Integrative analysis of deoxyribonuclease 1-like 3 as a potential biomarker in renal cell carcinoma.

Background: Clear cell renal cell carcinoma (ccRCC), the most common subtype of renal cell carcinoma (RCC), is insensitive to radiotherapy and chemotherapy after surgery. Deoxyribonuclease 1-like 3 (DNASE1L3), an endonuclease that cleaves both membrane-encapsulated single- and double-stranded DNA, suppresses cell cycle progression, proliferation and metabolism in hepatocellular carcinoma cells. There is currently no established link between DNASE1L3 and RCC inhibition. We are gonging to explored the mechanism underlying the relationship between DNASEL1L3 and RCC. Methods: RNA sequencing data for RCC tissue and peritumoral tissue were downloaded from The Cancer Genome Atlas database and analyzed. The expression levels of DNASE1L3 in RCC and normal samples were verified using the Gene Expression Omnibus (GEO) database, Human Protein Atlas database and western blotting. The role and potential mechanism of DNASE1L3 were investigated by analysis of immune-related databases and wound healing, invasion, cell counting kit 8 and immunofluorescence assays. Results: We revealed that DNASE1L3 expression was downregulated in RCC group compared with control group [The Cancer Genome Atlas (TCGA): 7.98 vs. 10.87, P<0.001]. Meanwhile, DNASE1L3 expression correlated with the clinical characteristics of patients. Patients with low DNASE1L3 expression had worse survival (P<0.001) and larger (r=-0.32, P<0.001) and heavier tumors (r=-0.17, P<0.001). DNASE1L3 overexpression inhibited the proliferation (786-O: 0.135±0.014 vs. 0.322±0.027, P<0.001) and invasion (786-O: 1,479±134 vs. 832±67, P<0.05) of RCC cells. The expression of DNASE1L3 was significantly correlated with the tumor immune microenvironment and drug sensitivity in ccRCC. Moreover, the level of the key phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway protein P-AKT was decreased in the group of cells transfected with DNASE1L3. Conclusions: This study strongly suggest that DNASE1L3 may be a promising potential biomarker for the diagnosis and treatment of ccRCC patients.

Two-dimensional correlated spectroscopy distinguishes clear cell renal cell carcinoma from other kidney neoplasms and non-cancer kidney.

Background: Routinely used clinical scanners, such as computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound (US), are unable to distinguish between aggressive and indolent tumor subtypes in masses localized to the kidney, often leading to surgical overtreatment. The results of the current investigation demonstrate that chemical differences, detected in human kidney biopsies using two-dimensional COrrelated SpectroscopY (2D L-COSY) and evaluated using multivariate statistical analysis, can distinguish these subtypes. Methods: One hundred and twenty-six biopsy samples from patients with a confirmed enhancing kidney mass on abdominal imaging were analyzed as part of the training set. A further forty-three samples were used for model validation. In patients undergoing radical nephrectomy, biopsies of non-cancer kidney cortical tissue were also collected as a non-cancer control group. Spectroscopy data were analyzed using multivariate statistical analysis, including principal component analysis (PCA) and orthogonal projection to latent structures with discriminant analysis (OPLS-DA), to identify biomarkers in kidney cancer tissue that was also classified using the gold-standard of histopathology. Results: The data analysis methodology showed good separation between clear cell renal cell carcinoma (ccRCC) versus non-clear cell RCC (non-ccRCC) and non-cancer cortical tissue from the kidneys of tumor-bearing patients. Variable Importance for the Projection (VIP) values, and OPLS-DA loadings plots were used to identify chemical species that correlated significantly with the histopathological classification. Model validation resulted in the correct classification of 37/43 biopsy samples, which included the correct classification of 15/17 ccRCC biopsies, achieving an overall predictive accuracy of 86%, Those chemical markers with a VIP value >1.2 were further analyzed using univariate statistical analysis. A subgroup analysis of 47 tumor tissues arising from T1 tumors revealed distinct separation between ccRCC and non-ccRCC tissues. Conclusions: This study provides metabolic insights that could have future diagnostic and/or clinical value. The results of this work demonstrate a clear separation between clear cell and non-ccRCC and non-cancer kidney tissue from tumor-bearing patients. The clinical translation of these results will now require the development of a one-dimensional (1D) magnetic resonance spectroscopy (MRS) protocol, for the kidney, using an in vivo clinical MRI scanner.

