Objective: To investigate the expression of human myozenin 2 (MYOZ2) in cancer tissues and its effect on the prognosis of patients with gastric cancer.
Patients and methods: Gastric cancer tissue and adjacent normal tissue specimens were obtained from a total of 258 patients together with complete clinicopathological data. Those patients were treated in Harbin Medical University Cancer Hospital from March 2007 to March 2012. Quantitative Real Time-Polymerase Chain Reaction (RT-PCR) was used to detect the expression of MYOZ2 messenger RNA (mRNA) in gastric cancer tissues and normal gastric tissues, and correlations between the expression level of MYOZ2 in gastric cancer tissues and the clinicopathological parameters of patients were analyzed. MYOZ2 protein expression levels in different gastric cancer cells were detected by Western blotting; transwell chamber assay was used to detect the effect of MYOZ2 expression on the in-vitro migration and invasion abilities of gastric cancer cells; 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was applied to examine the in-vitro proliferation and growth abilities of gastric cancer cells.
Results: The expression level of MYOZ2 mRNA in gastric cancer tissues was significantly higher than that in cancer-adjacent tissues in 258 cases (p<0.05). Western blotting results showed that the expression level of MYOZ2 protein in gastric cancer tissues was significantly increased compared with that in the corresponding adjacent healthy tissues (p<0.05). In-vitro growth, migration and invasion abilities of MYOZ2 positive gastric cancer cells were significantly higher than those of normal tissue cells. Univariate analysis showed that the high expression level of MYOZ2 in gastric cancer tissues was closely related to tumor size, lymph node metastasis, and pathological tumor-node-metastasis (pTNM) staging (p<0.05), but not associated with gender, age, differentiation degree, and tumor location (p>0.05). The 1-, 3- and 5-year survival rates of patients with low expression level of MYOZ2 (n=130) were higher than those of patients with high expression level of MYOZ2 (n=128). Multivariate analysis revealed that the expression level of MYOZ2 (p=0.000), lymph node metastasis (p=0.002), and pTNM staging (p=0.015) were independent risk factors influencing the prognosis of gastric cancer.
Conclusions: Our results showed that the expression level of MYOZ2 may play an important role in the occurrence and development of gastric cancer, and can also provide references for the clinical diagnosis and treatment of gastric cancer.