Genetic and epigenetic profiling indicates the proximal tubule origin of renal cancers in end-stage renal disease

Genome-wide transcriptome and DNA methylome profiling of acquired cystic disease-associated renal cell carcinoma

Acquired cystic disease (ACD)-associated renal cell carcinoma (RCC) develops uniquely and frequently in patients receiving long-term dialysis for end-stage renal disease (ESRD). In our previous study, the molecular alteration profiles of ACD-associated RCC were partially similar to those of papillary RCC (PRCC). However, the specific profiles of molecular alterations in ACD-associated RCC and their pathogenic mechanisms remain largely unknown. Therefore, we compared genome-wide transcription and DNA methylation profiles of 12 ACD-associated RCC and 26 PRCC samples, which comprised eight ESRD-induced and 18 sporadic (arising in non-dialysis kidney) PRCC samples. RNA-seq and Infinium Methylation EPIC were used to identify the unique genetic and epigenetic profiles in ACD-associated RCC. ACD-associated RCC harboured a unique expression profile from that of PRCC. Its profile was characterised by the upregulation of pathways related to amino acid metabolism. In addition, ACD-associated RCC exhibited a unique DNA methylation profile that was characterised by the hypomethylation of pathways related to amino acid metabolism. This reflected a significant difference between the expression profiles of ACD-associated RCC and PRCC. The present genome-wide transcriptome and DNA methylome profiling revealed that aberrant activation of amino acid metabolism-related pathways, potentially induced by DNA hypomethylation, may be involved in the pathogenesis of ACD-associated RCC.

Epigenetic disruption of adipogenic gene enhancers in dedifferentiated liposarcomas and its therapeutic value

Liposarcoma (LPS) is the most common soft-tissue sarcoma in adults, and well-differentiated liposarcoma (WDLPS) and dedifferentiated liposarcoma (DDLPS) are the most frequent subtypes. These LPSs are considered to develop due to disturbances in the adipogenic differentiation of mesenchymal stem cells. However, the molecular mechanisms underlying the disturbances remain unclear. Here, we aimed to identify the mechanism and explore its therapeutic advantages focusing upon their epigenetic alterations, known to be important in differentiation. First, we conducted a genome-wide DNA methylation analysis using 15 LPSs (6 WDLPSs and 9 DDLPSs) and 6 normal adipose tissues. Unsupervised hierarchical cluster analysis using DNA methylation profiles at enhancers classified the samples into the three histological types, whereas analysis using promoters did not. Principal component analysis revealed that normal adipose tissues and WDLPSs were grouped closely, whereas DDLPSs were scattered. Genomic regions hypermethylated in DDLPSs were enriched for enhancers, especially super-enhancers (13.5% of hypermethylated regions and 7.0% of the whole genome), which were located in the genes involved in adipogenesis, such as PPARG2 and its target genes (FABP4 and PLIN1). In addition, marked decreases in PPARG2 and FABP4 expression were confirmed in DDLPSs. Then, treatment of PPARG2-expressing DDLPS cell lines with 5-aza-2'-deoxycytidine, a DNA demethylating agent, and rosiglitazone, a PPARγ agonist, was shown to induce differentiation with enhanced expression of FABP4. These findings indicate that aberrant DNA methylation of adipogenic gene enhancers plays a crucial role in the development of DDLPS and can be a therapeutic target.

Early separation and parallel clonal selection of dedifferentiated and well-differentiated components in dedifferentiated liposarcoma

Dedifferentiated liposarcoma (DDLPS) comprises a high-grade dedifferentiated (DD) component and a juxtaposed well-differentiated (WD) component. The DD component is believed to originate from the WD component by acquiring additional genomic alterations. In this study, we performed multiregion genome, epigenome, and transcriptome analyses of three patients with DDLPS. In two patients, there were few common genomic alterations across all samples, but many common alterations within DD or WD component samples. Phylogenetic trees predicted from the genomic alterations were consistent with those predicted from DNA methylation patterns. The expression patterns of adipogenesis-related genes differed between DD and WD components and also among patients in connection with their CpG island methylation status. These results indicate that in some patients, WD and DD components are evolutionarily separated at very early stages of tumorigenesis, and are formed through relatively long clonal selection with acquisition of different driver genomic alterations and DNA methylation changes.

