Roles of MTA1 gene in laryngeal squamous cell carcinoma invasion and metastasis

Abstract

Objective To Study the correlation between the expression of metastasis associated gene 1 (MTA1) and clinical characteristics in laryngeal squamous cell carcinoma (LSCC). Methods Immunohistochemistry staining and reverse transcription-polymerase chain reaction (RT-PCR) were adopted to detect the expression of MTA1 in the tissues of LSCC and the correlation between the expression of MTA1 and T stage, lymph node metastasis was analyzed. The siRNA against MTA1, a sequence non-specific to any known gene (NiRNA) was chemically synthesized and transfected into HEP-2 cells, and empty vector was transfected into cells as controls. The MTA1 protein and mRNA levels in the transfected cells were assayed by RT-PCR and Western blotting respectively and cellular biological characteristics were observed by wound healing assay, invasion assay and adhesion assay. Results The positive expression rate of MTA1 was 67.5% in LSCC, which was higher significantly than that in normal and dysphasia tissues (P＜0.05 ). The levels of MTA1 mRNA in ISCC, dysphasia and normal tissues were respectively 1.174± 0.069, 0.739±0.104 and 0.439±0.029, with the difference being statistically significant. The expression of MTA1 was correlated with the clinical stages, histopathology grade and lymphatic metastasis.The levels of MTA1 mRNA in the cells transfected with siRNA against MTA1, NiRNA and empty vector were 0.400±0.067,0.984±0.092 and 0.964±0.123, and those of MTA1 protein were 0.406±0.021,1.080±0.081 and 1.040±0.021 respectively. The siRNA against MTA1 could efficiently inhibit MTA1 gene expression, and cell invasion, adhesion and movement were decreased as compared with the other groups. Conclusion The expression of the MTA1 gene is closely correlated with tumor growth and lymph node metastasis. The down-regulated of the MTA1 expression can decrease cell invasion, adhesion and movement. Key words: Laryngeal neoplasms; Carcinoma; squamous cell; MTA1