Fig. 10

Inhibition of GSK3β activity reversed the inhibition of colony formation and carcinogenesis development in curcumin in AsT cells. A BEAS-2B cells were maintained in a medium containing As³⁺ (0 or 0.5 μM) for 9 months, after As³⁺-induced BEAS-2B cells transformed, the transformation cells were treated with or without curcumin (B) and/or 5 μM SB216763 (C) for 1 week. Cells were cultured in 0.35% soft agar for 5 weeks. Colony numbers in the entire dish were counted. D AsT cells treated as indicated from different treatments were injected into the flanks of 6-week old athymic nude mice (1 × 10⁶ cells per mouse) and checked daily for tumor appearance; tumor volume (E) and weight (F) was measured after 21 days injected. Tumor volume was determined by Vernier caliper, following the formula A × B2 × 0.52, where A is the longest diameter of tumor and B is the shortest diameter. The data are expressed as the mean ± SD of three independent experiments (n = 9). *p < 0.05, **p < 0.01 versus AsT cells control group. G Angiogenic (HIF1α and VEGF) markers and Nrf2 were decreased in tumors treated with both As³⁺ and curcumin, while inhibition of GSK3β could reverse the inhibition effects of curcumin as evident from immunohistochemistry. Frozen tumor Sections (5 μM thick) were subjected to immunoperoxidase staining (dark brown) to detect HIF1α, VEGF, and Nrf2 expressions. The data are expressed as the mean ± SD of three independent experiments (n = 9). *p < 0.05, **p < 0.01 vs control