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Differential expression of new splice variants of the neurotensin receptor 1 gene in human prostate cancer cell lines.

Laboratorio de Genética, Instituto Universitario de Enfermedades Tropicales de Canarias, Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez s/n, 38206 La Laguna, Canarias, Spain.
Peptides (Impact Factor: 2.61). 12/2009; 31(2):242-7. DOI: 10.1016/j.peptides.2009.12.007
Source: PubMed

ABSTRACT Neurotensin is a neuroendocrine peptide acting as a trophic factor in a variety of cells in vivo but it can also function as an autocrine growth factor in human prostate cancer cells in vitro. In addition, the high-affinity G protein-coupled NT receptor (NTS1) is overexpressed in prostate cancer cell lines. Increasing evidence argues for a direct correlation between specific alternative splice variants and cancer. We detected four splice variants of the NTS1 receptor in human prostate cancer cell lines. These isoforms include one or more exons skipping as well as an alternative 5' splice donor site and are expressed in the late-stage androgen independent prostate cancer cell lines PC3 and DU145, but not in the early-stage androgen-sensitive LNCaP or in normal prostate tissue, which only express the normal transcript. This result shows new splice variants of NTS1 for the first time. The differential expression observed among prostate cancer cell lines and normal prostate tissue opens the interesting possibility of a new role of NT/NTS1 pathway in prostate cancer.

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