Fig.3 Effect of combined metformin and cisplatin treatment on thymidine incorporation in Ishikawa cells cultured at different O2 levels.

(A) In cells cultured under normoxic conditions(21% O2), higher concentrations of metformin resulted in a greater reduction in thymidine incorporation relative to cells treated with cisplatin only.
(B) The additive effects of metformin and cisplatin were attenuated under hypoxic conditions(1% O2). Data are shown as mean ± standard error of six samples from three independent experiments. *P＜0.005 and **P＜0.001. From Uehara et al., modified with permission［22］. MET: metformin, CDDP: cisplatin.