The Molecular Characteristics of Non-Clear Cell Renal Cell Carcinoma: What's the Story Morning Glory?

Papillary Renal Cell Carcinoma: Outcomes for Patients Receiving First-line Immune-based Combinations or Tyrosine Kinase Inhibitors from the ARON-1 Study

BACKGROUND AND OBJECTIVE

Papillary renal cell carcinoma (pRCC) is the most frequent histological subtype of non-clear cell RCC (nccRCC). Owing to the heterogeneity of nccRCC, patients are often excluded from large phase 3 trials focused on clear cell RCC, so treatment options for nccRCC remain limited. Our aim was to investigate the efficacy of first-line treatment with tyrosine kinase inhibitors (TKIs) or immuno-oncology (IO)-based combinations in patients with pRCC.

METHODS

We performed a multicenter retrospective analysis of real-world data collected for patients with advanced pRCC treated in 40 centers in 12 countries as part of the ARON-1 project (NCT05287464). The primary endpoints were overall survival (OS), progression-free survival (PFS), the overall response rate (ORR), and time to second progression (PFS2). OS, PFS, and PFS2 were estimated using the Kaplan-Meier method and results were compared between the treatment groups using a log-rank test. Univariate and multivariable analyses were carried out using Cox proportional-hazard models.

KEY FINDINGS AND LIMITATIONS

We included 200 patients with metastatic pRCC, of whom 73 were treated with IO-based combinations and 127 with TKIs. Median OS was 22.5 mo in the TKI group 28.8 mo in the IO group (p = 0.081). Median PFS was 6.4 mo in the TKI group and 17.4 mo in the IO group (p < 0.001). The ORR was higher in the IO group than in the TKI group (41% vs 27%; p = 0.037).

CONCLUSIONS AND CLINICAL IMPLICATIONS

Our results show that IO-based combinations have superior efficacy outcomes to TKIs for first-line treatment of metastatic pRCC.

PATIENT SUMMARY

The ARON-1 project collects clinical data for patients with kidney cancer treated in multiple centers worldwide to assess outcomes in the real-world setting. We analyzed data for patients with metastatic kidney cancer of a specific subtype to evaluate the efficacy of different first-line treatments. Patients treated with immune-based combinations had better outcomes than patients treated with tyrosine kinase inhibitors.

[2022 WHO classification of renal cell carcinomas: Focus on papillary renal cell carcinoma]

Renal cell carcinomas (RCC) represent a group of heterogeneous tumors whose classification has greatly evolved since 1981. The latest update in 2022 classifies all renal cell carcinomas into six categories according to their morphology or the detection of specific molecular alterations. Molecular disassembly of renal cell carcinomas with papillary features has enabled the identification of new entities characterized by a specific molecular alteration, such as Fumarate Hydratase (FH) deficient RCC, TFE3-rearranged RCC or TFEB-altered RCC. This new classification allows for a more accurate diagnosis but requires a thorough knowledge of the genomic alterations to search for with immunohistochemical or molecular biology techniques. According to the new WHO 2022 classification, papillary renal cell carcinoma (PRC) type 1 or type 2 classification is no longer recommended. A classification based on nucleolar ISUP grade must be preferred: low-grade PRC (ISUP 1-2) or high-grade PRC (ISUP 3-4). The other prognostic factors remain the same: the pTNM stage, lymphovascular invasion, and the presence or absence of dedifferentiated areas referring to sarcomatoid or rhabdoid features. Of note, the presence of necrosis is not currently recognized as a poor prognostic element for this type of carcinoma. The diagnosis of high-grade PRC is from now on a diagnosis of exclusion. It can only be sustained after having ruled out TFE3-rearranged RCC, TFEB-altered RCC, and FH-deficient RCC. For clinicians, the diagnosis of PRC implies suggesting an oncogenetic consultation to screen for an associated genetic tumor syndrome regardless of the patient's age.

