Figure 8.

Oncogenic pathways in SK-BR-3 and MDA-MB-231 cells treated with Chaga extract in combination with platinum-based chemotherapeutics. (A) Left panel: representative Western blotting showing the expression of phosphorylated (p) HER1, pHER2, pRb protein (Ser 780), and β-actin (loading control) in SK-BR-3 cells left untreated (Ctrl) or treated with 0.25 mg/mL of digested Chaga extract (MW < 3500 Da) alone, 1µM cisplatin or its derivative 0.01 µM RJY13 alone, or their combination for 72 h. Twenty micrograms of proteins/well were loaded. Right panel: densitometric quantifications of pHER1, pHER2, and pRb expression, normalized on β-actin, are shown; data are presented as the mean ± SE of three repeats. (B) Left panel: representative Western blotting showing the expression of phosphorylated (p) Src, pRb protein (Ser 780), p53, and β-actin (loading control) in MDA-MB-231 cells left untreated (Ctrl) or treated with 0.25 mg/mL of digested Chaga extract (MW < 3500 Da) alone, 1 µM cisplatin or its derivative 0.01 µM RJY13 alone, or their combination for 72 h. Twenty micrograms of proteins/well were loaded. Right panel: densitometric quantifications of pSrc, pRb, and p53 expression, normalized on β-actin, are shown; data are presented as the mean ± SE of three repeats. * p < 0.05, ** p < 0.01, *** p < 0.001. ns: not significant. One-way ANOVA, followed by Dunnet’s multiple comparison test.