MTHFR and intrahepatic cholangiocarcinoma: In this study, we comprehensively investigate the modulation of HPV infection, HSIL and ICC, and ICC through an exploration of oxidative stress-related genes: CβS, MTHFR, NOS3, ACE1, CYBA, HAP, ACP1, GSTT1, GSTM1, and CYP1A1.