Comprehensive analysis of signaling lymphocyte activation molecule family as a prognostic biomarker and correlation with immune infiltration in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a common type of kidney cancer and accounts for 2-3% of all cancer cases. Furthermore, a growing number of immunotherapy approaches are being used in antitumor treatment. Signaling lymphocyte activation molecule family (SLAMF) members have been well studied in several cancers, whereas their roles in ccRCC have not been investigated. The present study comprehensively assessed the molecular mechanisms of SLAMF members in ccRCC, performed using The Cancer Genome Atlas database, with analysis of gene transcription, prognosis, biological function, clinical features, tumor-associated immune cells and the correlation with programmed cell death protein 1/programmed death-ligand 1 immune checkpoints. Simultaneously, the Tumor Immune Dysfunction and Exclusion algorithm was used to predict the efficacy of immune checkpoint blockade (ICB) therapy in patients with high and low SLAMF expression levels. The results demonstrated that all SLAMF members were highly expressed in ccRCC, and patients with high expression levels of SLAMF1, 4, 7 and 8 had a worse prognosis that those with low expression. SLAMF members were not only highly associated with immune activation but also with immunosuppressive agents. The level of immune cell infiltration was associated with the prognosis of patients with ccRCC with high SLAMF expression. Moreover, high ICB response rates were observed in patients with high expression levels of SMALF1 and 4. In summary, SLAMF members may serve as future potential biomarkers for predicting the prognosis of ccRCC and emerge as a novel immunotherapy target.

Renal cell carcinoma histologic subtypes exhibit distinct transcriptional profiles

Molecular profiling of clear cell renal cell carcinoma (ccRCC) tumors of patients in a clinical trial has identified distinct transcriptomic signatures with predictive value, yet data in non-clear cell variants (nccRCC) are lacking. We examined the transcriptional profiles of RCC tumors representing key molecular pathways, from a multi-institutional, real-world patient cohort, including ccRCC and centrally reviewed nccRCC samples. ccRCC had increased angiogenesis signature scores compared with the heterogeneous group of nccRCC tumors, while cell cycle, fatty acid oxidation/AMPK signaling, and fatty acid synthesis/pentose phosphate signature scores were increased in one or more nccRCC subtypes. Among both ccRCC and nccRCC tumors, T effector scores statistically correlated with increased immune cell infiltration and were more commonly associated with immunotherapy-related markers (PD-L1+/TMBhi/MSIhi). In conclusion, this study provides evidence of differential gene transcriptional profiles among ccRCC versus nccRCC tumors, providing insights for optimizing personalized and histology-specific therapeutic strategies for patients with advanced RCC.

Established and emerging biomarkers of immunotherapy in renal cell carcinoma

Immunotherapies, such as immune checkpoint inhibitors, have heralded impressive progress for patient care in renal cell carcinoma (RCC). Despite this success, some patients' disease fails to respond, and other patients experience significant side effects. Thus, development of biomarkers is needed to ensure that patients can be selected to maximize benefit from immunotherapies. Improving clinicians' ability to predict which patients will respond to immunotherapy and which are most at risk of adverse events - namely through clinical biomarkers - is indispensable for patient safety and therapeutic efficacy. Accordingly, an evolving suite of therapeutic biomarkers continues to be investigated. This review discusses biomarkers for immunotherapy in RCC, highlighting current practices and emerging innovations, aiming to contribute to improved outcomes for patients with RCC.

