EPDMNQ and ENDMNQ regulate mitochondrial, MAPK and STAT3 signaling pathways-associated proteins in Hep3B cells. (A) Hep3B cells were treated with EPDMNQ or ENDMNQ for different time intervals (3, 6, 12 or 24 h). The expression levels of mitochondrial pathway-associated proteins were analyzed by western blot analysis. (B) The expression levels of MAPK and STAT3 pathway-associated proteins were analyzed by western blot analysis. α-tubulin was used as the internal control. Band intensity was quantified using the Image J software. **P<0.01 and ***P<0.001 vs. untreated control group. EPDMNQ, 2,3-dihydro-2,3-epoxy-2-propylsulfonyl-5,8-dimethoxy-1,4-naphthoquinone; ENDMNQ, 2,3-dihydro-2,3-epoxy-2-nonylsulfonyl-5,8-dimethoxy-1,4-naphthoquinone; Bcl-2, B-cell lymphoma 2; Bax, Bcl-2-associated X protein; cle, cleaved; PARP, poly (adenosine 5-diphosphate-ribose) polymerase; p, phosphorylated; p38, p38 mitogen-activated protein kinase; JNK, c-Jun N-terminal kinase; ERK, extracellular signal regulated kinase; STAT3, signal transducer and activator of transcription 3.