SUSD2 down-regulation is correlated with the occurrence and development of lung cancer

Abstract Background: Molecularly targeted drugs yielded significant therapeutic advances in oncogene-driven non-small cell lung cancer (NSCLC), but the majority of patients develop acquired resistance. It is important to identify new target sites that mediate lung cancer progression for new targeted drugs development. Methods: SUSD2 expression and methylation in 25 paired lung cancer and adjacent normal lung samples were investigated. In addition, the association between SUSD2 expression and prognosis was evaluated. Results: SUSD2 gene expression was down-regulated in 21 of 25 lung cancer samples. Similarly, SUSD2 protein expression was down-regulated in 20 of 25 lung cancer samples. Furthermore, 7 of 25 lung cancer samples showed a higher methylation compared to adjacent normal lung samples, suggesting that SUSD2 methylation was closely associated with silencing of the gene expression. Except for the pathology type and TNM status (P<0.05), no correlation was observed between SUSD2 expression and other clinicopathological characteristics. Conclusions: Our findings indicated that SUSD2 expression was down-regulated in lung cancer, and SUSD2 methylation might not be involved in SUSD2 gene expression, suggesting that SUSD2 could be a novel candidate gene for future mechanism research of lung cancer.