of CD147 in HEK293T cells, and we identified that CD147-ICD interacts with FBXO22 using mass spectrometry and Western blot. Then, we demonstrated that FBXO22 mediates the polyubiquitination and degradation of CD147 by recognizing CD147-ICD. While knocking down of FBXO22 prolonged the half-life of CD147 in HEK293T cells, we found that FBXO22 regulates CD147 protein turnover in SMMC-7721, Huh-7 and A549 cells. Moreover, we found that the low level of FBXO22 contributes to the accumulation of CD147 and thereafter the cisplatin resistance of A549/DDP cells. To conclude, our study demonstrated that FBXO22 mediated the polyubiquitination and degradation of CD147 by interacting with CD147-ICD, and CD147 polyubiquitination by FBXO22 reversed cisplatin resistance of tumor cells.

  3. Are lipid rafts involved in ABC transporter-mediated drug resistance of tumor cells?

    NARCIS (Netherlands)

    Kok, Jan Willem; Klappe, Karin; Hummel, Ina; Kroesen, Bart-Jan; Sietsma, Hannie; Meszaros, Peter

    2008-01-01

    Since their discovery, lipid rafts have been implicated in several cellular functions, including protein transport in polarized cells and signal transduction. Also in multidrug resistance lipid rafts may be important with regard to the localization of ATP-binding cassette (ABC) transporters in these

  4. Oridonin Targets Multiple Drug-Resistant Tumor Cells as Determined by in Silico and in Vitro Analyses

    Directory of Open Access Journals (Sweden)

    Onat Kadioglu

    2018-04-01

    Full Text Available Drug resistance is one of the main reasons of chemotherapy failure. Therefore, overcoming drug resistance is an invaluable approach to identify novel anticancer drugs that have the potential to bypass or overcome resistance to established drugs and to substantially increase life span of cancer patients for effective chemotherapy. Oridonin is a cytotoxic diterpenoid isolated from Rabdosia rubescens with in vivo anticancer activity. In the present study, we evaluated the cytotoxicity of oridonin toward a panel of drug-resistant cancer cells overexpressing ABCB1, ABCG2, or ΔEGFR or with a knockout deletion of TP53. Interestingly, oridonin revealed lower degree of resistance than the control drug, doxorubicin. Molecular docking analyses pointed out that oridonin can interact with Akt/EGFR pathway proteins with comparable binding energies and similar docking poses as the known inhibitors. Molecular dynamics results validated the stable conformation of oridonin docking pose on Akt kinase domain. Western blot experiments clearly revealed dose-dependent downregulation of Akt and STAT3. Pharmacogenomics analyses pointed to a mRNA signature that predicted sensitivity and resistance to oridonin. In conclusion, oridonin bypasses major drug resistance mechanisms and targets Akt pathway and might be effective toward drug refractory tumors. The identification of oridonin-specific gene expressions may be useful for the development of personalized treatment approaches.

  5. Betulinic Acid Exerts Cytotoxic Activity Against Multidrug-Resistant Tumor Cells via Targeting Autocrine Motility Factor Receptor (AMFR

    Directory of Open Access Journals (Sweden)

    Mohamed E. M. Saeed

    2018-05-01

    Full Text Available Betulinic acid (BetA is a naturally occurring pentacyclic triterpene isolated from the outer bark of white-barked birch trees and many other medicinal plants. Here, we studied betulinic acid's cytotoxic activity against drug-resistant tumor cell lines. P-glycoprotein (MDR1/ABCB1 and BCRP (ABCG2 are known ATP-binding cassette (ABC drug transporters that mediating MDR. ABCB5 is a close relative to ABCB1, which also mediates MDR. Constitutive activation of the EGF receptor is tightly linked to the development of chemotherapeutic resistance. BetA inhibited P-gp, BCRP, ABCB5 and mutation activated EGFR overexpressing cells with similar efficacy as their drug-sensitive parental counterparts. Furthermore, the mRNA expressions of ABCB1, BCRP, ABCB5 and EGFR were not related to the 50% inhibition concentrations (IC50 for BetA in a panel of 60 cell lines of the National Cancer Institute (NCI, USA. In addition to well-established MDR mechanisms, we attempted to identify other molecular mechanisms that play a role in mediating BetA's cytotoxic activity. For this reason, we performed COMPARE and hierarchical cluster analyses of the transcriptome-wide microarray-based mRNA expression of the NCI cell lines panel. Various genes significantly correlating to BetA's activity were involved in different biological processes, e.g., cell cycle regulation, microtubule formation, signal transduction, transcriptional regulation, chromatin remodeling, cell adhesion, tumor suppression, ubiquitination and proteasome degradation. Immunoblotting and in silico analyses revealed that the inhibition of AMFR activity might be one of the mechanisms for BetA to overcome MDR phenotypes. In conclusion, BetA may have therapeutic potential for the treatment of refractory tumors.

  6. Ectopic expression of X-linked lymphocyte-regulated protein pM1 renders tumor cells resistant to antitumor immunity.

    Science.gov (United States)

    Kang, Tae Heung; Noh, Kyung Hee; Kim, Jin Hee; Bae, Hyun Cheol; Lin, Ken Y; Monie, Archana; Pai, Sara I; Hung, Chien-Fu; Wu, T-C; Kim, Tae Woo

    2010-04-15

    Tumor immune escape is a major obstacle in cancer immunotherapy, but the mechanisms involved remain poorly understood. We have previously developed an immune evasion tumor model using an in vivo immune selection strategy and revealed Akt-mediated immune resistance to antitumor immunity induced by various cancer immunotherapeutic agents. In the current study, we used microarray gene analysis to identify an Akt-activating candidate molecule overexpressed in immune-resistant tumors compared with parental tumors. X-linked lymphocyte-regulated protein pM1 (XLR) gene was the most upregulated in immune-resistant tumors compared with parental tumor cells. Furthermore, the retroviral transduction of XLR in parental tumor cells led to activation of Akt, resulting in upregulation of antiapoptotic proteins and the induction of immune resistance phenotype in parental tumor cells. In addition, we found that transduction of parental tumor cells with other homologous genes from the mouse XLR family, such as synaptonemal complex protein 3 (SCP3) and XLR-related, meiosis-regulated protein (XMR) and its human counterpart of SCP3 (hSCP3), also led to activation of Akt, resulting in the upregulation of antiapoptotic proteins and induction of immune resistance phenotype. Importantly, characterization of a panel of human cervical cancers revealed relatively higher expression levels of hSCP3 in human cervical cancer tissue compared with normal cervical tissue. Thus, our data indicate that ectopic expression of XLR and its homologues in tumor cells represents a potentially important mechanism for tumor immune evasion and serves as a promising molecular target for cancer immunotherapy. (c) 2010 AACR.

  7. Cytotoxic effect of essential oil of thyme (Thymus broussonettii on the IGR-OV1 tumor cells resistant to chemotherapy

    Directory of Open Access Journals (Sweden)

    L. Ait M'Barek

    2007-11-01

    Full Text Available The anti-tumor effect of the Moroccan endemic thyme (Thymus broussonettii essential oil (EOT was investigated in vitro using the human ovarian adenocarcinoma IGR-OV1 parental cell line OV1/P and its chemoresistant counterparts OV1/adriamycin (OV1/ADR, OV1/vincristine (OV1/VCR, and OV1/cisplatin (OV1/CDDP. All of these cell lines elicited various degrees of sensitivity to the cytotoxic effect of EOT. The IC50 values (mean ± SEM, v/v were 0.40 ± 0.02, 0.39 ± 0.02, 0.94 ± 0.05, and 0.65 ± 0.03% for OV1/P, OV1/ADR, OV1/VCR, and OV1/CDDP, respectively. Using the DBA-2/P815 (H2d mouse model, tumors were developed by subcutaneous grafting of tumor fragments of similar size obtained from P815 (murin mastocytoma cell line injected in donor mouse. Interestingly, intra-tumoral injection of EOT significantly reduced solid tumor development. Indeed, by the 30th day of repeated EOT treatment, the tumor volumes of the animals were 2.00 ± 0.27, 1.35 ± 0.20, and 0.85 ± 0.18 cm³ after injection with 10, 30, or 50 µL per 72 h (six times, respectively, as opposed to 3.88 ± 0.50 cm³ for the control animals. This tumoricidal effect was associated with a marked decrease of mouse mortality. In fact, in these groups of mice, the recorded mortality by the 30th day of treatment was 30 ± 4, 18 ± 4, and 8 ± 3%, respectively, while the control animals showed 75 ± 10% of mortality. These data indicate that the EOT which contains carvacrol as the major component has an important in vitro cytotoxic activity against tumor cells resistant to chemotherapy as well as a significant antitumor effect in mice. However, our data do not distinguish between carvacrol and the other components of EOT as the active factor.

  8. Acquired Tumor Cell Radiation Resistance at the Treatment Site Is Mediated Through Radiation-Orchestrated Intercellular Communication

    Energy Technology Data Exchange (ETDEWEB)

    Aravindan, Natarajan, E-mail: naravind@ouhsc.edu [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Aravindan, Sheeja; Pandian, Vijayabaskar; Khan, Faizan H.; Ramraj, Satish Kumar; Natt, Praveen [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Natarajan, Mohan [Department of Pathology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas (United States)

    2014-03-01

    Purpose: Radiation resistance induced in cancer cells that survive after radiation therapy (RT) could be associated with increased radiation protection, limiting the therapeutic benefit of radiation. Herein we investigated the sequential mechanistic molecular orchestration involved in radiation-induced radiation protection in tumor cells. Results: Radiation, both in the low-dose irradiation (LDIR) range (10, 50, or 100 cGy) or at a higher, challenge dose IR (CDIR), 4 Gy, induced dose-dependent and sustained NFκB-DNA binding activity. However, a robust and consistent increase was seen in CDIR-induced NFκB activity, decreased DNA fragmentation, apoptosis, and cytotoxicity and attenuation of CDIR-inhibited clonal expansion when the cells were primed with LDIR prior to challenge dose. Furthermore, NFκB manipulation studies with small interfering RNA (siRNA) silencing or p50/p65 overexpression unveiled the influence of LDIR-activated NFκB in regulating CDIR-induced DNA fragmentation and apoptosis. LDIR significantly increased the transactivation/translation of the radiation-responsive factors tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), cMYC, and SOD2. Coculture experiments exhibit LDIR-influenced radiation protection and increases in cellular expression, secretion, and activation of radiation-responsive molecules in bystander cells. Individual gene-silencing approach with siRNAs coupled with coculture studies showed the influence of LDIR-modulated TNF-α, IL-1α, cMYC, and SOD2 in induced radiation protection in bystander cells. NFκB inhibition/overexpression studies coupled with coculture experiments demonstrated that TNF-α, IL-1α, cMYC, and SOD2 are selectively regulated by LDIR-induced NFκB. Conclusions: Together, these data strongly suggest that scattered LDIR-induced NFκB-dependent TNF-α, IL-1α, cMYC, and SOD2 mediate radiation protection to the subsequent challenge dose in tumor cells.

  9. Cytotoxicity and apoptosis induced by alfalfa (Medicago sativa) leaf extracts in sensitive and multidrug-resistant tumor cells.

    Science.gov (United States)

    Gatouillat, Grégory; Magid, Abdulmagid Alabdul; Bertin, Eric; Okiemy-Akeli, Marie-Genevieve; Morjani, Hamid; Lavaud, Catherine; Madoulet, Claudie

    2014-01-01

    Alfalfa (Medicago sativa) has been used to cure a wide variety of ailments. However, only a few studies have reported its anticancer effects. In this study, extracts were obtained from alfalfa leaves and their cytotoxic effects were assessed on several sensitive and multidrug-resistant tumor cells lines. Using the mouse leukaemia P388 cell line and its doxorubicin-resistant counterpart (P388/DOX), we showed that the inhibition of cell growth induced by alfalfa leaf extracts was mediated through the induction of apoptosis, as evidenced by DNA fragmentation analysis. The execution of programmed cell death was achieved via the activation of caspase-3, leading to PARP cleavage. Fractionation of toluene extract (To-1), the most active extract obtained from crude extract, led to the identification of 3 terpene derivatives and 5 flavonoids. Among them, (-)-medicarpin, (-)-melilotocarpan E, millepurpan, tricin, and chrysoeriol showed cytotoxic effects in P388 as well as P388/DOX cells. These results demonstrate that alfalfa leaf extract may have interesting potential in cancer chemoprevention and therapy.

  10. A study of radiation sensitivity and drug-resistance by DNA methylation in human tumor cell lines

    International Nuclear Information System (INIS)

    Jung, Il Lae; Kim, In Gyu; Kim, Kug Chan

    2009-12-01

    It has recently been known that functional loss of tumor suppressive genes may com from DNA methylation on the chromosome. This kind of tumorigenesis has became one of the major field related to the epigenetics, whose study would be an important fundamental approach in cancer therapy market. In this study, we firstly selected two radiation-resistant mutant H460 cells, which doesn't show any significant cytotoxic effect compared to their parental wild type H460. We found that the two mutants has decreased level of PTEN, whose expression has known to be related to the cell differentiation and growth. We also found that the level of PTEN was greatly different in two lung adenocarcinoma, H460 and A549, in which more radiation-resistant A549 cells showed the decreased PTEN expression. This difference in PTEN expression between two cells was resulted from their different methylation on 5 CpG islands. We expect to know more profoundly through investigating the PTEN-related downstream genes

  11. Lung cancer tumorigenicity and drug resistance are maintained through ALDH(hi)CD44(hi) tumor initiating cells.

    Science.gov (United States)

    Liu, Jing; Xiao, Zhijie; Wong, Sunny Kit-Man; Tin, Vicky Pui-Chi; Ho, Ka-Yan; Wang, Junwen; Sham, Mai-Har; Wong, Maria Pik

    2013-10-01

    Limited improvement in long term survival of lung cancer patients has been achieved by conventional chemotherapy or targeted therapy. To explore the potentials of tumor initiating cells (TIC)-directed therapy, it is essential to identify the cell targets and understand their maintenance mechanisms. We have analyzed the performance of ALDH/CD44 co-expression as TIC markers and treatment targets of lung cancer using well-validated in vitro and in vivo analyses in multiple established and patient-derived lung cancer cells. The ALDH(hi)CD44(hi) subset showed the highest enhancement of stem cell phenotypic properties compared to ALDH(hi)CD44(lo), ALDH(lo)CD44(hi), ALDH(lo)CD44(lo) cells and unsorted controls. They showed higher invasion capacities, pluripotency genes and epithelial-mesenchymal transition transcription factors expression, lower intercellular adhesion protein expression and higher G2/M phase cell cycle fraction. In immunosuppressed mice, the ALDH(hi)CD44(hi)xenografts showed the highest tumor induction frequency, serial transplantability, shortest latency, largest volume and highest growth rates. Inhibition of sonic Hedgehog and Notch developmental pathways reduced ALDH+CD44+ compartment. Chemotherapy and targeted therapy resulted in higher AALDH(hi)CD44(hi) subset viability and ALDH(lo)CD44(lo) subset apoptosis fraction. ALDH inhibition and CD44 knockdown led to reduced stemness gene expression and sensitization to drug treatment. In accordance, clinical lung cancers containing a higher abundance of ALDH and CD44-coexpressing cells was associated with lower recurrence-free survival. Together, results suggested theALDH(hi)CD44(hi)compartment was the cellular mediator of tumorigenicity and drug resistance. Further investigation of the regulatory mechanisms underlying ALDH(hi)CD44(hi)TIC maintenance would be beneficial for the development of long term lung cancer control.

  12. Cytoplasmic superoxide dismutase and catalase activity and resistance to radiation lethality in murine tumor cells

    International Nuclear Information System (INIS)

    Davy, C.A.; Tesfay, Z.; Jones, J.; Rosenberg, R.C.; McCarthy, C.; Rosenberg, S.O.

    1986-01-01

    Reduced species of molecular oxygen are produced by the interaction of ionizing radiation with aqueous solutions containing molecular oxygen. The enzymes catalase and superoxide dismutase (SOD) are thought to function in vivo as scavengers of metabolically produced peroxide and superoxide respectively. SOD has been shown to protect against the lethal effects of ionizing radiation in vitro and in vivo. The authors have investigated the relationship between the cytosolic SOD catalase content and the sensitivity to radiation lethality of a number of murine cell lines (402AX, EL-4, MB-2T3, MB-4, MEL, P-815, SAI, SP-2, and SV-3T3). K/sub i/(CN - ) for murine Cu-Zn-SOD was determined to be 6.8 x 10 -6 M. No cytosolic Mn-SOD activity was found in any of the cell lines studied. No correlation was found between the cytosolic Cu-Zn-SOD or cytosolic catalase activity and the resistance to radiation lethality or the murine cell lines studied

  13. Resistance of tumor cells to hydrogen peroxide as a factor of selection of highly metastatic cell variants in vivo

    International Nuclear Information System (INIS)

    Deichman, G.I.; Vendrov, E.L.

    1986-01-01

    The authors investigate the theory that tumor cells which catabolize H 2 O 2 more actively may possibly have selected advantages in vivo (of different origin). The authors tested the sensitivity to H 2 O 2 of parental cells of strain STHE (which did not progress in vivo) and 17 of its daughter variants isolated from lung tissue of experimental animals at different stages of formation of metastases (before and after their formation) and differing in metastatic activity. Intact cells were placed into test tube No. 6 of each series. After 30 min of exposure at 20 0 C, cells treated with H 2 O 2 and intact cells were washed out by centrifugation, and resuspended in nutritive medium containing 10% bovine serum and 3 H-thymidine, and each sample was diffused at a volume of 2.0 ml of cell suspension in each of three scintillation vials. The proliferative pool of cells in each sample was determined according to incorporation (for 22 h at 37 0 C) of 3 H-thymidine into cell nuclei. Data concerning incorporation of 3 H-thymidine was expressed for each sample of cells in percentages in relation to corresponding intact control (incorporation of label in a control culture of intact cells was taken as 100%). Each cell variant was investigated repeatedly in two-three more experiments

  14. Metaphyseal giant cell tumor

    International Nuclear Information System (INIS)

    Pereira, L.F.; Hemais, P.M.P.G.; Aymore, I.L.; Carmo, M.C.R. do; Cunha, M.E.P.R. da; Resende, C.M.C.

    1986-01-01

    Three cases of metaphyseal giant cell tumor are presented. A review of the literature is done, demostrating the lesion is rare and that there are few articles about it. Age incidence and characteristics of the tumor are discussed. (Author) [pt

  15. The hypoxic tumor microenvironment and drug resistance against EGFR inhibitors: preclinical study in cetuximab-sensitive head and neck squamous cell carcinoma cell lines.

    Science.gov (United States)

    Boeckx, Carolien; Van den Bossche, Jolien; De Pauw, Ines; Peeters, Marc; Lardon, Filip; Baay, Marc; Wouters, An

    2015-06-02

    Increased expression of the epidermal growth factor receptor (EGFR) is observed in more than 90% of all head and neck squamous cell carcinomas (HNSCC). Therefore, EGFR has emerged as a promising therapeutic target. Nevertheless, drug resistance remains a major challenge and an important potential mechanism of drug resistance involves the hypoxic tumor microenvironment. Therefore, we investigated the cytotoxic effect of the EGFR-targeting agents cetuximab and erlotinib under normoxia versus hypoxia. Three cetuximab-sensitive HNSCC cell lines (SC263, LICR-HN2 and LICR-HN5) were treated with either cetuximab or erlotinib. Cells were incubated under normal or reduced oxygen conditions (<0.1% O2) for 24 or 72 h immediately after drug addition. Cell survival was assessed with the sulforhodamine B assay. Cetuximab and erlotinib established a dose-dependent growth inhibition under both normal and prolonged reduced oxygen conditions in all three HNSCC cell lines. However, a significantly increased sensitivity to cetuximab was observed in SC263 cells exposed to hypoxia for 72 h (p = 0.05), with IC50 values of 2.38 ± 0.59 nM, 0.64 ± 0.38 nM, and 0.10 ± 0.05 nM under normoxia, hypoxia for 24 h and hypoxia for 72 h, respectively. LICR-HN5 cells showed an increased sensitivity towards erlotinib when cells were incubated under hypoxia for 24 h (p = 0.05). Our results suggest that both EGFR-inhibitors cetuximab and erlotinib maintain their growth inhibitory effect under hypoxia. These results suggest that resistance to anti-EGFR therapy in HNSCC is probably not the result of hypoxic regions within the tumor and other mechanisms are involved.

  16. MicroRNA Expression Profiles Associated with Development of Drug Resistance in Ehrlich Ascites Tumor Cells

    DEFF Research Database (Denmark)

    Husted, Susanne; Søkilde, Rolf; Rask, Lene

    2011-01-01

    Multidrug resistance (MDR) poses a major obstacle to successful chemotherapeutic treatment of cancer, and often involves multiple genes, which may be regulated post-transcriptionally by microRNAs (miRNAs). The purpose of the present study was therefore to identify any resistance-associated change...

  17. Tumor cell surface proteins

    International Nuclear Information System (INIS)

    Kennel, S.J.; Braslawsky, G.R.; Flynn, K.; Foote, L.J.; Friedman, E.; Hotchkiss, J.A.; Huang, A.H.L.; Lankford, P.K.

    1982-01-01

    Cell surface proteins mediate interaction between cells and their environment. Unique tumor cell surface proteins are being identified and quantified in several tumor systems to address the following questions: (i) how do tumor-specific proteins arise during cell transformation; (ii) can these proteins be used as markers of tumor cell distribution in vivo; (iii) can cytotoxic drugs be targeted specifically to tumor cells using antibody; and (iv) can solid state radioimmunoassay of these proteins provide a means to quantify transformation frequencies. A tumor surface protein of 180,000 M/sub r/ (TSP-180) has been identified on cells of several lung carcinomas of BALB/c mice. TSP-180 was not detected on normal lung tissue, embryonic tissue, or other epithelial or sarcoma tumors, but it was found on lung carcinomas of other strains of mice. Considerable amino acid sequence homology exists among TSP-180's from several cell sources, indicating that TSP-180 synthesis is directed by normal cellular genes although it is not expressed in normal cells. The regulation of synthesis of TSP-180 and its relationship to normal cell surface proteins are being studied. Monoclonal antibodies (MoAb) to TSP-180 have been developed. The antibodies have been used in immunoaffinity chromatography to isolate TSP-180 from tumor cell sources. This purified tumor antigen was used to immunize rats. Antibody produced by these animals reacted at different sites (epitopes) on the TSP-180 molecule than did the original MoAb. These sera and MoAb from these animals are being used to identify normal cell components related to the TSP-180 molecule

  18. Determinates of tumor response to radiation: Tumor cells, tumor stroma and permanent local control

    International Nuclear Information System (INIS)

    Li, Wende; Huang, Peigen; Chen, David J.; Gerweck, Leo E.

    2014-01-01

    Background and purpose: The causes of tumor response variation to radiation remain obscure, thus hampering the development of predictive assays and strategies to decrease resistance. The present study evaluates the impact of host tumor stromal elements and the in vivo environment on tumor cell kill, and relationship between tumor cell radiosensitivity and the tumor control dose. Material and methods: Five endpoints were evaluated and compared in a radiosensitive DNA double-strand break repair-defective (DNA-PKcs −/− ) tumor line, and its DNA-PKcs repair competent transfected counterpart. In vitro colony formation assays were performed on in vitro cultured cells, on cells obtained directly from tumors, and on cells irradiated in situ. Permanent local control was assessed by the TCD 50 assay. Vascular effects were evaluated by functional vascular density assays. Results: The fraction of repair competent and repair deficient tumor cells surviving radiation did not substantially differ whether irradiated in vitro, i.e., in the absence of host stromal elements and factors, from the fraction of cells killed following in vivo irradiation. Additionally, the altered tumor cell sensitivity resulted in a proportional change in the dose required to achieve permanent local control. The estimated number of tumor cells per tumor, their cloning efficiency and radiosensitivity, all assessed by in vitro assays, were used to predict successfully, the measured tumor control doses. Conclusion: The number of clonogens per tumor and their radiosensitivity govern the permanent local control dose

  19. Interaction of tumor cells with the microenvironment

    Directory of Open Access Journals (Sweden)

    Lehnert Hendrik

    2011-09-01

    Full Text Available Abstract Recent advances in tumor biology have revealed that a detailed analysis of the complex interactions of tumor cells with their adjacent microenvironment (tumor stroma is mandatory in order to understand the various mechanisms involved in tumor growth and the development of metastasis. The mutual interactions between tumor cells and cellular and non-cellular components (extracellular matrix = ECM of the tumor microenvironment will eventually lead to a loss of tissue homeostasis and promote tumor development and progression. Thus, interactions of genetically altered tumor cells and the ECM on the one hand and reactive non-neoplastic cells on the other hand essentially control most aspects of tumorigenesis such as epithelial-mesenchymal-transition (EMT, migration, invasion (i.e. migration through connective tissue, metastasis formation, neovascularisation, apoptosis and chemotherapeutic drug resistance. In this mini-review we will focus on these issues that were recently raised by two review articles in CCS.

  20. Effects of combinations of chemotherapy and radiation on the emergence of drug resistant cells in 9L rat brain tumor spheroids

    International Nuclear Information System (INIS)

    Tofilon, P.J.; Arundel, C.; Vines, C.M.

    1987-01-01

    Repeated administration of antineoplastic chemotherapeutic agents is generally considered to induce and/or select for drug resistant cells. The authors recently begun to investigate whether chemotherapy interdigitated with radiation can minimize or eliminate the emergence of drug resiistent cells in 9L rat brain tumor spheroids grown from defined mixtures of cells sensitive (9L) and resistant (R/sub 3/) to BCNU. In this experimental system, the sister chromatid exchange (SCE) assay is used to quantitate the proportions of sensitive and resistant cells within the spheroids. While 9L and R/sub 3/ cell have different sensitivities to BCNU, they are equally sensitive to radiation. Mixed-cell spheroids consisting of 1% R/sub 3/ cells were treated with three doses of BCNU (10 μM) every 72 hr resulting in a shift in the 9L to R/sub 3/ ratio to greater than 50% R/sub 3/ cells. The combined protocols to be investigated will involve γ rays administered either 36 hr before or after each BCNU treatment. By initiating these combined protocols on spheroids of different sizes, the effectiveness of each protocol is evaluated with respect to the number of resistant cells present

  1. A cyclopalladated complex interacts with mitochondrial membrane thiol-groups and induces the apoptotic intrinsic pathway in murine and cisplatin-resistant human tumor cells

    International Nuclear Information System (INIS)

    Serrano, Fabiana A; Machado, Joel Jr; Santos, Edson L; Pesquero, João B; Martins, Rafael M; Travassos, Luiz R; Caires, Antonio CF; Rodrigues, Elaine G; Matsuo, Alisson L; Monteforte, Priscila T; Bechara, Alexandre; Smaili, Soraya S; Santana, Débora P; Rodrigues, Tiago; Pereira, Felipe V; Silva, Luis S

    2011-01-01

    Systemic therapy for cancer metastatic lesions is difficult and generally renders a poor clinical response. Structural analogs of cisplatin, the most widely used synthetic metal complexes, show toxic side-effects and tumor cell resistance. Recently, palladium complexes with increased stability are being investigated to circumvent these limitations, and a biphosphinic cyclopalladated complex {Pd 2 [S (-) C 2 , N-dmpa] 2 (μ-dppe)Cl 2 } named C7a efficiently controls the subcutaneous development of B16F10-Nex2 murine melanoma in syngeneic mice. Presently, we investigated the melanoma cell killing mechanism induced by C7a, and extended preclinical studies. B16F10-Nex2 cells were treated in vitro with C7a in the presence/absence of DTT, and several parameters related to apoptosis induction were evaluated. Preclinical studies were performed, and mice were endovenously inoculated with B16F10-Nex2 cells, intraperitoneally treated with C7a, and lung metastatic nodules were counted. The cytotoxic effects and the respiratory metabolism were also determined in human tumor cell lines treated in vitro with C7a. Cyclopalladated complex interacts with thiol groups on the mitochondrial membrane proteins, causes dissipation of the mitochondrial membrane potential, and induces Bax translocation from the cytosol to mitochondria, colocalizing with a mitochondrial tracker. C7a also induced an increase in cytosolic calcium concentration, mainly from intracellular compartments, and a significant decrease in the ATP levels. Activation of effector caspases, chromatin condensation and DNA degradation, suggested that C7a activates the apoptotic intrinsic pathway in murine melanoma cells. In the preclinical studies, the C7a complex protected against murine metastatic melanoma and induced death in several human tumor cell lineages in vitro, including cisplatin-resistant ones. The mitochondria-dependent cell death was also induced by C7a in human tumor cells. The cyclopalladated C7a complex is

  2. Tumor-reactive immune cells protect against metastatic tumor and induce immunoediting of indolent but not quiescent tumor cells.

    Science.gov (United States)

    Payne, Kyle K; Keim, Rebecca C; Graham, Laura; Idowu, Michael O; Wan, Wen; Wang, Xiang-Yang; Toor, Amir A; Bear, Harry D; Manjili, Masoud H

    2016-09-01

    Two major barriers to cancer immunotherapy include tumor-induced immune suppression mediated by myeloid-derived suppressor cells and poor immunogenicity of the tumor-expressing self-antigens. To overcome these barriers, we reprogrammed tumor-immune cell cross-talk by combined use of decitabine and adoptive immunotherapy, containing tumor-sensitized T cells and CD25(+) NKT cells. Decitabine functioned to induce the expression of highly immunogenic cancer testis antigens in the tumor, while also reducing the frequency of myeloid-derived suppressor cells and the presence of CD25(+) NKT cells rendered T cells, resistant to remaining myeloid-derived suppressor cells. This combinatorial therapy significantly prolonged survival of animals bearing metastatic tumor cells. Adoptive immunotherapy also induced tumor immunoediting, resulting in tumor escape and associated disease-related mortality. To identify a tumor target that is incapable of escape from the immune response, we used dormant tumor cells. We used Adriamycin chemotherapy or radiation therapy, which simultaneously induce tumor cell death and tumor dormancy. Resultant dormant cells became refractory to additional doses of Adriamycin or radiation therapy, but they remained sensitive to tumor-reactive immune cells. Importantly, we discovered that dormant tumor cells contained indolent cells that expressed low levels of Ki67 and quiescent cells that were Ki67 negative. Whereas the former were prone to tumor immunoediting and escape, the latter did not demonstrate immunoediting. Our results suggest that immunotherapy could be highly effective against quiescent dormant tumor cells. The challenge is to develop combinatorial therapies that could establish a quiescent type of tumor dormancy, which would be the best target for immunotherapy. © The Author(s).

  3. Tumors of germinal cells

    International Nuclear Information System (INIS)

    Plazas, Ricardo; Avila, Andres

    2002-01-01

    The tumors of germinal cells (TGC) are derived neoplasia of the primordial germinal cells that in the life embryonic migrant from the primitive central nervous system until being located in the gonads. Their cause is even unknown and they represent 95% of the testicular tumors. In them, the intention of the treatment is always healing and the diagnostic has improved thanks to the results of the handling multidisciplinary. The paper includes topics like their incidence and prevalence, epidemiology and pathology, clinic and diagnoses among other topics

  4. Sunitinib significantly suppresses the proliferation, migration, apoptosis resistance, tumor angiogenesis and growth of triple-negative breast cancers but increases breast cancer stem cells.

    Science.gov (United States)

    Chinchar, Edmund; Makey, Kristina L; Gibson, John; Chen, Fang; Cole, Shelby A; Megason, Gail C; Vijayakumar, Srinivassan; Miele, Lucio; Gu, Jian-Wei

    2014-01-01

    The majority of triple-negative breast cancers (TNBCs) are basal-like breast cancers. However there is no reported study on anti-tumor effects of sunitinib in xenografts of basal-like TNBC (MDA-MB-468) cells. In the present study, MDA-MB-231, MDA-MB-468, MCF-7 cells were cultured using RPMI 1640 media with 10% FBS. Vascular endothelia growth factor (VEGF) protein levels were detected using ELISA (R & D Systams). MDA-MB-468 cells were exposed to sunitinib for 18 hours for measuring proliferation (3H-thymidine incorporation), migration (BD Invasion Chamber), and apoptosis (ApopTag and ApoScreen Anuexin V Kit). The effect of sunitinib on Notch-1 expression was determined by Western blot in cultured MDA-MB-468 cells. 10(6) MDA-MB-468 cells were inoculated into the left fourth mammary gland fat pad in athymic nude-foxn1 mice. When the tumor volume reached 100 mm(3), sunitinib was given by gavage at 80 mg/kg/2 days for 4 weeks. Tumor angiogenesis was determined by CD31 immunohistochemistry. Breast cancer stem cells (CSCs) isolated from the tumors were determined by flow cytometry analysis using CD44(+)/CD24(-) or low. ELISA indicated that VEGF was much more highly expressed in MDA-MB-468 cells than MDA-MB-231 and MCF-7 cells. Sunitinib significantly inhibited the proliferation, invasion, and apoptosis resistance in cultured basal like breast cancer cells. Sunitinib significantly increased the expression of Notch-1 protein in cultured MDA-MB-468 or MDA-MB-231 cells. The xenograft models showed that oral sunitinib significantly reduced the tumor volume of TNBCs in association with the inhibition of tumor angiogeneisis, but increased breast CSCs. These findings support the hypothesis that the possibility should be considered of sunitinib increasing breast CSCs though it inhibits TNBC tumor angiogenesis and growth/progression, and that effects of sunitinib on Notch expression and hypoxia may increase breast cancer stem cells. This work provides the groundwork for an

  5. Inability of p53-reactivating compounds Nutlin-3 and RITA to overcome p53 resistance in tumor cells deficient in p53Ser46 phosphorylation.

    Science.gov (United States)

    Ma, Teng; Yamada, Shumpei; Ichwan, Solachuddin J A; Iseki, Sachiko; Ohtani, Kiyoshi; Otsu, Megumi; Ikeda, Masa-Aki

    2012-01-20

    The p53 tumor suppressor protein plays key roles in protecting cells from tumorigenesis. Phosphorylation of p53 at Ser46 (p53Ser46) is considered to be a crucial modification regulating p53-mediated apoptosis. Because the activity of p53 is impaired in most human cancers, restoration of wild-type p53 (wt-p53) function by its gene transfer or by p53-reactivating small molecules has been extensively investigated. The p53-reactivating compounds Nutlin-3 and RITA activate p53 in the absence of genotoxic stress by antagonizing the action of its negative regulator Mdm2. Although controversial, Nutlin-3 was shown to induce p53-mediated apoptosis in a manner independent of p53 phosphorylation. Recently, RITA was shown to induce apoptosis by promoting p53Ser46 phosphorylation. Here we examined whether Nutlin-3 or RITA can overcome resistance to p53-mediated apoptosis in p53-resistant tumor cell lines lacking the ability to phosphorylate p53Ser46. We show that Nutlin-3 did not rescue the apoptotic defect of a Ser46 phosphorylation-defective p53 mutant in p53-sensitive tumor cells, and that RITA neither restored p53Ser46 phosphorylation nor induced apoptosis in p53Ser46 phosphorylation-deficient cells retaining wt-p53. Furthermore, treatment with Nutlin-3 or RITA together with adenoviral p53 gene transfer also failed to induce apoptosis in p53Ser46 phosphorylation-deficient cells either expressing or lacking wt-p53. These results indicate that neither Nutlin-3 nor RITA in able to induce p53-mediated apoptosis in the absence of p53Ser46 phosphorylation. Thus, the dysregulation of this phosphorylation in tumor cells may be a critical factor that limits the efficacy of these p53-based cancer therapies. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Xenograft tumors derived from malignant pleural effusion of the patients with non-small-cell lung cancer as models to explore drug resistance.

    Science.gov (United States)

    Xu, Yunhua; Zhang, Feifei; Pan, Xiaoqing; Wang, Guan; Zhu, Lei; Zhang, Jie; Wen, Danyi; Lu, Shun

    2018-05-09

    Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations or anaplastic lymphoma kinase (ALK) fusions show dramatic responses to specific tyrosine kinase inhibitors (TKIs); however, after 10-12 months, secondary mutations arise that confer resistance. We generated a murine xenograft model using patient-derived NSCLC cells isolated from the pleural fluid of two patients with NSCLC to investigate the mechanisms of resistance against the ALK- and EGFR-targeted TKIs crizotinib and osimertinib, respectively. Genotypes of patient biopsies and xenograft tumors were determined by whole exome sequencing (WES), and patients and xenograft-bearing mice received targeted treatment (crizotinib or osimertinib) accordingly. Xenograft mice were also treated for prolonged periods to identify whether the development of drug resistance and/or treatment responses were associated with tumor size. Finally, the pathology of patients biopsies and xenograft tumors were compared histologically. The histological characteristics and chemotherapy responses of xenograft tumors were similar to the actual patients. WES showed that the genotypes of the xenograft and patient tumors were similar (an echinoderm microtubule-associated protein-like 4-ALK (EML4-ALK) gene fusion (patient/xenograft: CTC15035 EML4-ALK ) and EGFR L858R and T790M mutations (patient/xenograft: CTC15063 EGFR L858R, T790M )). After continuous crizotinib or osimertinib treatment, WES data suggested that acquired ALK E1210K mutation conferred crizotinib resistance in the CTC15035 EML4-ALK xenograft, while decreased frequencies of EGFR L858R and T790M mutations plus the appearance of v-RAF murine sarcoma viral oncogene homolog B (BRAF) G7V mutations and phosphatidylinositol-4-phosphate 3-kinase catalytic subunit type 2 alpha (PIK3C2A) A86fs frame shift mutations led to osimertinib resistance in the CTC15063 EGFR L858R, T790M xenografts. We successfully developed a new method of generating

  7. Circumvention of the multidrug-resistance protein (MRP-1) by an antitumor drug through specific inhibition of gene transcription in breast tumor cells.

    Science.gov (United States)

    Mansilla, Sylvia; Rojas, Marta; Bataller, Marc; Priebe, Waldemar; Portugal, José

    2007-04-01

    Multidrug-resistance protein 1 (MRP-1) confers resistance to a number of clinically important chemotherapeutic agents. The promoter of the mrp-1 gene contains an Sp1-binding site, which we targeted using the antitumor bis-anthracycline WP631. When MCF-7/VP breast cancer cells, which overexpress MRP-1 protein, were incubated with WP631 the expression of the multidrug-resistance protein gene decreased. Conversely, doxorubicin did not alter mrp-1 gene expression. The inhibition of gene expression was followed by a decrease in the activity of the MRP-1 protein. The IC(75) for WP631 (drug concentration required to inhibit cell growth by 75%) circumvented the drug-efflux pump, without addition of resistant modifiers. After treatment with WP631, MCF-7/VP cells were committed to die after entering mitosis (mitotic catastrophe), while treatment with doxorubicin did not affect cell growth. This is the first report on an antitumor drug molecule inhibiting the mrp-1 gene directly, rather than being simply a poor substrate for the transporter-mediated efflux. However, both situations appeared to coexist, thereby a superior cytotoxic effect was attained. Ours results suggest that WP631 offers great potential for the clinical treatment of tumors displaying a multidrug-resistance phenotype.

  8. Hsp90 inhibitor 17-AAG reduces ErbB2 levels and inhibits proliferation of the trastuzumab resistant breast tumor cell line JIMT-1.

    Science.gov (United States)

    Zsebik, Barbara; Citri, Ami; Isola, Jorma; Yarden, Yosef; Szöllosi, János; Vereb, György

    2006-04-15

    ErbB2, a member of the EGF receptor family of tyrosine kinases is overexpressed on many tumor cells of epithelial origin and is the molecular target of trastuzumab (Herceptin), the first humanized antibody used in the therapy of solid tumors. Trastuzumab, which is thought to act, at least in part, by downregulating ErbB2 expression is only effective in approximately 30-40% of ErbB2 positive breast tumors. Geldanamycin and its derivative 17-AAG are potential antitumor agents capable of downregulating client proteins of Hsp90, including ErbB2. To investigate the ability of 17-AAG to downregulate ErbB2 in trastuzumab resistant breast cancer cells and the possibility of 17-AAG and trastuzumab potentiating each other's effect, the recently established trastuzumab resistant breast cancer cell line, JIMT-1 was compared to the known trastuzumab sensitive SKBR-3 line. Baseline and stimulus-evoked dimerization and activation levels of ErbB2, and the effects of trastuzumab and 17-AAG alone and in combination on cell proliferation and apoptosis, as well as on ErbB2 expression and phosphorylation have been measured. Baseline activation and amenability to activation and downregulation by trastuzumab was much lower in the resistant line. However, 17-AAG enhanced ErbB2 homodimerization after 5-10 min of treatment in both cell lines, and decreased proliferation with an IC50 of 70 nM for SKBR-3 and 10nM for JIMT-1. Thus, 17-AAG may be a useful drug in trastuzumab resistant ErbB2 overexpressing tumors. The antiproliferative effect of 17-AAG was positively correlated with phosphorylation and downregulation of ErbB2 and was dominated by apoptosis, although, especially at higher doses, necrosis was also present. Interestingly, IC50 values for ErbB2 downregulation and phosphorylation, in the 30-40 nM range, were not significantly different for the two cell lines. This observation and the negative correlation between resting ErbB2 levels and the antiproliferative effect of 17-AAG may

  9. Androgen receptor expression in Circulating Tumor Cells from castration-resistant prostate cancer patients with novel endocrine agents

    NARCIS (Netherlands)

    Crespo, M.; van Dalum, Guus; Ferraldeschi, R.; Zafeiriou, Z.; Sideris, S.; Lorente, D.; Bianchini, D.; Rodrigues, D.N.; Rijsnaes, R.; Miranda, S.; Figueiredo, I.; Flohr, P.; Nowakowska, K.; de Bono, J.S.; Terstappen, Leonardus Wendelinus Mathias Marie; Attard, G.

    2015-01-01

    Background: Abiraterone and enzalutamide are novel endocrine treatments that abrogate androgen receptor (AR) signalling in castration-resistant prostate cancer (CRPC). Here, we developed a circulating tumour cells (CTCs)-based assay to evaluate AR expression in real-time in CRPC and investigated

  10. Retrotransposon Targeting of Tumor Cells

    National Research Council Canada - National Science Library

    Wu, Dongdong; DeVaux, George

    2005-01-01

    .... Cancer gene therapy techniques include oncogene inactivation, tumor suppressor gene replacement, inhibition of angiogenesis, immunopotentiation, molecular chemotherapy, and transfer of drug resistance genes...

  11. A perillyl alcohol-conjugated analog of 3-bromopyruvate without cellular uptake dependency on monocarboxylate transporter 1 and with activity in 3-BP-resistant tumor cells.

    Science.gov (United States)

    Chen, Thomas C; Yu, Jiali; Nouri Nigjeh, Eslam; Wang, Weijun; Myint, Phyo Thazin; Zandi, Ebrahim; Hofman, Florence M; Schönthal, Axel H

    2017-08-01

    The anticancer agent 3-bromopyruvate (3-BP) is viewed as a glycolytic inhibitor that preferentially kills glycolytic cancer cells through energy depletion. However, its cytotoxic activity is dependent on cellular drug import through transmembrane monocarboxylate transporter 1 (MCT-1), which restricts its anticancer potential to MCT-1-positive tumor cells. We created and characterized an MCT-1-independent analog of 3-BP, called NEO218. NEO218 was synthesized by covalently conjugating 3-BP to perillyl alcohol (POH), a natural monoterpene. The responses of various tumor cell lines to treatment with either compound were characterized in the presence or absence of supplemental pyruvate or antioxidants N-acetyl-cysteine (NAC) and glutathione (GSH). Drug effects on glyceraldehyde 3-phosphate dehydrogenase (GAPDH) enzyme activity were investigated by mass spectrometric analysis. The development of 3-BP resistance was investigated in MCT-1-positive HCT116 colon carcinoma cells in vitro. Our results show that NEO218: (i) pyruvylated GAPDH on all 4 of its cysteine residues and shut down enzymatic activity; (ii) severely lowered cellular ATP content below life-sustaining levels, and (iii) triggered rapid necrosis. Intriguingly, supplemental antioxidants effectively prevented cytotoxic activity of NEO218 as well as 3-BP, but supplemental pyruvate powerfully protected cells only from 3-BP, not from NEO218. Unlike 3-BP, NEO218 exerted its potent cytotoxic activity irrespective of cellular MCT-1 status. Treatment of HCT116 cells with 3-BP resulted in prompt development of resistance, based on the emergence of MCT-1-negative cells. This was not the case with NEO218, and highly 3-BP-resistant cells remained exquisitely sensitive to NEO218. Thus, our study identifies a mechanism by which tumor cells develop rapid resistance to 3-BP, and presents NEO218 as a superior agent not subject to this cellular defense. Furthermore, our results offer alternative interpretations of previously

  12. Metastatic castration-resistant prostate cancer: a current view on drug therapy and alternative tumor cell regulation

    Directory of Open Access Journals (Sweden)

    R. A. Gafanov

    2018-01-01

    Full Text Available Prostate cancer (PC is one of the most common causes of death from malignant neoplasms in men in many countries around the world. Transmission of the signal in the androgenic axis of regulation is crucial for the development and progression of PC. Despite the constant dependence on androgen receptor signals in castration resistance, the use of new anti-androgenic drugs invariably leads to the stability  of the ongoing treatment. The interaction of androgen receptor and alternative (phosphoinositide-3-kinases, PI3K pathways in the regulation of cells can be one of the mechanisms of resistance to treatment. In this article, we describe current treatments for metastatic castration-resistant PC and the possible role of the PI3K pathway in the pathogenesis and progression of PC.

  13. Hypoxic resistance of KRAS mutant tumor cells to 3-Bromopyruvate is counteracted by Prima-1 and reversed by N-acetylcysteine.

    Science.gov (United States)

    Orue, Andrea; Chavez, Valery; Strasberg-Rieber, Mary; Rieber, Manuel

    2016-11-18

    The metabolic inhibitor 3-bromopyruvate (3-BrPA) is a promising anti-cancer alkylating agent, shown to inhibit growth of some colorectal carcinoma with KRAS mutation. Recently, we demonstrated increased resistance to 3-BrPA in wt p53 tumor cells compared to those with p53 silencing or mutation. Since hypoxic microenvironments select for tumor cells with diminished therapeutic response, we investigated whether hypoxia unequally increases resistance to 3-BrPA in wt p53 MelJuso melanoma harbouring (Q61L)-mutant NRAS and wt BRAF, C8161 melanoma with (G12D)-mutant KRAS (G464E)-mutant BRAF, and A549 lung carcinoma with a KRAS (G12S)-mutation. Since hypoxia increases the toxicity of the p53 activator, Prima-1 against breast cancer cells irrespective of their p53 status, we also investigated whether Prima-1 reversed hypoxic resistance to 3-BrPA. In contrast to the high susceptibility of hypoxic mutant NRAS MelJuso cells to 3-BrPA or Prima-1, KRAS mutant C8161 and A549 cells revealed hypoxic resistance to 3-BrPA counteracted by Prima-1. In A549 cells, Prima-1 increased p21CDKN1mRNA, and reciprocally inhibited mRNA expression of the SLC2A1-GLUT1 glucose transporter-1 and ALDH1A1, gene linked to detoxification and stem cell properties. 3-BrPA lowered CAIX and VEGF mRNA expression. Death from joint Prima-1 and 3-BrPA treatment in KRAS mutant A549 and C8161 cells seemed mediated by potentiating oxidative stress, since it was antagonized by the anti-oxidant and glutathione precursor N-acetylcysteine. This report is the first to show that Prima-1 kills hypoxic wt p53 KRAS-mutant cells resistant to 3-BrPA, partly by decreasing GLUT-1 expression and exacerbating pro-oxidant stress.

  14. Rapid emergence and mechanisms of resistance by U87 glioblastoma cells to doxorubicin in an in vitro tumor microfluidic ecology

    Science.gov (United States)

    Austin, Robert; Lee, Sanghyuk; Park, Sungsu

    We have developed a microfluidic device consisting of approximately 500 hexagonal micro-compartments which provides a complex ecology with wide ranges of drug and nutrient gradients and local populations. This ecology of a fragmented metapopulation induced the drug resistance in stage IV U87 glioblastoma cells to doxorubicin in seven days. Exome and transcriptome sequencing of the resistant cells identified mutations and differentially expressed genes. Gene ontology and pathway analyses of the genes identified showed that they were functionally relevant with the established mechanisms of doxorubicin action. Functional experiments support the in silico analyses and together demonstrate the effects of these genetic changes. Our findings suggest that given the rapid evolution of resistance and the focused response, this technology could act as a rapid screening modality for genetic aberrations leading to resistance to chemotherapy as well as counter-selection of drugs unlikely to be successful ultimately. Technology Innovation Program of the Ministry of Trade, Industry and Energy, Republic of Korea (10050154 to S.L. and S.P.), the National Research Foundation of Korea (NRF-2014M3C9A3065221 to S.L., NRF-2015K1A4A3047851 to J.K. and S.L.) funded by the Minis.

  15. Pericytes limit tumor cell metastasis

    DEFF Research Database (Denmark)

    Xian, Xiaojie; Håkansson, Joakim; Ståhlberg, Anders

    2006-01-01

    Previously we observed that neural cell adhesion molecule (NCAM) deficiency in beta tumor cells facilitates metastasis into distant organs and local lymph nodes. Here, we show that NCAM-deficient beta cell tumors grew leaky blood vessels with perturbed pericyte-endothelial cell-cell interactions...... the microvessel wall. To directly address whether pericyte dysfunction increases the metastatic potential of solid tumors, we studied beta cell tumorigenesis in primary pericyte-deficient Pdgfb(ret/ret) mice. This resulted in beta tumor cell metastases in distant organs and local lymph nodes, demonstrating a role...... and deficient perivascular deposition of ECM components. Conversely, tumor cell expression of NCAM in a fibrosarcoma model (T241) improved pericyte recruitment and increased perivascular deposition of ECM molecules. Together, these findings suggest that NCAM may limit tumor cell metastasis by stabilizing...

  16. ENO1 promotes tumor proliferation and cell adhesion mediated drug resistance (CAM-DR) in Non-Hodgkin's Lymphomas

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xinghua; Miao, Xiaobing; Wu, Yaxun; Li, Chunsun; Guo, Yan; Liu, Yushan; Chen, Yali; Lu, Xiaoyun [Department of Pathology, Affiliated Cancer Hospital of Nantong University, 30 North Tongyang Road, Pingchao, Nantong 226361, Jiangsu (China); Wang, Yuchan, E-mail: wangyuchannt@126.com [Department of Pathogen and Immunology, Medical College, Nantong University, 19 Qixiu Road, Nantong 226001, Jiangsu (China); He, Song, E-mail: hesongnt@126.com [Department of Pathology, Affiliated Cancer Hospital of Nantong University, 30 North Tongyang Road, Pingchao, Nantong 226361, Jiangsu (China)

    2015-07-15

    Enolases are glycolytic enzymes responsible for the ATP-generated conversion of 2-phosphoglycerate to phosphoenolpyruvate. In addition to the glycolytic function, Enolase 1 (ENO1) has been reported up-regulation in several tumor tissues. In this study, we investigated the expression and biologic function of ENO1 in Non-Hodgkin's Lymphomas (NHLs). Clinically, by western blot analysis we observed that ENO1 expression was apparently higher in diffuse large B-cell lymphoma than in the reactive lymphoid tissues. Subsequently, immunohistochemical staining of 144 NHLs suggested that the expression of ENO1 was significantly lower in the indolent lymphomas compared with the progressive lymphomas. Further, we identified ENO1 as an independent prognostic factor, and it was significantly correlated with overall survival of NHL patients. In addition, we found that ENO1 could promote cell proliferation, regulate cell cycle associated gene and PI3K/AKT signaling pathway in NHLs. Finally, we verified that ENO1 participated in the process of lymphoma cell adhesion mediated drug resistance (CAM-DR). Adhesion to FN or HS5 cells significantly protected OCI-Ly8 and Daudi cells from cytotoxicity compared with those cultured in suspension, and these effects were attenuated when transfected with ENO1-siRNA. Based on the study, we propose that inhibition of ENO1 expression may be a novel strategy for therapy for NHLs patients, and it may be a target for drug resistance. - Highlights: • ENO1 expression is reversely correlated with clinical outcomes of patients with NHLs. • ENO1 promotes the proliferation of NHL cells. • ENO1 regulates cell adhesion mediated drug resistance.

  17. Tyrosine isomers mediate the classical phenomenon of concomitant tumor resistance.

    Science.gov (United States)

    Ruggiero, Raúl A; Bruzzo, Juan; Chiarella, Paula; di Gianni, Pedro; Isturiz, Martín A; Linskens, Susana; Speziale, Norma; Meiss, Roberto P; Bustuoabad, Oscar D; Pasqualini, Christiane D

    2011-11-15

    Concomitant tumor resistance (CR) is a phenomenon originally described in 1906 in which a tumor-bearing host is resistant to the growth of secondary tumor implants and metastasis. Although recent studies have indicated that T-cell-dependent processes mediate CR in hosts bearing immunogenic small tumors, manifestations of CR induced by immunogenic and nonimmunogenic large tumors have been associated with an elusive serum factor. In this study, we identify this serum factor as tyrosine in its meta and ortho isoforms. In three different murine models of cancer that generate CR, both meta-tyrosine and ortho-tyrosine inhibited tumor growth. In addition, we showed that both isoforms of tyrosine blocked metastasis in a fourth model that does not generate CR but is sensitive to CR induced by other tumors. Mechanistic studies showed that the antitumor effects of the tyrosine isoforms were mediated, in part, by early inhibition of mitogen-activated protein/extracellular signal-regulated kinase pathway and inactivation of STAT3, potentially driving tumor cells into a state of dormancy. By revealing a molecular basis for the classical phenomenon of CR, our findings may stimulate new generalized approaches to limit the development of metastases that arise after resection of primary tumors, an issue of pivotal importance to oncologists and their patients. ©2011 AACR

  18. A decrease in ubiquitination and resulting prolonged life-span of KIT underlies the KIT overexpression-mediated imatinib resistance of KIT mutation-driven canine mast cell tumor cells.

    Science.gov (United States)

    Kobayashi, Masato; Kuroki, Shiori; Kurita, Sena; Miyamoto, Ryo; Tani, Hiroyuki; Tamura, Kyoichi; Bonkobara, Makoto

    2017-10-01

    Overexpression of KIT is one of the mechanisms that contributes to imatinib resistance in KIT mutation-driven tumors. Here, the mechanism underlying this overexpression of KIT was investigated using an imatinib-sensitive canine mast cell tumor (MCT) line CoMS, which has an activating mutation in KIT exon 11. A KIT-overexpressing imatinib-resistant subline, rCoMS1, was generated from CoMS cells by their continuous exposure to increasing concentrations of imatinib. Neither a secondary mutation nor upregulated transcription of KIT was detected in rCoMS1 cells. A decrease in KIT ubiquitination, a prolonged KIT life-span, and KIT overexpression were found in rCoMS1 cells. These events were suppressed by withdrawal of imatinib and were re-induced by re‑treatment with imatinib. These findings suggest that imatinib elicited overexpression of KIT via suppression of its ubiquitination. These results also indicated that imatinib-induced overexpression of KIT in rCoMS1 cells was not a permanently acquired feature but was a reversible response of the cells. Moreover, the pan deubiquitinating enzyme inhibitor PR619 prevented imatinib induction of KIT overexpression, suggesting that the imatinib-induced decrease in KIT ubiquitination could be mediated by upregulation and/or activation of deubiquitinating enzyme(s). It may be possible that a similar mechanism of KIT overexpression underlies the acquisition of imatinib resistance in some human tumors that are driven by KIT mutation.

  19. Interferon-gamma and tumor necrosis factor-alpha sensitize primarily resistant human endometrial stromal cells to Fas-mediated apoptosis

    DEFF Research Database (Denmark)

    Fluhr, Herbert; Krenzer, Stefanie; Stein, Gerburg M

    2007-01-01

    The subtle interaction between the implanting embryo and the maternal endometrium plays a pivotal role during the process of implantation. Human endometrial stromal cells (ESCs) express Fas and the implanting trophoblast cells secrete Fas ligand (FASLG, FasL), suggesting a possible role for Fas......-mediated signaling during early implantation. Here we show that ESCs are primarily resistant to Fas-mediated apoptosis independently of their state of hormonal differentiation. Pre-treatment of ESCs with interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha sensitizes them to become apoptotic upon stimulation...... of Fas by an agonistic anti-Fas antibody. Incubation of ESCs with the early embryonic signal human chorionic gonadotropin (hCG, CGB) does not influence their reaction to Fas stimulation. The sensitizing effect of IFN-gamma and TNF-alpha was accompanied by a significant upregulation of Fas and FLICE...

  20. INPP4B-mediated tumor resistance is associated with modulation of glucose metabolism via hexokinase 2 regulation in laryngeal cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Min, Joong Won [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Kwang Il [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Hyun-Ah; Kim, Eun-Kyu; Noh, Woo Chul [Department of Surgery, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Jeon, Hong Bae [Biomedical Research Institute, MEDIPOST Co., Ltd., Seoul (Korea, Republic of); Cho, Dong-Hyung [Graduate School of East-West Medical Science, Kyung Hee University, Gyeonggi-do (Korea, Republic of); Oh, Jeong Su [Department of Genetic Engineering, Sungkyunkwan University, Suwon (Korea, Republic of); Park, In-Chul; Hwang, Sang-Gu [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Jae-Sung, E-mail: jaesung@kirams.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2013-10-11

    Highlights: •HIF-1α-regulated INPP4B enhances glycolysis. •INPP4B regulates aerobic glycolysis by inducing HK2 via Akt-mTOR pathway. •Blockage of INPP4B and HK2 sensitizes radioresistant laryngeal cancer cells to radiation and anticancer drug. •INPP4B is associated with HK2 in human laryngeal cancer tissues. -- Abstract: Inositol polyphosphate 4-phosphatase type II (INPP4B) was recently identified as a tumor resistance factor in laryngeal cancer cells. Herein, we show that INPP4B-mediated resistance is associated with increased glycolytic phenotype. INPP4B expression was induced by hypoxia and irradiation. Intriguingly, overexpression of INPP4B enhanced aerobic glycolysis. Of the glycolysis-regulatory genes, hexokinase 2 (HK2) was mainly regulated by INPP4B and this regulation was mediated through the Akt-mTOR pathway. Notably, codepletion of INPP4B and HK2 markedly sensitized radioresistant laryngeal cancer cells to irradiation or anticancer drug. Moreover, INPP4B was significantly associated with HK2 in human laryngeal cancer tissues. Therefore, these results suggest that INPP4B modulates aerobic glycolysis via HK2 regulation in radioresistant laryngeal cancer cells.

  1. Mechanisms of Intrinsic Tumor Resistance to Immunotherapy

    Directory of Open Access Journals (Sweden)

    John Rieth

    2018-05-01

    Full Text Available An increased understanding of the interactions between the immune system and tumors has opened the door to immunotherapy for cancer patients. Despite some success with checkpoint inhibitors including ipilimumab, pembrolizumab, and nivolumab, most cancer patients remain unresponsive to such immunotherapy, likely due to intrinsic tumor resistance. The mechanisms most likely involve reducing the quantity and/or quality of antitumor lymphocytes, which ultimately are driven by any number of developments: tumor mutations and adaptations, reduced neoantigen generation or expression, indoleamine 2,3-dioxygenase (IDO overexpression, loss of phosphatase and tensin homologue (PTEN expression, and overexpression of the Wnt–β-catenin pathway. Current work in immunotherapy continues to identify various tumor resistance mechanisms; future work is needed to develop adjuvant treatments that target those mechanisms, in order to improve the efficacy of immunotherapy and to expand its scope.

  2. Cancer stem cells and chemoradiation resistance

    International Nuclear Information System (INIS)

    Ishii, Hideshi; Mori, Masaki; Iwatsuki, Masaaki; Ieta, Keisuke; Ohta, Daisuke; Haraguchi, Naotsugu; Mimori, Koshi

    2008-01-01

    Cancer is a disease of genetic and epigenetic alterations, which are emphasized as the central mechanisms of tumor progression in the multistepwise model. Discovery of rare subpopulations of cancer stem cells (CSCs) has created a new focus in cancer research. The heterogeneity of tumors can be explained with the help of CSCs supported by antiapoptotic signaling. CSCs mimic normal adult stem cells by demonstrating resistance to toxic injuries and chemoradiation therapy. Moreover, they might be responsible for tumor relapse following apparent beneficial treatments. Compared with hematopoietic malignancies, conventional therapy regimes in solid tumors have improved the overall survival marginally, illustrating the profound impact of treatment resistance. This implies that the present therapies, which follow total elimination of rapidly dividing and differentiated tumor cells, need to be modified to target CSCs that repopulate the tumor. In this review article, we report on recent findings regarding the involvement of CSCs in chemoradiation resistance and provide new insights into their therapeutic implications in cancer. (author)

  3. Scopadulciol, Isolated from Scoparia dulcis, Induces β-Catenin Degradation and Overcomes Tumor Necrosis Factor-Related Apoptosis Ligand Resistance in AGS Human Gastric Adenocarcinoma Cells.

