Enhanced p62-NRF2 Feedback Loop due to Impaired Autophagic Flux Contributes to Arsenic-Induced Malignant Transformation of Human Keratinocytes

Figure 5

Enhanced transcription and decreased protein turnover contribute to accumulation of p62 protein in response to arsenite exposure. (a) Western blot of NRF2 and p62 under basal and arsenite-treated conditions in SCR and NRF2-KD cells. As: cells were treated with 100 nM sodium arsenite for 6 h. PC: positive control, cells were treated with 20 μM sodium arsenite for 6 h. (b) mRNA levels of p62, NQO1, and GCLC in HaCaT cells treated with 100 nM sodium arsenite at different time points. (c) Exposure to arsenite inhibited p62 degradation in HaCaT cells. Cells were treated with CHX (10 μg/mL) or CHX+ As (100 nM) at different time points, followed by Western blot analysis. For Western blot, left: representative image; right: quantification of p62 protein levels. . , compared with Con compartment. ^#, compared with SCR compartment or CHX-treated compartment.

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