Initial single centre experience of Aquablation of the prostate using the AquaBeam system with athermal haemostasis for the treatment of benign prostatic hyperplasia: 1-year outcomes.

PURPOSE: Aquablation using the AquaBeam system combines real-time image guidance and robotics to enable precise and heat-free removal of prostatic tissue with a high velocity water jet. The aim of this study is to report the outcomes of Aquablation up to 1 year in a single centre within the UK employing an athermal approach to haemostasis. METHODS: Fifty-five consecutive men underwent Aquablation between September 2017 and December 2018 (as part of OPEN WATER trial). Standard Aquablation was performed with the AquaBeam system (PROCEPT® BioRobotics) with 2 passes of Aquablation followed by bladder washout with application of continuous bladder irrigation via a catheter on a continuous traction device. Patients were followed up at 3 and 12 months. The data were prospectively collected on patient demographics, uroflowmetry, prostate volume, International Prostate Symptom Score (IPSS), Male Sexual Health Questionnaire for Ejaculatory Dysfunction (MSHQ-EjD) and International Index of Erectile Function (IIEF-15). RESULTS: The mean age was 64.1 ± 7.9 years. Operating time was 26.9 ± 9.2 min. Mean prostate volume decreased from 58.2 ± 23.9 cc to 33.2 ± 12.9 cc (p < 0.0001). There were significant improvements at the 12 month follow-up in maximum urinary flow rate (9.9 ± 5.1 ml/s vs. 23.9 ± 11.6 ml/s), IPSS (21.7 ± 7.4 vs. 6.1 ± 4.2) and quality of life score (4.8 ± 1.1 vs. 1.4 ± 1.4) (p < 0.0001). There was no significant change in IIEF-15 and MSHQ-EjD scores. There were 8 (14.5%) Clavien grade 2 or higher complications. CONCLUSION: Our single centre experience suggests Aquablation using an entirely athermal approach is a safe cavitating procedure resulting in significant LUTS improvement comparable to standard cavitating procedures with greater preservation of sexual function.

Utility of cytokeratin 7, S100A1 and caveolin-1 as immunohistochemical biomarkers to differentiate chromophobe renal cell carcinoma from renal oncocytoma.

BACKGROUND: Differentiation of chromophobe renal cell carcinoma (chRCC) from benign renal oncocytoma (RO) can be challenging especially when there are overlapping histological and morphological features. In this study we have investigated immunohistochemical biomarkers (cytokeratin 7/CK7, Caveolin-1/Cav-1 and S100 calcium-binding protein A1/S100A1) to aid in this difficult differentiation and attempted to validate their use in human renal tumour tissue to assess their discriminatory ability, particularly for chRCC and RO, in an Australian cohort of patients. METHODS: Retrospective study was carried out of archived formalin-fixed paraffin-embedded renal tumours from tumour nephrectomy specimens of 75 patients: 30 chRCC, 15 RO and 30 clear cell RCC (ccRCC). Sections were cut and immunostained with specific polyclonal antibodies of CK7, Cav-1 and S100A1. Morphometry was used to determine expression patterns of the biomarkers using Aperio ImageScope. Results were assessed with student t-test and ANOVA with significance at P<0.05. RESULTS: From this cohort, male-to-female ratio was 1.9:1. Median age was 64 (45-88 years) and median tumour size was 3.8 cm (range, 1.2-18 cm). There were 47 (62.7%) T1, 7 T2, 20 T3 and one T4 stage of RCC; with 2 patients presenting with M1 stage. There was significantly higher CK7 expression in chRCC compared to RO (P=0.03), and chRCC also had a different staining pattern and higher expression of Cav-1 compared to RO. There was higher expression of S100A1 in RO compared to chRCC. CONCLUSIONS: Immunohistochemical staining and standard morphometry of CK7, Cav-1 and S100A1 can aid in the differentiation of chRCC and RO. This may guide clinicians in management of patients when faced with difficult diagnostic histological distinction between the two tumour subtypes.