    Science.gov (United States)

    Fuentes, Rolly G; Toume, Kazufumi; Arai, Midori A; Sadhu, Samir K; Ahmed, Firoj; Ishibashi, Masami

    2015-04-24

    Scopadulciol (1), a scopadulan-type diterpenoid, was isolated from Scoparia dulcis along with three other compounds (2-4) by an activity-guided approach using the TCF reporter (TOP) luciferase-based assay system. A fluorometric microculture cytotoxicity assay (FMCA) revealed that compound 1 was cytotoxic to AGS human gastric adenocarcinoma cells. The treatment of AGS cells with 1 decreased β-catenin levels and also inhibited its nuclear localization. The pretreatment of AGS cells with a proteasome inhibitor, either MG132 or epoxomicin, protected against the degradation of β-catenin induced by 1. The 1-induced degradation of β-catenin was also abrogated in the presence of pifithrin-α, an inhibitor of p53 transcriptional activity. Compound 1 inhibited TOP activity in AGS cells and downregulated the protein levels of cyclin D1, c-myc, and survivin. Compound 1 also sensitized AGS cells to tumor necrosis factor-related apoptosis ligand (TRAIL)-induced apoptosis by increasing the levels of the death receptors, DR4 and DR5, and decreasing the level of the antiapoptotic protein Bcl-2. Collectively, our results demonstrated that 1 induced the p53- and proteasome-dependent degradation of β-catenin, which resulted in the inhibition of TCF/β-catenin transcription in AGS cells. Furthermore, 1 enhanced apoptosis in TRAIL-resistant AGS when combined with TRAIL.

  4. Vindesine in plasma cell tumors.

    Science.gov (United States)

    Salvagno, L; Paccagnella, A; Chiarion Sileni, V; De Besi, P; Frizzarin, M; Casara, D; Fiorentino, M V

    1985-12-31

    Twenty-one patients with plasma cell tumors received vindesine (VDS) at the dose of 3 mg/m2 i.v. on day 1 plus prednisone at the dose of 100 mg p.o. from day 1 to 5, recycling every 8 days 3 times and then every 10-12 days. In 3 patients with gastric or duodenal ulcer prednisone was not administered. All but one patient were heavily pretreated and resistant to M-2 regimen. Overall there were 4 objective responses (19%): 2 among 15 patients (13%) with multiple myeloma and 2 among 6 patients (33%) with extramedullary plasmacytoma (EMP). The responses lasted for 2, 12, 15 and 48+ months. One previously untreated EMP patient received VDS without prednisone and obtained a complete long-lasting remission. The association of VDS with high-dose prednisone seems to have some activity in plasma cell tumors; probably in multiple myeloma the objective responses are due to the high dose of cortisone rather than to VDS. On the contrary, in EMP patients, VDS may be an active agent, even if administered without cortisone.

  5. Rocaglamide overcomes tumor necrosis factor-related apoptosis-inducing ligand resistance in hepatocellular carcinoma cells by attenuating the inhibition of caspase-8 through cellular FLICE-like-inhibitory protein downregulation.

    Science.gov (United States)

    Luan, Zhou; He, Ying; He, Fan; Chen, Zhishui

    2015-01-01

    The enhancement of apoptosis is a therapeutic strategy used in the treatment of cancer. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising antitumor agent. However, hepatocellular carcinoma (HCC) cells exhibit marked resistance to the induction of cell death by TRAIL. The present study investigated whether rocaglamide, a naturally occurring product isolated from the genus Aglaia, is able to sensitize resistant HCC cells to TRAIL-mediated apoptosis. Two HCC cell lines, HepG2 and Huh-7, were treated with rocaglamide and/or TRAIL and the induction of apoptosis and effects on the TRAIL signaling pathway were investigated. The in vivo efficacy of rocaglamide was determined in TRAIL-resistant Huh-7-derived tumor xenografts. Rocaglamide significantly sensitized the TRAIL-resistant HCC cells to apoptosis by TRAIL, which resulted from the rocaglamide-mediated downregulation of cellular FLICE-like inhibitory protein and subsequent caspase-8 activation. Furthermore, rocaglamide markedly inhibited tumor growth from Huh-7 cells propagated in severe combined immunodeficient mice, suggesting that chemosentization also occurred in vivo. These data suggest that rocaglamide acted synergistically with TRAIL against the TRAIL-resistant HCC cells. Thus, it is concluded that rocaglamide as an adjuvant to TRAIL-based therapy may present a promising therapeutic approach for the treatment of HCC.

  6. Targeting Therapy Resistant Tumor Vessels

    Science.gov (United States)

    2008-08-01

    Morris LS. Hysterectomy vs. resectoscopic endometrial ablation for the control of abnormal uterine bleeding . A cost-comparative study. J Reprod Med 1994;39...after the antibody treatment contain a pericyte coat, vessel architecture is normal, the diameter of the vessels is smaller (dilated, abnormal vessels...involvement of proteases from inflammatory mast cells and functionally abnormal (Carmeliet and Jain, 2000; Pasqualini (Coussens et al., 1999) and other bone

  7. Molecular biology of testicular germ cell tumors.

    Science.gov (United States)

    Gonzalez-Exposito, R; Merino, M; Aguayo, C

    2016-06-01

    Testicular germ cell tumors (TGCTs) are the most common solid tumors in young adult men. They constitute a unique pathology because of their embryonic and germ origin and their special behavior. Genetic predisposition, environmental factors involved in their development and genetic aberrations have been under study in many works throughout the last years trying to explain the susceptibility and the transformation mechanism of TGCTs. Despite the high rate of cure in this type of tumors because its particular sensitivity to cisplatin, there are tumors resistant to chemotherapy for which it is needed to find new therapies. In the present work, it has been carried out a literature review on the most important molecular aspects involved in the onset and development of such tumors, as well as a review of the major developments regarding prognostic factors, new prognostic biomarkers and the possibility of new targeted therapies.

  8. Innate Lymphoid Cells in Tumor Immunity.

    Science.gov (United States)

    van Beek, Jasper J P; Martens, Anne W J; Bakdash, Ghaith; de Vries, I Jolanda M

    2016-02-25

    Innate lymphoid cells (ILCs) are a group of immune cells of the lymphoid lineage that do not possess antigen specificity. The group includes natural killer (NK) cells, lymphoid tissue inducer (LTi) cells and the recently identified ILC1s, ILC2s and ILC3s. Although the role of NK cells in the context of cancer has been well established, the involvement of other ILC subsets in cancer progression and resistance is just emerging. Here, we review the literature on the role of the different ILC subsets in tumor immunity and discuss its implications for cancer treatment and monitoring.

  9. Radiogenetic therapy: strategies to overcome tumor resistance.

    Science.gov (United States)

    Marples, B; Greco, O; Joiner, M C; Scott, S D

    2003-01-01

    The aim of cancer gene therapy is to selectively kill malignant cells at the tumor site, by exploiting traits specific to cancer cells and/or solid tumors. Strategies that take advantage of biological features common to different tumor types are particularly promising, since they have wide clinical applicability. Much attention has focused on genetic methods that complement radiotherapy, the principal treatment modality, or that exploit hypoxia, the most ubiquitous characteristic of most solid cancers. The goal of this review is to highlight two promising gene therapy methods developed specifically to target the tumor volume that can be readily used in combination with radiotherapy. The first approach uses radiation-responsive gene promoters to control the selective expression of a suicide gene (e.g., herpes simplex virus thymidine kinase) to irradiated tissue only, leading to targeted cell killing in the presence of a prodrug (e.g., ganciclovir). The second method utilizes oxygen-dependent promoters to produce selective therapeutic gene expression and prodrug activation in hypoxic cells, which are refractive to conventional radiotherapy. Further refining of tumor targeting can be achieved by combining radiation and hypoxia responsive elements in chimeric promoters activated by either and dual stimuli. The in vitro and in vivo studies described in this review suggest that the combination of gene therapy and radiotherapy protocols has potential for use in cancer care, particularly in cases currently refractory to treatment as a result of inherent or hypoxia-mediated radioresistance.

  10. Inhibition of phosphatidylinositol 3-kinase promotes tumor cell resistance to chemotherapeutic agents via a mechanism involving delay in cell cycle progression

    International Nuclear Information System (INIS)

    McDonald, Gail T.; Sullivan, Richard; Pare, Genevieve C.; Graham, Charles H.

    2010-01-01

    Approaches to overcome chemoresistance in cancer cells have involved targeting specific signaling pathways such as the phosphatidylinositol 3-kinase (PI3K) pathway, a stress response pathway known to be involved in the regulation of cell survival, apoptosis and growth. The present study determined the effect of PI3K inhibition on the clonogenic survival of human cancer cells following exposure to various chemotherapeutic agents. Treatment with the PI3K inhibitors LY294002 or Compound 15e resulted in increased survival of MDA-MB-231 breast carcinoma cells after exposure to doxorubicin, etoposide, 5-fluorouracil, and vincristine. Increased survival following PI3K inhibition was also observed in DU-145 prostate, HCT-116 colon and A-549 lung carcinoma cell lines exposed to doxorubicin. Increased cell survival mediated by LY294002 was correlated with a decrease in cell proliferation, which was linked to an increase in the proportion of cells in the G 1 phase of the cell cycle. Inhibition of PI3K signaling also resulted in higher levels of the cyclin-dependent kinase inhibitors p21 Waf1/Cip1 and p27 Kip1 ; and knockdown of p27 kip1 with siRNA attenuated resistance to doxorubicin in cells treated with LY294002. Incubation in the presence of LY294002 after exposure to doxorubicin resulted in decreased cell survival. These findings provide evidence that PI3K inhibition leads to chemoresistance in human cancer cells by causing a delay in cell cycle; however, the timing of PI3K inhibition (either before or after exposure to anti-cancer agents) may be a critical determinant of chemosensitivity.

  11. Sertoli-Leydig cell tumor

    Science.gov (United States)

    Sertoli-Leydig cell tumor (SLCT) is a rare cancer of the ovaries. The cancer cells produce and release a male sex hormone ... lead to cancer. SLCT starts in the female ovaries. The cancer cells release a male sex hormone. As a ...

  12. Differential thermo-resistance of multicellular tumor spheroids

    International Nuclear Information System (INIS)

    Khoei, S.; Goliaei, B.; Neshasteh-Rize, A.

    2004-01-01

    Many cell lines, when cultured under proper conditions, can form three dimensional structures called multicellular spheroids. These spheroids resemble in vivo tumor models in several aspects. Therefore, studying growth characteristics and behavior of spheroids is beneficial in understanding the behavior of tumors under various experimental conditions. In this work, we have studied the growth properties, along with the thermal characteristics of spheroids of Du 145 human prostate carcinoma cell lines and compared the results to monolayer cultures of these cells. For this purpose, The Du 145 cells were cultured either as monolayer or spheroids. At various times after initiation of cultures, the growth properties of spheroids as a function of seeding cell number was determined. To evaluate the thermal characteristics of spheroids, they were heated at various stages of growth at 43 d ig c for various periods. The thermal response was judged by the survival fraction of colony forming cells in spheroids or monolayer culture following heat treatment. The results showed spheroids were more resistant to heat than monolayer cultures at all stages of development. However, the extent of this thermal resistant was dependent on the age, and consequently, the size of the spheroid. The result suggests that the differential thermal resistance of the spheroid cultures develop gradually during the growth of spheroid cultures of Du 145 cell line

  13. Deregulation of apoptotic volume decrease and ionic movements in multidrug-resistant tumor cells: role of chloride channels

    DEFF Research Database (Denmark)

    Poulsen, Kristian Arild; Andersen, E C; Hansen, C F

    2010-01-01

    was further reduced. AVD(1) and AVD(2) were coupled to net loss of Cl(-), K(+), Na(+), and amino acids (ninhydrin-positive substances), whereas during AVD(T), Na(+) and Cl(-) were accumulated. MDR EATC was resistant to cisplatin, showing increased viability and less caspase 3 activation. Compared with WT EATC...

  14. Synthetic Nanoparticles That Promote Tumor Necrosis Factor Receptor 2 Expressing Regulatory T Cells in the Lung and Resistance to Allergic Airways Inflammation

    Directory of Open Access Journals (Sweden)

    Rohimah Mohamud

    2017-12-01

    Full Text Available Synthetic glycine coated 50 nm polystyrene nanoparticles (NP (PS50G, unlike ambient NP, do not promote pulmonary inflammation, but instead, render lungs resistant to the development of allergic airway inflammation. In this study, we show that PS50G modulate the frequency and phenotype of regulatory T cells (Treg in the lung, specifically increasing the proportion of tumor necrosis factor 2 (TNFR2 expressing Treg. Mice pre-exposed to PS50G, which were sensitized and then challenged with an allergen a month later, preferentially expanded TNFR2+Foxp3+ Treg, which further expressed enhanced levels of latency associated peptide and cytotoxic T-lymphocyte associated molecule-4. Moreover, PS50G-induced CD103+ dendritic cell activation in the lung was associated with the proliferative expansion of TNFR2+Foxp3+ Treg. These findings provide the first evidence that engineered NP can promote the selective expansion of maximally suppressing TNFR2+Foxp3+ Treg and further suggest a novel mechanism by which NP may promote healthy lung homeostasis.

  15. Overcoming tumor resistance by heterologous adeno-poxvirus combination therapy

    Directory of Open Access Journals (Sweden)

    Markus Vähä-Koskela

    2014-01-01

    Full Text Available Successful cancer control relies on overcoming resistance to cell death and on activation of host antitumor immunity. Oncolytic viruses are particularly attractive in this regard, as they lyse infected tumor cells and trigger robust immune responses during the infection. However, repeated injections of the same virus promote antiviral rather than antitumor immunity and tumors may mount innate antiviral defenses to restrict oncolytic virus replication. In this article, we have explored if alternating the therapy virus could circumvent these problems. We demonstrate in two virus-resistant animal models a substantial delay in antiviral immune- and innate cellular response induction by alternating injections of two immunologically distinct oncolytic viruses, adenovirus, and vaccinia virus. Our results are in support of clinical development of heterologous adeno-/vaccinia virus therapy of cancer.

  16. Approaches to drug resistance in solid tumors : with emphasis on lung cancer

    NARCIS (Netherlands)

    Bakker, Marleen

    2005-01-01

    De novo or acquired resistance of tumor cells to anticancer agents remains a major problem for the therapeutic efficacy of chemotherapeutic drugs. Most solid tumors are intrinsically insensitive or acquire resistance after initial response to chemotherapy. Different mechanisms seem to play a role in

  17. Tumor cell culture on collagen–chitosan scaffolds as three-dimensional tumor model: A suitable model for tumor studies

    Directory of Open Access Journals (Sweden)

    Aziz Mahmoudzadeh

    2016-07-01

    Full Text Available Tumor cells naturally live in three-dimensional (3D microenvironments, while common laboratory tests and evaluations are done in two-dimensional (2D plates. This study examined the impact of cultured 4T1 cancer cells in a 3D collagen–chitosan scaffold compared with 2D plate cultures. Collagen–chitosan scaffolds were provided and passed confirmatory tests. 4T1 tumor cells were cultured on scaffolds and then tumor cells growth rate, resistance to X-ray radiation, and cyclophosphamide as a chemotherapy drug were analyzed. Furthermore, 4T1 cells were extracted from the scaffold model and were injected into the mice. Tumor growth rate, survival rate, and systemic immune responses were evaluated. Our results showed that 4T1 cells infiltrated the scaffolds pores and constructed a 3D microenvironment. Furthermore, 3D cultured tumor cells showed a slower proliferation rate, increased levels of survival to the X-ray irradiation, and enhanced resistance to chemotherapy drugs in comparison with 2D plate cultures. Transfer of extracted cells to the mice caused enhanced tumor volume and decreased life span. This study indicated that collagen–chitosan nanoscaffolds provide a suitable model of tumor that would be appropriate for tumor studies.

  18. Tumor cell culture on collagen-chitosan scaffolds as three-dimensional tumor model: A suitable model for tumor studies.

    Science.gov (United States)

    Mahmoudzadeh, Aziz; Mohammadpour, Hemn

    2016-07-01

    Tumor cells naturally live in three-dimensional (3D) microenvironments, while common laboratory tests and evaluations are done in two-dimensional (2D) plates. This study examined the impact of cultured 4T1 cancer cells in a 3D collagen-chitosan scaffold compared with 2D plate cultures. Collagen-chitosan scaffolds were provided and passed confirmatory tests. 4T1 tumor cells were cultured on scaffolds and then tumor cells growth rate, resistance to X-ray radiation, and cyclophosphamide as a chemotherapy drug were analyzed. Furthermore, 4T1 cells were extracted from the scaffold model and were injected into the mice. Tumor growth rate, survival rate, and systemic immune responses were evaluated. Our results showed that 4T1 cells infiltrated the scaffolds pores and constructed a 3D microenvironment. Furthermore, 3D cultured tumor cells showed a slower proliferation rate, increased levels of survival to the X-ray irradiation, and enhanced resistance to chemotherapy drugs in comparison with 2D plate cultures. Transfer of extracted cells to the mice caused enhanced tumor volume and decreased life span. This study indicated that collagen-chitosan nanoscaffolds provide a suitable model of tumor that would be appropriate for tumor studies. Copyright © 2016. Published by Elsevier B.V.

  19. Tumor Response to Radiotherapy Regulated by Endothelial Cell Apoptosis

    Science.gov (United States)

    Garcia-Barros, Monica; Paris, Francois; Cordon-Cardo, Carlos; Lyden, David; Rafii, Shahin; Haimovitz-Friedman, Adriana; Fuks, Zvi; Kolesnick, Richard

    2003-05-01

    About 50% of cancer patients receive radiation therapy. Here we investigated the hypothesis that tumor response to radiation is determined not only by tumor cell phenotype but also by microvascular sensitivity. MCA/129 fibrosarcomas and B16F1 melanomas grown in apoptosis-resistant acid sphingomyelinase (asmase)-deficient or Bax-deficient mice displayed markedly reduced baseline microvascular endothelial apoptosis and grew 200 to 400% faster than tumors on wild-type microvasculature. Thus, endothelial apoptosis is a homeostatic factor regulating angiogenesis-dependent tumor growth. Moreover, these tumors exhibited reduced endothelial apoptosis upon irradiation and, unlike tumors in wild-type mice, they were resistant to single-dose radiation up to 20 grays (Gy). These studies indicate that microvascular damage regulates tumor cell response to radiation at the clinically relevant dose range.

  20. Mechanisms associated with the expression of cisplatin resistance in a human ovarian tumor cell line following exposure to fractionated x-irradiation in vitro

    International Nuclear Information System (INIS)

    Dempke, W.C.M.; Shellard, S.A.; Hosking, L.K.; Hill, B.T.

    1992-01-01

    Interactions between cisplatin (CDDP) and irradiation are of potential significance for the combined modality treatment of cancer. To identify parameters associated with CDDP resistance, the human ovarian carcinoma cell line SK-OV-3/P was pre-exposed to fractionated X-irradiation in vitro. The resultant subline (SK-OV-3/DXR-10) proved 2-fold resistant to CDDP, but not to acute X-irradiation. Consistent with unaltered dihydrofolate reductase and thymidylate synthase activities, SK-OV-3/DXR-10 cells were neither cross-resistant to methotrexate nor to 5-fluorouracil. Verapamil significantly enhanced CDDP-induced cytotoxicity in the resistant DXR-10 subline, but not in the parental cells. Resistance in the SK-OV-3/DXR-10 cells was associated with significantly decreased cisplatin uptake. After an 18 h post-treatment incubation the parental cell line appeared proficient in the removal of the intrastrand adduct Pt-AG, but deficient in removing the major adduct Pt-GG and the difunctional Pt-(GMP) 2 lesion, whilst the DXR-10 resistant subline appeared proficient in removal of all four Pt-DNA adducts. DNA polymerases α and β activities, however, were comparable in both cell lines. These data implicate both enhanced repair and increased tolerance of DNA damage as mechanisms of resistance to CDDP resulting from in vitro exposure of a human ovarian carcinoma cell line to fractionated X-irradiation. (author)

  1. Granular Cell Tumor

    African Journals Online (AJOL)

    1). Her packed cell volume was 40%, she was system, gastro-intestinal tract, brain, heart, and negative to human immunodeficiency virus. 2 female reproductive . ... histocytes and neurons at various times. They granules. The granules are probably of lysosmal were consequently termed granular cell origin and contain ...

  2. Smac Mimetic Bypasses Apoptosis Resistance in FADD- or Caspase-8-Deficient Cells by Priming for Tumor Necrosis Factor α-Induced Necroptosis

    Directory of Open Access Journals (Sweden)

    Bram Laukens

    2011-10-01

    Full Text Available Searching for new strategies to bypass apoptosis resistance, we investigated the potential of the Smac mimetic BV6 in Jurkat leukemia cells deficient in key molecules of the death receptor pathway. Here, we demonstrate for the first time that Smac mimetic primes apoptosis-resistant, FADD- or caspase-8-deficient leukemia cells for TNFα-induced necroptosis in a synergistic manner. In contrast to TNFα, Smac mimetic significantly enhances CD95-induced apoptosis in wild-type but not in FADD-deficient cells. Interestingly, Smac mimetic- and TNFα-mediated cell death occurs without characteristic features of apoptosis (i.e., caspase activation, DNA fragmentation in FADD-deficient cells. By comparison, Smac mimetic and TNFα trigger activation of caspase-8, -9, and -3 and DNA fragmentation in wild-type cells. Consistently, the caspase inhibitor zVAD.fmk fails to block Smac mimetic- and TNFα-triggered cell death in FADD- or caspase-8-deficient cells, while it confers protection in wild-type cells. By comparison, necrostatin-1, an RIP1 kinase inhibitor, abolishes Smac mimetic- and TNFα-induced cell death in FADD- or caspase-8-deficient. Thus, Smac mimetic enhances TNFα-induced cell death in leukemia cells via two distinct pathways in a context-dependent manner: it primes apoptosis-resistant cells lacking FADD or caspase-8 to TNFα-induced, RIP1-dependent and caspase-independent necroptosis, whereas it sensitizes apoptosis-proficient cells to TNFα-mediated, caspase-dependent apoptosis. These findings have important implications for the therapeutic exploitation of necroptosis as an alternative cell death program to overcome apoptosis resistance.

  3. Studies on cross-immunity among syngeneic tumors by immunization with gamma-irradiated tumor cells

    International Nuclear Information System (INIS)

    Ito, Izumi

    1977-01-01

    In order to clarify whether cross-immunity among 3-methyl-cholanthrene (MCA)-induced sarcomas in C3H/He mice can be established or not, transplantations of syngeneic tumors were carried out in mice immunized with gamma-irradiated (13,000 rad 60 Co) tumor cells and in those immunized with living tumor cells thereafter. The following results were obtained. By using immunizing procedure with only gamma-irradiated tumor cells, a pair of tumors originating from one and the same mouse showed cross-resistance to each other. However, no such evidence was seen among tumors originating from different mice. Cross-immunity among syngeneic tumors originating from different mice could be clearly observed, when immunizing procedure using living tumor cells was added after the treatment with gamma-irradiated tumor cells. It was considered that common antigenicity among MCA-induced sarcoma cells was decreased by gamma-irradiation and that individual differences of tumor antigenecity were shown distinctly under such conditions. (auth.)

  4. Quantitative analysis of MDR1 (multidrug resistance) gene expression in human tumors by polymerase chain reaction

    International Nuclear Information System (INIS)

    Noonan, K.E.; Beck, C.; Holzmayer, T.A.; Chin, J.E.; Roninson, I.B.; Wunder, J.S.; Andrulis, I.L.; Gazdar, A.F.; Willman, C.L.; Griffith, B.; Von Hoff, D.D.

    1990-01-01

    The resistance of tumor cells ot chemotheraprutic drugs is a major obstacle to successful cancer chemotherapy. In human cells, expression of the MDR1 gene, encoding a transmembrane efflux pump (P-glycoprotein), leads to decreased intracellular accumulation and resistance to a variety of lipophilic drugs (multidrug resistance; MDR). The levels of MDR in cell lines selected in bitro have been shown to correlate with the steady-state levels of MDR1 mRNA and P-glycoprotein. In cells with a severalfold increase in cellular drug resistance, MDR1 expression levels are close to the limits of detection by conventional assays. MDR1 expression has been frequently observed in human tumors after chemotherapy and in some but not all types of clinically refactory tumors untreated with chemotherapeutic drugs. The authors have devised a highly sensitive, specific, and quantitative protocol for measuring the levels of MDR1 mRNA in clincal samples, based on the polymerase chain reaction. They have used this assay to measure MDR1 gene expression in MDR cell lines and >300 normal tissues, tumor-derived cell lines, and clinical specimens of untreated tumors of the types in which MDR1 expression was rarely observed by standard assays. Low levels of MDR1 expression were found by polymerase chain reaction in most solid tumors and leukemias tested. The frequency of samples without detectable MDR1 expression varied among different types of tumors; MDR1-negative samples were ost common among tumor types known to be relatively responsive to chemotherapy

  5. DNA repair rate and etoposide (VP16) resistance of tumor cell subpopulations derived from a single human small cell lung cancer

    DEFF Research Database (Denmark)

    Hansen, Lasse Tengbjerg; Lundin, Cecilia; Helleday, Thomas

    2003-01-01

    being VP16 resistant. In order to explain the VP16 resistant phenotype several mechanisms where considered. The p53 status, P-glycoprotein, MRP, topoisomerase IIalpha, and Mre11 protein levels, as well as growth kinetics, provided no explanations of the observed VP16 resistance. In contrast...

  6. Tumor-specific CD4+ T cells develop cytotoxic activity and eliminate virus-induced tumor cells in the absence of regulatory T cells.

    Science.gov (United States)

    Akhmetzyanova, Ilseyar; Zelinskyy, Gennadiy; Schimmer, Simone; Brandau, Sven; Altenhoff, Petra; Sparwasser, Tim; Dittmer, Ulf

    2013-02-01

    The important role of tumor-specific cytotoxic CD8(+) T cells is well defined in the immune control of the tumors, but the role of effector CD4(+) T cells is poorly understood. In the current research, we have used a murine retrovirus-induced tumor cell line of C57BL/6 mouse origin, namely FBL-3 cells, as a model to study basic mechanisms of immunological control and escape during tumor formation. This study shows that tumor-specific CD4(+) T cells are able to protect against virus-induced tumor cells. We show here that there is an expansion of tumor-specific CD4(+) T cells producing cytokines and cytotoxic molecule granzyme B (GzmB) in the early phase of tumor growth. Importantly, we demonstrate that in vivo depletion of regulatory T cells (Tregs) and CD8(+) T cells in FBL-3-bearing DEREG transgenic mice augments IL-2 and GzmB production by CD4(+) T cells and increases FV-specific CD4(+) T-cell effector and cytotoxic responses leading to the complete tumor regression. Therefore, the capacity to reject tumor acquired by tumor-reactive CD4(+) T cells largely depends on the direct suppressive activity of Tregs. We suggest that a cytotoxic CD4(+) T-cell immune response may be induced to enhance resistance against oncovirus-associated tumors.

  7. Antiangiogenic Therapy and Mechanisms of Tumor Resistance in Malignant Glioma

    Directory of Open Access Journals (Sweden)

    Ruman Rahman

    2010-01-01

    Full Text Available Despite advances in surgery, radiation therapy, and chemotherapeutics, patients with malignant glioma have a dismal prognosis. The formations of aberrant tumour vasculature and glioma cell invasion are major obstacles for effective treatment. Angiogenesis is a key event in the progression of malignant gliomas, a process involving endothelial cell proliferation, migration, reorganization of extracellular matrix and tube formation. Such processes are regulated by the homeostatic balance between proangiogenic and antiangiogenic factors, most notably vascular endothelial growth factors (VEGFs produced by glioma cells. Current strategies targeting VEGF-VEGF receptor signal transduction pathways, though effective in normalizing abnormal tumor vasculature, eventually result in tumor resistance whereby a highly infiltrative and invasive phenotype may be adopted. Here we review recent anti-angiogenic therapy for malignant glioma and highlight implantable devices and nano/microparticles as next-generation methods for chemotherapeutic delivery. Intrinsic and adaptive modes of glioma resistance to anti-angiogenic therapy will be discussed with particular focus on the glioma stem cell paradigm.

  8. Tumor cell proliferation kinetics and tumor growth rate

    Energy Technology Data Exchange (ETDEWEB)

    Tubiana, M

    1989-01-01

    The present knowledge on the growth rate and the proliferation kinetics of human tumor is based on the measurement of the tumor doubling times (DT) in several hundred patients and on the determination of the proportion of proliferating cells with radioactive thymidine or by flow cytometry in large numbers of patients. The results show that the DT of human tumor varies widely, from less than one week to over one year with a median value of approximately 2 months. The DTs are significantly correlated with the histological type. They depend upon (1) the duration of the cell cycle whose mean duration is 2 days with small variations from tumor to tumor, (2) the proportion of proliferating cells and consequently the cell birth rate which varies widely among tumors and which is significantly correlated to the DT, (3) the cell loss factors which also vary widely and which are the greatest when proliferation is most intensive. These studies have several clinical implications: (a) they have further increased our understanding of the natural history of human tumor, (b) they have therapeutic implications since tumor responsiveness and curability by radiation and drugs are strongly influenced by the cell kinetic parameters of the tumor, (c) the proportion of proliferating cells is of great prognostic value in several types of human cancers. The investigation of the molecular defects, which are correlated with the perturbation of control of cell proliferation, should lead to significant fundamental and therapeutic advances. (orig.).

  9. Multiparametric classification links tumor microenvironments with tumor cell phenotype.

    Directory of Open Access Journals (Sweden)

    Bojana Gligorijevic

    2014-11-01

    Full Text Available While it has been established that a number of microenvironment components can affect the likelihood of metastasis, the link between microenvironment and tumor cell phenotypes is poorly understood. Here we have examined microenvironment control over two different tumor cell motility phenotypes required for metastasis. By high-resolution multiphoton microscopy of mammary carcinoma in mice, we detected two phenotypes of motile tumor cells, different in locomotion speed. Only slower tumor cells exhibited protrusions with molecular, morphological, and functional characteristics associated with invadopodia. Each region in the primary tumor exhibited either fast- or slow-locomotion. To understand how the tumor microenvironment controls invadopodium formation and tumor cell locomotion, we systematically analyzed components of the microenvironment previously associated with cell invasion and migration. No single microenvironmental property was able to predict the locations of tumor cell phenotypes in the tumor if used in isolation or combined linearly. To solve this, we utilized the support vector machine (SVM algorithm to classify phenotypes in a nonlinear fashion. This approach identified conditions that promoted either motility phenotype. We then demonstrated that varying one of the conditions may change tumor cell behavior only in a context-dependent manner. In addition, to establish the link between phenotypes and cell fates, we photoconverted and monitored the fate of tumor cells in different microenvironments, finding that only tumor cells in the invadopodium-rich microenvironments degraded extracellular matrix (ECM and disseminated. The number of invadopodia positively correlated with degradation, while the inhibiting metalloproteases eliminated degradation and lung metastasis, consistent with a direct link among invadopodia, ECM degradation, and metastasis. We have detected and characterized two phenotypes of motile tumor cells in vivo, which

  10. Patient-Derived Antibody Targets Tumor Cells

    Science.gov (United States)

    An NCI Cancer Currents blog on an antibody derived from patients that killed tumor cells in cell lines of several cancer types and slowed tumor growth in mouse models of brain and lung cancer without evidence of side effects.

  11. Circulating Tumor Cells Measurements in Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Franck Chiappini

    2012-01-01

    Full Text Available Liver cancer is the fifth most common cancer in men and the seventh in women. During the past 20 years, the incidence of HCC has tripled while the 5-year survival rate has remained below 12%. The presence of circulating tumor cells (CTC reflects the aggressiveness nature of a tumor. Many attempts have been made to develop assays that reliably detect and enumerate the CTC during the development of the HCC. In this case, the challenges are (1 there are few markers specific to the HCC (tumor cells versus nontumor cells and (2 they can be used to quantify the number of CTC in the bloodstream. Another technical challenge consists of finding few CTC mixed with million leukocytes and billion erythrocytes. CTC detection and identification can be used to estimate prognosis and may serve as an early marker to assess antitumor activity of treatment. CTC can also be used to predict progression-free survival and overall survival. CTC are an interesting source of biological information in order to understand dissemination, drug resistance, and treatment-induced cell death. Our aim is to review and analyze the different new methods existing to detect, enumerate, and characterize the CTC in the peripheral circulation of patients with HCC.

  12. Intrinsic radiation resistance in human chondrosarcoma cells

    International Nuclear Information System (INIS)

    Moussavi-Harami, Farid; Mollano, Anthony; Martin, James A.; Ayoob, Andrew; Domann, Frederick E.; Gitelis, Steven; Buckwalter, Joseph A.

    2006-01-01

    Human chondrosarcomas rarely respond to radiation treatment, limiting the options for eradication of these tumors. The basis of radiation resistance in chondrosarcomas remains obscure. In normal cells radiation induces DNA damage that leads to growth arrest or death. However, cells that lack cell cycle control mechanisms needed for these responses show intrinsic radiation resistance. In previous work, we identified immortalized human chondrosarcoma cell lines that lacked p16 ink4a , one of the major tumor suppressor proteins that regulate the cell cycle. We hypothesized that the absence of p16 ink4a contributes to the intrinsic radiation resistance of chondrosarcomas and that restoring p16 ink4a expression would increase their radiation sensitivity. To test this we determined the effects of ectopic p16 ink4a expression on chondrosarcoma cell resistance to low-dose γ-irradiation (1-5 Gy). p16 ink4a expression significantly increased radiation sensitivity in clonogenic assays. Apoptosis did not increase significantly with radiation and was unaffected by p16 ink4a transduction of chondrosarcoma cells, indicating that mitotic catastrophe, rather than programmed cell death, was the predominant radiation effect. These results support the hypothesis that p16 ink4a plays a role in the radiation resistance of chondrosarcoma cell lines and suggests that restoring p16 expression will improve the radiation sensitivity of human chondrosarcomas

  13. Peripheral dentinogenic ghost cell tumor

    Directory of Open Access Journals (Sweden)

    Sushant S Kamat

    2013-01-01

    Full Text Available Dentinogenic ghost cell tumors (DGCT are uncommon lesions mainly with rare peripheral types. This report presents a case of peripheral DGCT on the left side of the mandibular alveolar ridge of a heavy smoker, a 68-year-old man, with main presenting feature as a mild pain. Submandibular lymphadenopathy and radiological "saucerization" were evident. Differential diagnosis included fibroma, neurofibroma, peripheral ameloblastoma, peripheral odontogenic fibroma, and peripheral giant cell granuloma. Histologically, ameloblastoma-like epithelial elements were seen in association with grouped ghost cells. Proliferating polyhedral cells and stellate reticulum-like cells with various densities were spread over a wide range of the field. The lesion was curetted and after 2 years of follow up, it did not recur.

  14. Human neutrophils facilitate tumor cell transendothelial migration.

    LENUS (Irish Health Repository)

    Wu, Q D

    2012-02-03

    Tumor cell extravasation plays a key role in tumor metastasis. However, the precise mechanisms by which tumor cells migrate through normal vascular endothelium remain unclear. In this study, using an in vitro transendothelial migration model, we show that human polymorphonuclear neutrophils (PMN) assist the human breast tumor cell line MDA-MB-231 to cross the endothelial barrier. We found that tumor-conditioned medium (TCM) downregulated PMN cytocidal function, delayed PMN apoptosis, and concomitantly upregulated PMN adhesion molecule expression. These PMN treated with TCM attached to tumor cells and facilitated tumor cell migration through different endothelial monolayers. In contrast, MDA-MB-231 cells alone did not transmigrate. FACScan analysis revealed that these tumor cells expressed high levels of intercellular adhesion molecule-1 (ICAM-1) but did not express CD11a, CD11b, or CD18. Blockage of CD11b and CD18 on PMN and of ICAM-1 on MDA-MB-231 cells significantly attenuated TCM-treated, PMN-mediated tumor cell migration. These tumor cells still possessed the ability to proliferate after PMN-assisted transmigration. These results indicate that TCM-treated PMN may serve as a carrier to assist tumor cell transendothelial migration and suggest that tumor cells can exploit PMN and alter their function to facilitate their extravasation.

  15. Combination immunotherapy with radiation and CpG-based tumor vaccination for the eradication of radio- and immuno-resistant lung carcinoma cells

    International Nuclear Information System (INIS)

    Chamoto, Kenji; Wakita, Daiko; Takeshima, Tsuguhide

    2009-01-01

    Unmethylated cytosine-phosphorothioate-guanine containing oligodeoxynucleotides (CpG-ODN) is known as a ligand of toll-like receptor 9 (TLR9), which selectively activates type-1 immunity. We have already reported that the vaccination of tumor-bearing mice with liposome-CpG coencapsulated with model-tumor antigen, ovalbumin (OVA) (CpG+OVA-liposome) caused complete cure of the mice bearing OVA-expressing EG-7 lymphoma cells. However, the same therapy was not effective to eradicate Lewis lung carcinoma (LLC)-OVA-carcinoma. To overcome the refractoriness of LLC-OVA, we tried the combination therapy of radiation with CpG-based tumor vaccination. When LLC-OVA-carcinoma intradermally (i.d.) injected into C57BL/6 became palpable (7-8 mm), the mice were irradiated twice with a dose of 14 Gy at intervals of 24 h. After the second radiation, CpG+OVA-liposome was i.d. administered near the draining lymph node (DLN) of the tumor mass. The tumor growth of mice treated with radiation plus CpG+OVA-liposome was greatly inhibited and approximately 60% of mice treated were completely cured. Moreover, the combined therapy with radiation and CpG+OVA-liposome allowed the augmented induction of OVA-tetramer + LLC-OVA-specific cytotoxic T lymphocyte (CTL) in DLN of tumor-bearing mice. These results indicate that the combined therapy of radiation with CpG-based tumor vaccine is a useful strategy to eradicate intractable carcinoma. (author)

  16. Tumor stem cells: A new approach for tumor therapy (Review)

    Science.gov (United States)

    MENG, MIN; ZHAO, XIN-HAN; NING, QIAN; HOU, LEI; XIN, GUO-HONG; LIU, LI-FENG

    2012-01-01

    Recent studies have demonstrated the existence of a minority of tumor cells possessing the stem cell properties of self-renewal and differentiation in leukemia and several solid tumors. However, these cells do not possess the normal regulatory mechanisms of stem cells. Following transplantation, they are capable of initiating tumorigenesis and are therefore known as ‘tumor stem cells’. Cellular origin analysis of tumor stem cells has resulted in three hypotheses: Embryonal rest hypothesis, anaplasia and maturation arrest. Several signaling pathways which are involved in carcinogenesis, including Wnt/β-catenin, Notch and Oct-4 signaling pathways are crucial in normal stem cell self-renewal decisions, suggesting that breakdown in the regulation of self-renewal may be a key event in the development of tumors. Thus, tumors can be regarded as an abnormal organ in which stem cells have escaped from the normal constraints on self-renewal, thus, leading to abnormally differentiated tumor cells that lose the ability to form tumors. This new model for maligancies has significance for clinical research and treatment. PMID:22844351

  17. Plasmonic Nanobubbles Rapidly Detect and Destroy Drug-Resistant Tumors

    Science.gov (United States)

    Lukianova-Hleb, Ekaterina Y.; Ren, Xiaoyang; Townley, Debra; Wu, Xiangwei; Kupferman, Michael E.; Lapotko, Dmitri O.

    2012-01-01

    The resistance of residual cancer cells after oncological resection to adjuvant chemoradiotherapies results in both high recurrence rates and high non-specific tissue toxicity, thus preventing the successful treatment of such cancers as head and neck squamous cell carcinoma (HNSCC). The patients' survival rate and quality of life therefore depend upon the efficacy, selectivity and low non-specific toxicity of the adjuvant treatment. We report a novel, theranostic in vivo technology that unites both the acoustic diagnostics and guided intracellular delivery of anti-tumor drug (liposome-encapsulated doxorubicin, Doxil) in one rapid process, namely a pulsed laser-activated plasmonic nanobubble (PNB). HNSCC-bearing mice were treated with gold nanoparticle conjugates, Doxil, and single near-infrared laser pulses of low energy. Tumor-specific clusters of gold nanoparticles (solid gold spheres) converted the optical pulses into localized PNBs. The acoustic signals of the PNB detected the tumor with high specificity and sensitivity. The mechanical impact of the PNB, co-localized with Doxil liposomes, selectively ejected the drug into the cytoplasm of cancer cells. Cancer cell-specific generation of PNBs and their intracellular co-localization with Doxil improved the in vivo therapeutic efficacy from 5-7% for administration of only Doxil or PNBs alone to 90% thus demonstrating the synergistic therapeutic effect of the PNB-based intracellular drug release. This mechanism also reduced the non-specific toxicity of Doxil below a detectable level and the treatment time to less than one minute. Thus PNBs combine highly sensitive diagnosis, overcome drug resistance and minimize non-specific toxicity in a single rapid theranostic procedure for intra-operative treatment. PMID:23139725

  18. Neuroblastoma cell lines contain pluripotent tumor initiating cells that are susceptible to a targeted oncolytic virus.

    Directory of Open Access Journals (Sweden)

    Yonatan Y Mahller

    Full Text Available Although disease remission can frequently be achieved for patients with neuroblastoma, relapse is common. The cancer stem cell theory suggests that rare tumorigenic cells, resistant to conventional therapy, are responsible for relapse. If true for neuroblastoma, improved cure rates may only be achieved via identification and therapeutic targeting of the neuroblastoma tumor initiating cell. Based on cues from normal stem cells, evidence for tumor populating progenitor cells has been found in a variety of cancers.Four of eight human neuroblastoma cell lines formed tumorspheres in neural stem cell media, and all contained some cells that expressed neurogenic stem cell markers including CD133, ABCG2, and nestin. Three lines tested could be induced into multi-lineage differentiation. LA-N-5 spheres were further studied and showed a verapamil-sensitive side population, relative resistance to doxorubicin, and CD133+ cells showed increased sphere formation and tumorigenicity. Oncolytic viruses, engineered to be clinically safe by genetic mutation, are emerging as next generation anticancer therapeutics. Because oncolytic viruses circumvent typical drug-resistance mechanisms, they may represent an effective therapy for chemotherapy-resistant tumor initiating cells. A Nestin-targeted oncolytic herpes simplex virus efficiently replicated within and killed neuroblastoma tumor initiating cells preventing their ability to form tumors in athymic nude mice.These results suggest that human neuroblastoma contains tumor initiating cells that may be effectively targeted by an oncolytic virus.

  19. Cancer stem cells and the tumor microenvironment: interplay in tumor heterogeneity.

    Science.gov (United States)

    Albini, Adriana; Bruno, Antonino; Gallo, Cristina; Pajardi, Giorgio; Noonan, Douglas M; Dallaglio, Katiuscia

    2015-01-01

    Tumor cells able to recapitulate tumor heterogeneity have been tracked, isolated and characterized in different tumor types, and are commonly named Cancer Stem Cells or Cancer Initiating Cells (CSC/CIC). CSC/CIC are disseminated in the tumor mass and are resistant to anti-cancer therapies and adverse conditions. They are able to divide into another stem cell and a "proliferating" cancer cell. They appear to be responsible for disease recurrence and metastatic dissemination even after apparent eradication of the primary tumor. The modulation of CSC/CIC activities by the tumor microenvironment (TUMIC) is still poorly known. CSC/CIC may mutually interact with the TUMIC in a special and unique manner depending on the TUMIC cells or proteins encountered. The TUMIC consists of extracellular matrix components as well as cellular players among which endothelial, stromal and immune cells, providing and responding to signals to/from the CSC/CIC. This interplay can contribute to the mechanisms through which CSC/CIC may reside in a dormant state in a tissue for years, later giving rise to tumor recurrence or metastasis in patients. Different TUMIC components, including the connective tissue, can differentially activate CIC/CSC in different areas of a tumor and contribute to the generation of cancer heterogeneity. Here, we review possible networking activities between the different components of the tumor microenvironment and CSC/CIC, with a focus on its role in tumor heterogeneity and progression. We also summarize novel therapeutic options that could target both CSC/CIC and the microenvironment to elude resistance mechanisms activated by CSC/CIC, responsible for disease recurrence and metastases.

  20. Sox2, a stemness gene, regulates tumor-initiating and drug-resistant properties in CD133-positive glioblastoma stem cells

    Directory of Open Access Journals (Sweden)

    Wen-Shin Song

    2016-10-01

    Conclusion: SOX2 plays a crucial role in regulating tumorigenicity in CD133+ GBM cells. Our results not only revealed the genetic plasticity contributing to drug resistance and stemness but also demonstrated the dominant role of SOX2 in maintenance of GBM CSCs, which may provide a novel therapeutic target to overcome the conundrum of poor survival of brain cancers.

  1. AR-V7 in circulating tumor cells cluster as a predictive biomarker of abiraterone acetate and enzalutamide treatment in castration-resistant prostate cancer patients.

    Science.gov (United States)

    Okegawa, Takatsugu; Ninomiya, Naoki; Masuda, Kazuki; Nakamura, Yu; Tambo, Mitsuhiro; Nutahara, Kikuo

    2018-06-01

    We examined whether androgen receptor splice variant 7 (AR-V7) in circulating tumor cell(CTC)clusters can be used to predict survival in patients with bone metastatic castration resistant-prostate cancer (mCRPC) treated with abiraterone or enzalutamide. We retrospectively enrolled 98 patients with CRPC on abiraterone or enzalutamide, and investigated the prognostic value of CTC cluster detection (+ v -) and AR-V7 detection (+ v -) using a CTC cluster detection - based AR-V7 mRNA assay. We examined ≤50% prostate-specific antigen (PSA) responses, PSA progression-free survival (PSA-PFS), clinical and radiological progression-free survival (radiologic PSF), and overall survival (OS). We then assessed whether AR-V7 expression in CTC clusters identified after On-chip multi-imaging flow cytometry was related to disease progression and survival after first-line systemic therapy. All abiraterone-treated or enzalutamide-treated patients received prior docetaxel. The median follow-up was 20.7 (range: 3.0-37.0) months in the abiraterone and enzalutamide cohorts, respectively. Forty-nine of the 98 men (50.0%) were CTC cluster (-), 23 of the 98 men (23.5%) were CTC cluster(+)/AR-V7(-), and 26 of the 98 men (26.5%) were CTC cluster(+)/AR-V7(+). CTC cluster(+)/AR-V7(+) patients were more likely to have EOD ≥3 at diagnosis (P = 0.003), pain (P = 0.023), higher alkaline phosphatase levels (P cluster(+), CTC cluster(+)/AR-V7(-), and ALP >UNL were independently associated with a poor PSA-PFS, radiographic PFS, and OS in abiraterone-treated patients and enzalutamide-treated patients. The CTC clusters and AR-V7-positive CTC clusters detected were important for assessing the response to abiraterone or enzalutamide therapy and for predicting disease outcome. © 2018 Wiley Periodicals, Inc.

  2. Erlotinib is a viable treatment for tumors with acquired resistance to cetuximab

    Science.gov (United States)

    Brand, Toni M; Dunn, Emily F; Iida, Mari; Myers, Rebecca A; Kostopoulos, Kellie T; Li, Chunrong; Peet, Chimera R

    2011-01-01

    The epidermal growth factor receptor (EGFR) is an ubiquitously expressed receptor tyrosine kinase (RTK) and is recognized as a key mediator of tumorigenesis in many human tumors. Currently there are five EGFR inhibitors used in oncology, two monoclonal antibodies (panitumumab and cetuximab) and three tyrosine kinase inhibitors (erlotinib, gefitinib and lapatinib). Both strategies of EGFR inhibition have demonstrated clinical success; however, many tumors remain non-responsive or acquire resistance during therapy. To explore potential molecular mechanisms of acquired resistance to cetuximab we previously established a series of cetuximab-resistant clones by chronically exposing the NCI-H226 NSCLC cell line to escalating doses of cetuximab. Cetuximab-resistant clones exhibited a dramatic increase in the activation of EGFR, HER2 and HER3 receptors as well as increased signaling through the MAP K and AKT pathways. RNAi studies demonstrated dependence of cetuximab-resistant clones on the EGFR signaling network. These findings prompted investigation on whether or not cells with acquired resistance to cetuximab would be sensitive to the EGFR targeted TKI erlotinib. In vitro, erlotinib was able to decrease signaling through the EGFR axis, decrease cellular proliferation and induce apoptosis. To determine if erlotinib could have therapeutic benefit in vivo, we established cetuximab-resistant NCI-H226 mouse xenografts, and subsequently treated them with erlotinib. Mice harboring cetuximab-resistant tumors treated with erlotinib exhibited either a tumor regression or growth delay as compared with vehicle controls. Analysis of the erlotinib treated tumors demonstrated a decrease in cell proliferation and increased rates of apoptosis. The work presented herein suggests that (1) cells with acquired resistance to cetuximab maintain their dependence on EGFR and (2) tumors developing resistance to cetuximab can benefit from subsequent treatment with erlotinib, providing rationale

  3. Experimental rat lung tumor model with intrabronchial tumor cell implantation.

    Science.gov (United States)

    Gomes Neto, Antero; Simão, Antônio Felipe Leite; Miranda, Samuel de Paula; Mourão, Lívia Talita Cajaseiras; Bezerra, Nilfácio Prado; Almeida, Paulo Roberto Carvalho de; Ribeiro, Ronaldo de Albuquerque

    2008-01-01

    The objective of this study was to develop a rat lung tumor model for anticancer drug testing. Sixty-two female Wistar rats weighing 208 +/- 20 g were anesthetized intraperitoneally with 2.5% tribromoethanol (1 ml/100 g live weight), tracheotomized and intubated with an ultrafine catheter for inoculation with Walker's tumor cells. In the first step of the experiment, a technique was established for intrabronchial implantation of 10(5) to 5 x 10(5) tumor cells, and the tumor take rate was determined. The second stage consisted of determining tumor volume, correlating findings from high-resolution computed tomography (HRCT) with findings from necropsia and determining time of survival. The tumor take rate was 94.7% for implants with 4 x 10(5) tumor cells, HRCT and necropsia findings matched closely (r=0.953; p<0.0001), the median time of survival was 11 days, and surgical mortality was 4.8%. The present rat lung tumor model was shown to be feasible: the take rate was high, surgical mortality was negligible and the procedure was simple to perform and easily reproduced. HRCT was found to be a highly accurate tool for tumor diagnosis, localization and measurement and may be recommended for monitoring tumor growth in this model.

  4. [Regression and therapy-resistance of primary liver tumors and liver metastases after regional chemotherapy and local tumor ablation].

    Science.gov (United States)

    Fischer, H-P

    2005-05-01

    High dosage regional chemotherapy, chemoembolization and other methods of regional treatment are commonly used to treat unresectable primary liver malignancies and liver metastases. In liver malignancies of childhood neoadjuvant chemotherapy is successfully combined with surgical treatment. Chemotherapy and local tumor ablation lead to characteristic histomorphologic changes: Complete destruction of the tumor tissue and its vascular bed is followed by encapsulated necroses. After selective eradication of the tumor cells under preservation of the fibrovasular bed the tumor is replaced by hypocellular edematous and fibrotic tissue. If completely damaged tumor tissue is absorbed quickly, the tumor area is replaced by regenerating liver tissue. Obliterating fibrohyalinosis of tumor vessels, and perivascular edema or necrosis indicate tissue damage along the vascular bed. Degenerative pleomorphism of tumor cells, steatosis, hydropic swelling and Malloryhyalin in HCC can represent cytologic findings of cytotoxic cellular damage. Macroscopic type of HCC influences significantly the response to treatment. Multinodular HCC often contain viable tumor nodules close to destroyed nodules after treatment. Encapsulated uninodular tumors undergo complete necrosis much easier. Large size and a tumor capsule limitate the effect of percutaneous injection of ethanol into HCC. In carcinomas with an infiltrating border, especially in metastases of adenocarcinomas and hepatic cholangiocarcinoma cytostatic treatment damages the tumor tissue mainly in the periphery. Nevertheless the infiltrating rim, portal veins, lymphatic spaces and bile ducts as well as the angle between liver capsule, tumor nodule and bordering parenchyma are the main refugees of viable tumor tissue even after high dosage regional chemotherapy. This local resistance is caused by special local conditions of vascularization and perfusion. These residues are the source of local tumor progression and distant metastases

  5. Nanoparticle-mediated combination chemotherapy and photodynamic therapy overcomes tumor drug resistance.

    Science.gov (United States)

    Khdair, Ayman; Chen, Di; Patil, Yogesh; Ma, Linan; Dou, Q Ping; Shekhar, Malathy P V; Panyam, Jayanth

    2010-01-25

    Tumor drug resistance significantly limits the success of chemotherapy in the clinic. Tumor cells utilize multiple mechanisms to prevent the accumulation of anticancer drugs at their intracellular site of action. In this study, we investigated the anticancer efficacy of doxorubicin in combination with photodynamic therapy using methylene blue in a drug-resistant mouse tumor model. Surfactant-polymer hybrid nanoparticles formulated using an anionic surfactant, Aerosol-OT (AOT), and a naturally occurring polysaccharide polymer, sodium alginate, were used for synchronized delivery of the two drugs. Balb/c mice bearing syngeneic JC tumors (mammary adenocarcinoma) were used as a drug-resistant tumor model. Nanoparticle-mediated combination therapy significantly inhibited tumor growth and improved animal survival. Nanoparticle-mediated combination treatment resulted in enhanced tumor accumulation of both doxorubicin and methylene blue, significant inhibition of tumor cell proliferation, and increased induction of apoptosis. These data suggest that nanoparticle-mediated combination chemotherapy and photodynamic therapy using doxorubicin and methylene blue has significant therapeutic potential against drug-resistant tumors. Copyright 2009 Elsevier B.V. All rights reserved.

  6. Multidrug-resistant hepatocellular carcinoma cells are enriched for ...

    African Journals Online (AJOL)

    Chemotherapy is a main treatment for cancer, while multidrug-resistance is the main reason for chemotherapy failure, and tumor relapse and metastasis. Cancer stem cells or cancer stem-like cells (CSCs) are a small subset of cancer cells, which may be inherently resistant to the cytotoxic effect of chemotherapy.

  7. Drug resistance following irradiation of RIF-1 tumors: Influence of the interval between irradiation and drug treatment

    International Nuclear Information System (INIS)

    Hopwood, L.E.; Davies, B.M.; Moulder, J.E.

    1990-01-01

    RIF-1 tumors contain a small number of cells (1 to 100 per 10(6) cells) that are resistant to 5-fluorouracil, methotrexate, or adriamycin. The frequency of drug-resistant cells among individual untreated tumors is highly variable. Radiation, delivered in vivo at doses of 3 to 12 Gy, increases the frequency of methotrexate- and 5-fluorouracil-resistant cells, but not the frequency of adriamycin-resistant cells. The magnitude of induction of 5-fluorouracil and methotrexate resistance shows a complex dependence on the radiation dose and on the interval between irradiation and assessment of drug resistance. For a dose of 3 Gy, induced 5-fluorouracil and methotrexate resistance is seen only after an interval of 5 to 7 days, whereas for a dose of 12 Gy, high levels of induced resistance are observed 1 to 3 days after irradiation. The maximum absolute risk for induction of resistance is 4 per 10(4) cells per Gy for methotrexate, and 3 per 10(6) cells per Gy for 5-fluorouracil. These results indicate that tumor hypoxia may play a role in the increased levels of drug resistance seen after irradiation, and that both genetic and environmental factors may influence radiation-induction of drug resistance. These studies provide essential data for models of the development of tumor drug resistance, and imply that some of the drug resistance seen when chemotherapy follows radiotherapy may be caused by radiation-induced drug resistance

  8. Periurethral granular cell tumor: a case report

    International Nuclear Information System (INIS)

    Kim, Jeong Kon; Choi, Hyo Gyeong; Cho, Kyoung Sik

    1998-01-01

    Granular cell tumors are uncommon soft tissue tumors which arise as solitary or multiple masses. Lesions commonly arise in the head, neck, and chest wall, but can occur in any part of the body. To our knowledge, periurethral granular cell tumor has not been previously reported. We report one such case

  9. Influence of docosahexaenoic acid in vitro on intracellular adriamycin concentration in lymphocytes and human adriamycin-sensitive and -resistant small-cell lung cancer cell lines, and on cytotoxicity in the tumor cell lines

    NARCIS (Netherlands)

    Zijlstra, J G; de Vries, E G; Muskiet, F A; Martini, I A; Timmer-Bosscha, H; Mulder, N H

    1987-01-01

    An increase in the therapeutic effects of cancer chemotherapeutic agents and circumvention of drug resistance in cancer cells might result from an increase in the intracellular drug level. Alteration of the lipid domain of the cell membrane can result in a higher intracellular drug level. This

  10. Granular cell tumor: An uncommon benign neoplasm

    Directory of Open Access Journals (Sweden)

    Tirthankar Gayen

    2015-01-01

    Full Text Available Granular cell tumor is a distinctly rare neoplasm of neural sheath origin. It mainly presents as a solitary asymptomatic swelling in the oral cavity, skin, and rarely internal organs in the middle age. Histopathology is characteristic, showing polyhedral cells containing numerous fine eosinophilic granules with indistinct cell margins. We present a case of granular cell tumor on the back of a 48-year-old woman which was painful, mimicking an adnexal tumor.

  11. Molecular mechanisms of bortezomib resistant adenocarcinoma cells.

    Directory of Open Access Journals (Sweden)

    Erika Suzuki

    Full Text Available Bortezomib (Velcade™ is a reversible proteasome inhibitor that is approved for the treatment of multiple myeloma (MM. Despite its demonstrated clinical success, some patients are deprived of treatment due to primary refractoriness or development of resistance during therapy. To investigate the role of the duration of proteasome inhibition in the anti-tumor response of bortezomib, we established clonal isolates of HT-29 adenocarcinoma cells adapted to continuous exposure of bortezomib. These cells were ~30-fold resistant to bortezomib. Two novel and distinct mutations in the β5 subunit, Cys63Phe, located distal to the binding site in a helix critical for drug binding, and Arg24Cys, found in the propeptide region were found in all resistant clones. The latter mutation is a natural variant found to be elevated in frequency in patients with MM. Proteasome activity and levels of both the constitutive and immunoproteasome were increased in resistant cells, which correlated to an increase in subunit gene expression. These changes correlated with a more rapid recovery of proteasome activity following brief exposure to bortezomib. Increased recovery rate was not due to increased proteasome turnover as similar findings were seen in cells co-treated with cycloheximide. When we exposed resistant cells to the irreversible proteasome inhibitor carfilzomib we noted a slower rate of recovery of proteasome activity as compared to bortezomib in both parental and resistant cells. Importantly, carfilzomib maintained its cytotoxic potential in the bortezomib resistant cell lines. Therefore, resistance to bortezomib, can be overcome with irreversible inhibitors, suggesting prolonged proteasome inhibition induces a more potent anti-tumor response.

  12. Cisplatin Resistant Spheroids Model Clinically Relevant Survival Mechanisms in Ovarian Tumors.

    Directory of Open Access Journals (Sweden)

    Winyoo Chowanadisai

    Full Text Available The majority of ovarian tumors eventually recur in a drug resistant form. Using cisplatin sensitive and resistant cell lines assembled into 3D spheroids we profiled gene expression and identified candidate mechanisms and biological pathways associated with cisplatin resistance. OVCAR-8 human ovarian carcinoma cells were exposed to sub-lethal concentrations of cisplatin to create a matched cisplatin-resistant cell line, OVCAR-8R. Genome-wide gene expression profiling of sensitive and resistant ovarian cancer spheroids identified 3,331 significantly differentially expressed probesets coding for 3,139 distinct protein-coding genes (Fc >2, FDR < 0.05 (S2 Table. Despite significant expression changes in some transporters including MDR1, cisplatin resistance was not associated with differences in intracellular cisplatin concentration. Cisplatin resistant cells were significantly enriched for a mesenchymal gene expression signature. OVCAR-8R resistance derived gene sets were significantly more biased to patients with shorter survival. From the most differentially expressed genes, we derived a 17-gene expression signature that identifies ovarian cancer patients with shorter overall survival in three independent datasets. We propose that the use of cisplatin resistant cell lines in 3D spheroid models is a viable approach to gain insight into resistance mechanisms relevant to ovarian tumors in patients. Our data support the emerging concept that ovarian cancers can acquire drug resistance through an epithelial-to-mesenchymal transition.