Implication of KMT2C and TSC2 variants in the tumorigenesis of acquired cystic disease-associated renal cell carcinomas

In 2020, acquired cystic disease-associated renal cell carcinomas (ACD-RCCs) were reported to harbor KMT2C and TSC2 variants: however, their carcinogenic implication has not yet been reported. This study aimed to explore the variant features of KMT2C and TSC2 in ACD-RCC and their implication in ACD-RCC tumorigenesis. Eleven ACD-RCCs, 10 ACD-RCC-like cysts, and 18 background kidneys were retrieved. The background kidneys consisted of atrophic thyroid follicle-like tubules. They included four with clustered cysts, two with eosinophilic changes, and one each with clear cell changes and sieve-like changes in the renal tubules. First, DNA-targeted sequencing of KMT2C and TSC2 whole exons was performed on eight ACD-RCC samples. Subsequently, a custom DNA panel was designed to include the recurrent KMT2C and TSC2 variants based on the sequencing results. Second, DNA-targeted sequencing was performed on the remaining samples using a custom panel targeting the recurrent variants. Additionally, immunohistochemistry was performed for KMTC, H3K4me1, H3K4me3, TSC2, and GPNMB on the ACD-RCCs. Six of the 11 ACD-RCC cases harbored KMT2C and TSC2 variants, including nine likely pathogenic variants. In contrast to ACD-RCC, 1 of the 9 ACD-RCC-like cysts harbored both variants. Immunohistochemical analysis did not support the loss of function in ACD-RCCs harboring KMT2C and TSC2 variants. KMT2C and TSC2 variant frequencies were higher in ACD-RCC than in other renal cell carcinomas. However, KMT2C and TSC2 are unlikely to be the primary drivers of ACD-RCC development.

Radiogenomics Pilot Study: Association Between Radiomics and Single Nucleotide Polymorphism-Based Microarray Copy Number Variation in Diagnosing Renal Oncocytoma and Chromophobe Renal Cell Carcinoma

RO and ChRCC are kidney tumours with overlapping characteristics, making differentiation between them challenging. The objective of this research is to create a radiogenomics map by correlating radiomic features to molecular phenotypes in ChRCC and RO, using resection as the gold standard. Fourteen patients (6 RO and 8 ChRCC) were included in the prospective study. A total of 1,875 radiomic features were extracted from CT scans, alongside 632 cytobands containing 16,303 genes from the genomic data. Feature selection algorithms applied to the radiomic features resulted in 13 key features. From the genomic data, 24 cytobands highly correlated with histology were selected and cross-correlated with the radiomic features. The analysis identified four radiomic features that were strongly associated with seven genomic features. These findings demonstrate the potential of integrating radiomic and genomic data to enhance the differential diagnosis of RO and ChRCC, paving the way for more precise and non-invasive diagnostic tools in clinical practice.

Single-nucleus sequencing unveils heterogeneity in renal cell carcinomas microenvironment: Insights into pathogenic origins and treatment-responsive cellular subgroups

BACKGROUND

Different individuals with renal cell carcinoma (RCC) exhibit substantial heterogeneity in histomorphology, genetic alterations in the proteome, immune cell infiltration patterns, and clinical behavior.

OBJECTIVES

This study aims to use single-nucleus sequencing on ten samples (four normal, three clear cell renal cell carcinoma (ccRCC), and three chromophobe renal cell carcinoma (chRCC)) to uncover pathogenic origins and prognostic characteristics in patients with RCC.

METHODS

By using two algorithms, inferCNV and k-means, the study explores malignant cells and compares them with the normal group to reveal their origins. Furthermore, we explore the pathogenic factors at the gene level through Summary-data-based Mendelian Randomization and co-localization methods. Based on the relevant malignant markers, a total of 212 machine-learning combinations were compared to develop a prognostic signature with high precision and stability. Finally, the study correlates with clinical data to investigate which cell subtypes may impact patients' prognosis.

