Somatic mutations in renal cell carcinomas from Chinese patients revealed by whole exome sequencing

Decoding PTEN regulation in clear cell renal cell carcinoma: Pathway for biomarker discovery and therapeutic insights

Renal cell carcinoma is the most common adult renal solid tumor and the deadliest urological cancer, with clear cell renal cell carcinoma (ccRCC) being the predominant subtype. The PI3K/AKT signaling pathway assumes a central role in ccRCC tumorigenesis, wherein its abnormal activation confers a highly aggressive phenotype, leading to swift resistance against current therapies and distant metastasis. Thus, treatment resistance and disease progression remain a persistent clinical challenge in managing ccRCC effectively. PTEN, an antagonist of the PI3K/AKT signaling axis, emerges as a crucial factor in tumor progression, often experiencing loss or inactivation in ccRCC, thereby contributing to elevated mortality rates in patients. Therefore, understanding the molecular mechanisms underlying PTEN suppression in ccRCC tumors holds promise for the discovery of biomarkers and therapeutic targets, ultimately enhancing patient monitoring and treatment outcomes. The present review aims to summarize these mechanisms, emphasizing their potential prognostic, predictive, and therapeutic value in managing ccRCC.

Frequent gene mutations and the correlations with clinicopathological features in clear cell renal cell carcinoma: preliminary study based on Chinese population and TCGA database

BACKGROUND

Large-scale sequencing plays important roles in revealing the genomic map of ccRCC and predicting prognosis and therapeutic response to targeted drugs. However, the relevant clinical data is still sparse in Chinese population.

METHODS

Fresh tumor specimens were collected from 66 Chinese ccRCC patients, then the genomic RNAs were subjected to whole transcriptome sequencing (WTS). We comprehensively analyzed the frequently mutated genes from our hospital's cohort as well as TCGA-KIRC cohort.

RESULTS

VHL gene is the most frequently mutated gene in ccRCC. In our cohort, BAP1 and PTEN are significantly associated with a higher tumor grade and DNM2 is significantly associated with a lower tumor grade. The mutant type (MT) groups of BAP1 or PTEN, BAP1 or SETD2, BAP1 or TP53, BAP1 or MTOR, BAP1 or FAT1 and BAP1 or AR had a significantly correlation with higher tumor grade in our cohort. Moreover, we identified HMCN1 was a hub mutant gene which was closely related to worse prognosis and may enhance anti-tumor immune responses.

CONCLUSIONS

In this preliminary research, we comprehensively analyzed the frequently mutated genes in the Chinese population and TCGA database, which may bring new insights to the diagnosis and medical treatment of ccRCC.

PD1/PD-L1 blockade in clear cell renal cell carcinoma: mechanistic insights, clinical efficacy, and future perspectives

The advent of PD1/PD-L1 inhibitors has significantly transformed the therapeutic landscape for clear cell renal cell carcinoma (ccRCC). This review provides an in-depth analysis of the biological functions and regulatory mechanisms of PD1 and PD-L1 in ccRCC, emphasizing their role in tumor immune evasion. We comprehensively evaluate the clinical efficacy and safety profiles of PD1/PD-L1 inhibitors, such as Nivolumab and Pembrolizumab, through a critical examination of recent clinical trial data. Furthermore, we discuss the challenges posed by resistance mechanisms to these therapies and potential strategies to overcome them. We also explores the synergistic potential of combination therapies, integrating PD1/PD-L1 inhibitors with other immunotherapies, targeted therapies, and conventional modalities such as chemotherapy and radiotherapy. In addition, we examine emerging predictive biomarkers for response to PD1/PD-L1 blockade and biomarkers indicative of resistance, providing a foundation for personalized therapeutic approaches. Finally, we outline future research directions, highlighting the need for novel therapeutic strategies, deeper mechanistic insights, and the development of individualized treatment regimens. Our work summarizes the latest knowledge and progress in this field, aiming to provide a valuable reference for improving clinical efficacy and guiding future research on the application of PD1/PD-L1 inhibitors in ccRCC.

