RBP7 (retinol binding protein 7) is an intracellular retinol transport protein 1 that functions primarily in retinoid metabolism and hepatic homeostasis 1. The protein exhibits diverse roles across multiple malignancies. In hepatocellular carcinoma, RBP7 knockdown suppresses cell proliferation and tumor growth in vivo through p38 MAPK pathway activation, with elevated RBP7 expression correlating with worse prognosis 1. In luminal A breast cancer, reduced RBP7 expression associates with tamoxifen resistance; RBP7 transfection restores treatment sensitivity 2. RBP7 functions as a PPARγ target gene in vascular endothelial cells, potentially forming a positive feedback loop with PPARγ for cardioprotective effects 3. In colorectal cancer, RBP7 serves as a tumor microenvironment regulator promoting 5-FU chemotherapy resistance through hypoxia and TNFα/NFκB signaling pathways 4. Recent integrative analyses identify RBP7 in immune-metabolic heterogeneity, where it may upregulate PD-L1 through retinoic acid signaling to drive immunotherapy resistance 5. RBP7 also plays roles in embryonic genome activation during early development 6 and in bladder cancer bone metastasis through EBF1-mediated regulation affecting Th2 cells 7. Pan-cancer analysis demonstrates RBP7's protective effects in breast cancer and uveal melanoma 8, establishing it as a multifunctional prognostic biomarker and potential therapeutic target.