Solute carrier-related signature for assessing prognosis and immunity in patients with clear-cell renal cell carcinoma

Background:Clear-cell renal cell carcinoma(ccRCC)is the most common malignant kidney cancer.However,the tumor microenvironment and crosstalk involved in metabolic reprogramming in ccRCC are not well-understood.Methods:We used The Cancer Genome Atlas to obtain ccRCC transcriptome data and clinical information.The EMTAB-1980 cohort was used for external validation.The GENECARDS database contains the first 100 solute carrier(SLC)-related genes.The predictive value of SLC-related genes for ccRCC prognosis and treatment was assessed using univariate Cox regression analysis.An SLC-related predictive signature was developed through Lasso regression analysis and used to determine the risk profiles of patients with ccRCC.Patients in each cohort were separated into high-and low-risk groups based on their risk scores.The clinical importance of the signature was assessed through survival,immune microenvironment,drug sensitivity,and nomogram analyses using R software.Results:SLC25A23,SLC25A42,SLC5A1,SLC3A1,SLC25A37,SLC5A6,SLCO5A1,and SCP2 comprised the signatures of the eight SLCrelated genes.Patients with ccRCC were separated into high-and low-risk groups based on the risk value in the training and validation cohorts;the high-risk group had a significantly worse prognosis(p<0.001).The risk score was an independent predictive indicator of ccRCC in the two cohorts according to univariate and multivariate Cox regression(p<0.05).Analysis of the immune microenvironment showed that immune cell infiltration and immune checkpoint gene expression differed between the two groups(p<0.05).Drug sensitivity analysis showed that compared to the low-risk group,the high-risk group was more sensitive to sunitinib,nilotinib,JNK-inhibitor-VIII,dasatinib,bosutinib,and bortezomib(p<0.001).Survival analysis and receiver operating characteristic curves were validated using the E-MTAB-1980 cohort.Conclusions:SLC-related genes have predictive relevance in ccRCC and play roles in the immunological milieu.Our results provide insight into metabolic reprogramming in ccRCC and identify promising treatment targets for ccRCC.

Identification of Prognostic Related Hub Genes in Clear-Cell Renal Cell Carcinoma via Bioinformatical Analysis

Objective To identify new genes that correlate with prognosis of clear-cell renal cell carcinoma(ccRCC)via bioinformatics analysis.Methods The gene expression profiles of 62 ccRCC and 54 normal kidney tissues were available from the Gene Expression Omnibus database:GSE12606,GSE36895 and GSE66272.The differentially expressed genes were screened with GEO2R and J Venn online tools.Functional annotation including Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)was applied to identify the possible function of the hub genes involved in prognosis of ccRCC.In protein protein interaction network(PPI network),the STRING online tool was used to visualize the network of the differentially expressed genes,and the core gene was selected by MCODE App in Cytoscape software.Finally,GEPIA Survival Plot was performed to assess genes associated with worse survival.Results We totally found 648 diflerentially expressed genes,including 222 up-regulated genes and 426 down-regulated genes.PPI network showed that in 28 up-regulated genes 7(CCNE2,CDK1,CDC6,CCNB2,BUB1,TTK and PTTG1)enriched in cell cycle and 4 genes(CCNE2,CDK1,CCNB2 and RRM2)enriched in p53 signaling pathway.GEPIA Survival Plot assay revealed that ccRCC patients carrying CDK1,CCNB2,RRM2t BUB1,and PTTG1 had a worse survival.GEPIA Box Plot showed that BUB1,CCNB2,PTTG1,and RRM2 were over expressed in the ccRCC tissues in contrast to the normal tissues(P<O.OS).Conclusion ccRCC patients with the four up-regulated differentially expressed genes including BUB1,CCNB2,PTTG1,and RRM2 might manifest a poor prognosis.

