RASSF2 promoter hypermethylation determines malignant and microenvironmental features in lung cancer

Complexity of the microenvironment of lung adenocarcinoma (LUAD) poses significant challenges in its clinical management. Systematic bioinformatic analysis of the Ras-association domain family (RASSF) identified RASSF2 as a potential tumour suppressor in LUAD. This study aims to investigate its clinical significance and functional mechanisms in LUAD. CCK-8, EdU, and colony formation assays were performed to investigate the impact of RASSF2 overexpression on the proliferative capacity of LUAD cells. Transwell and wound healing assays were performed to explore the significance of RASSF2 on LUAD cell migration and invasion. RNA sequencing analysis was conducted on three methylation-positive and three methylation-negative LUAD tissue samples to establish the underlying mechanism of RASSF2 methylation in LUAD. Functional studies indicated that RASSF2 overexpression significantly inhibited the proliferation, migration, and invasion of LUAD cells. Patients with RASSF2 promoter hypermethylation exhibited a significantly shorter overall survival than those without. RNA-seq of three pairs of LUAD tissue samples further demonstrated that RASSF2 methylation is associated with upregulation of the NF-κB signalling pathway and dysregulation of T-cell activation pathways. This study confirmed the tumour-suppressive role of RASSF2 in LUAD and suggests its potential as an immunotherapeutic target, thus providing new insights into LUAD treatment strategies.