  13. [Circulating tumor cells: cornerstone of personalized medicine].

    Science.gov (United States)

    Rafii, A; Vidal, F; Rathat, G; Alix-Panabières, C

    2014-11-01

    Cancer treatment has evolved toward personalized medicine. It is mandatory for clinicians to ascertain tumor biological features in order to optimize patients' treatment. Identification and characterization of circulating tumor cells demonstrated a prognostic value in many solid tumors. Here, we describe the main technologies for identification and characterization of circulating tumor cells and their clinical application in gynecologic and breast cancers. Copyright © 2014. Published by Elsevier Masson SAS.

  14. Tumor and Endothelial Cell Hybrids Participate in Glioblastoma Vasculature

    Directory of Open Access Journals (Sweden)

    Soufiane El Hallani

    2014-01-01

    Full Text Available Background. Recently antiangiogenic therapy with bevacizumab has shown a high but transient efficacy in glioblastoma (GBM. Indeed, GBM is one of the most angiogenic human tumors and endothelial proliferation is a hallmark of the disease. We therefore hypothesized that tumor cells may participate in endothelial proliferation of GBM. Materials and Methods. We used EGFR FISH Probe to detect EGFR amplification and anti-CD31, CD105, VE-cadherin, and vWF to identify endothelial cells. Endothelial and GBM cells were grown separately, labeled with GFP and DsRed lentiviruses, and then cocultured with or without contact. Results. In a subset of GBM tissues, we found that several tumor endothelial cells carry EGFR amplification, characteristic of GBM tumor cells. This observation was reproduced in vitro: when tumor stem cells derived from GBM were grown in the presence of human endothelial cells, a fraction of them acquired endothelial markers (CD31, CD105, VE-cadherin, and vWF. By transduction with GFP and DsRed expressing lentiviral vectors, we demonstrate that this phenomenon is due to cell fusion and not transdifferentiation. Conclusion. A fraction of GBM stem cells thus has the capacity to fuse with endothelial cells and the resulting hybrids may participate in tumor microvascular proliferation and in treatment resistance.

  15. Progress toward overcoming hypoxia-induced resistance to solid tumor therapy

    International Nuclear Information System (INIS)

    Karakashev, Sergey V; Reginato, Mauricio J

    2015-01-01

    Hypoxic tumors are associated with poor clinical outcome for multiple types of human cancer. This may be due, in part, to hypoxic cancer cells being resistant to anticancer therapy, including radiation therapy, chemotherapy, and targeted therapy. Hypoxia inducible factor 1, a major regulator of cellular response to hypoxia, regulates the expression of genes that are involved in multiple aspects of cancer biology, including cell survival, proliferation, metabolism, invasion, and angiogenesis. Here, we review multiple pathways regulated by hypoxia/hypoxia inducible factor 1 in cancer cells and discuss the latest advancements in overcoming hypoxia-mediated tumor resistance

  16. The influence of the stem cell marker ALDH and the EGFR-PI3 kinase act signaling pathway on the radiation resistance of human tumor cell lines; Der Einfluss des Stammzellmarkers ALDH und des EGFR-PI3 Kinase-Akt Signalwegs auf die Strahlenresistenz humaner Tumorzelllinien

    Energy Technology Data Exchange (ETDEWEB)

    Mihatsch, Julia

    2014-07-14

    Cancer is the second leading cause of death in industriated nations. Besides surgery and chemotherapy, radiotherapy (RT) is an important approach by which about 60% of patients are treated. The response of these patients to RT is very heterogenous. On the one hand, there are patients with tumors which are radiosensitive and can be cured, but on the other hand patients bear tumors which are quite resistant to radiotherapy. A Radioresistant phenotype of tumor cells causes treatment failure consequently leading to a limited response to radiotherapy. It is proposed, that radiotherapy outcome mainly depends on the potential of radiation on controlling growth, proliferation and survival of a specific population of tumor cells called cancer stem cells (CSCs) or tumor-initiating cells. Based on experimental studies so far reported it is assumed that the population of CSC varies in tumors from different entities and is relatively low compared to the tumor bulk cells in general. According to the CSC hypothesis, it might be concluded that the differential response of tumors to radiotherapy depends on CSC populations, since these supposedly slow replicating cells are able to initiate a tumor, to self renew indefinitely and to generate the differentiated progeny of a tumor. Besides the role of cancer stem cells in radiotherapy response, ionizing radiation (IR) activates the epidermal growth factor receptor (EGFR) and its downstream signaling pathways such as phosphoinositide 3-kinase (PI3K)/Akt, mitogen-activated protein kinase (MAPK) and Janus kinase/Signal Transducer and Activator of Transcription (JAK/STAT) pathways. Among these pathways, PI3K/Akt is one of the most important pathways involved in post-irradiation survival: Activation of Akt results in activation of DNA-dependent protein kinase, catalytic subunit (DNA-PKcs). DNA-PKcs is a core enzyme involved in repair of IR-induced DNA-double strand breaks (DNA-DSB) through non-homologous end joining (NHEJ). The aim of the

  17. Cancer Stem Cell Plasticity Drives Therapeutic Resistance

    Directory of Open Access Journals (Sweden)

    Mary R. Doherty

    2016-01-01

    Full Text Available The connection between epithelial-mesenchymal (E-M plasticity and cancer stem cell (CSC properties has been paradigm-shifting, linking tumor cell invasion and metastasis with therapeutic recurrence. However, despite their importance, the molecular pathways involved in generating invasive, metastatic, and therapy-resistant CSCs remain poorly understood. The enrichment of cells with a mesenchymal/CSC phenotype following therapy has been interpreted in two different ways. The original interpretation posited that therapy kills non-CSCs while sparing pre-existing CSCs. However, evidence is emerging that suggests non-CSCs can be induced into a transient, drug-tolerant, CSC-like state by chemotherapy. The ability to transition between distinct cell states may be as critical for the survival of tumor cells following therapy as it is for metastatic progression. Therefore, inhibition of the pathways that promote E-M and CSC plasticity may suppress tumor recurrence following chemotherapy. Here, we review the emerging appreciation for how plasticity confers therapeutic resistance and tumor recurrence.

  18. Cell structure and proliferative activity of organ cultures of normal embryonic lung tissue of mice resistant (C57BL) and predisposed (A) to lung tumors

    International Nuclear Information System (INIS)

    Kolesnichenko, T.S.; Gor'kova, T.G.

    1985-01-01

    Local factors such as proliferative activity and the numerical ratio between epithelial and mesenchymal cells, and also the character of interaction between the tissue components in ontogeny may play an important role in the realization of sensitivity of mice of a particular line to the development of lung tumors. These characteristics of lung tissue in mice of lines A and C57BL are investigated under normal conditions and during induced carcinogenesis. Results are given of a comparative study of the relative numbers of epithelial and mesenchymal cells in organ cultures of embryonic lungs. 3 H-thymidine was added to the cultures on the 14th day of the experiment in a concentration of 1 microCi/m1 medium. An autoradiographic study of the cultures was performed

  19. Role of Axumin PET Scan in Germ Cell Tumor

    Science.gov (United States)

    2018-05-01

    Testis Cancer; Germ Cell Tumor; Testicular Cancer; Germ Cell Tumor of Testis; Germ Cell Tumor, Testicular, Childhood; Testicular Neoplasms; Testicular Germ Cell Tumor; Testicular Yolk Sac Tumor; Testicular Choriocarcinoma; Testicular Diseases; Germ Cell Cancer Metastatic; Germ Cell Neoplasm of Retroperitoneum; Germ Cell Cancer, Nos

  20. Stages of Childhood Extracranial Germ Cell Tumors

    Science.gov (United States)

    ... tumors: Yolk sac tumors make a hormone called alpha-fetoprotein (AFP). They can form in the ovary, testicle, ... are used to detect extracranial germ cell tumors: Alpha-fetoprotein (AFP). Beta-human chorionic gonadotropin (β-hCG). For ...

  1. Intracranial germ-cell tumors

    International Nuclear Information System (INIS)

    Baker, L.L.; Kollias, S.S.; Cogen, P.H.; Barkovich, A.J.

    1991-01-01

    This paper reports on the MR characteristics together with the clinical and histologic features of cerebral germ-cell tumors were investigated to augment data regarding this rare, diverse class of neoplasms. Germinomas were homogeneous or heterogeneous masses, predominantly isointense to normal brain on T1-weighted images, and hyperintense and heterogeneous on T2-weighted images; three showed adjacent brain edema. Enhancement was prominent, either homogeneous or heterogeneous. One had spinal drop metastases. Teratomas, more common in young patients, were more heterogeneous than germinomas on T1-weighted and T2-weighted images. Five showed hyper- and hypointense foci on T1-weighted images that corresponded to fat and calcium, respectively, at CT. Teratomas did not enhance or enhanced heterogeneously. Two had intratumoral hemorrhage; there were no metastases. Both patients with choriocarcinoma had hemorrhagic masses

  2. Mechanisms of drug resistance in cancer cells

    International Nuclear Information System (INIS)

    Iqbal, M.P.

    2003-01-01

    Development of drug resist chemotherapy. For the past several years, investigators have been striving hard to unravel mechanisms of drug resistance in cancer cells. Using different experimental models of cancer, some of the major mechanisms of drug resistance identified in mammalian cells include: (a) Altered transport of the drug (decreased influx of the drug; increased efflux of the drug (role of P-glycoprotein; role of polyglutamation; role of multiple drug resistance associated protein)), (b) Increase in total amount of target enzyme/protein (gene amplification), (c) alteration in the target enzyme/protein (low affinity enzyme), (d) Elevation of cellular glutathione, (e) Inhibition of drug-induced apoptosis (mutation in p53 tumor suppressor gene; increased expression of bcl-xl gene). (author)

  3. The lifetime of hypoxic human tumor cells

    International Nuclear Information System (INIS)

    Durand, Ralph E.; Sham, Edward

    1998-01-01

    Purpose: For hypoxic and anoxic cells in solid tumors to be a therapeutic problem, they must live long enough to be therapeutically relevant, or else be rapidly recruited into the proliferating compartment during therapy. We have, therefore, estimated lifetime and recruitment rate of hypoxic human tumor cells in multicell spheroids in vitro, or in xenografted tumors in SCID mice. Materials and Methods: Cell turnover was followed by flow cytometry techniques, using antibodies directed at incorporated halogenated pyrimidines. The disappearance of labeled cells was quantified, and verified to be cell loss rather than label dilution. Repopulation was studied in SiHa tumor xenografts during twice-daily 2.5-Gy radiation exposures. Results: The longevity of hypoxic human tumor cells in spheroids or xenografts exceeded that of rodent cell lines, and cell turnover was slower in xenografts than under static growth as spheroids. Human tumor cells remained viable in the hypoxic regions of xenografts for 4-10 days, compared to 3-5 days in spheroids, and 1-3 days for most rodent cells in spheroids. Repopulation was observed within the first few radiation treatments for the SiHa xenografts and, with accumulated doses of more than 10 Gy, virtually all recovered cells had progressed through at least one S-phase. Conclusion: Our results suggest an important difference in the ability of human vs. rodent tumor cells to withstand hypoxia, and raise questions concerning the increased longevity seen in vivo relative to the steady-state spheroid system

  4. Molecular aspects of tumor cell migration and invasion

    Directory of Open Access Journals (Sweden)

    Giuseppina Bozzuto

    2010-03-01

    Full Text Available Cell migration and invasion are crucial steps in many physiological events. However, they are also implicated in the physiopathology of many diseases, such as cancer. To spread through the tissues, tumor cells use mechanisms that involve several molecular actors: adhesion receptor families, receptor tyrosine kinases, cytoskeleton proteins, adapter and signalling proteins interplay in a complex scenario. The balance of cellular signals for proliferation and survival responses also regulates migratory behaviours of tumor cells. To complicate the scene of crime drug resistance players can interfere thus worsening this delicate situation. The complete understanding of this molecular jungle is an impossible mission: some molecular aspects are reviewed in this paper.

  5. HAMLET interacts with histones and chromatin in tumor cell nuclei.

    Science.gov (United States)

    Düringer, Caroline; Hamiche, Ali; Gustafsson, Lotta; Kimura, Hiroshi; Svanborg, Catharina

    2003-10-24

    HAMLET is a folding variant of human alpha-lactalbumin in an active complex with oleic acid. HAMLET selectively enters tumor cells, accumulates in their nuclei and induces apoptosis-like cell death. This study examined the interactions of HAMLET with nuclear constituents and identified histones as targets. HAMLET was found to bind histone H3 strongly and to lesser extent histones H4 and H2B. The specificity of these interactions was confirmed using BIAcore technology and chromatin assembly assays. In vivo in tumor cells, HAMLET co-localized with histones and perturbed the chromatin structure; HAMLET was found associated with chromatin in an insoluble nuclear fraction resistant to salt extraction. In vitro, HAMLET bound strongly to histones and impaired their deposition on DNA. We conclude that HAMLET interacts with histones and chromatin in tumor cell nuclei and propose that this interaction locks the cells into the death pathway by irreversibly disrupting chromatin organization.

  6. Treatment Option Overview (Ovarian Germ Cell Tumors)

    Science.gov (United States)

    ... Germ Cell Tumors Treatment (PDQ®)–Patient Version Treatment Option Overview Go to Health Professional Version Key Points ... and restore) the body’s blood cells. New treatment options Combination chemotherapy (the use of more than one ...

  7. Treatment Option Overview (Extragonadal Germ Cell Tumors)

    Science.gov (United States)

    ... Cell Tumors Treatment Testicular Cancer Treatment Age and gender can affect the risk of extragonadal germ cell ... Headache. Change in bowel habits. Feeling very tired. Trouble walking. Trouble in seeing or moving the eyes. ...

  8. General Information about Extragonadal Germ Cell Tumors

    Science.gov (United States)

    ... Cell Tumors Treatment Testicular Cancer Treatment Age and gender can affect the risk of extragonadal germ cell ... Headache. Change in bowel habits. Feeling very tired. Trouble walking. Trouble in seeing or moving the eyes. ...

  9. Immune Cells in Blood Recognize Tumors

    Science.gov (United States)

    NCI scientists have developed a novel strategy for identifying immune cells circulating in the blood that recognize specific proteins on tumor cells, a finding they believe may have potential implications for immune-based therapies.

  10. CD133 expression in chemo-resistant Ewing sarcoma cells

    Directory of Open Access Journals (Sweden)

    Kovar Heinrich

    2010-03-01

    Full Text Available Abstract Background Some human cancers demonstrate cellular hierarchies in which tumor-initiating cancer stem cells generate progeny cells with reduced tumorigenic potential. This cancer stem cell population is proposed to be a source of therapy-resistant and recurrent disease. Ewing sarcoma family tumors (ESFT are highly aggressive cancers in which drug-resistant, relapsed disease remains a significant clinical problem. Recently, the cell surface protein CD133 was identified as a putative marker of tumor-initiating cells in ESFT. We evaluated ESFT tumors and cell lines to determine if high levels of CD133 are associated with drug resistance. Methods Expression of the CD133-encoding PROM1 gene was determined by RT-PCR in ESFT tumors and cell lines. CD133 protein expression was assessed by western blot, FACS and/or immunostaining. Cell lines were FACS-sorted into CD133+ and CD133- fractions and proliferation, colony formation in soft agar, and in vivo tumorigenicity compared. Chemosensitivity was measured using MTS (3-(4,5-dimethylthiazol-2-yl-5-(3-carboxy-methoxyphenyl-2-(4-sulfophenyl-2H-tetrazolium assays. Results PROM1 expression was either absent or extremely low in most tumors. However, PROM1 was highly over-expressed in 4 of 48 cases. Two of the 4 patients with PROM1 over-expressing tumors rapidly succumbed to primary drug-resistant disease and two are long-term, event-free survivors. The expression of PROM1 in ESFT cell lines was similarly heterogeneous. The frequency of CD133+ cells ranged from 2-99% and, with one exception, no differences in the chemoresistance or tumorigenicity of CD133+ and CD133- cell fractions were detected. Importantly, however, the STA-ET-8.2 cell line was found to retain a cellular hierarchy in which relatively chemo-resistant, tumorigenic CD133+ cells gave rise to relatively chemo-sensitive, less tumorigenic, CD133- progeny. Conclusions Up to 10% of ESFT express high levels of PROM1. In some tumors and cell

  11. Pathway-specific differences between tumor cell lines and normal and tumor tissue cells

    Directory of Open Access Journals (Sweden)

    Tozeren Aydin

    2006-11-01

    Full Text Available Abstract Background Cell lines are used in experimental investigation of cancer but their capacity to represent tumor cells has yet to be quantified. The aim of the study was to identify significant alterations in pathway usage in cell lines in comparison with normal and tumor tissue. Methods This study utilized a pathway-specific enrichment analysis of publicly accessible microarray data and quantified the gene expression differences between cell lines, tumor, and normal tissue cells for six different tissue types. KEGG pathways that are significantly different between cell lines and tumors, cell lines and normal tissues and tumor and normal tissue were identified through enrichment tests on gene lists obtained using Significance Analysis of Microarrays (SAM. Results Cellular pathways that were significantly upregulated in cell lines compared to tumor cells and normal cells of the same tissue type included ATP synthesis, cell communication, cell cycle, oxidative phosphorylation, purine, pyrimidine and pyruvate metabolism, and proteasome. Results on metabolic pathways suggested an increase in the velocity nucleotide metabolism and RNA production. Pathways that were downregulated in cell lines compared to tumor and normal tissue included cell communication, cell adhesion molecules (CAMs, and ECM-receptor interaction. Only a fraction of the significantly altered genes in tumor-to-normal comparison had similar expressions in cancer cell lines and tumor cells. These genes were tissue-specific and were distributed sparsely among multiple pathways. Conclusion Significantly altered genes in tumors compared to normal tissue were largely tissue specific. Among these genes downregulation was a major trend. In contrast, cell lines contained large sets of significantly upregulated genes that were common to multiple tissue types. Pathway upregulation in cell lines was most pronounced over metabolic pathways including cell nucleotide metabolism and oxidative

  12. Enrichment of tumor cells for cell kinetic analysis in human tumor biopsies using cytokeratin gating

    International Nuclear Information System (INIS)

    Haustermans, K.; Hofland, I.; Ramaekers, M.; Ivanyi, D.; Balm, A.J.M.; Geboes, K.; Lerut, T.; Schueren, E. van der; Begg, A.C.

    1996-01-01

    Purpose: To determine the feasibility of using cytokeratin antibodies to distinguish normal and malignant cells in human tumors using flow cytometry. The goal was ultimately to increase the accuracy of cell kinetic measurements on human tumor biopsies. Material and methods: A panel of four antibodies was screened on a series of 48 tumors from two centres; 22 head and neck tumors (Amsterdam) and 26 esophagus carcinomas (Leuven). First, screening was carried out by immunohistochemistry on frozen sections to test intensity of staining and the fraction of cytokeratin-positive tumor cells. The antibody showing the most positive staining was then used for flow cytometry on the same tumor. Results: The two broadest spectrum antibodies (AE1/AE3, E3/C4) showed overall the best results with immunohistochemical staining, being positive in over 95% of tumors. Good cell suspensions for DNA flow cytometry could be made from frozen material by a mechanical method, whereas enzymatic methods with trypsin or collagenase were judged failures in almost all cases. >From fresh material, both collagenase and trypsin produced good suspensions for flow cytometry, although the fraction of tumor cells, judged by proportion aneuploid cells, was markedly higher for trypsin. Using the best cytokeratin antibody for each tumor, two parameter flow cytometry was done (cytokeratin versus DNA content). Enrichment of tumor cells was then tested by measuring the fraction of aneuploid cells (the presumed malignant population) of cytokeratin-positive cells versus all cells. An enrichment factor ranging between 0 (no enrichment) and 1 (perfect enrichment, tumor cells only) was then calculated. The average enrichment was 0.60 for head and neck tumors and 0.59 for esophagus tumors. Conclusions: We conclude that this method can substantially enrich the proportion of tumor cells in biopsies from carcinomas. Application of this method could significantly enhance accuracy of tumor cell kinetic measurements

  13. Glioma Cells in the Tumor Periphery Have a Stem Cell Phenotype

    DEFF Research Database (Denmark)

    Munthe, Sune; Petterson, Stine Asferg; Dahlrot, Rikke Hedegaard

    2016-01-01

    and a panel of markers was used. The panel comprised of six stem cell-related markers (CD133, Musashi-1, Bmi-1, Sox-2, Nestin and Glut-3), a proliferation marker (Ki-67) as well as a chemo-resistance marker (MGMT). Computer-based automated classifiers were designed to measure the mIDH1 positive nucleus area......-fraction of the chosen markers. Moreover, orthotopic glioblastoma xenografts from five different patient-derived spheroid cultures were obtained and the tumor cells identified by human specific immunohistochemical markers. The results showed that tumor cells in the periphery of patient gliomas expressed stem cell...... in the periphery of patient gliomas have a stem cell phenotype, although it is less pronounced than in the tumor core. Novel therapies aiming at preventing recurrence should therefore take tumor stemness into account. Migrating cells in orthotopic glioblastoma xenografts preserve expression and stem cell markers...

  14. HPMA copolymer-bound doxorubicin induces immunogenic tumor cell death.

    Science.gov (United States)

    Sirova, M; Kabesova, M; Kovar, L; Etrych, T; Strohalm, J; Ulbrich, K; Rihova, B

    2013-01-01

    Treatment of murine EL4 T cell lymphoma with N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer conjugates of doxorubicin (Dox) leads to complete tumor regression and to the development of therapy-dependent longlasting cancer resistance. This phenomenon occurs with two types of Dox conjugates tested, despite differences in the covalent linkage of Dox to the polymer carrier. Such a cancer resistance cannot fully express in conventional treatment with free Dox, due to substantial immunotoxicity of the treatment, which was not observed in the polymer conjugates. In this study, calreticulin (CRT) translocation and high mobility group box-1 protein (HMGB1) release was observed in EL4 cells treated with a conjugate releasing Dox by a pH-dependent manner. As a result, the treated tumor cells were engulfed by dendritic cells (DC) in vitro, and induced their expression of CD80, CD86, and MHC II maturation markers. Conjugates with Dox bound via an amide bond only increased translocation of HSPs to the membrane, which led to an elevated phagocytosis but was not sufficient to induce increase of the maturation markers on DCs in vitro. Both types of conjugates induced engulfment of the target tumor cells in vivo, that was more intense than that seen with free Dox. It means that the induction of anti-tumor immunity documented upon treatment of EL4 lymphoma with HPMA-bound Dox conjugates does not rely solely on CRT-mediated cell death, but involves multiple mechanisms.

  15. Transformation Resistance in a Premature Aging Disorder Identifies a Tumor-Protective Function of BRD4

    Directory of Open Access Journals (Sweden)

    Patricia Fernandez

    2014-10-01

    Full Text Available Summary: Advanced age and DNA damage accumulation are prominent risk factors for cancer. The premature aging disorder Hutchinson-Gilford progeria syndrome (HGPS provides a unique opportunity for studying the interplay between DNA damage and aging-associated tumor mechanisms, given that HGPS patients do not develop tumors despite elevated levels of DNA damage. Here, we have used HGPS patient cells to identify a protective mechanism to oncogenesis. We find that HGPS cells are resistant to neoplastic transformation. Resistance is mediated by the bromodomain protein BRD4, which exhibits altered genome-wide binding patterns in transformation-resistant cells, leading to inhibition of oncogenic dedifferentiation. BRD4 also inhibits, albeit to a lower extent, the tumorigenic potential of transformed cells from healthy individuals. BRD4-mediated tumor protection is clinically relevant given that a BRD4 gene signature predicts positive clinical outcome in breast and lung cancer. Our results demonstrate a protective function for BRD4 and suggest tissue-specific roles for BRD4 in tumorigenesis. : The premature aging disorder Hutchinson-Gilford progeria syndrome (HGPS provides a unique tool for studying the interplay between DNA damage and aging-associated tumor mechanisms, given that HGPS patients do not develop tumors despite elevated levels of DNA damage. Using a genome-wide RNAi screen, Fernandez et al. now identify the bromodomain protein BRD4 as a mediator of the oncogenic resistance of HGPS cells. This tumor-protective function of BRD4 involves inhibition of oncogenic dedifferentiation and is also active in non-HGPS cells in a tissue-specific manner.

  16. Harnessing Dendritic Cells for Tumor Antigen Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Nierkens, Stefan [Department of Tumor Immunology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Geert Grooteplein 28, Nijmegen 6525 GA (Netherlands); Janssen, Edith M., E-mail: edith.janssen@cchmc.org [Division of Molecular Immunology, Cincinnati Children' s Hospital Research Foundation, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229 (United States)

    2011-04-26

    Dendritic cells (DC) are professional antigen presenting cells that are crucial for the induction of anti-tumor T cell responses. As a consequence, research has focused on the harnessing of DCs for therapeutic interventions. Although current strategies employing ex vivo-generated and tumor-antigen loaded DCs have been proven feasible, there are still many obstacles to overcome in order to improve clinical trial successes and offset the cost and complexity of customized cell therapy. This review focuses on one of these obstacles and a pivotal step for the priming of tumor-specific CD8{sup +} and CD4{sup +} T cells; the in vitro loading of DCs with tumor antigens.

  17. Breast cancer resistance protein is localized at the plasma membrane in mitoxantrone- and topotecan-resistant cell lines

    NARCIS (Netherlands)

    Scheffer, GL; Maliepaard, M; Pijnenborg, ACLM; van Gastelen, MA; Schroeijers, AB; Allen, JD; Ross, DD; van der Valk, P; Dalton, WS; Schellens, JHM; Scheper, RJ; de Jong, MC

    2000-01-01

    Tumor cells may display a multidrug resistant phenotype by overexpression of ATP-binding cassette transporters such as multidrug resistance (,MDR1) P-glycoprotein, multidrug resistance protein 1 (MRP1), and breast cancer resistance protein (BCRP). The presence of BCRP has thus far been reported

  18. Seeing is believing: are cancer stem cells the Loch Ness monster of tumor biology?

    Science.gov (United States)

    Lathia, Justin D; Venere, Monica; Rao, Mahendra S; Rich, Jeremy N

    2011-06-01

    Tumors are complex systems with a diversity of cell phenotypes essential to tumor initiation and maintenance. With the heterogeneity present within the neoplastic compartment as its foundation, the cancer stem cell hypothesis posits that a fraction of tumor cells has the capacity to recapitulate the parental tumor upon transplantation. Over the last decade, the cancer stem cell hypothesis has gained support and shown to be relevant in many highly lethal solid tumors. However, the cancer stem cell hypothesis is not without its controversies and critics question the validity of this hypothesis based upon comparisons to normal somatic stem cells. Cancer stem cells may have direct therapeutic relevance due to resistance to current treatment paradigms, suggesting novel multimodal therapies targeting the cancer stem cells may improve patient outcomes. In this review, we will use the most common primary brain tumor, glioblastoma multiforme, as an example to illustrate why studying cancer stem cells holds great promise for more effective therapies to highly lethal tumors. In addition, we will discuss why the abilities of self-renewal and tumor propagation are the critical defining properties of cancer stem cells. Furthermore, we will examine recent progress in defining appropriate cell surface selection markers and mouse models which explore the potential cell(s) or origin for GBMs. What remains clear is that a population of cells is present in many tumors which are resistant to conventional therapies and must be considered in the design of the next generation of cancer treatments.

  19. CD4 cells can be more efficient at tumor rejection than CD8 cells.

    Science.gov (United States)

    Perez-Diez, Ainhoa; Joncker, Nathalie T; Choi, Kyungho; Chan, William F N; Anderson, Colin C; Lantz, Olivier; Matzinger, Polly

    2007-06-15

    Researchers designing antitumor treatments have long focused on eliciting tumor-specific CD8 cytotoxic T lymphocytes (CTL) because of their potent killing activity and their ability to reject transplanted organs. The resulting treatments, however, have generally been surprisingly poor at inducing complete tumor rejection, both in experimental models and in the clinic. Although a few scattered studies suggested that CD4 T "helper" cells might also serve as antitumor effectors, they have generally been studied mostly for their ability to enhance the activity of CTL. In this mouse study, we compared monoclonal populations of tumor-specific CD4 and CD8 T cells as effectors against several different tumors, and found that CD4 T cells eliminated tumors that were resistant to CD8-mediated rejection, even in cases where the tumors expressed major histocompatibility complex (MHC) class I molecules but not MHC class II. MHC class II expression on host tissues was critical, suggesting that the CD4 T cells act indirectly. Indeed, the CD4 T cells partnered with NK cells to obtain the maximal antitumor effect. These findings suggest that CD4 T cells can be powerful antitumor effector cells that can, in some cases, outperform CD8 T cells, which are the current "gold standard" effector cell in tumor immunotherapy.

  20. Measuring The Contact Resistances Of Photovoltaic Cells

    Science.gov (United States)

    Burger, D. R.

    1985-01-01

    Simple method devised to measure contact resistances of photovoltaic solar cells. Method uses readily available equipment and applicable at any time during life of cell. Enables evaluation of cell contact resistance, contact-end resistance, contact resistivity, sheet resistivity, and sheet resistivity under contact.

  1. Effects of a tumor promoter and an anti-promoter on spontaneous and UV-induced 6-thioguanine-resistant mutations and sister-chromatid exchanges in V79 Chinese hamster cells

    International Nuclear Information System (INIS)

    Fujiwara, Y.; Kano, Y.; Tatsumi, M.; Paul, P.

    1980-01-01

    The effects of a tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) and/or an anti-promoter antipain (protease inhibitor) on spontaneous and ultraviolet-induced sister-chromatid exchanges (SCEs) and 6-thioguanine-resistant (6TGsup(r)) recessive mutations were examined in V79 Chinese hamster cells in culture. TPA and/or antipain neither significantly altered base-line and UV-induced immediate SCE frequencies, nor decreased the level of delayed SCEs which persisted 6-7 days after irradiation. TPA and/or antipain appeared to enhance the recovery of UV-induced 6TGsup(r) colonies at the plateau expression phase despite non-mutagenicity by themselves and unaltered metabolic cooperation. Thus, the results conceivably imply that the 6TGsup(r)-recessive mutation expression, but not fixation, can be modulated at the cell level by TPA and/or antipain. Our results, together with the recent results of Loveday and Latt, may argue against the notion that TPA enhances the antipain-suppressible SCEs as an index of mitotic recombination in relevance with a tumor-promotion mechanism. (orig.)

  2. POSTTREATMENT NEUROBLASTOMA MATURATION TO GANGLIONIC CELL TUMOR

    Directory of Open Access Journals (Sweden)

    M. V. Ryzhova

    2012-01-01

    Full Text Available Tumor cells can differentiate into more mature forms in undifferentiated or poorly differentiated tumors, such as medulloblastomas with increased nodularity, as well as neuroblastomas. The authors describe 2 cases of neuroblastoma maturation into ganglioneuroblastoma 5 months after chemotherapy in a 2-year-old girl and 3 years after radiotherapy in a 16-year-old girl.

  3. Characterization of cell suspensions from solid tumors

    International Nuclear Information System (INIS)

    Pallavicini, M.

    1985-01-01

    The desirable features of cells in suspension will necessarily be dependent upon the use for which the cells were prepared. Adequate cell yield or recovery is defined by the measurement to be performed. Retention of cellular morphology is important for microscopic identification of cell types in a heterogenous cell suspension, and may be used to determine whether the cells in suspension are representative of those in the tumor in situ. Different dispersal protocols may yield cells with different degrees of clonogenicity, as well as altered biochemical features, such as loss of cellular proteins, surface antigens, nucleotide pools, etc. The quality of the cell suspension can be judged by the degree of cell clumping and level of cellular debris, both of which impact on flow cytometric measurements and studies in which the number of cells be known accurately. Finally, if the data measured on the cells in suspension are to be extrapolated to phenomena occurring in the tumor in situ, it is desirable that the cells in suspension are representative of those in the solid tumor in vivo. This report compares characteristics of tumor cell suspensions obtained by different types of selected disaggregation methods. 33 refs., 2 figs., 4 tabs

  4. Cell of Origin and Cancer Stem Cells in Tumor Suppressor Mouse Models of Glioblastoma.

    Science.gov (United States)

    Alcantara Llaguno, Sheila R; Xie, Xuanhua; Parada, Luis F

    2016-01-01

    The cellular origins and the mechanisms of progression, maintenance of tumorigenicity, and therapeutic resistance are central questions in the glioblastoma multiforme (GBM) field. Using tumor suppressor mouse models, our group recently reported two independent populations of adult GBM-initiating central nervous system progenitors. We found different functional and molecular subtypes depending on the tumor-initiating cell lineage, indicating that the cell of origin is a driver of GBM subtype diversity. Using an in vivo model, we also showed that GBM cancer stem cells (CSCs) or glioma stem cells (GSCs) contribute to resistance to chemotherapeutic agents and that genetic ablation of GSCs leads to a delay in tumor progression. These studies are consistent with the cell of origin and CSCs as critical regulators of the pathogenesis of GBM. © 2016 Alcantara Llaguno et al; Published by Cold Spring Harbor Laboratory Press.

  5. Concomitant tumor resistance: the role of tyrosine isomers in the mechanisms of metastases control.

    Science.gov (United States)

    Ruggiero, Raúl A; Bruzzo, Juan; Chiarella, Paula; Bustuoabad, Oscar D; Meiss, Roberto P; Pasqualini, Christiane D

    2012-03-01

    Concomitant tumor resistance (CR) is a phenomenon in which a tumor-bearing host is resistant to the growth of secondary tumor implants and metastasis. Although previous studies indicated that T-cell-dependent processes mediate CR in hosts bearing immunogenic small tumors, manifestations of CR induced by immunogenic and nonimmunogenic large tumors have been associated with an elusive serum factor. In a recently published study, we identified this factor as meta-tyrosine and ortho-tyrosine, 2 isomers of tyrosine that would not be present in normal proteins. In 3 different murine models of cancer that generate CR, both meta- and ortho-tyrosine inhibited tumor growth. Additionally, we showed that both isoforms of tyrosine blocked metastasis in a fourth model that does not generate CR but is sensitive to CR induced by other tumors. Mechanistic studies showed that the antitumor effects of the tyrosine isomers were mediated in part by early inhibition of the MAP/ERK pathway and inactivation of STAT3, potentially driving tumor cells into a state of dormancy in G(0)-phase. Other mechanisms, putatively involving the activation of an intra-S-phase checkpoint, would also inhibit tumor proliferation by accumulating cells in S-phase. By revealing a molecular basis for the classical phenomenon of CR, our findings may stimulate new generalized approaches to limit the development of metastases that arise after resection of primary tumors or after other stressors that may promote the escape of metastases from dormancy, an issue that is of pivotal importance to oncologists and their patients.

  6. Metabolic changes in tumor cells and tumor-associated macrophages: A mutual relationship.

    Science.gov (United States)

    Netea-Maier, Romana T; Smit, Johannes W A; Netea, Mihai G

    2018-01-28

    In order to adapt to the reduced availability of nutrients and oxygen in the tumor microenvironment and the increased requirements of energy and building blocks necessary for maintaining their high proliferation rate, malignant cells undergo metabolic changes that result in an increased production of lactate, nitric oxide, reactive oxygen species, prostaglandins and other byproducts of arachidonic acid metabolism that influence both the composition of the inflammatory microenvironment and the function of the tumor-associated macrophages (TAMs). In response to cues present in the TME, among which products of altered tumor cell metabolism, TAMs are also required to reprogram their metabolism, with activation of glycolysis, fatty acid synthesis and altered nitrogen cycle metabolism. These changes result in functional reprogramming of TAMs which includes changes in the production of cytokines and angiogenetic factors, and contribute to the tumor progression and metastasis. Understanding the metabolic changes governing the intricate relationship between the tumor cells and the TAMs represents an essential step towards developing novel therapeutic approaches targeting the metabolic reprogramming of the immune cells to potentiate their tumoricidal potential and to circumvent therapy resistance. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Tumor cell-derived microparticles polarize M2 tumor-associated macrophages for tumor progression.

    Science.gov (United States)

    Ma, Ruihua; Ji, Tiantian; Chen, Degao; Dong, Wenqian; Zhang, Huafeng; Yin, Xiaonan; Ma, Jingwei; Liang, Xiaoyu; Zhang, Yi; Shen, Guanxin; Qin, Xiaofeng; Huang, Bo

    2016-04-01

    Despite identification of macrophages in tumors (tumor-associated macrophages, TAM) as potential targets for cancer therapy, the origin and function of TAM in the context of malignancy remain poorly characterized. Here, we show that microparticles (MPs), as a by-product, released by tumor cells act as a general mechanism to mediate M2 polarization of TAM. Taking up tumor MPs by macrophages is a very efficient process, which in turn results in the polarization of macrophages into M2 type, not only leading to promoting tumor growth and metastasis but also facilitating cancer stem cell development. Moreover, we demonstrate that the underlying mechanism involves the activation of the cGAS/STING/TBK1/STAT6 pathway by tumor MPs. Finally, in addition to murine tumor MPs, we show that human counterparts also possess consistent effect on human M2 polarization. These findings provide new insights into a critical role of tumor MPs in remodeling of tumor microenvironment and better understanding of the communications between tumors and macrophages.

  8. Radiation Therapy of Suprasellar Germ Cell Tumors

    International Nuclear Information System (INIS)

    Park, Woo Yoon; Choi, Doo Ho; Choi, Eun Kyung; Kim, Il Han; Ha, Sung Whan; Park, Charn Il

    1988-01-01

    A retrospective study was performed on 15 patients with suprasellar germ cell tumors treated by megavoltage external beam irradiation between Feb. 1979 and Dec. 1985. Follow-up period of survivors was 30 to 91 months. Histologic diagnosis was obtained before radiation therapy in 10 patients (9 germinomas and 1 mixed). Five patients were treated without histologic verification. In 9 patients with biopsy-proven germinomas radiation therapy was delivered to the craniospinal axis in 6, to the whole brain in 3. In 5 patients with mixed germ cell tumor or elevated tumor marker, irradiation was delivered to the craniospinal axis in 2, to the whole brain in 2, and to the primary site only in 1. Total doses ranged from 5,000 to 5,500 cGy to the primary site, 3,000 to 4,400 cGy to the whole brain, and 1,300 to 3,000 cGy to the spine. In these 14, local tumor was controlled and primary or spinal failure was not observed. One patient without elevated tumor marker was treated to the whole brain, The tumor was not controlled and he had spinal recurrence. It is proven that radiation therapy is an effective treatment for suprasellar germ cell tumors. The neuroendocrinologic presentation, tumor marker status, early response to radiation measured on CT seem to be useful means for selecting patients for radiation therapy when tissue diagnosis is not available

  9. Cross-resistance to radiation in human squamous cell carcinoma cells with induced cisplatin resistance

    International Nuclear Information System (INIS)

    Komori, Keiichi

    1998-01-01

    Accumulated evidence indicates that drug resistance is induced in tumor cells treated with a variety of anti-cancer drugs and that there is a possibility of cross-resistance to ionizing radiation associated with induced drug resistance. Most in vitro studies have shown inconsistent results on cross-resistance probably because of different cell lines used and protocols for drug induction. In this study, TE3 human squamous cell carcinoma cell line was treated with a 4-day cycle of cisplatin (cis-diamminedichloroplatinum (II); CDDP) at a concentration yielding 10% cell survival. The treatment was repeated up to 3 cycles. After treatment, cells were tested for CDDP and X-ray sensitivity. One cycle of CDDP treatment induced CDDP resistance with a factor of 1.41 and 2 cycles of the treatment with a factor of 1.86. The resistance factor reached a plateau at 3 cycles of treatment. For analyzing the correlation of CDDP and X-ray resistance, 30 clones from both untreated and 3-cycle treated cells were isolated and analyzed for CDDP and X-ray sensitivity. The sensitivity was expressed as the concentration of drug or dose of X-ray required to reduce the cell survival to x% (Dx). The correlation coefficient of clones with 3-cycle treatment between CDDP and X-ray sensitivity increased gradually by increasing the end point of Dx from D 10 to D 90 , resulting in significant correlation at D 90 . The result suggested that there is a certain common repair-related mechanism affecting both CDDP and X-ray resistance in CDDP-treated cells. (author)

  10. MHC-I modulation due to changes in tumor cell metabolism regulates tumor sensitivity to CTL and NK cells

    Science.gov (United States)

    Catalán, Elena; Charni, Seyma; Jaime, Paula; Aguiló, Juan Ignacio; Enríquez, José Antonio; Naval, Javier; Pardo, Julián; Villalba, Martín; Anel, Alberto

    2015-01-01

    Tumor cells have a tendency to use glucose fermentation to obtain energy instead of mitochondrial oxidative phosphorylation (OXPHOS). We demonstrated that this phenotype correlated with loss of ERK5 expression and with reduced MHC class I expression. Consequently, tumor cells could evade cytotoxic T lymphocyte (CTL)-mediated immune surveillance, but also increase their sensitivity to natural killer (NK) cells. These outcomes were evaluated using two cellular models: leukemic EL4 cells and L929 transformed fibroblasts and their derived ρ° cell lines, which lack mitochondrial DNA. We have also used a L929 cell sub-line that spontaneously lost matrix attachment (L929dt), reminiscent of metastasis generation, that also downregulated MHC-I and ERK5 expression. MHC-I expression is lower in ρ° cells than in the parental cell lines, but they were equally sensitive to CTL. On the contrary, ρ° cells were more sensitive to activated NK cells than parental cells. On the other hand, L929dt cells were resistant to CTL and NK cells, showed reduced viability when forced to perform OXPHOS, and surviving cells increased MHC-I expression and became sensitive to CTL. The present results suggest that when the reduction in MHC-I levels in tumor cells due to glycolytic metabolism is partial, the increase in sensitivity to NK cells seems to predominate. However, when tumor cells completely lose MHC-I expression, the combination of treatments that increase OXPHOS with CTL-mediated immunotherapy could be a promising therapeutic approach. PMID:25949869

  11. MHC-I modulation due to changes in tumor cell metabolism regulates tumor sensitivity to CTL and NK cells.

    Science.gov (United States)

    Catalán, Elena; Charni, Seyma; Jaime, Paula; Aguiló, Juan Ignacio; Enríquez, José Antonio; Naval, Javier; Pardo, Julián; Villalba, Martín; Anel, Alberto

    2015-01-01

    Tumor cells have a tendency to use glucose fermentation to obtain energy instead of mitochondrial oxidative phosphorylation (OXPHOS). We demonstrated that this phenotype correlated with loss of ERK5 expression and with reduced MHC class I expression. Consequently, tumor cells could evade cytotoxic T lymphocyte (CTL)-mediated immune surveillance, but also increase their sensitivity to natural killer (NK) cells. These outcomes were evaluated using two cellular models: leukemic EL4 cells and L929 transformed fibroblasts and their derived ρ° cell lines, which lack mitochondrial DNA. We have also used a L929 cell sub-line that spontaneously lost matrix attachment (L929dt), reminiscent of metastasis generation, that also downregulated MHC-I and ERK5 expression. MHC-I expression is lower in ρ° cells than in the parental cell lines, but they were equally sensitive to CTL. On the contrary, ρ° cells were more sensitive to activated NK cells than parental cells. On the other hand, L929dt cells were resistant to CTL and NK cells, showed reduced viability when forced to perform OXPHOS, and surviving cells increased MHC-I expression and became sensitive to CTL. The present results suggest that when the reduction in MHC-I levels in tumor cells due to glycolytic metabolism is partial, the increase in sensitivity to NK cells seems to predominate. However, when tumor cells completely lose MHC-I expression, the combination of treatments that increase OXPHOS with CTL-mediated immunotherapy could be a promising therapeutic approach.

  12. Overcoming Multidrug Resistance in Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Karobi Moitra

    2015-01-01

    Full Text Available The principle mechanism of protection of stem cells is through the expression of ATP-binding cassette (ABC transporters. These transporters serve as the guardians of the stem cell population in the body. Unfortunately these very same ABC efflux pumps afford protection to cancer stem cells in tumors, shielding them from the adverse effects of chemotherapy. A number of strategies to circumvent the function of these transporters in cancer stem cells are currently under investigation. These strategies include the development of competitive and allosteric modulators, nanoparticle mediated delivery of inhibitors, targeted transcriptional regulation of ABC transporters, miRNA mediated inhibition, and targeting of signaling pathways that modulate ABC transporters. The role of ABC transporters in cancer stem cells will be explored in this paper and strategies aimed at overcoming drug resistance caused by these particular transporters will also be discussed.

  13. Epigenetic Modifications and Head and Neck Cancer: Implications for Tumor Progression and Resistance to Therapy

    Directory of Open Access Journals (Sweden)

    Rogerio M. Castilho

    2017-07-01

    Full Text Available Head and neck squamous carcinoma (HNSCC is the sixth most prevalent cancer and one of the most aggressive malignancies worldwide. Despite continuous efforts to identify molecular markers for early detection, and to develop efficient treatments, the overall survival and prognosis of HNSCC patients remain poor. Accumulated scientific evidences suggest that epigenetic alterations, including DNA methylation, histone covalent modifications, chromatin remodeling and non-coding RNAs, are frequently involved in oral carcinogenesis, tumor progression, and resistance to therapy. Epigenetic alterations occur in an unsystematic manner or as part of the aberrant transcriptional machinery, which promotes selective advantage to the tumor cells. Epigenetic modifications also contribute to cellular plasticity during tumor progression and to the formation of cancer stem cells (CSCs, a small subset of tumor cells with self-renewal ability. CSCs are involved in the development of intrinsic or acquired therapy resistance, and tumor recurrences or relapse. Therefore, the understanding and characterization of epigenetic modifications associated with head and neck carcinogenesis, and the prospective identification of epigenetic markers associated with CSCs, hold the promise for novel therapeutic strategies to fight tumors. In this review, we focus on the current knowledge on epigenetic modifications observed in HNSCC and emerging Epi-drugs capable of sensitizing HNSCC to therapy.

  14. Energy and Redox Homeostasis in Tumor Cells

    Directory of Open Access Journals (Sweden)

    Marcus Fernandes de Oliveira

    2012-01-01

    Full Text Available Cancer cells display abnormal morphology, chromosomes, and metabolism. This review will focus on the metabolism of tumor cells integrating the available data by way of a functional approach. The first part contains a comprehensive introduction to bioenergetics, mitochondria, and the mechanisms of production and degradation of reactive oxygen species. This will be followed by a discussion on the oxidative metabolism of tumor cells including the morphology, biogenesis, and networking of mitochondria. Tumor cells overexpress proteins that favor fission, such as GTPase dynamin-related protein 1 (Drp1. The interplay between proapoptotic members of the Bcl-2 family that promotes Drp 1-dependent mitochondrial fragmentation and fusogenic antiapoptotic proteins such as Opa-1 will be presented. It will be argued that contrary to the widespread belief that in cancer cells, aerobic glycolysis completely replaces oxidative metabolism, a misrepresentation of Warburg’s original results, mitochondria of tumor cells are fully viable and functional. Cancer cells also carry out oxidative metabolism and generally conform to the orthodox model of ATP production maintaining as well an intact electron transport system. Finally, data will be presented indicating that the key to tumor cell survival in an ROS rich environment depends on the overexpression of antioxidant enzymes and high levels of the nonenzymatic antioxidant scavengers.

  15. Cancer stem cells and drug resistance: the potential of nanomedicine

    Science.gov (United States)

    Vinogradov, Serguei; Wei, Xin

    2012-01-01

    Properties of the small group of cancer cells called tumor-initiating or cancer stem cells (CSCs) involved in drug resistance, metastasis and relapse of cancers can significantly affect tumor therapy. Importantly, tumor drug resistance seems to be closely related to many intrinsic or acquired properties of CSCs, such as quiescence, specific morphology, DNA repair ability and overexpression of antiapoptotic proteins, drug efflux transporters and detoxifying enzymes. The specific microenvironment (niche) and hypoxic stability provide additional protection against anticancer therapy for CSCs. Thus, CSC-focused therapy is destined to form the core of any effective anticancer strategy. Nanomedicine has great potential in the development of CSC-targeting drugs, controlled drug delivery and release, and the design of novel gene-specific drugs and diagnostic modalities. This review is focused on tumor drug resistance-related properties of CSCs and describes current nanomedicine approaches, which could form the basis of novel combination therapies for eliminating metastatic and CSCs. PMID:22471722

  16. Disrupting Hypoxia-Induced Bicarbonate Transport Acidifies Tumor Cells and Suppresses Tumor Growth.

    Science.gov (United States)

    McIntyre, Alan; Hulikova, Alzbeta; Ledaki, Ioanna; Snell, Cameron; Singleton, Dean; Steers, Graham; Seden, Peter; Jones, Dylan; Bridges, Esther; Wigfield, Simon; Li, Ji-Liang; Russell, Angela; Swietach, Pawel; Harris, Adrian L

    2016-07-01

    Tumor hypoxia is associated clinically with therapeutic resistance and poor patient outcomes. One feature of tumor hypoxia is activated expression of carbonic anhydrase IX (CA9), a regulator of pH and tumor growth. In this study, we investigated the hypothesis that impeding the reuptake of bicarbonate produced extracellularly by CA9 could exacerbate the intracellular acidity produced by hypoxic conditions, perhaps compromising cell growth and viability as a result. In 8 of 10 cancer cell lines, we found that hypoxia induced the expression of at least one bicarbonate transporter. The most robust and frequent inductions were of the sodium-driven bicarbonate transporters SLC4A4 and SLC4A9, which rely upon both HIF1α and HIF2α activity for their expression. In cancer cell spheroids, SLC4A4 or SLC4A9 disruption by either genetic or pharmaceutical approaches acidified intracellular pH and reduced cell growth. Furthermore, treatment of spheroids with S0859, a small-molecule inhibitor of sodium-driven bicarbonate transporters, increased apoptosis in the cell lines tested. Finally, RNAi-mediated attenuation of SLC4A9 increased apoptosis in MDA-MB-231 breast cancer spheroids and dramatically reduced growth of MDA-MB-231 breast tumors or U87 gliomas in murine xenografts. Our findings suggest that disrupting pH homeostasis by blocking bicarbonate import might broadly relieve the common resistance of hypoxic tumors to anticancer therapy. Cancer Res; 76(13); 3744-55. ©2016 AACR. ©2016 American Association for Cancer Research.

  17. Monoclonal TCR-redirected tumor cell killing.

    Science.gov (United States)

    Liddy, Nathaniel; Bossi, Giovanna; Adams, Katherine J; Lissina, Anna; Mahon, Tara M; Hassan, Namir J; Gavarret, Jessie; Bianchi, Frayne C; Pumphrey, Nicholas J; Ladell, Kristin; Gostick, Emma; Sewell, Andrew K; Lissin, Nikolai M; Harwood, Naomi E; Molloy, Peter E; Li, Yi; Cameron, Brian J; Sami, Malkit; Baston, Emma E; Todorov, Penio T; Paston, Samantha J; Dennis, Rebecca E; Harper, Jane V; Dunn, Steve M; Ashfield, Rebecca; Johnson, Andy; McGrath, Yvonne; Plesa, Gabriela; June, Carl H; Kalos, Michael; Price, David A; Vuidepot, Annelise; Williams, Daniel D; Sutton, Deborah H; Jakobsen, Bent K

    2012-06-01

    T cell immunity can potentially eradicate malignant cells and lead to clinical remission in a minority of patients with cancer. In the majority of these individuals, however, there is a failure of the specific T cell receptor (TCR)–mediated immune recognition and activation process. Here we describe the engineering and characterization of new reagents termed immune-mobilizing monoclonal TCRs against cancer (ImmTACs). Four such ImmTACs, each comprising a distinct tumor-associated epitope-specific monoclonal TCR with picomolar affinity fused to a humanized cluster of differentiation 3 (CD3)-specific single-chain antibody fragment (scFv), effectively redirected T cells to kill cancer cells expressing extremely low surface epitope densities. Furthermore, these reagents potently suppressed tumor growth in vivo. Thus, ImmTACs overcome immune tolerance to cancer and represent a new approach to tumor immunotherapy.

  18. ADAM12 produced by tumor cells rather than stromal cells accelerates breast tumor progression

    DEFF Research Database (Denmark)

    Frohlich, Camilla; Nehammer, Camilla; Albrechtsen, Reidar

    2011-01-01

    that ADAM12 deficiency reduces breast tumor progression in the PyMT model. However, the catalytic activity of ADAM12 appears to be dispensable for its tumor-promoting effect. Interestingly, we demonstrate that ADAM12 endogenously expressed in tumor-associated stroma in the PyMT model does not influence......Expression of ADAM12 is low in most normal tissues, but is markedly increased in numerous human cancers, including breast carcinomas. We have previously shown that overexpression of ADAM12 accelerates tumor progression in a mouse model of breast cancer (PyMT). In the present study, we found...... hypothesized, however, that the tumor-associated stroma may stimulate ADAM12 expression in tumor cells, based on the fact that TGF-ß1 stimulates ADAM12 expression and is a well-known growth factor released from tumor-associated stroma. TGF-ß1 stimulation of ADAM12-negative Lewis lung tumor cells induced ADAM12...

  19. CD8+ Tumor-Infiltrating T Cells Are Trapped in the Tumor-Dendritic Cell Network

    Directory of Open Access Journals (Sweden)

    Alexandre Boissonnas

    2013-01-01

    Full Text Available Chemotherapy enhances the antitumor adaptive immune T cell response, but the immunosuppressive tumor environment often dominates, resulting in cancer relapse. Antigen-presenting cells such as tumor-associated macrophages (TAMs and tumor dendritic cells (TuDCs are the main protagonists of tumor-infiltrating lymphocyte (TIL immuno-suppression. TAMs have been widely investigated and are associated with poor prognosis, but the immuno-suppressive activity of TuDCs is less well understood. We performed two-photon imaging of the tumor tissue to examine the spatiotemporal interactions between TILs and TuDCs after chemotherapy. In a strongly immuno-suppressive murine tumor model, cyclophosphamide-mediated chemotherapy transiently enhanced the antitumor activity of adoptively transferred ovalbumin-specific CD8+ T cell receptor transgenic T cells (OTI but barely affected TuDC compartment within the tumor. Time lapse imaging of living tumor tissue showed that TuDCs are organized as a mesh with dynamic interconnections. Once infiltrated into the tumor parenchyma, OTI T cells make antigen-specific and long-lasting contacts with TuDCs. Extensive analysis of TIL infiltration on histologic section revealed that after chemotherapy the majority of OTI T cells interact with TuDCs and that infiltration is restricted to TuDC-rich areas. We propose that the TuDC network exerts antigen-dependent unproductive retention that trap T cells and limit their antitumor effectiveness.

  20. Epigenetics, Nervous System Tumors, and Cancer Stem Cells

    International Nuclear Information System (INIS)

    Qureshi, Irfan A.; Mehler, Mark F.

    2011-01-01

    Recent advances have begun to elucidate how epigenetic regulatory mechanisms are responsible for establishing and maintaining cell identity during development and adult life and how the disruption of these processes is, not surprisingly, one of the hallmarks of cancer. In this review, we describe the major epigenetic mechanisms (i.e., DNA methylation, histone and chromatin modification, non-coding RNA deployment, RNA editing, and nuclear reorganization) and discuss the broad spectrum of epigenetic alterations that have been uncovered in pediatric and adult nervous system tumors. We also highlight emerging evidence that suggests epigenetic deregulation is a characteristic feature of so-called cancer stem cells (CSCs), which are thought to be present in a range of nervous system tumors and responsible for tumor maintenance, progression, treatment resistance, and recurrence. We believe that better understanding how epigenetic mechanisms operate in neural cells and identifying the etiologies and consequences of epigenetic deregulation in tumor cells and CSCs, in particular, are likely to promote the development of enhanced molecular diagnostics and more targeted and effective therapeutic agents for treating recalcitrant nervous system tumors

  1. Epigenetics, Nervous System Tumors, and Cancer Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    Qureshi, Irfan A. [Rosyln and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Department of Neurology, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Mehler, Mark F., E-mail: mark.mehler@einstein.yu.edu [Rosyln and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Department of Neurology, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States); Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, New York, NY 10461 (United States)

    2011-09-13

    Recent advances have begun to elucidate how epigenetic regulatory mechanisms are responsible for establishing and maintaining cell identity during development and adult life and how the disruption of these processes is, not surprisingly, one of the hallmarks of cancer. In this review, we describe the major epigenetic mechanisms (i.e., DNA methylation, histone and chromatin modification, non-coding RNA deployment, RNA editing, and nuclear reorganization) and discuss the broad spectrum of epigenetic alterations that have been uncovered in pediatric and adult nervous system tumors. We also highlight emerging evidence that suggests epigenetic deregulation is a characteristic feature of so-called cancer stem cells (CSCs), which are thought to be present in a range of nervous system tumors and responsible for tumor maintenance, progression, treatment resistance, and recurrence. We believe that better understanding how epigenetic mechanisms operate in neural cells and identifying the etiologies and consequences of epigenetic deregulation in tumor cells and CSCs, in particular, are likely to promote the development of enhanced molecular diagnostics and more targeted and effective therapeutic agents for treating recalcitrant nervous system tumors.

  2. Peculiarities of antioxidant system and iron metabolism in organism during development of tumor resistance to cisplatin.

    Science.gov (United States)

    Chekhun, V F; Lozovska, Y V; Burlaka, A P; Lukyanova, N Y; Todor, I N; Naleskina, L A

    2014-09-01

    To study in vivo the peculiarities of changes of iron metabolism and antioxidant system in dynamics of growth of Guerin carcinoma with different sensitivity to cisplatin. In order to evaluate the content of metallothionein-1 (MT-1) in tumor homogenates and blood serum of rats with cisplatin-sensitive and cisplatin-resistant Guerin carcinoma the immunoenzyme method was used. The evaluation of ceruloplasmin activity, content of "free iron" complexes, superoxide and NO-generating acti-vity of NADPH-oxidase and iNOS activity in neutrophils, blood serum and tumor homogenates was measured by EPR-spectro-scopy. Maximal accumulation of MT-1 in blood serum and tumor, more pronounced in resistant strain, at the border of latent and exponential phase of growth has been shown that is the evidence of protective role of this protein in the respect to the generation of free radical compounds. It has been determined that in animals with cisplatin-resistant strain of Guerin carcinoma, increase of "free iron" complexes is more apparent both on the level of tumor and organism on the background on increase of CP/TR ratio that is the consequence of organism antioxidant protection system disorder. Mentioned changes in metabolism of iron with its accumulation in tumor and further reprogramming of mitochondria metabolism and activity of NADPH-oxidase for non-transformed cells are favorable conditions for the formation of oxidative phenotype of tumor.

  3. Leveraging Hypoxia-Activated Prodrugs to Prevent Drug Resistance in Solid Tumors.

    Directory of Open Access Journals (Sweden)

    Danika Lindsay

    2016-08-01

    Full Text Available Experimental studies have shown that one key factor in driving the emergence of drug resistance in solid tumors is tumor hypoxia, which leads to the formation of localized environmental niches where drug-resistant cell populations can evolve and survive. Hypoxia-activated prodrugs (HAPs are compounds designed to penetrate to hypoxic regions of a tumor and release cytotoxic or cytostatic agents; several of these HAPs are currently in clinical trial. However, preliminary results have not shown a survival benefit in several of these trials. We hypothesize that the efficacy of treatments involving these prodrugs depends heavily on identifying the correct treatment schedule, and that mathematical modeling can be used to help design potential therapeutic strategies combining HAPs with standard therapies to achieve long-term tumor control or eradication. We develop this framework in the specific context of EGFR-driven non-small cell lung cancer, which is commonly treated with the tyrosine kinase inhibitor erlotinib. We develop a stochastic mathematical model, parametrized using clinical and experimental data, to explore a spectrum of treatment regimens combining a HAP, evofosfamide, with erlotinib. We design combination toxicity constraint models and optimize treatment strategies over the space of tolerated schedules to identify specific combination schedules that lead to optimal tumor control. We find that (i combining these therapies delays resistance longer than any monotherapy schedule with either evofosfamide or erlotinib alone, (ii sequentially alternating single doses of each drug leads to minimal tumor burden and maximal reduction in probability of developing resistance, and (iii strategies minimizing the length of time after an evofosfamide dose and before erlotinib confer further benefits in reduction of tumor burden. These results provide insights into how hypoxia-activated prodrugs may be used to enhance therapeutic effectiveness in the

  4. Osteoclastic giant cell tumor of the pancreas: an immunohistochemical study

    DEFF Research Database (Denmark)

    Dizon, M A; Multhaupt, H A; Paskin, D L

    1996-01-01

    A case of an osteoclastic giant cell tumor of the pancreas is presented. Immunohistochemical studies were performed, which showed keratin (CAM, AE1) and epithelial membrane antigen positivity in the tumor cells. The findings support an epithelial origin for this tumor.......A case of an osteoclastic giant cell tumor of the pancreas is presented. Immunohistochemical studies were performed, which showed keratin (CAM, AE1) and epithelial membrane antigen positivity in the tumor cells. The findings support an epithelial origin for this tumor....