RESULTS & CONCLUSION

Two main origin tumor cells were identified: Proximal tubule cell B and Intercalated cell type A, which were highly differentiated in epithelial cells, and three gene loci were determined as potential pathogenic genes. The best malignant signature among the 212 prognostic models demonstrated high predictive power in ccRCC: (AUC: 0.920 (1-year), 0.920 (3-year) and 0.930 (5-year) in the training dataset; 0.756 (1-year), 0.828 (3-year), and 0.832 (5-year) in the testing dataset. In addition, we confirmed that LYVE1+ tissue-resident macrophage and TOX+ CD8 significantly impact the prognosis of ccRCC patients, while monocytes play a crucial role in the prognosis of chRCC patients.

Contemporary review of papillary renal cell carcinoma-current state and future directions

Historically, papillary renal cell carcinoma (PRCC) was divided into two types, type 1 and type 2, based solely on morphology. However, it is apparent that PRCC is far more complex and represents a histological, clinical, and molecular spectrum. There has been a significant evolution in our understanding of PRCC, highlighted by the recognition of new and molecularly defined entities that were previously included in PRCC type 2. This contemporary review addresses the evolving concepts regarding the PRCC, including why it is no longer needed to subtype PRCC, the current molecular landscape, prognostic parameters, and PRCC variants, including biphasic PRCC, papillary renal neoplasm with reverse polarity, and Warthin-like PRCC. Pathologists should also be aware of the potential mimickers of both low-grade and high-grade PRCCs as well as some new and emerging entities that may show papillary growth that should be excluded in the diagnostic workup. The evolving knowledge of PRCC biomarkers, morphologic patterns, and PRCC variants could also have important implications for clinical management. Lastly, the heterogeneity within the PRCC spectrum needs to be further studied, aiming to better stratify PRCC for appropriate clinical management and systemic therapy.

Acquired Cystic Disease-Associated Renal Cell Carcinoma: A Systematic Review and Meta-analysis

Acquired cystic disease-associated renal cell carcinoma (ACD-RCC) is a common subtype of renal cell carcinoma (RCC) in end-stage renal disease (ESRD) patients. The current systematic review and meta-analysis was performed to evaluate the clinicopathological, and genetic characteristics of patients with ACD-RCC. A systematic search on three electronic databases including the Pubmed, Scopus, and Web of Science databases were performed until December 31, 2022. A meta-analysis was performed following the PRISMA 2020 Guidelines. Of 888 identified articles, full-text screening in 69 articles, there were 26 articles analyzed, with a total of 2314 tumors in 2199 patients, including 418 ACD-RCC tumors in 363 patients, 1340 clear cell RCC (ccRCC) tumors, 308 papillary RCC (pRCC) tumors. Most ACD-RCC patients were male (80.2%). All the ACD-RCC patients underwent prior dialysis with 148.2 months of mean dialysis duration. There were 8.7%, 3.4%, and 5.8% tumors at the T3-4 stage, N1 stage, and M1 stage, respectively. The mean overall survival of ACD-RCC patients was 39.6 months (95% CI, 26.6-52.5). Compared to ccRCC and pRCC, ACD-RCC patients had a longer duration of dialysis (MD: 103.5 and 31.77 months, respectively; 95% CI: [75.48; 131.53] and [0.95; 62.58], respectively), and a higher rate of multifocal tumors (MD: 3.46 and 2.45 tumors, respectively; 95% CI [1.71; 6.98] and [1.26; 4.79], respectively). Regarding genetic characteristics, chromosomes 3 and 16 were the 2 most frequent chromosomal aberrations. The missense mutation in KMT2C (25%) and TSC2 (18.75%) were the 2 most common gene mutations in ACD-RCC. In conclusion, the ACD-RCC subtype exhibited several distinct clinicopathological and genetic characteristics compared to others RCC subtypes. Further researchs are needed to assess the survival outcome and the genetic characteristics of this subtype.

Renal cell carcinoma outcomes in end-stage renal disease: A 40-year study from two Japanese institutions

OBJECTIVES

The objective of the study was to analyze the outcomes of patients with renal cell carcinoma (RCC) arising in end-stage renal disease (ESRD) over a 40-year span.