Prostate specific membrane antigen (PSMA) expression in vena cava tumour thrombi of clear cell renal cell carcinoma suggests a role for PSMA-driven tumour neoangiogenesis.

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is a malignant renal neoplasm with a peculiar propensity to propagate as a contiguous tumor extension via the renal vein and inferior vena cava, occasionally reaching the right atrium. This intravascular tumor extension, often referred to as a tumor thrombus, represents the active growing front of the cancer. Prostate specific membrane antigen (PSMA), a glycoprotein that is extensively used in prostate cancer diagnostics, is a useful vascular marker for a variety of solid tumors. It is expressed in renal carcinomas. The aim of the current investigation was to analyse and compare the expression of PSMA at the growing front of the vena cava tumor extension with that found in the primary renal lesion. METHODS: Immunohistochemical (IHC) analysis of PSMA and CD34 was performed on archived paraffin embedded vena cava tumour thrombus tissue and matching renal tumours. These specimens were collected from radical nephrectomies of 10 patients with vena cava invasive (pT3b) ccRCC in a large tertiary hospital in Australia. Quantitative and qualitative morphometric analysis of PSMA IHC expression was performed with Aperio ImageScope morphometry using intensity and positive pixel counts of CD34 and PSMA from the IVC tumour slides and the corresponding renal tumour mass. RESULTS: PSMA and CD34 immunostaining were noted in the neovasculature of IVC tumour and renal tumour tissue. There was a higher PSMA/CD34 positive pixel count ratio noted in IVC tumour tissue when compared to renal tumour tissue. PSMA showed consistently increased expression in vena cava tumour, in comparison with the renal tumour mass. CONCLUSIONS: Intravascular venous tumour extension expresses PSMA more intensely compared to intrarenal tumour tissue neovasculature. Our data suggest a possible mechanism for PSMA in neoangiogenesis and local progression of ccRCC and therefore its usefulness as a biomarker of neoangiogenesis for future diagnostic and therapeutic advancements.

Chronic kidney cortical damage is associated with baseline kidney function and albuminuria in patients managed with radical nephrectomy for kidney tumours.

This study evaluated the relationship between histological markers of chronic kidney damage in patients undergoing radical nephrectomy for kidney tumours and preoperative kidney function, degree of albuminuria, and changes in glomerular volume. A schema to grade chronic kidney damage could be used to identify patients at risk of developing CKD following nephrectomy. Non-neoplastic cortical tissue was sourced from 150 patients undergoing radical nephrectomy for suspected kidney cancer. This tissue was evaluated for indicators of chronic damage, specifically: glomerulosclerosis, arteriosclerosis, interstitial fibrosis, and tubular atrophy. Glomerular volume was determined using the Weibel and Gomez method. Associations between these parameters and both estimated glomerular filtration rate (eGFR) and albumin-creatinine ratio (ACR) were determined using either a Mann-Whitney U-test or a Kruskal-Wallis ANOVA. Associations between both eGFR and ACR and glomerular volume were assessed using linear regression. eGFR was inversely associated with the degree of glomerulosclerosis (p < 0.001), vascular narrowing (p = 0.002), tubular atrophy (p < 0.001), and interstitial fibrosis (p < 0.001). ACR was associated only with the degree of interstitial fibrosis (p = 0.02) and tubular atrophy (p = 0.02). Glomerular volume was greater for males, diabetics, hypertensive patients, and patients with a greater degree of interstitial fibrosis. Glomerular volume was positively associated with ACR. A schema to grade chronic damage was developed. The proposed schema is associated with baseline clinical indices of kidney function and damage. Longitudinal validation is necessary to determine the prognostic utility of this schema.