Potential Role of VHL, PTEN, and BAP1 Mutations in Renal Tumors

The genetic profiling of renal tumors has revealed genomic regions commonly affected by structural changes and a general genetic heterogeneity. The VHL, PTEN, and BAP1 genes are often mutated in renal tumors. The frequency and clinical relevance of these mutations in renal tumors are still being researched. In our study, we investigated VHL, PTEN, and BAP1 genes and the sequencing of 24 samples of patients with renal tumors, revealing that VHL was mutated at a noticeable frequency (25%). Six of the investigated samples showed mutations, and one genetic polymorphism (rs779805) was detected in both heterozygote and homozygote forms. PTEN gene mutation was observed in only one sample, and one specimen showed genetic polymorphism. In the case of the BAP1 gene, all of the samples were wild types. Interestingly, VHL mutation was detected in two female patients diagnosed with AML and in one with oncocytoma. We assume that VHL or PTEN mutations may contribute to the development of human renal cancer. However, the overall mutation rate was low in all specimens investigated, and the development and prognosis of the disease were not exclusively associated with these types of genetic alterations.

A new thinking: deciphering the aberrance and clinical implication of copper-death signatures in clear cell renal cell carcinoma

RATIONALE

Recent research has indicated that cuprotosis, or copper induced cell death, is a novel type of cell death that could be utilized as a new weapon for cancer management. However, the characteristics and implications of such signatures in cancers, especially in clear cell renal cell cancer (ccRCC), remain elusive.

METHODS

Expression, methylation, mutation, clinical information, copy number variation, functional implication, and drug sensitivity data at the pan-cancer level were collected from The Cancer Genome Atlas. An unsupervised clustering algorithm was applied to decipher ccRCC heterogeneity. Immune microenvironment construction, immune therapy response, metabolic pattern, and cancer progression signature between subgroups were also investigated.

RESULTS

Cuprotosis related genes were specifically downregulated in various cancer tissues compared with normal tissues and were correlated with hypermethylation and copy number variation. Cuprotosis scores were also dysregulated in tumor tissues, and we found that such a signature could positively regulate oxidative phosphorylation and Myc and negatively regulate epithelial mesenchymal translation and myogenesis pathways. CPCS1 (cuprotosis scores high) and CPCS2 (cuprotosis scores low) in ccRCC displayed distinctive clinical profiles and biological characteristics; the CPCS2 subtype had a higher clinical stage and a worse prognosis and might positively regulate cornification and epidermal cell differentiation to fuel cancer progression. CPCS2 also displayed a higher tumor mutation burden and low tumor stemness index, while it led to a low ICI therapy response and dysfunctional tumor immunity state. The genome-copy numbers of CPCS2, including arm- gain and arm- loss, were higher than those of CPCS1. The prognostic model constructed based on subgroup biomarkers exerted satisfactory performance in both the training and validation cohorts. In addition, overexpression of the copper death activator DLAT suppressed the malignant ability, including cell migration and proliferation, of renal cell lines in vitro and in vivo. Finally, activation of cuprotosis in tumors could enhance antitumor immunity through dsDNA-cGAS-STING signaling in ccRCC.

CONCLUSION

The activation of cuprotosis might function as a promising approach among multiple cancers. The cuprotosis related signatures could reshape tumor immunity in the ccRCC microenvironment via cGAS-STING signal, thus activating tumor antigen-presenting process. Upregulation of DLAT expression in ccRCC cell lines could reactivate the copper death pattern and be treated as a suitable target for ccRCC.

Molecular characterization of renal cell carcinoma tumors from a phase III anti-angiogenic adjuvant therapy trial

Multigene assays can provide insight into key biological processes and prognostic information to guide development and selection of adjuvant cancer therapy. We report a comprehensive genomic and transcriptomic analysis of tumor samples from 171 patients at high risk for recurrent renal cell carcinoma post nephrectomy from the S-TRAC trial (NCT00375674). We identify gene expression signatures, including STRAC11 (derived from the sunitinib-treated population). The overlap in key elements captured in these gene expression signatures, which include genes representative of the tumor stroma microenvironment, regulatory T cell, and myeloid cells, suggests they are likely to be both prognostic and predictive of the anti-angiogenic effect in the adjuvant setting. These signatures also point to the identification of potential therapeutic targets for development in adjuvant renal cell carcinoma, such as MERTK and TDO2. Finally, our findings suggest that while anti-angiogenic adjuvant therapy might be important, it may not be sufficient to prevent recurrence and that other factors such as immune response and tumor environment may be of greater importance.

