280 TP53 domains' mutations alter glycolysis in epithelial ovarian carcinoma: ex-vivo and in vitro study. (18th September 2019) - Atallah, D
Abstract : Objectives: To investigate the effect of TP53 different domain mutations on its transcriptional activity, its ability to induce apoptosis and to regulate glucose consumption and lactate production in epithelial ovarian cancer Methods: 30 ovarian cancer biopsies were characterized. Viability and Annexin V tests were performed to study the ability of mutant p53 to induce apoptosis. The expression of the glycolytic enzymes regulated by p53 was quantified by qPCR. SK-OV-3 cell line was transfected by different p53 mutated plasmids, and the same experiments performed on the biopsies were done on transfected cells. Results: 17 out of 22 ovarian cancer cases were characterized as High-Grade Serous Carcinoma. Out of these 17, mutations were detected in 9 of the cases. 8 patients showed mutations affecting the apoptosis domain of the gene (exons 2, 3 and 4). The immunohistochemistry and qPCR showed an approximately 2 folds increase in p53 expression between wild type and mutated cases. The expression of p21 and MDM2 decreased only in DNA binding domain mutated cases and transfected cells, which indicates a decreased transcriptional activity with this type of mutation. The highest increase in apoptosis induction was clear in Sk-Ov-3 cells transfected with WT p53, and p53 proline rich domain mutations decreased the protein's apoptotic function. Glucose consumption and lactate production increased by mutated cells compared to wild type. Conclusions: Mutant p53 is overexpressed in ovarian cancer cells. DNA binding domain mutations modify the protein's transcriptional activity, whereas proline rich domain mutations decrease the protein's apoptotic activity. Glycolysis is affected differently in both types.