Nuclear factor-kappa B subunits and their prognostic cancer-specific survival value in renal cell carcinoma patients.

Better characterisation and understanding of renal cell carcinoma (RCC) development and progression lead to better diagnosis and clinical outcomes. In this study, expression of nuclear factor-kappa B (NF-κB) subunits: p65 (RelA), p105/p50, p100/p52, and cRel in RCC tissue were compared with corresponding normal kidney, along with tumour characteristics and survival outcome. Ninety-six cases of RCC with paired normal kidney were analysed. Clinicopathological data, demographics and survival data were available. Immunohistochemistry (IHC) for NF-κB subtypes was analysed using the Aperio digital pathology system for overall cellular expression and localisation. The prognostic cancer-specific survival value of the subunits in RCC patients was analysed. Approximately 50% of patients had clinical stage T1, with 22 patients having metastases at presentation. RCC subtypes were: clear cell (n = 76); papillary (n = 11); chromophobe (n = 5); clear cell tubulopapillary (n = 3); and one multilocular cystic RCC. Median follow up was 54.5 months (0.2-135), with 28 deaths at time of analysis. NF-κB p65 had higher overall and nuclear expressions, with lower overall and nuclear expressions of p50, p52 and cRel in RCC compared with normal kidney. Higher expressions of p65 (nuclear), p52 (overall and nuclear) and p50 (overall) correlated significantly with worse cancer-specific survival. This is the first large series of analysis of expression of NF-κB subunits in RCC. Especially with regards to the less studied subunits (p52, p50, cRel), our results allow a better understanding the role of NF-κB in RCC development and progression, and may pave the way for future targeted NF-κB subunit specific therapies.

Association between preoperative hydration status and acute kidney injury in patients managed surgically for kidney tumours.

PURPOSE: The purpose of this study was to investigate whether preoperative dehydration and intraoperative hypotension were associated with postoperative acute kidney injury in patients managed surgically for kidney tumours. METHODS: A retrospective analysis of 184 patients who underwent nephrectomy at a single centre was performed, investigating associations between acute kidney injury after nephrectomy, and both intraoperative hypotension and preoperative hydration/volume status. Intraoperative hypotension was defined as mean arterial pressure < 60 mmHg for ≥ 5 min. Urine conductivity was evaluated as a surrogate measure of preoperative hydration (euhydrated < 15 mS/cm; mildly dehydrated 15-20 mS/cm; dehydrated > 20 mS/cm). Multivariable logistic regression was used to evaluate associations between exposures and the primary outcome, with adjustment made for potential confounders. RESULTS: Patients who were dehydrated and mildly dehydrated had an increased risk of acute kidney injury (adjusted odds ratio [aOR] 4.1, 95% CI 1.3-13.5; and aOR 2.4, 95% CI 1.1-5.3, respectively) compared with euhydrated patients (p = 0.009). Surgical approach appeared to modify this effect, where dehydrated patients undergoing laparoscopic surgery were most likely to develop acute kidney injury, compared with patients managed using an open approach. Intraoperative hypotension was not associated with acute kidney injury. CONCLUSION: Preoperative dehydration may be associated with postoperative acute kidney injury. Avoiding dehydration in the preoperative period may be advisable, and adherence to international evidence-based guidelines on preoperative fasting is recommended.

Indoxyl Sulfate Induces Apoptosis and Hypertrophy in Human Kidney Proximal Tubular Cells.

