Preliminary exploration of the potential biological functions and prognosis values of RAB4B in pan-cancer combing with experimental validation in BLCA.

BACKGROUND: Ras-related protein Rab-4B (RAB4B), a small GTPase in the RAS superfamily, is involved in glucose homeostasis, synaptic homeostasis, adaptive immunity, and other processes. RAB4B has also been implicated in tumorigenesis, and its dysregulation has been linked to cancer in multiple organs. However, the potential role of RAB4B in human pan-cancers remains unknown, and whether RAB4B is a predictive biomarker for cancer immunotherapy is yet to be explored.

METHODS: In order to investigate the potential for RAB4B as a therapeutic agent in human pan-cancers and its predictive properties, firstly, relevant data were downloaded from pan-cancers databases. Using the RAB4B expression as a parameter, an analysis was performed. The next step was to investigate how RAB4B relates to overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI). Moreover, we performed an analysis of the relationship between RAB4B and tumor mutational burden (TMB), microsatellite instability (MSI), and tumor microenvironment (TME). Besides, the tumor immune dysfunction and exclusion (TIDE) algorithm was applied to evaluate the efficacy of RAB4B as a potential biomarker for cancer immunotherapy. A final analysis was performed on RAB4B in relation to immune-related genes and pathways.

RESULTS: Results reflected that RAB4B expression was different between tumors and normal tissues. RAB4B not only positively or negatively correlated with survival indicators, but also with clinical characteristics. In addition, RAB4B positively or negatively correlated with TMB, MSI, and TME. The TIDE algorithm revealed that RAB4B was positively or negatively associated with immune checkpoint blockade. The outcome of gene set enrichment analysis (GSEA) suggested that RAB4B positively regulated biological processes and immune cell-related pathways in most cancers.

CONCLUSIONS: According to the research results, we come to the conclusion that RAB4B as a biomarker for tumor immunotherapy, RAB4B facilitates the prediction of pan-cancers prognosis.