Eosinophilic solid and cystic renal cell carcinoma with aggressive behavior:Two case reports

BACKGROUND Eosinophilic solid and cystic(ESC)renal cell carcinoma(RCC),a unique and emerging subtype of RCC,has an indolent nature;in some rare instances,it may exhibit metastatic potential.Current cases are inadequate to precisely predict the clinical outcome of ESC RCC and determine treatment choices.CASE SUMMARY Herein,we report two patients with ESC RCC.Patient 1 was a young woman with classical pathological characteristics.Patient 2 was a 52-year-old man with multifocal metastases,involving the pulmonary hilar and mediastinal lymph nodes,liver,brain,mesosternum,vertebra,rib,femur,and symphysis pubis.Awareness of ESC RCC,along with its characteristic architecture and immunophenotype,would contribute to making a definitive diagnosis,even on core biopsy samples.CONCLUSION The discovery of ESC RCC molecular signatures may provide new therapeutic strategies in the future.

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.

Endobronchial metastasis secondary to renal clear cell carcinoma:A case report

BACKGROUND Endobronchial metastases(EBMs)are tumours that metastasise from a malignant tumour outside the lungs to the central and subsegmental bronchi,and are visible under a bronchofibrescope.Most EBMs are formed by direct invasion or metastasis of intrathoracic malignant tumours,such as lung cancer,oesophageal cancer or mediastinum tumours.Renal cell carcinoma(RCC),accounting for 2%to 3%of all tumours,is a common malignant tumour of the urinary system.Renal clear cell carcinoma(RCCC)constitutes the predominant pathological subtype of RCC,comprising approximately 70%to 80%of all RCC cases.RCCC can spread and metastasise through arterial,venous and lymphatic circulation to almost all organs of the body.Moreover,lung,bone,liver,brain and local recurrence are the most common metastatic neoplasms of RCCC.However,EBM from RCCC has a low complication rate and is often misdiagnosed as primary lung cancer.CASE SUMMARY A 71-year-old male patient who had undergone radical left nephrectomy 7 years prior due to RCCC was referred to our hospital due to a 1-mo history of productive cough.The results of an enhanced chest CT scan indicated the presence of a soft tissue nodule in the upper lobe of the left lung,and flexible bronchoscopy revealed a hypervascular lesion in the bronchus of the left lung's superior lobe.Therefore,the patient underwent thoracoscopic left superior lobe wedge resection,and pathology confirmed EBM from the RCCC.CONCLUSION EBM from RCCC has a low incidence and no characteristic clinical manifestations in the early stage.If a bronchial tumour is found in a patient with RCCC,the possibility of bronchial metastatic cancer should be considered.

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.

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.

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.

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.

Synchronous sporadic bilateral multiple chromophobe renal cell carcinoma accompanied by a clear cell carcinoma and a cyst: A case report

BACKGROUND Renal cell carcinomas are usually unilateral.However,they are bilateral in 2%to 4%of sporadic cases and is considerably more common in familial cases.Synchronous sporadic bilateral multiple chromophobe renal cell carcinoma(CHRCC)with different subtypes is rare.CASE SUMMARY In this case report,we describe a case of synchronous bilateral CHRCC with two histological variants,accompanied by a clear cell carcinoma and a cyst in a 50-year-old male.The patient underwent retroperitoneal laparoscopic bilateral nephron-sparing surgery and there was no serious postoperative renal dysfunction.CONCLUSION We report a rare case of synchronous bilateral CHRCC with two histological variants associated with a clear cell carcinoma and a cyst.

