Activation of c-Met in cancer cells mediates growth-promoting signals against oxidative stress through Nrf2-HO-1

c-Met induction protects the renal cancer cells from sorafenib-induced ROS generation, DNA damage, and apoptosis. a–f 786-O cells were subjected to combination treatments with HGF (50？ng/ml), sorafenib (10？μM) or only vehicle for 24？h. a Apoptotic cell deaths were measured by annexin V (APC) and propidium iodide staining through flow cytometry. b Cell proliferation was measured by MTT assay. c Following treatment, cells were stained by using oxidative stress detection reagent and checked for endogenous reactive oxygen species (ROS) through flow cytometry. d–f Fractions of cellular lysates were utilized to analyze levels of Bcl-2, Bcl-xL, cleaved Caspase-3 (d); γ-H2AX (e) and HO-1 (f) by Western blot. β-Actin was used as an internal control (d–f). In a and c–f: Results are representative of three different experiments. In b: The columns are the mean？±？S.D. of triplicate readings from two different samples. *p？<？0.05 compared with vehicle-treated control cells, and #p？<？0.05 compared with cells treated with sorafenib alone. In d, the bar graphs under the Western blots represent the relative expression Bcl-2/Bcl-xL/Caspase-3 (cleaved) by densitometry, where the signals were normalized to the expression of an internal control β-Actin. The columns represent the average？±？S.D of relative intensities from three different blots. *p？<？0.05 compared with cells treated with sorafenib alon