NAT10-mediated ac 4 C-modified ANKZF1 promotes tumor progression and lymphangiogenesis in clear-cell renal cell carcinoma by attenuating YWHAE-driven cytoplasmic retention of YAP1

Background:Lymphatic metastasis is one of the most common metastatic routes and indicates a poor prognosis in clear-cell renal cell carcinoma(ccRCC).N-acetyltransferase 10(NAT10)is known to catalyze N4-acetylcytidine(ac4C)modification of mRNA and participate in many cellular processes.However,its role in the lymphangiogenic process of ccRCC has not been reported.This study aimed to elucidate the role of NAT10 in ccRCC lymphangiogenesis,providing valuable insights into potential therapeutic targets for intervention.Methods:ac4C modification and NAT10 expression levels in ccRCC were assessed using public databases and clinical samples.Functional investigations involved manipulating NAT10 expression in cellular and mouse models to study its role in ccRCC.Mechanistic insights were gained through a combination of RNA sequencing,mass spectrometry,co-immunoprecipitation,RNA immuno-precipitation,immunofluorescence,and site-specific mutation analyses.Results:We found that ac4C modification and NAT10 expression levels increased in ccRCC.NAT10 promoted tumor progression and lymphangiogene-sis of ccRCC by enhancing the nuclear import of Yes1-associated transcriptional regulator(YAP1).Subsequently,we identified ankyrin repeat and zinc fin-ger peptidyl tRNA hydrolase 1(ANKZF1)as the functional target of NAT10,and its upregulation in ccRCC was caused by NAT10-mediated ac4C modifi-cation.Mechanistic analyses demonstrated that ANKZF1 interacted with tyro-sine 3-monooxygenase/tryptophan 5-monooxygenase activation protein epsilon(YWHAE)to competitively inhibit cytoplasmic retention of YAP1,leading to transcriptional activation of pro-lymphangiogenic factors.Conclusions:These results suggested a pro-cancer role of NAT10-mediated acetylation in ccRCC and identified the NAT10/ANKZF1/YAP1 axis as an under-reported pathway involving tumor progression and lymphangiogenesis in ccRCC.

Using MsfNet to Predict the ISUP Grade of Renal Clear Cell Carcinoma in Digital Pathology Images

Clear cell renal cell carcinoma(ccRCC)represents the most frequent form of renal cell carcinoma(RCC),and accurate International Society of Urological Pathology(ISUP)grading is crucial for prognosis and treatment selection.This study presents a new deep network called Multi-scale Fusion Network(MsfNet),which aims to enhance the automatic ISUP grade of ccRCC with digital histopathology pathology images.The MsfNet overcomes the limitations of traditional ResNet50 by multi-scale information fusion and dynamic allocation of channel quantity.The model was trained and tested using 90 Hematoxylin and Eosin(H&E)stained whole slide images(WSIs),which were all cropped into 320×320-pixel patches at 40×magnification.MsfNet achieved a micro-averaged area under the curve(AUC)of 0.9807,a macro-averaged AUC of 0.9778 on the test dataset.The Gradient-weighted Class Activation Mapping(Grad-CAM)visually demonstrated MsfNet’s ability to distinguish and highlight abnormal areas more effectively than ResNet50.The t-Distributed Stochastic Neighbor Embedding(t-SNE)plot indicates our model can efficiently extract critical features from images,reducing the impact of noise and redundant information.The results suggest that MsfNet offers an accurate ISUP grade of ccRCC in digital images,emphasizing the potential of AI-assisted histopathological systems in clinical practice.

Low expression of fatty acid oxidation related gene ACADM indicates poor prognosis of renal clear cell carcinoma and is related to tumor immune infltration

This research aims to identify the key fatty acid beta-oxidation(FAO)genes that are altered in kidney renal clear cell carcinoma(KIRC)and to analyze the role of these genes in KIRC The Gene Expression Omnibus(GEO)and FAO datasets were used to identify these key genes.Wilcoxon rank sum test was used to assess the levels of acyl-CoA dehydrogenase medium chain(ACADM)between KIRC and non cancer samples.The logistic regression and Wilcoxon rank sum test were used to explore the association between ACADM and clinical features.The diagnostic performance of ACADM for KIRC was asessed using a diagnostic receiver operating ch aracteristic(ROC)curve.The co-expressed genes of ACADM were identifed in LinkedOmics database,and their function and pathway enrichment were analyzed.The correlation between ACADM expression level and immune infitration was analyzed by Gene Set Variation Analysis(GSVA)method Additionally,the proliferation,migration,and invasion abilities of KIRC cells were assessed after overexpressing ACADM.Following differential analysis and intersection,we identifed six hub genes,induding ACADM.We found that the expression level of ACADM was decreased in KIRC tissues and had a better diagnostic efect(AUC=0.916).Survival analysis suggested that patients with decreased ACADM expression had a worse prognosis.According to correlation analysis,a variety of dinical features were associated with the expression level of ACADML By analyzing the infiltration level of immune cells,we found that ACADM may be related to the enrichment of immune cells.Finally,ACADM overexpression inhibited proliferation,migration,and invasion of KIRC cells.In conclusion,our findings suggest that reduced ACADM expression in KIRC patients is indicative of poor prognosis.These results imply that ACADM may be a diagnostic and prognostic marker for individuals with KIRC,offering a reference for dinicians in diagnosis and treatment.

