Adjuvant therapy options in renal cell carcinoma - targeting the metastatic cascade

Centromere protein K enhances the activation of YAP1/TAZ signal cascade to drive the progression of clear cell renal cell carcinoma

Centromere protein K (CENPK) is a newly identified malignancy-related gene that exhibits differential expression in various cancers and plays a crucial role in carcinogenesis. However, it remains uncertain whether CENPK is involved in clear cell renal cell carcinoma (ccRCC). This work aimed to unveil the expression, clinical significance, biological functions, and regulatory mechanisms of CENPK in ccRCC. Through analysis of RNA-seq data obtained from TCGA, a high expression pattern of CENPK was identified in ccRCC, which was found to be associated with pathologic stage, histologic grade, and clinical outcome. The enrichment of CENPK in ccRCC was further verified through the analysis of clinical samples. By conducting cellular functional experiments, we showed an inhibitory effect of CENPK knockdown on the malignant behavior of ccRCC cells. GSEA revealed a close relationship between CENPK and the Hippo-YAP1/TAZ signal cascade. The following experiments demonstrated that the activation of YAP1/TAZ was strongly inhibited by CENPK knockdown, and this change was accompanied by a decrease in the levels of CTGF and CYR61. Blockade of the MST1/2-LATS1/2 axis reversed the suppressive impact of CENPK knockdown on YAP1/TAZ. The tumor-promoting impact observed upon CENPK overexpression was diminished in YAP1 knockout cells. Notably, ccRCC cells with reduced CENPK expression exhibited a diminished capability to form tumors in nude mice. This report highlights the importance of CENPK in ccRCC and sheds new light on the underlying mechanism of this cancer type. Therefore, CENPK has the potential to serve as a viable candidate target for treating ccRCC.

GXYLT2: an emerging therapeutic target and predictive biomarker for anti-PD-1 efficacy in clear cell renal cell carcinoma

There are studies reporting that glucoside xylosyltransferase 2 (GXYLT2) has a role in promoting tumor progression, but its role in clear cell renal cell carcinoma (ccRCC) remains unclear. In this study, RT-qPCR and western blotting were employed to detect the expression level of GXYLT2. RNA interference assays were used to knock down GXYLT2. CCK-8, wound healing assays, clone formation assays, and Transwell assays were utilized to investigate the function of GXYLT2. Bioinformatics analysis was used to explore the tumor microenvironment and potential biological mechanisms. We found that the expression level of GXYLT2 in ccRCC was higher than that in adjacent normal renal tissues. Patients with high GXYLT2 expression have worse clinical outcomes. Knockdown of GXYLT2 inhibits the proliferation, invasion, migration, and clone formation ability of ccRCC cells. Enrichment analysis uncovered that GXYLT2 participates in Wnt, cell cycle, and actin cytoskeleton regulation signaling pathways. After receiving anti-PD-1 therapy, patients with high GXYLT2 expression had longer progression-free survival compared with those with low GXYLT2 expression. In conclusion, GXYLT2 is a novel potential therapeutic target for ccRCC. Meanwhile, GXYLT2 can be used as a novel marker for predicting immunotherapeutic response.

Dynamic Changes in Serum Immunoglobulin G Predict Clinical Response and Prognosis in Metastatic Clear-cell Renal Cell Carcinoma

Background and objective

Systemic treatments involving immunotherapy-tyrosine kinase inhibitor (IO-TKI) combinations and TKI monotherapy have significantly improved outcomes for patients with metastatic clear-cell renal cell carcinoma (mccRCC). However, there are no biomarkers for predicting the efficacy of these treatments. Our aim was to investigate the prognostic and therapeutic significance of serum immunoglobulin G (IgG) in patients with mccRCC patients receiving systemic therapy.