Indoxyl sulfate (IS) is a protein-bound uremic toxin that accumulates in patients with declining kidney function. Although generally thought of as a consequence of declining kidney function, emerging evidence demonstrates direct cytotoxic role of IS on endothelial cells and cardiomyocytes, largely through the expression of pro-inflammatory and pro-fibrotic factors. The direct toxicity of IS on human kidney proximal tubular epithelial cells (PTECs) remains a matter of debate. The current study explored the effect of IS on primary cultures of human PTECs and HK-2, an immortalized human PTEC line. Pathologically relevant concentrations of IS induced apoptosis and increased the expression of the proapoptotic molecule Bax in both cell types. IS impaired mitochondrial metabolic activity and induced cellular hypertrophy. Furthermore, statistically significant upregulation of pro-fibrotic (transforming growth factor-ß, fibronectin) and pro-inflammatory molecules (interleukin-6, interleukin-8, and tumor necrosis factor-α) in response to IS was observed. Albumin had no influence on the toxicity of IS. The results of this study suggest that IS directly induced a pro-inflammatory and pro-fibrotic phenotype in proximal tubular cells. In light of the associated apoptosis, hypertrophy, and metabolic dysfunction, this study demonstrates that IS may play a role in the progression of chronic kidney disease.

The Correlates of Kidney Dysfunction ­ Tumour Nephrectomy Database (CKD-TUNED) Study: Protocol for a Prospective Observational Study

Background: Tumour nephrectomy conveys a significant risk of adverse renal functional outcomes postoperatively, however there are limited strategies for predicting patients at increased risk of these outcomes. The Correlates of Kidney Dysfunction ­ Tumour Nephrectomy Database (CKD-TUNED) study is a prospective observational study evaluating the risk of chronic kidney disease and end-stage kidney disease in tumour nephrectomy patients. Methods: The CKDTUNED study involves analysis of clinical data and collection of tissue, urine and blood samples for the purposes of forming a tissue repository resource for future investigation. Recruitment began in 2013 and is expected to continue until 2023, with a projected sample size between 700-1000 subjects. Results: All relevant ethics and site-specific approvals have been granted and all relevant infrastructure is in place. Study methods are undergoing validation and refinement. As of June 2017 there are 267 participants enrolled in the study. Conclusion: It is anticipated that this study will have the potential to identify risk factors for adverse renal functional outcomes following tumour nephrectomy, which can be used in the development of predictive models with clinical utility, and in turn improve patient outcomes.

Factors associated with acutely elevated serum creatinine following radical tumour nephrectomy: the Correlates of Kidney Dysfunction-Tumour Nephrectomy Database study.

BACKGROUND: To identify factors associated with acutely elevated serum creatinine (SCr) within 7 days of radical tumour nephrectomy. METHODS: The study population consisted of 130 consecutive patients managed for renal tumours. The primary outcome was acute kidney injury (AKI) (defined as SCr increase ≥50% above baseline), assessed using multivariable logistic regression analysis. The secondary outcome was SCr percentage increase, assessed using multivariable linear regression analysis. RESULTS: Following nephrectomy, the mean percentage increase in SCr in the first week was 55%±29%, and 77 (59%) patients experienced AKI. Independent predictors of AKI post-nephrectomy were male gender [adjusted odds ratio (OR): 2.67; 95% confidence interval (95% CI): 1.01, 6.93], urine albumin-creatinine ratio (OR: 0.66; 95% CI: 0.47, 0.91), preoperative estimated glomerular filtration rate (eGFR) (OR: 1.03; 95% CI: 1.00, 1.05), laparoscopic nephrectomy (OR: 3.02; 95% CI: 1.00, 9.12), and non-clear cell renal cell carcinoma (RCC) (OR: 2.93; 95% CI: 1.04, 8.29). Independent predictors of a SCr increase were male gender (ß: 12.0; 95% CI: 2.69, 21.3), urine albumin-creatinine ratio (ß: -3.36; 95% CI: -6.55, -0.16), preoperative eGFR (ß: 0.38; 95% CI: 0.10, 0.66), laparoscopic nephrectomy (ß: 12.7; 95% CI: 1.05, 24.3) and obesity (ß: 9.94, 95% CI: 0.61, 19.3). CONCLUSIONS: Male gender, albuminuria, eGFR and laparoscopic nephrectomy independently associated with acutely elevated serum creatinine following radical tumour nephrectomy.