Network pharmacology and molecular docking analysis reveal insights into the molecular mechanism of Gualou Qumai Wan in clear cell renal cell carcinoma

Background:To initially clarify the potential therapeutic targets and pharmacological mechanism regarding Gualou Qumai Wan(GQW),a kind of traditional Chinese medicine(TCM),in clear cell renal cell carcinoma(ccRCC)by virtue of the network pharmacology analysis and molecular docking analysis.Methods:The screening of bioactive components and targets of GQW was based on the Traditional Chinese Medicine System Pharmacology(TCMSP)and the UniProt platform served for standardizing their targets.Online Mendelian Inheritance in Man(OMIM),PharmGkb,TTD,DrugBank and GeneCards databases were searched to collect the disease targets of ccRCC.Cytoscape assisted in constructing herb-compound-target(H-C-T)networks.The STRING database was searched for constructing the target protein-protein interaction(PPI)networks,while the R programming language served for analyzing GO functional terms and the KEGG pathways related to potential targets.Analyses of core genes related to survival and tumor microenvironment(TME)were conducted respectively based on the GEPIA2 database and TIMER 2.0 database.Human Protein Atlas(HPA)and The Cancer Genome Atlas(TCGA)helped to obtain core genes’protein expression as well as transcriptome expression level.Autodock Vina software validated the molecular docking regarding GQW components and pivotal targets.Results:The constructed H-C-T networks mainly had 33 compounds and 65 targets.A topological analysis of the PPI network identified that ESR1,AKT1,HIF1A,PTGS2,TP53 and VEGFA serve as core targets in the way GQW affects ccRCC.According to the GO and KEGG pathway enrichment analyses,the effects of GQW are mediated by genes related to hypoxia and oxidative stress as well as the Chemical carcinogenesis-receptor activation and PI3K-Akt signaling pathways.AKT1 shows a close relation to the recruitment of various immune cells and can remarkably affect disease prognosis according to reports.Molecular docking and molecular dynamics simulations showed that diosgenin has higher affinity with core targets.Conclusion:The study makes a comprehensive explanation of the biological activity,potential targets,as well as molecular mechanism regarding GQW against ccRCC,which promisingly assists in revealing the action mechanism of TCM formulae in disease treatment and the respective and scientific basis.

Follistatin-like protein 1 plays a tumor suppressor role in clear-cell renal cell carcinoma

Background:We previously showed that the expression of follistatin-like protein 1(FSTL1)was significantly down-regulated in metastatic clear-cell renal cell carcinoma(ccRCC).In this study,we aimed to characterize the role of FSTL1 in the development of ccRCC.Methods:The effects of FSTL1 on cell activity and cell cycle were investigated in ccRCC cell lines with altered FSTL1 expression.Gene expression microarray assays were performed to identify the major signaling pathways affected by FSTL1 knockdown.The expression of FSTL1 in ccRCC and its effect on postoperative prognosis were estimated in a cohort with 89 patients.Results:FSTL1 knockdown promoted anchorage-independent growth,migration,invasion,and cell cycle of ccRCC cell lines,whereas FSTL1 overexpression attenuated cell migration.FSTL1 knockdown up-regulated nuclear factor-κB(NF-κB)and hypoxia-inducible factor(HIF)signaling pathways,increased epithelial-to-mesenchymal transition,up-regulated interleukin-6 expression,and promoted tumor necrosis factor-α-induced degradation of NF-κB inhibitor(IκBα)in ccRCC cell lines.FSTL1 immunostaining was selectively positive in epithelial cytoplasm in the loop of Henle,and positive rate of FSTL1 was significantly lower in ccRCC tissues than in adjacent renal tissues(P<0.001).The mul-tivariate Cox regression analysis showed that the intratumoral FSTL1 expression conferred a favorable independent prognosis with a hazard ratio of 0.325(95%confidence interval 0.118-0.894).HIF-2αexpression was negatively cor-related with FSTL1 expression in ccRCC specimens(r=−0.229,P=0.044).Intratumoral expression of HIF-2α,rather than HIF-1α,significantly predicted an unfavorable prognosis in ccRCC(log-rank,P=0.038).Conclusions:FSTL1 plays a tumor suppression role possibly via repressing the NF-κB and HIF-2αsignaling pathways.To increase FSTL1 expression might be a candidate therapeutic strategy for metastatic ccRCC.

