NO OCCURRENCE OF DNA-POLYMERASE BETA-GENE MUTATION IN HUMAN LUNG-CARCINOMA CELL-LINES WITH K-RAS AS, P53, OR RB GENE ALTERATIONS

In order to investigate the relationship between a potential defect in the DNA repair system and human lung carcinogenesis, we examined the entire coding region of the human DNA polymerase beta gene using the r everse transcription-polymerase chain reaction (RT-PCR)/single-strand conformation polymorphism (SSCP) method in 31 human lung carcinoma cel l lines (18 non-small cell lung carcinoma (NSCLC) cell lines and 13 sm all cell lung carcinoma (SCLC) cell lines, 4 cell lines with K-ras poi nt mutation, 9 with p53 point mutation, 3 with retinoblastoma suscepti bility (Rb) gene alteration). Mutation of the polymerase beta gene was undetectable in all of them. These results suggest that mutations of the DNA polymerae beta gene is extremely rare if it occurs at all in h uman lung cancer, and may have no relation with K-ras, p53, or Rb gene alterations.