Methods

We included 318 patients with mccRCC who received TKI or IO-TKI therapy. Patients were classified into groups according to whether they had an increase or decrease in serum IgG after systemic treatment. The association between baseline serum IgG and the objective response rate (ORR) was compared between the groups using a t test. The association of the change in serum IgG with progression-free survival (PFS) and overall survival (OS) was evaluated via Cox proportional-hazards regression, and survival curves were generated using the Kaplan-Meier method.

Key findings and limitations

Baseline serum IgG was not significantly associated with ORR (p = 0.055). After 3-mo systemic therapy, 133 patients (42%) exhibited an increase in serum IgG. The group with an IgG increase had significantly poorer median PFS (5.6 vs 16.2 mo; hazard ratio [HR] 3.36, 95% confidence interval [CI] 2.58-4.36; p < 0.001) and OS (26.0 vs 52.2 mo; HR 2.26, 95% CI 1.66-3.08; p < 0.001) than the group with an IgG decrease. Multivariable analysis revealed that an increase in serum IgG after 3-mo systemic therapy was an independent risk factor for both PFS (HR 3.28, 95% CI 2.51-4.30; p < 0.001) and OS (HR 1.94, 95% CI 1.41-2.68; p < 0.001). An increase in serum IgG after 1-mo treatment (n = 160) was also significantly associated with poorer median PFS (7.9 vs 13.7 mo; HR 1.62, 95% CI 1.13-2.32; p = 0.008) and OS (32.6 vs 50.5 mo; HR 1.68, 95% CI 1.09-2.59; p = 0.017).

Conclusions and clinical implications

The change in serum IgG after 3-mo systemic therapy can predict the therapeutic effect and prognosis for patients with mccRCC. This predictive value was observed as early as 1 mo after treatment initiation. Our findings highlight the potential of serum IgG as a predictive biomarker in this setting. Further validation is required in large prospective studies.

Patient summary

We found that for patients with metastatic kidney cancer, changes in the level of an antibody called immunoglobulin G (IgG) in blood during systemic treatment can predict their overall response. Early measurement of IgG could help doctors in personalizing treatment plans and might possibly improve the effectiveness of treatment for these patients.

Molecular imaging of renal cell carcinomas: ready for prime time

The clinical diagnosis of renal cell carcinoma (RCC) is constantly evolving. Diagnostic imaging of RCC relying on enhanced computed tomography (CT) and magnetic resonance imaging (MRI) is commonly used for renal mass characterization and assessment of tumour thrombosis, whereas pathology is the gold standard for establishing diagnosis. However, molecular imaging is rapidly improving the clinical management of RCC, particularly clear-cell RCC. Molecular imaging aids in the non-invasive visualization and characterization of specific biomarkers such as carbonic anhydrase IX and CD70 within the tumours, which help to assess tumour heterogeneity and status. Target-specific molecular imaging of RCCs will substantially improve the diagnostic landscape of RCC and will further facilitate clinical decision-making regarding initial staging and re-staging, monitoring of recurrence and metastasis, patient stratification and selection, and the prediction and evaluation of treatment responses.

IKBKE regulates renal cell carcinoma progression and sunitinib resistance through the RRM2-AKT pathway

Tyrosine kinase inhibitors (TKIs), such as sunitinib, have emerged as promising agents in renal cell carcinoma (RCC) treatment, particularly in patients at advanced/metastatic clinical stages. However, acquired resistance to sunitinib is common following prolonged clinical treatment in RCC. Increasing evidence has demonstrated a strong correlation between inhibitor of nuclear factor kappa B kinase subunit epsilon (IKBKE) and cancer progression as well as drug resistance. Here, we found that IKBKE is upregulated in RCC tissues and sunitinib-resistant RCC cells. High IKBKE expression is positively correlated with advanced clinical staging and a poor prognosis in RCC. Silencing IKBKE downregulates ribonucleotide reductase M2 (RRM2) and induces cell cycle arrest at G2/M phase, suppressing RCC progression and enhancing sunitinib sensitivity to RCC cells. Mechanistically, IKBKE interacts with and phosphorylates RRM2 to activate the AKT signaling pathway to promotes RCC progression and sunitinib resistance. Notably, the IKBKE inhibitor CYT387 restores sunitinib sensitivity in RCC cells by downregulating RRM2 expression. Collectively, these results indicate that inhibition of IKBKE restrains RCC progression and enhances sunitinib sensitivity by downregulating RRM2 through the RRM2-AKT pathway, suggesting that IKBKE may be a potential therapeutic target for RCC.