Differentiate Xp11.2 Translocation Renal Cell Carcinoma from Computed Tomography Images and Clinical Data with ResNet-18 CNN and XGBoost

This study aims to apply ResNet-18 convolutional neural network(CNN)and XGBoost to preoperative computed tomography(CT)images and clinical data for distinguishing Xp11.2 translocation renal cell carcinoma(Xp11.2 tRCC)from common subtypes of renal cell carcinoma(RCC)in order to provide patients with individualized treatment plans.Data from45 patients with Xp11.2 tRCC fromJanuary 2007 to December 2021 are collected.Clear cell RCC(ccRCC),papillary RCC(pRCC),or chromophobe RCC(chRCC)can be detected from each patient.CT images are acquired in the following three phases:unenhanced,corticomedullary,and nephrographic.A unified framework is proposed for the classification of renal masses.In this framework,ResNet-18 CNN is employed to classify renal cancers with CT images,while XGBoost is adopted with clinical data.Experiments demonstrate that,if applying ResNet-18 CNN or XGBoost singly,the latter outperforms the former,while the framework integrating both technologies performs similarly or better than urologists.Especially,the possibility of misclassifying Xp11.2 tRCC,pRCC,and chRCC as ccRCC by the proposed framework is much lower than urologists.

Aryl hydrocarbon receptor nuclear translocator 2 as a prognostic biomarker and immunotherapeutic indicator for clear cell renal cell carcinoma

Background:In many cancer types,aryl hydrocarbon receptor nuclear translocator 2(ARNT2)has been found to be associated with tumor cell proliferation and prognosis.However,the role of ARNT2 in clear cell renal cell carcinoma(ccRCC)has not been completely elucidated.In this study,the potential role of ARNT2 in ccRCC development was characterized.Methods:A pan-cancer dataset(TCGA-TARGET-GTEx)was accessed from UCSC Xena Data Browser.ARNT2 expression in normal and tumor samples was compared.Univariate Cox regression was performed to evaluate the prognostic value of ARNT2.Single sample gene set enrichment analysis(ssGSEA)was used to estimate the enrichment of functional pathways and gene signatures.CIBERSORT and ESTIMATE methods evaluated the immune infiltration.The ARNT2 expression was determined in ccRCC tissue and cell lines using RT-qPCR and Western blot.Results:ARNT2 expression was significantly dysregulated in 23 out of 30 cancer types.Pan-cancer data revealed a strong correlation between ARNT2 expression and immune modulators,immune cell infiltration,and genomic alternations.In ccRCC patients,the low-ARNT2 expression group had higher immune infiltration,CD8 T cells,and programmed cell death ligand 1 expression,as well as higher enrichment score of immunotherapeutic predictors than those in the high-ARNT2 expression group.Low-ARNT2 expression group was more responsive to immunotherapy.Moreover,low ARNT2 expression was observed in ccRCC tissue and cell lines.Conclusions:Dysregulated ARNT2 expression is involved in cancer development and the modulation of the immune microenvironment.ARNT2 can be potentially used as a prognostic indicator and an immunotherapeutic indicator for ccRCC.