A Rare Case of Solitary Kidney Metastasis Following Primary Laryngeal Squamous Cell Carcinoma.

Laryngeal cancer is the 14th most common malignancy worldwide, and its common subtype squamous cell carcinoma (SCC) is highly associated with tobacco use and long-term alcohol consumption. The incidence of distant metastasis from a primary laryngeal cancer has been reported to be very low, between 6.5% and 8.5%, according to published tumour registry data. Distant metastases of laryngeal SCC most commonly involve the lung, liver, bone and mediastinum, seldom involving the kidney. Renal metastasis has been well established in many other cancers such as lymphoma, lung, breast and gastric carcinoma. This report discusses the rare case of a solitary renal metastasis following a primary laryngeal SCC.

Reiter's syndrome postintravesical Bacillus Calmette-Guérin instillations.

Intravesical Bacillus Calmette-Guérin (BCG) has been a proven and effective immunotherapy treatment for superficial transitional cell carcinoma (TCC) of the bladder, especially for high-grade tumors and carcinoma in situ. Nevertheless, significant side effects are associated with BCG instillations, including fever, myalgia, malaise, dysuria, hematuria, and irritable lower urinary tract symptoms. We herein report the case of a patient who developed Reiter's syndrome following intravesical BCG instillations. A 39-year-old Chinese man presented with a 3-week history of dysuria, suprapubic pain, and pain at the tip of the penis postmicturition. Initial investigations revealed that he had microhematuria, and an ultrasound with computed tomography scan of the abdomen showed a bladder mass. Transurethral resection of the bladder tumor was performed and the patient received a single dose of intravesical mitomycin postoperatively. Results of histopathological examination revealed high-grade bladder TCC (G3pT1), and the patient was managed with intravesical BCG for 2 weeks following the surgery. Four weekly cycles of BCG were administered uneventfully; however, before the fifth instillation, the patient complained of urethral discharge, bilateral conjunctivitis, and low back pain. Reiter's syndrome was diagnosed as a rare but known complication of BCG instillation and the BCG immunotherapy was withheld. The patient was treated with nonsteroidal antiinflammatory drugs (for back pain) and eye ointment (for conjunctivitis) and his condition improved. This case report of Reiter's syndrome should be highlighted as a rare but significant complication of BCG immunotherapy and urologists should have a high index of suspicion to diagnose this rare complication.

Antegrade repositioning of Memokath stent in malignant ureteroileal anastomotic stricture.

Ureteric strictures are common and can be due to benign or malignant causes. Various surgical treatments can be used from minimally invasive endoscopic retrograde JJ stent insertion, balloon dilatation, ureterolithotomy, to open surgical exploration and repair. Memokath 051 stent is a metallic stent designed for long-term ureteral stenting in the management of ureteral strictures. The insertion of this device is usually a straightforward procedure performed endoscopically in a retrograde fashion via cystoscopy. However, this procedure can be difficult in complicated scenarios when the bladder has been removed with neoureteral reimplantations or high-grade strictures. Here, we report a case of Memokath stent insertion complicated by placement difficulties in a lady with ileal conduit due to previous ovarian cancer complicated by vesicovaginal fistula, who presented with malignant stricture of the ureteroileal anastomosis. We describe a simple yet effective antegrade technique to precisely reposition the malpositioned Memokath stent, along with illustrations.

Pilot study: use of gallium-68 PSMA PET for detection of metastatic lesions in patients with renal tumour.

