Figure 1.

Effect of benzene and its metabolites on human PTPN2 activity. A, schematic representation of the benzene bioactivation pathway (1). B, human PTPN2 was incubated with increasing concentrations of benzene (BZ), phenol (PH), hydroquinone (HQ), or 1,4-benzoquinone (BQ) (0–200 μm) for 20 min at 37 °C, and residual PTPN2 activity was measured using a pNPP assay. Error bars, S.D. values. C, human PTPN2 was incubated with or without BQ (10 μm) or HQ in the presence of an active or inactive MPO hydroquinone-bioactivation system (including H₂O₂) for 20 min at 37 °C prior to residual PTPN2 activity assay. Error bars, S.D. *, p < 0.05 compared with control (Ctrl).