CLEC3B Inhibits Invasion and Metastasis of Esophageal Squamous Cell Carcinoma by Regulating Cellular Inflammation, DNA Damage and Cell Cycle

Abstract

Background: Many malignancies are associated with C-Type Lectin Domain Family 3 Member B (CLEC3B), but the mechanism by which it affects esophageal squamous cell carcinoma (ESCC) cells is unclear. This study will investigate the changes of CLEC3 on invasion, migration, and cell cycle of ESCC. The effect of CLEC3 on the growth of Besophageal squamous cell carcinoma was also verified through transplanted tumors. Methods: Differences in CLEC3B expression were explored by immunohistochemistry and RT-qPCR (real-time quantitative polymerase chain reaction). Effects of overexpression of CLEC3B on ESCC cell behavior were observed in vitro. ESCC cells were divided into ov-NC (negative control) and ov-CLEC3B groups. The effect of CLEC3B on the proliferative activity and invasive metastasis of ESCC cells was investigated. The transcriptome of human esophageal squamous carcinoma cells-30 (KYSE-30) was sequenced. The molecular mechanism of CLEC3B action on ESCC cells was verified by ELISA (enzyme linked immunosorbent assay), immunofluorescence staining, flow cytometry and western blot. The effect of CLEC3B overexpression on ESCC growth was measured in vitro. BALB/c nude mice were injected with adenovirus in subcutaneous tumor xenograft experiments. The size and weight of xenograft tumors were measured. Immunohistochemistry was performed to detect ki67. CLEC3B expression was detected by RT-qPCR and Western blot. Results: CLEC3B expression was decreased in ESCC tissues and cells compared to normal tissues and cells. Esophageal cancer cells overexpressing CLEC3B showed reduced proliferative activity, metastasis and invasive ability. Overexpression of CLEC3B increased the level of inflammation in esophageal cancer cells, exacerbated the degree of DNA damage, resulting in cell cycle halt in the G1 phase. Possible pathways through which CLEC3B exerts these effects include the MAPK (Mitogen-activated protein kinases) pathway, NOD-like receptors pathway and NF-κB (nuclear factor kappa-B) pathway. Overexpression of CLEC3B inhibited the proliferation of subcutaneous xenograft tumors and increased the expression of CLEC3B. Conclusions: CLEC3B suppresses esophageal squamous cell carcinoma cell growth, invasion, and metastasis by raising inflammation, increasing cellular DNA damage, and triggering cell cycle arrest.