Advances in non-clear cell renal cell carcinoma management: From heterogeneous biology to treatment options

Non-clear cell renal cell carcinoma (nccRCC) makes up nearly one quarter of all RCC subtypes, commonly impacts younger patients, and is often metastatic at presentation. Compared to clear-cell RCC (ccRCC), nccRCC typically has a worse prognosis in the metastatic setting, with overall survival durations that are ~10 months shorter. The nccRCC consists of a wide range of different histological subtypes, the majority of which are composed of papillary, chromophobe, renal medullary carcinoma, translocation RCC, collecting duct carcinoma and unclassified RCC. Most clinical trials have either excluded or only included small numbers of patients with nccRCC; owing to the lack of prospective studies focusing on this population, data on response rates and survival outcomes are lacking. NccRCC treatment is a nascent field with various therapeutic modalities and combinations under investigation, often based on data extrapolated from therapeutic studies in ccRCC. We herein review the use and outcomes of cytotoxic chemotherapy, various combination modalities of tyrosine kinase inhibitors and immune checkpoint inhibitors, and targeted agents. We discuss active ongoing clinical trials for patients with nccRCC and future directions in the treatment of this rare disease. Historically, treatment for nccRCC has been adopted from the standard of care for patients with ccRCC, although these treatments are less effective in the nccRCC population. As we begin to understand the underlying biology of these tumors, clinical trials have been able to slowly accrue and include more patients with various subtypes of nccRCC. There remains much room for improvement in this area of need, but there is hope on the horizon.

Predictive genomic biomarkers of therapeutic effects in renal cell carcinoma

BACKGROUND

In recent years, there have been great improvements in the therapy of renal cell carcinoma. Nevertheless, the therapeutic effect varies significantly from person to person. To discern the effective treatment for different populations, predictive molecular biomarkers in response to target, immunological, and combined therapies are widely studied.

CONCLUSION

This review summarized those studies from three perspectives (SNPs, mutation, and expression level) and listed the relationship between biomarkers and therapeutic effect, highlighting the great potential of predictive molecular biomarkers in metastatic RCC therapy. However, due to a series of reasons, most of these findings require further validation.

Socioeconomic determinants of racial disparities in survival outcomes among patients with renal cell carcinoma

PURPOSE

Racially driven outcomes in cancer are challenging to study. Studies evaluating the impact of race in renal cell carcinoma (RCC) outcomes are inconsistent and unable to disentangle socioeconomic disparities from inherent biological differences. We therefore seek to investigate socioeconomic determinants of racial disparities with respect to overall survival (OS) when comparing Black and White patients with RCC.

METHODS

We queried the National Cancer Database (NCDB) for patients diagnosed with RCC between 2004 and 2017 with complete clinicodemographic data. Patients were examined across various stages (all, cT1aN0M0, and cM1) and subtypes (all, clear cell, or papillary). We performed Cox proportional hazards regression with adjustment for socioeconomic and disease factors.

RESULTS

There were 386,589 patients with RCC, of whom 46,507 (12.0%) were Black. Black patients were generally younger, had more comorbid conditions, less likely to be insured, in a lower income quartile, had lower rates of high school completion, were more likely to have papillary RCC histology, and more likely to be diagnosed at a lower stage of RCC than their white counterparts. By stage, Black patients demonstrated a 16% (any stage), 22.5% (small renal mass [SRM]), and 15% (metastatic) higher risk of mortality than White patients. Survival differences were also evident in histology-specific subanalyses. Socioeconomic factors played a larger role in predicting OS among patients with SRMs than in patients with metastasis.

CONCLUSIONS

Black patients with RCC demonstrate worse survival outcomes compared to White patients across all stages. Socioeconomic disparities between races play a significant role in influencing survival in RCC.

Grain-sized moxibustion at Zusanli (ST36) promotes hepatic autophagy in rats with hyperlipidemia by regulating the ULK1 and TFEB expression through the AMPK/mTOR signaling pathway

Objective

Grain-sized moxibustion is an effective treatment for hyperlipidemia, but how it regulates dyslipidemia and liver lipid deposits still needs to be fully understood. This study explored the molecular biological mechanism of grain-sized moxibustion to regulate hepatic autophagy in hyperlipidemic rats by affecting ULK1 and TFEB through the AMPK/mTOR signaling pathway.