Pembrolizumab combined with axitinib in the treatment of skin metastasis of renal clear cell carcinoma to nasal ala:A case report

BACKGROUND Renal clear cell carcinoma(RCC)is a malignant tumor of the genitourinary system with a predilection for males.The most common metastatic sites are the lung,liver,lymph nodes,contralateral kidney or adrenal gland,however,skin metastasis has only been seen in 1.0%-3.3%of cases.The most common site of skin metastasis is the scalp,and metastasis to the nasal ala region is rare.CASE SUMMARY A 55-year-old man with clear cell carcinoma of the left kidney was treated with pembrolizumab and axitinib for half a year after surgery and was found to have a red mass on his right nasal ala for 3 mo.The skin lesion of the patient grew rapidly to the size of 2.0 cm×2.0 cm×1.2 cm after discontinuation of targeted drug therapy due to the coronavirus disease 2019 epidemic.The patient was finally diagnosed with skin metastasis of RCC in our hospital.The patient refused to undergo surgical resection and the tumor shrank rapidly after resuming target therapy for 2 wk.CONCLUSION It is rare for an RCC to metastasize to the skin of the nasal ala region.The tumor size change of this patient before and after treatment with targeted drugs shows the effectiveness of combination therapy for skin metastasis.

Iris metastasis from clear cell renal cell carcinoma: A case report

BACKGROUND Clear cell renal cell carcinoma(ccRCC)is a common type of tumor that can metastasize to any organs and sites.However,it is extremely rare for ccRCC to metastasize to the iris.Here,we describe a rare case of iris metastasis from ccRCC with a history of left nephrectomy in 2010.CASE SUMMARY A 62-year-old male was admitted to the hospital due to blurred vision and red eyes,and a mass was found on the iris in the right eye.B-scan ultrasonography revealed a well-bounded high-density lesion at the corner of the anterior chamber at the 3-4 o’clock position.Phacoemulsification with simultaneous intraocular lens implantation and iridocyclectomy was performed in the right eye.The lesion was confirmed to be metastatic ccRCC by histological and immunohistochemical analyses.The patient was still alive at 9 mo after surgical treatment.Ocular metastasis can be an initial sign with a poor prognosis.Timely detection and treatment may improve survival.Clinicians should pay attention to similar metastatic diseases to prevent misdiagnosis leading to missed treatment oppor-tunities.CONCLUSION This report of the characteristics and successful management of a rare case of iris metastasis from ccRCC highlights the importance of a comprehensive medical history,histopathology,immunohistochemistry,and clinical manifestation for successful disease diagnosis.

A developed ant colony algorithm for cancer molecular subtype classification to reveal the predictive biomarker in the renal cell carcinoma

Background:Recently,researchers have been attracted in identifying the crucial genes related to cancer,which plays important role in cancer diagnosis and treatment.However,in performing the cancer molecular subtype classification task from cancer gene expression data,it is challenging to obtain those significant genes due to the high dimensionality and high noise of data.Moreover,the existing methods always suffer from some issues such as premature convergence.Methods:To address those problems,we propose a new ant colony optimization(ACO)algorithm called DACO to classify the cancer gene expression datasets,identifying the essential genes of different diseases.In DACO,first,we propose the initial pheromone concentration based on the weight ranking vector to accelerate the convergence speed;then,a dynamic pheromone volatility factor is designed to prevent the algorithm from getting stuck in the local optimal solution;finally,the pheromone update rule in the Ant Colony System is employed to update the pheromone globally and locally.To demonstrate the performance of the proposed algorithm in classification,different existing approaches are compared with the proposed algorithm on eight high-dimensional cancer gene expression datasets.Results:The experiment results show that the proposed algorithm performs better than other effective methods in terms of classification accuracy and the number of feature sets.It can be used to address the classification problem effectively.Moreover,a renal cell carcinoma dataset is employed to reveal the biological significance of the proposed algorithm from a number of biological analyses.Conclusion:The results demonstrate that CAPS may play a crucial role in the occurrence and development of renal clear cell carcinoma.

Single omental metastasis of renal cell carcinoma after radical nephrectomy:A case report

BACKGROUND Renal cell carcinoma(RCC)is the third most common malignancy in the genitourinary tract.The lungs,bone,lymph nodes,liver,and brain are common metastatic sites of RCC.However,there is limited literature on single omental metastasis of RCC.CASE SUMMARY We present the case of a 44-year-old man with single omental metastasis of RCC after laparoscopic radical nephrectomy.Pathological diagnosis of the resected left kidney revealed pT3a clear cell RCC(Fuhrman grade III).At 6 mo postoperatively,abdominal computed tomography revealed a 12-mm enhancing nodule in the left lower peritoneum.At 7 mo after initial operation,laparoscopic removal of the left omental nodule was performed.The pathological results indicated metastatic clear cell RCC.Currently,the patient is being treated with adjuvant pembrolizumab.CONCLUSION Omental metastasis of RCC owing to laparoscopic radical nephrectomy is rare.Urologists should be aware of the diverse nature of RCC.

