Abstract
The therapeutic outcomes of ovarian cancer (OVCA) patients are majorly limited by the development of acquired chemo/radioresistance and the lack of targeted therapies. Accumulating studies demonstrate that microRNAs are involved in tumorigenesis and radioresistance. This study aims to illustrate the role of miR-588 in the radioresistance of OVCA cells. The levels of miR-588 and mRNAs were detected by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR). OVCA cell viability, proliferative, migratory and invasive capacities were evaluated by the cell counting kit-8 (CCK-8) assay, colony formation assay, wound healing assay and transwell assay, respectively. The luciferase activities of plasmids containing wild -type and mutant serine/arginine-rich splicing factor 6 (SRSF6) 3'-untranslated region in miR-588 silenced OVCA cells were detected by a luciferase reporter assay. We found that miR-588 was overexpressed in OVCA tissues and cells. Knockdown of miR-588 exerted an inhibitory effect on the proliferation, migration and invasion and strengthened the radiosensitivity of OVCA cells, whereas overexpression of miR-588 increased the radioresistance of OVCA cells. SRSF6 was verified to be targeted by miR-588 in OVCA cells. In addition, the expression level of miR-588 was negatively correlated with that of SRSF6 in OVCA clinical samples. Rescue assays indicated that SRSF6 knockdown reversed the effect of miR-588 inhibition of OVCA cells under radiation. Overall, miR-588 acts as an oncogene in OVCA and increases the radioresistance of OVCA cells by targeting SRSF6.