Promyelocytic Leukemia (PML) Gene Mutations may not Contribute to Gastric Adenocarcinoma Development

Gastric cancer is the second most common cause of cancer death worldwide. Environmental as well asgenetic factors have been shown to be involved in its genesis. Among genetic factors, loss of function of a tumorsuppressive gene named promyelocytic leukemia (PML) has been demonstrated in gastric cancer. In order to castlight in the mechanism by which PML protein is under-expressed in gastric cancer cells, we analyzed all exonsand intron-exon boundaries of PML gene in 50 formalin-fixed paraffin-embedded tissue blocks from gastriccarcinoma tumors by means of PCR-SSCP and CSGE, with direct sequencing of abnormally shifted bands.We found a novel sequence variant of unknown significance localized in intron 5 in 3 samples (c.1398+84delA).We did not detect any deleterious mutations of the PML gene. This study shows that PML mutations may notcontribute to gastric adenocarcinoma development. Post-translational modifications or protein degradationmight be mechanisms by which PML is not expressed in gastric tumors.