Project description:p53 mutation is common and highly related to radiotherapy resistance in rectal cancer. APR-246, as a small molecule, can restore the tumor-suppressor function to mutant p53. There is no study on combining APR-246 with radiation in rectal cancer; therefore, we examined whether APR-246 sensitized colorectal cancer cells with different p53 status to radiation. The combination treatment had synergistic effects on HCT116p53-R248W/-(p53Mut) cells, followed by HCT116p53+/+(p53WT) cells, and exhibited an additive effect on HCT116p53-/-(p53Null) cells through inhibiting proliferation, enhancing reactive oxygen species, and apoptosis. The results were confirmed in zebrafish xenografts. Comparison of the transcriptome in colorectal cancer cells with different p53 status 72hrs post-treatment with APR-246, irradiation, or the combination of APR-246 with irradiation was carried out. p53Mut and p53WT cells shared more activated pathways and differentially expressed genes following the combination treatment, compared to p53Null cells, although the combination treatment regulated individual pathways in the different cell lines. APR-246 mediated radio-sensitization effects through p53-dependent and -independent ways.
Project description:We sequenced the genomes of 32 isofemale fly lines from two divergent microclimates at 'Evolution Canyon' in Israel (16 fly lines from each microclimate).
Project description:Proteins from Mortierella elongata/Candidatus Glomeribacter sp. symbiotic system were extracted, trypsine digested and identified with LC-MS/MS analysis.
Project description:Identification of ovarian cancer (OvCa) patient subpopulations with increased sensitivity to targeted therapies could offer significant clinical benefit. We report that 22 % of the high grade OvCa tumors at diagnosis express CIP2A oncoprotein at low levels. Further, regardless of their significantly lower likelihood of disease relapse after standard chemotherapy, a portion of relapsed tumors retain their CIP2A-deficient phenotype. Through a screen for therapeutics that would preferentially kill CIP2A-deficient OvCa cells, we identified reactive oxygen species inducer APR-246, tested previously in OvCa clinical trials. Consistent with CIP2A-deficient OvCa subtype in humans, CIP2A is dispensable for development of MISIIR-Tag-driven mouse OvCa tumors. Nevertheless, CIP2A null OvCa tumor cells from MISIIR-Tag mice displayed APR-246 hypersensitivity both in vitro and in vivo. Mechanistically, the lack of CIP2A expression hypersensitizes the OvCa cells to APR-246 by inhibition of NF-kB activity. Accordingly, combination of APR-246 and NF-kB inhibitor compounds strongly synergized in killing of CIP2A positive OvCa cells. Collectively, the results warrant consideration of clinical testing of APR-246 for CIP2A-deficient OvCa tumor subtype patients. Results also reveal CIP2A as a candidate APR-246 combination therapy target for ovarian cancer.
Project description:Though p53 mutations are rare in Ewing sarcoma, there is a strong indication that p53-mutant tumors form a particularly bad prognosis group. As such, novel treatment strategies are warranted that would specifically target and eradicate tumor cells containing mutant-p53 in this subset of ES patients. PRIMA-1Met/APR-246 is a small organic molecule which has been shown to restore tumor suppressor function primarily to mutant p53 and to also induce cell death in various cancer cell types. We analyzed the apoptosis inducibility on Ewing sarcoma cells harbouring different p53 mutations upon exposure to APR-246. Gene expression profiles of three STA-ET-7 cell lines established from the same patient at different stages of the disease was assessed by microarray analysis as these cell lines responded variably to APR-246.
Project description:The Candidatus phylum Omnitrophica (candidate division OP3) occurs ubiquitous in anaerobic habitats, but is currently characterized only by draft genomes from metagenomes and single cells. We had visualized cells of the phylotype OP3 LiM in methanogenic cultures on limonene as small epibiontic cells. In this study, we enriched OP3 cells by double density centrifugation and obtained the first closed genome of an apparently clonal OP3 cell population applying metagenomics and PCR for gap closure. Filaments of acetoclastic Methanosaeta, the largest morphotype in limonene enrichment cultures, contained empty cells, dead cells and cells devoid of rRNA or both rRNA and DNA according to TEM, thin-section TEM, SEM, CARD-FISH and Live/Dead images. OP3 LiM cells were ultramicrobacteria (200-300 nm in diameter) and showed two physiological stages in CARD-FISH fluorescence signals: strong signals indicated many rRNA molecules and an active metabolism of OP3 LiM cells attached to Bacteria and to Archaea, whereas free-living OP3 cells had weak signals. Metaproteomics revealed that OP3 LiM lives with highly expressed secreted proteins involved in depolymerization and uptake of macromolecules, an active glycolysis and energy conservation by the utilization of pyruvate via a pyruvate:ferredoxin oxidoreductase and an RNF complex (Ferredoxin:NAD oxidoreductase). Besides sugar fermentation, a nucleotidyl transferase may contribute to energy conservation by phosphorolysis, the phosphate-dependent depolymerization of nucleic acids. Thin section TEM showed distinctive structures of predation that had been previously observed for “Velamenicoccus”. Our study demonstrated a predatory metabolism for OP3 LiM cells and we propose as name for OP3 LiM Candidatus Velamenicoccus archaeovorus gen. nov., sp. nov..