SMARCA2 deficiency in NSCLC: a clinicopathologic and immunohistochemical analysis of a large series from a single institution

ABSTRACT

BACKGROUND@#SMARCA2 (SWI/SNF Related, Matrix Associated, Actin Dependent Regulator of Chromatin, Subfamily A, Member 2) is an important ATPase catalytic subunit in the switch-sucrose nonfermenting (SWI/SNF) complex. However, its relationship with the pathological features of NSCLC and its prognosis remain unclear.@*METHODS@#We retrospectively reviewed 2390 patients with surgically resected NSCLC, constructed tissue microarrays (TMAs) and performed immunohistochemical assays. We analyzed the correlation of SAMRCA2 with clinicopathological features and evaluated its prognostic value.@*RESULTS@#Among 2390 NSCLC cases, the negative expression ratios of SAMRCA2, SMARCA4, ARID1A, ARID1B and INI1 were 9.3%, 1.8%, 1.2%, 0.4% and 0%, respectively. In NSCLC, male sex, T3 and T4 stage, moderate and poor differentiation, tumor ≥ 2 cm, Ki67 ≥ 15%, SOX-2 negative expression, middle lobe lesion and adenocarcinoma were relative risk factors affecting SMARCA2-negative expression. In lung adenocarcinomas, high-grade nuclei, histological morphology of acinar and papillary, solid and micropapillary and TTF-1-negative expression were relative risk factors affecting SMARCA2-negative expression. Kaplan-Meier survival analysis showed that the OS was shorter in the SMARCA2-negative group. Multivariate survival analysis revealed that SMARCA2-negative expression was an independent factor correlated with a poor prognosis in NSCLC.@*CONCLUSION@#In conclusion, SMARCA2-negative expression is an independent predictor of a poor outcome of NSCLC and is a potential target for NSCLC treatment.