Association of SIRT1 and HMGA1 expression in non-small cell lung cancer

The roles of Silent mating type information regulation 2 homolog 1 (SIRT1) and High mobility group A1 (HMGA1) in human diseases have been extensively studied separately; however, to the best of our knowledge, the current study is the first to report on their interrelationship in lung cancer. The association of SIRT1 and HMGA1 in non-small cell lung cancer (NSCLC) was investigated by evaluating their expression and prognostic significance in 260 patients with NSCLC using immunohistochemistry. SIRT1 and HMGA1 expression were found to be significantly correlated with each other (P<0.001), and both were significantly associated with clinicopathological parameters, including histological type and degree of differentiation. In squamous cell carcinoma (SCC), SIRT1⁺ specimens were significantly associated with shorter overall survival (OS) time (P=0.019). However, in patients with adenocarcinoma (AD), no association was identified between SIRT1 and OS. In addition, HMGA1⁺ specimens were significantly associated with poor differentiation (P=0.028), and were more frequent in SCC than AD (P=0.015). However, HMGA1 was not associated with OS on univariate Cox regression analysis or Kaplan-Meier analysis (both P>0.05). SIRT1/HMGA1 coexpression was significantly associated with male gender (P=0.016), and moderately and poorly differentiated histological grade (P=0.025). The findings indicate that SIRT1 and HMGA1 may have significant effects during tumor progression in NSCLC, particularly in patients with SCC, and are potentially useful as prognostic indicators for patients with NSCLC.