Mechanisms of sunitinib resistance in renal cell carcinoma and associated opportunities for therapeutics

TRIB3 recruits and stabilizes CARM1 to confer chemoresistance by activating Akt signalling in clear cell renal cancer cells

Sunitinib resistance remains a major obstacle in the treatment of clear cell renal cell carcinoma (ccRCC), yet the underlying mechanisms are poorly defined. Here, we identify a previously unrecognized axis involving Tribbles homolog 3 (TRIB3) and coactivator-associated arginine methyltransferase 1 (CARM1) that drives chemoresistance through modulation of Akt signaling. Mechanistically, TRIB3 directly interacts with CARM1, a pro-survival epigenetic regulator, and inhibits its ubiquitination to stabilize CARM1 protein levels. Elevated CARM1 further exacerbates therapeutic resistance, establishing a feedforward loop that sustains Akt activation. Our findings uncovering a novel TRIB3-CARM1-Akt axis as a central driver of sunitinib resistance. This study provides mechanistic insights into ccRCC chemoresistance and highlights therapeutic targeting of the TRIB3-CARM1 axis as a promising strategy to overcome treatment failure.

Unraveling the mechanisms of tricetin in renal cell carcinoma treatment through network pharmacology and experimental validation

Renal cell carcinoma (RCC), one of the most common types of kidney cancer, represents a major global health concern due to its increasing incidence and high death rates. While conventional treatment modalities have improved patient outcomes, they often face limitations such as drug resistance, severe adverse effects, and limited efficacy in advanced or metastatic cases. These challenges highlight the urgent need for novel therapeutic approaches to enhance RCC management. Tricetin, a natural flavonoid abundant in cereal plants, has shown promising anticancer activity in various malignancies by inhibiting cancer cell proliferation, migration, and invasion. However, the molecular mechanisms underlying Tricetin's effects on RCC remain poorly understood. In this research, we employed network pharmacology to identify key molecular targets of Tricetin in RCC and evaluated its binding affinity to these targets using molecular docking techniques. Bioinformatics analyses were conducted to predict the potential biological pathways involved. Furthermore, in vitro experiments using RCC cell lines (786-O and ACHN) demonstrated that Tricetin suppresses cell proliferation and migration, likely through modulation of the EGFR/PI3K/Akt signaling pathway. Overall, our findings offer new insights into the therapeutic potential of Tricetin and provide a foundation for developing targeted treatment strategies to improve RCC outcomes.

2-Undecanone induces ferroptosis via the STAT3/GPX4 pathway to enhance sensitivity of renal cell carcinoma to sunitinib

The development of resistance significantly reduces the efficacy of targeted therapies, such as sunitinib, in renal cell carcinoma (RCC) patients, emphasizing the need for novel therapeutic agents. Natural products, known for their diverse chemical structures and mechanisms of action, offer promising anti-tumor potential with favorable safety profiles and lower toxicity compared to synthetic drugs. 2-Undecanone, a natural compound extracted from Houttuynia cordata Thunb., has demonstrated anti-tumor effects, but its specific role in RCC treatment remains unclear. In this study, we integrated network pharmacology with in vitro experiments to explore the mechanisms underlying 2-Undecanone's effects on RCC. Our results reveal that 2-Undecanone effectively inhibits RCC cell viability, proliferation, and migration. Mechanistically, we discovered that 2-Undecanone induces ferroptosis in RCC cells by promoting reactive oxygen species (ROS) generation, intracellular Fe2+ accumulation, glutathione (GSH) production, lipid peroxidation, and modulation of the STAT3/GPX4 signaling pathway. Furthermore, 2-Undecanone lowers the IC50 value of sunitinib in RCC cells, enhancing their sensitivity to this targeted therapy. Additionally, 2-Undecanone potentiates sunitinib-induced ferroptosis. In summary, our research reveals that 2-Undecanone enhances the sensitivity of RCC cells to sunitinib through targeting the STAT3/GPX4 pathway, providing new insights into potential therapeutic strategies for RCC.

Long Noncoding RNA E2F1 Messenger RNA Stabilizing Factor (EMS) Promotes Sorafenib Resistance in Renal Cell Carcinoma by Regulating miR-363-3p and Dual-Specificity Phosphatase 10 Expression

Renal cell carcinoma (RCC) is a common kidney disease associated with high mortality. Sorafenib is a protein kinase inhibitor that targets multiple kinases and is used for treating different cancers, including RCC. However, sorafenib resistance in patients with RCC hampers its use. Therefore, elucidating the molecular mechanisms underlying sorafenib resistance in RCC and developing novel therapeutic strategies to overcome drug resistance are vital. In this study, we found that the expression level of the long noncoding RNA (lncRNA) E2F1 messenger RNA stabilizing factor (EMS) was significantly higher in sorafenib-resistant RCC tissues and cell lines than in sorafenib-sensitive RCC tissues and cell lines. lncRNA EMS knockdown improved the sensitivity of sorafenib-resistant RCC cells to sorafenib treatment, as evidenced by decreased cell proliferation and increased apoptosis. Additionally, lncRNA EMS silencing combined with sorafenib treatment markedly inhibited RCC tumor development in vivo. Moreover, it was systematically shown that lncRNA EMS sponged miR-363-3p, whose expression was decreased in sorafenib-resistant RCC. Notably, miR-363-3p negatively regulated the expression of dual-specificity phosphatase 10 (DUSP10) by targeting its 3'-UTR. Furthermore, miR-363-3p overexpression restored sorafenib sensitivity, whereas upregulated DUSP10 expression promoted sorafenib resistance in sorafenib-resistant cell lines. In conclusion, the lncRNA EMS/miR-363-3p/DUSP10 axis regulates sorafenib resistance in RCC, and these molecules are promising biomarkers and therapeutic targets for patients with sorafenib-resistant RCC.