Impact of neoadjuvant chemotherapy on somatic mutation status in high-grade serous ovarian carcinoma

BACKGROUND

Patients treated with neoadjuvant chemotherapy (NACT) for advanced high-grade serous ovarian carcinoma (HGSC) have a higher rate and shorter time to platinum-resistant recurrence compared to patients treated with primary cytoreductive surgery (PCS) and adjuvant chemotherapy. The purpose of this study is to determine the impact of NACT on somatic mutation status in platinum-sensitive and resistant HGSC. Patients with advanced HGSC who had a documented response to platinum-based NACT, a banked blood sample, and a banked tumor sample before and after NACT were identified. Whole exome and/or targeted deep sequencing was performed in matched normal and pre/post-NACT tumor samples from 3 platinum-resistant and 2 platinum-sensitive patients to identify somatic non-synonymous mutations at each time point.

RESULTS

When comparing exonic non-synonymous mutations in pre-NACT and post-NACT samples from the same patient, an average of 41% (1-68%) of genes were mutated at both time points. There were no trends detected in the mutational burden following exposure to NACT in platinum-resistant vs. platinum-sensitive cases. The majority of mutated genes were unique to each case. We identified several genes that were commonly mutated in pre-NACT samples specific to platinum-resistant (CSPG4, SLC35G5, TUBA3D) or sensitive (CYP2D6, NUTM1, DNAH5) cases. Four mutated genes emerged exclusively in the platinum-resistant cases (ADGRV1, MUC17, MUC20, PAK2) following NACT.

CONCLUSIONS

Patients with advanced HGSC present with significant intra-tumor heterogeneity. NACT significantly impacts the somatic mutation status irrespective of the time to recurrence. The mutated genes detected in chemo-naive pre-NACT tumor samples from either resistant or sensitive cases could potentially have a role in the prediction of chemotherapy response in patients scheduled to receive NACT; larger studies are required to further validate these genes.

Does the Urinary Proteome Reflect ccRCC Stage and Grade Progression?

Due its ability to provide a global snapshot of kidney physiology, urine has emerged as a highly promising, non-invasive source in the search for new molecular indicators of disease diagnosis, prognosis, and surveillance. In particular, proteomics represents an ideal strategy for the identification of urinary protein markers; thus, a urinomic approach could also represent a powerful tool in the investigation of the most common kidney cancer, which is clear cell Renal Cell Carcinoma (ccRCC). Currently, these tumors are classified after surgical removal using the TNM and nuclear grading systems and prognosis is usually predicted based upon staging. However, the aggressiveness and clinical outcomes of ccRCC remain heterogeneous within each stratified group, highlighting the need for novel molecular indicators that can predict the progression of these tumors. In our study, we explored the association between the urinary proteome and the ccRCC staging and grading classification. The urine proteome of 44 ccRCC patients with lesions of varying severity was analyzed via label-free proteomics. MS data revealed several proteins with altered abundance according to clinicopathological stratification. Specifically, we determined a panel of dysregulated proteins strictly related to stage and grade, suggesting the potential utility of MS-based urinomics as a complementary tool in the staging process of ccRCC.

BRCA1-Associated Protein 1 (BAP-1) as a Prognostic and Predictive Biomarker in Clear Cell Renal Cell Carcinoma: A Systematic Review

BACKGROUND: The gene that encodes BRCA1-associated protein 1 (BAP1) has been reported to be dysregulated in several human cancers such as uveal melanoma, malignant pleural mesothelioma, hepatocellular carcinoma, thymic epithelial tumors, and clear-cell renal cell carcinoma (ccRCC). The gene is located on the human chromosome 3p21.3, encoding a deubiquitinase and acts as a classic two-hit tumor suppressor gene. BAP1 predominantly resides in the nucleus, where it interacts with several chromatin-associated factors, as well as regulates calcium signaling in the cytoplasm. As newer therapies continue to evolve for the management of RCC, it is important to understand the role of BAP1 mutation as a prognostic and predictive biomarker. OBJECTIVE: We aimed to systematically evaluate the role of BAP1 mutations in patients with RCC in terms of its impact on prognosis and its role as a predictive biomarker. METHODS: Following PRISMA guidelines, we performed a systematic literature search using PubMed and Embase through March 2021. Titles and abstracts were screened to identify articles for full-text and then a descriptive review was performed. RESULTS: A total of 490 articles were initially identified. Ultimately 71 articles that met our inclusion criteria published between 2012–2021 were included in the analysis. Data were extracted and organized to reflect the role of BAP1 alterations as a marker of prognosis as well as a marker of response to treatments, such as mTOR inhibitors, VEGF tyrosine kinase inhibitors, and immune checkpoint inhibitors. CONCLUSIONS: Alterations in BAP1 appear to be uniformly associated with poor prognosis in patients with RCC. Knowledge gaps remain with regard to the predictive relevance of BAP1 alterations, especially in the context of immunotherapy. Prospective studies are required to more precisely ascertain the predictive value of BAP1 alterations in RCC.