  5. Whole tumor antigen vaccination using dendritic cells: Comparison of RNA electroporation and pulsing with UV-irradiated tumor cells

    Directory of Open Access Journals (Sweden)

    Benencia Fabian

    2008-04-01

    Full Text Available Abstract Because of the lack of full characterization of tumor associated antigens for solid tumors, whole antigen use is a convenient approach to tumor vaccination. Tumor RNA and apoptotic tumor cells have been used as a source of whole tumor antigen to prepare dendritic cell (DC based tumor vaccines, but their efficacy has not been directly compared. Here we compare directly RNA electroporation and pulsing of DCs with whole tumor cells killed by ultraviolet (UV B radiation using a convenient tumor model expressing human papilloma virus (HPV E6 and E7 oncogenes. Although both approaches led to DCs presenting tumor antigen, electroporation with tumor cell total RNA induced a significantly higher frequency of tumor-reactive IFN-gamma secreting T cells, and E7-specific CD8+ lymphocytes compared to pulsing with UV-irradiated tumor cells. DCs electroporated with tumor cell RNA induced a larger tumor infiltration by T cells and produced a significantly stronger delay in tumor growth compared to DCs pulsed with UV-irradiated tumor cells. We conclude that electroporation with whole tumor cell RNA and pulsing with UV-irradiated tumor cells are both effective in eliciting antitumor immune response, but RNA electroporation results in more potent tumor vaccination under the examined experimental conditions.

  6. Enhancement of anticancer effect of interferon-γ gene transfer against interferon-γ-resistant tumor by depletion of tumor-associated macrophages.

    Science.gov (United States)

    Kiyota, Tsuyoshi; Takahashi, Yuki; Watcharanurak, Kanitta; Nishikawa, Makiya; Ohara, Saori; Ando, Mitsuru; Watanabe, Yoshihiko; Takakura, Yoshinobu

    2014-05-05

    Tumor-associated macrophages (TAMs) negatively affect the therapeutic effects of anticancer agents. To examine the role of TAMs in interferon (IFN)-γ gene therapy, we selected two types of solid tumors, which varied in the number of TAMs, and investigated the effects of IFN-γ gene transfer on tumor growth. Many TAMs were detected in the solid tumors of murine adenocarcinoma colon-26 cells, whereas few TAMs were detected in murine melanoma B16-BL6 cells. IFN-γ gene transfer hardly suppressed the growth of colon-26 tumors, whereas it was effective in suppressing the growth of B16-BL6 tumors. The antiproliferative effects of IFN-γ on cultured colon-26 cells were similar to those on cultured B16-BL6 cells. To evaluate the role of TAMs, we injected clodronate liposomes (CLs) modified with poly(ethylene glycol) (PEG) to functionally deplete TAMs in tumor-bearing mice. Repeated injections of PEG-CLs significantly retarded the growth of colon-26 tumors and combination with IFN-γ gene transfer further inhibited the growth. In contrast, PEG-CLs hardly retarded the growth of B16-BL6 tumors. These results clearly indicate that TAM depletion is effective in enhancing the therapeutic effect of IFN-γ in TAM-repleted and IFN-γ-resistant tumors.

  7. Ellagic acid radiosensitizes tumor cells by evoking apoptotic pathway

    International Nuclear Information System (INIS)

    Ahire, Vidhula R.; Mishra, K.P.

    2016-01-01

    Cancer causes millions of deaths each year globally. In most patients, the cause of treatment failure is found associated with the resistance to chemotherapy and radiotherapy. The development of tumor cell resistance evokes multiple intracellular molecular pathways. In addition, the limitation in treatment outcome arises due to unintended cytotoxic effects of the synthetic anticancer drugs to normal cells and tissues. Considerable focus of research is, therefore, devoted to examine plant-based herbal compounds which may prove potential anticancer drug for developing effective cancer therapy. Research results from our laboratory have shown that ellagic acid (EA), a natural flavonoid displays enhanced tumor toxicity in combination with gamma radiation to many types of cancers in vitro as well as in vivo. Studies on the underlying mechanisms of toxicity suggest that EA employs the cellular signaling pathways in producing the observed effects. This paper gives an account of molecular mechanisms of EA-induced apoptosis process in tumor cytotoxicity. It is suggested that EA acts as a novel radiosensitizer for tumors and a radioprotector for normal cells which may offer a novel protocol for cancer treatment. (author)

  8. Bisphenol A activates EGFR and ERK promoting proliferation, tumor spheroid formation and resistance to EGFR pathway inhibition in estrogen receptor negative inflammatory breast cancer cells

    Science.gov (United States)

    Background: Inflammatory breast cancer (IBC) is a distinct and the deadliest breast cancer variant, which shows a rapid rate of progression and acquired therapeutic resistance. Epidemiological studies suggest that chemical exposure in the environment and consumer products can aff...

  9. Exosomes promote cetuximab resistance via the PTEN/Akt pathway in colon cancer cells.

    Science.gov (United States)

    Zhang, S; Zhang, Y; Qu, J; Che, X; Fan, Y; Hou, K; Guo, T; Deng, G; Song, N; Li, C; Wan, X; Qu, X; Liu, Y

    2017-11-13

    Cetuximab is widely used in patients with metastatic colon cancer expressing wildtype KRAS. However, acquired drug resistance limits its clinical efficacy. Exosomes are nanosized vesicles secreted by various cell types. Tumor cell-derived exosomes participate in many biological processes, including tumor invasion, metastasis, and drug resistance. In this study, exosomes derived from cetuximab-resistant RKO colon cancer cells induced cetuximab resistance in cetuximab-sensitive Caco-2 cells. Meanwhile, exosomes from RKO and Caco-2 cells showed different levels of phosphatase and tensin homolog (PTEN) and phosphor-Akt. Furthermore, reduced PTEN and increased phosphorylated Akt levels were found in Caco-2 cells after exposure to RKO cell-derived exosomes. Moreover, an Akt inhibitor prevented RKO cell-derived exosome-induced drug resistance in Caco-2 cells. These findings provide novel evidence that exosomes derived from cetuximab-resistant cells could induce cetuximab resistance in cetuximab-sensitive cells, by downregulating PTEN and increasing phosphorylated Akt levels.

  10. Efficacy of a Cell-Cycle Decoying Killer Adenovirus on 3-D Gelfoam®-Histoculture and Tumor-Sphere Models of Chemo-Resistant Stomach Carcinomatosis Visualized by FUCCI Imaging.

    Directory of Open Access Journals (Sweden)

    Shuya Yano

    Full Text Available Stomach cancer carcinomatosis peritonitis (SCCP is a recalcitrant disease. The goal of the present study was to establish an in vitro-in vivo-like imageable model of SCCP to develop cell-cycle-based therapeutics of SCCP. We established 3-D Gelfoam® histoculture and tumor-sphere models of SCCP. FUCCI-expressing MKN-45 stomach cancer cells were transferred to express the fluorescence ubiquinized cell-cycle indicator (FUCCI. FUCCI-expressing MKN-45 cells formed spheres on agarose or on Gelfoam® grew into tumor-like structures with G0/G1 cancer cells in the center and S/G2 cancer cells located in the surface as indicated by FUCCI imaging when the cells fluoresced red or green, respectively. We treated FUCCI-expressing cancer cells forming SCCP tumors in Gelfoam® histoculture with OBP-301, cisplatinum (CDDP, or paclitaxel. CDDP or paclitaxel killed only cycling cancer cells and were ineffective against G1/G2 MKN-45 cells in tumors growing on Gelfoam®. In contrast, the telomerase-dependent adenovirus OBP-301 decoyed the MKN-45 cells in tumors on Gelfoam® to cycle from G0/G1 phase to S/G2 phase and reduced their viability. CDDP- or paclitaxel-treated MKN-45 tumors remained quiescent and did not change in size. In contrast, OB-301 reduced the size of the MKN-45 tumors on Gelfoam®. We examined the cell cycle-related proteins using Western blotting. CDDP increased the expression of p53 and p21 indicating cell cycle arrest. In contrast, OBP-301 decreased the expression of p53 and p21 Furthermore, OBP-301 increased the expression of E2F and pAkt as further indication of cell cycle decoy. This 3-D Gelfoam® histoculture and FUCCI imaging are powerful tools to discover effective therapy of SCCP such as OBP-301.

  11. Efficacy of a Cell-Cycle Decoying Killer Adenovirus on 3-D Gelfoam®-Histoculture and Tumor-Sphere Models of Chemo-Resistant Stomach Carcinomatosis Visualized by FUCCI Imaging

    Science.gov (United States)

    Yano, Shuya; Takehara, Kiyoto; Tazawa, Hiroshi; Kishimoto, Hiroyuki; Urata, Yasuo; Kagawa, Shunsuke; Fujiwara, Toshiyoshi; Hoffman, Robert M.

    2016-01-01

    Stomach cancer carcinomatosis peritonitis (SCCP) is a recalcitrant disease. The goal of the present study was to establish an in vitro-in vivo-like imageable model of SCCP to develop cell-cycle-based therapeutics of SCCP. We established 3-D Gelfoam® histoculture and tumor-sphere models of SCCP. FUCCI-expressing MKN-45 stomach cancer cells were transferred to express the fluorescence ubiquinized cell-cycle indicator (FUCCI). FUCCI-expressing MKN-45 cells formed spheres on agarose or on Gelfoam® grew into tumor-like structures with G0/G1 cancer cells in the center and S/G2 cancer cells located in the surface as indicated by FUCCI imaging when the cells fluoresced red or green, respectively. We treated FUCCI-expressing cancer cells forming SCCP tumors in Gelfoam® histoculture with OBP-301, cisplatinum (CDDP), or paclitaxel. CDDP or paclitaxel killed only cycling cancer cells and were ineffective against G1/G2 MKN-45 cells in tumors growing on Gelfoam®. In contrast, the telomerase-dependent adenovirus OBP-301 decoyed the MKN-45 cells in tumors on Gelfoam® to cycle from G0/G1 phase to S/G2 phase and reduced their viability. CDDP- or paclitaxel-treated MKN-45 tumors remained quiescent and did not change in size. In contrast, OB-301 reduced the size of the MKN-45 tumors on Gelfoam®. We examined the cell cycle-related proteins using Western blotting. CDDP increased the expression of p53 and p21 indicating cell cycle arrest. In contrast, OBP-301 decreased the expression of p53 and p21 Furthermore, OBP-301 increased the expression of E2F and pAkt as further indication of cell cycle decoy. This 3-D Gelfoam® histoculture and FUCCI imaging are powerful tools to discover effective therapy of SCCP such as OBP-301. PMID:27673332

  12. Tumor-Infiltrating Immune Cells Promoting Tumor Invasion and Metastasis: Existing Theories

    Directory of Open Access Journals (Sweden)

    Yan-gao Man, Alexander Stojadinovic, Jeffrey Mason, Itzhak Avital, Anton Bilchik, Bjoern Bruecher, Mladjan Protic, Aviram Nissan, Mina Izadjoo, Xichen Zhang, Anahid Jewett

    2013-01-01

    Full Text Available It is a commonly held belief that infiltration of immune cells into tumor tissues and direct physical contact between tumor cells and infiltrated immune cells is associated with physical destructions of the tumor cells, reduction of the tumor burden, and improved clinical prognosis. An increasing number of studies, however, have suggested that aberrant infiltration of immune cells into tumor or normal tissues may promote tumor progression, invasion, and metastasis. Neither the primary reason for these contradictory observations, nor the mechanism for the reported diverse impact of tumor-infiltrating immune cells has been elucidated, making it difficult to judge the clinical implications of infiltration of immune cells within tumor tissues. This mini-review presents several existing hypotheses and models that favor the promoting impact of tumor-infiltrating immune cells on tumor invasion and metastasis, and also analyzes their strength and weakness.

  13. Perivascular Epithelioid Cell Tumor in the Stomach

    Directory of Open Access Journals (Sweden)

    Sun Ah Shin

    2017-07-01

    Full Text Available Perivascular epithelioid cell tumors or PEComas can arise in any location in the body. However, a limited number of cases of gastric PEComa have been reported. We present two cases of gastric PEComas. The first case involved a 62-year-old woman who presented with a 4.2 cm gastric subepithelial mass in the prepyloric antrum, and the second case involved a 67-year-old man with a 5.0 cm mass slightly below the gastroesophageal junction. Microscopic examination revealed that both tumors were composed of perivascular epithelioid cells that were immunoreactive for melanocytic and smooth muscle markers. Prior to surgery, the clinical impression of both tumors was gastrointestinal stromal tumor (GIST, and the second case was erroneously diagnosed as GIST even after microscopic examination. Although gastric PEComa is a very rare neoplasm, it should be considered in the differential diagnosis of gastric submucosal lesions.

  14. Adenomatoid odontogenic tumor with clear cell changes

    Directory of Open Access Journals (Sweden)

    Neeta Mohanty

    2014-01-01

    Full Text Available Adenomatoid odontogenic tumor (AOT has a limited biological profile and been an attention-grabbing tumor for a century for its origin. Though described earlier, it was widely accepted after Harbitz from Norway reported about this uncommon benign tumor in 1915. There has been a long debate as whether this tumor is a hamartoma or a neoplasm. Here, we present a case of AOT in a 20-year-old female with details of clinical, radiological and histological features along with clear cell changes, signifying AOT to be more aggressive in nature than assessed from earlier literature. Thus, we did an extensive search of PubMed literature on AOT with all its histopathological features associated until date to find the report of clear cell changes yet.

  15. Circulating Tumor Cells Versus Circulating Tumor DNA in Colorectal Cancer: Pros and Cons.

    Science.gov (United States)

    Tan, Carlyn Rose C; Zhou, Lanlan; El-Deiry, Wafik S

    2016-06-01

    Circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) are emerging noninvasive multifunctional biomarkers in liquid biopsy allowing for early diagnosis, accurate prognosis, therapeutic target selection, spatiotemporal monitoring of metastasis, as well as monitoring response and resistance to treatment. CTCs and ctDNA are released from different tumor types at different stages and contribute complementary information for clinical decision. Although big strides have been taken in technology development for detection, isolation and characterization of CTCs and sensitive and specific detection of ctDNA, CTC-, and ctDNA-based liquid biopsies may not be widely adopted for routine cancer patient care until the suitability, accuracy, and reliability of these tests are validated and more standardized protocols are corroborated in large, independent, prospectively designed trials. This review covers CTC- and ctDNA-related technologies and their application in colorectal cancer. The promise of CTC-and ctDNA-based liquid biopsies is envisioned.

  16. Tumor suppressor WWOX and p53 alterations and drug resistance in glioblastomas

    Directory of Open Access Journals (Sweden)

    Ming-Fu eChiang

    2013-03-01

    Full Text Available Tumor suppressor p53 are frequently mutated in glioblastomas (GBMs and appears to contribute, in part, to resistance to temozolomide and therapeutic drugs. WW domain-containing oxidoreductase WWOX (FOR or WOX1 is a proapoptotic protein and is considered as a tumor suppressor. Loss of WWOX gene expression is frequently seen in malignant cancer cells due to promoter hypermethylation, genetic alterations, and translational blockade. Intriguingly, ectopic expression of wild type WWOX preferentially induces apoptosis in human glioblastoma cells harboring mutant p53. WWOX is known to physically bind and stabilize wild type p53. Here, we provide an overview for the updated knowledge in p53 and WWOX, and postulate a potential scenarios that wild type and mutant p53, or isoforms, modulate the apoptotic function of WWOX. We propose that triggering WWOX activation by therapeutic drugs under p53 functional deficiency is needed to overcome TMZ resistance and induce GBM cell death.

  17. The Human Cell Surfaceome of Breast Tumors

    Science.gov (United States)

    da Cunha, Júlia Pinheiro Chagas; Galante, Pedro Alexandre Favoretto; de Souza, Jorge Estefano Santana; Pieprzyk, Martin; Carraro, Dirce Maria; Old, Lloyd J.; Camargo, Anamaria Aranha; de Souza, Sandro José

    2013-01-01

    Introduction. Cell surface proteins are ideal targets for cancer therapy and diagnosis. We have identified a set of more than 3700 genes that code for transmembrane proteins believed to be at human cell surface. Methods. We used a high-throuput qPCR system for the analysis of 573 cell surface protein-coding genes in 12 primary breast tumors, 8 breast cell lines, and 21 normal human tissues including breast. To better understand the role of these genes in breast tumors, we used a series of bioinformatics strategies to integrates different type, of the datasets, such as KEGG, protein-protein interaction databases, ONCOMINE, and data from, literature. Results. We found that at least 77 genes are overexpressed in breast primary tumors while at least 2 of them have also a restricted expression pattern in normal tissues. We found common signaling pathways that may be regulated in breast tumors through the overexpression of these cell surface protein-coding genes. Furthermore, a comparison was made between the genes found in this report and other genes associated with features clinically relevant for breast tumorigenesis. Conclusions. The expression profiling generated in this study, together with an integrative bioinformatics analysis, allowed us to identify putative targets for breast tumors. PMID:24195083

  18. Malignant Solitary Fibrous Tumor Metastatic to Widely Invasive Hurthle Cell Thyroid Carcinoma: A Distinct Tumor-to-Tumor Metastasis.

    Science.gov (United States)

    Kolson Kokohaare, Eva; Riva, Francesco M G; Bernstein, Jonathan M; Miah, Aisha B; Thway, Khin

    2018-04-01

    We illustrate a case of synchronous malignant solitary fibrous tumor of the thoracic cavity, and widely invasive thyroid Hurthle cell carcinoma. The Hurthle cell carcinoma was found to harbor distinct areas of malignant solitary fibrous tumor. This is a unique case of tumor-to-tumor metastasis that, to the best of our knowledge, has not been previously reported.

  19. Nanoparticle-mediated combination chemotherapy and photodynamic therapy overcomes tumor drug resistance in vitro.

    Science.gov (United States)

    Khdair, Ayman; Handa, Hitesh; Mao, Guangzhao; Panyam, Jayanth

    2009-02-01

    Drug resistance limits the success of many anticancer drugs. Reduced accumulation of the drug at its intracellular site of action because of overexpression of efflux transporters such as P-glycoprotein (P-gp) is a major mechanism of drug resistance. In this study, we investigated whether photodynamic therapy (PDT) using methylene blue, also a P-gp inhibitor, can be used to enhance doxorubicin-induced cytotoxicity in drug-resistant tumor cells. Aerosol OT (AOT)-alginate nanoparticles were used as a carrier for the simultaneous cellular delivery of doxorubicin and methylene blue. Methylene blue was photoactivated using light of 665 nm wavelength. Induction of apoptosis and necrosis following treatment with combination chemotherapy and PDT was investigated in drug-resistant NCI/ADR-RES cells using flow cytometry and fluorescence microscopy. Effect of encapsulation in nanoparticles on the intracellular accumulation of doxorubicin and methylene blue was investigated qualitatively using fluorescence microscopy and was quantitated using HPLC. Encapsulation in AOT-alginate nanoparticles significantly enhanced the cytotoxicity of combination therapy in resistant tumor cells. Nanoparticle-mediated combination therapy resulted in a significant induction of both apoptosis and necrosis. Improvement in cytotoxicity could be correlated with enhanced intracellular and nuclear delivery of the two drugs. Further, nanoparticle-mediated combination therapy resulted in significantly elevated reactive oxygen species (ROS) production compared to single drug treatment. In conclusion, nanoparticle-mediated combination chemotherapy and PDT using doxorubicin and methylene blue was able to overcome resistance mechanisms and resulted in improved cytotoxicity in drug-resistant tumor cells.

  20. Hypofractionation results in reduced tumor cell kill compared to conventional fractionation for tumors with regions of hypoxia.

    Science.gov (United States)

    Carlson, David J; Keall, Paul J; Loo, Billy W; Chen, Zhe J; Brown, J Martin

    2011-03-15

    Tumor hypoxia has been observed in many human cancers and is associated with treatment failure in radiation therapy. The purpose of this study is to quantify the effect of different radiation fractionation schemes on tumor cell killing, assuming a realistic distribution of tumor oxygenation. A probability density function for the partial pressure of oxygen in a tumor cell population is quantified as a function of radial distance from the capillary wall. Corresponding hypoxia reduction factors for cell killing are determined. The surviving fraction of a tumor consisting of maximally resistant cells, cells at intermediate levels of hypoxia, and normoxic cells is calculated as a function of dose per fraction for an equivalent tumor biological effective dose under normoxic conditions. Increasing hypoxia as a function of distance from blood vessels results in a decrease in tumor cell killing for a typical radiotherapy fractionation scheme by a factor of 10(5) over a distance of 130 μm. For head-and-neck cancer and prostate cancer, the fraction of tumor clonogens killed over a full treatment course decreases by up to a factor of ∼10(3) as the dose per fraction is increased from 2 to 24 Gy and from 2 to 18 Gy, respectively. Hypofractionation of a radiotherapy regimen can result in a significant decrease in tumor cell killing compared to standard fractionation as a result of tumor hypoxia. There is a potential for large errors when calculating alternate fractionations using formalisms that do not account for tumor hypoxia. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Amplification of tumor inducing putative cancer stem cells (CSCs) by vitamin A/retinol from mammary tumors

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Rohit B. [Department of Microbiology and Molecular Genetics, University of Pittsburgh, PA 15261 (United States); Wang, Qingde [Department of Surgery, University of Pittsburgh, PA 15261 (United States); Khillan, Jaspal S., E-mail: khillan@pitt.edu [Department of Microbiology and Molecular Genetics, University of Pittsburgh, PA 15261 (United States)

    2013-07-12

    Highlights: •Vitamin A supports self renewal of putative CSCs from mammary tumors. •These cells exhibit impaired retinol metabolism into retinoic acid. •CSCs from mammary tumors differentiate into mammary specific cell lineages. •The cells express mammary stem cell specific CD29 and CD49f markers. •Putative CSCs form highly metastatic tumors in NOD SCID mouse. -- Abstract: Solid tumors contain a rare population of cancer stem cells (CSCs) that are responsible for relapse and metastasis. The existence of CSC however, remains highly controversial issue. Here we present the evidence for putative CSCs from mammary tumors amplified by vitamin A/retinol signaling. The cells exhibit mammary stem cell specific CD29{sup hi}/CD49f{sup hi}/CD24{sup hi} markers, resistance to radiation and chemo therapeutic agents and form highly metastatic tumors in NOD/SCID mice. The cells exhibit indefinite self renewal as cell lines. Furthermore, the cells exhibit impaired retinol metabolism and do not express enzymes that metabolize retinol into retinoic acid. Vitamin A/retinol also amplified putative CSCs from breast cancer cell lines that form highly aggressive tumors in NOD SCID mice. The studies suggest that high purity putative CSCs can be isolated from solid tumors to establish patient specific cell lines for personalized therapeutics for pre-clinical translational applications. Characterization of CSCs will allow understanding of basic cellular and molecular pathways that are deregulated, mechanisms of tumor metastasis and evasion of therapies that has direct clinical relevance.

  2. Collateral methotrexate resistance in cisplatin-selected murine leukemia cells

    Directory of Open Access Journals (Sweden)

    Bhushan A.

    1999-01-01

    Full Text Available Resistance to anticancer drugs is a major cause of failure of many therapeutic protocols. A variety of mechanisms have been proposed to explain this phenomenon. The exact mechanism depends upon the drug of interest as well as the tumor type treated. While studying a cell line selected for its resistance to cisplatin we noted that the cells expressed a >25,000-fold collateral resistance to methotrexate. Given the magnitude of this resistance we elected to investigate this intriguing collateral resistance. From a series of investigations we have identified an alteration in a membrane protein of the resistant cell as compared to the sensitive cells that could be the primary mechanism of resistance. Our studies reviewed here indicate decreased tyrosine phosphorylation of a protein (molecular mass = 66 in the resistant cells, which results in little or no transfer of methotrexate from the medium into the cell. Since this is a relatively novel function for tyrosine phosphorylation, this information may provide insight into possible pharmacological approaches to modify therapeutic regimens by analyzing the status of this protein in tumor samples for a better survival of the cancer patients.

  3. Tumor initiating cells in malignant gliomas: biology and implications for therapy.

    Science.gov (United States)

    Hadjipanayis, Costas G; Van Meir, Erwin G

    2009-04-01

    A rare subpopulation of cells within malignant gliomas, which shares canonical properties with neural stem cells (NSCs), may be integral to glial tumor development and perpetuation. These cells, also known as tumor initiating cells (TICs), have the ability to self-renew, develop into any cell in the overall tumor population (multipotency), and proliferate. A defining property of TICs is their ability to initiate new tumors in immunocompromised mice with high efficiency. Mounting evidence suggests that TICs originate from the transformation of NSCs and their progenitors. New findings show that TICs may be more resistant to chemotherapy and radiation than the bulk of tumor cells, thereby permitting recurrent tumor formation and accounting for the failure of conventional therapies. The development of new therapeutic strategies selectively targeting TICs while sparing NSCs may provide for more effective treatment of malignant gliomas.

  4. Oriented collagen fibers direct tumor cell intravasation

    KAUST Repository

    Han, Weijing

    2016-09-24

    In this work, we constructed a Collagen I-Matrigel composite extracellular matrix (ECM). The composite ECM was used to determine the influence of the local collagen fiber orientation on the collective intravasation ability of tumor cells. We found that the local fiber alignment enhanced cell-ECM interactions. Specifically, metastatic MDA-MB-231 breast cancer cells followed the local fiber alignment direction during the intravasation into rigid Matrigel (∼10 mg/mL protein concentration).

  5. Giant cell tumor of bone: Multimodal approach

    Directory of Open Access Journals (Sweden)

    Gupta A

    2007-01-01

    Full Text Available Background: The clinical behavior and treatment of giant cell tumor of bone is still perplexing. The aim of this study is to clarify the clinico-pathological correlation of tumor and its relevance in treatment and prognosis. Materials and Methods: Ninety -three cases of giant cell tumor were treated during 1980-1990 by different methods. The age of the patients varied from 18-58 yrs with male and female ratio as 5:4. The upper end of the tibia was most commonly involved (n=31, followed by the lower end of the femur(n=21, distal end of radius(n=14,upper end of fibula (n=9,proximal end of femur(n=5, upper end of the humerus(n=3, iliac bone(n=2,phalanx (n=2 and spine(n=1. The tumors were also encountered on uncommon sites like metacarpals (n=4 and metatarsal(n=1. Fifty four cases were treated by curettage and bone grafting. Wide excision and reconstruction was performed in twenty two cases . Nine cases were treated by wide excision while primary amputation was performed in four cases. One case required only curettage. Three inaccessible lesions of ilium and spine were treated by radiotherapy. Results: 19 of 54 treated by curettage and bone grafting showed a recurrence. The repeat curettage and bone grafting was performed in 18 cases while amputation was done in one. One each out of the cases treated by wide excision and reconstruction and wide excision alone recurred. In this study we observed that though curettage and bone grafting is still the most commonly adopted treatment, wide excision of tumor with reconstruction has shown lesser recurrence. Conclusion: For radiologically well-contained and histologically typical tumor, curettage and autogenous bone grafting is the treatment of choice . The typical tumors with radiologically deficient cortex, clinically aggressive tumors and tumors with histological Grade III should be treated by wide excision and reconstruction.

  6. Radiotherapy of patients with germ cell tumor

    International Nuclear Information System (INIS)

    Inomata, Taisuke; Maeda, Tomoho; Yoshida, Shoji; Ogawa, Yasuhiro; Hamada, Fumio; Imajo, Yoshinari; Gose, Kyuhei; Fujiwara, Kiyoshi.

    1986-01-01

    Twenty-one patients with germ cell tumor who received radiotherapy were discussed. There were eight patients with germinoma, two patients with malignant teratoma, three patients with pineocytoma (out of category of germ cell tumor today) and eight unverified patients. Irradiated dose was mostly from 50 Gy to 60 Gy and local irradiation was performed after whole brain irradiation in many cases. The effect of radiotherapy was not so good in patients with malignant teratoma. On the contrary, it was relatively good in patients with germinoma and five out of eight patients are alive with no symptoms of recurrence. Six out of eight unverified patients are also alive. Among them, several patients with germinoma are considered to be included. Germinoma occupies many cases of germ cell tumor and has a good response to radiotherapy. Against spinal cord metastasis and late recurrence, additional therapy, such as chemotherapy, seems to be useful to improve cure ratio. (author)

  7. Granular cells Tumor in the gastrointestinal tract

    International Nuclear Information System (INIS)

    Castano LL, Rodrigo; Gaitan B, Maria H; Juliao E, Fabian

    2005-01-01

    Granular cells tumors are ubiquitous lesions in the gastrointestinal tract, are rare and asymptomatic and they are generally an incidental discovery at gastroduodenoscopy or colonoscopy. In the gastrointestinal tract they are more frequently located in the esophagus, right colon and rectum, stomach, appendix, small intestine or biliopancreatic tract. This article describes three patients with four tumors of granular cells in rectum, esophagus (2 lesions) and appendix. It becomes special emphasis in their neural origin, their benign behavior that justifies the endoscopic resections or limited surgical excisions and the necessity of a pursuit for the possibility, although little, of malignant transformation

  8. [Relationship between sensitivity of tumor cells to chemotherapeutic agent in vivo and in vitro: experiment with mouse lymphoma cells].

    Science.gov (United States)

    Li, Chuan-gang; Li, Mo-lin; Shu, Xiao-hong; Jia, Yu-jie; Liu, Yong-ji; Li, Ming

    2007-06-12

    To study the relationship of the sensitivity of tumor cells to chemotherapeutic agent between in vivo and in vitro. Mouse lymphoma cells of the line E14 were cultured and melphalan resistant EL4 cell line (EL4/melphalan) was established by culturing EL4 cells with continuous low-concentration and intermittent gradually-increasing-concentration of melphalan in vitro. MTT assay was used to evaluate the drug sensitivity and the resistance index of the EL4/melphalan cells to melphalan was calculated. EL4/melphalan and EL4 cells of the concentration of 5 x 10(8)/L were inoculated separately into 20 C57BL/6 mice subcutaneously. 12 days later, the EL4 and EL4/melphalan tumor-bearing mice were randomly divided into 2 groups respectively, 5 mice in each group. Treatment groups were given 7.5 mg/kg melphalan intraperitoneally, and control groups were given the same volume of normal saline. The tumor size was observed every other day. Compared with the EL4 cells, the EL4/melphalan cells had no obvious changes morphologically. They could grow in RPMI 1640 medium containing 5 mg/ml melphalan. The resistance index was 2.87 against melphalan. After the treatment of melphalan of the dose 7.5 mg/kg, the tumor sizes of the treatment groups and control groups inoculated with both EL4 cells and the EL4/melphalan cells gradually decreased at the similar speed, and about one week later all tumors disappeared. However, the tumors of the control groups grew progressively and all the mice died at last. The chemotherapeutic effects of tumors in vivo have nothing to do with the effects of the chemotherapeutic agents on tumor cells in vitro. The tumor cells resistant to melphalan in vitro remain sensitive to the drug in vivo.

  9. Escape from Tumor Cell Dormancy

    Science.gov (United States)

    2012-10-01

    for metastatic cell arrest in distant organs. Neoplasia, 7(5), 522-7 (2005) 170. K. A . Paschos, D. Canovas and N. C. Bird : The role of cell adhesion...overnight in a 608C oven . Polymerized PDMS micropatterned stamps were peeled off the silicon master and used for patterning the PEG–fibrinogen...to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE

  10. Granulosa cell tumor of ovary: US findings

    International Nuclear Information System (INIS)

    Jin, Yong Hyun; Jeon, Hae Jeong; Lee, Chang Dea; Cho, Young Kwon; Kang, Chang Ho; Park, Yong Hyun; Kim, Myung Gyu; Lee, Yeon Hee; Kim, Young Hwa; Lee, Hye Kyung

    1999-01-01

    To describe ultrasonographic findings of ovarian granulosa cell tumor (GCT) and to determine their possible value in the differential diagnosis of ovarian tumors. Sonographic appearances of ten cases of pathologically proven GC Ts were retrospectively reviewed regarding their location, size, outer margin, the echo pattern of the tumor, endometrial thickness, presence of ascites, and metastasis to adjacent tissue or distant sites. 3.0-3.5 MHz trans-abdominal US or 5.0-6.5 MHz transvaginal US were used. The sonographic features could be classified as follows: unilocular cystic mass without nodule or septation (type 1), multilocular cystic mass (type 2), and solid mass (type 3). Pathologically nine cases were adult type granulosa cell tumors (GCT) and one was a juvenile type. All cases were unilateral. GCT arising from left ovary were seven, right, three. The largest diameter of the tumors ranged from 6.8 to 24 cm (mean: 11.9 cm). All had well-defined margins. Ascites was seen in four cases. Among ten cases of GCT, six were mainly solid (type 3). One case manifested as a unilocular cystic mass without mural nodule or septation. Three were multilocular cystic masses and no mural nodule was found in all three cases. Metastases to peritoneum and lymph nodes was seen in one case. The ultrasonographic findings of GCT are various but combined with clinical and laboratory findings they could be helpful in the differential diagnosis of ovarian tumors.

  11. Granulosa cell tumor of ovary: US findings

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Yong Hyun; Jeon, Hae Jeong; Lee, Chang Dea; Cho, Young Kwon [Kun Kuk University School of Medicine, Seoul (Korea, Republic of); Kang, Chang Ho; Park, Yong Hyun [Korea University School of Medicine, Seoul (Korea, Republic of); Kim, Myung Gyu [Korea University School of Medicine, Seoul (Korea, Republic of); Lee, Yeon Hee [Kang Nam Cha General Hospital, Seoul (Korea, Republic of); Kim, Young Hwa; Lee, Hye Kyung [Dan Kuk University School of Medicine (Korea, Republic of)

    1999-06-15

    To describe ultrasonographic findings of ovarian granulosa cell tumor (GCT) and to determine their possible value in the differential diagnosis of ovarian tumors. Sonographic appearances of ten cases of pathologically proven GC Ts were retrospectively reviewed regarding their location, size, outer margin, the echo pattern of the tumor, endometrial thickness, presence of ascites, and metastasis to adjacent tissue or distant sites. 3.0-3.5 MHz trans-abdominal US or 5.0-6.5 MHz transvaginal US were used. The sonographic features could be classified as follows: unilocular cystic mass without nodule or septation (type 1), multilocular cystic mass (type 2), and solid mass (type 3). Pathologically nine cases were adult type granulosa cell tumors (GCT) and one was a juvenile type. All cases were unilateral. GCT arising from left ovary were seven, right, three. The largest diameter of the tumors ranged from 6.8 to 24 cm (mean: 11.9 cm). All had well-defined margins. Ascites was seen in four cases. Among ten cases of GCT, six were mainly solid (type 3). One case manifested as a unilocular cystic mass without mural nodule or septation. Three were multilocular cystic masses and no mural nodule was found in all three cases. Metastases to peritoneum and lymph nodes was seen in one case. The ultrasonographic findings of GCT are various but combined with clinical and laboratory findings they could be helpful in the differential diagnosis of ovarian tumors.

  12. Imatinib mesylate inhibits Leydig cell tumor growth: evidence for in vitro and in vivo activity.

    Science.gov (United States)

    Basciani, Sabrina; Brama, Marina; Mariani, Stefania; De Luca, Gabriele; Arizzi, Mario; Vesci, Loredana; Pisano, Claudio; Dolci, Susanna; Spera, Giovanni; Gnessi, Lucio

    2005-03-01

    Leydig cell tumors are usually benign tumors of the male gonad. However, if the tumor is malignant, no effective treatments are currently available. Leydig cell tumors express platelet-derived growth factor (PDGF), kit ligand and their respective receptors, PDGFR and c-kit. We therefore evaluated the effects of imatinib mesylate (imatinib), a selective inhibitor of the c-kit and PDGFR tyrosine kinases, on the growth of rodent Leydig tumor cell lines in vivo and in vitro, and examined, in human Leydig cell tumor samples, the expression of activated PDGFR and c-kit and the mutations in exons of the c-kit gene commonly associated with solid tumors. Imatinib caused concentration-dependent decreases in the viability of Leydig tumor cell lines, which coincided with apoptosis and inhibition of proliferation and ligand-stimulated phosphorylation of c-kit and PDGFRs. Mice bearing s.c. allografts of a Leydig tumor cell line treated with imatinib p.o., had an almost complete inhibition of tumor growth, less tumor cell proliferation, increased apoptosis, and a lesser amount of tumor-associated mean vessel density compared with controls. No drug-resistant tumors appeared during imatinib treatment but tumors regrew after drug withdrawal. Human Leydig cell tumors showed an intense expression of the phosphorylated form of c-kit and a less intense expression of phosphorylated PDGFRs. No activating mutations in common regions of mutation of the c-kit gene were found. Our studies suggest that Leydig cell tumors might be a potential target for imatinib therapy.

  13. Peculiarities in the CT findings of germ cell tumors in various tumor localizations

    International Nuclear Information System (INIS)

    Tazoe, Makoto; Miyagami, Mitsusuke; Tsubokawa, Takashi

    1991-01-01

    The CT findings of 17 germ cell tumors were studied in relation to the locations of the tumor, the pathological diagnoses, and the tumor markers (AFP and HCG). Generally, the CT findings of germ cell tumors depended on the pathological diagnoses more strongly than on the location of the tumors. On plain CT of 7 germ cell tumors in the pineal region, all of them demonstrated heterogeneous findings. Hydrocephalus was seen in 6 cases (86%) and calcification in 6 cases (86%) of the germ cell tumors in the pineal region. Calcification and hydrocephalus that appeared more often than in other regions were characteristic of germ cell tumors of the pineal region. The germ cell tumors in the basal ganglia had a slightly homogenous high density, with small cysts and calcification in most of them on plain CT. On enhanced CT, the tumors were moderately enhanced in all cases located in the basal ganglia. Four cases of germ cell tumors located in the basal ganglia revealed the dilatation of lateral ventricle due to hemispheric atrophy in the tumor side. The germ cell tumors showing an increase in the tumor markers such as AFP and HCG, which were usually malignant germ cell tumors, were strongly enhanced on enhanced CT. (author)

  14. Vasculatures in Tumors Growing From Preirradiated Tissues: Formed by Vasculogenesis and Resistant to Radiation and Antiangiogenic Therapy

    International Nuclear Information System (INIS)

    Chen, Fang-Hsin; Chiang, Chi-Shiun; Wang, Chun-Chieh; Fu, Sheng-Yung; Tsai, Chien-Sheng; Jung, Shih-Ming; Wen, Chih-Jen; Lee, Chung-Chi; Hong, Ji-Hong

    2011-01-01

    Purpose: To investigate vasculatures and microenvironment in tumors growing from preirradiated tissues (pre-IR tumors) and study the vascular responses of pre-IR tumors to radiation and antiangiogenic therapy. Methods and Materials: Transgenic adenocarcinoma of the mouse prostate C1 tumors were implanted into unirradiated or preirradiated tissues and examined for vascularity, hypoxia, and tumor-associated macrophage (TAM) infiltrates by immunohistochemistry. The origin of tumor endothelial cells was studied by green fluorescent protein-tagged bone marrow (GFP-BM) transplantation. The response of tumor endothelial cells to radiation and antiangiogenic agent was evaluated by apoptotic assay. Results: The pre-IR tumors had obvious tumor bed effects (TBE), with slower growth rate, lower microvascular density (MVD), and more necrotic and hypoxic fraction compared with control tumors. The vessels were dilated, tightly adhered with pericytes, and incorporated with transplanted GFP-BM cells. In addition, hypoxic regions became aggregated with TAM. As pre-IR tumors developed, the TBE was overcome at the tumor edge where the MVD increased, TAM did not aggregate, and the GFP-BM cells did not incorporate into the vessels. The vessels at tumor edge were more sensitive to the following ionizing radiation and antiangiogenic agent than those in the central low MVD regions. Conclusions: This study demonstrates that vasculatures in regions with TBE are mainly formed by vasculogenesis and resistant to radiation and antiangiogenic therapy. Tumor bed effects could be overcome at the edge of larger tumors, but where vasculatures are formed by angiogenesis and sensitive to both treatments. Vasculatures formed by vasculogenesis should be the crucial target for the treatment of recurrent tumors after radiotherapy.

  15. Ovarian Germ Cell Tumors Treatment

    Science.gov (United States)

    ... diagnosed, tests are done to find out if cancer cells have spread within the ovary or to other parts of the body. The process used to find out whether cancer has spread within the ovary or to other parts of the body is ...

  16. Circulating tumor cells: utopia or reality?

    Science.gov (United States)

    Conteduca, Vincenza; Zamarchi, Rita; Rossi, Elisabetta; Condelli, Valentina; Troiani, Laura; Aieta, Michele

    2013-09-01

    Circulating tumor cells (CTCs) could be considered a sign of tumor aggressiveness, but highly sensitive and specific methods of CTC detection are necessary owing to the rarity and heterogeneity of CTCs in peripheral blood. This review summarizes recent studies on tumor biology, with particular attention to the metastatic cascade, and the molecular characterization and clinical significance of CTCs. Recent technological approaches to enrich and detect these cells and challenges of CTCs for individualized cancer treatment are also discussed. This review also provides an insight into the positive and negative features of the future potential applications of CTC detection, which sometimes remains still a 'utopia', but its actual utility remains among the fastest growing research fields in oncology.

  17. Tumor of granular cells of esophagus

    International Nuclear Information System (INIS)

    Gonzalez Fabian, Licet; Diaz Anaya, Amnia; Perez de la Torre, Georgina

    2010-01-01

    Granular cells tumors are rare and asymptomatic lesions and by general, it is an incidental finding en high or low endoscopy. They were described for the first time by Abrikossoff in 1926. The more frequent locations are the buccal mucosa, dermis and subcutaneous cellular tissue, most of these tumors has a benign origin. This is the case of a woman aged 44 with a pyrosis history from a year ago; by high endoscopy it is noted a 8 mm lesion distal to esophagus and confirmed by histological study of granular cells tumor. Elective treatment of this lesion is the endoscopic polypectomy. Despite that the malign potential is low; we suggested a close clinical and endoscopic follow-up.

  18. Circulating Tumor Cells in Prostate Cancer

    International Nuclear Information System (INIS)

    Hu, Brian; Rochefort, Holly; Goldkorn, Amir

    2013-01-01

    Circulating tumor cells (CTCs) can provide a non-invasive, repeatable snapshot of an individual patient’s tumor. In prostate cancer, CTC enumeration has been extensively studied and validated as a prognostic tool and has received FDA clearance for use in monitoring advanced disease. More recently, CTC analysis has been shifting from enumeration to more sophisticated molecular characterization of captured cells, which serve as a “liquid biopsy” of the tumor, reflecting molecular changes in an individual’s malignancy over time. Here we will review the main CTC studies in advanced and localized prostate cancer, highlighting the important gains as well as the challenges posed by various approaches, and their implications for advancing prostate cancer management

  19. Emergent Stratification in Solid Tumors Selects for Reduced Cohesion of Tumor Cells: A Multi-Cell, Virtual-Tissue Model of Tumor Evolution Using CompuCell3D.

    Directory of Open Access Journals (Sweden)

    Maciej H Swat

    Full Text Available Tumor cells and structure both evolve due to heritable variation of cell behaviors and selection over periods of weeks to years (somatic evolution. Micro-environmental factors exert selection pressures on tumor-cell behaviors, which influence both the rate and direction of evolution of specific behaviors, especially the development of tumor-cell aggression and resistance to chemotherapies. In this paper, we present, step-by-step, the development of a multi-cell, virtual-tissue model of tumor somatic evolution, simulated using the open-source CompuCell3D modeling environment. Our model includes essential cell behaviors, microenvironmental components and their interactions. Our model provides a platform for exploring selection pressures leading to the evolution of tumor-cell aggression, showing that emergent stratification into regions with different cell survival rates drives the evolution of less cohesive cells with lower levels of cadherins and higher levels of integrins. Such reduced cohesivity is a key hallmark in the progression of many types of solid tumors.

  20. Circulating tumor cell counts are prognostic of overall survival in SWOG S0421: a phase III trial of docetaxel with or without atrasentan for metastatic castration-resistant prostate cancer.

    Science.gov (United States)

    Goldkorn, Amir; Ely, Benjamin; Quinn, David I; Tangen, Catherine M; Fink, Louis M; Xu, Tong; Twardowski, Przemyslaw; Van Veldhuizen, Peter J; Agarwal, Neeraj; Carducci, Michael A; Monk, J Paul; Datar, Ram H; Garzotto, Mark; Mack, Philip C; Lara, Primo; Higano, Celestia S; Hussain, Maha; Thompson, Ian Murchie; Cote, Richard J; Vogelzang, Nicholas J

    2014-04-10

    Circulating tumor cell (CTC) enumeration has not been prospectively validated in standard first-line docetaxel treatment for metastatic castration-resistant prostate cancer. We assessed the prognostic value of CTCs for overall survival (OS) and disease response in S0421, a phase III trial of docetaxel plus prednisone with or without atrasentan. CTCs were enumerated at baseline (day 0) and before cycle two (day 21) using CellSearch. Baseline counts and changes in counts from day 0 to 21 were evaluated for association with OS, prostate-specific antigen (PSA), and RECIST response using Cox regression as well as receiver operator characteristic (ROC) curves, integrated discrimination improvement (IDI) analysis, and regression trees. Median day-0 CTC count was five cells per 7.5 mL, and CTCs < versus ≥ five per 7.5 mL were significantly associated with baseline PSA, bone pain, liver disease, hemoglobin, alkaline phosphatase, and subsequent PSA and RECIST response. Median OS was 26 months for < five versus 13 months for ≥ five CTCs per 7.5 mL at day 0 (hazard ratio [HR], 2.74 [adjusting for covariates]). ROC curves had higher areas under the curve for day-0 CTCs than for PSA, and IDI analysis showed that adding day-0 CTCs to baseline PSA and other covariates increased predictive accuracy for survival by 8% to 10%. Regression trees yielded new prognostic subgroups, and rising CTC count from day 0 to 21 was associated with shorter OS (HR, 2.55). These data validate the prognostic utility of CTC enumeration in a large docetaxel-based prospective cohort. Baseline CTC counts were prognostic, and rising CTCs at 3 weeks heralded significantly worse OS, potentially serving as an early metric to help redirect and optimize therapy in this clinical setting.

  1. Radiologic findings of ovarian granulosa cell tumor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Chul [Chungnam National Univ. College of Medicine, Taejon (Korea, Republic of)

    1997-10-01

    To determine, through an analysis of radiologic findings, whether the findings of granulosa cell tumors (GCTs) of the ovary are specific. The radiologic findings (ultrasonography, computed tomography, and magnetic resonance imaging) of 16 pathologically proven ovarian GCTs in 15 patients were retrospectively analysed for the site of origin, staging, largest diameter, margin, solid and/or cystic components, degree of enhancement, and associated endometrial hyperplasia, ascites, and local and/or distant metastasis. Unilateral ovarian GCTs were found in 14 patients, and bilateral tumors in one. Of a total of 16 tumors, 13 were of the adult type, and three were juvenile; their largest diameter ranged from 1 to 26(mean, 15.6)cm. Eleven tumors were well-defined, two were cystic, and one small tumor was solid. Of 13 mixed tumors, three had hemorrhagic portions, and five had multilocular cystic portions. Metastases to the uterus, tubes, rectum, lymph nodes, or liver were found in six patients, and associated endometrial hyperplasia in two. Radiologically, ovarian GCTs showed well-defined or encapsulated soft tissue masses with some hemorrhagic, multilocular or focal cystic components, as well as associated endometrial thickening and local or distant metastasis. These and clinical findings may be useful in the diagnosis of ovarian GCTs.

  2. Microfluidic Platform for Circulating Tumor Cells Isolation

    Energy Technology Data Exchange (ETDEWEB)

    Figueras-Mari, I.; Rodriguez-Trujillo, L.; Samitier-Marti, J.

    2016-07-01

    Circulating tumor cells (CTCs) are released from primary tumors into the bloodstream and transported to distant organs, promoting metastasis, which is known to be responsible for most cancer‐related deaths. Currently tumors are not found until symptoms appear or by chance when the patient undergoes a medical test, which in both situations can be too late. Once a tumor is found it is studied from tissue samples obtained directly from the patient in an invasive way. This invasive procedure is known as biopsy and apart from being invasive, it is costly, time consuming and can sometimes be painful and even risky for the patients’ health condition. Therefore, CTCs detection in blood also addressed as “liquid biopsy” would be very useful because by running routine blood analysis CTCs could be detected and collected suggesting tumor presence. However, due to the scarce presence in blood of these cells and to the huge amount of contamination from other cellular components a perfect method providing good capture and purity of CTCs has not been developed yet. In this project, a spiral size sorter microfluidic device has been manufactured and tested in order to determine its performance and limitations. Device performance was tested with different dilutions of healthy donor blood samples mixed with 30 micron particles simulating CTCs. The results obtained from these experiments show very good CTC recovery of up to 100% and the depletion of blood cellular components is around 99.9%. (Author)

  3. Severe hypoxia induces chemo-resistance in clinical cervical tumors through MVP over-expression.

    Science.gov (United States)

    Lara, Pedro C; Lloret, Marta; Clavo, Bernardino; Apolinario, Rosa M; Henríquez-Hernández, Luis Alberto; Bordón, Elisa; Fontes, Fausto; Rey, Agustín

    2009-08-06

    Oxygen molecule modulates tumour response to radiotherapy. Higher radiation doses are required under hypoxic conditions to induce cell death. Hypoxia may inhibit the non-homologous end-joining DNA repair through down regulating Ku70/80 expression. Hypoxia induces drug resistance in clinical tumours, although the mechanism is not clearly elucidated. Vaults are ribonucleoprotein particles with a hollow barrel-like structure composed of three proteins: major vault protein (MVP), vault poly(ADP-ribose) polymerase, and telomerase associated protein-1 and small untranslated RNA. Over-expression of MVP has been associated with chemotherapy resistance. Also, it has been related to poor outcome in patients treated with radiotherapy alone. The aim of the present study was to assess the relation of Major Vault Protein expression and tumor hypoxia in clinical cervical tumors. MVP, p53 and angiogenesis, together with tumor oxygenation, were determined in forty-three consecutive patients suffering from localized cervix carcinoma. High MVP expression was related to severe hypoxia compared to low MVP expressing tumors (p = 0.022). Tumors over-expressing MVP also showed increased angiogenesis (p = 0.003). Besides it, in this study we show for the first time that severe tumor hypoxia is associated with high MVP expression in clinical cervical tumors. Up-regulation of MVP by hypoxia is of critical relevance as chemotherapy is currently a standard treatment for those patients. From our results it could be suggested that hypoxia not only induces increased genetic instability, oncogenic properties and metastatization, but through the correlation observed with MVP expression, another pathway of chemo and radiation resistance could be developed.

  4. Severe hypoxia induces chemo-resistance in clinical cervical tumors through MVP over-expression

    International Nuclear Information System (INIS)

    Lara, Pedro C; Lloret, Marta; Clavo, Bernardino; Apolinario, Rosa M; Henríquez-Hernández, Luis Alberto; Bordón, Elisa; Fontes, Fausto; Rey, Agustín

    2009-01-01

    Oxygen molecule modulates tumour response to radiotherapy. Higher radiation doses are required under hypoxic conditions to induce cell death. Hypoxia may inhibit the non-homologous end-joining DNA repair through down regulating Ku70/80 expression. Hypoxia induces drug resistance in clinical tumours, although the mechanism is not clearly elucidated. Vaults are ribonucleoprotein particles with a hollow barrel-like structure composed of three proteins: major vault protein (MVP), vault poly(ADP-ribose) polymerase, and telomerase associated protein-1 and small untranslated RNA. Over-expression of MVP has been associated with chemotherapy resistance. Also, it has been related to poor outcome in patients treated with radiotherapy alone. The aim of the present study was to assess the relation of Major Vault Protein expression and tumor hypoxia in clinical cervical tumors. MVP, p53 and angiogenesis, together with tumor oxygenation, were determined in forty-three consecutive patients suffering from localized cervix carcinoma. High MVP expression was related to severe hypoxia compared to low MVP expressing tumors (p = 0.022). Tumors over-expressing MVP also showed increased angiogenesis (p = 0.003). Besides it, in this study we show for the first time that severe tumor hypoxia is associated with high MVP expression in clinical cervical tumors. Up-regulation of MVP by hypoxia is of critical relevance as chemotherapy is currently a standard treatment for those patients. From our results it could be suggested that hypoxia not only induces increased genetic instability, oncogenic properties and metastatization, but through the correlation observed with MVP expression, another pathway of chemo and radiation resistance could be developed

  5. Chemo-radioresistance of small cell lung cancer cell lines derived from untreated primary tumors obtained by diagnostic bronchofiberscopy

    International Nuclear Information System (INIS)

    Tanio, Yoshiro; Watanabe, Masatoshi; Inoue, Tamotsu

    1990-01-01

    New cell lines of small cell lung cancer (SCLC) were established from specimens of untreated primary tumors biopsied by diagnostic bronchofiberscopy. The advantage of this method was ease of obtaining specimens from lung tumors. Establishment of cell lines was successful with 4 of 13 specimens (30%). Clinical responses of the tumors showed considerable variation, but were well correlated with the in vitro sensitivity of the respective cell lines to chemotherapeutic drugs and irradiation. One of the cell lines was resistant to all drugs tested and irradiation, while another was sensitive to all of them. Although the acquired resistance of SCLC is the biggest problem in treatment, the natural resistance to therapy is another significant problem. Either acquired or natural, resistance mechanisms of SCLC may be elucidated by the use of such cell lines derived from untreated tumors. This method and these SCLC cell lines are expected to be useful for the serial study of biologic and genetic changes of untreated and pre-treated tumors, or primary and secondary tumors. (author)

  6. Adoptively transferred immune T cells eradicate established tumors in spite of cancer-induced immune suppression

    Science.gov (United States)

    Arina, Ainhoa; Schreiber, Karin; Binder, David C.; Karrison, Theodore; Liu, Rebecca B.; Schreiber, Hans

    2014-01-01

    Myeloid-derived CD11b+Gr1+ suppressor cells (MDSC) and tumor-associated macrophages (TAM) are considered a major obstacle for effective adoptive T cell therapy. Myeloid cells suppress naive T cell proliferation ex vivo and can prevent the generation of T cell responses in vivo. We find, however, that immune T cells adoptively transferred eradicate well-established tumors in the presence of MDSC and TAM which are strongly immunosuppressive ex vivo. These MDSC and TAM were comparable in levels and immunosuppression among different tumor models. Longitudinal microscopy of tumors in vivo revealed that after T cell transfer tumor vasculature and cancer cells disappeared simultaneously. During T-cell mediated tumor destruction, the tumor stroma contained abundant myeloid cells (mainly TAM) that retained their suppressive properties. Preimmunized but not naive mice resisted immune suppression caused by an unrelated tumor-burden supporting the idea that in vivo, myeloid immunosuppressive cells can suppress naive but not memory T cell responses. PMID:24367029

  7. Preparation and characterization of platinum(II) and (IV) complexes of 1,3-diaminepropane and 1,4-diaminebutane: circumvention of cisplatin resistance and DNA interstrand cross-link formation in CH1cisR ovarian tumor cells.

    Science.gov (United States)

    Alvarez-Valdés, Amparo; Pérez, José Manuel; López-Solera, Isabel; Lannegrand, Raúl; Continente, José Manuel; Amo-Ochoa, Pilar; Camazón, María José; Solans, Xavier; Font-Bardía, Mercè; Navarro-Ranninger, Carmen

    2002-04-25

    The reaction of Pt(dimethyl sulfoxide)(2)CBDCA (CBDCA = 1,1-cyclobutanedicarboxylate) with 1,4-diaminebutane and 1,3-diaminepropane ligands yields, under certain conditions, new [Pt(diamine)(2)]CBDCA complexes (1a,b), where the CBDCA ligand has been removed from the coordination sphere of the platinum atom by the diamine ligand, instead of forming the expected [Pt(diamine)CBDCA] complexes (1'a,b). The structure of complexes 1a and 1'b was solved by X-ray diffraction. Complex 1a crystallizes in the orthorhombic system, in the noncentrosymmetric C222 space group, with unit cell parameters: a = 20.053(2) A; b = 8.655(2) A, c = 5.711(3) A; V = 991.2(6) A(3); delta (calcd) = 1.627 mg/m(3); and R = 0.050. The Pt atom displays an unexpected distorted tetrahedral coordination with a N-Pt-N inner bond angle equal to 81(2) degrees for N atoms of the same 1,3-propanediamine ligand and a N-Pt-N bond angle for different ligands equal to 135.4(9) degrees. Complex 1'b crystallizes in the monoclinic system, in the centrosymmetric P2(1)/c space group, with unit cell parameters: a = 6.007(2) A; b = 15.336(4) A, c = 13.232(5) A; beta = 101.90(3) degrees; V = 1192.8(7) A(3); delta (calcd) = 2.369 mg/m(3); and R = 0.067. Cytotoxicity data show that of all the synthesized compounds, only complexes 1'a and 1'b exhibit remarkable cytotoxic properties. Thus, in contrast with carboplatin (cis-diammine-1,1-cyclobutane dicarboxilatoplatinum(II)), compounds 1'a and 1'b, which also contain the CBDCA ligand, are able to circumvent cisplatin (cis-diamminedichloroplatinum(II)) resistance in several tumor cells. Moreover, after 24 h of incubation of CH1cisR ovarian tumor cells with 10 microM of compounds 1'a and 1'b, the level of DNA interstrand cross-links (ICLs) induced by compounds 1'a and 1'b is 3.3 and 3.8 times higher, respectively, than that of carboplatin and 3.5 and 4.0 times higher, respectively, than that of cisplatin. Interestingly, under the same conditions, the intracellular

  8. Molecular mechanisms of drug resistance and tumor promotion involving mammalian ribonucleotide reductase

    Energy Technology Data Exchange (ETDEWEB)

    Choy, B.B.K.

    1991-01-01

    Mammalian ribonucleotide reductase is a highly regulated, rate-limiting activity responsible for converting ribonucleoside diphosphates to the deoxyribonucleotide precursors of DNA. The enzyme consists of two nonidentical proteins called M1 and M2, both of which are required for activity. Hydroxyurea is an antitumor agent which inhibits ribonucleotide reductase by interacting with the M2 component specifically at a unique tyrosyl free radical. Studies were conducted on a series of drug resistant mouse cell lines, selected by a step-wise procedure for increasing levels of resistance to the cytotoxic effects of hydroxyurea. Each successive drug selection step leading to the isolation of highly resistant cells was accompanied by stable elevations in cellular resistance and ribonucleotide reductase activity. The drug resistant cell lines exhibited gene amplification of the M2 gene, elevated M2 mRNA, and M2 protein. In addition to M2 gene amplification, posttranscriptional modulation also occurred during the drug selection. Studies of the biosynthesis rates with exogenously added iron suggest a role for iron in regulating the level of M2 protein when cells are cultured in the presence of hydroxyurea. The hydroxyurea-inactivated ribonucleotide reductase protein M2 has a destabilized iron centre, which readily releases iron. Altered expression of ferritin appears to be required for the development of hydroxyurea resistance in nammalian cells. The results show an interesting relationship between the expressions of ribonucleotide reductase and ferritin. The phorbol ester tumor promoter, TPA, is also able to alter the expression of M2. TPA was able to induce M2 mRNA levels transiently up to 18-fold within 1/2 hour. This rapid and large elevation of ribonucleotide reductase suggests that the enzyme may play a role in tumor promotion. Studies of the M2 promoter region were undertaken to better understand the mechanism of TPA induction of M2.

  9. Intravital imaging of cancer stem cell plasticity in mammary tumors

    NARCIS (Netherlands)

    Zomer, A.; Ellenbroek, S.I.; Ritsma, L.; Beerling, E.; Vrisekoop, N.; van Rheenen, J.

    2013-01-01

    It is widely debated whether all tumor cells in mammary tumors have the same potential to propagate and maintain tumor growth or whether there is a hierarchical organization. Evidence for the latter theory is mainly based on the ability or failure of transplanted tumor cells to produce detectable

  10. Trading in your spindles for blebs: the amoeboid tumor cell phenotype in prostate cancer

    Directory of Open Access Journals (Sweden)

    Samantha Morley

    2014-08-01

    Full Text Available Prostate cancer (PCa remains a principal cause of mortality in developed countries. Because no clinical interventions overcome resistance to androgen ablation therapy, management of castration resistance and metastatic disease remains largely untreatable. Metastasis is a multistep process in which tumor cells lose cell-cell contacts, egress from the primary tumor, intravasate, survive shear stress within the vasculature and extravasate into tissues to colonize ectopic sites. Tumor cells reestablish migratory behaviors employed during nonneoplastic processes such as embryonic development, leukocyte trafficking and wound healing. While mesenchymal motility is an established paradigm of dissemination, an alternate, 'amoeboid' phenotype is increasingly appreciated as relevant to human cancer. Here we discuss characteristics and pathways underlying the phenotype, and highlight our findings that the cytoskeletal regulator DIAPH3 governs the mesenchymal-amoeboid transition. We also describe our identification of a new class of tumor-derived microvesicles, large oncosomes, produced by amoeboid cells and with potential clinical utility in prostate and other cancers.

