MSR1 in lung squamous cell carcinoma: Prognostic and immunological values in pan-cancer and single-cell analyses and...

Lung squamous cell carcinoma (LUSC) constitutes approximately 40% of lung cancer cases and lacks effective treatments, needing new diagnostic and prognostic tools. Macrophage scavenger receptor 1 (MSR1), as a key receptor in macrophages, is essential in tumor immunity. However, its mechanisms in regulating tumor progression and immunity and its prognostic value in LUSC remain unclear.

MSR1 expression in pan-cancer, particularly LUSC across distinct clinical subgroups, was identified utilizing TIMER, GEPIA, and UALCAN databases. Prognosis analysis of MSR1 in pan-cancer was conducted using SangerBox, GEPIA, PrognoScan and Kaplan-Meier plotter. Using SangerBox and TIMER, association between MSR1 expression and infiltrating immune cells was investigated. MSR1 gene co-expression network and Gene Set Enrichment Analysis (GSEA) in LUSC were constructed using LinkedOmics database. The analysis of single-cell RNA-sequencing (scRNA-seq) was conducted using the GEO database. Association between plasma MSR1 levels and LUSC risk was evaluated in a cohort study with 49,566 UK Biobank participants.

MSR1 was dysregulated in various cancers and lowly expressed in LUSC tissues than in the normal. Higher MSR1 expression was substantially correlated with poor LUSC overall survival. MSR1 positively associated with tumor-associated macrophage (TAM) infiltrations and its markers (CCL2, CD68, IL10). MRS1 closely related to the immune-suppression of macrophages in LUSC. Higher plasma MSR1 levels were positively correlated with increased LUSC risk (HR = 1.33, 95 % CI: 1.07-1.64; P = 0.01).

MSR1 has significant prognostic and immunological values in pan-cancer and represents a possible biomarker for prognosis and diagnosis in LUSC patients.