Abstract
Lung cancer is the leading cause of cancer-related death worldwide, with an estimated 1.2 million deaths each year. Despite advances in lung cancer treatment, 5-year survival rates are lower than ~15%, which is attributes to diagnosis limitations and current clinical drug resistance. Recently, more evidence has suggested that epigenome dysregulation is associated with the initiation and progress of cancer, and targeting epigenome-related molecules improves cancer symptoms. Interestingly, some groups reported that the level of methylation of histone 3 lysine 4 (H3K4me3) was increased in lung tumors and participated in abnormal transcriptional regulation. However, a mechanistic analysis is not available. In this report, we found that the SET domain containing 1A (SETD1A), the enzyme for H3K4me3, was elevated in lung cancer tissue compared to normal lung tissue. Knockdown of SETD1A in A549 and H1299 cells led to defects in cell proliferation and epithelial-mesenchymal transition (EMT), as evidenced by inhibited WNT and transforming growth factor β (TGFβ) pathways, compared with the control group. Xenograft assays also revealed a decreased tumor growth and EMT in the SETD1A silenced group compared with the control group. Mechanistic analysis suggested that SETD1A might regulate tumor progression via several critical oncogenes, which exhibited enhanced H3K4me3 levels around transcriptional start sites in lung cancer. This study illustrates the important role of SETD1A in lung cancer and provides a potential drug target for treatment.