Background and objective: Protein 4.1, a component of cell membrane skeleton, plays a role in maintaining the shape and mechanical stability of erythrocytes. Recent researches showed that protein 4.1 may be associated with the development of tumors. This study was to investigate the expression and significance of membrane skeleton protein 4.1 family members (4.1B, 4.1R, 4.1N and 4.1G) in human non-small cell lung cancer (NSCLC).
Methods: The expression of proteins 4.1B, 4.1R, 4.1N and 4.1G in 147 specimens of NSCLC was detected by EnVision plus immunohistochemistry. The correlations of 4.1B, 4.1R, 4.1N and 4.1G expression to clinicopathologic features of NSCLC were analyzed by Wilcoxon rank sum test and Spearman rank correlation analysis.
Results: The protein levels of 4.1B, 4.1R and 4.1N were significantly lower in lung squamous cell carcinoma tissues than in adjacent normal tissues (P<0.01). The protein levels of 4.1B, 4.1R, 4.1N and 4.1G were significantly lower in lung adenocarcinoma tissues than in adjacent normal tissues (P<0.05). The protein levels of 4.1B and 4.1G were significantly lower in lung squamous cell carcinoma tissues than in lung adenocarcinoma tissues (P<0.05). Protein 4.1G expression in squamous cell carcinoma was positively correlated to tumor cell differentiation (rs=0.386,P<0.01). In adenocarcinoma, the expression of proteins 4.1B, 4.1N and 4.1G were positively correlated to tumor cell differentiation (rs=0.276, P<0.05; rs=0.248,P<0.05; rs=0.268, P <0.05). The expression of protein 4.1s in squamous cell carcinoma and adenocarcinoma were not related to lymph node metastasis, tumor size, patients'age and sex (P>0.05).
Conclusions: Protein 4.1s are weakly expressed in NSCLC tissues than in adjacent normal tissues. The expression of proteins 4.1B, 4.1N and 4.1G are related to tumor cell differentiation.