Objective: To establish an immortalized cell line derived from the embryonic cervical epithelium by infection with the recombinant adeno-associated virus (rAAV) containing human papillomavirus (HPV)16 E6, E7, and to study the biological features of cervical cancer cell line.
Methods: Human embryonic cervical tissues were cultured in keratinocyte free serum (K-FS) medium and infected with rAAV containing HPV16 E6, E7. Morphological features and growth rate were examined by light, electronic and fluorescence microscopies. The fragments of E6, E7 were detected by polymerase chain reaction (PCR) and laser confocal microscopy. The biological characteristics of human cervical epithelium were observed by soft agar culture, scid mice inoculation and chromosome analysis. Cell proliferative dynamics was plotted by flow cytometry.
Results: After a long-term culture, the phenotype kept the characteristics of primary epithelial cells. They showed monolayer, anchorage-dependent and attachment-inhibited growth without forming colonies in soft agar culture. They were non-oncogenic when inoculated into scid mice. The tonofilament expression in the cervical cancer cells was inspected by electronic microscopy, demonstrating that the cells were squamous epithelium in origin. The cell line contained HPV16 E6, E7 genes by PCR and laser confocal detection. Chromosome analysis disclosed that the karyotype was diploid or polyploid. The 11th chromosome was assumed to be the integration site by rAAV containing HPV16 E6, E7.
Conclusions: Establishment of the immortalized cervical epithelial cell line by infection with rAAV containing HPV16 E6, E7, supports that HPV16 E6, E7 may be the primary etiology of cervical cancer. It will facilitate further research on the etiology and pathogenesis of cervical cancer.