Biological characteristics of human hepatocellular carcinoma cell lines with or without prior nude mouse passages.
A cell line, J5, derived directly from the human hepatocellular carcinoma (HCC) by in vitro culture, and three other lines, J2-23, J3-27 and J3-28, which were established in culture only after passages in nude mice were examined. Since nude mice as well as various strains of normal mice often produce infectious murine retroviruses, the HCC cells passaged as a heterotransplant in nude mice may be infected with these viruses. The supernatant of the J2-23, J3-27 and J3-28 cell co-cultured with a wild mouse cell line, SC-1, which supports the murine ecotropic retroviruses, showed the presence of a murine N-tropic virus. No murine xenotropic retrovirus was detected in these cells using S+L- mink cell assay method. A clone (J3-28 Clone 1) was derived from the above mentioned J3-28 cells, since the latter contained a mixture of human and murine cells. The J3-28 Clone 1 was found to be entirely of human karyotype. This clone as well as the J5 and the PLC/PRF/5 cel lines which have never been passaged in nude mice, showed none of these murine retroviruses. By Southern-blot hybridization, no change was detectable for c-abl, c-ras, c-mos, and c-myc protooncogenes in the chromosomal DNA of J2-23, J3-27, J3-28 Clone 1, and J5 cell lines. The karyotypes of all the HCC cell lines were aneuploid, and those of the J2-23 and J3-27 cell lines were of mouse, while the J3-28 Clone 1 and J5 cell lines were of human. The chromosomes of the J2-23 and J3-27 cells showed, except for the presence of a few marker chromosomes in the former, no apparent changes in the length were observed. In contrast, those of the J3-28 Clone 1 and J5 cells exhibited various changes, including 6-8 marker chromosomes, and an increase or decrease in the length of p and/or q arms of various chromosomes.