Hepatocellular carcinoma ( HCC) is a prevalent primary liver cancer that is driven by cumulative chan-ges in the hepatocyte genome which were influenced by the liver microenvironment .The tumor microenvironment is a dynamic system, including cancer cells, stroma, the extracellular matrix.tissue hypoxia, diet, gastrointestinal tract ( GIT) microflora and circulating microvesicles , The liver microenvironment plays a pivotal role in HCC tu-merigenesis , progression and therapeutic efficienry .The study of the HCC microenvironment will provide new in-sights into the mechanism of tumourigenesis and potential novel targets in the treatment of HCC .

Objective To find out the physical state of the human papillomavirus ( HPV) genome in hepatoma cell line HepG2 cells and the regulation of HPV late capsid protein 1 ( L1) expression and to explore the nature of the cytoryctes in HepG2 cells.Methods E2 and E6 in HPV18 were detected by PCR to evaluate the physical state of HPV18 genome .HepG2 L1 expression was detected by ELISA , light microscropy and electron microscrope immu-nohistochemistry assays , Western blot assay using HPV L 1 mice monoclonal antibody .L1 mRNA in HepG2 cells was detected by reverse transcriptional PCR ( RT-PCR) .Results PCR assay displayed that HPV DNA was inte-grated with HepG2 genome.ELISA assay showed that HPV L1 was present in lysate of HepG2 cells.Light micros-cropy demonstrated strong positive reaction in HepG2 cells.In microscopy, in the cytoplasm of partial HepG2 cells, there were lumpish cytorrhyctes materials which consists of very small and uniform particles and these parti -cles were marked by HPV L1 antibody labeled by colloidal gold .Western blot analysis showed a band at 56 ku dis-trict and it was L1 specific strap which demonstrated HPV 18 L1 was present in HepG2 cells.RT-PCR assay demon-strated the presence of L1 mRNA in HepG2 cells.Conclusions HepG2 cells are HPV18-positive HPV DNA ge-nome is integrated with HepG2 cells.HepG2 cells can express L1.The cytorrhyctes in HepG2 cells are composed of HPV18 L1 indicating that L1 can be expressed in HepG2.