KIFC3 promotes proliferation, migration and invasion of esophageal squamous cell carcinoma cells by activating EMT and β-catenin signaling.

Background: Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies. A total of 45 kinesin superfamily proteins (KIFs) have been identified in humans, among which several family members have demonstrated varied functions in tumor pathobiology different mechanisms, including regulation of cell cycle progression and metastasis. KIFC3 has microtubule motor activity and is involved in cancer cell invasion and migration, as well as survival. However, the role of KIFC3 in ESCC is still unknown.

Aim: To evaluate the role of KIFC3 in ESCC and the underlying mechanisms.

Methods: Expression of KIFC3 was evaluated in ESCC tissues and adjacent normal esophageal tissues. The prognostic value of KIFC3 was analyzed using Kaplan-Meier Plotter. Colony formation, EdU assays, cell cycle analysis, Transwell assay, immunofluorescence, and western blotting were performed in ESCC cell lines after transfection with pLVX-Puro-KIFC3-shRNA- and pLVX-Puro-KIFC3-expressing lentiviruses. A xenograft tumor model in nude mice was used to evaluate the role of KIFC3 in tumorigenesis. Inhibitor of β-catenin, XAV-939, was used to clarify the mechanism of KIFC3 in ESCC. To analyze the differences between groups, test and nonparametric tests were used. < 0.05 was considered statistically significant.

Results: Immunohistochemical staining indicated that KIFC3 was upregulated in ESCC tissues compared with adjacent normal tissues. Kaplan-Meier Plotter revealed that overexpressed KIFC3 was associated with poor prognosis in ESCC patients. Colony formation and EdU assay showed that KIFC3 overexpression promoted cell proliferation, while KIFC3 knockdown inhibited cell proliferation in ESCC cell lines. In addition, cell cycle analysis showed that KIFC3 overexpression promoted cell cycle progression. KIFC3 knockdown suppressed ESCC tumorigenesis . Transwell assay and western blotting revealed that KIFC3 overexpression promoted cell migration and invasion, as well as epithelial-mesenchymal transition (EMT), while KIFC3 knockdown showed the opposite results. Mechanistically, KIFC3 overexpression promoted β-catenin signaling in KYSE450 cells; however, the role of KIFC3 was abolished by XAV-939, the inhibitor of β-catenin signaling.

Conclusion: KIFC3 was overexpressed in ESCC and was associated with poor prognosis. Furthermore, KIFC3 promoted proliferation, migration and invasion of ESCC β-catenin signaling and EMT.