Integration of SV40 at 12q23 in SV40-immortalized human bronchial epithelial cells

In four SV40-immortalized human bronchial epithelia] cell lines established in our laboratory, we identified the SV40 integration sites by fluorescence in situ hybridization. We found that in the late passage of all the four cell lines, SV40 integrated at 12q23. It is possible that only SV40 integration at 12q23 is necessary for the immortalization of human bronchial epithelial cells. Some DNA sequences or genes in the region, such as IGF-1, may be involved with a proliferative advantage of the cells with 12q23 SV40 integration.