Abstract 7020: Prognostic implications of microRNA 181a 2 3p expression in association with tumor budding in patients with stage III lung squamous cell carcinoma

Abstract Introduction: Tumor budding (Bd) has been known as an independent prognostic factor in various malignancies. MicroRNA (miRNA) are known to play an important role in regulating Bd. However, understanding the relationship between Bd and miRNA in Lung Squamous cell carcinoma (LUSC) remains limited. Methods: 115 LUSC patients who underwent curative resection were included in the discovery cohort. Bd was verified through immunohistochemical (IHC) stain. Bd was classified according to a three tier system: Bd1 with 0-4 buds, Bd2 with 5-9 buds, and Bd3 with 10 or more buds. MiRNA expression profiles were analyzed through RNA sequencing. Differences in survival outcomes for miRNA, as identified in the discovery cohort, were confirmed using LUSC data of The Cancer Genome Atlas (TCGA) as a validation cohort. Results: The relationship between Bd2 and the prolongation of recurrence-free survival (RFS) was statistically significant (p=0.0113), whereas Bd1 was correlated with Overall Survival (OS) (p=0.0468). Multivariate analysis indicated that both a high T stage (HR: 5.211, 95% CI: 1.168-23.250, p = 0.031; and HR: 5.107, 95% CI: 1.447-18.030, p < 0.011) and Bd3 (HR: 3.683, 95% CI: 1.370-9.900, p = 0.010; and HR: 1.600, 95% CI: 0.800-3.201, p = 0.018) are independently significant poor prognostic factors for both RFS and OS. MiRNA-181a-2-3p was identified through Differentially Expressed miRNA (DER) analysis. A higher expression of miRNA-181a-2-3p in stage III LUSC of the TCGA dataset was associated with OS (p=0.0463). Conclusions: Our study demonstrates that the miRNA 181a 2 3p expression is associated with improved OS. This association may be attributed to its inhibitory effect on Bd in advanced stages of LUSC. Citation Format: Eunhyo Lee, Seoree Kim, Jeana Kim, Minho Lee, Yoonho Ko, Sang Hoon Chun. Prognostic implications of microRNA 181a 2 3p expression in association with tumor budding in patients with stage III lung squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7020.