Mapping an Endometrial Cancer Tumor Suppressor Gene at 10q25 and Development of a Bacterial Clone Contig for the Consensus Deletion Interval

Frequent loss of chromosome 10q sequences in endometrial cancers suggests the involvement of a tumorsuppressor gene. Previous loss-of-heterozygosity (LOH)studies have pointed to the 10q25–q26 region as the likely site of a tumor suppressor involved in endometrial tumorigenesis (S. L. Peifferet al.,1995,Cancer Res.55: 1922–1926; S. Nagaseet al.,1996,Br. J. Cancer74: 1979–1983; S. Nagaseet al.,1997,Cancer Res.57: 1630–1633). In an attempt to define further the localization of a tumor suppressor gene at 10q25, we screened a panel of 123 endometrioid adenocarcinomas for loss of heterozygosity of 10q25.3 sequences. Forty-three (35%) revealed LOH at one or more loci. The observed patterns of allelic loss define a minimum consensus region of deletion between D10S221 and D10S610. A sequence-ready bacterial clone contig and a long-range restriction map for a 1-Mb interval spanning the deletion region were developed as the first step in experiments directed toward the discovery the 10q25 tumor suppressor.