Differential expression and subcellular localization of Prohibitin 1 are related to tumorigenesis and progression of non-small cell lung cancer.

Lung cancer remains the leading cause of cancer-related deaths worldwide and non-small cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancer. With a variety of biological functions, Prohibitin1 (PHB1) has been proved tumor-associated. But there are conflicting data regarding the involvement of PHB1 in tumorigenesis and few studies regarding the role of PHB1 in lung cancer. The studies reported herein used a combination of clinical observations and molecular methods to investigate the possible role of PHB1 in NSCLC tissues and cell lines. PHB1 expression was evaluated by RT-PCR, RT-qPCR, Western blotting and immunohistochemistry analysis. Flow cytometric analysis was used to determine the surface expression profiles of PHB1 in lung cell lines. The results showed that PHB1 expression were generally increased in lung cancer tissues when compared with matched noncancerous tissues and closely related with tumor differentiation and lymph node invasion. PHB1 expression levels was also increased in three lung cancer cell lines (SK-MES-1, NCI-H157 and NCI-H292) as compared with BEAS-2B cells. Moreover, there were various subcellular localization of PHB1 in different lung cancer cells and the presence of PHB1 on the surface of lung cancer cells was significantly reduced. In conclusion, PHB1 expression is increased in NSCLC and the up-regulation of PHB1 is associated with clinically aggressive phenotype. The different subcellular localization of PHB1 in NSCLC cells and the loss of the membrane-associated PHB1 probably related to the tumorigenesis and progression of NSCLC and suggests that PHB1 may play different roles in various types of NSCLC.