The Function of Dendritic Cell-Associated lncRNA in the Stomach Adenocarcinoma Immune Microenvironment and Construction of a Prognostic Model

This study investigated the role of dendritic cell (DC)-associated long non-coding RNAs (lncRNAs) within the immune microenvironment of stomach adenocarcinoma (STAD) and created a prognostic model. By analyzing GSE167297 single-cell data through the TISCH2 platform, DC-related genes (DCRGs) were tagged, and 421 distinctively expressed DC-related lncRNAs were screened from the TCGA-STAD dataset. Using Cox regression and least absolute shrinkage and selection operator (LASSO) algorithms, 6 lncRNAs (AC023590.1, LINC00665, AC090337.2, AC109782.1, AP000695.2, AP005262.1) were selected from 25 prognosis- connected lncRNAs to build a risk score pattern. The pattern exhibited excellent predictive capability within the training set, verification set, and overall cohort (5-year ROC AUC = 0.961) and was independently associated with age, grade, and stage. Immune analysis revealed that conventional DCs (cDCs) were positively correlated and plasmacytoid DCs (pDCs) oppositely linked with the risk score, with the high- score patients showing sensitivity to Dasatinib. According to the score, three molecular categories (C1-C3) were delineated, with C1 exhibiting the worst prognosis. The subtypes displayed significant disparities in immune checkpoint expression and drug responsiveness (e.g., 5-Fluorouracil, Cytarabine). This model unveils the immune heterogeneity of STAD and provides biomarkers for precision therapy.