Effect Of Co-Expression Of Nuclear Transcription Factors On The Biological Characteristics Of Hepatocellular Carcinoma Cells

Accumulative evidence indicates that it is drug resistance and the ability of local recurrence and remote metastases that eventually kill the cancer patients.Recent reports demonstrate that introducing a set of four core nuclear factors is sufficient to reprogram somatic cells into induced pluripotent stem cells(iPSCs)and inactivation of p53 tumor suppressor pathway facilitates this reprogramming process.Given a high similarity in gene expression profiles and phenotypic characteristics between these i PSCs and CSCs,we hypothesized that nuclearreprogramming process plays a role in tumorigenesis.We therefore propose to explore the role of nuclear transcription factor in occurrence and development of human hepatocellular carcinoma by co-transfection of these core factors.To achieve this goal,we first screened a panel of core nuclear factors,including Oct3/4,c-Myc,Nanog,and Sox2,in a cohort of 85 tumor specimens obtained from patients with hepatocellular carcinoma(HCC).We found that all these core nuclear factors were detected in some of these tissue specimens and co-expression of these core factors at varying degrees were also observed in the HCC tissues.Based on these findings from HCC tissue samples as well as related reports in the literature,we selected a set of three factors,namely Sox2,c-Myc and HBx,as the first trial to test our hypothesis.In order to accelerate the transfection processes and selection efficiency of stable cells transfected with these three factors,we utilized a foot and mouth disease viral(FAMV)protein 2A fragment to synthesis a cistronic multi-gene expression system for a non-fusogenic expression of HBx,Sox2,and c-Myc genes in a single plasmid.After selection,we obtained a few stable clones with expression of these target genes.We then assessed the biological alterations in vitro among these stable cells with expression of the Sox2,and c-Myc,and tumorigenesis in nude mice in vivo.We observed that expression of these factors affected cell cycle progression,cell proliferation,cell survival,cell motility,3D sphere formation,as well as sensitivity to anti-cancer drugs in vitro,and tumorigenesis in vivo.