CNR2 and HIV infectious disease: Therefore, the reciprocal effects exerted by HIV infection and the CB2 receptor may explain the different association of severe liver necroinflammation and the CB2 variants: CB2 RR in HIV/HCV coinfected patients who show an aggressive disease with a rapid progression to liver cirrhosis and hepatocellular carcinoma and CB2 QQ in HCV-monoinfected patients with an asymptomatic indolent course of the liver disease.