  11. In Vitro Efficient Expansion of Tumor Cells Deriving from Different Types of Human Tumor Samples

    Directory of Open Access Journals (Sweden)

    Ilaria Turin

    2014-03-01

    Full Text Available Obtaining human tumor cell lines from fresh tumors is essential to advance our understanding of antitumor immune surveillance mechanisms and to develop new ex vivo strategies to generate an efficient anti-tumor response. The present study delineates a simple and rapid method for efficiently establishing primary cultures starting from tumor samples of different types, while maintaining the immuno-histochemical characteristics of the original tumor. We compared two different strategies to disaggregate tumor specimens. After short or long term in vitro expansion, cells analyzed for the presence of malignant cells demonstrated their neoplastic origin. Considering that tumor cells may be isolated in a closed system with high efficiency, we propose this methodology for the ex vivo expansion of tumor cells to be used to evaluate suitable new drugs or to generate tumor-specific cytotoxic T lymphocytes or vaccines.

  12. Endogenous markers of tumor hypoxia. Predictors of clinical radiation resistance?

    International Nuclear Information System (INIS)

    Vordermark, D.; Brown, J.M.

    2003-01-01

    Background: Eppendorf electrode measurements of tumor oxygenation have defined an adverse effect of tumor hypoxia on prognosis after radiotherapy and other treatment modalities, in particular in head and neck and cervix carcinomas as well as soft tissue sarcomas. Recently, the immunohistochemical detection of proteins involved in the ''hypoxic response'' of tumor cells has been discussed as a method to estimate hypoxia in clinical tumor specimens. Material and Methods: This review focuses on clinical and experimental data, regarding prognostic impact and comparability with other methods of hypoxia detection, for three proteins suggested as endogenous markers of tumor hypoxia: hypoxia-inducible factor-1α (HIF-1α), carbonic anhydrase 9 (CA 9), and glucose transporter 1 (GLUT1). Results: None of the three potential hypoxia markers is exclusively hypoxia-specific, and in each case protein can be detected under normoxic conditions in vitro. HIF-1α responds rapidly to hypoxia but also to reoxygenation, making this marker quite unstable in the context of clinical sample collection. The perinecrotic labeling pattern typical of chronic hypoxia and a reasonable agreement with injectable hypoxia markers such as pimonidazole have most consistently been described for CA 9. All three markers showed correlation with Eppendorf electrode measurements of tumor oxygenation in carcinoma of the cervix. In nine of 13 reports, among them all three that refer to curative radiotherapy for head and neck cancer, HIF-1α overexpression was associated with poor outcome. CA 9 was an adverse prognostic factor in cervix, head and neck and lung cancer, but not in two other head and neck cancer reports. GLUT1 predicted for poor survival in colorectal, cervix and lung cancer. Conclusion: Endogenous markers have the potential to indicate therapeutically relevant levels of hypoxia within tumors. Clinical trials assessing a marker's ability to predict a benefit from specific hypoxia

  13. Engineered Breast Cancer Cell Spheroids Reproduce Biologic Properties of Solid Tumors.

    Science.gov (United States)

    Ham, Stephanie L; Joshi, Ramila; Luker, Gary D; Tavana, Hossein

    2016-11-01

    Solid tumors develop as 3D tissue constructs. As tumors grow larger, spatial gradients of nutrients and oxygen and inadequate diffusive supply to cells distant from vasculature develops. Hypoxia initiates signaling and transcriptional alterations to promote survival of cancer cells and generation of cancer stem cells (CSCs) that have self-renewal and tumor-initiation capabilities. Both hypoxia and CSCs are associated with resistance to therapies and tumor relapse. This study demonstrates that 3D cancer cell models, known as tumor spheroids, generated with a polymeric aqueous two-phase system (ATPS) technology capture these important biological processes. Similar to solid tumors, spheroids of triple negative breast cancer cells deposit major extracellular matrix proteins. The molecular analysis establishes presence of hypoxic cells in the core region and expression of CSC gene and protein markers including CD24, CD133, and Nanog. Importantly, these spheroids resist treatment with chemotherapy drugs. A combination treatment approach using a hypoxia-activated prodrug, TH-302, and a chemotherapy drug, doxorubicin, successfully targets drug resistant spheroids. This study demonstrates that ATPS spheroids recapitulate important biological and functional properties of solid tumors and provide a unique model for studies in cancer research. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. HAMLET (human alpha-lactalbumin made lethal to tumor cells) triggers autophagic tumor cell death.

    Science.gov (United States)

    Aits, Sonja; Gustafsson, Lotta; Hallgren, Oskar; Brest, Patrick; Gustafsson, Mattias; Trulsson, Maria; Mossberg, Ann-Kristin; Simon, Hans-Uwe; Mograbi, Baharia; Svanborg, Catharina

    2009-03-01

    HAMLET, a complex of partially unfolded alpha-lactalbumin and oleic acid, kills a wide range of tumor cells. Here we propose that HAMLET causes macroautophagy in tumor cells and that this contributes to their death. Cell death was accompanied by mitochondrial damage and a reduction in the level of active mTOR and HAMLET triggered extensive cytoplasmic vacuolization and the formation of double-membrane-enclosed vesicles typical of macroautophagy. In addition, HAMLET caused a change from uniform (LC3-I) to granular (LC3-II) staining in LC3-GFP-transfected cells reflecting LC3 translocation during macroautophagy, and this was blocked by the macroautophagy inhibitor 3-methyladenine. HAMLET also caused accumulation of LC3-II detected by Western blot when lysosomal degradation was inhibited suggesting that HAMLET caused an increase in autophagic flux. To determine if macroautophagy contributed to cell death, we used RNA interference against Beclin-1 and Atg5. Suppression of Beclin-1 and Atg5 improved the survival of HAMLET-treated tumor cells and inhibited the increase in granular LC3-GFP staining. The results show that HAMLET triggers macroautophagy in tumor cells and suggest that macroautophagy contributes to HAMLET-induced tumor cell death.

  15. Tumor associated macrophages protect colon cancer cells from TRAIL-induced apoptosis through IL-1beta-dependent stabilization of Snail in tumor cells.

    Directory of Open Access Journals (Sweden)

    Pawan Kaler

    2010-07-01

    Full Text Available We recently reported that colon tumor cells stimulate macrophages to release IL-1beta, which in turn inactivates GSK3beta and enhances Wnt signaling in colon cancer cells, generating a self-amplifying loop that promotes the growth of tumor cells.Here we describe that macrophages protect HCT116 and Hke-3 colon cancer cells from TRAIL-induced apoptosis. Inactivation of IL-1beta by neutralizing IL-1beta antibody, or silencing of IL-1beta in macrophages inhibited their ability to counter TRAIL-induced apoptosis. Accordingly, IL-1beta was sufficient to inhibit TRAIL-induced apoptosis. TRAIL-induced collapse of the mitochondrial membrane potential (Delta psi and activation of caspases were prevented by macrophages or by recombinant IL-1beta. Pharmacological inhibition of IL-1beta release from macrophages by vitamin D(3, a potent chemopreventive agent for colorectal cancer, restored the ability of TRAIL to induce apoptosis of tumor cells cultured with macrophages. Macrophages and IL-1beta failed to inhibit TRAIL-induced apoptosis in HCT116 cells expressing dnIkappaB, dnAKT or dnTCF4, confirming that they oppose TRAIL-induced cell death through induction of Wnt signaling in tumor cells. We showed that macrophages and IL-1beta stabilized Snail in tumor cells in an NF-kappaB/Wnt dependent manner and that Snail deficient tumor cells were not protected from TRAIL-induced apoptosis by macrophages or by IL-1beta, demonstrating a crucial role of Snail in the resistance of tumor cells to TRAIL.We have identified a positive feedback loop between tumor cells and macrophages that propagates the growth and promotes the survival of colon cancer cells: tumor cells stimulate macrophages to secrete IL-1beta, which in turn, promotes Wnt signaling and stabilizes Snail in tumor cells, conferring resistance to TRAIL. Vitamin D(3 halts this amplifying loop by interfering with the release of IL-1beta from macrophages. Accordingly, vitamin D(3 sensitizes tumor cells to TRAIL

  16. Cells competition in tumor growth poroelasticity

    Science.gov (United States)

    Fraldi, Massimiliano; Carotenuto, Angelo R.

    2018-03-01

    Growth of biological tissues has been recently treated within the framework of Continuum Mechanics, by adopting heterogeneous poroelastic models where the interaction between soft matrix and interstitial fluid flow is coupled with inelastic effects ad hoc introduced to simulate the macroscopic volumetric growth determined by cells division, cells growth and extracellular matrix changes occurring at the micro-scale level. These continuum models seem to overcome some limitations intrinsically associated to other alternative approaches based on mass balances in multiphase systems, because the crucial role played by residual stresses accompanying growth and nutrients walkway is preserved. Nevertheless, when these strategies are applied to analyze solid tumors, mass growth is usually assigned in a prescribed form that essentially copies the in vitro measured intrinsic growth rates of the cell species. As a consequence, some important cell-cell dynamics governing mass evolution and invasion rates of cancer cells, as well as their coupling with feedback mechanisms associated to in situ stresses, are inevitably lost and thus the spatial distribution and the evolution with time of the growth inside the tumor -which would be results rather than inputs- are forced to enter in the model simply as data. In order to solve this paradox, it is here proposed an enhanced multi-scale poroelastic model undergoing large deformations and embodying inelastic growth, where the net growth terms directly result from the "interspecific" predator-prey (Volterra/Lotka-like) competition occurring at the micro-scale level between healthy and abnormal cell species. In this way, a system of fully-coupled non-linear PDEs is derived to describe how the fight among cell species to grab the available common resources, stress field, pressure gradients, interstitial fluid flows driving nutrients and inhomogeneous growth all simultaneously interact to decide the tumor fate.

  17. Are Breast Tumor Stem Cells Responsible for Metastasis and Angiogenesis?

    National Research Council Canada - National Science Library

    Pan, Quintin

    2005-01-01

    .... The current dogma of metastasis is that most primary tumor cells have low metastatic potential, but rare cells, less than one in ten million, within large primary tumors acquire metastatic capacity...

  18. Granular cell tumors of the urinary bladder

    Directory of Open Access Journals (Sweden)

    Kayani Naila

    2007-03-01

    Full Text Available Abstract Background Granular cell tumors (GCTs are extremely rare lesions of the urinary bladder with only nine cases being reported in world literature of which one was malignant. Generally believed to be of neural origin based on histochemical, immunohistochemical, and ultrastructural studies; they mostly follow a clinically benign course but are commonly mistaken for malignant tumors since they are solid looking, ulcerated tumors with ill-defined margins. Materials and methods We herein report two cases of GCTs, one benign and one malignant, presenting with gross hematuria in a 14- and a 47-year-old female, respectively. Results Histopathology revealed characteristic GCTs with positive immunostaining for neural marker (S-100 and negative immunostaining for epithelial (cytokeratin, Cam 5.2, AE/A13, neuroendocrine (neuron specific enolase, chromogranin A, and synaptophysin and sarcoma (desmin, vimentin markers. The benign tumor was successfully managed conservatively with transurethral resection alone while for the malignant tumor, radical cystectomy, hysterectomy with bilateral salpingo-oophorectomy, anterior vaginectomy, plus lymph node dissection was done. Both cases show long-term disease free survival. Conclusion We recommend careful pathologic assessment for establishing the appropriate diagnosis and either a conservative or aggressive surgical treatment for benign or localized malignant GCT of the urinary bladder, respectively.

  19. Does Royal jelly affect tumor cells?

    Directory of Open Access Journals (Sweden)

    Shirzad Maryam

    2013-04-01

    Full Text Available Introduction: Royal jelly is a substance that appears to be effective on immune system and it appears to be effective on both prevention and growth of cancer cells. In this study, we aimed to carry out a research to investigate the effect of royal jelly on the growth of WEHI-164 fibrosarcoma cell in syngenic Balb/c mice. Methods: In an experimental study, 28 male Balb/c mice were designated into four equal groups. The mice were subcutaneously injected with 5x105 WEHI-164 tumor cells on the day zero in the chest area of the animal. Animals in groups 1 to 4 were orally given 100, 200, 300 mg/kg of royal jelly or vehicle, respectively. In every individual mouse, the tumour size was measured every 2 days from day 5 (days 5, 7, 9, 11, 13, 15 and 17. Data were statistically analyzed using Kruskal-Wallis and Mann Whitney-U tests. Result: Our results showed that the mean size of tumor in case group was significantly smaller than the control group in days 11, 13, 15 and 17 (P<0.05. No metastasis was seen in test and control groups. Conclusion: With emphasize on antitumor effect of royal jelly, it seems that royal jelly has important role in control and regression of fibrosarcoma cells. Since royal jelly showed a delayed effect in control of fibrosarcoma, we suggest that royal jelly be used at least 10 days before tumor inoculation.

  20. Ovarian tumor-initiating cells display a flexible metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Angela S. [Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA (United States); Roberts, Paul C. [Biomedical Science and Pathobiology, Virginia Tech, Blacksburg, VA (United States); Frisard, Madlyn I. [Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA (United States); Hulver, Matthew W., E-mail: hulvermw@vt.edu [Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA (United States); Schmelz, Eva M., E-mail: eschmelz@vt.edu [Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA (United States)

    2014-10-15

    An altered metabolism during ovarian cancer progression allows for increased macromolecular synthesis and unrestrained growth. However, the metabolic phenotype of cancer stem or tumor-initiating cells, small tumor cell populations that are able to recapitulate the original tumor, has not been well characterized. In the present study, we compared the metabolic phenotype of the stem cell enriched cell variant, MOSE-L{sub FFLv} (TIC), derived from mouse ovarian surface epithelial (MOSE) cells, to their parental (MOSE-L) and benign precursor (MOSE-E) cells. TICs exhibit a decrease in glucose and fatty acid oxidation with a concomitant increase in lactate secretion. In contrast to MOSE-L cells, TICs can increase their rate of glycolysis to overcome the inhibition of ATP synthase by oligomycin and can increase their oxygen consumption rate to maintain proton motive force when uncoupled, similar to the benign MOSE-E cells. TICs have an increased survival rate under limiting conditions as well as an increased survival rate when treated with AICAR, but exhibit a higher sensitivity to metformin than MOSE-E and MOSE-L cells. Together, our data show that TICs have a distinct metabolic profile that may render them flexible to adapt to the specific conditions of their microenvironment. By better understanding their metabolic phenotype and external environmental conditions that support their survival, treatment interventions can be designed to extend current therapy regimens to eradicate TICs. - Highlights: • Ovarian cancer TICs exhibit a decreased glucose and fatty acid oxidation. • TICs are more glycolytic and have highly active mitochondria. • TICs are more resistant to AICAR but not metformin. • A flexible metabolism allows TICs to adapt to their microenvironment. • This flexibility requires development of specific drugs targeting TIC-specific changes to prevent recurrent TIC outgrowth.

  1. Ovarian tumor-initiating cells display a flexible metabolism

    International Nuclear Information System (INIS)

    Anderson, Angela S.; Roberts, Paul C.; Frisard, Madlyn I.; Hulver, Matthew W.; Schmelz, Eva M.

    2014-01-01

    An altered metabolism during ovarian cancer progression allows for increased macromolecular synthesis and unrestrained growth. However, the metabolic phenotype of cancer stem or tumor-initiating cells, small tumor cell populations that are able to recapitulate the original tumor, has not been well characterized. In the present study, we compared the metabolic phenotype of the stem cell enriched cell variant, MOSE-L FFLv (TIC), derived from mouse ovarian surface epithelial (MOSE) cells, to their parental (MOSE-L) and benign precursor (MOSE-E) cells. TICs exhibit a decrease in glucose and fatty acid oxidation with a concomitant increase in lactate secretion. In contrast to MOSE-L cells, TICs can increase their rate of glycolysis to overcome the inhibition of ATP synthase by oligomycin and can increase their oxygen consumption rate to maintain proton motive force when uncoupled, similar to the benign MOSE-E cells. TICs have an increased survival rate under limiting conditions as well as an increased survival rate when treated with AICAR, but exhibit a higher sensitivity to metformin than MOSE-E and MOSE-L cells. Together, our data show that TICs have a distinct metabolic profile that may render them flexible to adapt to the specific conditions of their microenvironment. By better understanding their metabolic phenotype and external environmental conditions that support their survival, treatment interventions can be designed to extend current therapy regimens to eradicate TICs. - Highlights: • Ovarian cancer TICs exhibit a decreased glucose and fatty acid oxidation. • TICs are more glycolytic and have highly active mitochondria. • TICs are more resistant to AICAR but not metformin. • A flexible metabolism allows TICs to adapt to their microenvironment. • This flexibility requires development of specific drugs targeting TIC-specific changes to prevent recurrent TIC outgrowth

  2. Cisplatin-induced Casepase-3 activation in different tumor cells

    Science.gov (United States)

    Shi, Hua; Li, Xiao; Su, Ting; Zhang, Yu-Hai

    2008-12-01

    Apoptosis plays an essential role in normal organism development which is one of the main types of programmed cell death to help tissues maintain homeostasis. Defective apoptosis can result in cell accumulation and therefore effects on tumor pathogenesis, progression and therapy resistance. A family of proteins, known as caspases, is typically activated in the early stages of apoptosis. Therefore, studying the kinetics of activation of caspases induced by antitumor drugs can contribute to antitumor drug discovery and explanation of the molecular mechanisms. This paper detected the Caspase-3 activity induced by cisplatin in human adenoid cystic carcinoma cell line (ACC-M), human hepatocellular liver carcinoma cell line (HepG2) and human epithelial carcinoma cell line (Hela) with stably expressing ECFP-DEVDDsRed (CD3) probe, a fluorescent probe consisting of Enhanced Cyan Fluorescent Protein (ECFP), red fluorescent protein (DsRed) and a linker with a recognition site of Caspase-3, by using the capillary electrophoresis (CE) and fluorescence resonance energy transfer (FRET) imaging system. Under the same concentration of cisplatin, ACC-M cells responded the most rapidly, and then HepG2 cells and Hela cells, respectively, in the early 30 hours. Later, HepG2 cells represented acceleration in the Caspase-3 activation speed and reached full activation the earliest comparing to other two cell types. The results demonstrated that ACC-M cell is more sensitive than the other two cell types under the treatment of cisplatin.

  3. Oxygen microenvironment affects the uptake of nanoparticles in head and neck tumor cells

    Science.gov (United States)

    Chen, Eunice Y.; Hodge, Sasson; Tai, Katherine; Hou, Huagang; Khan, Nadeem; Hoopes, P. Jack; Samkoe, Kimberley S.

    2013-02-01

    Survival of head and neck cancer patients has not improved in several decades despite advances in diagnostic and therapeutic techniques. Tumor hypoxia in head and neck cancers is a critical factor that leads to poor prognosis, resistance to radiation and chemotherapies, and increased metastatic potential. Magnetic nanoparticle hyperthermia (mNPHT) is a promising therapy for hypoxic tumors because nanoparticles (NP) can be directly injected into, or targeted to, hypoxic tumor cells and exposed to alternating magnetic fields (AMF) to induce hyperthermia. Magnetic NPHT can improve therapeutic effectiveness by two modes of action: 1) direct killing of hypoxic tumor cells; and 2) increase in tumor oxygenation, which has the potential to make the tumor more susceptible to adjuvant therapies such as radiation and chemotherapy. Prior studies in breast cancer cells demonstrated that a hypoxic microenvironment diminished NP uptake in vitro; however, mNPHT with intratumoral NP injection in hypoxic tumors increased tumor oxygenation and delayed tumor growth. In this study, head and neck squamous cell carcinoma (HNSCC) cell lines were incubated in normoxic, hypoxic, and hyperoxic conditions with iron oxide NP for 4-72 hours. After incubation, the cells were analyzed for iron uptake by mass spectrometry, Prussian blue staining, and electron microscopy. In contrast to breast cancer cells, uptake of NPs was increased in hypoxic microenvironments as compared to normoxic conditions in HNSCC cells. In future studies, we will confirm the effect of the oxygen microenvironment on NP uptake and efficacy of mNPHT both in vitro and in vivo.

  4. Colorectal cancer: genetic abnormalities, tumor progression, tumor heterogeneity, clonal evolution and tumor-initiating cells.

    Science.gov (United States)

    Testa, Ugo; Pelosi, Elvira; Castelli, Germana

    2018-04-13

    Colon cancer is the third most common cancer worldwide. Most colorectal cancer occurrences are sporadic, not related to genetic predisposition or family history; however, 20-30% of patients with colorectal cancer have a family history of colorectal cancer and 5% of these tumors arise in the setting of a Mendelian inheritance syndrome. In many patients, the development of a colorectal cancer is preceded by a benign neoplastic lesion: either an adenomatous polyp or a serrated polyp. Studies carried out in the last years have characterized the main molecular alterations occurring in colorectal cancers, showing that the tumor of each patient displays from two to eight driver mutations. The ensemble of molecular studies, including gene expression studies, has led to two proposed classifications of colorectal cancers, with the identification of four/five non-overlapping groups. The homeostasis of the rapidly renewing intestinal epithelium is ensured by few stem cells present at the level of the base of intestinal crypts. Various experimental evidence suggests that colorectal cancers may derive from the malignant transformation of intestinal stem cells or of intestinal cells that acquire stem cell properties following malignant transformation. Colon cancer stem cells seem to be involved in tumor chemoresistance, radioresistance and relapse.

  5. Maximum recovery potential of human tumor cells may predict clinical outcome in radiotherapy

    International Nuclear Information System (INIS)

    Weichselbaum, R.R.; Beckett, M.

    1987-01-01

    We studied inherent radiosensitivity/resistance (D0), ability to accumulate sublethal damage (n) and repair of potentially lethal damage (PLDR) in established human tumor cell lines as well as early passage human tumor cell lines derived from patients with known outcome following radiotherapy. Survival 24 hrs after treatment of human tumor cells with X rays in plateau phase cultures is a function of initial damage (D0, n), as well as recovery over 24 hrs (PLDR). A surviving fraction greater than .1 24 hrs following treatment with 7 Gy in plateau phase cultures is associated with tumor cell types (melanoma, osteosarcoma) with a high probability of radiotherapy failure or tumor cells derived from patients who actually failed radiotherapy. Therefore, total cellular recovery following radiation may be an important determinant of radiocurability. Accurate assays of radiotherapy outcome may need to account for all these radiobiological parameters

  6. Establishment and Characterization of a Tumor Stem Cell-Based Glioblastoma Invasion Model

    DEFF Research Database (Denmark)

    Jensen, Stine Skov; Meyer, Morten; Petterson, Stine Asferg

    2016-01-01

    AIMS: Glioblastoma is the most frequent and malignant brain tumor. Recurrence is inevitable and most likely connected to tumor invasion and presence of therapy resistant stem-like tumor cells. The aim was therefore to establish and characterize a three-dimensional in vivo-like in vitro model taking...... invasion and tumor stemness into account. METHODS: Glioblastoma stem cell-like containing spheroid (GSS) cultures derived from three different patients were established and characterized. The spheroids were implanted in vitro into rat brain slice cultures grown in stem cell medium and in vivo into brains...... of immuno-compromised mice. Invasion was followed in the slice cultures by confocal time-lapse microscopy. Using immunohistochemistry, we compared tumor cell invasion as well as expression of proliferation and stem cell markers between the models. RESULTS: We observed a pronounced invasion into brain slice...

  7. The Role of Tumor Associated Macrophage in Recurrent Growth of Tumor Stem Cell

    Science.gov (United States)

    2011-09-01

    recent cancer stem cell (CSC) theory, recurrent tumor must arise from a dormant tumor stem cell whose re-growth is triggered by shifting of...microenvironment. This project aims at clarifying the roles of TAM in recurrent growth of dormant stem cell in breast cancer. We hypothesize that the balance of...dormancy and recurrence is determined by the ability of the tumor stem cells to recruit TAM which in turn promotes self-renewal of the stem cell . We

  8. TRAIL-induced programmed necrosis as a novel approach to eliminate tumor cells

    International Nuclear Information System (INIS)

    Voigt, Susann; Kalthoff, Holger; Adam, Dieter; Philipp, Stephan; Davarnia, Parvin; Winoto-Morbach, Supandi; Röder, Christian; Arenz, Christoph; Trauzold, Anna; Kabelitz, Dieter; Schütze, Stefan

    2014-01-01

    The cytokine TRAIL represents one of the most promising candidates for the apoptotic elimination of tumor cells, either alone or in combination therapies. However, its efficacy is often limited by intrinsic or acquired resistance of tumor cells to apoptosis. Programmed necrosis is an alternative, molecularly distinct mode of programmed cell death that is elicited by TRAIL under conditions when the classical apoptosis machinery fails or is actively inhibited. The potential of TRAIL-induced programmed necrosis in tumor therapy is, however, almost completely uncharacterized. We therefore investigated its impact on a panel of tumor cell lines of wide-ranging origin. Cell death/viability was measured by flow cytometry/determination of intracellular ATP levels/crystal violet staining. Cell surface expression of TRAIL receptors was detected by flow cytometry, expression of proteins by Western blot. Ceramide levels were quantified by high-performance thin layer chromatography and densitometric analysis, clonogenic survival of cells was determined by crystal violet staining or by soft agarose cloning. TRAIL-induced programmed necrosis killed eight out of 14 tumor cell lines. Clonogenic survival was reduced in all sensitive and even one resistant cell lines tested. TRAIL synergized with chemotherapeutics in killing tumor cell lines by programmed necrosis, enhancing their effect in eight out of 10 tested tumor cell lines and in 41 out of 80 chemotherapeutic/TRAIL combinations. Susceptibility/resistance of the investigated tumor cell lines to programmed necrosis seems to primarily depend on expression of the pro-necrotic kinase RIPK3 rather than the related kinase RIPK1 or cell surface expression of TRAIL receptors. Furthermore, interference with production of the lipid ceramide protected all tested tumor cell lines. Our study provides evidence that TRAIL-induced programmed necrosis represents a feasible approach for the elimination of tumor cells, and that this treatment may

  9. Dendritic cell-tumor cell hybrids and immunotherapy

    DEFF Research Database (Denmark)

    Cathelin, Dominique; Nicolas, Alexandra; Bouchot, André

    2011-01-01

    Dendritic cells (DC) are professional antigen-presenting cells currently being used as a cellular adjuvant in cancer immunotherapy strategies. Unfortunately, DC-based vaccines have not demonstrated spectacular clinical results. DC loading with tumor antigens and DC differentiation and activation...

  10. Prognostic Importance of Circulating Tumor Cells in Nonsmall Cell ...

    African Journals Online (AJOL)

    Purpose: To investigate the prognostic value of circulating tumor cells (CTCs) and to predict the treatment response in a non-small cell lung cancer (NSCLC). Methodology: A single-center prospective study involving 93 patients with NSCLC was conducted. Blood samples were analyzed for CTC count before and after ...

  11. Circulating tumor cells: clinical validity and utility.

    Science.gov (United States)

    Cabel, Luc; Proudhon, Charlotte; Gortais, Hugo; Loirat, Delphine; Coussy, Florence; Pierga, Jean-Yves; Bidard, François-Clément

    2017-06-01

    Circulating tumor cells (CTCs) are rare tumor cells and have been investigated as diagnostic, prognostic and predictive biomarkers in many types of cancer. Although CTCs are not currently used in clinical practice, CTC studies have accumulated a high level of clinical validity, especially in breast, lung, prostate and colorectal cancers. In this review, we present an overview of the current clinical validity of CTCs in metastatic and non-metastatic disease, and the main concepts and studies investigating the clinical utility of CTCs. In particular, this review will focus on breast, lung, colorectal and prostate cancer. Three major topics concerning the clinical utility of CTC are discussed-(1) treatment based on CTCs used as liquid biopsy, (2) treatment based on CTC count or CTC variations, and (3) treatment based on CTC biomarker expression. A summary of published or ongoing phase II and III trials is also presented.

  12. Repair in Ehrlich ascites tumor cells

    International Nuclear Information System (INIS)

    Wanna-Nakamura, S.S.

    1981-01-01

    Unscheduled DNA synthesis (UDS), an indicator of excision repair, was induced in freshly drawn Ehrlich ascites tumor cells (EAT), using ionizing radiation, far ultraviolet light (254 nm) or near uv light (365 nm) in combination with 8-methoxypsoralen. UDS was scored by grain counts in autoradiographs following the incorporation of tritium-labelled thymidine. The amount of UDS after each of these agents was expressed in terms of two parameters, viz. numer of cells showing repair and the mean number of grains per nucleus. The influence of radiation dose and of the duration of radioactive thymidine incubation were also examined. To test for a possible relationship between low mitotic index and repair capability, EAT cells were incubated in buffered salt media to lower the mitotic index. Cells kept in a buffered salt solution for 7 h show a marked drop in mitotic index compared to those incubated in minimal medium containing 15% fetal calf serum (MEM + FCS). This drop in mitotic index was reversible for up to 5 h, if cells were returned to MEM + FCS. Cells incubated in MEM + FCS also showed a decrease in mitotic activity compared to freshly drawn cells. This reduced mitotic index is approximately constant for up to 24 h. With the drop in mitotic index, EAT cells also show a drop in repair compared to freshly drawn cells. The repair capability of cells incubated in buffer can be restored by returning cells to MEM + FCS

  13. Genetic instability in nerve sheath cell tumors

    DEFF Research Database (Denmark)

    Rogatto, Silvia Regina; Casartelli, Cacilda; Rainho, Claudia Aparecida

    1995-01-01

    After in vitro culture, we analyzed cytogenetically four acoustic nerve neurinomas, one intraspinal neurinoma and one neurofibroma obtainedfrom unrelated patients. Monosomy of chromosomes 22 and 16 was an abnormality common to all cases, followed in frequency by loss of chromosomes 18 (three cases...... by the presence of polyploid cells with inconsistent abnormalities, endoreduplications and telomeric associations resulting in dicentric chromosomes. It is probable that these cytogenetic abnormalities represent some kind of evolutionary advantage for the in vitro progression of nerve sheath tumors....

  14. Tumor-specific apoptotic gene targeting overcomes radiation resistance in esophageal adenocarcinoma

    International Nuclear Information System (INIS)

    Chang, Joe Y.; Zhang Xiaochun; Komaki, Ritsuko; Cheung, Rex; Fang Bingliang

    2006-01-01

    Purpose: To overcome radiation resistance in esophageal adenocarcinoma by tumor-specific apoptotic gene targeting using tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Methods and Materials: Adenoviral vector Ad/TRAIL-F/RGD with a tumor-specific human telomerase reverse transcription promoter was used to transfer TRAIL gene to human esophageal adenocarcinoma and normal human lung fibroblastic cells (NHLF). Activation of apoptosis was analyzed by Western blot, fluorescent activated cell sorting, and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate labeling (TUNEL) assay. A human esophageal adenocarcinoma mouse model was treated with intratumoral injections of Ad/TRAIL-F/RGD plus local radiotherapy. Results: The combination of Ad/TRAIL-F/RGD and radiotherapy increased the cell-killing effect in all esophageal adenocarcinoma cell lines but not in NHLF cells. This combination also significantly reduced clonogenic formation (p < 0.05) and increased sub-G1 deoxyribonucleic acid accumulation in cancer cells (p < 0.05). Activation of apoptosis by Ad/TRAIL-F/RGD plus radiotherapy was demonstrated by activation of caspase-9, caspase-8, and caspase-3 and cleaved poly (adenosine diphosphate-ribose) polymerase in vitro and TUNEL assay in vivo. Combined Ad/TRAIL-F/RGD and radiotherapy dramatically inhibited tumor growth and prolonged mean survival in the esophageal adenocarcinoma model to 31.6 days from 16.7 days for radiotherapy alone and 21.5 days for Ad/TRAIL-F/RGD alone (p < 0.05). Conclusions: The combination of tumor-specific TRAIL gene targeting and radiotherapy enhances the effect of suppressing esophageal adenocarcinoma growth and prolonging survival

  15. Mast cells: potential positive and negative roles in tumor biology.

    Science.gov (United States)

    Marichal, Thomas; Tsai, Mindy; Galli, Stephen J

    2013-11-01

    Mast cells are immune cells that reside in virtually all vascularized tissues. Upon activation by diverse mechanisms, mast cells can secrete a broad array of biologically active products that either are stored in the cytoplasmic granules of the cells (e.g., histamine, heparin, various proteases) or are produced de novo upon cell stimulation (e.g., prostaglandins, leukotrienes, cytokines, chemokines, and growth factors). Mast cells are best known for their effector functions during anaphylaxis and acute IgE-associated allergic reactions, but they also have been implicated in a wide variety of processes that maintain health or contribute to disease. There has been particular interest in the possible roles of mast cells in tumor biology. In vitro studies have shown that mast cells have the potential to influence many aspects of tumor biology, including tumor development, tumor-induced angiogenesis, and tissue remodeling, and the shaping of adaptive immune responses to tumors. Yet, the actual contributions of mast cells to tumor biology in vivo remain controversial. Here, we review some basic features of mast cell biology with a special emphasis on those relevant to their potential roles in tumors. We discuss how using in vivo tumor models in combination with models in which mast cell function can be modulated has implicated mast cells in the regulation of host responses to tumors. Finally, we summarize data from studies of human tumors that suggest either beneficial or detrimental roles for mast cells in tumors. ©2013 AACR.

  16. Imaging Reporters for Proteasome Activity Identify Tumor- and Metastasis-Initiating Cells

    Directory of Open Access Journals (Sweden)

    Amanda C. Stacer

    2015-08-01

    Full Text Available Tumor-initiating cells, also designated as cancer stem cells, are proposed to constitute a subpopulation of malignant cells central to tumorigenesis, metastasis, and treatment resistance. We analyzed the activity of the proteasome, the primary organelle for targeted protein degradation, as a marker of tumor- and metastasis-initiating cells. Using human and mouse breast cancer cells expressing a validated fluorescent reporter, we found a small subpopulation of cells with low proteasome activity that divided asymmetrically to produce daughter cells with low or high proteasome activity. Breast cancer cells with low proteasome activity had greater local tumor formation and metastasis in immunocompromised and immunocompetent mice. To allow flexible labeling of cells, we also developed a new proteasome substrate based on HaloTag technology. Patient-derived glioblastoma cells with low proteasome activity measured by the HaloTag reporter show key phenotypes associated with tumor-initiating cells, including expression of a stem cell transcription factor, reconstitution of the original starting population, and enhanced neurosphere formation. We also show that patient-derived glioblastoma cells with low proteasome activity have higher frequency of tumor formation in mouse xenografts. These studies support proteasome function as a tool to investigate tumor- and metastasis-initiating cancer cells and a potential biomarker for outcomes in patients with several different cancers.

  17. Chronic inhibition of tumor cell-derived VEGF enhances the malignant phenotype of colorectal cancer cells

    International Nuclear Information System (INIS)

    Yamagishi, Naoko; Teshima-Kondo, Shigetada; Masuda, Kiyoshi; Nishida, Kensei; Kuwano, Yuki; Dang, Duyen T; Dang, Long H; Nikawa, Takeshi; Rokutan, Kazuhito

    2013-01-01

    Vascular endothelial growth factor-a (VEGF)-targeted therapies have become an important treatment for a number of human malignancies. The VEGF inhibitors are actually effective in several types of cancers, however, the benefits are transiently, and the vast majority of patients who initially respond to the therapies will develop resistance. One of possible mechanisms for the acquired resistance may be the direct effect(s) of VEGF inhibitors on tumor cells expressing VEGF receptors (VEGFR). Thus, we investigated here the direct effect of chronic VEGF inhibition on phenotype changes in human colorectal cancer (CRC) cells. To chronically inhibit cancer cell-derived VEGF, human CRC cell lines (HCT116 and RKO) were chronically exposed (2 months) to an anti-VEGF monoclonal antibody (mAb) or were disrupted the Vegf gene (VEGF-KO). Effects of VEGF family members were blocked by treatment with a VEGF receptor tyrosine kinase inhibitor (VEGFR-TKI). Hypoxia-induced apoptosis under VEGF inhibited conditions was measured by TUNEL assay. Spheroid formation ability was assessed using a 3-D spheroid cell culture system. Chronic inhibition of secreted/extracellular VEGF by an anti-VEGF mAb redundantly increased VEGF family member (PlGF, VEGFR1 and VEGFR2), induced a resistance to hypoxia-induced apoptosis, and increased spheroid formation ability. This apoptotic resistance was partially abrogated by a VEGFR-TKI, which blocked the compensate pathway consisted of VEGF family members, or by knockdown of Vegf mRNA, which inhibited intracellular function(s) of all Vegf gene products. Interestingly, chronic and complete depletion of all Vegf gene products by Vegf gene knockout further augmented these phenotypes in the compensate pathway-independent manner. These accelerated phenotypes were significantly suppressed by knockdown of hypoxia-inducible factor-1α that was up-regulated in the VEGF-KO cell lines. Our findings suggest that chronic inhibition of tumor cell-derived VEGF

  18. Expression of the MDR1 gene and P-glycoprotein in canine mast cell tumor cell lines

    OpenAIRE

    NAKAICHI, Munekazu; TAKESHITA, Yoko; OKUDA, Masaru; NAKAMOTO, Yuya; ITAMOTO, Kazuhito; UNE, Satoshi; SASAKI, Nobuo; KADOSAWA, Tsuyoshi; TAKAHASHI, Tomoko; TAURA, Yasuho

    2007-01-01

    Cellular drug resistance to antineoplastic drugs is often due to the presence of a drug efflux pump that reduces intracellular drug accumulation and chemosensitivity. P-glycoprotein (P-gp), which is encoded by the MDR1 gene, is considered to function as an ATP-driven membrane drug efflux pump and appears to play an important role in tumor cell resistance. In the present report, we assessed the expression of MDR1 by RT-PCR in three canine mast cell tumor cell lines, TiMC, CoMS and LuMC, origin...

  19. Immune response to UV-induced tumors: mediation of progressor tumor rejection by natural killer cells

    International Nuclear Information System (INIS)

    Streeter, P.R.; Fortner, G.W.

    1986-01-01

    Skin tumors induced in mice by chronic ultraviolet (UV) irradiation are highly antigenic and can induce a state of transplantation immunity in syngeneic animals. In the present study, the authors compared the in vitro cytolytic activity of splenic lymphocytes from mice immunized with either regressor or progressor UV-tumors. The results of this comparison implicated tumor-specific cytolytic T (Tc) lymphocytes in rejection of regressor UV-tumors, and revealed that immunization with the progressor UV-tumor 2237 failed to elicit detectable levels of progressor tumor-specific Tc cells even as the tumors rejected. Following in vitro resensitization of spleen cells from either regressor or progressor tumor immune animals, the authors found NK-like lymphocytes with anti-tumor activity. As the authors had not detected cells with this activity in splenic lymphocyte preparations prior to in vitro resensitization, the authors examined lymphocytes from the local tumor environment during the course of progressor tumor rejection for this activity. This analysis revealed NK lymphocytes exhibiting significant levels of cytolytic activity against UV-tumors. These results implicate NK cells as potential effector cells in the rejection of progressor UV-tumors by immune animals, and suggests that these cells may be regulated by T lymphocytes

  20. Giant Cell Tumors of the Axial Skeleton

    Directory of Open Access Journals (Sweden)

    Maurice Balke

    2012-01-01

    Full Text Available Background. We report on 19 cases of giant cell tumor of bone (GCT affecting the spine or sacrum and evaluate the outcome of different treatment modalities. Methods. Nineteen patients with GCT of the spine (=6 or sacrum (=13 have been included in this study. The mean followup was 51.6 months. Ten sacral GCT were treated by intralesional procedures of which 4 also received embolization, and 3 with irradiation only. All spinal GCT were surgically treated. Results. Two (15.4% patients with sacral and 4 (66.7% with spinal tumors had a local recurrence, two of the letter developed pulmonary metastases. One local recurrence of the spine was successfully treated by serial arterial embolization, a procedure previously described only for sacral tumors. At last followup, 9 patients had no evidence of disease, 8 had stable disease, 1 had progressive disease, 1 died due to disease. Six patients had neurological deficits. Conclusions. GCT of the axial skeleton have a high local recurrence rate. Neurological deficits are common. En-bloc spondylectomy combined with embolization is the treatment of choice. In case of inoperability, serial arterial embolization seems to be an alternative not only for sacral but also for spinal tumors.

  1. Vertebral bony tumor of giant cells

    International Nuclear Information System (INIS)

    Jaramillo Carling, Eduardo

    2005-01-01

    This is a report of a 37 years old, masculine patient, in whom a unique primary bone injury was demonstrated, located at T-11, diagnosed as a giant cells tumor (osteoclastoma). Location is described in the literature as unusual. The clinical presentation of the injury is described, as the initial radiological studies and magnetic resonance images 8 years after surgical treatment, with no neoplasic recurrences. The medical literature of these primary bone injuries and its treatment was also reviewed. Objectives: to present a patient with an unusual extramedullar tumor injury, of primary bone origin, benign, treated surgically and who has a post surgical follow-up of 8 years. Local tumor recurrence and not pulmonary metastasis was demonstrated. The medical literature of this bone pathology that affects the spine in an infrequent manner, was also reviewed, specially the related to medical, surgical and radio-therapeutic treatments. Methodology: the clinical history of the patient is described, who was successfully operated, because the expansive tumor was totally drawn out, without neurological injury; inter operating or post-operating vertebral instability was not observed or diagnosed. The patient was controlled in periodic form, with last medical checkup and of magnetic resonance 8 years after the surgery. The medical publications existing are reviewed

  2. Littoral cell angioma mimicking metastatic tumors

    Directory of Open Access Journals (Sweden)

    Szumilo Justyna

    2015-12-01

    Full Text Available Littoral cell angioma is a rare primary, vascular tumor thought to originate from the endothelial cells lining the sinuses of the splenic red pulp (the “littoral cells”. It is a benign, usually asymptomatic lesion diagnosed incidentally. Ultrasound and tomography appearance is not characteristic and histopathological examination is required. This work provides a case-study of littoral cell angioma which was seen in a 55-year-old female who complained of non-specific upper abdominal pain. Computed tomography revealed multiple hypo-attenuated splenic lesions suggestive for metastasis. A splenectomy was performed and routine microscopic examination supported by immunohistochemistry reactions with CD68, CD34 and CD31 showed littoral cell angioma.

  3. BMI-1 targeting interferes with patient-derived tumor-initiating cell survival and tumor growth in prostate cancer

    Science.gov (United States)

    Yusuff, Shamila; Davis, Stephani; Flaherty, Kathleen; Huselid, Eric; Patrizii, Michele; Jones, Daniel; Cao, Liangxian; Sydorenko, Nadiya; Moon, Young-Choon; Zhong, Hua; Medina, Daniel J.; Kerrigan, John; Stein, Mark N.; Kim, Isaac Y.; Davis, Thomas W.; DiPaola, Robert S.; Bertino, Joseph R.; Sabaawy, Hatem E.

    2016-01-01

    Purpose Current prostate cancer (PCa) management calls for identifying novel and more effective therapies. Self-renewing tumor-initiating cells (TICs) hold intrinsic therapy-resistance and account for tumor relapse and progression. As BMI-1 regulates stem cell self-renewal, impairing BMI-1 function for TICs-tailored therapies appears to be a promising approach. Experimental design We have previously developed a combined immunophenotypic and time-of-adherence assay to identify CD49bhiCD29hiCD44hi cells as human prostate TICs. We utilized this assay with patient derived prostate cancer cells and xenograft models to characterize the effects of pharmacological inhibitors of BMI-1. Results We demonstrate that in cell lines and patient-derived TICs, BMI-1 expression is upregulated and associated with stem cell-like traits. From a screened library, we identified a number of post-transcriptional small molecules that target BMI-1 in prostate TICs. Pharmacological inhibition of BMI-1 in patient-derived cells significantly decreased colony formation in vitro and attenuated tumor initiation in vivo, thereby functionally diminishing the frequency of TICs, particularly in cells resistant to proliferation- and androgen receptor (AR)-directed therapies, without toxic effects on normal tissues. Conclusions Our data offer a paradigm for targeting TICs and support the development of BMI-1-targeting therapy for a more effective PCa treatment. PMID:27307599

  4. Snail1 induces epithelial-to-mesenchymal transition and tumor initiating stem cell characteristics

    International Nuclear Information System (INIS)

    Dang, Hien; Ding, Wei; Emerson, Dow; Rountree, C Bart

    2011-01-01

    Tumor initiating stem-like cells (TISCs) are a subset of neoplastic cells that possess distinct survival mechanisms and self-renewal characteristics crucial for tumor maintenance and propagation. The induction of epithelial-mesenchymal-transition (EMT) by TGFβ has been recently linked to the acquisition of TISC characteristics in breast cancer. In HCC, a TISC and EMT phenotype correlates with a worse prognosis. In this work, our aim is to elucidate the underlying mechanism by which cells acquire tumor initiating characteristics after EMT. Gene and protein expression assays and Nanog-promoter luciferase reporter were utilized in epithelial and mesenchymal phenotype liver cancer cell lines. EMT was analyzed with migration/invasion assays. TISC characteristics were analyzed with tumor-sphere self-renewal and chemotherapy resistance assays. In vivo tumor assay was performed to investigate the role of Snail1 in tumor initiation. TGFβ induced EMT in epithelial cells through the up-regulation of Snail1 in Smad-dependent signaling. Mesenchymal liver cancer post-EMT demonstrates TISC characteristics such as tumor-sphere formation but are not resistant to cytotoxic therapy. The inhibition of Snail1 in mesenchymal cells results in decreased Nanog promoter luciferase activity and loss of self-renewal characteristics in vitro. These changes confirm the direct role of Snail1 in some TISC traits. In vivo, the down-regulation of Snail1 reduced tumor growth but was not sufficient to eliminate tumor initiation. In summary, TGFβ induces EMT and TISC characteristics through Snail1 and Nanog up-regulation. In mesenchymal cells post-EMT, Snail1 directly regulates Nanog expression, and loss of Snail1 regulates tumor growth without affecting tumor initiation

  5. Tumor-initiating CD49f cells are a hallmark of chemoresistant triple negative breast cancer.

    Science.gov (United States)

    Gomez-Miragaya, Jorge; González-Suárez, Eva

    2017-01-01

    Taxanes are mainstay treatment of triple negative breast cancer (TNBC) patients but resistance often develops. Using TNBC patient-derived orthoxenografts (PDX) we have recently discovered that a CD49f+ chemoresistant population with tumor-initiating ability is present in sensitive tumors and expands in tumors that have acquired resistance. Importantly, sensitivity to taxanes is recovered after long-term drug interruption. The characterization of this chemoresistant CD49f+ cells provides a unique opportunity to identify novel targets for the treatment of chemoresistant TNBC.

  6. Mechanisms of therapeutic resistance in cancer (stem cells with emphasis on thyroid cancer cells.

    Directory of Open Access Journals (Sweden)

    Sabine eHombach-Klonisch

    2014-03-01

    Full Text Available Tissue invasion, metastasis and therapeutic resistance to anti-cancer treatments are common and main causes of death in cancer patients. Tumor cells mount complex and still poorly understood molecular defense mechanisms to counteract and evade oxygen deprivation, nutritional restrictions as well as radio- and chemotherapeutic treatment regimens aimed at destabilizing their genomes and important cellular processes. In thyroid cancer, as in other tumors, such defense strategies include the reactivation in cancer cells of early developmental programs normally active exclusively in stem cells, the stimulation of cancer stem-like cells resident within the tumor tissue and the recruitment of bone marrow-derived progenitors into the tumor (Thomas et al., 2008;Klonisch et al., 2009;Derwahl, 2011. Metastasis and therapeutic resistance in cancer (stem cells involves the epithelial-to-mesenchymal transition- (EMT- mediated enhancement in cellular plasticity, which includes coordinated dynamic biochemical and nuclear changes (Ahmed et al., 2010. The purpose of the present review is to provide an overview of the role of DNA repair mechanisms contributing to therapeutic resistance in thyroid cancer and highlight the emerging roles of autophagy and damage associated molecular pattern (DAMP responses in EMT and chemoresistance in tumor cells. Finally, we use the stem cell factor and nucleoprotein High Mobility Group A2 (HMGA2 as an example to demonstrate how factors intended to protect stem cells are wielded by cancer (stem cells to gain increased transformative cell plasticity which enhances metastasis, therapeutic resistance and cell survival. Wherever possible, we have included information on these cellular processes and associated factors as they relate to thyroid cancer cells.

  7. Tumor Cells and Tumor-Associated Macrophages: Secreted Proteins as Potential Targets for Therapy

    OpenAIRE

    Baay, Marc; Brouwer, Anja; Pauwels, Patrick; Peeters, Marc; Lardon, Filip

    2011-01-01

    Inflammatory pathways, meant to defend the organism against infection and injury, as a byproduct, can promote an environment which favors tumor growth and metastasis. Tumor-associated macrophages (TAMs), which constitute a significant part of the tumor-infiltrating immune cells, have been linked to the growth, angiogenesis, and metastasis of a variety of cancers, most likely through polarization of TAMs to the M2 (alternative) phenotype. The interaction between tumor cells and macrophages pro...

  8. Endogenous markers of tumor hypoxia. Predictors of clinical radiation resistance?

    Energy Technology Data Exchange (ETDEWEB)

    Vordermark, D. [Dept. of Radiation Oncology, Univ. of Wuerzburg (Germany); Dept. of Radiation Oncology, Stanford Univ. School of Medicine, Stanford, CA (United States); Brown, J.M. [Dept. of Radiation Oncology, Stanford Univ. School of Medicine, Stanford, CA (United States)

    2003-12-01

    Background: Eppendorf electrode measurements of tumor oxygenation have defined an adverse effect of tumor hypoxia on prognosis after radiotherapy and other treatment modalities, in particular in head and neck and cervix carcinomas as well as soft tissue sarcomas. Recently, the immunohistochemical detection of proteins involved in the ''hypoxic response'' of tumor cells has been discussed as a method to estimate hypoxia in clinical tumor specimens. Material and Methods: This review focuses on clinical and experimental data, regarding prognostic impact and comparability with other methods of hypoxia detection, for three proteins suggested as endogenous markers of tumor hypoxia: hypoxia-inducible factor-1{alpha} (HIF-1{alpha}), carbonic anhydrase 9 (CA 9), and glucose transporter 1 (GLUT1). Results: None of the three potential hypoxia markers is exclusively hypoxia-specific, and in each case protein can be detected under normoxic conditions in vitro. HIF-1{alpha} responds rapidly to hypoxia but also to reoxygenation, making this marker quite unstable in the context of clinical sample collection. The perinecrotic labeling pattern typical of chronic hypoxia and a reasonable agreement with injectable hypoxia markers such as pimonidazole have most consistently been described for CA 9. All three markers showed correlation with Eppendorf electrode measurements of tumor oxygenation in carcinoma of the cervix. In nine of 13 reports, among them all three that refer to curative radiotherapy for head and neck cancer, HIF-1{alpha} overexpression was associated with poor outcome. CA 9 was an adverse prognostic factor in cervix, head and neck and lung cancer, but not in two other head and neck cancer reports. GLUT1 predicted for poor survival in colorectal, cervix and lung cancer. Conclusion: Endogenous markers have the potential to indicate therapeutically relevant levels of hypoxia within tumors. Clinical trials assessing a marker's ability to predict a

  9. Isolation of Circulating Tumor Cells by Dielectrophoresis

    Directory of Open Access Journals (Sweden)

    Peter R. C. Gascoyne

    2014-03-01

    Full Text Available Dielectrophoresis (DEP is an electrokinetic method that allows intrinsic dielectric properties of suspended cells to be exploited for discrimination and separation. It has emerged as a promising method for isolating circulation tumor cells (CTCs from blood. DEP-isolation of CTCs is independent of cell surface markers. Furthermore, isolated CTCs are viable and can be maintained in culture, suggesting that DEP methods should be more generally applicable than antibody-based approaches. The aim of this article is to review and synthesize for both oncologists and biomedical engineers interested in CTC isolation the pertinent characteristics of DEP and CTCs. The aim is to promote an understanding of the factors involved in realizing DEP-based instruments having both sufficient discrimination and throughput to allow routine analysis of CTCs in clinical practice. The article brings together: (a the principles of DEP; (b the biological basis for the dielectric differences between CTCs and blood cells; (c why such differences are expected to be present for all types of tumors; and (d instrumentation requirements to process 10 mL blood specimens in less than 1 h to enable routine clinical analysis. The force equilibrium method of dielectrophoretic field-flow fractionation (DEP-FFF is shown to offer higher discrimination and throughput than earlier DEP trapping methods and to be applicable to clinical studies.

  10. Isolation of Circulating Tumor Cells by Dielectrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Gascoyne, Peter R. C., E-mail: pgascoyn@mdanderson.org [Department of Imaging Physics Research, The University of Texas M.D. Anderson Cancer Center Unit 951, 1515 Holcombe Boulevard, Houston, TX 77030 (United States); Shim, Sangjo [Department of Imaging Physics Research, The University of Texas M.D. Anderson Cancer Center Unit 951, 1515 Holcombe Boulevard, Houston, TX 77030 (United States); Department of Biomedical Engineering, The University of Texas at Austin, 1 University Station, C0800, Austin, TX 78712 (United States); Present address: Micro & Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Urbana, 208 North Wright Street, Urbana, IL 61801 (United States)

    2014-03-12

    Dielectrophoresis (DEP) is an electrokinetic method that allows intrinsic dielectric properties of suspended cells to be exploited for discrimination and separation. It has emerged as a promising method for isolating circulation tumor cells (CTCs) from blood. DEP-isolation of CTCs is independent of cell surface markers. Furthermore, isolated CTCs are viable and can be maintained in culture, suggesting that DEP methods should be more generally applicable than antibody-based approaches. The aim of this article is to review and synthesize for both oncologists and biomedical engineers interested in CTC isolation the pertinent characteristics of DEP and CTCs. The aim is to promote an understanding of the factors involved in realizing DEP-based instruments having both sufficient discrimination and throughput to allow routine analysis of CTCs in clinical practice. The article brings together: (a) the principles of DEP; (b) the biological basis for the dielectric differences between CTCs and blood cells; (c) why such differences are expected to be present for all types of tumors; and (d) instrumentation requirements to process 10 mL blood specimens in less than 1 h to enable routine clinical analysis. The force equilibrium method of dielectrophoretic field-flow fractionation (DEP-FFF) is shown to offer higher discrimination and throughput than earlier DEP trapping methods and to be applicable to clinical studies.

  11. Isolation of Circulating Tumor Cells by Dielectrophoresis

    International Nuclear Information System (INIS)

    Gascoyne, Peter R. C.; Shim, Sangjo

    2014-01-01

    Dielectrophoresis (DEP) is an electrokinetic method that allows intrinsic dielectric properties of suspended cells to be exploited for discrimination and separation. It has emerged as a promising method for isolating circulation tumor cells (CTCs) from blood. DEP-isolation of CTCs is independent of cell surface markers. Furthermore, isolated CTCs are viable and can be maintained in culture, suggesting that DEP methods should be more generally applicable than antibody-based approaches. The aim of this article is to review and synthesize for both oncologists and biomedical engineers interested in CTC isolation the pertinent characteristics of DEP and CTCs. The aim is to promote an understanding of the factors involved in realizing DEP-based instruments having both sufficient discrimination and throughput to allow routine analysis of CTCs in clinical practice. The article brings together: (a) the principles of DEP; (b) the biological basis for the dielectric differences between CTCs and blood cells; (c) why such differences are expected to be present for all types of tumors; and (d) instrumentation requirements to process 10 mL blood specimens in less than 1 h to enable routine clinical analysis. The force equilibrium method of dielectrophoretic field-flow fractionation (DEP-FFF) is shown to offer higher discrimination and throughput than earlier DEP trapping methods and to be applicable to clinical studies

  12. Induction of oncogene addiction shift to NF-κB by camptothecin in solid tumor cells

    International Nuclear Information System (INIS)

    Togano, Tomiteru; Sasaki, Masataka; Watanabe, Mariko; Nakashima, Makoto; Tsuruo, Takashi; Umezawa, Kazuo; Higashihara, Masaaki; Watanabe, Toshiki; Horie, Ryouichi

    2009-01-01

    The biological basis of the resistance of solid tumor cells to chemotherapy is not well understood. While addressing this problem, we found that gastric cancer cell line St-4/CPT, lung cancer cell line A549/CPT, and colon cancer cell line HT-29/CPT, all of which are resistant to camptothecin (CPT), showed strong and constitutive nuclear factor (NF)-κB activity driven by IκB kinase compared with their parental cell lines St-4, A549, and HT-29. A new NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), reduced viability and induced apoptosis in St-4/CPT, A549/CPT, and HT-29/CPT cell lines, while their parental cell lines were resistant to DHMEQ. The results in this study present an example of the shift in signals that support the survival of solid tumor cells to NF-κB during the acquisition of resistance to CPT. The results also indicate that solid tumor cells that become resistant to chemotherapy may be more easily treated by NF-κB inhibitors.

  13. Induction of oncogene addiction shift to NF-{kappa}B by camptothecin in solid tumor cells

    Energy Technology Data Exchange (ETDEWEB)

    Togano, Tomiteru; Sasaki, Masataka; Watanabe, Mariko; Nakashima, Makoto [Department of Hematology, School of Medicine, Kitasato University, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555 (Japan); Tsuruo, Takashi [Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-10-6 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Umezawa, Kazuo [Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-0061 (Japan); Higashihara, Masaaki [Department of Hematology, School of Medicine, Kitasato University, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555 (Japan); Watanabe, Toshiki [Laboratory of Tumor Cell Biology, Department of Medical Genome Sciences, Graduate School of Frontier Sciences, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Horie, Ryouichi, E-mail: rhorie@med.kitasato-u.ac.jp [Department of Hematology, School of Medicine, Kitasato University, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555 (Japan)

    2009-12-04

    The biological basis of the resistance of solid tumor cells to chemotherapy is not well understood. While addressing this problem, we found that gastric cancer cell line St-4/CPT, lung cancer cell line A549/CPT, and colon cancer cell line HT-29/CPT, all of which are resistant to camptothecin (CPT), showed strong and constitutive nuclear factor (NF)-{kappa}B activity driven by I{kappa}B kinase compared with their parental cell lines St-4, A549, and HT-29. A new NF-{kappa}B inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), reduced viability and induced apoptosis in St-4/CPT, A549/CPT, and HT-29/CPT cell lines, while their parental cell lines were resistant to DHMEQ. The results in this study present an example of the shift in signals that support the survival of solid tumor cells to NF-{kappa}B during the acquisition of resistance to CPT. The results also indicate that solid tumor cells that become resistant to chemotherapy may be more easily treated by NF-{kappa}B inhibitors.

  14. Circulating Tumor Cells, Enumeration and Beyond

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Jian-Mei [Clinical and Experimental Pharmacology Group, Paterson Institute for Cancer Research, Manchester M20 4BX (United Kingdom); Krebs, Matthew [Clinical and Experimental Pharmacology Group, Paterson Institute for Cancer Research, Manchester M20 4BX (United Kingdom); Christie Hospital Foundation NHS Trust, Manchester M20 4BX (United Kingdom); Ward, Tim; Morris, Karen; Sloane, Robert [Clinical and Experimental Pharmacology Group, Paterson Institute for Cancer Research, Manchester M20 4BX (United Kingdom); Blackhall, Fiona [Clinical and Experimental Pharmacology Group, Paterson Institute for Cancer Research, Manchester M20 4BX (United Kingdom); School of Cancer and Enabling Sciences, University of Manchester, Manchester Cancer Research Centre, Manchester Academic Health Sciences Centre, Manchester M20 4BX (United Kingdom); Christie Hospital Foundation NHS Trust, Manchester M20 4BX (United Kingdom); Dive, Caroline, E-mail: cdive@picr.man.ac.uk [Clinical and Experimental Pharmacology Group, Paterson Institute for Cancer Research, Manchester M20 4BX (United Kingdom); School of Cancer and Enabling Sciences, University of Manchester, Manchester Cancer Research Centre, Manchester Academic Health Sciences Centre, Manchester M20 4BX (United Kingdom)

    2010-06-09

    The detection and enumeration of circulating tumor cells (CTCs) has shown significant clinical utility with respect to prognosis in breast, colorectal and prostate cancers. Emerging studies show that CTCs can provide pharmacodynamic information to aid therapy decision making. CTCs as a ‘virtual and real-time biopsy’ have clear potential to facilitate exploration of tumor biology, and in particular, the process of metastasis. The challenge of profiling CTC molecular characteristics and generating CTC signatures using current technologies is that they enrich rather than purify CTCs from whole blood; we face the problem of looking for the proverbial ‘needle in the haystack’. This review summarizes the current methods for CTC detection and enumeration, focuses on molecular characterization of CTCs, unveils some aspects of CTC heterogeneity, describes attempts to purify CTCs and scans the horizon for approaches leading to comprehensive dissection of CTC biology.