Warthin-like papillary renal cell carcinoma: A case report

BACKGROUND Warthin-like papillary renal cell carcinoma(WPRCC)has been described as a rare pathological subtype of papillary renal cell carcinoma in the 2022 World Health Organization Classification of the Urinary and Male Reproductive System.Herein we report a case of WPRCC in the left kidney.CASE SUMMARY Physical examination of a previously healthy 47-year-old woman revealed a lump in her left kidney,4.5 cm×3.5 cm×3.5 cm in size.Based on the clinical information,imaging data,histmorphological features,and immunohistochemistry results,the pathological diagnosis was WPRCC in left kidney.CONCLUSION Resection of the mass in the left kidney was performed and her postoperative course was uneventful.

Correlation between Hypovitaminosis D Status and Hyperactivation of IL-6/STAT3 Signaling in Clear Cell Renal Cell Carcinoma

Objective:To analyze serum vitamin D levels in patients with clear cell renal cell carcinoma(ccRCC)by flow cytometry and to investigate the relationship between hypovitaminosis D status and hyperactivation of IL-6/STAT3 signaling in ccRCC.Methods:Eighty patients diagnosed with ccRCC by our oncology department from January 2019 to December 2021 were selected as study subjects,and the control subjects were selected from patients who were receiving health check-up from our hospital(matched according to case group:control group,1:2),with 160 healthy patients.All serum samples collected from the case-control subjects were allowed to stand for 1–2 hours,centrifuged at 3000 rpm for 10 minutes,and stored in a-80°C refrigerator,from which they were removed and thawed to measure 25-hydroxyvitamin D(25(OH)D)and interleukin 6(IL-6)levels.Results:The blood calcium level of patients in the cancer group was significantly lower than that of patients in the non-cancer group,and the difference was statistically significant(P<0.05).The IL-6 level of the cancer group was significantly higher than that of the non-cancer group.In high vitamin D state,the IL-6 level of the non-cancer group was higher than that of the cancer group,and the average concentration of IL-6 in both the cancer group and the non-cancer group was significantly higher in low vitamin D state compared with high vitamin D state(P<0.05);the correlation between hypovitaminosis D status and renal Ki-67 was found to be positive.Conclusion:The results showed that serum IL-6 levels were elevated in the cancer group and circulating serum 25(OH)D levels were negatively correlated with IL-6 levels.In addition,signal transducer and activator of transcription 3(STAT3)signaling in RCC tissues was activated in ccRCC patients and in those with low vitamin D status among the cancer group and was higher than that in those with high vitamin D status.These results suggest that hypovitaminosis D status in ccRCC patients is associated with activated IL-6/STAT3 signaling and the activation of tumor proliferation markers proliferating cell nuclear antigen(PCNA),cyclin D1,and Ki-67.

Review of renal cell carcinoma and its common subtypes in radiology

Representing 2%-3% of adult cancers, renal cell carcinoma(RCC) accounts for 90% of renal malignancies and is the most lethal neoplasm of the urologic system. Over the last 65 years, the incidence of RCC has increased at a rate of 2% per year. The increased incidence is at least partly due to improved tumor detection secondary to greater availability of high-resolution cross-sectional imaging modalities over the last few decades. Most RCCs are asymptomatic at discovery and are detected as unexpected findings on imaging performed for unrelated clinical indications. The 2004 World Health Organization Classification of adult renal tumors stratifies RCC into several distinct histologic subtypes of which clear cell, papillary and chromophobe tumors account for 70%, 10%-15%, and 5%, respectively. Knowledge of the RCC subtype is important because the various subtypes are associated with different biologic behavior, prognosis and treatment options. Furthermore, the common RCC subtypes can often be discriminated non-invasively based on gross morphologic imaging appearances, signal intensity on T2-weighted magnetic resonance images, and the degree of tumor enhancement on dynamic contrast-enhanced computed tomography or magnetic resonance imaging examinations. In this article, we review the incidence and survival data, risk factors, clinical and biochemical findings, imaging findings, staging, differential diagnosis, management options and posttreatment follow-up of RCC, with attention focused on the common subtypes.