Comprehensive Genomic Landscape in Chinese Clear Cell Renal Cell Carcinoma Patients

Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cell carcinoma (RCC). The genomic landscape in Chinese ccRCC needs to be elucidated. Herein, we investigated the molecular features of Chinese ccRCC patients. Genomic profiling of DNA was performed through next-generation sequencing (NGS) in Chinese patients with ccRCC between January 2017 and March 2020. Clinical information including age, gender, and tumor histology was collected. Immunohistochemistry (IHC) staining for PD-L1 expression was performed using PD-L1 IHC 22C3 pharmDx assay or Ventana PD-L1 SP263 assay. Data analyses were performed using R 3.6.1. A total of 880 Chinese ccRCC patients who have undergone NGS were included in this study. The most common somatic alterations were detected in VHL (59.7%), PBRM1 (18.0%), SETD2 (12.2%), BAP1 (10.2%), and TP53 (9.4%). Compared with The Cancer Genome Atlas (TCGA) database, a higher mutation frequency of VHL (59.7% vs. 50.0%, p < 0.001) and TP53 (9.4% vs. 3.5%, p < 0.001) and a lower mutation frequency of PBRM1 (18.0% vs. 31.0%, p < 0.001) were found in the Chinese cohort. Of the 460 patients who were evaluated for PD-L1 expression, 139 (30.2%) had positive PD-L1 expression. The median tumor mutational burden (TMB) value was 4.5 muts/Mb (range, 0–46.0). Five (0.7%) patients were identified as microsatellite instability-high (MSI-H). Furthermore, 52 (5.9%) patients were identified to carry pathogenic or likely pathogenic germline mutations in 22 cancer predisposition genes. This is the first large-scale comprehensive genomic analysis for Chinese ccRCC patients, and these results might provide a better understanding of molecular features in Chinese ccRCC patients, which can lead to an improvement in the personalized treatment for these patients.

Clinicopathological and prognostic impact of somatic mutations in Chinese patients with clear cell renal cell carcinoma

Background

The study of the genomic landscape of Chinese clear cell renal cell carcinoma (ccRCC) entered its nascence in recent years, and the clinical relevance of individual genes in Chinese ccRCC has not yet been researched. The study aimed to explore the relationships between somatic mutations and clinical behaviors in Chinese ccRCC.

Methods

Tumor tissue samples were obtained from 105 Chinese patients with ccRCC and deep sequencing targeting 556 cancer genes was performed. Correlation analysis, receiver operator characteristic (ROC) analysis and survival analysis were carried out using SPSS software.

Results

A total of 41 genes were used to investigate the relationship between genes and clinical behaviors. We found that different clinical indices were mutually correlated, and there were 12 genes associated with clinical indices. The Kaplan-Meier curves showed that high Fuhrman grade and metastatic disease at diagnosis were significantly associated with poor prognosis. Mutations in BAP1, PTEN, ERBB2, TP53, CDK8, TSC1, SETD2, or SPEN were significantly associated with poor prognosis, consistent with the results of The Cancer Genome Atlas (TCGA) cohort. Mutation of BTG1 occurred much more frequently in Chinese ccRCC (10.5%) than in the TCGA cohort (0.60%), and it was associated with a better prognosis.

Conclusions

A total of 8 genes (BAP1, PTEN, ERBB2, TP53, CDK8, TSC1, SETD2, and SPEN) were found to be associated with poor prognosis of ccRCC, and a new gene (BTG1) was possibly associated with the good prognosis of Chinese ccRCC.

Inactivation of Epigenetic Regulators due to Mutations in Solid Tumors

Main factors involved in carcinogenesis are associated with somatic mutations in oncogenes and tumor suppressor genes representing changes in the DNA nucleotide sequence. Epigenetic changes, such as aberrant DNA methylation, modifications of histone proteins, and chromatin remodeling, are equally important in the development of human neoplasms. From this perspective, mutations in the genes encoding key participants of epigenetic regulation are of particular interest including enzymes that methylate/demethylate DNA, enzymes that covalently attach or remove regulatory signals from histones, components of nucleosome remodeling multiprotein complexes, auxiliary proteins and cofactors of the above-mentioned molecules. This review describes both germline and somatic mutations in the key epigenetic regulators with emphasis on the latter ones in the solid human tumors, as well as considers functional consequences of these mutations on the cellular level. In addition, clinical associations of the somatic mutations in epigenetic regulators are presented, as well as DNA diagnostics of hereditary cancer syndromes due to germline mutations in the SMARC proteins and chemotherapy drugs directly affecting the altered epigenetic mechanisms for treatment of patients with solid neoplasms. The review is intended for a wide range of molecular biologists, geneticists, oncologists, and associated specialists.