Methods

Thirty male Sprague-Dawley (SD) rats were fed a high-fat diet for eight weeks to induce hyperlipidemia. Hyperlipidemic rats were divided into the HFD group, HFD + Statin group, HFD + CC + Moxi group, and grain-sized moxibustion intervention group (HFD + Moxi group). The control (Blank) group consisted of normal rats without any intervention. Grain-sized moxibustion and drug interventions were initiated eight weeks after high-fat diet induction and continued for ten weeks. Serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL), as well as hepatic triglyceride (TG), were measured after treatment. Hepatic steatosis and the expression of LC3I, LC3II, p62, p-AMPK, AMPK, p-mTOR, mTOR, ULK1, p-ULK1, and TFEB in the liver were analyzed.

Results

Compared with the HFD group, grain-sized moxibustion improved hyperlipidemia and hepatocyte steatosis, increased the LC3, p-AMPK, p-ULK1, and nuclear TFEB expression in the liver, but decreased the p62 and p-mTOR expression.

Conclusion

Grain-sized moxibustion at ST36 acupoints could regulate the blood lipid level of SD rats with hyperlipidemia, increase the expression level of ULK1 and TFEB by activating the AMPK/mTOR signaling pathway in liver tissues, and initiate the transcription of autophagy genes such as LC3.

Prognostic and predictive biomarkers for immunotherapy in advanced renal cell carcinoma

The therapeutic algorithm of renal cell carcinoma has been revolutionized by the approval of immunotherapy agents by regulatory agencies. However, objective and durable responses are still not observed in a large number of patients, and prognostic and predictive biomarkers for immunotherapy response are urgently needed. Prognostic models used in clinical practice are based on clinical and laboratory factors (such as hypercalcaemia, neutrophil count or Karnofsky Performance Status), but, with progress in molecular biology and genome sequencing techniques, new renal cell carcinoma molecular features that might improve disease course and outcomes prediction have been highlighted. An implementation of current models is needed to improve the accuracy of prognosis in the immuno-oncology era. Moreover, several potential biomarkers are currently under evaluation, but effective markers to select patients who might benefit from immunotherapy and to guide therapeutic strategies are still far from validation.

miR‑5590‑3p inhibits the proliferation and metastasis of renal cancer cells by targeting ROCK2 to inhibit proliferation, migration and invasion

The present study aimed to clarify the role of microRNA (miR)-5590-3p in the progression of renal cell carcinoma (RCC) and investigate the underlying mechanisms. The expression levels of miR-5590-3p, Rho-associated protein kinase (ROCK)2 and β-catenin in RCC cells were measured by reverse transcription-quantitative PCR and western blot analysis. Following overexpression of miR-5590-3p and ROCK2 by transfection of miR-5590-3p mimics and GV367-ROCK2, respectively, changes in the proliferation, migration and invasion of RCC cells were determined through colony-formation, wound-healing and Transwell assays, respectively. The direct binding interaction between miR-5590-3p and ROCK2, initially predicted using Targetscan, was validated by a dual-luciferase reporter assay. The results indicated that miR-5590-3p was downregulated in RCC. Overexpression of miR-5590-3p led to downregulation of ROCK2 and β-catenin and inhibited the proliferation, migration and invasion of RCC cells. The dual-luciferase reporter assay confirmed the binding relationship between miR-5590-3p and ROCK2. Of note, overexpression of ROCK2 effectively reversed the regulatory effects of miR-5590-3p on RCC cells. In conclusion, miR-5590-3p inhibits the proliferation, migration and invasion of RCC cells by targeting ROCK2, which is a potential molecular biomarker and therapeutic target for RCC.

Characterizing Tumor Thrombus Arising from Non–Clear Cell Renal Cell Carcinoma

Background

Renal cell carcinoma (RCC) can exhibit a unique vascular tropism that enables tumor thrombus extension into the inferior vena cava (IVC). While most RCC subtypes that form tumor thrombi are of clear cell (cc) histology, non–clear cell (ncc) subtypes can also exhibit this unique growth pattern.