  15. Circulating tumor cells in breast cancer.

    Science.gov (United States)

    Bidard, Francois-Clement; Proudhon, Charlotte; Pierga, Jean-Yves

    2016-03-01

    Over the past decade, technically reliable circulating tumor cell (CTC) detection methods allowed the collection of large datasets of CTC counts in cancer patients. These data can be used either as a dynamic prognostic biomarker or as tumor material for "liquid biopsy". Breast cancer appears to be the cancer type in which CTC have been the most extensively studied so far, with level-of-evidence-1 studies supporting the clinical validity of CTC count in both early and metastatic stage. This review summarizes and discusses the clinical results obtained in breast cancer patients, the issues faced by the molecular characterization of CTC and the biological findings about cancer biology and metastasis that were obtained from CTC. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  16. Circulating Tumor Cells, Enumeration and Beyond

    International Nuclear Information System (INIS)

    Hou, Jian-Mei; Krebs, Matthew; Ward, Tim; Morris, Karen; Sloane, Robert; Blackhall, Fiona; Dive, Caroline

    2010-01-01

    The detection and enumeration of circulating tumor cells (CTCs) has shown significant clinical utility with respect to prognosis in breast, colorectal and prostate cancers. Emerging studies show that CTCs can provide pharmacodynamic information to aid therapy decision making. CTCs as a ‘virtual and real-time biopsy’ have clear potential to facilitate exploration of tumor biology, and in particular, the process of metastasis. The challenge of profiling CTC molecular characteristics and generating CTC signatures using current technologies is that they enrich rather than purify CTCs from whole blood; we face the problem of looking for the proverbial ‘needle in the haystack’. This review summarizes the current methods for CTC detection and enumeration, focuses on molecular characterization of CTCs, unveils some aspects of CTC heterogeneity, describes attempts to purify CTCs and scans the horizon for approaches leading to comprehensive dissection of CTC biology

  17. Circulating Tumor Cells, Enumeration and Beyond

    Directory of Open Access Journals (Sweden)

    Jian-Mei Hou

    2010-06-01

    Full Text Available The detection and enumeration of circulating tumor cells (CTCs has shown significant clinical utility with respect to prognosis in breast, colorectal and prostate cancers. Emerging studies show that CTCs can provide pharmacodynamic information to aid therapy decision making. CTCs as a ‘virtual and real-time biopsy’ have clear potential to facilitate exploration of tumor biology, and in particular, the process of metastasis. The challenge of profiling CTC molecular characteristics and generating CTC signatures using current technologies is that they enrich rather than purify CTCs from whole blood; we face the problem of looking for the proverbial ‘needle in the haystack’. This review summarizes the current methods for CTC detection and enumeration, focuses on molecular characterization of CTCs, unveils some aspects of CTC heterogeneity, describes attempts to purify CTCs and scans the horizon for approaches leading to comprehensive dissection of CTC biology.

  18. Immunoprotective capability of somatic hybrid cells in comparison with parental tumor cells maintained in vitro

    International Nuclear Information System (INIS)

    Mizushima, Yutaka; Cohen, E.P.

    1985-01-01

    The immunogenicity of X-irradiated hybrid cells derived from fusion of ASL-1 leukemia (A origin) and LM (TK - ) fibroblasts (C3H origin) was compared to X-irradiated parental ASL-1 leukemia cells maintained in vivo (V-ASL-1) and to X-irradiated ASL-1 leukemia cells maintained in vitro (C-ASL-1). Immunization with hybrid cells induced transplantation resistance against tumor rechallenge with V-ASL-1 more effectively than did immunization with V-ASL-1 tumor cells. Immunization with X-irradiated C-ASL-1 cells produced the same, or slightly stronger level of transplantation resistance than that with X-irradiated hybrid cells. These findings were observed both in A/J and in (C3H/HeJxA/J) F 1 mice. These results raise a question about whether the apparent increased immunogenicity of hybrid cells is due to a result of cell fusion or a result of their growth in vitro. (author)

  19. Tumor Cells Express FcγRl Which Contributes to Tumor Cell Growth and a Metastatic Phenotype

    Directory of Open Access Journals (Sweden)

    M. Bud Nelson

    2001-01-01

    Full Text Available High levels of circulating immune complexes containing tumor-associated antigens are associated with a poor prognosis for individuals with cancer. The ability of B cells, previously exposed to tumor-associated antigens, to promote both in vitro and in vivo tumor growth formed the rationale to evaluate the mechanism by which immune complexes may promote tumor growth. In elucidating this mechanism, FcγRl expression by tumor cells was characterized by flow cytometry, polymerase chain reaction, and sequence analysis. Immune complexes containing shed tumor antigen and anti-shed tumor antigen Ab cross-linked FcγRl-expressing tumor cells, which resulted in an induction of tumor cell proliferation and of shed tumor antigen production. Use of selective tyrosine kinase inhibitors demonstrated that tumor cell proliferation induced by immune complex cross-linking of FcγRl is dependent on the tyrosine kinase signal transduction pathway. A selective inhibitor of phosphatidylinositol-3 kinase also inhibited this induction of tumor cell proliferation. These findings support a role for immune complexes and FcγRl expression by tumor cells in augmentation of tumor growth and a metastatic phenotype.

  20. Induction of cancer cell death by proton beam in tumor hypoxic region

    International Nuclear Information System (INIS)

    Hur, T. R.; Lee, Y. M.; Park, J. W.; Sohn, E. J.

    2006-05-01

    The physical properties of charged particles such as protons are uniquely suited to target the radiation dose precisely in the tumor. In proton therapy, the Bragg peak is spread out by modulating or degrading the energy of the particles to cover a well defined target volume at a given depth. Due to heterogeneity in the various tumors and end-points as well as in the physical properties of the beams considered, it is difficult to fit the various results into a clear general description of the biological effect of proton in tumor therapy. Tumor hypoxia is a main obstacle to radiotherapy, including gamma-ray. Survived tumor cells under hypoxic region are resistant to radiation and more aggressive to be metastasized. To investigate the dose of proton beam to induce cell death of various tumor cells and hypoxic tumor cells at the Bragg peak in vitro, we used 3 kinds of tumor cells, lung cancer, leukemia and hepatoma cells. Proton beam induces apoptosis in Lewis lung carcinoma cells dose dependently and, slightly in leukemia but not in hepatoma cells at all. Above 1000 gray of proton beam, 60% of cells died even the hypoxic cells in Lewis lung carcinoma cells. But the Molt-4 leukemia cells showed milder effect, 20% cell death by the above 1000 Gray of proton beam and typical resistant pattern (5-10%) of hypoxia in desferrioxamine treated cells. Hepatoma cells (HepG2) were not responsive to proton beam even in rather higher dose (4000G). However, by the gamma-irradiation, Molt-4 was more sensitive than hepatoma or lung cancer cells, but still showed hypoxic resistance. The cell death by proton beam in Lewis lung carcinoma cells was confirmed by PARP cleavage and may be mediated by increased p53. Pro-caspases were also activated and cleaved by the proton beam irradiations for lung cancer cell death. In conclusion, high dose of proton beam (above 1000 gray) may be a good therapeutic radiation even in hypoxic region at the Bragg peak, but further investigations about the

  1. Tumor-altered dendritic cell function: implications for anti-tumor immunity

    Directory of Open Access Journals (Sweden)

    Kristian Michael Hargadon

    2013-07-01

    Full Text Available Dendritic cells are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programming of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti-tumor

  2. Tumor budding cells, cancer stem cells and epithelial-mesenchymal transition-type cells in pancreatic cancer

    International Nuclear Information System (INIS)

    Karamitopoulou, Eva

    2013-01-01

    Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers with a 5-year survival rate of less than 5%. Moreover, PDAC escapes early detection and resists treatment. Multiple combinations of genetic alterations are known to occur in PDAC including mutational activation of KRAS, inactivation of p16/CDKN2A and SMAD4 (DPC4) and dysregulation of PTEN/PI3K/AKT signaling. Through their interaction with Wingless-INT pathway, the downstream molecules of these pathways have been implicated in the promotion of epithelial–mesenchymal transition (EMT). Emerging evidence has demonstrated that cancer stem cells (CSCs), small populations of which have been identified in PDAC, and EMT-type cells play critical roles in drug resistance, invasion, and metastasis in pancreatic cancer. EMT may be histologically represented by the presence of tumor budding which is described as the occurrence of single tumor cells or small clusters (<5) of dedifferentiated cells at the invasive front of gastrointestinal (including colorectal, oesophageal, gastric, and ampullary) carcinomas and is linked to poor prognosis. Tumor budding has recently been shown to occur frequently in PDAC and to be associated with adverse clinicopathological features and decreased disease-free and overall survival. The aim of this review is to present a short overview on the morphological and molecular aspects that underline the relationship between tumor budding cells, CSCs, and EMT-type cells in PDAC.

  3. Tumor budding cells, cancer stem cells and epithelial-mesenchymal transition-type cells in pancreatic cancer.

    Science.gov (United States)

    Karamitopoulou, Eva

    2012-01-01

    Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers with a 5-year survival rate of less than 5%. Moreover, PDAC escapes early detection and resists treatment. Multiple combinations of genetic alterations are known to occur in PDAC including mutational activation of KRAS, inactivation of p16/CDKN2A and SMAD4 (DPC4) and dysregulation of PTEN/PI3K/AKT signaling. Through their interaction with Wingless-INT pathway, the downstream molecules of these pathways have been implicated in the promotion of epithelial-mesenchymal transition (EMT). Emerging evidence has demonstrated that cancer stem cells (CSCs), small populations of which have been identified in PDAC, and EMT-type cells play critical roles in drug resistance, invasion, and metastasis in pancreatic cancer. EMT may be histologically represented by the presence of tumor budding which is described as the occurrence of single tumor cells or small clusters (<5) of dedifferentiated cells at the invasive front of gastrointestinal (including colorectal, oesophageal, gastric, and ampullary) carcinomas and is linked to poor prognosis. Tumor budding has recently been shown to occur frequently in PDAC and to be associated with adverse clinicopathological features and decreased disease-free and overall survival. The aim of this review is to present a short overview on the morphological and molecular aspects that underline the relationship between tumor budding cells, CSCs, and EMT-type cells in PDAC.

  4. Tumor Budding Cells, Cancer Stem Cells and Epithelial-Mesenchymal Transition-type Cells in Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Eva eKaramitopoulou

    2013-01-01

    Full Text Available Pancreatic ductal adenocarcinoma (PDAC is one of the most lethal cancers with a 5-year survival rate of less than 5%. Moreover, PDAC escapes early detection and resists treatment. Multiple combinations of genetic alterations are known to occur in PDAC including mutational activation of KRAS, inactivation of p16/CDKN2A and SMAD4 (DPC4 and dysregulation of PTEN/PI3K/AKT signaling. Through their interaction with WNT pathway, the downstream molecules of these pathways have been implicated in the promotion of epithelial-mesenchymal transition (EMT. Emerging evidence has demonstrated that cancer stem cells (CSCs, small populations of which have been identified in PDAC, and EMT-type cells play critical roles in drug resistance, invasion and metastasis in pancreatic cancer. EMT may be histologically represented by the presence of tumor budding which is described as the occurrence of single tumor cells or small clusters (<5 of dedifferentiated cells at the invasive front of gastrointestinal (including colorectal, oesophageal, gastric and ampullary carcinomas and is linked to poor prognosis. Tumor budding has recently been shown to occur frequently in PDAC and to be associated with adverse clinicopathological features and decreased disease-free and overall survival. The aim of this review is to present a short overview on the morphological and molecular aspects that underline the relationship between tumor budding cells, CSCs and EMT-type cells in PDAC.

  5. Antigen specific T-cell responses against tumor antigens are controlled by regulatory T cells in patients with prostate cancer.

    Science.gov (United States)

    Hadaschik, Boris; Su, Yun; Huter, Eva; Ge, Yingzi; Hohenfellner, Markus; Beckhove, Philipp

    2012-04-01

    Immunotherapy is a promising approach in an effort to control castration resistant prostate cancer. We characterized tumor antigen reactive T cells in patients with prostate cancer and analyzed the suppression of antitumor responses by regulatory T cells. Peripheral blood samples were collected from 57 patients with histologically confirmed prostate cancer, 8 patients with benign prostatic hyperplasia and 16 healthy donors. Peripheral blood mononuclear cells were isolated and antigen specific interferon-γ secretion of isolated T cells was analyzed by enzyme-linked immunospot assay. T cells were functionally characterized and T-cell responses before and after regulatory T-cell depletion were compared. As test tumor antigens, a panel of 11 long synthetic peptides derived from a total of 8 tumor antigens was used, including prostate specific antigen and prostatic acid phosphatase. In patients with prostate cancer we noted a 74.5% effector T-cell response rate compared with only 25% in patients with benign prostatic hyperplasia and 31% in healthy donors. In most patients 2 or 3 tumor antigens were recognized. Comparing various disease stages there was a clear increase in the immune response against prostate specific antigens from intermediate to high risk tumors and castration resistant disease. Regulatory T-cell depletion led to a significant boost in effector T-cell responses against prostate specific antigen and prostatic acid phosphatase. Tumor specific effector T cells were detected in most patients with prostate cancer, especially those with castration resistant prostate cancer. Since effector T-cell responses against prostate specific antigens strongly increased after regulatory T-cell depletion, our results indicate that immunotherapy efficacy could be enhanced by decreasing regulatory T cells. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  6. Childhood Central Nervous System Germ Cell Tumors Treatment

    Science.gov (United States)

    ... make hormones. Yolk sac tumors make the hormone alpha-fetoprotein (AFP). Mixed germ cell tumors are made of ... used to diagnose some CNS germ cell tumors: Alpha-fetoprotein (AFP). Beta-human chorionic gonadotropin (β-hCG). Blood ...

  7. Radiocolloid Uptake in the Pancreas Islet Cell Tumor: Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Yang, W. J.; Chung, S. K.; Yeon, S. K.; Shinn, K. S.; Bahk, Y. W. [Catholic University College of Medicine, Seoul (Korea, Republic of)

    1994-03-15

    Colloid uptake in various hepatic conditions such as focal nodular hyperplasia, regenerating nodular in the cirrhotic liver, hamartoma, hemangioma and rarely hepatoma has been documented. Extrahepatic tumors may show colloid uptake and they include splenic hemangioma, malignant fibrous histiocytoma, breast carcinoma and Kaposi's sarcoma. The mechanism of colloid uptake in those lesions is associated with phagocytic activity in or around the tumors. We report a pancreas islet cell tumor that showed colloid uptake on {sup 99m}Tc-phytate liver scan without histologic evidence of phagocytosis by tumor cells or infiltration of phagocytes in the tumor. Microscopically the tumor was highly vascular and showed diffuse hemorrhage throughout the tumor. We postulated that extravasation of the colloid into the tumor interstitium caused nonspecific colloid uptake in this tumor. It is expected that hemorrhagic tumor may show nonspecific colloid uptake without phagocytosis in or about the lesion.

  8. Radiocolloid Uptake in the Pancreas Islet Cell Tumor: Case Report

    International Nuclear Information System (INIS)

    Yang, W. J.; Chung, S. K.; Yeon, S. K.; Shinn, K. S.; Bahk, Y. W.

    1994-01-01

    Colloid uptake in various hepatic conditions such as focal nodular hyperplasia, regenerating nodular in the cirrhotic liver, hamartoma, hemangioma and rarely hepatoma has been documented. Extrahepatic tumors may show colloid uptake and they include splenic hemangioma, malignant fibrous histiocytoma, breast carcinoma and Kaposi's sarcoma. The mechanism of colloid uptake in those lesions is associated with phagocytic activity in or around the tumors. We report a pancreas islet cell tumor that showed colloid uptake on 99m Tc-phytate liver scan without histologic evidence of phagocytosis by tumor cells or infiltration of phagocytes in the tumor. Microscopically the tumor was highly vascular and showed diffuse hemorrhage throughout the tumor. We postulated that extravasation of the colloid into the tumor interstitium caused nonspecific colloid uptake in this tumor. It is expected that hemorrhagic tumor may show nonspecific colloid uptake without phagocytosis in or about the lesion.

  9. Modeling the effects of space structure and combination therapies on phenotypic heterogeneity and drug resistance in solid tumors.

    Science.gov (United States)

    Lorz, Alexander; Lorenzi, Tommaso; Clairambault, Jean; Escargueil, Alexandre; Perthame, Benoît

    2015-01-01

    Histopathological evidence supports the idea that the emergence of phenotypic heterogeneity and resistance to cytotoxic drugs can be considered as a process of selection in tumor cell populations. In this framework, can we explain intra-tumor heterogeneity in terms of selection driven by the local cell environment? Can we overcome the emergence of resistance and favor the eradication of cancer cells by using combination therapies? Bearing these questions in mind, we develop a model describing cell dynamics inside a tumor spheroid under the effects of cytotoxic and cytostatic drugs. Cancer cells are assumed to be structured as a population by two real variables standing for space position and the expression level of a phenotype of resistance to cytotoxic drugs. The model takes explicitly into account the dynamics of resources and anticancer drugs as well as their interactions with the cell population under treatment. We analyze the effects of space structure and combination therapies on phenotypic heterogeneity and chemotherapeutic resistance. Furthermore, we study the efficacy of combined therapy protocols based on constant infusion and bang-bang delivery of cytotoxic and cytostatic drugs.

  10. Cancer stem cells in solid tumors: elusive or illusive?

    Directory of Open Access Journals (Sweden)

    Lehrach Hans R

    2010-05-01

    Full Text Available Abstract During the past years in vivo transplantation experiments and in vitro colony-forming assays indicated that tumors arise only from rare cells. These cells were shown to bear self-renewal capacities and the ability to recapitulate all cell types within an individual tumor. Due to their phenotypic resemblance to normal stem cells, the term "cancer stem cells" is used. However, some pieces of the puzzle are missing: (a a stringent definition of cancer stem cells in solid tumors (b specific markers that only target cells that meet the criteria for a cancer stem cell in a certain type of tumor. These missing parts started an ongoing debate about which is the best method to identify and characterize cancer stem cells, or even if their mere existence is just an artifact caused by the experimental procedures. Recent findings query the cancer stem cell hypothesis for solid tumors itself since it was shown in xenograft transplantation experiments that under appropriate conditions tumor-initiating cells are not rare. In this review we critically discuss the challenges and prospects of the currently used major methods to identify cancer stem cells. Further on, we reflect the present discussion about the existence of cancer stem cells in solid tumors as well as the amount and characteristics of tumor-initiating cells and finally provide new perspectives like the correlation of cancer stem cells and induced pluripotent cells.

  11. Anaplasia and drug selection-independent overexpression of the multidrug resistance gene, MDR1, in Wilms' tumor.

    Science.gov (United States)

    Re, G G; Willingham, M C; el Bahtimi, R; Brownlee, N A; Hazen-Martin, D J; Garvin, A J

    1997-02-01

    One reason for the failure of chemotherapy is the overexpression of the multidrug resistance gene, MDR1. The product of this gene is the multidrug transporter P-glycoprotein, an ATP-dependent pump that extrudes drugs from the cytoplasm. Some tumors inherently express P-glycoprotein, whereas others acquire the ability to do so after exposure to certain chemotherapeutic agents, often by the mechanism of gene amplification. Classical Wilms' tumors (nephroblastoma) typically respond to therapy and have a good prognosis. On the contrary, anaplastic Wilms' tumors are generally refractory to chemotherapy. These anaplastic variants are rare (4.5% of all Wilms' tumors reported in the United States), aggressive, and often fatal forms of tumor, which are commonly thought to result from the progression of classical Wilms' tumors. To investigate the basis for this differential response to therapy, we examined a number of classical and anaplastic Wilms' tumors for the expression of the MDR1 gene by immunohistochemical and mRNA analysis. Classical Wilms' tumors consistently did not express P-glycoprotein except in areas of tubular differentiation, as in normal kidney. Similarly, two of three anaplastic tumors failed to show P-glycoprotein expression. In contrast, cultured cells derived from a third anaplastic tumor, W4, exhibited strong P-glycoprotein expression and were drug resistant in vitro. Southern analysis revealed that W4 cells contained a single copy of the MDR1 gene per haploid genome similar to normal cells, demonstrating that the overexpression of MDR1 was not caused by gene amplification. Transcriptional activation of the MDR1 gene would be in keeping with the concept that p53 might act as a transcriptional repressor of the MDR1 gene.

  12. Circulating tumor cells in melanoma patients.

    Directory of Open Access Journals (Sweden)

    Gary A Clawson

    Full Text Available Circulating tumor cells (CTCs are of recognized importance for diagnosis and prognosis of cancer patients. With melanoma, most studies do not show any clear relationship between CTC levels and stage of disease. Here, CTCs were enriched (∼400X from blood of melanoma patients using a simple centrifugation device (OncoQuick, and 4 melanocyte target RNAs (TYR, MLANA, MITF, and MIF were quantified using QPCR. Approximately one-third of melanoma patients had elevated MIF and MLANA transcripts (p<0.0001 and p<0.001, respectively compared with healthy controls. In contrast, healthy controls had uniformly higher levels of TYR and MITF than melanoma patients (p<0.0001. There was a marked shift of leukocytes into the CTC-enriched fractions (a 430% increase in RNA recovery, p<0.001, and no relationship between CTC levels and stage of disease was found. CTCs were captured on microfabricated filters and cultured. Captured melanoma CTCs were large cells, and consisted of 2 subpopulations, based on immunoreactivity. One subpopulation (∼50% stained for both pan-cytokeratin (KRT markers and the common leukocyte marker CD-45, whereas the second subpopulation stained for only KRT. Since similar cells are described in many cancers, we also examined blood from colorectal and pancreatic cancer patients. We observed analogous results, with most captured CTCs staining for both CD-45/KRT markers (and for the monocyte differentiation marker CD-14. Our results suggest that immature melanocyte-related cells (expressing TYR and MITF RNA may circulate in healthy controls, although they are not readily detectable without considerable enrichment. Further, as early-stage melanomas develop, immature melanocyte migration into the blood is somehow curtailed, whereas a significant proportion of patients develop elevated CTC levels (based on MIF and MLANA RNAs. The nature of the captured CTCs is consistent with literature describing leukocyte/macrophage-tumor cell fusion hybrids

  13. Role of multidrug resistance protein (MRP) in glutathione S-conjugate transport in mammalian cells

    NARCIS (Netherlands)

    Müller, M.; de Vries, E. G.; Jansen, P. L.

    1996-01-01

    The human multidrug resistance protein (MRP), a 190-kDa member of the ABC-protein superfamily, is an ATP-dependent glutathione S-conjugate carrier (GS-X pump) and is present in membranes of many, if not all, cells. Overexpression of MRP in tumor cells contributes to resistance to natural product

  14. Role of multidrug resistance protein (MRP) in glutathione S-conjugate transport in mammalian cells

    NARCIS (Netherlands)

    Muller, M; deVries, EGE; Jansen, PLM

    1996-01-01

    The human multidrug resistance protein (MRP), a 190-kDa member of the ABC-protein superfamily, is an ATP-dependent glutathione S-conjugate carrier (GS-X pump) and is present in membranes of many, if not all, cells, Overexpression of MRP in tumor cells contributes to resistance to natural product

  15. Boswellia sacra essential oil induces tumor cell-specific apoptosis and suppresses tumor aggressiveness in cultured human breast cancer cells

    Science.gov (United States)

    2011-01-01

    Background Gum resins obtained from trees of the Burseraceae family (Boswellia sp.) are important ingredients in incense and perfumes. Extracts prepared from Boswellia sp. gum resins have been shown to possess anti-inflammatory and anti-neoplastic effects. Essential oil prepared by distillation of the gum resin traditionally used for aromatic therapy has also been shown to have tumor cell-specific anti-proliferative and pro-apoptotic activities. The objective of this study was to optimize conditions for preparing Boswellea sacra essential oil with the highest biological activity in inducing tumor cell-specific cytotoxicity and suppressing aggressive tumor phenotypes in human breast cancer cells. Methods Boswellia sacra essential oil was prepared from Omani Hougari grade resins through hydrodistillation at 78 or 100 oC for 12 hours. Chemical compositions were identified by gas chromatography-mass spectrometry; and total boswellic acids contents were quantified by high-performance liquid chromatography. Boswellia sacra essential oil-mediated cell viability and death were studied in established human breast cancer cell lines (T47D, MCF7, MDA-MB-231) and an immortalized normal human breast cell line (MCF10-2A). Apoptosis was assayed by genomic DNA fragmentation. Anti-invasive and anti-multicellular tumor properties were evaluated by cellular network and spheroid formation models, respectively. Western blot analysis was performed to study Boswellia sacra essential oil-regulated proteins involved in apoptosis, signaling pathways, and cell cycle regulation. Results More abundant high molecular weight compounds, including boswellic acids, were present in Boswellia sacra essential oil prepared at 100 oC hydrodistillation. All three human breast cancer cell lines were sensitive to essential oil treatment with reduced cell viability and elevated cell death, whereas the immortalized normal human breast cell line was more resistant to essential oil treatment. Boswellia sacra

  16. Tumor initiating cells and chemoresistance: which is the best strategy to target colon cancer stem cells?

    Science.gov (United States)

    Paldino, Emanuela; Tesori, Valentina; Casalbore, Patrizia; Gasbarrini, Antonio; Puglisi, Maria Ausiliatrice

    2014-01-01

    There is an emerging body of evidence that chemoresistance and minimal residual disease result from selective resistance of a cell subpopulation from the original tumor that is molecularly and phenotypically distinct. These cells are called "cancer stem cells" (CSCs). In this review, we analyze the potential targeting strategies for eradicating CSCs specifically in order to develop more effective therapeutic strategies for metastatic colon cancer. These include induction of terminal epithelial differentiation of CSCs or targeting some genes expressed only in CSCs and involved in self-renewal and chemoresistance. Ideal targets could be cell regulators that simultaneously control the stemness and the resistance of CSCs. Another important aspect of cancer biology, which can also be harnessed to create novel broad-spectrum anticancer agents, is the Warburg effect, also known as aerobic glycolysis. Actually, little is yet known with regard to the metabolism of CSCs population, leaving an exciting unstudied avenue in the dawn of the emerging field of metabolomics.

  17. Fibrocytes: A Novel Stromal Cells to Regulate Resistance to Anti-Angiogenic Therapy and Cancer Progression.

    Science.gov (United States)

    Goto, Hisatsugu; Nishioka, Yasuhiko

    2017-12-29

    An adequate blood supply is essential for cancer cells to survive and grow; thus, the concept of inhibiting tumor angiogenesis has been applied to cancer therapy, and several drugs are already in clinical use. It has been shown that treatment with those anti-angiogenic drugs improved the response rate and prolonged the survival of patients with various types of cancer; however, it is also true that the effect was mostly limited. Currently, the disappointing clinical results are explained by the existence of intrinsic or acquired resistance to the therapy mediated by both tumor cells and stromal cells. This article reviews the mechanisms of resistance mediated by stromal cells such as endothelial cells, pericytes, fibroblasts and myeloid cells, with an emphasis on fibrocytes, which were recently identified as the cell type responsible for regulating acquired resistance to anti-angiogenic therapy. In addition, the other emerging role of fibrocytes as mediator-producing cells in tumor progression is discussed.

  18. Granular cell tumor of the esophagus. Report of three cases.

    Science.gov (United States)

    Cohle, S D; McKechnie, J C; Truong, L; Jurco, S

    1981-06-01

    Granular cell tumors, (formerly called myoblastomas) involving the esophagus were encountered in three patients. In all three the tumors were asymptomatic and in two they were multiple. The first published endoscopic photographs of such a tumor are presented. The successful total removal of this neoplasm using the endoscope is described. The pathologic, radiologic and therapeutic aspects of previously reported cases of granular cell tumor of the esophagus are reviewed and compared with the three reported herein.

  19. Adipose Expression of Tumor Necrosis Factor-α: Direct Role in Obesity-Linked Insulin Resistance

    Science.gov (United States)

    Hotamisligil, Gokhan S.; Shargill, Narinder S.; Spiegelman, Bruce M.

    1993-01-01

    Tumor necrosis factor-α (TNF-α) has been shown to have certain catabolic effects on fat cells and whole animals. An induction of TNF-α messenger RNA expression was observed in adipose tissue from four different rodent models of obesity and diabetes. TNF-α protein was also elevated locally and systemically. Neutralization of TNF-α in obese fa/fa rats caused a significant increase in the peripheral uptake of glucose in response to insulin. These results indicate a role for TNF-α in obesity and particularly in the insulin resistance and diabetes that often accompany obesity.

  20. Dragon (RGMb) induces oxaliplatin resistance in colon cancer cells.

    Science.gov (United States)

    Shi, Ying; Huang, Xiao-Xiao; Chen, Guo-Bin; Wang, Ying; Zhi, Qiang; Liu, Yuan-Sheng; Wu, Xiao-Ling; Wang, Li-Fen; Yang, Bing; Xiao, Chuan-Xing; Xing, Hui-Qin; Ren, Jian-Lin; Xia, Yin; Guleng, Bayasi

    2016-07-26

    Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and a major cause of cancer mortality. Chemotherapy resistance remains a major challenge for treating advanced CRC. Therefore, the identification of targets that induce drug resistance is a priority for the development of novel agents to overcome resistance. Dragon (also known as RGMb) is a member of the repulsive guidance molecule (RGM) family. We previously showed that Dragon expression increases with CRC progression in human patients. In the present study, we found that Dragon inhibited apoptosis and increased viability of CMT93 and HCT116 cells in the presence of oxaliplatin. Dragon induced resistance of xenograft tumor to oxaliplatinin treatment in mice. Mechanistically, Dragon inhibited oxaliplatin-induced JNK and p38 MAPK activation, and caspase-3 and PARP cleavages. Our results indicate that Dragon may be a novel target that induces drug resistance in CRC.

  1. Non-cell autonomous or secretory tumor suppression.

    Science.gov (United States)

    Chua, Christelle En Lin; Chan, Shu Ning; Tang, Bor Luen

    2014-10-01

    Many malignancies result from deletions or loss-of-function mutations in one or more tumor suppressor genes, the products of which curb unrestrained growth or induce cell death in those with dysregulated proliferative capacities. Most tumor suppressors act in a cell autonomous manner, and only very few proteins are shown to exert a non-cell autonomous tumor suppressor function on other cells. Examples of these include members of the secreted frizzled-related protein (SFRP) family and the secreted protein acidic and rich in cysteine (SPARC)-related proteins. Very recent findings have, however, considerably expanded our appreciation of non-cell autonomous tumor suppressor functions. Broadly, this may occur in two ways. Intracellular tumor suppressor proteins within cells could in principle inhibit aberrant growth of neighboring cells by conditioning an antitumor microenvironment through secreted factors. This is demonstrated by an apparent non-cell autonomous tumor suppressing property of p53. On the other hand, a tumor suppressor produced by a cell may be secreted extracellularly, and taken up by another cell with its activity intact. Intriguingly, this has been recently shown to occur for the phosphatase and tensin homolog (PTEN) by both conventional and unconventional modes of secretion. These recent findings would aid the development of therapeutic strategies that seek to reinstate tumor suppression activity in therapeutically recalcitrant tumor cells, which have lost it in the first place. © 2014 Wiley Periodicals, Inc.

  2. Bortezomib resistance in mantle cell lymphoma is associated with plasmacytic differentiation

    DEFF Research Database (Denmark)

    Pérez-Galán, Patricia; Mora-Jensen, Helena; Weniger, Marc A

    2011-01-01

    bortezomib-resistant MCL cell lines and primary tumor cells from MCL patients with inferior clinical response to bortezomib also expressed plasmacytic features. Knockdown of IRF4 was toxic for the subset of MCL cells with plasmacytic differentiation, but only slightly sensitized cells to bortezomib. We...

  3. Circulating cell-free DNA and circulating tumor cells, the "liquid biopsies" in ovarian cancer.

    Science.gov (United States)

    Cheng, Xianliang; Zhang, Lei; Chen, Yajuan; Qing, Chen

    2017-11-13

    Limited understanding of ovarian cancer (OC) genome portrait has hindered the therapeutic advances. The serial monitoring of tumor genotypes is becoming increasingly attainable with circulating cell-free DNA (cf-DNA) and circulating tumor cells (CTCs) emerging as "liquid biopsies". They represent non-invasive biomarkers and are viable, as they can be isolated from human plasma, serum and other body fluids. Molecular characterization of circulating tumor DNA (ct-DNA) and CTCs offer unique potentials to better understand the biology of metastasis and resistance to therapies. The liquid biopsies may also give innovative insights into the process of rapid and accurate identification, resistant genetic alterations and a real time monitoring of treatment responses. In addition, liquid biopsies are shedding light on elucidating signal pathways involved in invasiveness and metastasis competence; but the detection and molecular characterization of ct-DNA and CTCs are still challenging, since they are rare, and the amount of available samples are very limited. This review will focus on the clinical potential of ct-DNA and CTCs in both the early and advanced diagnosis, prognosis, and in the identification of resistance mutations in OC.

  4. Novel nanostructured enoxaparin sodium-PLGA hybrid carriers overcome tumor multidrug resistance of doxorubicin hydrochloride.

    Science.gov (United States)

    Wang, Jia; Wu, Lei; Kou, Longfa; Xu, Meng; Sun, Jin; Wang, Yongjun; Fu, Qiang; Zhang, Peng; He, Zhonggui

    2016-11-20

    Novel enoxaparin sodium-PLGA hybrid nanocarries (EPNs) were successfully designed for sustained delivery of hydrophilic cationic doxorubicin hydrochloride (DOX) and to overcome multidrug resistance (MDR). By incorporation of the negative polymer of enoxaparin sodium (ES), DOX was highly encapsulated into EPNs with an encapsulation efficiency of 92.49%, and ES effectively inhibited the proliferation of HUVEC cell lines. The in vivo pharmacokinetics study after intravenous injection indicated that DOX-loaded EPNs (DOX-EPNs) exhibited a higher area under the curve (AUC) and a longer half-life (t 1/2 ) in comparison with DOX solution (DOX-Sol). The biodistribution study demonstrated that DOX-EPNs increased the DOX level in plasma and decreased the accumulation of DOX in liver and spleen. Compared with DOX-Sol, DOX-EPNs increased the cytotoxicity in P-gp over-expressing MCF-7/Adr cells, attributed to the higher intracellular efficiency of DOX produced by the EPNs. DOX-EPNs entered into resistant tumor cells by multiple endocytosis pathways, which resulted in overcoming the multidrug resistance of MCF-7/Adr cells by escaping the efflux induced by P-gp transporters. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Inhibition of NF-κB in Tumor Cells Exacerbates Immune Cell Activation Following Photodynamic Therapy

    Science.gov (United States)

    Broekgaarden, Mans; Kos, Milan; Jurg, Freek A.; van Beek, Adriaan A.; van Gulik, Thomas M.; Heger, Michal

    2015-01-01

    Although photodynamic therapy (PDT) yields very good outcomes in numerous types of superficial solid cancers, some tumors respond suboptimally to PDT. Novel treatment strategies are therefore needed to enhance the efficacy in these therapy-resistant tumors. One of these strategies is to combine PDT with inhibitors of PDT-induced survival pathways. In this respect, the transcription factor nuclear factor κB (NF-κB) has been identified as a potential pharmacological target, albeit inhibition of NF-κB may concurrently dampen the subsequent anti-tumor immune response required for complete tumor eradication and abscopal effects. In contrast to these postulations, this study demonstrated that siRNA knockdown of NF-κB in murine breast carcinoma (EMT-6) cells increased survival signaling in these cells and exacerbated the inflammatory response in murine RAW 264.7 macrophages. These results suggest a pro-death and immunosuppressive role of NF-κB in PDT-treated cells that concurs with a hyperstimulated immune response in innate immune cells. PMID:26307977

  6. Tumor Architecture and Notch Signaling Modulate Drug Response in Basal Cell Carcinoma.

    Science.gov (United States)

    Eberl, Markus; Mangelberger, Doris; Swanson, Jacob B; Verhaegen, Monique E; Harms, Paul W; Frohm, Marcus L; Dlugosz, Andrzej A; Wong, Sunny Y

    2018-02-12

    Hedgehog (Hh) pathway inhibitors such as vismodegib are highly effective for treating basal cell carcinoma (BCC); however, residual tumor cells frequently persist and regenerate the primary tumor upon drug discontinuation. Here, we show that BCCs are organized into two molecularly and functionally distinct compartments. Whereas interior Hh + /Notch + suprabasal cells undergo apoptosis in response to vismodegib, peripheral Hh +++ /Notch - basal cells survive throughout treatment. Inhibiting Notch specifically promotes tumor persistence without causing drug resistance, while activating Notch is sufficient to regress already established lesions. Altogether, these findings suggest that the three-dimensional architecture of BCCs establishes a natural hierarchy of drug response in the tumor and that this hierarchy can be overcome, for better or worse, by modulating Notch. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. EGFR overexpressing cells and tumors are dependent on autophagy for growth and survival

    International Nuclear Information System (INIS)

    Jutten, Barry; Keulers, Tom G.; Schaaf, Marco B.E.; Savelkouls, Kim; Theys, Jan; Span, Paul N.; Vooijs, Marc A.; Bussink, Johan; Rouschop, Kasper M.A.

    2013-01-01

    Background and purpose: The epidermal growth factor receptor (EGFR) is overexpressed, amplified or mutated in various human epithelial tumors, and is associated with tumor aggressiveness and therapy resistance. Autophagy activation provides a survival advantage for cells in the tumor microenvironment. In the current study, we assessed the potential of autophagy inhibition (using chloroquine (CQ)) in treatment of EGFR expressing tumors. Material and methods: Quantitative PCR, immunohistochemistry, clonogenic survival, proliferation assays and in vivo tumor growth were used to assess this potential. Results: We show that EGFR overexpressing xenografts are sensitive to CQ treatment and are sensitized to irradiation by autophagy inhibition. In HNSSC xenografts, a correlation between EGFR and expression of the autophagy marker LC3b is observed, suggesting a role for autophagy in EGFR expressing tumors. This observation was substantiated in cell lines, showing high EGFR expressing cells to be more sensitive to CQ addition as reflected by decreased proliferation and survival. Surprisingly high EGFR expressing cells display a lower autophagic flux. Conclusions: The EGFR high expressing cells and tumors investigated in this study are highly dependent on autophagy for growth and survival. Inhibition of autophagy may therefore provide a novel treatment opportunity for EGFR overexpressing tumors

  8. Ovarian granulosa cell tumors : histopathology, immunopathology and prognosis

    NARCIS (Netherlands)

    S. Chadha-Ajwani (Savi)

    1987-01-01

    textabstractGranulosa cell tumors (GCT) of the ovary account for 2% of all ovarian tumors. As the name indicates, they are composed of granulosa cells but may also contain an admixture of theca cells. They are potentially malignant but, except for extraovarian spread, which is generally agreed

  9. Vitamin C deficiency aggravates tumor necrosis factor α-induced insulin resistance.

    Science.gov (United States)

    Qing, Zhou; Xiao-Hui, Wu; Xi-Mei, Wu; Chao-Chun, Zou

    2018-06-15

    Chronic low-grade inflammation plays a major role in the development of insulin resistance. The potential role and underlying mechanism of vitamin C, an antioxidant and anti-inflammatory agent, was investigated in tumor necrosis factor-α (TNF-α)-induced insulin resistance. Gulonolactone oxidase knockout (Gulo -/- ) mice genetically unable to synthesize vitamin C were used to induce insulin resistance by continuously pumping small doses of TNF-α for seven days, and human liver hepatocellular carcinoma cells (HepG2 cells) were used to induce insulin resistance by treatment with TNF-α. Vitamin C deficiency aggravated TNF-α-induced insulin resistance in Gulo -/- mice, resulting in worse glucose tolerance test (GTT) results, higher fasting plasma insulin level, and the inactivation of the protein kinase B (AKT)/glycogen synthase kinase-3β (GSK3β) pathway in the liver. Vitamin C deficiency also worsened liver lipid accumulation and inflammation in TNF-α-treated Gulo -/- mice. In HepG2 cells, vitamin C reversed the TNF-α-induced reduction of glucose uptake and glycogen synthesis, which were mediated by increasing GLUT2 levels and the activation of the insulin receptor substrate (IRS-1)/AKT/GSK3β pathway. Furthermore, vitamin C inhibited the TNF-α-induced activation of not only the mitogen-activated protein kinase (MAPKs), but also nuclear factor-kappa B (NF-κB) signaling. Taken together, vitamin C is essential for preventing and improving insulin resistance, and the supplementing with vitamin C may be an effective therapeutic intervention for metabolic disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Effects of alkylating carcinogens on human tumor cells in culture

    International Nuclear Information System (INIS)

    Goth-Goldstein, R.; Hughes, M.

    1987-01-01

    In Escherichia coli 3-methyladenine and 3-methylguanine have been identified as lethal lesions, since two types of alkylating agent-sensitive mutants were deficient in repair of either of these lesions. Similar alkylation-sensitive human cell lines exist. These are the tumor cell lines of the complex Mer - phenotype. All Mer - cells examined were hypersensitive to killing by MNNG and other alkylating agents, and failed to repair O 6 -methylguanine. The widely studied HeLa S3 cell line has the Mer + phenotype, but a Mer - variant (HeLa MR) has arisen. This offers the possibility to study Mer - and Mer + cells of otherwise similar genetic background. We are using these two variants to analyze the Mer - phenotype further. When HeLa S3 and HeLa MR were treated with a highly dose of MNNG, and the surviving population exposed to a second dose of MNNG 2-3 weeks later, HeLa S3 (Mer + ) cells were equally or even slightly more sensitive to a second exposure of MNNG, whereas the surviving HeLa MR (Mer - ) population was much more resistant to MNNG. 1 fig., 1 tab

  11. Antitumor action of 3-bromopyruvate implicates reorganized tumor growth regulatory components of tumor milieu, cell cycle arrest and induction of mitochondria-dependent tumor cell death.

    Science.gov (United States)

    Yadav, Saveg; Kujur, Praveen Kumar; Pandey, Shrish Kumar; Goel, Yugal; Maurya, Babu Nandan; Verma, Ashish; Kumar, Ajay; Singh, Rana Pratap; Singh, Sukh Mahendra

    2018-01-15

    Evidences demonstrate that metabolic inhibitor 3-bromopyruvate (3-BP) exerts a potent antitumor action against a wide range of malignancies. However, the effect of 3-BP on progression of the tumors of thymic origin remains unexplored. Although, constituents of tumor microenvironment (TME) plays a pivotal role in regulation of tumor progression, it remains unclear if 3-BP can alter the composition of the crucial tumor growth regulatory components of the external surrounding of tumor cells. Thus, the present investigation attempts to understand the effect of 3-BP administration to a host bearing a progressively growing tumor of thymic origin on tumor growth regulatory soluble, cellular and biophysical components of tumor milieu vis-à-vis understanding its association with tumor progression, accompanying cell cycle events and mode of cell death. Further, the expression of cell survival regulatory molecules and hemodynamic characteristics of the tumor milieu were analysed to decipher mechanisms underlying the antitumor action of 3-BP. Administration of 3-BP to tumor-bearing hosts retarded tumor progression accompanied by induction of tumor cell death, cell cycle arrest, declined metabolism, inhibited mitochondrial membrane potential, elevated release of cytochrome c and altered hemodynamics. Moreover, 3-BP reconstituted the external milieu, in concurrence with deregulated glucose and pH homeostasis and increased tumor infiltration by NK cells, macrophages, and T lymphocytes. Further, 3-BP administration altered the expression of key regulatory molecules involved in glucose uptake, intracellular pH and tumor cell survival. The outcomes of this study will help in optimizing the therapeutic application of 3-BP by targeting crucial tumor growth regulatory components of tumor milieu. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Solid KHT tumor dispersal for flow cytometric cell kinetic analysis

    International Nuclear Information System (INIS)

    Pallavicini, M.G.; Folstad, L.J.; Dunbar, C.

    1981-01-01

    A bacterial neutral protease was used to disperse KHT solid tumors into single cell suspensions suitable for routine cell kinetic analysis by flow cytometry and for clonogenic cell survival. Neutral protease disaggregation under conditions which would be suitable for routine tumor dispersal was compared with a trypsin/DNase procedure. Cell yield, clonogenic cell survival, DNA distributions of untreated and drug-perturbed tumors, rates of radioactive precursor incorporation during the cell cycle, and preferential cell cycle phase-specific cell loss were investigated. Tumors dispersed with neutral protease yielded approximately four times more cells than those dispersed with trypsin/DNase and approximately a 1.5-fold higher plating efficiency in a semisolid agar system. Quantitative analysis of DNA distributions obtained from untreated and cytosine-arabinoside-perturbed tumors produced similar results with both dispersal procedures. The rates of incorporation of tritiated thymidine during the cell cycle were also similar with neutral protease and trypsin/DNase dispersal. Preferential phase-specific cell loss was not obseved with either technique. We find that neutral protease provides good single cell suspensions of the KHT tumor for cell survival measurements and for cell kinetic analysis of drug-induced perturbations by flow cytometry. In addition, the high cell yields facilitate electronic cell sorting where large numbers of cells are often required

  13. Loss of TRPV2 Homeostatic Control of Cell Proliferation Drives Tumor Progression

    Directory of Open Access Journals (Sweden)

    Sonia Liberati

    2014-02-01

    Full Text Available Herein we evaluate the involvement of the TRPV2 channel, belonging to the Transient Receptor Potential Vanilloid channel family (TRPVs, in development and progression of different tumor types. In normal cells, the activation of TRPV2 channels by growth factors, hormones, and endocannabinoids induces a translocation of the receptor from the endosomal compartment to the plasma membrane, which results in abrogation of cell proliferation and induction of cell death. Consequently, loss or inactivation of TRPV2 signaling (e.g., glioblastomas, induces unchecked proliferation, resistance to apoptotic signals and increased resistance to CD95-induced apoptotic cell death. On the other hand, in prostate cancer cells, Ca2+-dependent activation of TRPV2 induced by lysophospholipids increases the invasion of tumor cells. In addition, the progression of prostate cancer to the castration-resistant phenotype is characterized by de novo TRPV2 expression, with higher TRPV2 transcript levels in patients with metastatic cancer. Finally, TRPV2 functional expression in tumor cells can also depend on the presence of alternative splice variants of TRPV2 mRNA that act as dominant-negative mutant of wild-type TRPV2 channels, by inhibiting its trafficking and translocation to the plasma membrane. In conclusion, as TRP channels are altered in human cancers, and their blockage impair tumor progression, they appear to be a very promising targets for early diagnosis and chemotherapy.

  14. Clinical relevance and biology of circulating tumor cells

    Science.gov (United States)

    2011-01-01

    Most breast cancer patients die due to metastases, and the early onset of this multistep process is usually missed by current tumor staging modalities. Therefore, ultrasensitive techniques have been developed to enable the enrichment, detection, isolation and characterization of disseminated tumor cells in bone marrow and circulating tumor cells in the peripheral blood of cancer patients. There is increasing evidence that the presence of these cells is associated with an unfavorable prognosis related to metastatic progression in the bone and other organs. This review focuses on investigations regarding the biology and clinical relevance of circulating tumor cells in breast cancer. PMID:22114869

  15. In Silico Analysis of Microarray-Based Gene Expression Profiles Predicts Tumor Cell Response to Withanolides

    Directory of Open Access Journals (Sweden)

    Thomas Efferth

    2012-05-01

    Full Text Available Withania somnifera (L. Dunal (Indian ginseng, winter cherry, Solanaceae is widely used in traditional medicine. Roots are either chewed or used to prepare beverages (aqueous decocts. The major secondary metabolites of Withania somnifera are the withanolides, which are C-28-steroidal lactone triterpenoids. Withania somnifera extracts exert chemopreventive and anticancer activities in vitro and in vivo. The aims of the present in silico study were, firstly, to investigate whether tumor cells develop cross-resistance between standard anticancer drugs and withanolides and, secondly, to elucidate the molecular determinants of sensitivity and resistance of tumor cells towards withanolides. Using IC50 concentrations of eight different withanolides (withaferin A, withaferin A diacetate, 3-azerininylwithaferin A, withafastuosin D diacetate, 4-B-hydroxy-withanolide E, isowithanololide E, withafastuosin E, and withaperuvin and 19 established anticancer drugs, we analyzed the cross-resistance profile of 60 tumor cell lines. The cell lines revealed cross-resistance between the eight withanolides. Consistent cross-resistance between withanolides and nitrosoureas (carmustin, lomustin, and semimustin was also observed. Then, we performed transcriptomic microarray-based COMPARE and hierarchical cluster analyses of mRNA expression to identify mRNA expression profiles predicting sensitivity or resistance towards withanolides. Genes from diverse functional groups were significantly associated with response of tumor cells to withaferin A diacetate, e.g. genes functioning in DNA damage and repair, stress response, cell growth regulation, extracellular matrix components, cell adhesion and cell migration, constituents of the ribosome, cytoskeletal organization and regulation, signal transduction, transcription factors, and others.

  16. Tumor-derived circulating endothelial cell clusters in colorectal cancer.

    KAUST Repository

    Cima, Igor; Kong, Say Li; Sengupta, Debarka; Tan, Iain B; Phyo, Wai Min; Lee, Daniel; Hu, Min; Iliescu, Ciprian; Alexander, Irina; Goh, Wei Lin; Rahmani, Mehran; Suhaimi, Nur-Afidah Mohamed; Vo, Jess H; Tai, Joyce A; Tan, Joanna H; Chua, Clarinda; Ten, Rachel; Lim, Wan Jun; Chew, Min Hoe; Hauser, Charlotte; van Dam, Rob M; Lim, Wei-Yen; Prabhakar, Shyam; Lim, Bing; Koh, Poh Koon; Robson, Paul; Ying, Jackie Y; Hillmer, Axel M; Tan, Min-Han

    2016-01-01

    Clusters of tumor cells are often observed in the blood of cancer patients. These structures have been described as malignant entities for more than 50 years, although their comprehensive characterization is lacking. Contrary to current consensus, we demonstrate that a discrete population of circulating cell clusters isolated from the blood of colorectal cancer patients are not cancerous but consist of tumor-derived endothelial cells. These clusters express both epithelial and mesenchymal markers, consistent with previous reports on circulating tumor cell (CTC) phenotyping. However, unlike CTCs, they do not mirror the genetic variations of matched tumors. Transcriptomic analysis of single clusters revealed that these structures exhibit an endothelial phenotype and can be traced back to the tumor endothelium. Further results show that tumor-derived endothelial clusters do not form by coagulation or by outgrowth of single circulating endothelial cells, supporting a direct release of clusters from the tumor vasculature. The isolation and enumeration of these benign clusters distinguished healthy volunteers from treatment-naïve as well as pathological early-stage (≤IIA) colorectal cancer patients with high accuracy, suggesting that tumor-derived circulating endothelial cell clusters could be used as a means of noninvasive screening for colorectal cancer. In contrast to CTCs, tumor-derived endothelial cell clusters may also provide important information about the underlying tumor vasculature at the time of diagnosis, during treatment, and throughout the course of the disease.

  17. Tumor-derived circulating endothelial cell clusters in colorectal cancer.

    KAUST Repository

    Cima, Igor

    2016-06-29

    Clusters of tumor cells are often observed in the blood of cancer patients. These structures have been described as malignant entities for more than 50 years, although their comprehensive characterization is lacking. Contrary to current consensus, we demonstrate that a discrete population of circulating cell clusters isolated from the blood of colorectal cancer patients are not cancerous but consist of tumor-derived endothelial cells. These clusters express both epithelial and mesenchymal markers, consistent with previous reports on circulating tumor cell (CTC) phenotyping. However, unlike CTCs, they do not mirror the genetic variations of matched tumors. Transcriptomic analysis of single clusters revealed that these structures exhibit an endothelial phenotype and can be traced back to the tumor endothelium. Further results show that tumor-derived endothelial clusters do not form by coagulation or by outgrowth of single circulating endothelial cells, supporting a direct release of clusters from the tumor vasculature. The isolation and enumeration of these benign clusters distinguished healthy volunteers from treatment-naïve as well as pathological early-stage (≤IIA) colorectal cancer patients with high accuracy, suggesting that tumor-derived circulating endothelial cell clusters could be used as a means of noninvasive screening for colorectal cancer. In contrast to CTCs, tumor-derived endothelial cell clusters may also provide important information about the underlying tumor vasculature at the time of diagnosis, during treatment, and throughout the course of the disease.

  18. The use of bispecific antibodies in tumor cell and tumor vasculature directed immunotherapy

    NARCIS (Netherlands)

    Molema, G; Kroesen, BJ; Helfrich, W; Meijer, DKF; de Leij, LFMH

    2000-01-01

    To overcome dose limiting toxicities and to increase efficacy of immunotherapy of cancer, a number of strategies are under development for selectively redirecting effector cells/molecules towards tumor cells. Many of these strategies exploit the specificity of tumor associated antigen recognition by

  19. Vaccination with Necroptotic Cancer Cells Induces Efficient Anti-tumor Immunity

    Directory of Open Access Journals (Sweden)

    Tania Løve Aaes

    2016-04-01

    Full Text Available Successful immunogenic apoptosis in experimental cancer therapy depends on the induction of strong host anti-tumor responses. Given that tumors are often resistant to apoptosis, it is important to identify alternative molecular mechanisms that elicit immunogenic cell death. We have developed a genetic model in which direct dimerization of FADD combined with inducible expression of RIPK3 promotes necroptosis. We report that necroptotic cancer cells release damage-associated molecular patterns and promote maturation of dendritic cells, the cross-priming of cytotoxic T cells, and the production of IFN-γ in response to tumor antigen stimulation. Using both FADD-dependent and FADD-independent RIPK3 induction systems, we demonstrate the efficient vaccination potential of immunogenic necroptotic cells. Our study broadens the current concept of immunogenic cell death and opens doors for the development of new strategies in cancer therapy.

  20. Treatment Options for Childhood Extracranial Germ Cell Tumors

    Science.gov (United States)

    ... tumors: Yolk sac tumors make a hormone called alpha-fetoprotein (AFP). They can form in the ovary, testicle, ... are used to detect extracranial germ cell tumors: Alpha-fetoprotein (AFP). Beta-human chorionic gonadotropin (β-hCG). For ...

  1. General Information about Childhood Extracranial Germ Cell Tumors

    Science.gov (United States)

    ... tumors: Yolk sac tumors make a hormone called alpha-fetoprotein (AFP). They can form in the ovary, testicle, ... are used to detect extracranial germ cell tumors: Alpha-fetoprotein (AFP). Beta-human chorionic gonadotropin (β-hCG). For ...

  2. Flow cytometric DNA ploidy analysis of ovarian granulosa cell tumors

    NARCIS (Netherlands)

    D. Chadha; C.J. Cornelisse; A. Schabert (A.)

    1990-01-01

    textabstractAbstract The nuclear DNA content of 50 ovarian tumors initially diagnosed as granulosa cell tumors was measured by flow cytometry using paraffin-embedded archival material. The follow-up period of the patients ranged from 4 months to 19 years. Thirty-eight tumors were diploid or

  3. Engineering a prostate-specific membrane antigen-activated tumor endothelial cell prodrug for cancer therapy.

    Science.gov (United States)

    Denmeade, Samuel R; Mhaka, Annastasiah M; Rosen, D Marc; Brennen, W Nathaniel; Dalrymple, Susan; Dach, Ingrid; Olesen, Claus; Gurel, Bora; Demarzo, Angelo M; Wilding, George; Carducci, Michael A; Dionne, Craig A; Møller, Jesper V; Nissen, Poul; Christensen, S Brøgger; Isaacs, John T

    2012-06-27

    Heterogeneous expression of drug target proteins within tumor sites is a major mechanism of resistance to anticancer therapies. We describe a strategy to selectively inhibit, within tumor sites, the function of a critical intracellular protein, the sarcoplasmic/endoplasmic reticulum calcium adenosine triphosphatase (SERCA) pump, whose proper function is required by all cell types for viability. To achieve targeted inhibition, we took advantage of the unique expression of the carboxypeptidase prostate-specific membrane antigen (PSMA) by tumor endothelial cells within the microenvironment of solid tumors. We generated a prodrug, G202, consisting of a PSMA-specific peptide coupled to an analog of the potent SERCA pump inhibitor thapsigargin. G202 produced substantial tumor regression against a panel of human cancer xenografts in vivo at doses that were minimally toxic to the host. On the basis of these data, a phase 1 dose-escalation clinical trial has been initiated with G202 in patients with advanced cancer.

  4. Diffuse Reflectance Spectroscopy (DRS) of radiation-induced re-oxygenation in sensitive and resistant head and neck tumor xenografts

    Science.gov (United States)

    Dadgar, Sina; Rodríguez Troncoso, Joel; Rajaram, Narasimhan

    2018-02-01

    Currently, anatomical assessment of tumor volume performed several weeks after completion of treatment is the clinical standard to determine whether a cancer patient has responded to a treatment. However, functional changes within the tumor could potentially provide information regarding treatment resistance or response much earlier than anatomical changes. We have used diffuse reflectance spectroscopy to assess the short and long-term re-oxygenation kinetics of a human head and neck squamous cell carcinoma xenografts in response to radiation therapy. First, we injected UM-SCC-22B cell line into the flank of 50 mice to grow xenografts. Once the tumor volume reached 200 mm3 (designated as Day 1), the mice were distributed into radiation and control groups. Members of radiation group underwent a clinical dose of radiation of 2 Gy/day on Days 1, 4, 7, and 10 for a cumulative dose of 8 Gy. DRS spectra of these tumors were collected for 14 days during and after therapy, and the collected spectra of each tumor were converted to its optical properties using a lookup table-base inverse model. We found statistically significant differences in tumor growth rate between two groups which is in indication of the sensitivity of this cell line to radiation. We further acquired significantly different contents of hemoglobin and scattering magnitude and size in two groups. The scattering has previously been associated with necrosis. We furthermore found significantly different time-dependent changes in vascular oxygenation and tumor hemoglobin concentration in post-radiation days.

  5. Resistance exercise attenuates skeletal muscle oxidative stress, systemic pro-inflammatory state, and cachexia in Walker-256 tumor-bearing rats.

    Science.gov (United States)

    Padilha, Camila Souza; Borges, Fernando Henrique; Costa Mendes da Silva, Lilian Eslaine; Frajacomo, Fernando Tadeu Trevisan; Jordao, Alceu Afonso; Duarte, José Alberto; Cecchini, Rubens; Guarnier, Flávia Alessandra; Deminice, Rafael

    2017-09-01

    The aim of this study was to investigate the effects of resistance exercise training (RET) on oxidative stress, systemic inflammatory markers, and muscle wasting in Walker-256 tumor-bearing rats. Male (Wistar) rats were divided into 4 groups: sedentary controls (n = 9), tumor-bearing (n = 9), exercised (n = 9), and tumor-bearing exercised (n = 10). Exercised and tumor-bearing exercised rats were exposed to resistance exercise of climbing a ladder apparatus with weights tied to their tails for 6 weeks. The physical activity of control and tumor-bearing rats was confined to the space of the cage. After this period, tumor-bearing and tumor-bearing exercised animals were inoculated subcutaneously with Walker-256 tumor cells (11.0 × 10 7 cells in 0.5 mL of phosphate-buffered saline) while control and exercised rats were injected with vehicle. Following inoculation, rats maintained resistance exercise training (exercised and tumor-bearing exercised) or sedentary behavior (control and tumor-bearing) for 12 more days, after which they were euthanized. Results showed muscle wasting in the tumor-bearing group, with body weight loss, increased systemic leukocytes, and inflammatory interleukins as well as muscular oxidative stress and reduced mTOR signaling. In contrast, RET in the tumor-bearing exercised group was able to mitigate the reduced body weight and muscle wasting with the attenuation of muscle oxidative stress and systemic inflammatory markers. RET also prevented loss of muscle strength associated with tumor development. RET, however, did not prevent the muscle proteolysis signaling via FBXO32 gene messenger RNA expression in the tumor-bearing group. In conclusion, RET performed prior tumor implantation prevents cachexia development by attenuating tumor-induced systemic pro-inflammatory condition with muscle oxidative stress and muscle damage.

