Fig 6. Chemo-resistant cancer cell lines often do not show cross-resistance to COTI-2.

Paclitaxel-resistant (A) and cisplatin-resistant (B) A549, DMS-153, and SHP-77 cells were exposed to IC₅₀ concentrations of COTI-2 and tumor cell proliferation was measured after approximately 4 doublings of control cells. 5FUdR-resistant HeLa cells (C) and vincristine-resistant HN-5a cells (D) were exposed to IC₅₀ concentrations of COTI-2 as described in (A) and (B). Significant differences were assessed by Student’s t-test (p<0.05). Data indicates mean values derived from 3 independent experiments ± SEM.