Ipsilateral synchronous papillary and clear renal cell carcinoma:A case report and review of literature

BACKGROUND There is limited information on ipsilateral synchronous papillary renal cell carcinoma(PRCC)and clear cell renal cell carcinoma(CCRCC).Therefore,these rare tumors are often misdiagnosed preoperatively as a single tumor with intrarenal metastasis or some other diseases.Effective management and long-term overall survival might be affected because the prognosis of the two tumors differs.CASE SUMMARY We describe a case of ipsilateral synchronous PRCC and CCRCC with two histological variants in a 72-year-old man,whose mass was found incidentally,with no other chief complaints and vital signs were normal.Initial ultrasound revealed a hypoechoic lobular mass with a volume of 7.8 cm×4.8 cm×2.8 cm in the middle to lower pole of the left kidney.A subsequent contrast-enhanced computed tomography scan showed a single endophytic mass of 7.5 cm in diameter.The patient underwent laparoscopic left radical nephrectomy.A final diagnosis of ipsilateral synchronous PRCC and CCRCC was confirmed by pathological examination.There was no recurrence or metastasis after 25 mo follow-up.CONCLUSION We report a case of ipsilateral synchronous PRCC and CCRCC,and review related literature to estimate the prevalence of similar cases.The above descriptions may be expected to help understand the disease,and improve diagnosis in the future.

Thyroid follicular renal cell carcinoma excluding thyroid metastases:A case report

BACKGROUND Thyroid follicular renal cell carcinoma is a special type of renal cell carcinoma newly recognized in recent years.It has attracted attention because of its unique histology,immunophenotype,and clinical characteristics.It has a very low incidence,and the number of case reports available for review is limited.Moreover,a thyroid mass with type of tumour is rare.CASE SUMMARY We report a case of a renal mass with a bilateral thyroid mass that was accidentally discovered in a 60-year-old man during physical examination.B-mode ultrasound showed a hypoechoic mass in the middle and lower parenchyma of the right kidney,and computed tomography showed an iso-density shadow tumour in the right kidney.Contrast agents had a significant continuous enhancement effect on the tumour,and the enhancement was not uniform.After partial nephrectomy,pathological analysis was performed to rule out the possibility that the renal tumour was caused by thyroid tumour metastasis.Needle biopsy of the thyroid tumour confirmed that the renal cell carcinoma was not related to the thyroid tumour.The patient was alive at the last postoperative follow-up.CONCLUSION This is the third published case in which thyroid tumour biopsy was performed to confirm that thyroid follicular renal cell carcinoma is not thyroid related.

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.

Novel immunotherapy approaches for metastatic urothelial and renal cell carcinoma

The treatment of metastatic renal cell carcinoma(RCC)and urothelial carcinoma(UC)remains a major challenge.Past research has implicated the immune system in tumor surveillance of both malignancies,leading to the application of immunotherapy agents for both cancers.Among them,the most promising agents are the checkpoint blockade drugs,such as antibodies targeting the cytotoxic T-lymphocyte-associated antigen 4(CTLA-4),programmed death receptor 1(PD-1),and PD-1 ligand(PD-L1).In normal physiology,these immune checkpoints act as inhibitory signals to fine-tune the duration and strength of immune reactions,which is pivotal for maintaining self-tolerance.However,tumor cells also utilize immune checkpoint pathways to evade anti-tumor immune response,leading to disease progression and metastasis.Thus,there has been intense preclinical and clinical effort focused on the application of checkpoint inhibitors in metastatic RCC and UC.To date,nivolumab(anti-PD-1)and atezolizumab(anti-PD-L1)have been approved for the treatment of metastatic RCC and UC,respectively.Despite these successes,challenges remain in how to further improve response rates to immunotherapy and how to select patients that will benefit from this approach.In this report,we review existing data and research on immunotherapy in metastatic RCC and UC.

Metastatic clear cell renal cell carcinoma in isolated retroperitoneal lymph node without evidence of primary tumor in kidneys: A case report

