Culture of a cell line (nclp-6) derived from a hepatocarcinoma induced in macaca mulatta by n-nitrosodiethylamine

A continuous cell culture line was established from a hepatocarcinoma induced in a rhesus monkey by N-nitrosodiethylamine. Results of intracerebral transplantation of cells of this line were described previously (J Nat Cancer Inst 39: 153–169, 1966). Line NCLP-6 has now been in continuous culture for 3½ years, through over 70 subcultures, and has been preserved frozen for as long as 28 months. A variant subline, NCLP-6-F, evolved from the parent line, NCLP-6-E, at the 26th subculture. The F subline grows more rapidly, has fibroblastoid morphology, and lacks significant cytoplasmic alkaline phosphatase. The E subline retains epithelium-like morphology and exhibits alkaline phosphatase activity in granular distribution in the cytoplasm. When retained in culture vessels after monolayer formation is complete, the E subline forms simple micropapillary and polypoid structures, with palisading of epithelium on the outer layers of cell masses. In karyotype, both the E and F sublines are subtriploid and both have a large percentage of cells with 2 marker chromosomes: 1 large metacentric and 1 small acrocentric. However, the modal number of the F subline is 56, while that of the E subline is 59. The E subline is characterized by trisomy of chromosome #20, which is disomic in subline F.