Heterologous Transplantation, Chromosome Analyses, and DNA Measurements of the Human Carcinoma Tissue Culture Line, H.Ep. #22

Publisher Website
Google Scholar
Abstract
The human epidermoid carcinoma No.2 (H.Ep. #2), which had been kept continuously in tissue culture since 1953, was transplanted into adult, conditioned golden hamsters. Morphologically, the transplanted tumors resembled closely the original tissue from the patient. Chromosome analyses were performed on two series of H.Ep. #2 cells, both originating from Fjelde stock cultures. The First series comprised the first stock culture from Fjelde (TCF), the corresponding First hamster tumor line (H.Ep. #2/H1), and material from the latter brought back into tissue culture (H.Ep. #2/H1-TC). The second series included the second tissue culture material (H.Ep. #2/TC2) and the ensuing second hamster tumor line (H.Ep. #2/H2). Chromosome numbers of cells of the first series varied between 69 and 80, with a large peak at 74–75 and a smaller peak at 77. Four marker chromosomes were present. In the second series, a large peak was found at 69–70 and a smaller peak at 74–75. Besides the 4 markers from the First series, the cells within these peaks possessed 2 new markers, each of them characteristic for one of the peaks. The different peaks in the frequency distribution of the chromosome numbers were interpreted as representing 2 stemlines. In the first series this assumption was based on chromosome numbers only, whereas in the second series it was corroborated by the presence of the individual marker chromosomes. DNA was measured on Feulgenstained nuclei of H.Ep. #2 cells grown in vivo and in vitro. Both tumor cell lines showed their DNA values to be aggregated in two peaks: one around 3.5c and the other around 7c. Thus a correlation was established between the amount of DNA and the hypertriploid chromosome number of H.Ep. #2 cells.