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Protein tyrosine phosphatase PTPN1 modulates cell growth and associates with poor outcome in human neuroblastoma.

ABSTRACT: BACKGROUND:Protein tyrosine phosphatases (PTPs) regulate neuronal differentiation and survival, but their expression patterns and functions in human neuroblastoma (NB) are scarcely known. Here, we have investigated the function and expression of the non-receptor PTPN1 on human NB cell lines and human NB tumor samples. MATERIAL/METHODS:NB tumor samples from 44 patients were analysed by immunohistochemistry using specific antibodies against PTPN1, PTPRH, PTPRZ1, and PTEN. PTPN1 knock-down, cell proliferation and tyrosine phosphorylation analyses, and RT-qPCR mRNA expression was assessed on SH-SY5Y, SMS-KCNR, and IMR-32 human NB cell lines. RESULTS:Knock-down of PTPN1 in SH-SY5Y NB cells resulted in increased tyrosine phosphorylation and cell proliferation. Retinoic acid-mediated differentiation of NB cell lines did not affect PTPN1 mRNA expression, as compared with other PTPs. Importantly, PTPN1 displayed high expression on NB tumors in association with metastasis and poor prognosis. CONCLUSIONS:Our results identify PTPN1 as a candidate regulator of NB cell growth and a potential NB prognostic biomarker.

SUBMITTER: Nunes-Xavier CE

PROVIDER: S-EPMC6911276 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Protein tyrosine phosphatase PTPN1 modulates cell growth and associates with poor outcome in human neuroblastoma.

Nunes-Xavier Caroline E CE Aurtenetxe Olaia O Zaldumbide Laura L López-Almaraz Ricardo R Erramuzpe Asier A Cortés Jesús M JM López José I JI Pulido Rafael R

Diagnostic pathology 20191214 1

<h4>Background</h4>Protein tyrosine phosphatases (PTPs) regulate neuronal differentiation and survival, but their expression patterns and functions in human neuroblastoma (NB) are scarcely known. Here, we have investigated the function and expression of the non-receptor PTPN1 on human NB cell lines and human NB tumor samples.<h4>Material/methods</h4>NB tumor samples from 44 patients were analysed by immunohistochemistry using specific antibodies against PTPN1, PTPRH, PTPRZ1, and PTEN. PTPN1 knoc ...[more]

PMID: 31837707

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Protein tyrosine phosphatase PTPN1 modulates cell growth and associates with poor outcome in human neuroblastoma.

Publications

Protein tyrosine phosphatase PTPN1 modulates cell growth and associates with poor outcome in human neuroblastoma.

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