Endogenous Leu332Gln mutation in p53 disrupts the tetramerization ability in a canine mammary gland tumor cell line.

Endogenous Leu332Gln mutation in p53 disrupts the tetramerization ability in a canine mammary gland tumor cell line. Oncol Rep. 2018 May 02;: Authors: Ochiai K, Azakami D, Morimatsu M, Hirama H, Kawakami S, Nakagawa T, Michishita M, Egusa AS, Sasaki T, Watanabe M, Omi T Abstract Mutations in the p53 gene are associated with more than half of all human cancers. These mutations often cause a disruption of the tumor-suppressor function of p53 and induce genomic instabilities. Wild‑type p53 requires tetramerization to function as an initiator of cell cycle arrest and apoptosis. Although alterations in p53 tetramerization caused by mutation have been well studied, there are few cell lines containing an endogenous mutation in the tetramerization domain of p53. Here, we report the discovery of a canine mammary gland tumor cell line CTB‑m2, which contains the Leu332Gln (L332Q) mutation corresponding to Leu344 in the tetramerization domain of human p53. Although CTB‑m2 cells are genetically heterozygous for the Leu332Gln mutation, the mutant mRNA was almost exclusively expressed. CTB‑m2 cells showed enhanced cell proliferation compared to wild‑type p53-expressing CTB‑m cells of the same lineage. A p53 tetramerization reporter assay showed that the ability of the p53 mutant to form tetramers was significantly lower than that of wild‑type p53. An immunoblot analysis of cross-linked p53 oligomerized forms demonstrated that the L332...
Source: Oncology Reports - Category: Cancer & Oncology Tags: Oncol Rep Source Type: research