  6. MUC16 provides immune protection by inhibiting synapse formation between NK and ovarian tumor cells

    Directory of Open Access Journals (Sweden)

    Migneault Martine

    2010-01-01

    Full Text Available Abstract Background Cancer cells utilize a variety of mechanisms to evade immune detection and attack. Effective immune detection largely relies on the formation of an immune synapse which requires close contact between immune cells and their targets. Here, we show that MUC16, a heavily glycosylated 3-5 million Da mucin expressed on the surface of ovarian tumor cells, inhibits the formation of immune synapses between NK cells and ovarian tumor targets. Our results indicate that MUC16-mediated inhibition of immune synapse formation is an effective mechanism employed by ovarian tumors to evade immune recognition. Results Expression of low levels of MUC16 strongly correlated with an increased number of conjugates and activating immune synapses between ovarian tumor cells and primary naïve NK cells. MUC16-knockdown ovarian tumor cells were more susceptible to lysis by primary NK cells than MUC16 expressing controls. This increased lysis was not due to differences in the expression levels of the ligands for the activating receptors DNAM-1 and NKG2D. The NK cell leukemia cell line (NKL, which does not express KIRs but are positive for DNAM-1 and NKG2D, also conjugated and lysed MUC16-knockdown cells more efficiently than MUC16 expressing controls. Tumor cells that survived the NKL challenge expressed higher levels of MUC16 indicating selective lysis of MUC16low targets. The higher csMUC16 levels on the NKL resistant tumor cells correlated with more protection from lysis as compared to target cells that were never exposed to the effectors. Conclusion MUC16, a carrier of the tumor marker CA125, has previously been shown to facilitate ovarian tumor metastasis and inhibits NK cell mediated lysis of tumor targets. Our data now demonstrates that MUC16 expressing ovarian cancer cells are protected from recognition by NK cells. The immune protection provided by MUC16 may lead to selective survival of ovarian cancer cells that are more efficient in

  7. Tumor cells and memory T cells converge at glycolysis

    Science.gov (United States)

    Karthikeyan, Swathi; Geschwind, Jean-Francois; Ganapathy-Kanniappan, Shanmugasundaram

    2014-01-01

    In the immune system, activation of naïve T (Tn) cells into effector T cells (Teff) involves a metabolic switch to glycolysis to promote rapid proliferation and differentiation. In the October issue of The Journal of Clinical Investigation, Sukumar et al. have demonstrated that in CD8+ memory T (Tems) cells glycolytic phenotype contributes to the shortened lifespan of Tems. Conversely, inhibition of glycolysis in Tems not only extended their viability but also augmented desirable properties. Notably, they also demonstrate that glycolytic inhibition during the ex vivo clonal expansion of tumor-specific Tems enhanced their antitumor function. Overall, the data suggest that an antiglycolytic strategy targeting the Tems could enhance antitumor immune response. On the other hand, cancer cells have long been known to exhibit metabolic reprogramming which involves a shift toward glycolysis (the conversion of glucose into lactate) to facilitate uninterrupted growth. Interestingly, antiglycolytic treatment of cancer cells has been known to trigger antitumor immune response as well. Taken together, it is probable that a strategy involving concurrent inhibition of glycolysis in tumor cells and Tems could promote a dual attack on cancer by inducing an effective antitumor immune response and an immunogenic chemotherapy. PMID:24556820

  8. Glycan Markers as Potential Immunological Targets in Circulating Tumor Cells.

    Science.gov (United States)

    Wang, Denong; Wu, Lisa; Liu, Xiaohe

    2017-01-01

    We present here an experimental approach for exploring a new class of tumor biomarkers that are overexpressed by circulating tumor cells (CTCs) and are likely targetable in immunotherapy against tumor metastasis. Using carbohydrate microarrays, anti-tumor monoclonal antibodies (mAbs) were scanned against a large panel of carbohydrate antigens to identify potential tumor glycan markers. Subsequently, flow cytometry and fiber-optic array scanning technology (FAST) were applied to determine whether the identified targets are tumor-specific cell-surface markers and are, therefore, likely suitable for targeted immunotherapy. Finally, the tumor glycan-specific antibodies identified were validated using cancer patients' blood samples for their performance in CTC-detection and immunotyping analysis. In this article, identifying breast CTC-specific glycan markers and targeting mAbs serve as examples to illustrate this tumor biomarker discovery strategy.

  9. Detection of T790M, the acquired resistance EGFR mutation, by tumor biopsy versus noninvasive blood-based analyses

    Science.gov (United States)

    Sundaresan, Tilak K.; Sequist, Lecia V.; Heymach, John V.; Riely, Gregory J.; Jänne, Pasi A.; Koch, Walter H.; Sullivan, James P.; Fox, Douglas B.; Maher, Robert; Muzikansky, Alona; Webb, Andrew; Tran, Hai T.; Giri, Uma; Fleisher, Martin; Yu, Helena A.; Wei, Wen; Johnson, Bruce E.; Barber, Thomas A.; Walsh, John R.; Engelman, Jeffrey A.; Stott, Shannon L.; Kapur, Ravi; Maheswaran, Shyamala; Toner, Mehmet

    2015-01-01

    Purpose The T790M gatekeeper mutation in the Epidermal Growth Factor Receptor (EGFR) is acquired by some EGFR-mutant non-small cell lung cancers (NSCLC) as they become resistant to selective tyrosine kinase inhibitors (TKIs). As third generation EGFR TKIs that overcome T790M-associated resistance become available, noninvasive approaches to T790M detection will become critical to guide management. Experimental Design As part of a multi-institutional Stand-Up-To-Cancer collaboration, we performed an exploratory analysis of 40 patients with EGFR-mutant tumors progressing on EGFR TKI therapy. We compared the T790M genotype from tumor biopsies with analysis of simultaneously collected circulating tumor cells (CTC) and circulating tumor DNA (ctDNA). Results T790M genotypes were successfully obtained in 30 (75%) tumor biopsies, 28 (70%) CTC samples and 32 (80%) ctDNA samples. The resistance-associated mutation was detected in 47–50% of patients using each of the genotyping assays, with concordance among them ranging from 57–74%. While CTC- and ctDNA-based genotyping were each unsuccessful in 20–30% of cases, the two assays together enabled genotyping in all patients with an available blood sample, and they identified the T790M mutation in 14 (35%) patients in whom the concurrent biopsy was negative or indeterminate. Conclusion Discordant genotypes between tumor biopsy and blood-based analyses may result from technological differences, as well as sampling different tumor cell populations. The use of complementary approaches may provide the most complete assessment of each patient’s cancer, which should be validated in predicting response to T790M-targeted inhibitors. PMID:26446944

  10. Importance of CD200 expression by tumor or host cells to regulation of immunotherapy in a mouse breast cancer model.

    Directory of Open Access Journals (Sweden)

    Anna Curry

    Full Text Available Cell-surface CD200 expression by mouse EMT6 breast tumor cells increased primary tumor growth and metastasis to the draining lymph nodes (DLN in normal (WT BALB/c female recipients, while lack of CD200R1 expression in a CD200R1-/- host negated this effect. Silencing CD200 expression in EMT6siCD200 tumor cells also reduced their ability to grow and metastasize in WT animals. The cellular mechanisms responsible for these effects have not been studied in detail. We report characterization of tumor infiltrating (TILs and draining lymph node (DLN cells in WT and CD200-/- BALB/c mice, receiving WT tumor cells, or EMT6 lacking CD200 expression (EMT6siCD200 cells. Our data show an important correlation with augmented CD8+ cytotoxic T cells and resistance to tumor growth in mice lacking exposure (on either host cells or tumor to the immunoregulatory molecule CD200. Confirmation of the importance of such CD8+ cells came from monitoring tumor growth and characterization of the TILs and DLN cells in WT mice challenged with EMT6 and EMT6siCD200 tumors and treated with CD8 and CD4 depleting antibodies. Finally, we have assessed the mechanisms(s whereby addition of metformin as an augmenting chemotherapeutic agent in CD200-/- animals given EMT6 tumors and treated with a previously established immunotherapy regime can increase host resistance. Our data support the hypothesis that increased autophagy in the presence of metformin increases CD8+ responses and tumor resistance, an effect attenuated by the autophagy inhibitor verteporfin.

  11. Dielectrophoretic capture and genetic analysis of single neuroblastoma tumor cells

    Directory of Open Access Journals (Sweden)

    Erica L Carpenter

    2014-07-01

    Full Text Available Our understanding of the diversity of cells that escape the primary tumor and seed micrometastases remains rudimentary, and approaches for studying circulating and disseminated tumor cells have been limited by low throughput and sensitivity, reliance on single parameter sorting, and a focus on enumeration rather than phenotypic and genetic characterization. Here we utilize a highly sensitive microfluidic and dielectrophoretic approach for the isolation and genetic analysis of individual tumor cells. We employed fluorescence labeling to isolate 208 single cells from spiking experiments conducted with 11 cell lines, including 8 neuroblastoma cell lines, and achieved a capture sensitivity of 1 tumor cell per 106 white blood cells. Sample fixation or freezing had no detectable effect on cell capture. Point mutations were accurately detected in the whole genome amplification product of captured single tumor cells but not in negative control white blood cells. We applied this approach to capture 144 single tumor cells from 10 bone marrow samples from patients suffering from neuroblastoma. In this pediatric malignancy, high-risk patients often exhibit wide-spread hematogenous metastasis, but access to primary tumor can be difficult or impossible. Here we used flow-based sorting to pre-enrich samples with tumor involvement below 0.02%. For all patients for whom a mutation in the Anaplastic Lymphoma Kinase gene had already been detected in their primary tumor, the same mutation was detected in single cells from their marrow. These findings demonstrate a novel, non-invasive, and adaptable method for the capture and genetic analysis of single tumor cells from cancer patients.

  12. Fatty acid synthase - Modern tumor cell biology insights into a classical oncology target.

    Science.gov (United States)

    Buckley, Douglas; Duke, Gregory; Heuer, Timothy S; O'Farrell, Marie; Wagman, Allan S; McCulloch, William; Kemble, George

    2017-09-01

    Decades of preclinical and natural history studies have highlighted the potential of fatty acid synthase (FASN) as a bona fide drug target for oncology. This review will highlight the foundational concepts upon which this perspective is built. Published studies have shown that high levels of FASN in patient tumor tissues are present at later stages of disease and this overexpression predicts poor prognosis. Preclinical studies have shown that experimental overexpression of FASN in previously normal cells leads to changes that are critical for establishing a tumor phenotype. Once the tumor phenotype is established, FASN elicits several changes to the tumor cell and becomes intertwined with its survival. The product of FASN, palmitate, changes the biophysical nature of the tumor cell membrane; membrane microdomains enable the efficient assembly of signaling complexes required for continued tumor cell proliferation and survival. Membranes densely packed with phospholipids containing saturated fatty acids become resistant to the action of other chemotherapeutic agents. Inhibiting FASN leads to tumor cell death while sparing normal cells, which do not have the dependence of this enzyme for normal functions, and restores membrane architecture to more normal properties thereby resensitizing tumors to killing by chemotherapies. One compound has recently reached clinical studies in solid tumor patients and highlights the need for continued evaluation of the role of FASN in tumor cell biology. Significant advances have been made and much remains to be done to optimally apply this class of pharmacological agents for the treatment of specific cancers. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  13. CT and MRI of germ-cell tumors with metastasis or multi-located tumors

    International Nuclear Information System (INIS)

    Miyagami, Mitsusuke; Tazoe, Makoto; Tsubokawa, Takashi

    1989-01-01

    Twenty-seven cases of germ-cell tumors were examined with a CT scan in our clinic. In the 11 cases of metastasis or multi-localized tumors, the CT findings were studied in connection with the MRI findings. There were 6 cases of germ-cell tumors which had broad infiltrating tumors with multiple lesions on first admission. Their tumor sites were different from that in cases of malignant glioma, being frequently localized in the pineal and/or the suprasellar region, on the wall of the third and/or lateral ventricle, and in the region of the basal ganglia. Five of the cases of germ-cell tumors had metastasis with various patterns connected to a remote area - that is, to spinal cords, to the ventricular wall and basal cistern of the brain stem by CSF dissemination, to a lung by hematogeneous metastasis, and to the peritoneal wall or organs by a V-P shunt. The CT findings of germ-cell tumors were correlated mainly with the results of the histological diagnosis; they were found not to differ with the tumor site. The germinoma in the suprasellar region had less calcification than in the pineal region. Cysts, calcification, and an enlargement of the lateral ventricle on the tumor side were frequently seen in the germinoma of the basal ganglia. On the MRI of 5 cases of germinoma, the T 1 -weighted image revealed a slightly low or iso signal intensity, while the T 2 -weighted image showed a high signal intensity. In the case of multiple tumor lesions, some cases demonstrated different CT findings and radiosensitivities for each tumor. The possibility of a multicentric origin for the tumors is thus suggested in some cases of germ-cell tumors. (author)

  14. Anti-tumor therapy with macroencapsulated endostatin producer cells.

    Science.gov (United States)

    Rodrigues, Danielle B; Chammas, Roger; Malavasi, Natália V; da Costa, Patrícia L N; Chura-Chambi, Rosa M; Balduino, Keli N; Morganti, Ligia

    2010-03-02

    Theracyte is a polytetrafluoroethylene membrane macroencapsulation system designed to induce neovascularization at the tissue interface, protecting the cells from host's immune rejection, thereby circumventing the problem of limited half-life and variation in circulating levels. Endostatin is a potent inhibitor of angiogenesis and tumor growth. Continuous delivery of endostatin improves the efficacy and potency of the antitumoral therapy. The purpose of this study was to determine whether recombinant fibroblasts expressing endostatin encapsulated in Theracyte immunoisolation devices can be used for delivery of this therapeutic protein for treatment of mice bearing B16F10 melanoma and Ehrlich tumors. Mice were inoculated subcutaneously with melanoma (B16F10 cells) or Ehrlich tumor cells at the foot pads. Treatment began when tumor thickness had reached 0.5 mm, by subcutaneous implantation of 107 recombinant encapsulated or non-encapsulated endostatin producer cells. Similar melanoma growth inhibition was obtained for mice treated with encapsulated or non-encapsulated endostatin-expressing cells. The treatment of mice bearing melanoma tumor with encapsulated endostatin-expressing cells was decreased by 50.0%, whereas a decrease of 56.7% in tumor thickness was obtained for mice treated with non-encapsulated cells. Treatment of Ehrlich tumor-bearing mice with non-encapsulated endostatin-expressing cells reduced tumor thickness by 52.4%, whereas lower tumor growth inhibition was obtained for mice treated with encapsulated endostatin-expressing cells: 24.2%. Encapsulated endostatin-secreting fibroblasts failed to survive until the end of the treatment. However, endostatin release from the devices to the surrounding tissues was confirmed by immunostaining. Decrease in vascular structures, functional vessels and extension of the vascular area were observed in melanoma microenvironments. This study indicates that immunoisolation devices containing endostatin

  15. Blood Outgrowth Endothelial Cells Increase Tumor Growth Rates and Modify Tumor Physiology: Relevance for Therapeutic Targeting

    Energy Technology Data Exchange (ETDEWEB)

    Pagan, Jonathan, E-mail: jdpagan@uams.edu; Przybyla, Beata; Jamshidi-Parsian, Azemat [Department of Radiation Oncology, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205 (United States); Gupta, Kalpna [Vascular Biology Center and Division of Hematology-Oncology Transplantation, Department of Medicine, University of Minnesota Medical School, MN 72223 (United States); Griffin, Robert J. [Department of Radiation Oncology, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72205 (United States)

    2013-02-18

    Endothelial cell precursors from human peripheral blood have been shown to home to areas of neovascularization and may assist tumor growth by increasing or fortifying blood vessel growth. In the present study, the influence of these cells on tumor growth and physiology was investigated and the role of these cells as a therapeutic target or in determining treatment sensitivity was tested. After isolation from human blood and expansion in vitro, actively growing cells with verified endothelial phenotype (Blood Outgrowth Endothelial Cell, BOEC) were injected i.v. into tumor bearing mice for three consecutive days. The growth rate was significantly enhanced in relatively small RERF human lung tumors (i.e., less than 150 mm{sup 3}) grown in immunocompromised mice by an average of 1.5-fold while it had no effect when injections were given to animals bearing larger tumors. There were no signs of toxicity or unwanted systemic effects. We also observed evidence of increased perfusion, vessel number, response to 15 Gy radiation and oxygenation in RERF tumors of animals injected with BOECs compared to control tumors. In addition, FSaII murine fibrosarcoma tumors were found to grow faster upon injection of BOECs. When FSaII tumors were subjected to a partial thermal ablation treatment using high intensity focused ultrasound (HIFU) there was consistently elevated detection of fluorescently labeled and i.v. injected endothelial precursors in the tumor when analyzed with optical imaging and/or histological preparations. Importantly, we also observed that BOECs treated with the novel anti-angiogenic peptide anginex in-vitro, show decreased proliferation and increased sensitivity to radiation. In vivo, the normal increase in FSaII tumor growth induced by injected BOECs was blunted by the addition of anginex treatment. It appears that endothelial precursors may significantly contribute to tumor vessel growth, tumor progression and/or repair of tumor damage and may improve the

  16. Blood Outgrowth Endothelial Cells Increase Tumor Growth Rates and Modify Tumor Physiology: Relevance for Therapeutic Targeting

    International Nuclear Information System (INIS)

    Pagan, Jonathan; Przybyla, Beata; Jamshidi-Parsian, Azemat; Gupta, Kalpna; Griffin, Robert J.

    2013-01-01

    Endothelial cell precursors from human peripheral blood have been shown to home to areas of neovascularization and may assist tumor growth by increasing or fortifying blood vessel growth. In the present study, the influence of these cells on tumor growth and physiology was investigated and the role of these cells as a therapeutic target or in determining treatment sensitivity was tested. After isolation from human blood and expansion in vitro, actively growing cells with verified endothelial phenotype (Blood Outgrowth Endothelial Cell, BOEC) were injected i.v. into tumor bearing mice for three consecutive days. The growth rate was significantly enhanced in relatively small RERF human lung tumors (i.e., less than 150 mm 3 ) grown in immunocompromised mice by an average of 1.5-fold while it had no effect when injections were given to animals bearing larger tumors. There were no signs of toxicity or unwanted systemic effects. We also observed evidence of increased perfusion, vessel number, response to 15 Gy radiation and oxygenation in RERF tumors of animals injected with BOECs compared to control tumors. In addition, FSaII murine fibrosarcoma tumors were found to grow faster upon injection of BOECs. When FSaII tumors were subjected to a partial thermal ablation treatment using high intensity focused ultrasound (HIFU) there was consistently elevated detection of fluorescently labeled and i.v. injected endothelial precursors in the tumor when analyzed with optical imaging and/or histological preparations. Importantly, we also observed that BOECs treated with the novel anti-angiogenic peptide anginex in-vitro, show decreased proliferation and increased sensitivity to radiation. In vivo, the normal increase in FSaII tumor growth induced by injected BOECs was blunted by the addition of anginex treatment. It appears that endothelial precursors may significantly contribute to tumor vessel growth, tumor progression and/or repair of tumor damage and may improve the

  17. Cisplatin as an Anti-Tumor Drug: Cellular Mechanisms of Activity, Drug Resistance and Induced Side Effects

    International Nuclear Information System (INIS)

    Florea, Ana-Maria; Büsselberg, Dietrich

    2011-01-01

    Platinum complexes are clinically used as adjuvant therapy of cancers aiming to induce tumor cell death. Depending on cell type and concentration, cisplatin induces cytotoxicity, e.g., by interference with transcription and/or DNA replication mechanisms. Additionally, cisplatin damages tumors via induction of apoptosis, mediated by the activation of various signal transduction pathways, including calcium signaling, death receptor signaling, and the activation of mitochondrial pathways. Unfortunately, neither cytotoxicity nor apoptosis are exclusively induced in cancer cells, thus, cisplatin might also lead to diverse side-effects such as neuro- and/or renal-toxicity or bone marrow-suppression. Moreover, the binding of cisplatin to proteins and enzymes may modulate its biochemical mechanism of action. While a combination-chemotherapy with cisplatin is a cornerstone for the treatment of multiple cancers, the challenge is that cancer cells could become cisplatin-resistant. Numerous mechanisms of cisplatin resistance were described including changes in cellular uptake, drug efflux, increased detoxification, inhibition of apoptosis and increased DNA repair. To minimize cisplatin resistance, combinatorial therapies were developed and have proven more effective to defeat cancers. Thus, understanding of the biochemical mechanisms triggered by cisplatin in tumor cells may lead to the design of more efficient platinum derivates (or other drugs) and might provide new therapeutic strategies and reduce side effects

  18. Cisplatin as an Anti-Tumor Drug: Cellular Mechanisms of Activity, Drug Resistance and Induced Side Effects

    Energy Technology Data Exchange (ETDEWEB)

    Florea, Ana-Maria [Department of Neuropathology, Heinrich-Heine University, Düsseldorf (Germany); Büsselberg, Dietrich, E-mail: dib2015@qatar-med.cornell.edu [Weil Cornell Medical College in Qatar, Qatar Foundation-Education City, P.O. Box 24144, Doha (Qatar)

    2011-03-15

    Platinum complexes are clinically used as adjuvant therapy of cancers aiming to induce tumor cell death. Depending on cell type and concentration, cisplatin induces cytotoxicity, e.g., by interference with transcription and/or DNA replication mechanisms. Additionally, cisplatin damages tumors via induction of apoptosis, mediated by the activation of various signal transduction pathways, including calcium signaling, death receptor signaling, and the activation of mitochondrial pathways. Unfortunately, neither cytotoxicity nor apoptosis are exclusively induced in cancer cells, thus, cisplatin might also lead to diverse side-effects such as neuro- and/or renal-toxicity or bone marrow-suppression. Moreover, the binding of cisplatin to proteins and enzymes may modulate its biochemical mechanism of action. While a combination-chemotherapy with cisplatin is a cornerstone for the treatment of multiple cancers, the challenge is that cancer cells could become cisplatin-resistant. Numerous mechanisms of cisplatin resistance were described including changes in cellular uptake, drug efflux, increased detoxification, inhibition of apoptosis and increased DNA repair. To minimize cisplatin resistance, combinatorial therapies were developed and have proven more effective to defeat cancers. Thus, understanding of the biochemical mechanisms triggered by cisplatin in tumor cells may lead to the design of more efficient platinum derivates (or other drugs) and might provide new therapeutic strategies and reduce side effects.

  19. Malignant primary germ-cell tumor of the brain

    International Nuclear Information System (INIS)

    Yamamoto, Toyoshiro; Sato, Shinichi; Nakao, Satoshi; Ban, Sadahiko; Namba, Koh

    1983-01-01

    The unusual case of a 15 year old boy with three discrete paraventricular germ-cell tumors is reported.FThe first tumor was located just lateral to the left thalamus and included a massive cystic part around it, the second tumor in the paraventricular region above the head of the left caudate nucleus and the third tumor in the medial part of the left parietal lobe.FTotal removal of all tumors was successfully accomplished in stages at four separate operations, namely, the first tumor was removed through the left transsylvian approach, the second tumor via left superior frontal gyrus and the third tumor via left superior frontal gyrus and left superior parietal lobule.FHistological examination revealed that the first tumor was teratoma, the second was choriocarcinoma and the third was germinoma.FPrimary germ-cell tumors of the brain can be divided into 5 groups: 1) germinoma; 2) embryonal carcinoma; 3) choriocarcinoma; 4) yolk-sac tumor; or 5) teratoma.FIn this case, a combination of three different histological patterns was seen. If malignant germ-cell tumor is supected on CT, aggressive extirpation should be done, not only to determine the exact diagnosis, but also to provide the basis for subsequent adjunctive therapy. (author)

  20. Migratory neighbors and distant invaders: tumor-associated niche cells

    Science.gov (United States)

    Wels, Jared; Kaplan, Rosandra N.; Rafii, Shahin; Lyden, David

    2008-01-01

    The cancer environment is comprised of tumor cells as well as a wide network of stromal and vascular cells participating in the cellular and molecular events necessary for invasion and metastasis. Tumor secretory factors can activate the migration of host cells, both near to and far from the primary tumor site, as well as promote the exodus of cells to distant tissues. Thus, the migration of stromal cells and tumor cells among specialized microenvironments takes place throughout tumor and metastatic progression, providing evidence for the systemic nature of a malignancy. Investigations of the tumor–stromal and stromal–stromal cross-talk involved in cellular migration in cancer may lead to the design of novel therapeutic strategies. PMID:18316475

  1. Human CD34+ cells engineered to express membrane-bound tumor necrosis factor-related apoptosis-inducing ligand target both tumor cells and tumor vasculature.

    Science.gov (United States)

    Lavazza, Cristiana; Carlo-Stella, Carmelo; Giacomini, Arianna; Cleris, Loredana; Righi, Marco; Sia, Daniela; Di Nicola, Massimo; Magni, Michele; Longoni, Paolo; Milanesi, Marco; Francolini, Maura; Gloghini, Annunziata; Carbone, Antonino; Formelli, Franca; Gianni, Alessandro M

    2010-03-18

    Adenovirus-transduced CD34+ cells expressing membrane-bound tumor necrosis factor-related apoptosis-inducing ligand (CD34-TRAIL+ cells) exert potent antitumor activity. To further investigate the mechanism(s) of action of CD34-TRAIL+ cells, we analyzed their homing properties as well as antitumor and antivascular effects using a subcutaneous myeloma model in immunodeficient mice. After intravenous injection, transduced cells homed in the tumor peaking at 48 hours when 188 plus or minus 25 CD45+ cells per 10(5) tumor cells were detected. Inhibition experiments showed that tumor homing of CD34-TRAIL+ cells was largely mediated by vascular cell adhesion molecule-1 and stromal cell-derived factor-1. Both CD34-TRAIL+ cells and soluble (s)TRAIL significantly reduced tumor volume by 40% and 29%, respectively. Computer-aided analysis of TdT-mediated dUTP nick end-labeling-stained tumor sections demonstrated significantly greater effectiveness for CD34-TRAIL+ cells in increasing tumor cell apoptosis and necrosis over sTRAIL. Proteome array analysis indicated that CD34-TRAIL+ cells and sTRAIL activate similar apoptotic machinery. In vivo staining of tumor vasculature with sulfosuccinimidyl-6-(biotinamido) hexanoate-biotin revealed that CD34-TRAIL+ cells but not sTRAIL significantly damaged tumor vasculature, as shown by TdT-mediated dUTP nick end-labeling+ endothelial cells, appearance of hemorrhagic areas, and marked reduction of endothelial area. These results demonstrate that tumor homing of CD34-TRAIL+ cells induces early vascular disruption, resulting in hemorrhagic necrosis and tumor destruction.

  2. Therapeutic efficacy of interleukin-2 activated killer cells against adriamycin resistant mouse B16-BL6 melanoma.

    Science.gov (United States)

    Gautam, S C; Chikkala, N F; Lewis, I; Grabowski, D R; Finke, J H; Ganapathi, R

    1992-01-01

    Development of multidrug-resistance (MDR) remains a major cause of failure in the treatment of cancer with chemotherapeutic agents. In our efforts to explore alternative treatment regimens for multidrug-resistant tumors we have examined the sensitivity of MDR tumor cell lines to lymphokine activated killer (LAK) cells. Adriamycin (ADM) resistant B16-BL6 melanoma, L1210 and P388 leukemic cell lines were tested for sensitivity to lysis by LAK cells in vitro. While ADM-resistant B16-BL6 and L1210 sublines were found to exhibit at least 2-fold greater susceptibility to lysis by LAK cells, sensitivity of ADM-resistant P388 cell was similar to that of parental cells. Since ADM-resistant B16-BL6 cells were efficiently lysed by LAK cells in vitro, the efficacy of therapy with LAK cells against the ADM-resistant B16-BL6 subline in vivo was evaluated. Compared to mice bearing parental B16-BL6 tumor cells, the adoptive transfer of LAK cells and rIL2 significantly reduced formation of experimental metastases (P less than 0.009) and extended median survival time (P less than 0.001) of mice bearing ADM-resistant B16-BL6 tumor cells. Results suggest that immunotherapy with LAK cells and rIL2 may be a useful modality in the treatment of cancers with the MDR phenotype.

  3. Bcl-2 inhibitors potentiate the cytotoxic effects of radiation in Bcl-2 overexpressing radioresistant tumor cells

    International Nuclear Information System (INIS)

    Hara, Takamitsu; Omura-Minamisawa, Motoko; Chao Cheng; Nakagami, Yoshihiro; Ito, Megumi; Inoue, Tomio

    2005-01-01

    Purpose: Bcl-2, an inhibitor of apoptosis frequently shows elevated expression in human tumors, thus resulting in resistance to radiation therapy. Therefore, inhibiting Bcl-2 function may enhance the radiosensitivity of tumor cells. Tetrocarcin A (TC-A) and bcl-2 antisense oligonucleotides exhibit antitumor activity by inhibiting Bcl-2 function and transcription, respectively. We investigated whether these antitumor agents would enhance the cytotoxic effects of radiation in tumor cells overexpressing Bcl-2. Methods and materials: We used HeLa/bcl-2 cells, a stable Bcl-2-expressing cell line derived from wild-type HeLa (HeLa/wt) cells. Cells were incubated with TC-A and bcl-2 antisense oligonucleotides for 24 h after irradiation, and cell viability was then determined. Apoptotic cells were quantified by flow cytometric assay. Results: The HeLa/bcl-2 cells were more resistant to radiation than HeLa/wt cells. At concentrations that are not inherently cytotoxic, both TC-A and bcl-2 antisense oligonucleotides increased the cytotoxic effects of radiation in HeLa/bcl-2 cells, but not in HeLa/wt cells. However, in HeLa/bcl-2 cells, additional treatment with TC-A in combination with radiation did not significantly increase apoptosis. Conclusions: The present results suggest that TC-A and bcl-2 antisense oligonucleotides reduce radioresistance of tumor cells overexpressing Bcl-2. Therefore, a combination of radiotherapy and Bcl-2 inhibitors may prove to be a useful therapeutic approach for treating tumors that overexpress Bcl-2

  4. Tumor Cells and Tumor-Associated Macrophages: Secreted Proteins as Potential Targets for Therapy

    Science.gov (United States)

    Baay, Marc; Brouwer, Anja; Pauwels, Patrick; Peeters, Marc; Lardon, Filip

    2011-01-01

    Inflammatory pathways, meant to defend the organism against infection and injury, as a byproduct, can promote an environment which favors tumor growth and metastasis. Tumor-associated macrophages (TAMs), which constitute a significant part of the tumor-infiltrating immune cells, have been linked to the growth, angiogenesis, and metastasis of a variety of cancers, most likely through polarization of TAMs to the M2 (alternative) phenotype. The interaction between tumor cells and macrophages provides opportunities for therapy. This paper will discuss secreted proteins as targets for intervention. PMID:22162712

  5. Tumor Cells and Tumor-Associated Macrophages: Secreted Proteins as Potential Targets for Therapy

    Directory of Open Access Journals (Sweden)

    Marc Baay

    2011-01-01

    Full Text Available Inflammatory pathways, meant to defend the organism against infection and injury, as a byproduct, can promote an environment which favors tumor growth and metastasis. Tumor-associated macrophages (TAMs, which constitute a significant part of the tumor-infiltrating immune cells, have been linked to the growth, angiogenesis, and metastasis of a variety of cancers, most likely through polarization of TAMs to the M2 (alternative phenotype. The interaction between tumor cells and macrophages provides opportunities for therapy. This paper will discuss secreted proteins as targets for intervention.

  6. Residual tumor cells that drive disease relapse after chemotherapy do not have enhanced tumor initiating capacity.

    Directory of Open Access Journals (Sweden)

    Ganapati V Hegde

    Full Text Available Although chemotherapy is used to treat most advanced solid tumors, recurrent disease is still the major cause of cancer-related mortality. Cancer stem cells (CSCs have been the focus of intense research in recent years because they provide a possible explanation for disease relapse. However, the precise role of CSCs in recurrent disease remains poorly understood and surprisingly little attention has been focused on studying the cells responsible for re-initiating tumor growth within the original host after chemotherapy treatment. We utilized both xenograft and genetically engineered mouse models of non-small cell lung cancer (NSCLC to characterize the residual tumor cells that survive chemotherapy treatment and go on to cause tumor regrowth, which we refer to as tumor re-initiating cells (TRICs. We set out to determine whether TRICs display characteristics of CSCs, and whether assays used to define CSCs also provide an accurate readout of a cell's ability to cause tumor recurrence. We did not find consistent enrichment of CSC marker positive cells or enhanced tumor initiating potential in TRICs. However, TRICs from all models do appear to be in EMT, a state that has been linked to chemoresistance in numerous types of cancer. Thus, the standard CSC assays may not accurately reflect a cell's ability to drive disease recurrence.

  7. Intensive chemotherapy as salvage treatment for solid tumors: focus on germ cell cancer

    Energy Technology Data Exchange (ETDEWEB)

    Selle, F.; Gligorov, J. [Medical Oncology and Cellular Therapy Department, Hospital Tenon, Public Assistance Hospitals of Paris, Alliance for Cancer Research (APREC), Paris (France); Pierre & Marie Curie University (UPMC Paris VI), Paris (France); Richard, S.; Khalil, A. [Medical Oncology and Cellular Therapy Department, Hospital Tenon, Public Assistance Hospitals of Paris, Alliance for Cancer Research (APREC), Paris (France); Alexandre, I. [Medical Oncology Department, Hospital Centre of Bligny, Briis-sous-Forges (France); Avenin, D.; Provent, S.; Soares, D.G. [Medical Oncology and Cellular Therapy Department, Hospital Tenon, Public Assistance Hospitals of Paris, Alliance for Cancer Research (APREC), Paris (France); Lotz, J.P. [Medical Oncology and Cellular Therapy Department, Hospital Tenon, Public Assistance Hospitals of Paris, Alliance for Cancer Research (APREC), Paris (France); Pierre & Marie Curie University (UPMC Paris VI), Paris (France)

    2014-11-04

    Germ cell tumors present contrasting biological and molecular features compared to many solid tumors, which may partially explain their unusual sensitivity to chemotherapy. Reduced DNA repair capacity and enhanced induction of apoptosis appear to be key factors in the sensitivity of germ cell tumors to cisplatin. Despite substantial cure rates, some patients relapse and subsequently die of their disease. Intensive doses of chemotherapy are used to counter mechanisms of drug resistance. So far, high-dose chemotherapy with hematopoietic stem cell support for solid tumors is used only in the setting of testicular germ cell tumors. In that indication, high-dose chemotherapy is given as the first or late salvage treatment for patients with either relapsed or progressive tumors after initial conventional salvage chemotherapy. High-dose chemotherapy is usually given as two or three sequential cycles using carboplatin and etoposide with or without ifosfamide. The administration of intensive therapy carries significant side effects and can only be efficiently and safely conducted in specialized referral centers to assure optimum patient care outcomes. In breast and ovarian cancer, most studies have demonstrated improvement in progression-free survival (PFS), but overall survival remained unchanged. Therefore, most of these approaches have been dropped. In germ cell tumors, clinical trials are currently investigating novel therapeutic combinations and active treatments. In particular, the integration of targeted therapies constitutes an important area of research for patients with a poor prognosis.

  8. Intensive chemotherapy as salvage treatment for solid tumors: focus on germ cell cancer

    International Nuclear Information System (INIS)

    Selle, F.; Gligorov, J.; Richard, S.; Khalil, A.; Alexandre, I.; Avenin, D.; Provent, S.; Soares, D.G.; Lotz, J.P.

    2014-01-01

    Germ cell tumors present contrasting biological and molecular features compared to many solid tumors, which may partially explain their unusual sensitivity to chemotherapy. Reduced DNA repair capacity and enhanced induction of apoptosis appear to be key factors in the sensitivity of germ cell tumors to cisplatin. Despite substantial cure rates, some patients relapse and subsequently die of their disease. Intensive doses of chemotherapy are used to counter mechanisms of drug resistance. So far, high-dose chemotherapy with hematopoietic stem cell support for solid tumors is used only in the setting of testicular germ cell tumors. In that indication, high-dose chemotherapy is given as the first or late salvage treatment for patients with either relapsed or progressive tumors after initial conventional salvage chemotherapy. High-dose chemotherapy is usually given as two or three sequential cycles using carboplatin and etoposide with or without ifosfamide. The administration of intensive therapy carries significant side effects and can only be efficiently and safely conducted in specialized referral centers to assure optimum patient care outcomes. In breast and ovarian cancer, most studies have demonstrated improvement in progression-free survival (PFS), but overall survival remained unchanged. Therefore, most of these approaches have been dropped. In germ cell tumors, clinical trials are currently investigating novel therapeutic combinations and active treatments. In particular, the integration of targeted therapies constitutes an important area of research for patients with a poor prognosis

  9. An Effective Approach for Immunotherapy Using Irradiated Tumor Cells

    International Nuclear Information System (INIS)

    Mostafa, D.M.B.

    2011-01-01

    This study has been aimed to investigate the effect of injection of Irradiated Ehrlich tumor cells alone or concurrent with immunomodulator in mice before and after challenge with viable Ehrlich tumor cells for enhancement of immune system. This study includes the estimation of survival, tumor size, lymphocyte count, LDH, MTT, granzyme B, and DNA fragmentation. In order to fulfill the target of this study, a total of 120 female swiss albino mice were used. They were divided into two classes vaccinated (injection of vaccine before challenge) and therapeutic class (injection of vaccine after challenge). Each class was divided into four groups, group (1) mice injected with viable Ehrlich tumor cells (G1), group (2) mice injected with irradiated tumor cells (G2), group (3) mice injected with immunomodulator (G3), and group (4) mice injected with irradiated tumor cells + immunomodulator (G4). Results obtained from this study demonstrated that, the lymphocyte count and granzyme B activity were increased in both the vaccinated and therapeutic classes compared with control group. LDH activity was decreased in all groups of vaccinated class and also in G2 and G4 groups of therapeutic class compared with control group. There was a significant increase in percent apoptosis of tumor cells cultured with spleenocytes of the groups of vaccinated class as compared with control group. Cellular DNA from Ehrlich tumor cell line cultured with spleenocytes of immunized groups was fragmented into discrete bands of approximate multiples of 200 bp. Revealing significant apoptosis in tumor cells due to vaccination. It is concluded that, vaccination with irradiated tumor cells is an effective approach in stimulation of immune system against viable tumor cells.

  10. Antigen localization controls T cell-mediated tumor immunity.

    Science.gov (United States)

    Zeelenberg, Ingrid S; van Maren, Wendy W C; Boissonnas, Alexandre; Van Hout-Kuijer, Maaike A; Den Brok, Martijn H M G M; Wagenaars, Jori A L; van der Schaaf, Alie; Jansen, Eric J R; Amigorena, Sebastian; Théry, Clotilde; Figdor, Carl G; Adema, Gosse J

    2011-08-01

    Effective antitumor immunotherapy requires the identification of suitable target Ags. Interestingly, many of the tumor Ags used in clinical trials are present in preparations of secreted tumor vesicles (exosomes). In this study, we compared T cell responses elicited by murine MCA101 fibrosarcoma tumors expressing a model Ag at different localizations within the tumor cell in association with secreted vesicles (exosomes), as a nonsecreted cell-associated protein, or as secreted soluble protein. Remarkably, we demonstrated that only the tumor-secreting vesicle-bound Ag elicited a strong Ag-specific CD8(+) T cell response, CD4(+) T cell help, Ag-specific Abs, and a decrease in the percentage of immunosuppressive regulatory T cells in the tumor. Moreover, in a therapeutic tumor model of cryoablation, only in tumors secreting vesicle-bound Ag could Ag-specific CD8(+) T cells still be detected up to 16 d after therapy. We concluded that the localization of an Ag within the tumor codetermines whether a robust immunostimulatory response is elicited. In vivo, vesicle-bound Ag clearly skews toward a more immunogenic phenotype, whereas soluble or cell-associated Ag expression cannot prevent or even delay outgrowth and results in tumor tolerance. This may explain why particular immunotherapies based on these vesicle-bound tumor Ags are potentially successful. Therefore, we conclude that this study may have significant implications in the discovery of new tumor Ags suitable for immunotherapy and that their location should be taken into account to ensure a strong antitumor immune response.

  11. A Rare Cause of Prepubertal Gynecomastia: Sertoli Cell Tumor

    Directory of Open Access Journals (Sweden)

    Fatma Dursun

    2015-01-01

    Full Text Available Prepubertal gynecomastia due to testis tumors is a very rare condition. Nearly 5% of the patients with testicular mass present with gynecomastia. Sertoli cell tumors are sporadic in 60% of the reported cases, while the remaining is a component of multiple neoplasia syndromes such as Peutz-Jeghers syndrome and Carney complex. We present a 4-year-old boy with gynecomastia due to Sertoli cell tumor with no evidence of Peutz-Jeghers syndrome or Carney complex.

  12. Treatment Options By Stage (Ovarian Germ Cell Tumors)

    Science.gov (United States)

    ... Germ Cell Tumors Treatment (PDQ®)–Patient Version Treatment Option Overview Go to Health Professional Version Key Points ... and restore) the body’s blood cells. New treatment options Combination chemotherapy (the use of more than one ...

  13. Selective Killing of Prostate Tumor Cells by Cytocidal Viruses

    National Research Council Canada - National Science Library

    Lyles, Douglas

    2003-01-01

    .... The novelty in our approach is our ability to enhance the selectivity of killing of tumor cells versus normal cells by manipulating the viral genes that control the antiviral interferon response...

  14. Selective Killing of Prostate Tumor Cells by Cytocidal Viruses

    National Research Council Canada - National Science Library

    Lyles, Douglas

    2004-01-01

    .... The novelty in our approach is our ability to enhance the selectivity of killing of tumor cells versus normal cells by manipulating the viral genes that control the antiviral interferon response...

  15. Selective Killing of Prostate Tumor Cells by Cytocidal Viruses

    National Research Council Canada - National Science Library

    Lyles, Douglas S

    2005-01-01

    ...). The novelty in our approach is our ability to enhance the selectivity of VSV-induced killing of tumor cells versus normal cells by manipulating the viral genes that control the antiviral interferon response...

  16. Large mid-esophageal granular cell tumor: benign versus malignant

    Directory of Open Access Journals (Sweden)

    Prarthana Roselil Christopher

    2015-06-01

    Full Text Available Granular cell tumors are rare soft tissue neoplasms, among which only 2% are malignant, arising from nervous tissue. Here we present a case of a large esophageal granular cell tumor with benign histopathological features which metastasized to the liver, but showing on positron emission tomography-computerized tomography standardized uptake value suggestive of a benign lesion.

  17. Maternal smoking and testicular germ cell tumors.

    Science.gov (United States)

    McGlynn, Katherine A; Zhang, Yawei; Sakoda, Lori C; Rubertone, Mark V; Erickson, Ralph L; Graubard, Barry I

    2006-10-01

    Testicular germ cell tumors (TGCT) are the most common cancer among men ages 15 to 35 years in the United States. The well-established TGCT risk factors cryptorchism, prior diagnosis of TGCT, and family history of testicular cancer indicate that exposures in early life and/or in the familial setting may be critical to determining risk. Previous reports of familial clustering of lung cancer in mothers and testicular cancers in sons suggest that passive smoking in childhood may be such an exposure. To clarify the relationship of passive smoking exposure to TGCT risk, data from 754 cases and 928 controls enrolled in the Servicemen's Testicular Tumor Environmental and Endocrine Determinants study were analyzed. Data from 1,086 mothers of the cases and controls were also examined. Overall, there was no relationship between maternal [odds ratio (OR), 1.1; 95% confidence interval (95% CI), 0.9-1.3] or paternal smoking (OR, 1.0; 95% CI, 0.8-1.3) and TGCT risk. Although living with a non-parent smoker was marginally related to risk (OR, 1.4; 95% CI, 1.0-2.1), there was no relationship with number of smokers, amount smoked, or duration of smoking. Responses from both case-control participants and mothers also revealed no relationship between either maternal smoking while pregnant or while breast-feeding. Results did not differ by TGCT histology (seminoma, non-seminoma). These results do not support the hypothesis that passive smoking, either in utero or in childhood, is related to risk of TGCT. Other early life exposures, however, may explain the familial clustering of lung cancer in mothers and TGCT in sons.

  18. An activated form of ADAM10 is tumor selective and regulates cancer stem-like cells and tumor growth

    Science.gov (United States)

    Saha, Nayanendu; Eissman, Moritz F.; Xu, Kai; Llerena, Carmen; Kusebauch, Ulrike; Ding, Bi-Sen; Cao, Zhongwei; Rafii, Shahin; Ernst, Matthias; Scott, Andrew M.; Nikolov, Dimitar B.; Lackmann, Martin

    2016-01-01

    The transmembrane metalloprotease ADAM10 sheds a range of cell surface proteins, including ligands and receptors of the Notch, Eph, and erbB families, thereby activating signaling pathways critical for tumor initiation and maintenance. ADAM10 is thus a promising therapeutic target. Although widely expressed, its activity is normally tightly regulated. We now report prevalence of an active form of ADAM10 in tumors compared with normal tissues, in mouse models and humans, identified by our conformation-specific antibody mAb 8C7. Structure/function experiments indicate mAb 8C7 binds an active conformation dependent on disulfide isomerization and oxidative conditions, common in tumors. Moreover, this active ADAM10 form marks cancer stem-like cells with active Notch signaling, known to mediate chemoresistance. Importantly, specific targeting of active ADAM10 with 8C7 inhibits Notch activity and tumor growth in mouse models, particularly regrowth after chemotherapy. Our results indicate targeted inhibition of active ADAM10 as a potential therapy for ADAM10-dependent tumor development and drug resistance. PMID:27503072

  19. Effect of misonidazole on radiosensitivity of Ehrlich ascites tumor cells

    International Nuclear Information System (INIS)

    Takeuchi, Hiroshi

    1986-01-01

    The effect of Misonidazole on radiosensitivity of Ehrlich ascites tumor cells was studied in vivo. Ehrlich ascites tumor cells growing intraperitoneally (ICR/SIC mice) for either 1, 4, 6 or 10 days were irradiated in vivo (whole body irradiation) with or without Misonidazole. Immediately after irradiation tumor cells were transplanted intraperitoneally into new animals. Four days later, the propagated surviving cells were removed and counted for analyses. Enhancement ratio of Misonidazole at the surviving fraction of 0.1 were 1.0 (for 1-day-old), 1.3 (for 4-day-old), 1.9 (for 6-day-old), 1.9 (for 10-day-old) and 2.8 (for anoxic cells) respectively. The gradual increase of the enhancement ratio of the ascites tumore cells during intraperitoneal growth from 1 through 10 days might be attributed to an increase of hypoxic tumor cells. Cytotoxicity was not observed at 0.1 mg per gram body weight of Misonidazole but was at 1 mg per gram body weight of Misonidazole in 6-day-old and 10-day-old Ehrlich ascites tumor cells which were supposed to contain hypoxic cells. These results suggest that Misonidazole may prove an effective radiosensitizer for hypoxic tumor cells. (author)

  20. Targeting Mitochondrial Function to Treat Quiescent Tumor Cells in Solid Tumors

    Directory of Open Access Journals (Sweden)

    Xiaonan Zhang

    2015-11-01

    Full Text Available The disorganized nature of tumor vasculature results in the generation of microenvironments characterized by nutrient starvation, hypoxia and accumulation of acidic metabolites. Tumor cell populations in such areas are often slowly proliferating and thus refractory to chemotherapeutical drugs that are dependent on an active cell cycle. There is an urgent need for alternative therapeutic interventions that circumvent growth dependency. The screening of drug libraries using multicellular tumor spheroids (MCTS or glucose-starved tumor cells has led to the identification of several compounds with promising therapeutic potential and that display activity on quiescent tumor cells. Interestingly, a common theme of these drug screens is the recurrent identification of agents that affect mitochondrial function. Such data suggest that, contrary to the classical Warburg view, tumor cells in nutritionally-compromised microenvironments are dependent on mitochondrial function for energy metabolism and survival. These findings suggest that mitochondria may represent an “Achilles heel” for the survival of slowly-proliferating tumor cells and suggest strategies for the development of therapy to target these cell populations.

  1. Cell shunt resistance and photovoltaic module performance

    Energy Technology Data Exchange (ETDEWEB)

    McMahon, T.J.; Basso, T.S.; Rummel, S.R. [National Renewable Energy Lab., Golden, CO (United States)

    1996-05-01

    Shunt resistance of cells in photovoltaic modules can affect module power output and could indicate flawed manufacturing processes and reliability problems. The authors describe a two-terminal diagnostic method to directly measure the shunt resistance of individual cells in a series-connected module non-intrusively, without deencapsulation. Peak power efficiency vs. light intensity was measured on a 12-cell, series-connected, single crystalline module having relatively high cell shunt resistances. The module was remeasured with 0.5-, 1-, and 2-ohm resistors attached across each cell to simulate shunt resistances of several emerging technologies. Peak power efficiencies decreased dramatically at lower light levels. Using the PSpice circuit simulator, the authors verified that cell shunt and series resistances can indeed be responsible for the observed peak power efficiency vs. intensity behavior. The authors discuss the effect of basic cell diode parameters, i.e., shunt resistance, series resistance, and recombination losses, on PV module performance as a function of light intensity.

  2. Tumor-Induced Generation of Splenic Erythroblast-like Ter-Cells Promotes Tumor Progression.

    Science.gov (United States)

    Han, Yanmei; Liu, Qiuyan; Hou, Jin; Gu, Yan; Zhang, Yi; Chen, Zhubo; Fan, Jia; Zhou, Weiping; Qiu, Shuangjian; Zhang, Yonghong; Dong, Tao; Li, Ning; Jiang, Zhengping; Zhu, Ha; Zhang, Qian; Ma, Yuanwu; Zhang, Lianfeng; Wang, Qingqing; Yu, Yizhi; Li, Nan; Cao, Xuetao

    2018-04-19

    Identifying tumor-induced leukocyte subsets and their derived circulating factors has been instrumental in understanding cancer as a systemic disease. Nevertheless, how primary tumor-induced non-leukocyte populations in distal organs contribute to systemic spread remains poorly defined. Here, we report one population of tumor-inducible, erythroblast-like cells (Ter-cells) deriving from megakaryocyte-erythroid progenitor cells with a unique Ter-119 + CD45 - CD71 + phenotype. Ter-cells are enriched in the enlarged spleen of hosts bearing advanced tumors and facilitate tumor progression by secreting neurotrophic factor artemin into the blood. Transforming growth factor β (TGF-β) and Smad3 activation are important in Ter-cell generation. In vivo blockade of Ter-cell-derived artemin inhibits hepatocellular carcinoma (HCC) growth, and artemin deficiency abolishes Ter-cells' tumor-promoting ability. We confirm the presence of splenic artemin-positive Ter-cells in human HCC patients and show that significantly elevated serum artemin correlates with poor prognosis. We propose that Ter-cells and the secreted artemin play important roles in cancer progression with prognostic and therapeutic implications. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. Indirubin inhibits cell proliferation, migration, invasion and angiogenesis in tumor-derived endothelial cells

    Directory of Open Access Journals (Sweden)

    Li Z

    2018-05-01

    Full Text Available Zhuohong Li, Chaofu Zhu, Baiping An, Yu Chen, Xiuyun He, Lin Qian, Lan Lan, Shijie Li Department of Oncology, The Affiliated Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China Purpose: Hepatocellular carcinoma is one of the most predominant malignancies with high fatality rate and its incidence is rising at an alarming rate because of its resistance to radio- and chemotherapy. Indirubin is the major active anti-tumor ingredient of a traditional Chinese herbal medicine. The present study aimed to analyze the effects of indirubin on cell proliferation, migration, invasion, and angiogenesis of tumor-derived endothelial cells (Td-EC. Methods: Td-EC were derived from human umbilical vein endothelial cells (HUVEC by treating HUVEC with the conditioned medium of human liver cancer cell line HepG2. Cell proliferation, migration, invasion, and angiogenesis were assessed by MTT, wound healing, in vitro cell invasion, and in vitro tube formation assay. Results: Td-EC were successfully obtained from HUVEC cultured with 50% culture supernatant from serum-starved HepG2 cells. Indirubin significantly inhibited Td-EC proliferation in a dose- and time-dependent manner. Indirubin also inhibited Td-EC migration, invasion, and angiogenesis. However, indirubin’s effects were weaker on HUVEC than Td-EC. Conclusion: Indirubin significantly inhibited Td-EC proliferation, migration, invasion, and angiogenesis. Keywords: indirubin, Td-EC, proliferation, migration, invasion, angiogenesis

  4. [Isolation and identification of brain tumor stem cells from human brain neuroepithelial tumors].

    Science.gov (United States)

    Fang, Jia-sheng; Deng, Yong-wen; Li, Ming-chu; Chen, Feng-Hua; Wang, Yan-jin; Lu, Ming; Fang, Fang; Wu, Jun; Yang, Zhuan-yi; Zhou, Xang-yang; Wang, Fei; Chen, Cheng

    2007-01-30

    To establish a simplified culture system for the isolation of brain tumor stem cells (BTSCs) from the tumors of human neuroepithelial tissue, to observe the growth and differentiation pattern of BTSCs, and to investigate their expression of the specific markers. Twenty-six patients with brain neuroepithelial tumors underwent tumor resection. Two pieces of tumor tissues were taken from each tumor to be dissociated, triturated into single cells in sterile DMEM-F12 medium, and then filtered. The tumor cells were seeded at a concentration of 200,000 viable cells per mL into serum-free DMEM-F12 medium simply supplemented with B27, human basic fibroblast growth factor (20 microg/L), human epidermal growth factor (20 microg /L), insulin (4 U/L), L-glutamine, penicillin and streptomycin. After the primary brain tumor spheres (BTSs) were generated, they were triturated again and passed in fresh medium. Limiting dilution assay was performed to observe the monoclone formation. 5-bromodeoxyuridine (BrdU) incorporation test was performed to observe the proliferation of the BTS. The BTSCs were cultured in mitogen-free DMEM-F12 medium supplemented with 10% fetal bovine serum to observe their differentiation. Immunocytochemistry was used to examine the expression of CD133 and nestin, specific markers of BTSC, and the rate of CD133 positive cells. Only a minority of subsets of cells from the tumors of neuroepithelial tissue had the capacity to survive, proliferate, and generate free-floating neurosphere-like BTSs in the simplified serum-free medium. These cells attached to the poly-L-lysine coated coverslips in the serum-supplemented medium and differentiated. The BTSCs were CD133 and nestin positive. The rate of CD133 positive cells in the tumor specimens was (21 +/- 6.2)% - (38 +/- 7.0)%. A new simplified culture system for the isolation of BTSCs is established. The tumors of human neuroepithelial tissue contain CD133 and nestin positive tumor stem cells which can be isolated

  5. O-naphthoquinone isolated from Capraria biflora L. induces selective cytotoxicity in tumor cell lines.

    Science.gov (United States)

    de S Wisintainer, G G N; Scola, G; Moura, S; Lemos, T L G; Pessoa, C; de Moraes, M O; Souza, L G S; Roesch-Ely, M; Henriques, J A P

    2015-12-21

    Biflorin is an o-naphthoquinone isolated from the roots of the plant Capraria biflora L. (Scrophulariaceae). In this study, the cytotoxic effects of biflorin were verified, and late apoptosis was detected in various cancer cell lines by in situ analysis. The cytotoxicity was further evaluated exclusively for 48 h of treatment in different tumor and non-tumor cell lines (Hep-2, HeLa, HT-29, A-375, and A-549, and HEK-293, respectively). The results indicated that biflorin induced selective cytotoxicity in tumor cells. HeLa cells were more susceptible to biflorin, followed by HT-29, A-549, A-375, and Hep-2 at all concentrations (range 5-50 μg/mL), and the highest half-maximal inhibitory concentration IC50 (56.01 ± 1.17 μg/mL) was observed in HEK-293 cells. Late apoptotic/necrotic events, observed by in situ immunostaining with Annexin V, varied with each cell line; an increase in late apoptotic events was observed corresponding to the increase in biflorin dosage. Hep-2 cells showed a greater percentage of late apoptotic events among the tumor cell lines when treated with higher concentrations of biflorin (69.63 ± 2.28%). The non-tumor HEK-293 line showed greater resistance to late apoptotic events, as well as a lower level of cytotoxicity (77.69 ± 6.68%) than the tested tumor lines. The data presented indicate that biflorin showed an important, possibly selective, cytotoxicity against tumor cell lines, thereby revealing a promising novel substance with potential anticancer activity for tumor therapy.

  6. Hypoxia targeting therapy with prodrug specifically stabilized and activated in hypoxic tumor cells

    International Nuclear Information System (INIS)

    Kondoh, S.K.; Ueda, T.; Harada, H.; Hiraoka, M.; Akagi, K.

    2003-01-01

    Hypoxia fraction in tumors is associated with increased metastasis and poor survival in patients suffering from malignant tumors such as the head and neck, cervical or breast cancers. Hypoxia can be a direct cause of therapeutic resistance because some drugs and radiation require oxygen to be maximally cytotoxic. Recently we have reported a novel hypoxia targeting prodrug, TOP3, which is a fusion protein, composed of HIV TAT protein transduction domain, a part of HIF1 α ODD domain, and Procaspase-3. TOP3 can be transferred into every cell both in vitro and in vivo but becomes stable only in hypoxic cells, in which TOP3 is activated and induces apoptosis. The application of this fusion protein to a tumor-bearing mouse resulted in significant suppression of the tumor growth and even in reduction of the tumor mass without any obvious side effects. The administrations of TOP3 in combination with a low dose of X-ray showed an additive antitumor effect on pancreatic tumor cells. Furthermore, we show that the rodent model of ascites generated by malignant cells provides an excellent platform of testing hypoxia targeting drugs, since it comprises homogeneous fluid with tumor cells surviving and proliferating under hypoxic condition. TOP3 induced apoptosis of AH130, rat ascites hepatoma cells, in vitro only under hypoxic but not normoxic condition. Intraperitoneal administration of TOP3 prolonged life span of the rats with AH130 derived malignant ascites. Sixty percent of the treated rats were cured of ascites without recurrence for more than six months, in contrast all untreated rats died within 20 days after tumor cell inoculation. These results strongly suggest that TOP3 would provide a new strategy for hypoxia targeting therapy and that the combination of TOP3 with radiotherapy or chemotherapy may provide a new strategy for annihilating malignant tumors

  7. Individual motile CD4+ T cells can participate in efficient multi-killing through conjugation to multiple tumor cells

    Science.gov (United States)

    Liadi, Ivan; Singh, Harjeet; Romain, Gabrielle; Rey-Villamizar, Nicolas; Merouane, Amine; Adolacion, Jay R T.; Kebriaei, Partow; Huls, Helen; Qiu, Peng; Roysam, Badrinath; Cooper, Laurence J.N.; Varadarajan, Navin

    2015-01-01

    T cells genetically modified to express a CD19-specific chimeric antigen receptor (CAR) for the investigational treatment of B-cell malignancies comprise a heterogeneous population, and their ability to persist and participate in serial killing of tumor cells is a predictor of therapeutic success. We implemented Timelapse Imaging Microscopy In Nanowell Grids (TIMING) to provide direct evidence that CD4+CAR+ T cells (CAR4 cells) can engage in multi-killing via simultaneous conjugation to multiple tumor cells. Comparisons of the CAR4 cells and CD8+CAR+ T cells (CAR8 cells) demonstrate that while CAR4 cells can participate in killing and multi-killing, they do so at slower rates, likely due to the lower Granzyme B content. Significantly, in both sets of T cells, a minor sub-population of individual T cells identified by their high motility, demonstrated efficient killing of single tumor cells. By comparing both the multi-killer and single killer CAR+ T cells it appears that the propensity and kinetics of T-cell apoptosis was modulated by the number of functional conjugations. T cells underwent rapid apoptosis, and at higher frequencies, when conjugated to single tumor cells in isolation and this effect was more pronounced on CAR8 cells. Our results suggest that the ability of CAR+ T cells to participate in multi-killing should be evaluated in the context of their ability to resist activation induced cell death (AICD). We anticipate that TIMING may be utilized to rapidly determine the potency of T-cell populations and may facilitate the design and manufacture of next-generation CAR+ T cells with improved efficacy. PMID:25711538

  8. In vivo targeting of dead tumor cells in a murine tumor model using a monoclonal antibody specific for the La autoantigen.