BACKGROUND Retroperitoneal lymph node dissection(RPLND)plays a diagnostic,therapeutic,and prognostic role in myriad urologic malignancies,including testicular carcinoma,renal cell carcinoma(RCC),and upper urinary tract urothelial carcinoma.RCC represents 2%of all cancers with approximately 25%of patients presenting with advanced disease.Clear cell RCC(CCRCC)is the most common RCC,accounting for 75%-80%of all RCC.CASE SUMMARY A 71-year-old man presented with a history of benign prostatic hypertrophy.He was asymptomatic without any hematuria,pain,or other urinary symptoms.A computed tomography(CT)scan of the abdomen and pelvis showed a 1.8 cm left retroperitoneal lymph node.There was no evidence of renal pathology.A core biopsy was performed of the left para-aortic lymph node.Although the primary tumor site was unknown,the morphological and immunohistochemical features were most consistent with CCRCC.A RPLND was performed which revealed a single mass 5.5 cm in greatest dimension with extensive necrosis.The retroperitoneal lymph node was most compatible with CCRCC.A nephrectomy was not conducted as a renal mass had not been detected on any prior imaging studies.The patient did not receive any type of adjuvant therapy.The patient underwent surveillance with serial CT scans with contrast of the chest,abdomen,and pelvis for the next 5 years,all of which demonstrated no recurrent or metastatic disease and no evidence of retroperitoneal adenopathy.CONCLUSION Our unique case emphasizes the therapeutic role of metastasectomy in metastatic CCRCC even in the absence of primary tumor in the kidneys.

Simultaneous robot-assisted approach in a super-elderly patient with urothelial carcinoma and synchronous contralateral renal cell carcinoma:A case report

BACKGROUND It is rare for urothelial and renal cell carcinomas to coexist in the same patient,and even rarer for them to be detected simultaneously.Because of this rarity,a standard treatment has not been established and studies about overall survival are scarce.Therefore,physicians must modify treatments according to the individual’s situation and the stage of each disease.In recent years,with advances in the instruments and techniques,minimal invasive robotic surgeries have become available for advanced-stage or high-risk patients.CASE SUMMARY An 85-year-old woman with a medical history of hypertension and hyperlipidemia visited our institution.She had visited her local hospital complaining of intermittent,painless,gross hematuria that had started 3 mo earlier.On computed tomography,a right renal mass and left proximal ureteral mass with hydronephrosis were found simultaneously.We decided to perform robot-assisted surgery on both sides during one operation.Considering renal function and kidney loading,right partial nephrectomy was performed first,followed by left nephroureterectomy with bladder cuff excision.At the 6-mo follow-up,no specific symptoms were reported and dialysis was not considered.There were no unusual findings in the imaging study,and regular follow-up and imaging studies are scheduled.CONCLUSION This case report assessed the feasibility of simultaneous minimal invasive robotic surgery as an alternative to conventional open or laparoscopic surgery.

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.

Long Non-coding RNA MEG3 Induces Renal Cell Carcinoma Cells Apoptosis by Activating the Mitochondrial Pathway

Summary： This study aimed to examine the effect of long non-coding RNA （LncRNA） MEG3 on the biological behaviors of renal cell carcinoma （RCC） cells 786-0 and the possible mechanism. MEG3 expression levels were detected by RT-qPCR in Rmaor tissues and adjacent non-tumor tissues from 29 RCC patients and in RCC lines 786-0 and SN12 and human embryonic kidney cell line 293T. Plasmids GV144-MEG3 （MEG3 overexpression plasmid） and GV144 （control plasmid） were stably transfected into 786-0 cells by using lipofectamine 2000. Cell viabilities were determined by MTT, cell apoptosis rates by flow cytometry following PE Annexin V and 7AAD staining, apoptosis-related protein expressions by Western blotting, and Bcl-2 mRNA by RT-qPCR in the transfected cells. The results showed that MEG3 was evidently downregulated in RCC tissues （P〈0.05） and RCC cell lines （P〈0.05）. The viabilities of 786-0 cells were decreased significantly after transfection with GV144-MEG3 for over 24 h （P〈0.05）. Consistently, the apoptosis rate was significantly increased in 786-0 cells transfected with GV144-MEG3 for 48 h （P〈0.05）. Furthermore, overexpression of MEG3 could reduce the expression of Bcl-2 and procaspase-9 proteins, enhance the expression of cleaved caspase-9 protein, and promote the release of cytochrome c protein to cytoplasm （P〈0.05）. Additionally, Bcl-2 mRNA level was declined by MEG3 overexpression （P〈0.05）. It was concluded that MEG3 induces the apoptosis of RCC cells possibly by activating the mitochondrial pathway.