Fig. 2

RAD51 overexpressing oral cancer cells survived better with less apoptotic cells after irradiation and cisplatin. (A) Colony formation assay in human oral cavity squamous cell carcinoma cell line, OECM1 EV (control) and OECM1 RAD51 OE (overexpression) cells after different doses of irradiation, and OECM1 RAD51 OE cells had more colonies after irradiation, (B) The quantification of colony formation showed that OECM1 RAD51 OE cells had better survival after different doses of irradiation than OECM1 EV cells, (C) XTT assay in OECM1 EV and OECM1 RAD51 OE cells at 72 h after irradiation showed that OECM1 RAD51 OE cells had higher cell viability after irradiation, (D) OECM1 EV and OECM1 RAD51 OE cells were stained with a combination of annexin V and PI and analyzed by FACS. Cells positive for annexin V and PI staining were counted as apoptotic cells. The bar chart describes the percentage distribution of apoptotic cells. OECM1 RAD51 OE cells have less apoptotic cells at 72 h after 10 Gy irradiation than OECM1 EV cells, (E) XTT assay in OECM1 EV and OECM1 RAD51 OE cells at 48 h after treatment with difference doses of cisplatin and RAD51 OE cells survived better after cisplatin treatment, (F) XTT assay in OECM1 EV and OECM1 RAD51 OE cells at 72 h after cisplatin treatment and RAD51 OE cells survived better after cisplatin treatment, (G) OECM1 EV and OECM1 RAD51 OE cells were stained with a combination of annexin V and PI and analyzed by FACS. OECM1 RAD51 OE cells have less apoptotic cells at 72 h after treatment with 5 µg/ml cisplatin

Gy, gray; *, P < 0.05; **, P < 0.01; ***, P < 0.001