Abstract
Background
Accumulating evidences reveal that aberrant microRNAs (miRNAs) expression can affect the development of chemotherapy drug resistance by modulating the expression of relevant target proteins. Emerging evidences have demonstrated that miR-133a participates in tumorigenesis of various cancers. However, whether miR-133a is associated with cisplatin resistance in ovarian cancer remains unclear.
Objective
To investigate the role of miR-133a in the development of cisplatin resistance in ovarian cancer.
Methods
MiR-133a expression in cisplatin-resistant ovarian cancer cell lines was assessed by reverse-transcription quantitative PCR (RT-qPCR). Cell counting kit-8 (CCK-8) assay was used to evaluate cell viability of tumor cells treated with cisplatin in the presence or absence of miR-133a. Luciferase reporter assay was used to analyze binding of miR-133a with 3’ untranslated regions (3’UTR) of YES proto-oncogene 1 (YES1). The YES1 expression level was analyzed using the dataset from the international cancer genome consortiu (ICGC) and assessed by RT-qPCR and western blotting in vitro. The roles and mechanisms of YES1 on cell functions were further probed via gain- and loss-of-function analysis.
Results
The expression of miR-133a was significantly decreased in cisplatin resistant ovarian cancer cell lines (A2780-DDP and SKOV3-DDP), and the overexpression of miR-133a mimic reduced cisplatin resistance in A2780-DDP and SKOV3-DDP cells and the treatment of miR-133a inhibitor increased cisplatin sensitive in normal A2780 and SKOV3 cells. MiR-133a binds 3’UTR of YES1 and down-regulates its expression. Bioinformatics analysis revealed that YES1 expression was upregulated in recurrent cisplatin resistance ovarian cancer tissue and in vitro experiments also verified its upregulating in cisplatin resistance cell lines. Furthermore, we discovered that miR-133a down-regulated the expression of YES1 and thus inhibited the cell autophagy to reduce cisplatin resistance. Yes1 knockdown significantly suppressed the cisplatin resistance of ovarian cancer cells through inhibiting autophagy in vitro. Xenograft tumor implantation further demonstrated that Yes1 overexpression promoted ovarian tumor development and cisplatin resistance.
Conclusion
Our results suggest that miR-133a/YES1 axis plays a critical role in cisplatin resistance in human ovarian cancer by regulating cell autophagy, which might serve as a promising therapeutic target for ovarian cancer chemotherapy treatment in the future.
Global Analysis of DNA Methylation by Methyl-Capture Sequencing Reveals Epigenetic Control of Cisplatin Resistance in Ovarian Cancer Cell
