Spontaneous Neoplastic Transformation of WB-F344 Rat Liver Epithelial Cells (original) (raw)
Related papers
Phenotypic Modulation during Tumorigenesis by Clones of Transformed Rat Liver Epithelial Cells
Cancer Research, 1987
From nine clonal subpopulations (strains) of chemically transformed cultured rat hepatic epithelial cells which were tumorigenic when im planted into 1-day-old isogeneic rats, a cell line was reestablished from each tumor and the cellular properties of the tumor-derived cell lines were compared to those of the corresponding progenitor cells that were implanted to produce the tumors. In seven of eight instances, the cellular DNA content of the tumor-derived cells was virtually identical to the DNA content of the respective progenitor cells, but in one case the tumor cells had twice as much DNA as did their progenitor cells. During the development of tumors in viva, other cellular phenotypic properties often underwent considerable, but variable changes. These changes included the activity of •v-glutamyl transpeptidase, the growth properties on plastic surfaces, and the expression of LDH isozymes. Although there was a relative enhancement in the ability of most of the tumor-derived cells to proliferate or to form colonies in calcium-poor medium, several tumorderived cell lines had very low colony-forming efficiencies in media containing either normal or low levels of calcium. The most consistent association between phenotypes expressed in vitro and tumorigenicity was the ability of cells to form colonies in soft agar; all tumor-derived lines expressed this phenotype, and with some of them this phenotype was acquired only during the process of tumor formation in vivo. These results demonstrate that further phenotypic and genotypic alterations may occur in vivo during tumor formation by chemically transformed cultured cells following their implantation into isogeneic animals; and some of the alterations that occur in vivo may be necessary for the complete expression of tumorigenicity. Although anchorage-independent growth capacity cannot be used to predict the tumorigenicity of clones of rat liver epithelial cells chemically transformed in vitro, this growth property appears to be invariably induced prior to or during the formation of tumors in vivo by these cells.
Stem Cells and Development, 2010
Non-tumorous liver tissue removed during surgery to resect hepatocellular carcinoma (HCC) is potentially a useful source of material from which cells, particularly liver progenitor/stem cells (LPCs), can be isolated to establish cell lines. The purpose of this study was to evaluate the applicability of the "plate-and-wait" method to derive LPCs from resections to remove HCC. Three independent non-tumorous liver samples from HCC resection and 3 samples from liver donors were used for LPC isolation. Staining for LPC markers, OV6, CK19, and EpCAM, in the above liver samples demonstrated staining in only 2 of the non-tumorous samples. We isolated 2 human liver epithelial cell lines (HLECs) from these 2 samples. These HLECs were positive for general stem cell markers CD133, EpCAM, and Oct4. They expressed the liver progenitor cell markers OV6, CK14, and M2PK but not CK19. They also expressed the hepatocellular markers albumin, CK8, CK18, HNF4-α, and the drug-metabolizing gene CYP3A4. These cells accumulated glycogen, indocyanine green, and synthesized urea. They produced colonies in soft agar that showed anchorage-independent growth and their tumorigenic status was confi rmed when they produced tumors following transfer to athymic nude mice. In contrast, the third nontumorous tissue and 3 normal liver samples did not produce cell lines. This study establishes a correlation between the presence of LPCs in the source liver tissue and the ability to derive cell lines from these tissues. The phenotypic similarities between the LPCs and the HLECs suggest that a precursor-product relationship may exist between the 2 cell types.
American journal of surgery, 2017
Rat liver epithelial (RLE) cells could inhibit the proliferation and invasiveness of hepatoma cells in vitro. This study is to understand the tropism and the effect of RLE cells on mouse hepatoma cells both in vitro and in vivo. RLE cells were isolated from new-born rats and characterized their stem cell markers. Co-culture and HCC mouse model was established to detect therapeutic effect of RLE cells. RLE cells (including Thy-1+ RLE cells, Thy-1- RLE cells, RLE cells) displayed a selective tropism toward ML-1 hepatoma cells both in vitro and in vivo. They altered the gene expression of some cancer stem cell markers in the liver tumor. Liver epithelial cells have a selective tropism toward HCC in vitro and in vivo. They could alter the gene expression of cancer stem cells.
Liver Development, Regeneration, and Carcinogenesis
Journal of Biomedicine and Biotechnology, 2010
The identification of putative liver stem cells has brought closer the previously separate fields of liver development, regeneration, and carcinogenesis. Significant overlaps in the regulation of these processes are now being described. For example, studies in embryonic liver development have already provided the basis for directed differentiation of human embryonic stem cells and induced pluripotent stem cells into hepatocyte-like cells. As a result, the understanding of the cell biology of proliferation and differentiation in the liver has been improved. This knowledge can be used to improve the function of hepatocyte-like cells for drug testing, bioartificial livers, and transplantation. In parallel, the mechanisms regulating cancer cell biology are now clearer, providing fertile soil for novel therapeutic approaches. Recognition of the relationships between development, regeneration, and carcinogenesis, and the increasing evidence for the role of stem cells in all of these areas, has sparked fresh enthusiasm in understanding the underlying molecular mechanisms and has led to new targeted therapies for liver cirrhosis and primary liver cancers.