BACKGROUND: In this study, we prospectively evaluate the diagnostic potential of a gallium-68 (68Ga) prostate-specific membrane antigen (PSMA)-binding ligand and positron emission tomography (PET) in detecting metastatic lesions in patients with renal tumour. The secondary aim was to determine whether the findings would result in the alteration of patient management. RESULTS: Ten patients with renal lesion and potential metastatic disease on conventional imaging were recruited. Patients underwent PSMA PET in addition to standard imaging. Nine patients underwent nephrectomy and 4 patients underwent additional targeted biopsy to provide specimens for histopathological validation. There were 89 pathological lesions on CT, of which 32 were removed or biopsied for histopathological correlation. With PSMA PET, 86 PET avid lesions were identified with 36 samples being available for analysis. Thirty-five of 36 samples were positive for renal cell carcinoma deposits, whilst 1 sample was inconclusive for diagnosis on biopsy. For the histologically confirmed lesions, there were no false-negative PSMA PET lesions; however, CT was false negative in 11. In two patients, surgical strategies were changed based on PSMA PET findings. CONCLUSIONS: PSMA PET may potentially have a role in the preoperative staging of advanced renal cell carcinoma as PET detected multiple histologically proven metastatic lesions which were false negative on CT scanning, resulting in change in surgical strategies in some patients. We cautiously support a larger study to confirm these results and to assess the longitudinal impact on patient outcomes. TRIAL REGISTRATION: Australia and New Zealand Clinical Trial Registry (ANZCTR), ACTRN12615000854538 .

A systematic review and meta-analysis of immunohistochemical biomarkers that differentiate chromophobe renal cell carcinoma from renal oncocytoma.

BACKGROUND: Numerous immunohistochemical (IHC) biomarkers have been employed to aid in the difficult differentiation between chromophobe renal cell carcinoma (chRCC) and renal oncocytoma (RO). A systematic review and meta-analysis of the published literature was carried out to summarise and analyse the evidence for discriminatory IHC biomarkers to differentiate the two entities. METHODS: PubMed database was used to identify relevant literature. Primary end point was comparison of positive immunostaining of the biomarkers in chRCC and RO, with extracted data used to calculate OR and 95% CI and statistical I(2) test of heterogeneity for multiple studies. RESULTS: One hundred and nine manuscripts were available for review. Data extracted were subjected to quantitative meta-analysis. Ten most effective biomarkers (OR of chRCC/RO and CI) are: amylase α1A (n=129, OR=0.001, 95% CI 0.0001 to 0.019); Wnt-5a (n=38, OR=0.0076, 95% CI 0.0004 to 0.015); FXYD2 (n=57, OR=130, 95% CI 14.2 to 1192.3); ankyrin-repeated protein with a proline-rich region (ARPP) (n=25, OR=0.0054, 95% CI 0.0002 to 0.12); cluster of differentiation 63 (CD63) (n=62, diffuse (chRCC) vs apical/polar (RO) stain pattern); transforming growth factor ß 1 (TGFß1) (n=34, membranous (chRCC) vs cytoplasmic (RO)); cytokeratin 7 (CK7) (11 studies, n=448, pooled OR=44.22, 95% CI 22.52 to 86.64, I(2)=15%); S100A1 (4 studies, n=124, pooled OR=0.01, 95% CI 0 to 0.03, I(2)=0%); caveolin-1 (2 studies, n=102, pooled OR=32.95, 95% CI 3.67 to 296.1, I(2)=70%) and claudin-7 (3 studies, n=89, pooled OR=24.7, 95% CI 6.28 to 97.1, I(2)=0%). CONCLUSIONS: We recommend a panel of IHC biomarkers of amylase α1A, Wnt-5a, FXYD2, ARPP, CD63, TGFß1, CK7, S100A1, caveolin-1 and claudin-7 to aid in the differentiation of chRCC and RO.

Decreased apoptosis repressor with caspase recruitment domain confers resistance to sunitinib in renal cell carcinoma through alternate angiogenesis pathways.