Design, synthesis and biological evaluation of indazole derivatives as VEGFR-2 kinase inhibitors with anti-angiogenic properties

The strategy of inhibiting angiogenesis, specifically by targeting vascular endothelial growth factor receptor 2 (VEGFR-2), has been proven effective in tumor treatment. In this study, we designed several VEGFR-2 kinase inhibitors based on an indazole scaffold. Among them, the most potent compound, 30, inhibits VEGFR-2 (IC50 = 1.24 nM) with subtle selectivity over other kinases. It demonstrates significant inhibitory activity against HUVEC angiogenesis and inhibits cell migration in a dose-dependent manner. Additionally, it exhibits low acute toxicity in mice. In vivo studies, compound 30 demonstrates favorable pharmacokinetic profiles. It suppresses tumor angiogenesis in the zebrafish subintestinal vessel model, indicating that it may be a potential angiogenesis inhibitor for further development.

Hyaluronic acid-functionalized MOFs for combined sunitinib and siRNA therapy in renal cell carcinoma

Sunitinib is a first-line treatment for renal cell carcinoma (RCC), but suffers from drug resistance, causing therapy failure. Therefore, nano-scale delivery systems should be introduced for targeted delivery. Metal-organic frameworks (MOFs) are attractive drug carriers that not only enable multidrug combination therapies but also exert photodynamic effects by incorporating photosensitizers as components. Here, a Zr-based porphyrinic nanoscale MOF, PCN-224, was prepared as the carrier for the co-delivery of sunitinib and the siRNA against vascular endothelial growth factor receptor-2 (VEGFR-2). Drug-loaded PCN-224 is coated with hyaluronic acid (HA) to prevent drug molecular leakage and to exert tumor-targeting effects (CD44 in tumor cells). Photodynamic therapy was conducted under 660 nm laser (50 mW·cm-2, 10 min) irradiation. Compared with St/siVEGFR-2@PCN-224@HA without the HA coating, St/siVEGFR-2@PCN-224@HA significantly suppressed cell viability and promoted cell apoptosis. Laser irradiation further increased the anti-cancer effect of St/siVEGFR-2@PCN-224@HA by generating cytotoxic ROS. H&E staining of major organs revealed no signs of damage, indicating the biosafety of St/siVEGFR-2@PCN-224@HA. The prepared St/siVEGFR-2@PCN-224@HA system enables triple inhibition of tumor growth via a combination of targeted therapy and genetic and photodynamic therapy to enhance the therapeutic effects on RCC.

AUY922 improves sensitivity to sunitinib in clear cell renal cell carcinoma based on network pharmacology and in vitro experiments

Clear Cell Renal Cell Carcinoma (ccRCC), the most prevalent form of renal cell carcinoma (RCC), poses a significant threat to human health due to its rising morbidity and mortality rates. Sunitinib, a pivotal targeted drug for the treatment of ccRCC, presents a significant challenge due to the high susceptibility of ccRCC to resistance. HSP90 inhibitor AUY922 has demonstrated anti-tumor activity in a range of cancer types. However, its efficacy in combination with sunitinib for ccRCC treatment has not been evaluated. In this study, we employed bioinformatics, network pharmacology, and in vitro assays to verify that AUY922 inhibits cell viability, proliferation, and migration of ccRCC cell lines 786-O and ACHN, with IC50s of 91.86 μM for 786-O and 115.5 μM for ACHN. The effect of AUY922 enhancing the inhibitory effect of sunitinib on ccRCC was further confirmed. The CCK-8 assay demonstrated that the IC50 of sunitinib was reduced from 15.10 μM to 11.91 μM for 786-O and from 17.65 μM to 13.66 μM for ACHN, after the combined application of AUY922. The EdU assay and wound healing assay indicated that AUY922 augmented the inhibitory impact of sunitinib on the proliferation and migration of ccRCC cells. Western blot and RT-PCR analyses demonstrated that AUY922 increased the sensitivity of ccRCC cells to sunitinib by targeting the HIF-1α/VEGFA/VEGFR pathway. Our study represents the first investigation into the role and mechanism of AUY922 in enhancing the sensitivity of ccRCC to sunitinib. In conclusion, the findings indicate the potential for AUY922 to enhance the therapeutic efficacy of sunitinib and overcome sunitinib resistance in ccRCC.