Prognostic models for predicting oncological outcomes after surgical resection of a nonmetastatic renal cancer: A critical review of current literature

Prognostic models can be valuable for clinicians in counseling and monitoring patients after the surgical resection of nonmetastatic renal cell carcinoma (nmRCC). Over the years, several risk prediction models have been developed, evolving significantly in their ability to predict recurrence and overall survival following surgery. This review comprehensively evaluates and critically appraises current prognostic models for nm-RCC after nephrectomy. The last 2 decades have witnessed a notable increase in the development of various prognostic risk models for RCC, incorporating clinical, pathological, genomic, and molecular factors, primarily using retrospective data. Only a limited number of these models have been developed using prospective data, and their performance has been less effective than expected when applied to broader, real-life patient populations. Recently, artificial intelligence (AI), especially machine learning and deep learning algorithms, has emerged as a significant tool in creating survival prediction models. However, their widespread application remains constrained due to limited external validation, a lack of cost-effectiveness analysis, and unconfirmed clinical utility. Although numerous models that integrate clinical, pathological, and molecular data have been proposed for nm-RCC risk stratification, none have conclusively demonstrated practical effectiveness. As a result, current guidelines do not endorse a specific model. The ongoing development and validation of AI algorithms in RCC risk prediction are crucial areas for future research.

Small molecule inhibitors as adjuvants in cancer immunotherapy: enhancing efficacy and overcoming resistance

Adjuvant therapy is essential in cancer treatment to enhance primary treatment effectiveness, reduce adverse effects, and prevent recurrence. Small molecule inhibitors as adjuvants in cancer immunotherapy aim to harness their immunomodulatory properties to optimize treatment outcomes. By modulating the tumor microenvironment, enhancing immune cell function, and increasing tumor sensitivity to immunotherapy, small molecule inhibitors have the potential to improve patient responses. This review discusses the evolving use of small molecule inhibitors as adjuvants in cancer treatment, highlighting their role in enhancing the efficacy of immunotherapy and the opportunities for advancing cancer therapies in the future.

Deubiquitinase UCHL1 stabilizes KDM4B to augment VEGF signaling and confer bevacizumab resistance in clear cell renal cell carcinoma

BACKGROUND

Bevacizumab resistance poses barriers to targeted therapy in clear cell renal cell carcinoma (ccRCC). Whether there exist epigenetic targets that modulate bevacizumab sensitivity in ccRCC remains indefinite. The focus of this study is to explore the role of UCHL1 in ccRCC.

METHODS

Both in vitro and in vivo experiments were utilized to investigate the roles of UCHL1 in ccRCC. In vivo ubiquitination assays were performed to validate the posttranslational modification of KDM4B by UCHL1. Luciferase reporter and chromatin immunoprecipitation (ChIP) assays were utilized to explore KDM4B/VEGFA epigenetic regulations.

RESULTS

UCHL1 was increased in ccRCC and associated with unfavorable survival outcomes in patients. UCHL1 was required for ccRCC growth and migration. Mechanistically, the wild-type UCHL1, but not C90A mutant, mediated the deubiquitination of KDM4B and thereby stabilized its proteins. KDM4B was up-regulated in ccRCC and potentiated cell growth. UCHL1 depended on KDM4B to augment ccRCC malignancies. Targeting UCHL1 suppressed tumor growth, colony formation, and migration abilities, which could be rescued by KDM4B. Furthermore, KDM4B was directly bound to the promoter region of VEGFA, abolishing repressive H3K9me3 modifications. KDM4B coordinated with HIF2α to activate VEGFA transcriptional levels. UCHL1-KDM4B axis governs VEGFA levels to sustain the angiogenesis phenotypes. Finally, a specific small-molecule inhibitor (6RK73) targeting UCHL1 remarkably inhibited ccRCC progression and further sensitized ccRCC to bevacizumab treatment.

