APOB and psoriasis: When patients were stratified by sex, MTX significantly downregulated the levels of serum ApoB, TC, and Lp(a) in both male and female patients with psoriasis, and differentially reduced the levels of serum ApoA1, HDL-C, LDL, and ratios of ApoB/ApoA1 and LDL/ApoB in male patients with psoriasis, but not in female patients.