Analysis of PTEN mutations and deletions in B-cell non-Hodgkin's lymphomas

The PTEN gene is involved in 10q23 deletions in several types of cancer, in cluding glioma, melanoma, endometrial and prostate carcinomas. The PTEN gen e product is a dual-specificity phosphatase with putative tumor suppressor function. Deletions and rearrangements of 10q22-25 have been reported in si milar to 5%-10% of non-Hodgkin's lymphomas (NHLs), raising the possibility of PTEN involvement in these tumors. In order to address this question, we analyzed a panel of NHLs (n = 74) representative of the main histologic sub types for mutations and homozygous deletions of PTEN. We report somatic cod ing/splice site mutations in 20% (2 of 10) of Burkitt's lymphoma cell lines and in 3% (2 of 64) of primary NHL cases analyzed. No homozygous deletions were found in these tumors. Interestingly, this study showed that cytogene tically characterized NHL cases (n = 6) with 10q22-q25 abnormalities displa yed neither biallelic deletions nor mutations of PTEN. These results sugges t that a tumor suppressor gene distinct from PTEN may be involved in 10q de letions in this subgroup of NHL cases. Genes Chromosomes Cancer 24:322-327, 1999. (C) 1999 Wiley-Liss, Inc.