Prognostic and biological significance of MRPL13 in multiple myeloma: evidence from multi-cohort, single-cell...

Multiple myeloma (MM) is a clonal plasma cell malignancy with high heterogeneity and poor prognosis. Mitochondrial ribosomal protein L13 (MRPL13) has been linked to tumor progression, but its role in MM remains unclear.

We analyzed seven datasets comprising 3,117 patient samples from the Multiple Myeloma Research Foundation (MMRF) CoMMpass study (referred to as the TCGA_MMRF cohort) and the Gene Expression Omnibus (GEO) database to evaluate the association between MRPL13 expression and overall survival (OS). Event-free survival (EFS) analysis was performed in the GSE24080 cohort, and progression-free survival (PFS) analysis was conducted in the GSE136337 cohort. We further analyzed single-cell transcriptomic profiles of 74,986 cells from 24 MM patients to delineate the expression landscape of MRPL13 across distinct cellular populations and functional subclusters and to assess its relationship with the immune microenvironment. We performed functional assays involving siRNA-mediated MRPL13 silencing to investigate its effects on MM cell proliferation and cell-cycle progression in vitro.

High MRPL13 expression was associated with adverse clinical features and poor survival and was identified as a potential independent prognostic factor. Single-cell analysis revealed enrichment in metabolically active malignant plasma cells and an immunosuppressive microenvironment. Silencing MRPL13 inhibited proliferation and induced G0/G1 arrest.

MRPL13 predicts poor prognosis and promotes MM progression through metabolic and immune regulation, supporting its potential as a prognostic biomarker and therapeutic target.