METHODS

We retrospectively evaluated data of patients with ESRD-RCC diagnosed between 1979 and 2020 at two institutions. We assessed changes in stage, surgical approaches, and cancer-specific survival (CSS) following nephrectomy according to era between ESRD-RCC and sporadic RCC. Furthermore, perioperative outcomes in patients with ESRD-RCC were compared between laparoscopic and open surgery.

RESULTS

Patients with ESRD-RCC (n = 549) were diagnosed at an earlier stage (p = 0.0276), and the ratio of laparoscopic nephrectomy was increased (p < 0.0001) according to eras. Since 2000 (i.e., after implementation of laparoscopic nephrectomy), patients with ESRD-RCC (n = 305) had significantly shorter CSS (p = 0.0063) after nephrectomy than sporadic RCC (n = 2732). After adjustment by multivariate analysis and propensity score matching, ESRD status was independently associated with shorter CSS (p = 0.0055 and p = 0.0473, respectively). Improved CSS in sporadic RCC (p < 0.0001), but not ESRD-RCC (p = 0.904), according to era contributed to this difference. Laparoscopic nephrectomy showed favorable outcomes, including shorter surgery time, lower estimated bleeding volumes, transfusion rates, and readmission rates, and shorter postoperative hospitalization than open nephrectomy (p < 0.05).

CONCLUSIONS

Advances in diagnostic and treatment modalities potentially enable early diagnosis and minimally invasive surgery for patients with ESRD-RCC. As ESRD-RCC may not present indolently, careful post-operative monitoring is needed.

Loss of BLK expression as a potential predictor of poor prognosis and immune checkpoint blockade response in NSCLC and contribute to tumor progression

BACKGROUND

Immune checkpoint blockade (ICB) has been proved to have significant anti-tumor effect in the clinical treatment of non-small cell lung cancer (NSCLC). Therefore, biomarkers predicting ICB response can provide better treatment for patients with NSCLC.

METHODS

Differential expression genes (DEGs) were identified by ImmuCellAI database. Copy number alteration (CNA) was analyzed by cBioPortal. The predicted efficiency of 4 genes on cancer immunotherapy was assessed by ROC analysis. The survival value of BLK was analyzed by Kaplan-Meier plotter and Prognoscan analysis. Clinical significance of BLK IHC-TMA score in NSCLC was also explored. The CCK-8 assay, wound healing assay, western blot assay in vitro and subcutaneous xenograft experiments in vivo were used for investigating the functions of BLK. The RNA-sequencing were performed to screen BLK regulated genes and conducted for GO/KEGG enrichment analysis. The transcriptional regulatory factor of BLK promoter region was predicted by ChIP-seq analysis.

RESULTS

39 common DEGs between ICB Response (R) group and No Response (NR) group with NSCLC were identified, in which the CNA frequency of BLK deletion (> 6%) was found. The predicted efficiency of BLK on immunotherapy was performed best in NSCLC (AUC>0.7). Low expression of BLK was related to NSCLC with significantly poor prognosis. BLK overexpression can inhibit growth of NSCLC via activating apoptosis pathway, inhibiting the G2M checkpoint and Glycolysis pathway. The enrichment analysis indicated that BLK regulated genes related to oncogenic potential in NSCLC. Besides, BLK expression was inhibited via H3K27me3 modification in A549 and H1299 cells. BLK mRNA level was negatively correlated with methylation and positively correlated with the tumor purity in NSCLC.

CONCLUSION

Our study provides strong evidence that low expression of BLK may serve as a biomarker for poor prognosis in NSCLC, while response to ICB therapy and contributes to NSCLC tumor progression.

