PRMT5 is a prognostic-related biomarker associated with the tumor immune microenvironment in lung adenocarcinoma

Protein arginine methyltransferase 5 (PRMT5) is an arginine methyltransferase that can methylate both histone and non-histone proteins. It has multiple roles, most notably in the development of cancers, including lung adenocarcinoma (LUAD). However, its prognostic value and immune involvement in LUAD remain to be elucidated.

PRMT5 expression in LUAD was analyzed using TIMER and UALCAN, validated by Western blot and immunohistochemical (IHC) assays. Knockdown experiments assessed its effect on proliferation. GEPIA was used for survival analysis. GSCA examined correlations with copy number variants and methylation. TIMER and TISIDB evaluated immune infiltration and chemokine profiles. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was performed.

TIMER and UALCAN revealed high PRMT5 expression in various tumor types, including LUAD, as confirmed by Western blot and IHC. PRMT5 knockdown significantly reduced cell proliferation, indicating a tumor promoting role. GEPIA analysis identified PRMT5 as a risk factor for poor overall survival in LUAD. PRMT5 expression showed positive association with copy number variants but negative with methylation from GSCA. Further analyses showed that PRMT5 expression was negatively correlated with most immunocytes and chemokines in LUAD from TISIDB. These results indicate PRMT5 contributes significantly to LUAD through immune infiltration. Finally, KEGG analysis showed negative associations of PRMT5 expression with immune and inflammation-related pathways.

These findings demonstrate that PRMT5 has potential as a prognostic biomarker and as an immunomodulatory target in LUAD.