CONCLUSION

Overall, this study defined an epigenetic mechanism of UCHL1/KDM4B in activating VEGF signaling. The UCHL1-KDM4B axis represents a novel target for treating ccRCC and improving the efficacy of anti-angiogenesis therapy.

The role of immunotherapy in urological cancers

Immunotherapy is defined as a therapeutic approach that targets or manipulates the immune system. A deeper understanding of the cellular and molecular composition of the tumour environment, as well as the mechanisms controlling the immune system, has made possible the development and clinical investigation of many innovative cancer therapies. Historically, immunotherapy has played an essential role in treating urologic malignancies, while in the modern era, the development of immune checkpoint inhibitors (ICIs) has been critical to urology. Urothelial carcinoma is a common type of cancer in the genitourinary system, and treatment strategies in this area are constantly evolving. Intravesical and systemic immunotherapeutic agents have begun to be used increasingly frequently in treating urothelial carcinoma. These agents increase the anti-tumour response by affecting the body's defence mechanisms. Immunotherapeutic agents used in urothelial carcinoma include various options such as BCG, interferon, anti-PD-1 (pembrolizumab, nivolumab) and anti-PD-L1 (atezolizumab, avelumab, durvalumab). Renal cell carcinoma (RCC) has been known for many years as a tumour with unique sensitivity to immunotherapies. The recent emergence of ICIs that block PD-1/PD-L1 (pembrolizumab, nivolumab, atezolizumab) or CTLA4 (ipilimumab) signalling pathways has reestablished systemic immunotherapy as central to the treatment of advanced RCC. In light of randomized clinical trials conducted with increasing interest in the application of immunotherapies in the adjuvant setting, combination therapies (nivolumab/ipilimumab, nivolumab/cabozantinib, pembrolizumab/ axitinib, pembrolizumab/lenvantinib) have become the standard first-line treatment of metastatic RCC. Prostate cancer is in the immunologically "cold" tumour category; on the contrary, in recent years, immunotherapeutic agents have come to the fore as an essential area in the treatment of this disease. Especially in the treatment of castration-resistant prostate cancer, immunotherapeutic agents constitute an alternative treatment method besides androgen deprivation therapy and chemotherapy. Ipilimumab, nivolumab, pembrolizumab, atezolizumab, and Sipuleucel T (Vaccine-based) are promising alternative treatment options. Considering ongoing randomized clinical trials, immunotherapeutic agents promise to transform the uro-oncology field significantly. In this review, we aimed to summarize the role of immunotherapy in urothelial, renal and prostate cancer in the light of randomized clinical trials.

Kidney Cancer Research Highlights from ASCO-GU 2024 Meeting

The 2024 American Society of Clinical Oncology (GU ASCO 2024) Genitourinary Cancers Symposium brought together leading cancer specialists from around the world to discuss the latest breakthroughs in treating genitourinary cancers, especially kidney cancer. The focus was on immunotherapy and combination treatments, offering promising new options for patients with advanced and high-risk tumors. The symposium also highlighted advancements in patient care, including a new tool to assess quality of life in people with metastatic kidney cancer.

