Figure 1.

Repeated low-dose NaAsO₂ exposure resulted in increased proliferative capability and MMP9 expression in HaCat cell. Cells were continuously exposed to NaAsO₂ for 15 weeks at the concentration of 0, 0.05, and 0.1 μmol/L. A total of three sets of cells were established. (A) Cell photos taken before long-term culture and after culture for 15 weeks. No morphological alterations were observed in the NaAsO₂ exposed cells. (B) For each set of the cell, cell proliferation was analyzed by CellTiter 96 assay. Similar results were obtained from the three sets of cells. A representative figure was presented. The NaAsO₂ exposed cells showed increased proliferative capability, which could be attenuated by MK2206 (10 μmol/L, 24 h). (C) The expression of MMP9 was analyzed by Western Blot assay. Long-term NaAsO₂ exposure resulted in increased expressions of MMP9 in the HaCat cells, which could be attenuated by the treatment of MK2206 (10 μmol/L, 24 h). Significant difference was defined as p less than 0.05. a, vs. the corresponding 0 μM group; b, vs. the corresponding 0.05 μM group; c, vs. the MK2206(-) group of the same NaAsO₂ concentration.