Effects of donor source on transcriptomic profiles of human kidney tissue

Normal human tissue is a critical reference control in biomedical research. However, the type of tissue donor can significantly affect the underlying biology of the samples. We investigated the impact of tissue donor source type by performing transcriptomic analysis on healthy kidney tissue from three donor source types: cadavers, organ donors, and normal-adjacent tissue from surgical resections of clear cell renal cell carcinomas, and we compared the gene expression profiles to those of clear cell renal cell carcinoma samples. Comparisons among the normal samples revealed general similarity, with notable differences in gene expression pathways involving immune system and inflammatory processes, response to extracellular stimuli, ion transport, and metabolism. When compared to tumors, the transcriptomic profiles of the normal adjacent tissue were highly similar to the profiles from cadaveric and organ donor tissue samples, arguing against the presence of a field cancerization effect in clear cell renal cell carcinoma. We conclude that all three normal source types are suitable for reference kidney control samples, but important differences must be noted for particular research areas and tissue banking strategies.

Genomic features of renal cell carcinoma developed during end-stage renal disease and dialysis

Patients with end-stage renal disease (ESRD) or receiving dialysis have a much higher risk for renal cell carcinoma (RCC), but carcinogenic mechanisms and genomic features remain little explored and undefined. This study's goal was to identify the genomic features of ESRD RCC and characterize them for associations with tumor histology and dialysis exposure. In this study, we obtained 33 RCCs, with various histological subtypes, that developed in ESRD patients receiving dialysis and performed whole-genome sequencing and transcriptome analyses. Driver events, copy-number alteration (CNA) analysis and mutational signature profiling were performed using an analysis pipeline that integrated data from germline and somatic SNVs, Indels and structural variants as well as CNAs, while transcriptome data were analyzed for differentially expressed genes and through gene set enrichment analysis. ESRD related clear cell RCCs' driver genes and mutations mirrored those in sporadic ccRCCs. Longer dialysis periods significantly correlated with a rare mutational signature SBS23, whose etiology is unknown, and increased mitochondrial copy number. All acquired cystic disease (ACD)-RCCs, which developed specifically in ESRD patients, showed chromosome 16q amplification. Gene expression analysis suggests similarity between certain ACD-RCCs and papillary RCCs and in TCGA papillary RCCs with chromosome 16 gain identified enrichment for genes related to DNA repair, as well as pathways related to reactive oxygen species, oxidative phosphorylation and targets of Myc. This analysis suggests that ESRD or dialysis could induce types of cellular stress that impact some specific types of genomic damage leading to oncogenesis.

Combination of a synthetic retinoid and a DNA demethylating agent induced differentiation of neuroblastoma through retinoic acid signal reprogramming

BACKGROUND

The CpG island methylator phenotype of neuroblastoma (NBL) is strongly associated with poor prognosis and can be targeted by 5-aza-2'-deoxycytidine (5-aza-dC). Differentiation therapy is a standard maintenance therapy for high-risk NBLs. However, the in vivo effect of tamibarotene, a synthetic retinoic acid, and the efficacy of its combination with 5-aza-dC have not been studied. Here, we conducted a preclinical study to assess the in vivo tamibarotene effect and the combination.

METHODS

Treatment effects were analysed by in vitro cell growth and differentiation state and by in vivo xenograft suppression. Demethylated genes were analysed by DNA methylation microarrays and geneset enrichment.

RESULTS

Tamibarotene monotherapy induced neural extension and upregulation of differentiation markers of NBL cells in vitro, and tumour regression without severe side effects in vivo. 5-Aza-dC monotherapy suppressed tumour growth both in vitro and in vivo, and induced demethylation of genes related to nervous system development and function. Pre-treatment with 5-aza-dC in vitro enhanced upregulation of differentiation markers and genes involved in retinoic acid signaling. Pre-treatment with 5-aza-dC in vivo significantly suppressed tumour growth and reduced the variation in tumour sizes.

CONCLUSIONS

Epigenetic drug-based differentiation therapy using 5-aza-dC and TBT is a promising strategy for refractory NBLs.

Outcome of advanced renal cell carcinoma arising in end-stage renal disease: comparison with sporadic renal cell carcinoma

BACKGROUND

The data regarding oncological outcome in advanced renal cell carcinoma (RCC) arising in end-stage renal disease (ESRD) are limited.