Hepatology, 1998
The genomic evolution of a cohort of WB-F344 rat liver epithelial cell lineages undergoing spontaneous neoplastic transformation was followed to define the mechanistic relationship between genomic instability and progression to the neoplastic phenotype. Eighteen independent populations of WB-F344 cells (initiated from a single diploidfounding population) were subjected to 12 cycles of selective growth at confluent cell density, and cellular DNA contents were measured after each selection cycle. Flow cytometry demonstrated significant gains in the amount of G 1 DNA after selection cycles 3, 6, and 7 in 44% (8 of 18), 89% (16 of 18), and 39% (7 of 18) of the cell populations, respectively. All populations subsequently lost DNA and returned to a diploid or pseudo-diploid DNA content within 1 to 2 selection cycles after the appearance of an increased DNA content. Additionally, appearance and subsequent disappearance of aneuploid or tetraploid subpopulations was observed in 11% (2 of 18) and 83% (15 of 18) of the experimental lineages, respectively. Although perturbations of G 1 DNA content were apparent as early as selection cycle 3, at least 8 cycles of selective growth were required for the acquisition of tumorigenicity. While the independent lineages demonstrated significant fluctuations in G 1 DNA content between selection cycles 3 and 8, the majority (11 of 13) of the populations contained a diploid or pseudodiploid DNA content at the time tumorigenicity was expressed. Genomic instability preceded the acquisition of tumorigenic potential in rat liver epithelial cells subjected to selective growth conditions of maintenance at confluence, and may be required for its expression. (HEPATOLOGY 1998;28:78-85.)
Scandinavian journal of gastroenterology, 2013
Objective. Liver regeneration following hepatectomy can stimulate the growth of hepatocellular carcinoma (HCC), and major hepatectomy can be associated with activation of hepatic progenitor cells (HPCs). The aim of this study was to evaluate how HPCs influence the malignant potential of tumor cells in vitro and HCC tumor growth after surgery in a rodent model. Material and methods. Hepatoma cells (JM1) were cultured with conditioned medium (CM) from syngeneic HPCs (WB-F344). Growth rate, resistance to Adriamycin, and expression patterns for invasiveness and stemness were compared with naïve JM1. Microscopic HCC tumors from naïve JM1 or JM1 cultured with CM were inoculated in Fischer 344 rats undergoing 70% hepatectomy with or without simultaneous infusion of WB-F344. Tumor growth and invasiveness-related factors were compared. Buffalo rats were induced with Morris hepatoma cells. Liver tissue from both in vivo models was examined with regard to activation of cells with progenitor-like phenotype. Results. Co-culture with CM resulted in an increased resistance to Adriamycin and enhanced expressions of a-FP, MMP9, ABCG2, CD133, and SOX2, as well as the activation of ERK, AKT, WNT, and TGF-b1 pathways. Tumor size and metastases were significantly higher in groups with co-cultured cells or HPCs infusion. After 70% hepatectomy and tumor implantation, cells positive for a-FP, CK19, and CD133 were found, thus suggesting a progenitor-like phenotype in the setting of epithelial-mesenchymal transition. Conclusion. HPCs have a marked effect on HCC cells in vitro and appear to stimulate the growth and malignant potential of experimental HCC tumors.
Cancer Research
The pattern of gene expression in fetal hepatocytes transformed in culture with a hepatocarcinogen (FRL cells) is studied with respect to a range of markers which are either developmental!)1 regulated and/or shown to be expressed at high levels in hepatoma cells. The relative abundance of the respective mRNAs is determined and immunocytochemistry is used to detect the respective proteins in cultured cells. When compared with its normal counterpart, FRL cells retain the expression of transferrin, a,-acid glycoprotein, T-glutamyltranspeptidase, and tyrosine aminotransferase at near normal levels, while expression of the liverspecific isoenzymes of pyruvate kinase (L form) and aldolase (B form) is reduced. The cell lines are different in that they fail to express albumin, a-fetoprotein, thiostatin and a:-macroglobulin, and they express high levels of M2-pyruvate kinase and aldolase A, markers often found in abundance in hepatoma cells. Therefore transformation has resulted in different effects on different genes. Furthermore, it is of interest to find that the cells coexpress both forms of the pyruvate kinase isoenzymes which does not occur in the normal developing hepatocyte.