miR-200c regulates malignant biological behaviors of triple negative breast cancer MDA-MB-231 cells via targeting cell energy metabolism and multiple signaling pathways / 中国肿瘤生物治疗杂志

ABSTRACT

@#Objective: To investigate the effects of miR-200c on the proliferation, apoptosis and migration of triple negative breast cancer cell (TNBC) MDA-MB-231 and its metabolism-related molecular mechanism. Methods: miR-200c-231 (MDA-MB-231 overexpressing miR-200c) cells, miR-NC-231 (MDA-MB-231 transfected with miRNA-negative control) and the corresponding transplanted tumor models in nude mice were used as the study subjects. qPCR was used to detect the content of miR-200c and other related genes in cells and transplanted tumor tissues. The number of Ki67 positive cells in tumor tissue was analyzed by immunohistochemistry. The migration and apoptosis of cells were examined by Transwell chamber method and Flow cytometry, respectively. The expressions of proteins associated with proliferation, migration, and metabolism related signaling pathways in cells and tissues were confirmed by Western blotting. The changes of oxygen consumption rate (OCR), extracellular acidification rate (ECAR) and metabolic phenotype were detected by Seahorse energy metabolism detector. UPLC/LTQ-Orbitrap-MStechniquewasusedtoprofilethedifference of metabolites in cells. Results: The content of miR-200c in miR-200c-231cellswassignificantlyhigherthanthatinmiR-NC-231cells.Themass ofmiR-200c-231transplantedtumornotablydecreased,andthenumberofKi67positivecellsintumortissuesalsodecreasedsignificantly. The migration ability of miR-200c-231 cells decreased and the apoptosis rate increased (all P<0.01), accompanied with declined expressionsofZEB1/2,Vimentin,cyclinD1andincreasedexpressionofcleavedPARP(P<0.05orP<0.01),aswellasdecreasedphosphorylation leverofSTAT1/3andNF-κBbutincresedphosphorylationleverofCAMP(allP<0.05).OverexpressionofmiR-200cinMDA-MB-231cells increasedOCRandthecontentof10antitumor metabolites, but decreased ECAR and tryptophan 2,3-plus dioxidase (TDO2) expression (P<0.05 or P<0.01). Conclusion: miR-200c targeting TDO2 elevates the level of intracellular anticancer metabolites in TNBC MDAMB-231 cells, promotes the transformation from glycolysis to aerobic respiration phenotype, and inactivates STAT3 and NF-κB pathyway but activates cAMPpathway TNBC MDA-MB-231 cells, thus affects the malignant biological behaviors of MDA-MB-231 cells.