METHODS

Patients diagnosed with advanced RCC on maintenance dialysis therapy (ESRD-RCC) and treated with tyrosine kinase inhibitors (TKIs) were retrospectively evaluated. Progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) after initiation of first-line TKI therapy in ESRD-RCC patients were compared to those in RCC arising in the general population (sporadic RCC).

RESULTS

A total of 36 and 240 patients were diagnosed with advanced ESRD-RCC and sporadic RCC, respectively. PFS and OS were significantly shorter in patients with ESRD-RCC than in those with sporadic RCC (p = 0.0004 and p = 0.0045). After adjusting for histopathological type, MSKCC risk and liver metastasis status, ESRD status (ESRD-RCC vs. sporadic RCC) was not an independent risk factor for PFS or OS (both, p > 0.05). The ORR tended to be lower in patients with ESRD-RCC than in those with sporadic RCC (11% vs. 28%, p = 0.0833). In 34 patients with ESRD-RCC treated with sorafenib, longer duration of dialysis was an independent prognostic factor for shorter OS (hazard ratio 3.21, p = 0.0370).

CONCLUSIONS

Outcome of advanced ESRD-RCC was poorer than that of sporadic RCC, but this finding was affected by other prognostic factors. Nevertheless, the study suggested that advanced ESRD-RCC was not an indolent disease. Additionally, patients with a longer duration of dialysis therapy might require careful monitoring.

Anti-tumor efficacy of human anti-c-met CAR-T cells against papillary renal cell carcinoma in an orthotopic model

Chimeric antigen receptor (CAR)‐T cell therapy has shown salient efficacy in cancer immunotherapy, particularly in the treatment of B cell malignancies. However, the efficacy of CAR‐T for solid tumors remains inadequate. In this study, we displayed that c‐met is an appropriate therapeutic target for papillary renal cell carcinoma (PRCC) using clinical samples, developed an anti‐human c‐met CAR‐T cells, and investigated the anti‐tumor efficacy of the CAR‐T cells using an orthotopic mouse model as pre‐clinical research. Administration of the anti‐c‐met CAR‐T cells induced marked infiltration of the CAR‐T cells into the tumor tissue and unambiguous suppression of tumor growth. Furthermore, in combination with axitinib, the anti‐tumor efficacy of the CAR‐T cells was synergistically augmented. Taken together, our current study demonstrated the potential for clinical application of anti‐c‐met CAR‐T cells in the treatment of patients with PRCC.

Genetic and epigenetic profiling indicates the proximal tubule origin of renal cancers in end-stage renal disease

End‐stage renal disease (ESRD) patients on dialysis therapy have a higher incidence of renal cell carcinomas (RCCs), which consist of 2 major histopathological types: clear‐cell RCCs (ESRD‐ccRCCs) and acquired cystic disease (ACD)‐associated RCCs. However, their genetic and epigenetic alterations are still poorly understood. Here, we investigated somatic mutations, copy number alterations (CNAs), and DNA methylation profiles in 9 ESRD‐ccRCCs and 7 ACD‐associated RCCs to identify their molecular alterations and cellular origins. Targeted sequencing of 409 cancer‐related genes, including VHL, PBRM1, SETD2, BAP1, KDM5C, MET, KMT2C (MLL3), and TP53, showed ESRD‐ccRCCs harbored frequent VHL mutations, while ACD‐associated RCCs did not. CNA analysis showed that ESRD‐ccRCCs had a frequent loss of chromosome 3p while ACD‐associated RCCs had a gain of chromosome 16. Beadarray methylation analysis showed that ESRD‐ccRCCs had methylation profiles similar to those of sporadic ccRCCs, while ACD‐associated RCCs had profiles similar to those of papillary RCCs. Expression analysis of genes whose expression levels are characteristic to individual segments of a nephron showed that ESRD‐ccRCCs and ACD‐associated RCCs had high expression of proximal tubule cell marker genes, while chromophobe RCCs had high expression of distal tubule cell/collecting duct cell marker genes. In conclusion, ESRD‐ccRCCs and ACD‐associated RCCs had mutation and methylation profiles similar to those of sporadic ccRCCs and papillary RCCs, respectively, and these 2 histopathological types of RCCs were indicated to have originated from proximal tubule cells of the nephron.