Renal cell carcinoma: Evolving and emerging subtypes

Our knowledge of renal cell carcinoma(RCC) is rapidly expanding. For those who diagnose and treat RCC, it is important to understand the new developments. In recent years, many new renal tumors have been described and defined, and our understanding of the biology and clinical correlates of these tumors is changing. Evolving concepts in Xp11 translocation carcinoma, mucinous tubular and spindle cell carcinoma, multilocular cystic clear cell RCC, and carcinoma associated with neuroblastoma are addressed within this review. Tubulocystic carcinoma, thyroid-like follicular carcinoma of kidney, acquired cystic disease-associated RCC, and clear cell papillary RCC are also described. Finally, candidate entities, including RCC with t(6;11) translocation, hybrid oncocytoma/chromophobe RCC, hereditary leiomyomatosis and RCC syndrome, and renal angiomyoadenomatous tumor are reviewed. Knowledge of these new entities is important for diagnosis, treatment and subsequent prognosis. This review provides a targeted summary of new developments in RCC.

Advances of multidetector computed tomography in the characterization and staging of renal cell carcinoma

Renal cell carcinoma(RCC) accounts for approximately 90%-95% of kidney tumors. With the widespread use of cross-sectional imaging modalities, more than half of RCCs are detected incidentally, often diagnosed at an early stage. This may allow the planning of more conservative treatment strategies. Computed tomography(CT) is considered the examination of choice for thedetection and staging of RCC. Multidetector CT(MDCT) with the improvement of spatial resolution and the ability to obtain multiphase imaging, multiplanar and threedimensional reconstructions in any desired plane brought about further improvement in the evaluation of RCC. Differentiation of RCC from benign renal tumors based on MDCT features is improved. Tumor enhancement characteristics on MDCT have been found closely to correlate with the histologic subtype of RCC, the nuclear grade and the cytogenetic characteristics of clear cell RCC. Important information, including tumor size, localization, and organ involvement, presence and extent of venous thrombus, possible invasion of adjacent organs or lymph nodes, and presence of distant metastases are provided by MDCT examination. The preoperative evaluation of patients with RCC was improved by depicting the presence or absence of renal pseudocapsule and by assessing the possible neoplastic infiltration of the perirenal fat tissue and/or renal sinus fat compartment.

Molecular genetics and immunohistochemistry characterization of uncommon and recently described renal cell carcinomas

Renal cell carcinoma （RCC） compromises multiple types and has been emerging dramatically over the recent several decades. Advances and consensus have been achieved targeting common RCCs, such as clear cell carcinoma, papillary RCC and chromophobe RCC. Nevertheless, little is known on the characteristics of several newly-identified RCCs, including clear cell （tubulo） papillary RCC, Xpl 1 translocation RCC, t（6;11） RCC, succinate dehydrogenase （SDH）-deficient RCC, acquired cystic disease- associated RCC, hereditary leiomyomatosis RCC syndrome-associated RCC, ALK translocation RCC, thyroid-like follicular RCC, tubulocystic RCC and hybrid oncocytic/chromophobe tumors （HOCT）. In current review, we will collect available literature of these newly-described RCCs, analyze their clinical pathologic characteristics, discuss their morphologic and immunohistologic features, and finally summarize their molecular and genetic evidences. We expect this review would be beneficial for the understanding of RCCs, and eventually promote clinical management strategies.

Epigenomics of clear cell renal cell carcinoma： mechanisms and potential use in molecular pathology

Clear cell renal cell carcinoma （ccRCC） is one frequent form of urologic malignancy with numerous genetic and epigenetic alterations. This review summarizes the recent major findings of epigenetic alterations including DNA methylation, histone modifications, microRNAs and recently identified long noncoding RNAs in the development and progression of ccRCC. These epigenetic profilings can provide a promising means of prognostication and early diagnosis for patients with ccRCCs. With the developed high- throughput technologies nowadays, the epigenetic analyses will have possible clinical applications in the molecular pathology of ccRCC.