Objective

To characterize clinicopathologic differences and survival outcomes among patients with IVC tumor thrombus arising from ccRCC versus nccRCC.

Design, setting, and participants

Patients diagnosed with IVC tumor thrombus secondary to RCC in our institutional experience from 2003 to 2021 were identified.

Outcome measurements and statistical analysis

Clinicopathologic characteristics were compared by histology. Perioperative and oncologic outcomes including recurrence-free (RFS), overall (OS), and cancer-specific (CSS) survival were assessed using multivariable Cox regression analyses.

Results and limitations

The analyzed cohort included 103 patients (82 ccRCC and 21 nccRCC). There were no significant differences in baseline demographic parameters. Patients with nccRCC were more likely to have regional lymph node involvement (42.9% vs 20.7%, p = 0.037). No differences in perioperative outcomes, IVC resection, or IVC reconstruction were observed between groups. The median follow-up time was 30 mo. The median RFS was 30 (nccRCC) versus 53 (ccRCC) mo (p = 0.1). There was no significant difference in OS or CSS. This study was limited by its small sample size.

Conclusions

Patients with IVC tumor thrombus arising from ccRCC and nccRCC exhibit similar perioperative and oncologic outcomes. While surgical appropriateness was not impacted by histologic subtype, multimodal strategies are needed to improve outcomes for patients with tumor thrombus.

Patient summary

Renal cell carcinoma (RCC) can uniquely invade vasculature and form a tumor thrombus. This study examined the difference in outcomes of patients with tumor thrombus based on RCC subtype (clear cell vs non–clear cell). We found that patients exhibited similar surgical and survival outcomes regardless of RCC type.

Papillary renal cell carcinoma: current and controversial issues

PURPOSE OF THE REVIEW

Papillary renal cell carcinoma (pRCC) is the second most frequent renal cancer subtype and represents 15-20% of all RCC. Classification of pRCC is changing because novel tumour entities have been discovered in the last years. In this review, we summarise recent studies relevant for the understanding of the molecular complexity and the broader differential diagnosis of pRCC.

RECENT FINDINGS

It has been 25 years ago, that pRCC was morphologically subdivided into type 1 and type 2. Recently described tumour entities in the 2022 WHO classification challenged this concept and allow a new view on the molecular background in pRCC. Biphasic hyalinizing psammomatous RCC and papillary renal neoplasm with reversed polarity are emerging tumour entities derived from the new concept of molecularly defined RCC subtypes. Immune checkpoint inhibition and tyrosine kinase inhibitors have been introduced as the new backbone in the first-line treatment of advanced pRCCs. To identify novel targeted treatments for patients with pRCC it is crucial to investigate the specific molecular background of pRCC considering emerging pRCC subtypes.

SUMMARY

In the future, a deeper understanding of the correlation between molecular aberrations and new pRCC subtypes may improve the classification of pRCC patients and could reveal potential predictive biomarkers for each subgroup.

Artificial Intelligence in Kidney Cancer

Artificial intelligence is rapidly expanding into nearly all facets of life, particularly within the field of medicine. The diagnosis, characterization, management, and treatment of kidney cancer is ripe with areas for improvement that may be met with the promises of artificial intelligence. Here, we explore the impact of current research work in artificial intelligence for clinicians caring for patients with renal cancer, with a focus on the perspectives of radiologists, pathologists, and urologists. Promising preliminary results indicate that artificial intelligence may assist in the diagnosis and risk stratification of newly discovered renal masses and help guide the clinical treatment of patients with kidney cancer. However, much of the work in this field is still in its early stages, limited in its broader applicability, and hampered by small datasets, the varied appearance and presentation of kidney cancers, and the intrinsic limitations of the rigidly structured tasks artificial intelligence algorithms are trained to complete. Nonetheless, the continued exploration of artificial intelligence holds promise toward improving the clinical care of patients with kidney cancer.