Beyond boundaries: unraveling innovative approaches to combat bone-metastatic cancers

Evidence demonstrated that bones, liver, and lungs are the most common metastasis sites in some human malignancies, especially in prostate and breast cancers. Bone is the third most frequent target for spreading tumor cells among these organs and tissues. Patients with bone-metastatic cancers face a grim prognosis characterized by short median survival time. Current treatments have proven insufficient, as they can only inhibit metastasis or tumor progression within the bone tissues rather than providing a curative solution. Gaining a more profound comprehension of the interplay between tumor cells and the bone microenvironment (BME) is of utmost importance in tackling this issue. This knowledge will pave the way for developing innovative diagnostic and therapeutic approaches. This review summarizes the mechanisms underlying bone metastasis and discusses the clinical aspects of this pathologic condition. Additionally, it highlights emerging therapeutic interventions aimed at enhancing the quality of life for patients affected by bone-metastatic cancers. By synthesizing current research, this review seeks to shed light on the complexities of bone metastasis and offer insights for future advancements in patient care.

FOXA2 activates HIF2α expression to promote tumor progression and is regulated by the E3 ubiquitin ligase VHL in renal cell carcinoma

Renal cell carcinoma (RCC) is a frequent malignancy of the urinary system with high mortality and morbidity. However, the molecular mechanisms underlying RCC progression are still largely unknown. In this study, we identified FOXA2, a pioneer transcription factor, as a driver oncogene for RCC. We show that FOXA2 was commonly upregulated in human RCC samples and promoted RCC proliferation, as evidenced by assays of cell viability, colony formation, migratory and invasive capabilities, and stemness properties. Mechanistically, we found that FOXA2 promoted RCC cell proliferation by transcriptionally activating HIF2α expression in vitro and in vivo. Furthermore, we found that FOXA2 could interact with VHL (von Hippel‒Lindau), which ubiquitinated FOXA2 and controlled its protein stability in RCC cells. We showed that mutation of lysine at position 264 to arginine in FOXA2 could mostly abrogate its ubiquitination, augment its activation effect on HIF2α expression, and promote RCC proliferation in vitro and RCC progression in vivo. Importantly, elevated expression of FOXA2 in patients with RCC positively correlated with the expression of HIF2α and was associated with shorter overall and disease-free survival. Together, these findings reveal a novel role of FOXA2 in RCC development and provide insights into the underlying molecular mechanisms of FOXA2-driven pathological processes in RCC.

Burden of kidney cancer and attributed risk factors in China from 1990 to 2019

Background

The changing trends and risk-attributed burdens of kidney cancer in China are unknown. Therefore, this study aimed to describe the latest status and trends of kidney cancer burden in China and its associated risk factors.

Methods

The absolute numbers and rates of the incidence, deaths, and disability-adjusted life-years (DALYs) of kidney cancer in China were extracted from the Global Burden of Disease 2019 platform. Overall burden and burden attributed to smoking and high body mass index (BMI) were described. Average annual percent change (AAPC) was calculated to describe trend analyses from 1990 to 2019 using the Joinpoint regression program.

Results

In 2019, 59,827 new cases, 23,954 deaths, and 642,799 DALYs of kidney cancer occurred in China, of which men accounted for 71.1, 70.5, and 72.0%, and the population aged ≥55 years accounted for 58.9, 77.9, and 60.1%, of new cases, deaths, and DALYs, respectively. From 1990 to 2019, the age-standardized incidence rate (per 100,000 person-years) increased from 1.16 in 1990 to 3.21 in 2019, with an AAPC of 3.4% (95% confidence interval [CI]: 3.1-3.8%, p < 0.05); the mortality rate increased from 0.70 to 1.27, with an AAPC of 2.1% (1.5-2.3%, p < 0.05); and the DALY rate increased from 0.70 to 1.27, with an AAPC of 2.1% (1.5-2.3%, p < 0.05). In 2019, the proportions of DALYs attributed to smoking and high BMI were 18.0% and 11.1%, respectively, and the DALY rates attributed to both smoking and high BMI increased from 1990 to 2019, with AAPC of 2.9% (2.6-3.3%, p < 0.05) and 4.8% (4.2-5.4%, p < 0.05), respectively.

Conclusion

The kidney cancer burden in China has continued to grow over the recent three decades, with a severe burden among older adults and men. Therefore, timely preventive interventions for modifiable risk factors are required.