Abstract: Background and purpose: Esophageal squamous cell carcinoma (ESCC) is a common gastrointestinal malignant tumor, in which abnormal gene expression is involved in the malignant biological behavior of ESCC. This study aimed to investigate the expression level of transforming growth factor-β1 (TGF-β1)-induced FAM83H in ESCC and its relationship with clinicopathological characteristics, and to explore the effects of FAM83H on biological behavior of esophageal cancer cells in vitro. Methods: The cell morphology was measured under an inverted microscope in TGF-β1-treated Eca109 cells. The expression levels of epithelial-mesenchymal transition (EMT)-related markers and FAM83H were detected in TGF-β1-treated cells compared with untreated cells by real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR). The expression level of FAM83H in different esophageal cancer cell lines and 67 pairs of ESCC tissues and corresponding normal tissues collected from the biological sample bank of the Fourth Hospital of Hebei Medical University from 2015 to 2017 were detected by RTFQ-PCR, and the associations between FAM83H expression level and clinicopathological characteristics were also analyzed. The effects of FAM83H on proliferation, migration and invasion of esophageal cancer cells were examined by MTS, transwell migration, and invasion assays. Results: The cells underwent morphological changes to a spindle-shaped and slender appearance in TGF-β1-treated cells and showed obvious mesenchymal cell morphology. Besides, Eca109 cells treated with TGF-β1 displayed decreased expression level of E-cadherin, as well as upregulated expression levels of N-cadherin, vimentin, Snail and Twist 1 (P<0.05). Meanwhile, upregulation of FAM83H was detected in TGF-β1-treated cells (P<0.01). The expression level of FAM83H was significantly upregulated in ESCC (P<0.05), and was correlated with pathological differentiation (P<0.05). The expression level of FAM83H was also elevated in esophageal cancer cell lines (P<0.01). FAM83H expression level was also markedly inhibited by transfecting small interfering RNA (P<0.05). FAM83H reinforced esophageal cancer cell proliferation, migration and invasion (P<0.05). Conclusion: TGF-β1 induced EMT and FAM83H expression. The high expression level of FAM83H may be related to the occurrence and development of ESCC, and promoted the proliferation, migration and invasion of esophageal carcinoma cells in vitro.

Key words: FAM83H, Esophageal squamous cell carcinoma, Biological characteristics, Epithelial-mesenchymal transition