Objective To investigate the expression and clinical significance of stem cells gene Lgr5 in esophageal squamous cell carcinoma(ESCC) tissues and spheroid body-forming cells in ESCC.

Methods The expression level of Lgr5 was assessed in 280 cases of ESCC and 150 cases of normal esophageal squamous epithelia tissues by immunohistochemistry(IHC). Meanwhile, we developed spheroid body-forming cells in ESCC cell line KYSE70. The expression levels of stemness-related genes SOX2, ALDH1A1, NANOG and Lgr5 in spheroid body-forming cells and parental cells were detected via quantitative real-time PCR (qRT-PCR) and Western blot; the detection of Vimentin and N-cadherin, and Transwell experiment were performed to evaluate the invasion and migration abilities in spheroid body-forming cells.

Results The expression level of Lgr5 in ESCC was significantly higher, compared with normal esophageal squamous epithelia (P < 0.05). The high expression of Lgr5 was correlated with the tumor differentiation, lymph node metastasis, invasion, tumor size and AJCC stage (all P < 0.05). Compared with parental cells, the expression levels of SOX2, ALDH1A1 and NANOG were increased in spheroid body-forming cells (all P < 0.05); Lgr5 could up-regulate the expression levels of mRNA and proteins in spheroid body-forming cells (P < 0.05); the migration and invasion abilities of spheroid body-forming cells were increased (all P < 0.05); and the mRNA expression levels of Vimentin and N-cadherin were increased (all P < 0.05).

Conclusion Lgr5 may be a biomarker of recurrence, progression, invasion and migration of ESCC, and the overexpression of Lgr5 in ESCC may identify the ESCC' s stem-like properties, thus Lgr5 may be a gene of regulating stem-like properties in ESCC.