DELETION IN HUMAN-CHROMOSOME REGION 12Q13-15 BY INTEGRATION OF HUMAN PAPILLOMAVIRUS DNA IN A CERVICAL-CARCINOMA CELL-LINE

In human cervical carcinomas papillomavirus DNA is frequently integrat ed in the cell genome, We have cloned the integration site of human pa pillomavirus-18 DNA in human chromosome region 12q13-15 present in the SW756 cervical carcinoma cell line. Viral DNA is broken from nucleoti des 2643 to 3418 in the El and E2 open reading frames, resulting in a deletion of 775 bases of viral DNA, Cloning and sequence analysis of t he rearranged and germline alleles shows that there is no homology bet ween the target cellular and viral DNA, suggesting it is a nonhomologo us recombination. The target cellular region is called papillomavirus associated locus 2 (PAL2). The 5'- and 3'-flanking probes derived from the hybrid viral-cellular clone detect completely different germline restriction fragments in DNA from cells with normal chromosome 12. The re is no overlap between the restriction maps of the target germline c lones obtained with 5'- and 3'-flanking probes. Probes from these germ line clones beyond the breakpoint position do not detect any DNA rearr angement in SW756 cells DNA. These data prove that there is a deletion of cellular DNA as consequence of the integration, with an estimated minimum size of 14 kilobases, Both cellular flanking probes are outsid e the amplicon of this chromosome region identified in the OSA and RMS 13 sarcoma cell lines, comprising SAS-CHOP-CDK4-MDM2 genes and where t ranslocation breakpoints are located in liposarcomas. The integration at 12q13-15 might have been selected by its contribution to the tumor phenotype.