title: Upregulated miR-9-3p Promotes Cell Growth and Inhibits Apoptosis in Medullary Thyroid Carcinoma by Targeting BLCAP.
abstract: Medullary thyroid carcinoma (MTC) is a neuroendocrine cancer derived from parafollicular C cells in the thyroid gland. It has great interest as a research focus because of its unusual genetic, clinical, and prognostic characteristics. However, the pathogenesis in MTC is not completely clear. We investigated the role of miR-9-3p and bladder cancer-associated protein (BLCAP) in MTC TT cells. First, miR-9-3p expression was upregulated in human MTC tissues and TT cells and compared to the control by RT-PCR. Flow cytometric analysis indicated that the cell cycle progression in TT cells was significantly inhibited by the miR-9-3p inhibitor but was increased by the miR-9-3p mimic. On the contrary, the apoptosis of TT cells was significantly increased by the miR-9-3p inhibitor and suppressed by the miR-9-3p mimic. A similar change pattern was observed in the expression of apoptosis-regulated protein caspase 3 induced by the miR-9-3p mimic or inhibitor in TT cells. We then identified that BLCAP is a target of miR-9-3p by bioinformatic prediction and luciferase reporter assay. The expression of BLCAP was also significantly downregulated by the miR-9-3p mimic while being upregulated by the miR-9-3p inhibitor in TT cells. Furthermore, we confirmed that the inhibited apoptosis of TT cells induced by the miR-9-3p mimic was enhanced by BLCAP overexpression. The levels of apoptosis were strongly decreased by BLCAP silencing in TT cells, which were not further influenced by the miR-9-3p inhibitor. In summary, upregulated miR-9-3p has a positive role in human MTC progression by regulating the growth and apoptosis of cancer cells via targeting BLCAP. This might represent a possible diagnosis or therapeutic target for MTC.
authors.forename: Yangjing
authors.initials: Y
authors.lastname: Chen
authors.forename: Shaoqiang
authors.initials: S
authors.lastname: Zhang
authors.forename: Ruimin
authors.initials: R
authors.lastname: Zhao
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhao
authors.forename: Ting
authors.initials: T
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis / Q000235:genetics; D018278:Carcinoma, Neuroendocrine / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D014162:Transfection; D015854:Up-Regulation
chemical_list: C453739:BLCAP protein, human; C541874:MIRN92 microRNA, human; D035683:MicroRNAs; D009363:Neoplasm Proteins