Figure 1.

Twist expression regulates DNA damage response (DDR) proteins, PARP1 and XRCC1 during the development of cisplatin resistance in ovarian cancer (OC) cells. (A) Schematic repre-setantion of how four intermediate sublines were generated between parental and CisR OC cells. (B) Western blot analysis of Twist and DDR proteins, PARP1 and XRCC1 in each subline of OV90-CisR and SKOV3-CisR. (C) Clonogenic cell growth assay for cisplatin, olaparib and niraparib with the doses of 20 µM, each respectively, for 72 h of treatment followed by 72 h recovery in each subline of OV90-CisR and SKOV3-CisR. (D) Measurement of 50% inhibitory concentration (IC₅₀) values of cisplatin, olaparib and niraparib on CisR OC cells compared with their respective parental cells. P: parental cell; CisR: cisplatin-resistant cells; G: sublines of each respective generation. Values were represented as mean ± SD. * p < 0.05, ** p < 0.01, compared with their respective parental cells.