Al-Momani, E.; Malik, N.; Machulla, H.J.; Reske, S.N.; Solbach, C.
An efficient radiosynthesis of [ 18 F]FEt-Tyr-urea-Glu ([ 18 F]FEtTUG) as a new ligand for prostate specific membrane antigen (PSMA) was developed by use of [ 18 F]fluoroethyltosylate as labeling precursor. The corresponding fluoroethyl-tyrosine-urea-glutamate peptide was prepared as reference standard for HPLC control and identified and characterized by standard procedures (MS, NMR). The labeling conditions were optimized with respect to reaction time, reaction temperature, base and solvent. The maximal radiochemical yield of [ 18 F]FEtTUG (77 ± 0.8 %) was obtained within a reaction time of 15 min at a reaction temperature of 80 deg C using 10 M NaOH (18 equiv. related to precursor) in 80 % aqueous acetonitrile. The total preparation time including radiosynthesis, hydrolysis, HPLC purification and formulation was 70 min (EOB). The radiochemical purity was ≥98 %. (author)
Tulstrup, Morten; Larsen, Hanne Bækgaard; Castor, Anders
compared to younger children in trials with different toxicity profiles. PROCEDURE: Age-dependent participation rates in three consecutive, randomized childhood leukemia trials conducted by the Nordic Society of Paediatric Haematology and Oncology were evaluated. The ALL2000 dexamethasone/vincristine (Dx...... prospectively registered by the treating physicians. RESULTS: Parents of young children favored treatment intensifications (Dx/VCR: 12% refusal; 6MP: 14%; ASP: 21%), whereas parents of adolescents favored treatment reductions (Dx/VCR: 52% refusal; 6MP: 30%; ASP: 8%). Adolescents were more likely to refuse...... intensification trials than young children (adjusted ORs 6.3; P treatment (adjusted OR for median consolidation length 0.15; P = 0...
Fu, Zhi-guang; Wang, Li; Cui, Hong-yong; Peng, Jian-long; Wang, Shi-jie; Geng, Jie-jie; Liu, Ji-de; Feng, Fei; Song, Fei; Li, Ling; Zhu, Ping; Jiang, Jian-li; Chen, Zhi-nan
CD147, a type I transmembrane glycoprotein, is highly expressed in various cancer types and plays important roles in tumor progression, especially by promoting the motility and invasion of hepatocellular carcinoma (HCC) cells. These crucial roles make CD147 an attractive target for therapeutic intervention in HCC, but no small-molecule inhibitors of CD147 have been developed to date. To identify a candidate inhibitor, we used a pharmacophore model derived from the structure of CD147 to virtually screen over 300,000 compounds. The 100 highest-ranked compounds were subjected to biological assays, and the most potent one, dubbed AC-73 (ID number: AN-465/42834501), was studied further. We confirmed that AC-73 targeted CD147 and further demonstrated it can specifically disrupt CD147 dimerization. Moreover, molecular docking and mutagenesis experiments showed that the possible binding sites of AC-73 on CD147 included Glu64 and Glu73 in the N-terminal IgC2 domain, which two residues are located in the dimer interface of CD147. Functional assays revealed that AC-73 inhibited the motility and invasion of typical HCC cells, but not HCC cells that lacked the CD147 gene, demonstrating on-target action. Further, AC-73 reduced HCC metastasis by suppressing matrix metalloproteinase (MMP)-2 via down-regulation of the CD147/ERK1/2/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Finally, AC-73 attenuated progression in an orthotopic nude mouse model of liver metastasis, suggesting that AC-73 or its derivatives have potential for use in HCC intervention. We conclude that the novel small-molecule inhibitor AC-73 inhibits HCC mobility and invasion, probably by disrupting CD147 dimerization and thereby mainly suppressing the CD147/ERK1/2/STAT3/MMP-2 pathways, which are crucial for cancer progression.
Sharma, Mrinal; Prabha, C Ratna
Ubiquitin, a small eukaryotic protein serving as a post-translational modification on many important proteins, plays central role in cellular homeostasis and cell cycle regulation. Ubiquitin features two beta-bulges, the second beta-bulge, located at the C-terminal region of the protein along with type II turn, holds 3 residues Glu64(1), Ser65(2) and Gln2(X). Percent frequency of occurrence of such a sequence in parallel beta-bulge is very low. However, the sequence and structure have been conserved in ubiquitin through out the evolution. Present study involves replacement of residues in unusual beta-bulge of ubiquitin by introducing mutations in combination through site directed mutagenesis, generating double and triple mutants and their functional characterization. Mutant ubiquitins cloned in yeast expression vector YEp96 tested for growth profile, viability assay and heat stress complementation study have revealed significant decrease in growth rate, loss of viability and non-complementation of heat sensitive phenotype with UbE64G-S65D and UbQ2N-E64G-S65D mutations. However, UbQ2N-S65D did not show any negative effects in the above assays. Present results show that, replacement of residues in beta-bulge of ubiquitin exerts severe effects on growth and viability in Saccharomyces cerevisiae due to functional failure of the mutant ubiquitins UbE64G-S65D and UbQ2N-E64G-S65D.
Full Text Available Diversity of colors in flowers and fruits is largely due to anthocyanin pigments. The flavonoid/anthocyanin pathway has been most extensively studied. Dihydroflavonol 4-reductase (DFR is a vibrant enzyme of the flavonoid pathway which displays major impact on the formation of anthocyanins, flavan 3-ols and flavonols. The substrate specificity of the DFR was found to play a crucial role in determination of type of anthocyanidins. Altering the flavonoid/ anthocyanin pathway through genetic engineering to develop color of our own choice is an exciting subject of future research. In the present study, comparison among four DFR genes (Gossypium hirsutum, Iris × hollandica, Ang. DFRI and DFRII, sequence alignment for homology as well as protein modeling and docking is demonstrated. Estimation of catalytic sites, prediction of substrate preference and protein docking were the key features of this article. For specific substrate uptake, a proline rich region and positions 12 plus 26 along with other positions emphasizing the 26-amino acid residue region (132-157 was tested. Results showed that proline rich region position 12, 26 and 132-157 plays an important role in selective attachment of DFRs with respective substrates. Further, ‘Expasy ProtParam tool’ results showed that Iris × hollandica DFR amino acids (Asn 9: Asp 23 favorable for reducing DHQ and DHM thus accumulating delphinidin, while Gossypium hirsutum DFR has (Asn 13: Asp 21 hypothesized to consume DHK. Protein docking data showed that amino acid residues in above mentioned positions were just involved in attachment of DFR with substrate and had no role in specific substrate uptake.Advanced bioinformatics analysis has revealed that all above mentioned positions have role in substrate attachment. For substrate specificity, other residues region is involved. It will help in color manipulations in different plant species.