PRDM5 is silenced in human cancers and has growth suppressive activities

Several genes that contain the PR (PRDI-BF1 and RIZ) domain have been linked with human cancers. We describe here a new PR-domain-containing gene designated as PRDM5 (PFM2). A PRDM5 cDNA was isolated based on its homology to the PR domain of RIZ1 (PRDM2). The gene encodes an open reading frame of 630 amino acids and contains a PR domain in the NH-terminal region followed by 16 zinc finger motifs. Radiation hybrid analysis mapped PRDM5 to human chromosome 4q26, a region thought to harbor tumor suppressor genes for breast, ovarian, liver, lung, colon, and other cancers. The gene has a CpG island promoter and is silenced in human breast, ovarian, and liver cancers. A recombinant adenovirus expressing PRDM5 caused G2/M arrest and apoptosis upon infection of tumor cells. These results suggest that inactivation of PRDM5 may play a role in carcinogenesis.