The studies of hepatitis B virus X gene induces oval cell malignant transformation

Abstract

To find out the mechanisms of HBx gene inducing oval cell malignant transformation into hepatoma carcinoma cell. The changes of morphology, cell cycle, differentiated markers, c-myc and TGF-alpha in pEGFP-HBx oval cells strain, which stably expressed HBx gene, were studied by inversion phase contrast microscope and transmission electron microscopy, flow cytometry, periodic acid-schiff (PAS) staining, soft agar growth assay, real-time PCR, immunocytochemistry. pEGFP-oval cells and LE/6 oval cells were used as control groups. (1) The pEGFP-HBx oval cells showed bigger in size with malformed nucleus as compared with control groups. (2) Flow cytometry showed that, in contrast with the control groups, the proportion of pEGFP-HBx oval cells arrested in G0/G1 phase decreased but in S or G2/M phase rose. Moreover, the population of aneuploid cells increased obviously. (3) PAS staining showed that there were many glycogen granules in the cytoplasm of pEGFP-HBx oval cell. (4) The pEGFP-HBx oval cell formed colonies in the soft agar. (5) Compared with the control groups, the expression of HNF-4 alpha, AFP, c-myc and TGF-alpha rose obviously, whereas the expression of CK-7 and CK-19 decreased. And the expression of cps1 mRNA was not in the extent of detection. The HBx gene can provoke abnormal differentiation of oval cell and induce oval cell malignant transformation.