Apoptosis repressor with caspase recruitment domain (ARC), an endogenous inhibitor of apoptosis, is upregulated in a number of human cancers, thereby conferring drug resistance and giving a rationale for the inhibition of ARC to overcome drug resistance. Our hypothesis was that ARC would be similarly upregulated and targetable for therapy in renal cell carcinoma (RCC). Expression of ARC was assessed in 85 human RCC samples and paired non-neoplastic kidney by qPCR and immunohistochemistry, as well as in four RCC cell lines by qPCR, Western immunoblot and confocal microscopy. Contrary to expectations, ARC was significantly decreased in the majority of clear cell RCC and in three (ACHN, Caki-1 and 786-0) of the four RCC cell lines compared with the HK-2 non-cancerous human proximal tubular epithelial cell line. Inhibition of ARC with shRNA in the RCC cell line (SN12K1) that had shown increased ARC expression conferred resistance to Sunitinib, and upregulated interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF). We therefore propose that decreased ARC, particularly in clear cell RCC, confers resistance to targeted therapy through restoration of tyrosine kinase-independent alternate angiogenesis pathways. Although the results are contrary to expectations from other cancer studies, they were confirmed here with multiple analytical methods. We believe the highly heterogeneous nature of cancers like RCC predicate that expression patterns of molecules must be interpreted in relation to respective matched non-neoplastic regions. In the current study, this procedure indicated that ARC is decreased in RCC.

Decreased Expression of Inhibitor of Caspase-Activated DNase (ICAD) in Renal Cell Carcinoma - Tissue Microarray of Human Samples.

Although primary localised tumours of renal cell carcinoma (RCC) can be treated relatively successfully with surgery, metastatic RCC has poor prognosis because of late diagnosis and resistance to therapies. In the present study, we were interested in profiling the protein expression of "inhibitor of caspase-activated DNase" (ICAD), an apoptosis inhibitor, in kidney cancer and its paired normal kidney. Immunohistochemistry with automated batch staining and morphometry using digital pathology were used to compare ICAD in 121 RCC specimens with their paired normal kidney tissue. Tissue microarray of formalin-fixed, paraffin-embedded archival tissue was used. Intensity and localisation of ICAD were compared between normal and cancer samples, and against grading within the cancers. The results demonstrated that, in this cohort, ICAD was highly expressed in the proximal tubular epithelium of normal kidney, and significantly decreased in clear cell RCC tissue (p < 0.05) as well as other subtypes of RCC (p < 0.01) compared with normal kidney. There was a tendency towards nuclear localisation of ICAD in clear cell RCC, but not in other subtypes of RCC. No significant association was found between ICAD intensity and grade of RCC. In summary, down-regulation of ICAD occurs in RCC. ICAD normally inhibits DNA fragmentation and apoptosis; thus, its down-regulation was unexpected in a cancer known for its resistance to apoptosis. However, these RCC samples were from primary, not metastatic, RCC sites, and down-regulated ICAD may be part of a progressive pathway that promotes RCC metastasis.

Multifocal Primary Neoplasms in Kidney Allografts: Evaluation of Two Cases.

Renal cell carcinoma (RCC) is the fifth most common malignancy in kidney transplant recipients, with increased risk arising due to immunosuppression. De novo RCC occurrence in kidney allografts is much less common when compared with the native kidneys. Multifocal RCC in allograft kidneys is rarely described. In this report, we discuss two cases of de novo multifocal renal neoplasms in allograft kidneys. Case 1 had three distinct neoplastic lesions of >5 mm, and case 2 had four. Using the World Health Organization 2016 classification of adult renal tumours, case 1 had one clear-cell (cc) RCC (grade 3) and two papillary adenomas; all confined to the kidney. Case 2 had a nodular lesion classified as ccRCC (grade 4) with focal rhabdoid differentiation and some infiltration of renal sinus fat; a cc tubulopapillary RCC; a multilocular cystic renal neoplasm of low malignant potential; and a mucinous tubular and spindle cell carcinoma; the last three all confined to the kidney. This is the first report of mucinous tubular and spindle cell carcinoma in a kidney allograft. When considering multifocal RCC with discordant histology, it is likely that these represent independent tumourigenic events.