SERPINE2 feedback regulates EGF/EGFR signaling in human papillary thyroid carcinoma cells.

Thyroid cancer (TC) is the most prevalent malignant tumor in the endocrine system. Serpin peptidase inhibitor clade E member 2 (SERPINE2) is closely associated with tumor metastasis. The aim of the present study was to investigate whether SERPINE2 forms a feedback loop with epidermal growth factor (EGF)/EGF receptor (EGFR) that regulates cellular processes in human papillary thyroid carcinoma (TPC­1) cells. Reverse transcription­quantitative PCR and western blotting were utilized to analyze the expression of SERPINE2. Cell proliferation ability was detected with a cell proliferation and cytotoxicity assay kit (MTT) and by clone formation assay. The proliferation markers, including proliferating cell nuclear antigen and Ki­67, were also investigated to analyze the proliferative activity of TPC­1 cells. Besides, cell migration and invasion were analyzed by wound healing and Transwell assays, respectively, while cell apoptosis was analyzed by TUNEL staining. The results showed that SERPINE2 expression was increased in TPC cells, and SERPINE2 and EGF/EGFR regulated each other. Furthermore, SERPINE2 overexpression and silencing regulated TPC cell proliferation, migration, invasion and apoptosis. Besides, an EGFR inhibitor blocked the effects of SERPINE2 overexpression on the aforementioned biological processes. Therefore, the present study confirmed that SERPINE2 formed a positive feedback with EGF/EGFR to regulate the proliferation, invasion and migration of TPC cells, possibly providing novel insights into potential therapeutic targets of papillary TC.