    Science.gov (United States)

    Al-Ejeh, Fares; Darby, Jocelyn M; Pensa, Katherine; Diener, Kerrilyn R; Hayball, John D; Brown, Michael P

    2007-09-15

    To investigate the potential of the La-specific monoclonal antibody (mAb) 3B9 as an in vivo tumor-targeting agent. The murine EL4 lymphoma cell line was used for in vitro studies and the EL4 model in which apoptosis was induced with cyclophosphamide and etoposide was used for in vivo studies. In vitro studies compared 3B9 binding in the EL4 cell with that in its counterpart primary cell type of the thymocyte. For in vivo studies, 3B9 was intrinsically or extrinsically labeled with carbon-14 or 1,4,7,10-tetra-azacylododecane-N,N',N'',N''''-tetraacetic acid-indium-111, respectively, and biodistribution of the radiotracers was investigated in EL4 tumor-bearing mice, which were treated or not with chemotherapy. La-specific 3B9 mAb bound EL4 cells rather than thymocytes, and binding was detergent resistant. 3B9 binding to dead EL4 cells in vitro was specific, rapid, and saturable. Significantly, more 3B9 bound dead EL4 tumor explant cells after host mice were treated with chemotherapy, which suggested that DNA damage induced 3B9 binding. Tumor binding of 3B9 in vivo was antigen specific and increased significantly after chemotherapy. Tumor accumulation of 3B9 peaked at approximately 50% of the injected dose per gram of tumor 72 h after chemotherapy and correlated with increased tumor cell death. Tumor/organ ratios of 3B9 biodistribution, which included the tumor/blood ratio, exceeded unity 48 or more hours after chemotherapy. La-specific mAb selectively targeted dead tumor cells in vivo, and targeting was augmented by cytotoxic chemotherapy. This novel cell death radioligand may be useful both for radioimmunoscintigraphy and radioimmunotherapy.

  9. Selected Alkylating Agents Can Overcome Drug Tolerance of G0-like Tumor Cells and Eradicate BRCA1-Deficient Mammary Tumors in Mice.

    Science.gov (United States)

    Pajic, Marina; Blatter, Sohvi; Guyader, Charlotte; Gonggrijp, Maaike; Kersbergen, Ariena; Küçükosmanoğlu, Aslι; Sol, Wendy; Drost, Rinske; Jonkers, Jos; Borst, Piet; Rottenberg, Sven

    2017-11-15

    Purpose: We aimed to characterize and target drug-tolerant BRCA1-deficient tumor cells that cause residual disease and subsequent tumor relapse. Experimental Design: We studied responses to various mono- and bifunctional alkylating agents in a genetically engineered mouse model for BRCA1/p53 -mutant breast cancer. Because of the large intragenic deletion of the Brca1 gene, no restoration of BRCA1 function is possible, and therefore, no BRCA1-dependent acquired resistance occurs. To characterize the cell-cycle stage from which Brca1 -/- ;p53 -/- mammary tumors arise after cisplatin treatment, we introduced the fluorescent ubiquitination-based cell-cycle indicator (FUCCI) construct into the tumor cells. Results: Despite repeated sensitivity to the MTD of platinum drugs, the Brca1 -mutated mammary tumors are not eradicated, not even by a frequent dosing schedule. We show that relapse comes from single-nucleated cells delaying entry into the S-phase. Such slowly cycling cells, which are present within the drug-naïve tumors, are enriched in tumor remnants. Using the FUCCI construct, we identified nonfluorescent G 0 -like cells as the population most tolerant to platinum drugs. Intriguingly, these cells are more sensitive to the DNA-crosslinking agent nimustine, resulting in an increased number of multinucleated cells that lack clonogenicity. This is consistent with our in vivo finding that the nimustine MTD, among several alkylating agents, is the most effective in eradicating Brca1 -mutated mouse mammary tumors. Conclusions: Our data show that targeting G 0 -like cells is crucial for the eradication of BRCA1/p53-deficient tumor cells. This can be achieved with selected alkylating agents such as nimustine. Clin Cancer Res; 23(22); 7020-33. ©2017 AACR . ©2017 American Association for Cancer Research.

  10. Nanoscale quantification of the biophysical characterization of combretastatin A-4-treated tumor cells using atomic force microscopy.

    Science.gov (United States)

    Li, Yanchun; Chen, Jv; Liu, Yutong; Zhang, Weige; He, Wenhui; Xu, Hanying; Liu, Lianqing; Ma, Enlong

    2017-01-01

    As an inhibitor of microtubule assembly, combretastatin A-4 (CA-4)-induced biological responses in tumor cells have been well known, but the corresponding changes in nano-biophysical properties were not investigated given the lack of an ideal tool. Using AFM technique, we investigated the alteration of nano-biophysical properties when CA-4-treated tumor cells underwent the different biological processes, including cell cycle arrest, apoptosis and autophagy. We found that CA-4-resistant cells were rougher with the presence of characteristic "ridges", indicating that the development of "ridge" structure may be a determinant of the sensitivity of cells to CA-4 compounds. CA-4 induced G2/M arrest and apoptosis in sensitive cells but triggered anti-apoptotic autophagy in resistant cells. CA-4 treatment caused an increase in stiffness in both sensitive and resistant cells. However, these cells exhibited different changes in cell surface roughness. CA-4 decreased Ra and Rq values in sensitive cells but increased these values in resistant cells. The reorganization of F-actin might contribute to the different changes of nano-biophysical properties in CA-4-sensitive and-resistant cells. Our results suggest that cellular nano-biophysical properties, such as "ridges", roughness and stiffness, could be applied as potential biomarkers for evaluating CA-4 compounds, and knowledge regarding how biological alterations cause changes in cellular nano-biophysical properties is helpful to develop a new high-resolution screening tool for anti-tumor agents.

  11. Farnesyl diphosphate synthase is involved in the resistance to zoledronic acid of osteosarcoma cells. : resistance of osteosarcoma to nitrogen bisphosphonates

    OpenAIRE

    Ory , Benjamin; Moriceau , Gatien; Trichet , Valérie; Blanchard , Frédéric; Berreur , Martine; Rédini , Françoise; Rogers , Michael; Heymann , Dominique

    2008-01-01

    International audience; We recently demonstrated original anti-tumor effects of zoledronic acid (Zol) on osteosarcoma cell lines independently of their p53 and Rb status. The present study investigated the potential Zol-resistance acquired by osteosarcoma cells after prolonged treatment. After 12 weeks of culture in the presence of 1 microm Zol, the effects of high doses of Zol (10-100 microm) were compared between the untreated rat (OSRGA, ROS) and human (MG63, SAOS2) osteosarcoma cells and ...

  12. Resistance to Antiangiogenic Therapies by Metabolic Symbiosis in Renal Cell Carcinoma PDX Models and Patients

    Directory of Open Access Journals (Sweden)

    Gabriela Jiménez-Valerio

    2016-05-01

    Full Text Available Antiangiogenic drugs are used clinically for treatment of renal cell carcinoma (RCC as a standard first-line treatment. Nevertheless, these agents primarily serve to stabilize disease, and resistance eventually develops concomitant with progression. Here, we implicate metabolic symbiosis between tumor cells distal and proximal to remaining vessels as a mechanism of resistance to antiangiogenic therapies in patient-derived RCC orthoxenograft (PDX models and in clinical samples. This metabolic patterning is regulated by the mTOR pathway, and its inhibition effectively blocks metabolic symbiosis in PDX models. Clinically, patients treated with antiangiogenics consistently present with histologic signatures of metabolic symbiosis that are exacerbated in resistant tumors. Furthermore, the mTOR pathway is also associated in clinical samples, and its inhibition eliminates symbiotic patterning in patient samples. Overall, these data support a mechanism of resistance to antiangiogenics involving metabolic compartmentalization of tumor cells that can be inhibited by mTOR-targeted drugs.

  13. Quantitative proteomics identifies central players in erlotinib resistance of the non-small cell lung cancer cell line HCC827

    DEFF Research Database (Denmark)

    Jacobsen, Kirstine; Lund, Rikke Raaen; Beck, Hans Christian

    Background: Erlotinib (Tarceva®, Roche) has significantly changed the treatment of non-small cell lung cancer (NSCLC) as 70% of patients show significant tumor regression when treated. However, all patients relapse due to development of acquired resistance, which in 43-50% of cases are caused...... by a secondary mutation (T790M) in EGFR. Importantly, a majority of resistance cases are still unexplained. Our aim is to identify novel resistance mechanisms in erlotinib-resistant subclones of the NSCLC cell line HCC827. Materials & Methods: We established 3 erlotinib-resistant subclones (resistant to 10, 20...... or other EGFR or KRAS mutations, potentiating the identification of novel resistance mechanisms. We identified 2875 cytoplasmic proteins present in all 4 cell lines. Of these 87, 56 and 23 are upregulated >1.5 fold; and 117, 72 and 32 are downregulated >1.5 fold, respectively, in the 3 resistant clones...

  14. General Information about Pancreatic Neuroendocrine Tumors (Islet Cell Tumors)

    Science.gov (United States)

    ... Common Cancer Types Recurrent Cancer Common Cancer Types Bladder Cancer Breast Cancer Colorectal Cancer Kidney (Renal Cell) Cancer ... also called nuclear magnetic resonance imaging (NMRI). Somatostatin receptor scintigraphy : A type of radionuclide scan that may ...

  15. Treatment Option Overview (Pancreatic Neuroendocrine Tumors / Islet Cell Tumors)

    Science.gov (United States)

    ... Common Cancer Types Recurrent Cancer Common Cancer Types Bladder Cancer Breast Cancer Colorectal Cancer Kidney (Renal Cell) Cancer ... also called nuclear magnetic resonance imaging (NMRI). Somatostatin receptor scintigraphy : A type of radionuclide scan that may ...

  16. Genome wide single cell analysis of chemotherapy resistant metastatic cells in a case of gastroesophageal adenocarcinoma

    International Nuclear Information System (INIS)

    Hjortland, Geir Olav; Fodstad, Oystein; Smeland, Sigbjorn; Hovig, Eivind; Meza-Zepeda, Leonardo A; Beiske, Klaus; Ree, Anne H; Tveito, Siri; Hoifodt, Hanne; Bohler, Per J; Hole, Knut H; Myklebost, Ola

    2011-01-01

    Metastatic progression due to development or enrichment of therapy-resistant tumor cells is eventually lethal. Molecular characterization of such chemotherapy resistant tumor cell clones may identify markers responsible for malignant progression and potential targets for new treatment. Here, in a case of stage IV adenocarcinoma of the gastroesophageal junction, we report the successful genome wide analysis using array comparative genomic hybridization (CGH) of DNA from only fourteen tumor cells using a bead-based single cell selection method from a bone metastasis progressing during chemotherapy. In a case of metastatic adenocarcinoma of the gastroesophageal junction, the progression of bone metastasis was observed during a chemotherapy regimen of epirubicin, oxaliplatin and capecitabine, whereas lung-, liver and lymph node metastases as well as the primary tumor were regressing. A bone marrow aspirate sampled at the site of progressing metastasis in the right iliac bone was performed, and single cell molecular analysis using array-CGH of Epithelial Specific Antigen (ESA)-positive metastatic cells, and revealed two distinct regions of amplification, 12p12.1 and 17q12-q21.2 amplicons, containing the KRAS (12p) and ERBB2 (HER2/NEU) (17q) oncogenes. Further intrapatient tumor heterogeneity of these highlighted gene copy number changes was analyzed by fluorescence in situ hybridization (FISH) in all available primary and metastatic tumor biopsies, and ErbB2 protein expression was investigated by immunohistochemistry. ERBB2 was heterogeneously amplified by FISH analysis in the primary tumor, as well as liver and bone metastasis, but homogenously amplified in biopsy specimens from a progressing bone metastasis after three initial cycles of chemotherapy, indicating a possible enrichment of erbB2 positive tumor cells in the progressing bone marrow metastasis during chemotherapy. A similar amplification profile was detected for wild-type KRAS, although more heterogeneously

  17. Neutral evolution of drug resistant colorectal cancer cell populations is independent of their KRAS status.

    Directory of Open Access Journals (Sweden)

    Krastan B Blagoev

    Full Text Available Emergence of tumor resistance to an anti-cancer therapy directed against a putative target raises several questions including: (1 do mutations in the target/pathway confer resistance? (2 Are these mutations pre-existing? (3 What is the relative fitness of cells with/without the mutation? We addressed these questions in patients with metastatic colorectal cancer (mCRC. We conducted an exhaustive review of published data to establish a median doubling time for CRCs and stained a cohort of CRCs to document mitotic indices. We analyzed published data and our own data to calculate rates of growth (g and regression (d, decay of tumors in patients with CRC correlating these results with the detection of circulating MT-KRAS DNA. Additionally we estimated mathematically the caloric burden of such tumors using data on mitotic and apoptotic indices. We conclude outgrowth of cells harboring intrinsic or acquired MT-KRAS cannot explain resistance to anti-EGFR (epidermal growth factor receptor antibodies. Rates of tumor growth with panitumumab are unaffected by presence/absence of MT-KRAS. While MT-KRAS cells may be resistant to anti-EGFR antibodies, WT-KRAS cells also rapidly bypass this blockade suggesting inherent resistance mechanisms are responsible and a neutral evolution model is most appropriate. Using the above clinical data on tumor doubling times and mitotic and apoptotic indices we estimated the caloric intake required to support tumor growth and suggest it may explain in part cancer-associated cachexia.

  18. Cancer Stem Cell Plasticity as Tumor Growth Promoter and Catalyst of Population Collapse

    Directory of Open Access Journals (Sweden)

    Jan Poleszczuk

    2016-01-01

    Full Text Available It is increasingly argued that cancer stem cells are not a cellular phenotype but rather a transient state that cells can acquire, either through intrinsic signaling cascades or in response to environmental cues. While cancer stem cell plasticity is generally associated with increased aggressiveness and treatment resistance, we set out to thoroughly investigate the impact of different rates of plasticity on early and late tumor growth dynamics and the response to therapy. We develop an agent-based model of cancer stem cell driven tumor growth, in which plasticity is defined as a spontaneous transition between stem and nonstem cancer cell states. Simulations of the model show that plasticity can substantially increase tumor growth rate and invasion. At high rates of plasticity, however, the cells get exhausted and the tumor will undergo spontaneous remission in the long term. In a series of in silico trials, we show that such remission can be facilitated through radiotherapy. The presented study suggests that stem cell plasticity has rather complex, nonintuitive implications on tumor growth and treatment response. Further theoretical, experimental, and integrated studies are needed to fully decipher cancer stem cell plasticity and how it can be harnessed for novel therapeutic approaches.

  19. Therapeutic limitations in tumor-specific CD8+ memory T cell engraftment

    International Nuclear Information System (INIS)

    Bathe, Oliver F; Dalyot-Herman, Nava; Malek, Thomas R

    2003-01-01

    Adoptive immunotherapy with cytotoxic T lymphocytes (CTL) represents an alternative approach to treating solid tumors. Ideally, this would confer long-term protection against tumor. We previously demonstrated that in vitro-generated tumor-specific CTL from the ovalbumin (OVA)-specific OT-I T cell receptor transgenic mouse persisted long after adoptive transfer as memory T cells. When recipient mice were challenged with the OVA-expressing E.G7 thymoma, tumor growth was delayed and sometimes prevented. The reasons for therapeutic failures were not clear. OT-I CTL were adoptively transferred to C57BL/6 mice 21 – 28 days prior to tumor challenge. At this time, the donor cells had the phenotypical and functional characteristics of memory CD8+ T cells. Recipients which developed tumor despite adoptive immunotherapy were analyzed to evaluate the reason(s) for therapeutic failure. Dose-response studies demonstrated that the degree of tumor protection was directly proportional to the number of OT-I CTL adoptively transferred. At a low dose of OT-I CTL, therapeutic failure was attributed to insufficient numbers of OT-I T cells that persisted in vivo, rather than mechanisms that actively suppressed or anergized the OT-I T cells. In recipients of high numbers of OT-I CTL, the E.G7 tumor that developed was shown to be resistant to fresh OT-I CTL when examined ex vivo. Furthermore, these same tumor cells no longer secreted a detectable level of OVA. In this case, resistance to immunotherapy was secondary to selection of clones of E.G7 that expressed a lower level of tumor antigen. Memory engraftment with tumor-specific CTL provides long-term protection against tumor. However, there are several limitations to this immunotherapeutic strategy, especially when targeting a single antigen. This study illustrates the importance of administering large numbers of effectors to engraft sufficiently efficacious immunologic memory. It also demonstrates the importance of targeting several

  20. Repeated cisplatin treatment can lead to a multiresistant tumor cell population with stem cell features and sensitivity to 3-bromopyruvate.

    Science.gov (United States)

    Wintzell, My; Löfstedt, Lina; Johansson, Joel; Pedersen, Anne B; Fuxe, Jonas; Shoshan, Maria

    2012-12-01

    Cisplatin is used in treatment of several types of cancer, including epithelial ovarian carcinoma (EOC). In order to mimic clinical treatment and to investigate longterm effects of cisplatin in surviving cancer cells, two EOC cell lines were repeatedly treated with low doses. In the SKOV-3 cell line originating from malignant ascites, but not in A2780 cells from a primary tumor, this led to emergence of a stable population (SKOV-3-R) which in the absence of cisplatin showed increased motility, epithelial-mesenchymal transition (EMT) and expression of cancer stem cell markers CD117, CD44 and ALDH1. Accordingly, the cells formed self-renewing spheres in serum-free stem cell medium. Despite upregulation of mitochondrial mass and cytochrome c, and no upregulation of Bcl-2/Bcl-xL, SKOV-3-R were multiresistant to antineoplastic drugs. Cancer stem cells, or tumor-initiating cells (TICs) are highly chemoresistant and are believed to cause relapse into disseminated and resistant EOC. Our second aim was therefore to target resistance in these TIC-like cells. Resistance could be correlated with upregulation of hexokinase-II and VDAC, which are known to form a survival-promoting mitochondrial complex. The cells were thus sensitive to 3-bromopyruvate, which dissociates hexokinase-II from this complex, and were particularly sensitive to combination treatment with cisplatin at doses down to 0.1 x IC 50. 3-bromopyruvate might thus be of use in targeting the especially aggressive TIC populations.

  1. NKT cells as an ideal anti-tumor immunotherapeutic.

    Science.gov (United States)

    Fujii, Shin-Ichiro; Shimizu, Kanako; Okamoto, Yoshitaka; Kunii, Naoki; Nakayama, Toshinori; Motohashi, Shinichiro; Taniguchi, Masaru

    2013-12-02

    Human natural killer T (NKT) cells are characterized by their expression of an invariant T cell antigen receptor α chain variable region encoded by a Vα24Jα18 rearrangement. These NKT cells recognize α-galactosylceramide (α-GalCer) in conjunction with the MHC class I-like CD1d molecule and bridge the innate and acquired immune systems to mediate efficient and augmented immune responses. A prime example of one such function is adjuvant activity: NKT cells augment anti-tumor responses because they can rapidly produce large amounts of IFN-γ, which acts on NK cells to eliminate MHC negative tumors and also on CD8 cytotoxic T cells to kill MHC positive tumors. Thus, upon administration of α-GalCer-pulsed DCs, both MHC negative and positive tumor cells can be effectively eliminated, resulting in complete tumor eradication without tumor recurrence. Clinical trials have been completed in a cohort of 17 patients with advanced non-small cell lung cancers and 10 cases of head and neck tumors. Sixty percent of advanced lung cancer patients with high IFN-γ production had significantly prolonged median survival times of 29.3 months with only the primary treatment. In the case of head and neck tumors, 10 patients who completed the trial all had stable disease or partial responses 5 weeks after the combination therapy of α-GalCer-DCs and activated NKT cells. We now focus on two potential powerful treatment options for the future. One is to establish artificial adjuvant vector cells containing tumor mRNA and α-GalCer/CD1d. This stimulates host NKT cells followed by DC maturation and NK cell activation but also induces tumor-specific long-term memory CD8 killer T cell responses, suppressing tumor metastasis even 1 year after the initial single injection. The other approach is to establish induced pluripotent stem (iPS) cells that can generate unlimited numbers of NKT cells with adjuvant activity. Such iPS-derived NKT cells produce IFN-γ in vitro and in vivo upon

  2. X-ray sensitivity of human tumor cells in vitro

    International Nuclear Information System (INIS)

    Weichselbaum, R.R.; Nove, J.; Little, J.B.

    1980-01-01

    Clonally-derived cells from ten human malignant tumors considered radiocurable (breast, neuroblastoma, medulloblastoma) or non-radiocurable (osteosarcoma, hypernephroma, glioblastoma, melanoma) were studied in cell culture and their in vitro x-ray survival curve parameters determined (anti n, D 0 ). There were no significant differences among the tumor cell lines suggesting that survival parameters in vitro do not explain differences in clinical radiocurability. Preliminary investigation with density inhibited human tumor cells indicate that such an approach may yield information regarding inherent cellular differences in radiocurability

  3. Reduction of irradiated tumor cells viability under effect of hyperglycemia

    International Nuclear Information System (INIS)

    Meshcherikova, V.V.; Voloshina, E.A.

    1983-01-01

    On Ehrlich carcinoma cells adapted to growth in vivo and in vitro, cellular mechanisms of short-term hyperglycemia effect have been studied. It has been found that SH by itself leads to the loss of viability of a part of cells of ELD solid tumors manifesting during the first 24 hours upon irradiation according to the interphase death type. Tumor cell radiation injuries arising under the effect of irradiation, usually non realized up to the first division, under SH conditions potentiate its injury effect. The phenomena observed explain partially selective injury of tumoral cells in the course of irradiation under SH conditions which testifies to the prospects of its use in clinics

  4. CD4+ and Perivascular Foxp3+ T Cells in Glioma Correlate with Angiogenesis and Tumor Progression

    Directory of Open Access Journals (Sweden)

    Luyan Mu

    2017-11-01

    Full Text Available BackgroundAngiogenesis and immune cell infiltration are key features of gliomas and their manipulation of the microenvironment, but their prognostic significance remains indeterminate. We evaluate the interconnection between tumor-infiltrating lymphocyte (TIL and tumor blood-vasculatures in the context of glioma progression.MethodsPaired tumor tissues of 44 patients from three tumor-recurrent groups: diffuse astrocytomas (DA recurred as DA, DA recurred as glioblastomas (GBM, and GBM recurred as GBM were evaluated by genetic analysis, immunohistochemistry for tumor blood vessel density, TIL subsets, and clinical outcomes. These cells were geographically divided into perivascular and intratumoral TILs. Associations were examined between these TILs, CD34+ tumor blood vessels, and clinical outcomes. To determine key changes in TIL subsets, microarray data of 15-paired tumors from patients who failed antiangiogenic therapy- bevacizumab, and 16-paired tumors from chemo-naïve recurrent GBM were also evaluated and compared.ResultsUpon recurrence in primary gliomas, similar kinetic changes were found between tumor blood vessels and each TIL subset in all groups, but only CD4+ including Foxp3+ TILs, positively correlated with the density of tumor blood vessels. CD4 was the predominant T cell population based on the expression of gene-transcripts in primary GBMs, and increased activated CD4+ T cells were revealed in Bevacizumab-resistant recurrent tumors (not in chemo-naïve recurrent tumors. Among these TILs, 2/3 of them were found in the perivascular niche; Foxp3+ T cells in these niches not only correlated with the tumor vessels but were also an independent predictor of shortened recurrence-free survival (RFS (HR = 4.199, 95% CI 1.522–11.584, p = 0.006.ConclusionThe minimal intratumoral T cell infiltration and low detection of CD8 transcripts expression in primary GBMs can potentially limit antitumor response. CD4+ and perivascular Foxp3

  5. Perspective on Cancer Therapeutics Utilizing Analysis of Circulating Tumor Cells

    Directory of Open Access Journals (Sweden)

    Keun-Yeong Jeong

    2018-04-01

    Full Text Available Various methods are available for cancer screening, and the methods are performed depending on the origin site of cancer. Among these methods, biopsy followed by medical imaging is the most common. After cancer progression is determined, an optimal treatment—such as surgery, chemotherapy, and/or radiation therapy—is selected. A new assay has been developed that detects circulating tumor cells (CTCs. Tracking changes in CTCs may reveal important tumoral sensitivity information or resistance patterns to specific regimens and prompt changes in therapy on a personalized basis. Characterization of CTCs at the DNA, RNA, and protein levels is important for gaining insight for clinical applications. A small number of CTCs can be analyzed to obtain genome information such as the progression of cancer including metastasis, even in a single cluster. Although many clinical studies, particularly CTC enumeration and detection of specific oncogene expression, have increased the success rate of diagnosis and predicting prognosis, there is no consensus regarding the technical approaches and various aspects of the methodology, making it difficult to standardize optimal methods for CTC analysis. However, ongoing technological advances are currently being achieved and large-scale clinical studies are being conducted. Applying CTC analysis in the clinic would be very useful for advancing diagnosis, prognosis prediction, and therapeutics.

  6. Hypoxic cell turnover in different solid tumor lines

    International Nuclear Information System (INIS)

    Ljungkvist, Anna S.E.; Bussink, Johan; Kaanders, Johannes H.A.M.; Rijken, Paulus F.J.W.; Begg, Adrian C.; Raleigh, James A.; Kogel, Albert J. van der

    2005-01-01

    Purpose: Most solid tumors contain hypoxic cells, and the amount of tumor hypoxia has been shown to have a negative impact on the outcome of radiotherapy. The efficacy of combined modality treatments depends both on the sequence and timing of the treatments. Hypoxic cell turnover in tumors may be important for optimal scheduling of combined modality treatments, especially when hypoxic cell targeting is involved. Methods and Materials: Previously we have shown that a double bioreductive hypoxic marker assay could be used to detect changes of tumor hypoxia in relation to the tumor vasculature after carbogen and hydralazine treatments. This assay was used in the current study to establish the turnover rate of hypoxic cells in three different tumor models. The first hypoxic marker, pimonidazole, was administered at variable times before tumor harvest, and the second hypoxic marker, CCI-103F, was injected at a fixed time before harvest. Hypoxic cell turnover was defined as loss of pimonidazole (first marker) relative to CCI-103F (second marker). Results: The half-life of hypoxic cell turnover was 17 h in the murine C38 colon carcinoma line, 23 h and 49 h in the human xenograft lines MEC82 and SCCNij3, respectively. Within 24 h, loss of pimonidazole-stained areas in C38 and MEC82 occurred concurrent with the appearance of pimonidazole positive cell debris in necrotic regions. In C38 and MEC82, most of the hypoxic cells had disappeared after 48 h, whereas in SCCNij3, viable cells that had been labeled with pimonidazole were still observed after 5 days. Conclusions: The present study demonstrates that the double hypoxia marker assay can be used to study changes in both the proportion of hypoxic tumor cells and their lifespan at the same time. The present study shows that large differences in hypoxic cell turnover rates may exist among tumor lines, with half-lives ranging from 17-49 h

  7. Baldness, acne and testicular germ cell tumors

    Science.gov (United States)

    Trabert, Britton; Sigurdson, Alice J.; Sweeney, Anne M.; Amato, Robert J.; Strom, Sara S.; McGlynn, Katherine A.

    2013-01-01

    Androgen levels during critical periods of testicular development may be involved in the etiology of testicular germ cell tumors (TGCT). We evaluated the roles of adolescent and early adult life correlates of androgen exposure and TGCT in a hospital-based case control study. TGCT cases (n=187) and controls (n=148), matched on age, race and state of residence, participated in the study. Unconditional logistic regression was used to estimate associations between TGCT and male pattern baldness, severe acne, markers of puberty onset and body size. Cases were significantly less likely to report hair loss than controls (OR, 0.6; 95% CI, 0.4, 1.0). Amount of hair loss, increasing age at onset and increasing rate of loss were all inversely associated with TGCT (rate of hair loss: p-trend=0.03; age at onset: p-trend=0.03; amount of hair loss: p-trend=0.01). History of severe acne was inversely associated with TGCT (OR, 0.5; 95% CI, 0.3, 0.9) and height was positively associated with TGCT (p-trend=0.02). Increased endogenous androgen levels during puberty and early adulthood may be associated with decreased risk of TGCT. Additional studies of endogenous hormone levels during puberty and early adult life are warranted, especially studies evaluating the role of androgen synthesis, metabolism and uptake. PMID:21128977

  8. Circulating tumor cells in lung cancer.

    Science.gov (United States)

    Young, Rachel; Pailler, Emma; Billiot, Fanny; Drusch, Françoise; Barthelemy, Amélie; Oulhen, Marianne; Besse, Benjamin; Soria, Jean-Charles; Farace, Françoise; Vielh, Philippe

    2012-01-01

    Circulating tumor cells (CTCs) have emerged as potential biomarkers in several cancers such as colon, prostate, and breast carcinomas, with a correlation between CTC number and patient prognosis being established by independent research groups. The detection and enumeration of CTCs, however, is still a developing field, with no universal method of detection suitable for all types of cancer. CTC detection in lung cancer in particular has proven difficult to perform, as CTCs in this type of cancer often present with nonepithelial characteristics. Moreover, as many detection methods rely on the use of epithelial markers to identify CTCs, the loss of these markers during epithelial-to-mesenchymal transition in certain metastatic cancers can render these methods ineffective. The development of personalized medicine has led to an increase in the advancement of molecular characterization of CTCs. The application of techniques such as FISH and RT-PCR to detect EGFR, HER2, and KRAS abnormalities in lung, breast, and colon cancer, for example, could be used to characterize CTCs in real time. The use of CTCs as a 'liquid biopsy' is therefore an exciting possibility providing information on patient prognosis and treatment efficacy. This review summarizes the state of CTC detection today, with particular emphasis on lung cancer, and discusses the future applications of CTCs in helping the clinician to develop new strategies in patient treatment. Copyright © 2012 S. Karger AG, Basel.

  9. Desmoplastic Small Round Cell Tumor of Stomach

    Directory of Open Access Journals (Sweden)

    Ahmed Abu-Zaid

    2013-01-01

    Full Text Available Desmoplastic small round cell tumor (DSRCT is an extremely uncommon, highly aggressive, and malignant mesenchymal neoplasm of undetermined histogenesis. Less than 200 case reports have been documented in literature so far. Herein, we report a 26-year-old otherwise healthy female patient who presented with a 1-month history of epigastric pain. On physical examination, a palpable, slightly mobile, and tender epigastric mass was detected. All laboratory tests were normal. A chest, abdominal, and pelvic contrast-enhanced computed tomography (CT scans showed a 3.8 × 7.2 × 8.7 cm ill-defined mass, involving gastric fundus and extending into gastric cardia and lower gastroesophageal junction. It was associated with multiple enlarged gastrohepatic lymph nodes; the largest measured 1.2 cm. There was no evidence of ascites or retroperitoneal or mesenteric lymphatic metastases. Patient underwent total gastrectomy with D2 lymphadenectomy, splenectomy, and antecolic Roux-en-Y esophagojejunal anastomosis. Histopathological examination revealed coexpression of mesenchymal, epithelial, and neural markers. The characteristic chromosomal translocation (t(11; 22(p13; q12 was demonstrated on fluorescence in situ hybridization (FISH technique. Diagnosis of DSRCT of stomach was confirmed. Patient received no postoperative radiotherapy or chemotherapy. A postoperative 3-month followup failed to show any recurrence. In addition, a literature review on DSRCT is included.

  10. Vulnerability of cultured canine lung tumor cells to NK cell-mediated cytolysis

    International Nuclear Information System (INIS)

    Haley, P.J.; Kohr, J.M.; Kelly, G.; Muggenburg, B.A.; Guilmette, B.A.

    1988-01-01

    Five cell lines, designated as canine lung epithelial cell (CLEP), derived from radiation induced canine lung tumors and canine thyroid adeno-carcinoma (CTAC) cells were compared for their susceptibility to NK cell-mediated cytolysis using peripheral blood lymphocytes from normal, healthy Beagle dogs as effector cells. Effector cells and chromium 51 radiolabeled target cells were incubated for 16 h at ratios of 12.5:1, 25:1, 50:1, and 100:1. Increasing cytolysis was observed for all cell lines as the effector-to-target-cell ratios increased from 12.5:1 to 100:1. The percent cytotoxicity was significantly less for all lung tumor cell lines as compared to CTAC at the 100:1 ratio. One lung tumor cell line, CLEP-9, had 85% of the lytic vulnerability of the CTAC cell line and significantly greater susceptibility to NK cell-mediated lysis than all of the other lung tumor cell lines. Susceptibility to NK cell cytolysis did not correlate with in vivo malignant behavior of the original tumor. These data suggest that cultured canine lung tumor cells are susceptible to NK cell cytolytic activity in vitro and that at least one of these cell lines (CLEP-9) is a candidate for substitution of the standard canine NK cell target, CTAC, in NK cell assays. The use of lung tumor cells in NK cell assays may provide greater insight into the control of lung tumors by immune mechanisms. (author)

  11. Radiologic findings of granulosa cell tumor of the ovary

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Jung Eun; Kim, Kie Hwan; Yoo, Ji Young; Lee, Eun Chun; Lee, Tae Hyun; Chin, Soo Il [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1997-08-01

    To evaluate the radiologic findings of granulosa cell tumor of the ovary. Fourteen cases(fifteen tumors) of pathologically confirmed ovarian granulosa cell tumor were retrospectively analyzed on the basis of CT(n=10), MR imaging(n=4), and ultrasound(n=7) findings. The patients' mean age was 44.3(range, 5-71)years. The mean diameter of the tumors was 12.1(range, 5-26.5)cm. Thirteen cases were unilateral, and one was bilateral. Eleven tumors(ten cases) were mainly solid and eight of these had focal cystic components. Multilocular cysts accounted for three cases, and in two of these, mural nodules were present. One case was a unilocular cyst with no mural nodule. Ten cases were well demarcated. All the solid tumors were enhanced on postcontrast CT and MR imaging. Endometrial thickening was seen in five cases, ascites in six, and peritoneal implants or omental fat infiltration in five. One was associated with lymph node metastasis. All the postmenopausal patients had solid tumors, whereas 66.7%(4 of 6 cases) of young adults and children had cystic tumors. Granulosa cell tumors of the ovary were solid or cystic;the former were more common. There were no characteristic findings which permitted definitive differentiation from other ovarian tumors.

  12. Molecular diagnostics detect radio resistant tumor in cancer cervix

    International Nuclear Information System (INIS)

    Nagarajan, B.

    2004-01-01

    After successful external radiation/intracavitary and interstitial radiation therapy some cancer cervix patients presented with recurrent tumors on 6-12 months follow up period. They had high level of IL-6 on first reporting. This augurs well with the premise that up regulation of IL-6 might be involved in tumor progression

  13. Distributed series resistance effects in solar cells

    DEFF Research Database (Denmark)

    Nielsen, Lars Drud

    1982-01-01

    A mathematical treatment is presented of the effects of one-dimensional distributed series resistance in solar cells. A general perturbation theory is developed, including consistently the induced spatial variation of diode current density and leading to a first-order equivalent lumped resistance...

  14. Exploiting mitochondrial dysfunction for effective elimination of imatinib-resistant leukemic cells.

    Directory of Open Access Journals (Sweden)

    Jérome Kluza

    Full Text Available Challenges today concern chronic myeloid leukemia (CML patients resistant to imatinib. There is growing evidence that imatinib-resistant leukemic cells present abnormal glucose metabolism but the impact on mitochondria has been neglected. Our work aimed to better understand and exploit the metabolic alterations of imatinib-resistant leukemic cells. Imatinib-resistant cells presented high glycolysis as compared to sensitive cells. Consistently, expression of key glycolytic enzymes, at least partly mediated by HIF-1α, was modified in imatinib-resistant cells suggesting that imatinib-resistant cells uncouple glycolytic flux from pyruvate oxidation. Interestingly, mitochondria of imatinib-resistant cells exhibited accumulation of TCA cycle intermediates, increased NADH and low oxygen consumption. These mitochondrial alterations due to the partial failure of ETC were further confirmed in leukemic cells isolated from some imatinib-resistant CML patients. As a consequence, mitochondria generated more ROS than those of imatinib-sensitive cells. This, in turn, resulted in increased death of imatinib-resistant leukemic cells following in vitro or in vivo treatment with the pro-oxidants, PEITC and Trisenox, in a syngeneic mouse tumor model. Conversely, inhibition of glycolysis caused derepression of respiration leading to lower cellular ROS. In conclusion, these findings indicate that imatinib-resistant leukemic cells have an unexpected mitochondrial dysfunction that could be exploited for selective therapeutic intervention.

  15. γ-radiation induces cellular sensitivity and aberrant methylation in human tumor cell lines.

    Science.gov (United States)

    Kumar, Ashok; Rai, Padmalatha S; Upadhya, Raghavendra; Vishwanatha; Prasada, K Shama; Rao, B S Satish; Satyamoorthy, Kapettu

    2011-11-01

    Ionizing radiation induces cellular damage through both direct and indirect mechanisms, which may include effects from epigenetic changes. The purpose of this study was to determine the effect of ionizing radiation on DNA methylation patterns that may be associated with altered gene expression. Sixteen human tumor cell lines originating from various cancers were initially tested for radiation sensitivity by irradiating them with γ-radiation in vitro and subsequently, radiation sensitive and resistant cell lines were treated with different doses of a demethylating agent, 5-Aza-2'-Deoxycytidine (5-aza-dC) and a chromatin modifier, Trichostatin-A (TSA). Survival of these cell lines was measured using 3-(4, 5-Dimethylthiazol- 2-yl)-2, 5-diphenyltetrazolium (MTT) and clonogenic assays. The effect of radiation on global DNA methylation was measured using reverse phase high performance liquid chromatography (RP-HPLC). The transcription response of methylated gene promoters, from cyclin-dependent kinase inhibitor 2A (p16(INK4a)) and ataxia telangiectasia mutated (ATM) genes, to radiation was measured using a luciferase reporter assay. γ-radiation resistant (SiHa and MDAMB453) and sensitive (SaOS2 and WM115) tumor cell lines were examined for the relationship between radiation sensitivity and DNA methylation. Treatment of cells with 5-aza-dC and TSA prior to irradiation enhanced DNA strand breaks, G2/M phase arrest, apoptosis and cell death. Exposure to γ-radiation led to global demethylation in a time-dependent manner in tumor cells in relation to resistance and sensitivity to radiation with concomitant activation of p16(INK4a) and ATM gene promoters. These results provide important information on alterations in DNA methylation as one of the determinants of radiation effects, which may be associated with altered gene expression. Our results may help in delineating the mechanisms of radiation resistance in tumor cells, which can influence diagnosis, prognosis and

  16. N-acetylhexosamine sulfur deriv atives and use of same as cell tumor inhibitors

    OpenAIRE

    Fernández-Mayoralas, Alfonso; Nieto-Sampedro, Manuel; Casas Brugulat, Josefina; García-Álvarez, Isabel; Romero-Ramírez, Lorenzo

    2010-01-01

    [EN] The present invention relates to a series of thioglycosides and to the oxidized sulfoxide and sulfone derivatives thereof, which provide better solubility in aqueous media, and to the use thereof as anti-tumor agents, principally against glioma and pulmonary adenocarcinoma cell lines. The novel thioderivatives are resistant to hydrolysis catalyzed by Nacetylhexosaminadases and reduce the ganglioside content oftmnor cells. The invention likewise relates to a process for obtaining...

  17. Chemo Resistance of Breast Cancer Stem Cells

    National Research Council Canada - National Science Library

    Wicha, Max S

    2006-01-01

    .... Development of this new tool will greatly facilitate future studies. Preliminary results both in xenograft models as well as in neoadjuvant trial are providing strong support for our hypothesis for resistance of cancer cells to chemotherapy...

  18. Role of stem cells in tumor initiation, metastasis formation and their use in cancer therapy

    International Nuclear Information System (INIS)

    Altaner, C.; Altanerova, V.

    2010-01-01

    This review considers recent advances in the stem cell field focusing on the challenges and opportunities for their use in clinical practice. Various kinds of stem cells and their roles in the human organism are in the review described. Attention is given to the role of mesenchymal stem cells as a potential tool in regenerative medicine. The origin and consequences of existence of tumor-initiating cells known as cancer stem cells is discussed also in context of metastasis formation. It seems that tumor-initiating cells might be responsible for resistance to many conventional cancer therapies, which might explain the limitations of these therapeutic modalities. Furthermore, the review focuses to tumor homing property of adult mesenchymal (stromal) stem cells. The feasibility of mesenchymal stem cells isolation from human adipose tissue, their genetic modifications with suicide genes together with ability to find tumor in the organism make them an attractive vehicle for cancer therapy without systemic toxicity. Published achievements from our laboratory in stem cell-based gene cancer therapy are shortly summarized. Generally, it is believed that the stem cell therapies might be ideal future treatment modality for inherited, degenerative diseases and in curing human malignancies as well. (author)

  19. Human tumor cell proliferation evaluated using manganese-enhanced MRI.

    Directory of Open Access Journals (Sweden)

    Rod D Braun

    Full Text Available Tumor cell proliferation can depend on calcium entry across the cell membrane. As a first step toward the development of a non-invasive test of the extent of tumor cell proliferation in vivo, we tested the hypothesis that tumor cell uptake of a calcium surrogate, Mn(2+ [measured with manganese-enhanced MRI (MEMRI], is linked to proliferation rate in vitro.Proliferation rates were determined in vitro in three different human tumor cell lines: C918 and OCM-1 human uveal melanomas and PC-3 prostate carcinoma. Cells growing at different average proliferation rates were exposed to 1 mM MnCl(2 for one hour and then thoroughly washed. MEMRI R(1 values (longitudinal relaxation rates, which have a positive linear relationship with Mn(2+ concentration, were then determined from cell pellets. Cell cycle distributions were determined using propidium iodide staining and flow cytometry. All three lines showed Mn(2+-induced increases in R(1 compared to cells not exposed to Mn(2+. C918 and PC-3 cells each showed a significant, positive correlation between MEMRI R(1 values and proliferation rate (p≤0.005, while OCM-1 cells showed no significant correlation. Preliminary, general modeling of these positive relationships suggested that pellet R(1 for the PC-3 cells, but not for the C918 cells, could be adequately described by simply accounting for changes in the distribution of the cell cycle-dependent subpopulations in the pellet.These data clearly demonstrate the tumor-cell dependent nature of the relationship between proliferation and calcium influx, and underscore the usefulness of MEMRI as a non-invasive method for investigating this link. MEMRI is applicable to study tumors in vivo, and the present results raise the possibility of evaluating proliferation parameters of some tumor types in vivo using MEMRI.

  20. Novel Therapeutic Targets to Inhibit Tumor Microenvironment Induced Castration-Resistant Prostate Cancer

    Science.gov (United States)

    2017-12-01

    AWARD NUMBER: W81XWH-13-1-0163 TITLE: Novel Therapeutic Targets to Inhibit Tumor Microenvironment Induced Castration-resistant Prostate Cancer ...Prostate Cancer 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Feng Yang, Ph.D. 5d. PROJECT NUMBER 5e. TASK NUMBER E-Mail: fyang@bcm.edu...W81XWH-13-1-0163 " Novel Therapeutic Targets to Inhibit Tumor Microenvironment Induced Castration-resistant Prostate Cancer " Introduction AR signaling

  1. Enhanced Radiosensitivity of Tumor Cells Treated with Vanadate in Vitro

    International Nuclear Information System (INIS)

    Lee, Myung Za; Lee, Won Young

    1994-01-01

    Intracellular ions which have a major role in cellular function have been reported to affect repair of radiation damage. Recently it has been reported that ouabain sensitizes A549 tumor cells hut not CCL-120 normal cells to radiation. Ouabain inhibits the Na+-K+-pump rapidly thus it increases intracellular Na concentration. Vanadate which is distributed extensively in almost all living organisms in known to be a Na+-K+-ATPase inhibitors. This study was performed to see any change in radiosensitivity of tumor cell by vanadate and any role of Na+-K+-ATPase in radiosensitization. Experiments have been carried out by pretreatment with vanadate in human cell line(A549, JMG) and mouse cell line(L1210, spleen). For the cell survival MTT assay was performed for A549 and JMG cell and trypan blue dye exclusion test for L120, and spleen cells. Measurements of Na+-K+-ATPase activity in control, vanadate treated cell, radiation treated cell (9 Gy for A549 and JMG, 2 Gy for L1201, spleen), and combined 10-6 M vanadate and radiation treated cells were done. The results were summarized as follows. 1. L1210 cell was most radiosensitive, and spleen cell and JMG cell were intermediate, and A549 cell was least radiosensitive. 2. Minimum or cytotoxicity was seen with vanadate below concentration of 10-6 M. 3. In A549 cells there was a little change in radiosensitivity with treatment of vanadate. However radiation sensitization was shown in low dose level of radiation i. E. 2-Gy. In JMG cells no change in radiosensitivity was noted. Both L1210 and spleen cell had radiosensitization but change was greater in tumor cell. 4. Na+-K+-ATPase activity was inhibited significantly in tumor cell by treatment of vanadate. 5. Radiation itself inhibited Na+-K+-ATPase activity of tumor cell with high Na+- K+-ATPase concention. Increase in radiosensitivity by vanadate was closely associated with original Na+-K+-ATPase contents. From the above results vanadate had little cytotoxicity and it sensitized

  2. uPAR-controlled oncolytic adenoviruses eliminate cancer stem cells in human pancreatic tumors.

    Science.gov (United States)

    Sobrevals, Luciano; Mato-Berciano, Ana; Urtasun, Nerea; Mazo, Adela; Fillat, Cristina

    2014-01-01

    Pancreatic tumors contain cancer stem cells highly resistant to chemotherapy. The identification of therapies that can eliminate this population of cells might provide with more effective treatments. In the current work we evaluated the potential of oncolytic adenoviruses to act against pancreatic cancer stem cells (PCSC). PCSC from two patient-derived xenograft models were isolated from orthotopic pancreatic tumors treated with saline, or with the chemotherapeutic agent gemcitabine. An enrichment in the number of PCSC expressing the cell surface marker CD133 and a marked enhancement on tumorsphere formation was observed in gemcitabine treated tumors. No significant increase in the CD44, CD24, and epithelial-specific antigen (ESA) positive cells was observed. Neoplastic sphere-forming cells were susceptible to adenoviral infection and exposure to oncolytic adenoviruses resulted in elevated cytotoxicity with both Adwt and the tumor specific AduPARE1A adenovirus. In vivo, intravenous administration of a single dose of AduPARE1A in human-derived pancreatic xenografts led to a remarkable anti-tumor effect. In contrast to gemcitabine AduPARE1A treatment did not result in PCSC enrichment. No enrichment on tumorspheres neither on the CD133(+) population was detected. Therefore our data provide evidences of the relevance of uPAR-controlled oncolytic adenoviruses for the elimination of pancreatic cancer stem cells. © 2013.

  3. Cell Competition Drives the Formation of Metastatic Tumors in a Drosophila Model of Epithelial Tumor Formation

    DEFF Research Database (Denmark)

    Eichenlaub, Teresa; Cohen, Stephen M; Herranz, Héctor

    2016-01-01

    . The mechanisms that allow for ongoing cell competition during adult life could, in principle, contribute to tumorigenesis. However, direct evidence supporting this hypothesis has been lacking. Here, we provide evidence that cell competition drives tumor formation in a Drosophila model of epithelial cancer. Cells...

  4. IRF-4 and c-Rel expression in antiviral-resistant adult T-cell leukemia/lymphoma

    OpenAIRE

    Ramos, Juan Carlos; Ruiz, Phillip; Ratner, Lee; Reis, Isildinha M.; Brites, Carlos; Pedroso, Celia; Byrne, Gerald E.; Toomey, Ngoc L.; Andela, Valentine; Harhaj, Edward W.; Lossos, Izidore S.; Harrington, William J.

    2007-01-01

    Adult T-cell leukemia/lymphoma (ATLL) is a generally fatal malignancy. Most ATLL patients fare poorly with conventional chemotherapy; however, antiviral therapy with zidovudine (AZT) and interferon alpha (IFN-α) has produced long-term clinical remissions. We studied primary ATLL tumors and identified molecular features linked to sensitivity and resistance to antiviral therapy. Enhanced expression of the proto-oncogene c-Rel was noted in 9 of 27 tumors. Resistant tumors exhibited c-Rel (6 of 1...

  5. Targeting Tumor Oct4 to Deplete Prostate Tumor and Metastasis Initiating Cells

    Science.gov (United States)

    2017-12-01

    is associated with androgen receptor (AR). We detected Oct4 protein expression in prostate cancer cells as well as in tumor tissue specimens...unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Identification of genes driving prostate carcinogenesis will lead to new cancer treatment. The human...a pseudogene of embryonic Oct4 (POU5F1). A recent study found that tumor Oct4 found in prostate cancer cells is due to the gene expression of POU5F1B

  6.  An Uncommon Presentation of Giant Cell Tumor

    Directory of Open Access Journals (Sweden)

    Gopal Malhotra

    2011-09-01

    Full Text Available  Giant Cell Tumors commonly occur at the ends of long bones. However in rare cases, they can occur in the bones of the hands and feet. Tumors in these locations occur in younger patients; in addition, these tumors are more commonly multifocal and are associated with a higher risk for local recurrence than tumors at the ends of long bones. Since lesions in the small bones may be multifocal, a patient with a giant cell tumor of the small bones should undergo a skeletal survey to exclude similar lesions elsewhere. Primary surgical treatment ranges from curettage or excision with or without bone grafting to amputation. The success of surgical treatment depends on the completeness with which the tumor was removed. We are presenting a case report of a 34 year old female, who presented with a swelling in the right hand, following trauma. X-ray of the hand showed an osteolytic expansile lesion at the base of the 1st metacarpal bone. The lesion was initially curetted and then treated by local resection with bone grafting. Histological examination revealed a typical benign giant cell tumor composed of closely packed stromal cells with a variable admixture of giant cells. Follow up at the end of one year did not reveal any recurrence of the tumor.

  7. Combination of systemic chemotherapy with local stem cell delivered S-TRAIL in resected brain tumors.

    Science.gov (United States)

    Redjal, Navid; Zhu, Yanni; Shah, Khalid

    2015-01-01

    Despite advances in standard therapies, the survival of glioblastoma multiforme (GBM) patients has not improved. Limitations to successful translation of new therapies include poor delivery of systemic therapies and use of simplified preclinical models which fail to reflect the clinical complexity of GBMs. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis specifically in tumor cells and we have tested its efficacy by on-site delivery via engineered stem cells (SC) in mouse models of GBM that mimic the clinical scenario of tumor aggressiveness and resection. However, about half of tumor lines are resistant to TRAIL and overcoming TRAIL-resistance in GBM by combining therapeutic agents that are currently in clinical trials with SC-TRAIL and understanding the molecular dynamics of these combination therapies are critical to the broad use of TRAIL as a therapeutic agent in clinics. In this study, we screened clinically relevant chemotherapeutic agents for their ability to sensitize resistant GBM cell lines to TRAIL induced apoptosis. We show that low dose cisplatin increases surface receptor expression of death receptor 4/5 post G2 cycle arrest and sensitizes GBM cells to TRAIL induced apoptosis. In vivo, using an intracranial resection model of resistant primary human-derived GBM and real-time optical imaging, we show that a low dose of cisplatin in combination with synthetic extracellular matrix encapsulated SC-TRAIL significantly decreases tumor regrowth and increases survival in mice bearing GBM. This study has the potential to help expedite effective translation of local stem cell-based delivery of TRAIL into the clinical setting to target a broad spectrum of GBMs. © 2014 AlphaMed Press.

  8. Vasculature analysis of patient derived tumor xenografts using species-specific PCR assays: evidence of tumor endothelial cells and atypical VEGFA-VEGFR1/2 signalings

    International Nuclear Information System (INIS)

    Bieche, Ivan; Marangoni, Elisabetta; Roman-Roman, Sergio; Decaudin, Didier; Dangles-Marie, Virginie; Vacher, Sophie; Vallerand, David; Richon, Sophie; Hatem, Rana; De Plater, Ludmilla; Dahmani, Ahmed; Némati, Fariba; Angevin, Eric

    2014-01-01

    Tumor endothelial transdifferentiation and VEGFR1/2 expression by cancer cells have been reported in glioblastoma but remain poorly documented for many other cancer types. To characterize vasculature of patient-derived tumor xenografts (PDXs), largely used in preclinical anti-angiogenic assays, we designed here species-specific real-time quantitative RT-PCR assays. Human and mouse PECAM1/CD31, ENG/CD105, FLT1/VEGFR1, KDR/VEGFR2 and VEGFA transcripts were analyzed in a large series of 150 PDXs established from 8 different tumor types (53 colorectal, 14 ovarian, 39 breast and 15 renal cell cancers, 6 small cell and 5 non small cell lung carcinomas, 13 cutaneous melanomas and 5 glioblastomas) and in two bevacizumab-treated non small cell lung carcinomas xenografts. As expected, mouse cell proportion in PDXs -evaluated by quantifying expression of the housekeeping gene TBP- correlated with all mouse endothelial markers and human VEGFA RNA levels. More interestingly, we observed human PECAM1/CD31 and ENG/CD105 expression in all tumor types, with higher rate in glioblastoma and renal cancer xenografts. Human VEGFR expression profile varied widely depending on tumor types with particularly high levels of human FLT1/VEGFR1 transcripts in colon cancers and non small cell lung carcinomas, and upper levels of human KDR/VEGFR2 transcripts in non small cell lung carcinomas. Bevacizumab treatment induced significant low expression of mouse Pecam1/Cd31, Eng/Cd105, Flt1/Vegfr1 and Kdr/Vefr2 while the human PECAM1/CD31 and VEGFA were upregulated. Taken together, our results strongly suggest existence of human tumor endothelial cells in all tumor types tested and of both stromal and tumoral autocrine VEGFA-VEGFR1/2 signalings. These findings should be considered when evaluating molecular mechanisms of preclinical response and resistance to tumor anti-angiogenic strategies

  9. Overexpression of the duffy antigen receptor for chemokines (DARC) by NSCLC tumor cells results in increased tumor necrosis

    International Nuclear Information System (INIS)

    Addison, Christina L; Belperio, John A; Burdick, Marie D; Strieter, Robert M

    2004-01-01

    The Duffy antigen receptor for chemokines (DARC) is known to be a promiscuous chemokine receptor that binds a variety of CXC and CC chemokines in the absence of any detectable signal transduction events. Within the CXC group of chemokines, DARC binds the angiogenic CXC chemokines including IL-8 (CXCL8), GROα (CXCL1) and ENA-78 (CXCL5), all of which have previously been shown to be important in non-small cell lung carcinoma (NSCLC) tumor growth. We hypothesized that overexpression of DARC by a NSCLC tumor cell line would result in the binding of the angiogenic ELR+ CXC chemokines by the tumor cells themselves, and thus interfere with the stimulation of endothelial cells and induction of angiogenesis by the tumor cell-derived angiogenic chemokines. NSCLC tumor cells that constitutively expressed DARC were generated and their growth characteristics were compared to control transfected cells in vitro and in vivo in SCID animals. We found that tumors derived from DARC-expressing cells were significantly larger in size than tumors derived from control-transfected cells. However, upon histological examination we found that DARC-expressing tumors had significantly more necrosis and decreased tumor cellularity, as compared to control tumors. Expression of DARC by NSCLC cells was also associated with a decrease in tumor-associated vasculature and a reduction in metastatic potential. The expression of DARC in the context of NSCLC tumors may act as a chemokine decoy receptor and interferes with normal tumor growth and chemokine-induced tumor neovascularization

  10. Establishment and Characterization of a Tumor Stem Cell-Based Glioblastoma Invasion Model.

    Directory of Open Access Journals (Sweden)

    Stine Skov Jensen

    Full Text Available Glioblastoma is the most frequent and malignant brain tumor. Recurrence is inevitable and most likely connected to tumor invasion and presence of therapy resistant stem-like tumor cells. The aim was therefore to establish and characterize a three-dimensional in vivo-like in vitro model taking invasion and tumor stemness into account.Glioblastoma stem cell-like containing spheroid (GSS cultures derived from three different patients were established and characterized. The spheroids were implanted in vitro into rat brain slice cultures grown in stem cell medium and in vivo into brains of immuno-compromised mice. Invasion was followed in the slice cultures by confocal time-lapse microscopy. Using immunohistochemistry, we compared tumor cell invasion as well as expression of proliferation and stem cell markers between the models.We observed a pronounced invasion into brain slice cultures both by confocal time-lapse microscopy and immunohistochemistry. This invasion closely resembled the invasion in vivo. The Ki-67 proliferation indexes in spheroids implanted into brain slices were lower than in free-floating spheroids. The expression of stem cell markers varied between free-floating spheroids, spheroids implanted into brain slices and tumors in vivo.The established invasion model kept in stem cell medium closely mimics tumor cell invasion into the brain in vivo preserving also to some extent the expression of stem cell markers. The model is feasible and robust and we suggest the model as an in vivo-like model with a great potential in glioma studies and drug discovery.

  11. Apoptosis and tumor cell death in response to HAMLET (human alpha-lactalbumin made lethal to tumor cells).

    Science.gov (United States)

    Hallgren, Oskar; Aits, Sonja; Brest, Patrick; Gustafsson, Lotta; Mossberg, Ann-Kristin; Wullt, Björn; Svanborg, Catharina

    2008-01-01

    HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a molecular complex derived from human milk that kills tumor cells by a process resembling programmed cell death. The complex consists of partially unfolded alpha-lactalbumin and oleic acid, and both the protein and the fatty acid are required for cell death. HAMLET has broad antitumor activity in vitro, and its therapeutic effect has been confirmed in vivo in a human glioblastoma rat xenograft model, in patients with skin papillomas and in patients with bladder cancer. The mechanisms of tumor cell death remain unclear, however. Immediately after the encounter with tumor cells, HAMLET invades the cells and causes mitochondrial membrane depolarization, cytochrome c release, phosphatidyl serine exposure, and a low caspase response. A fraction of the cells undergoes morphological changes characteristic of apoptosis, but caspase inhibition does not rescue the cells and Bcl-2 overexpression or altered p53 status does not influence the sensitivity of tumor cells to HAMLET. HAMLET also creates a state of unfolded protein overload and activates 20S proteasomes, which contributes to cell death. In parallel, HAMLET translocates to tumor cell nuclei, where high-affinity interactions with histones cause chromatin disruption, loss of transcription, and nuclear condensation. The dying cells also show morphological changes compatible with macroautophagy, and recent studies indicate that macroautophagy is involved in the cell death response to HAMLET. The results suggest that HAMLET, like a hydra with many heads, may interact with several crucial cellular organelles, thereby activating several forms of cell death, in parallel. This complexity might underlie the rapid death response of tumor cells and the broad antitumor activity of HAMLET.

  12. Role of tumor necrosis factor in macrophage leishmanicidal activity in vitro and resistance to cutaneous leishmaniasis in vivo.

    Science.gov (United States)

    Theodos, C M; Povinelli, L; Molina, R; Sherry, B; Titus, R G

    1991-01-01

    Recombinant human tumor necrosis factor (TNF) and purified murine TNF were both able to activate macrophages to destroy intracellular Leishmania major in vitro. In addition, parasitizing macrophages with L. major markedly increased the ability of the cells to produce TNF. Finally, when mice were vaccinated with an avirulent form of L. major, the animals produced large amounts of TNF but no gamma interferon in response to infection with virulent L. major. Treating these mice with a neutralizing anti-TNF antibody led to partial but not complete inhibition of the resistant state, which suggests that factors other than TNF and gamma interferon contribute to resistance to L. major. PMID:1906844

  13. Effects of X-irradiation on artificial blood vessel wall degradation by invasive tumor cells

    International Nuclear Information System (INIS)

    Heisel, M.A.; Laug, W.E.; Stowe, S.M.; Jones, P.A.

    1984-01-01

    Artificial vessel wall cultures, constructed by growing arterial endothelial cells on preformed layers of rat smooth muscle cells, were used to evaluate the effects of X-irradiation on tumor cell-induced tissue degradation. Bovine endothelial cells had radiation sensitivities similar to those of rat smooth muscle cells. Preirradiation of smooth muscle cells, before the addition of human fibrosarcoma (HT 1080) cells, did not increase the rate of degradation and destruction by the invasive cells. However, the degradation rate was decreased if the cultures were irradiated after the addition of HT 1080 cells. The presence of bovine endothelial cells markedly inhibited the destructive abilities of fibrosarcoma cells, but preirradiation of artificial vessel walls substantially decreased their capabilities to resist HT 1080-induced lysis. These findings suggest that the abilities of blood vessels to limit extravasation may be compromised by ionizing radiation

  14. Exosome-Based Cell-Cell Communication in the Tumor Microenvironment

    Directory of Open Access Journals (Sweden)

    Joana Maia

    2018-02-01

    Full Text Available Tumors are not isolated entities, but complex systemic networks involving cell-cell communication between transformed and non-transformed cells. The milieu created by tumor-associated cells may either support or halt tumor progression. In addition to cell-cell contact, cells communicate through secreted factors via a highly complex system involving characteristics such as ligand concentration, receptor expression and integration of diverse signaling pathways. Of these, extracellular vesicles, such as exosomes, are emerging as novel cell-cell communication mediators in physiological and pathological scenarios. Exosomes, membrane vesicles of endocytic origin released by all cells (both healthy and diseased, ranging in size from 30 to 150 nm, transport all the main biomolecules, including lipids, proteins, DNAs, messenger RNAs and microRNA, and perform intercellular transfer of components, locally and systemically. By acting not only in tumor cells, but also in tum