Renal cell carcinoma (RCC) is the most lethal malignancy of the urinary system, with limited treatment options due to drug resistance and the adverse effects associated with current therapies. This review aims to systematically examine the therapeutic potential of flavonoids, which are natural polyphenolic compounds possessing anti-inflammatory, antioxidant, and anticancer properties, in the context of RCC treatment. We summarize the anticancer activities of 26 natural flavonoids, classified into six subclasses, and explore their mechanisms of action, including the inhibition of tumor cell proliferation, migration, and invasion, as well as the induction of apoptosis, autophagy, and ferroptosis. Particular attention is paid to their modulation of key signaling pathways such as the JAK/STAT3, PI3K/Akt/mTOR, and miRNA-related axes, including miR-21/YAP1 and miR-324-3p/GPX4, providing a molecular basis for their anti-RCC activity. We also address several pharmacological challenges that limit the clinical application of flavonoids, including poor bioavailability, metabolic instability, and potential toxicity. Emerging solutions such as novel flavonoid derivatives, advanced drug delivery systems, and rational combination therapy strategies are also discussed. Current clinical evidence, including a phase II trial of flavopiridol in advanced RCC, highlights the potential but also the need for further validation. In conclusion, flavonoids offer a promising approach to improving RCC treatment. Future research should focus on optimizing their therapeutic efficacy and ensuring their safe clinical translation, with the goal of achieving personalized and minimally invasive cancer therapies.

Purpose: This study aims to explore the potential mechanisms of esculin in the treatment of renal cell carcinoma (RCC). Methods: We employed network pharmacology to predict the potential mechanisms and targets of esculin in RCC. Molecular docking techniques were then employed to validate the predicted targets. Additionally, a series of in vitro experiments were conducted to verify the anticancer effects of esculin on RCC cells, including the CCK-8 assay, EdU assay, wound healing assay, apoptosis assay, and Western blot. Results: Network pharmacology and molecular docking results identified GAPDH, TNF, GSK3B, CCND1, MCL1, IL2, and CDK2 as core targets. GO and KEGG analyses suggested that esculin may influence apoptotic processes and target the PI3K/Akt pathway in RCC. Furthermore, the CCK-8 assay demonstrated that esculin inhibited RCC cell viability. Microscopic observations revealed that following esculin treatment, there was an increase in cell crumpling, a reduction in cell density, and an accumulation of floating dead cells. Additionally, with increasing esculin concentrations, the proportion of EdU-positive cells decreased, the wound closure ratio decreased, the proportion of PI-positive cells increased, the expression levels of BAX and cleaved-caspase-3 proteins increased, and the expression level of Bcl2 protein decreased. These findings suggested that esculin inhibits the proliferation and migration of RCC cells while promoting apoptosis. Moreover, esculin was found to target GAPDH and inhibit the PI3K/Akt pathway. Conclusions: This study is the first to elucidate the therapeutic effects of esculin on RCC cells. The results provide evidence supporting the clinical application of esculin and introduce a promising new candidate for RCC treatment.