Establishment and characterization of 12 uterine cervical-carcinoma cell lines: Common sequence variation in theE7 gene of HPV-16-positive cell lines

A total of 12 carcinoma cell lines of the human uterine cervix were established from 5 keratinizing and 5 nonkeratinizing squamous-cell carcinomas, and 2 small-cell carcinomas. Of these, 10 lines grew as adherent cells and 2 as floating aggregates. All lines showed (i) similarity in morphology to the primary tumor from which they were derived; (ii) high viability with relatively long doubling times (48-96 hr); (iii) absence of Mycoplasma and other bacteria, apart from one Mycoplasma-contaminated line; (iv) genetic heterogeneity by DNA-fingerprinting analysis; (v) absence of p53 mutation from exon 4 through 9; and (vi) the presence of HPV DNA sequence. Among the lines, 7 were infected by HPV-16, 3 by HPV-18, 1 by HPV-31, and 1 by HPV-33; the 2 cell lines derived from small-cell carcinomas contained HPV-18. Interestingly, 6 of the 7 cell lines containing HPV-16-type DNA harbored the same alteration of E7 at nucleotide position 647 (amino acid 29, AAT --> AGT, Asn --> Ser), whereas the 3 HPV-18-positive lines did not; 3 cell lines proved to have intact E1/E2 of HPV, suggesting the presence of episomally replicating HPV DNA as well as the integrated form, whereas the other 9 lines were shown to have integrated HPV. Taken together, these cell lines would be very useful for studying the biology of uterine cervical carcinoma.