STMN2 overexpression promotes cell proliferation and EMT in pancreatic cancer mediated by WNT/β-catenin signaling.

STMN2, as a key regulator in microtubule disassembly and dynamics, has recently been shown to participate in cancer development. However, the corresponding role in pancreatic ductal adenocarcinoma (PC), to our knowledge, has not been reported yet. In the current study, we systematically investigate the potential role of STMN2 in the progression of PC in vitro and vivo. Overexpression of STMN2 was prevalently observed in 81 human cases of PC tissues compared with that in the paired adjacent pancreas (54.3% vs 18.5%, P < 0.01), which was positively associated with multiple advanced clinical stages of PC patients (tumor size, T stage, lymph-node metastasis and the poor prognosis). Meanwhile, a close correlation between high STMN2 and cytoplasmic/nuclear β-catenin expression (P = 0.007) was observed in PC tissues and cell lines. STMN2 overexpression induced EMT and cell proliferation in vitro via stimulating EMT-like cellular morphology, cell motility and proliferation, and the change of EMT (Snail1, E-cadherin and Vimentin) and Cyclin D1 signaling. However, XAV939 inhibited STMN2 overexpression-enhanced EMT and proliferation. Conversely, KY19382 reversed STMN2 silencing- inhibited EMT and cell proliferation in vitro. Furthermore, activated STMN2 and β-catenin were co-localized in cytoplasm/nuclear in vitro. β-catenin/TCF-mediated the transcription of STMN2 by the potential binding sites (TTCAAAG). Finally, STMN2 promoted subcutaneous tumor growth following the activation of EMT and Cyclin D1 signaling. STMN2 overexpression promotes the aggressive clinical stage of PC patients and promotes EMT and cell proliferation in vitro and vivo. β-catenin/TCF-mediated the transcription of STMN2.