PTPRM, a candidate tumor suppressor gene in small intestinal neuroendocrine tumors.

ABSTRACT: Small intestinal neuroendocrine tumors (SI-NETs) are small, slow growing neoplasms with loss of one copy of chromosome 18 as a common event. Frequently mutated genes on chromosome 18 or elsewhere have not been found so far. The aim of this study was to investigate a possible tumor suppressor role of the transmembrane receptor type tyrosine phosphatase PTPµ (PTPRM at 18p11) in SI-NETs. Immunohistochemistry, quantitative RT-PCR, colony formation assay and quantitative CpG methylation analysis by pyrosequencing were performed. Undetectable/very low levels of PTPRM or aberrant pattern of immunostaining, with both negative and positive areas, were detected in the majority of tumors (33/40), and a significantly reduced mRNA expression in metastases compared to primary tumors was observed. Both t

SUBMITTER: Barazeghi E 

PROVIDER: S-EPMC6687034 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature