Full-length spleen tyrosine kinase inhibits the invasion and metastasis of human laryngeal squamous cell carcinoma.

OBJECTIVE

This study aimed to investigate correlation between full-length spleen tyrosine kinase [SYK (L)] expression and clinical characteristics of laryngeal squamous cell carcinoma (LSCC), and explore effects of SYK (L) on invasion and metastasis of LSCC.

METHODS

The human laryngeal cancer Hep-2 cells with low SYK (L) expression were transfected with pIRES2-EGFP-SYK (L) vector and empty vector pIRES2-EGFP to generate Hep-2-SYK (L) cells and Hep-2-neo cells. The cell invasion and migration abilities were determined.

RESULTS

The SYK (L) positive expression rate in LSCC tissues was significantly lower than in vocal cord dysplasia tissues and normal laryngeal tissues (P < 0.05). There was a significant correlation between SYK (L) expression and LSCC T stage, histopathological grade and lymph node metastasis (P < 0.05). mRNA expression of SYK (L) in Hep-2-SYK (L) cells was significantly higher than in Hep-2-neo cells and Hep-2 cells (P < 0.01). The protein expression of SYK (L) in Hep-2-SYK (L) cells was markedly higher than in Hep-2-neo cells and Hep-2 cells (P < 0.01). The number of invasive cells was significantly lower in Hep-2-SYK (L) group than in Hep-2-neo group and Hep-2 group (P < 0.01). The average number of migrating cells in Hep-2-SYK (L) group also markedly reduced as compared to Hep-2-neo group and Hep-2 group (P < 0.01).

CONCLUSIONS

The SYK (L) expression was down-regulated in LSCC, which was closely correlated with cancer growth and lymph node metastasis. SYK (L) up-regulation was able to inhibit the invasion and metastasis of LSCC, therefore suppressing tumor development. Thus, SYK (L) may be a potential target for the LSCC treatment.