The cell-surface anchored serine protease TMPRSS13 promotes breast cancer progression and resistance to chemotherapy

Breast cancer progression is accompanied by increased expression of extracellular and cell-surface proteases capable of degrading the extracellular matrix as well as cleaving and activating downstream targets. The type II transmembrane serine proteases (TTSPs) are a family of cell-surface proteases that play critical roles in numerous types of cancers. Therefore, the aim of this study was to identify novel and uncharacterized TTSPs with differential expression in breast cancer and to determine their potential roles in progression. Systematic in silico data analysis followed by immunohistochemical validation identified increased expression of the TTSP family member, TMPRSS13 (transmembrane protease, serine 13), in invasive ductal carcinoma patient tissue samples compared to normal breast tissue. To test whether loss of TMPRSS13 impacts tumor progression, TMPRSS13 was genetically ablated in the oncogene-induced transgenic MMTV-PymT tumor model. TMPRSS13 deficiency resulted in a significant decrease in overall tumor burden and growth rate, as well as a delayed formation of detectable mammary tumors, thus suggesting a causal relationship between TMPRSS13 expression and the progression of breast cancer. Complementary studies using human breast cancer cell culture models revealed that siRNA-mediated silencing of TMPRSS13 expression decreases proliferation, induces apoptosis, and attenuates invasion. Importantly, targeting TMPRSS13 expression renders aggressive triple-negative breast cancer cell lines highly responsive to chemotherapy. At the molecular level, knockdown of TMPRSS13 in breast cancer cells led to increased protein levels of the tumor-suppressive protease prostasin. TMPRSS13/prostasin co-immunoprecipitation and prostasin zymogen activation experiments identified prostasin as a potential novel target for TMPRSS13. Regulation of prostasin levels may be a mechanism that contributes to the pro-oncogenic properties of TMPRSS13 in breast cancer. TMPRSS13 represents a novel candidate for targeted therapy in combination with standard of care chemotherapy agents in patients with hormone receptor-negative breast cancer or in patients with tumors refractory to endocrine therapy.

Cell Polarity Protein Pals1-Associated Tight Junction Expression Is a Favorable Prognostic Marker in Clear Cell Renal Cell Carcinoma

Introduction: The Pals1-associated tight junction (PATJ) is a Crumbs (CRB) complex component that regulates epithelial cell apico-basal polarity and directional migration. This study assessed PATJ expression in clear cell renal cell carcinoma (ccRCC) vs. normal tissues and associated with ccRCC progression and prognosis. Methods: The effects of PATJ knockdown were investigated on regulation of normal kidney epithelial cell viability and protein expression in vitro. The PATJ mRNA data in ccRCC were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases and analyzed with UALCAN, LinkedOmics, Kaplan-Meier Plotter, GEPIA, and SurvExpress tools. Immunohistochemistry was performed for PATJ in tissue microarray sections (n = 150 ccRCC and 30 normal renal specimens). Normal human kidney tubular epithelial cell (HKC) cells were transfected with PATJ and negative control siRNA for cell viability CCK-8 assay, flow cytometry, and western blots. Results: The data showed that PATJ mRNA and protein were downregulated in ccRCC tissues and cell lines. Downregulation of PATJ mRNA was associated with male patients, advanced tumor stages, grades, and ccB subtypes as well as poorer overall and disease-free survival of patients. Furthermore, PATJ protein was also significantly downregulated in ccRCC tissues and associated with advanced tumor pathologic, TNM stages and poorer overall. In vitro, knockdown of PATJ expression promoted HKC proliferation and the activation of mitogen-activated protein kinases (MAPK) pathway proteins. Conclusions: This study revealed that a decrease of PATJ in ccRCC, which was associated with male patients, advanced tumor, and poorer survival, suggesting that PATJ may be a useful prognostic biomarker and therapeutic target for ccRCC.

