Oral cancer cell line ; tumorigenecity ; EGFR ; p53 gene ; HPV
Abstract
Oral cancer, of which 90% is squamous cell carcinoma (SCC), comprises 3-5% among human cancer incidences. Since genetic abnormalities of human cancer greatly depend on geographic differences, cultural and environmental backgrounds are thought to be closely related to carcinogenic process. In the present study we attempted to establish several oral cancer cell lines and examined their proliferating activities and the degree of differentiation. In vivo tumorigenicity was observed by the injection of tumor cells into nude mice skin. The status of p53 gene and HPV infection was analysed through PCR, SSCP and DNA cloning. The results are as follows:
1. We estabished 9 oral cancer cell lines, of which 5 are from oral squamous cell carcinomas and 2 from mucoepidermoid carcinomas. Among them 2 originated from metastased lymphatic nodes.
2. Mean doubling time of established cell lines was 24.7 hours. Cell lines derived from metastatic lymph node showed faster doubling time.
3. Seven cancer cell lines showed EGFR protein over expression.
4. Point mutations of p53 tumor suppressor genes were detected in 4 out of 9 oral cancer cell lines. Three cases showed transversion in exon 7 and one case showed
transition in exon 8.
5. HPV DNA was not detected from all cancer cell lines.
In the present study, we established cancer cell lines from Korean oral cancer patients and investigated their biological and genetic characteristics. Further experiments would be focussed on the study of carcinogenesis and cancer prevention.