Exceptional response to nivolumab of a heavily pre-treated patient with metastatic renal-cell cancer: from a case report to molecular investigation and future perspectives

Immunotherapy may result in long-lasting exceptional clinical responses, the molecular background of which is inadequately understood. Here, we present the case of a 63-year-old patient with a past medical history of renal cancer who relapsed many years later. Several treatment lines were administered prior to immunotherapy, which was administered in the ninth line, achieving complete remission which had lasted for more than 3 years. Genomic alterations, tumor mutational burden (TMB), and microsatellite instability as well as PD-L1, MLH1, MSH2, MSH6, PMS2, CD3, CD8, CD20, CD138, CD1a, and FoxP3 expression were assessed in primary and metastatic tumors. Primary and metastatic tumors were microsatellite stable with high TMB, while somatic mutations in MLH1 and TP53 genes were detected, respectively. Although the primary tumor was negative for PD-L1 expression, the lung metastasis was positive. Interestingly, metastasis displayed a dramatically increased infiltration by CD1a-positive dendritic cells in addition to increased CD3+ and CD8+ cytotoxic T cells. Increased infiltration of the metastatic tumor by CD1a+ antigen presenting cells warrants further investigation to assess its potential predictive value.

TUBB3 Is Associated with High-Grade Histology, Poor Prognosis, p53 Expression, and Cancer Stem Cell Markers in Clear Cell Renal Cell Carcinoma

BACKGROUND

βIII-Tubulin, encoded by the TUBB3 gene, is a microtubule protein. Several studies have shown that overexpression of TUBB3 is linked to poor prognosis and is involved in taxane resistance in some cancers.

OBJECTIVE

The aim of this study was to analyze the expression and function of TUBB3 in clear cell renal cell carcinoma (ccRCC).

METHODS

The expression of TUBB3 was determined using immuno-histochemistry in ccRCC specimens. The effects of TUBB3 knockdown on cell growth and invasion were evaluated in RCC cell lines. We analyzed the interaction between TUBB3, p53, cancer stem cell markers, and PD-L1.

RESULTS

In 137 cases of ccRCC, immunohistochemistry showed that 28 (20%) of the ccRCC cases were positive for TUBB3. High TUBB3 expression was significantly correlated with high nuclear grade, high T stage, and N stage. A Kaplan-Meier analysis showed that high expression of TUBB3 was associated with poor overall survival after nephrectomy. In silico analysis also showed that high TUBB3 expression was correlated with overall survival. Knockdown of TUBB3 suppressed cell growth and invasion in 786-O and Caki-1 cells. High TUBB3 expression was associated with CD44, CD133, PD-L1, and p53 in ccRCC. We generated p53 knockout cells using the CRISPR-Cas9 system. Western blotting revealed that p53 knockout upregulated the expression of TUBB3.

CONCLUSION

These results suggest that TUBB3 may play an oncogenic role and could be a potential therapeutic target in ccRCC.

Genomic Alterations of Renal Cell Carcinoma and Clinical Implications in the Chinese Population

Background

The aim of this study was to investigate the genomic alterations of renal cell carcinoma (RCC) in Chinese patients and to evaluate the correlations between significantly mutated genes and tumor mutation burden (TMB) levels in RCC.

Material/Methods

Two batch of specimens were collected from patients with RCC. Cohort 1 enrolled 17 RCC patients. Specimens and clinicopathological data were collected and the duration of disease-free survival were evaluated with a follow-up from 2 weeks to longer than 1 year. Cohort 2 collected 70 clear cell RCC (ccRCC) tissues and blood specimens. Next-generation sequencing were used to detect the genomic variations in those specimens in both cohorts and TMB in cohort 2. Clinicopathological features of the 2 cohorts were collected and the χ² test or Fisher’s exact test was used for categorical variables stratified by TMB values.

Results

Our present study demonstrated that the top 3 most frequent aberrated genes in Chinese ccRCC patients were ABCB1, UGT1A1, and VHL, with percentages of 50.00%, 42.86%, and 34.52% respectively. And only 1 gene, which was ABCB1, showed statistically significant difference (P=0.047) stratified by TMB levels. In addition, 6 oncogenic pathways were involved in ccRCC cases in the 2 cohorts. Only 5 out of the 8 most common altered genes of RCC from COSMIC or TCGA databases were detected in our study.

Conclusions

The genomic alterations of Chinese RCC patients were different from that in TCGA and COSMIC. No significant genomic alterations were found correlating to TMB levels in ccRCC. Non-silent mutation of VHL may be a predictor for the outcome of ccRCC treated with axitinib.