[Gender-specific characteristics and survival of renal cell carcinoma]

Resveratrol inhibits ACHN cells via regulation of histone acetylation

Context: The relationship between resveratrol and histone acetylation in renal cell carcinoma (RCC) has not yet been reported.Objective: To explore the functional role of resveratrol in RCC.Materials and methods: Functional experiments were performed to determine proliferatio n of ACHN cells with treatment of resveratrol (0, 7.8125, 15.625, 31.25 and 62.5 μg/mL, for 12, 24 and 48 h of culture) or 0.1 μM SAHA. The enzyme activities of MMP-2/-9 were measured by gelatine zymography and histone acetylation by Western blot.Results: When the cells were treated with 15.625, 31.25 and 62.5 μg/mL resveratrol, ACHN cells viability was 73.2 ± 3.5%, 61.4 ± 3.1%, 50.2 ± 4.7% for 12 h, 62.7 ± 4.5%, 52.4 ± 5.5%, 40.2 ± 3.8% for 24 h, and 60.8 ± 3.7%, 39.4 ± 5.1%, 37.6 ± 2.7% for 48 h, and the wound closure (%) of migration was increased from 0.6 to 0.7, 0.85, 0.9 for 12 h and from 0.23 to 0.3, 0.48, 0.59 for 24 h. The invasion rate was 8.5 ± 0.9%, 7.4 ± 0.3% and 5.8 ± 0.6%, and cell cycle was arrested at G1 from 42.5 ± 2.9% to 55.3 ± 5.7%, 59.8 ± 3.4%, 68.7 ± 4.6%. MMP-2/-9 expression (p < 0.05) was inhibited by resveratrol. The protein levels of histone acetylation (p < 0.01) was increased by resveratrol.Discussion and conclusions: Our results suggest that these effects might be related to a high level of histone acetylation, and resveratrol can be considered as an alternative treatment for RCC.

Decadal Experience of Renal Cell Carcinoma from a Tertiary Care Teaching Institute in North India

To study the current trends of renal cell carcinoma (RCC) in terms of demographic characteristics, clinical presentation, staging, mode of management, histopathology, and survival characteristics from a high volume tertiary care teaching institute in North India. We retrospectively reviewed the records of all patients of RCC between January 2006 and December 2015 and variables like age, gender, symptoms, tumor size/location/number, stage, type of surgery, histopathology, and survival characteristics were studied. One hundred forty-four patients were included in the study. Most common age group of presentation was 50-59 years (29.8%), male to female ratio was 2.5, and majority of cases were smokers. Flank pain was the most common presenting complaint (38.2%), classical triad (pain, fever, hematuria) was present in 25%, and incidental diagnosis was made in 11.1% cases. Stage T2a was most common presentation with majority of tumors present in upper pole (27.1%). Renal vein involvement (T3a) was present in 10.4%, hilar lymph node involvement in 25%, and distant metastasis was observed in 20.1% cases. Radical nephrectomy was most common surgery performed (75%) and clear cell carcinoma was the most common histopathology (75.7%) followed by papillary (11.1%). Women reported more chromophobe type and low-grade cancers, although rest of clinico-pathological features did not show any gender difference. Mean follow-up of the study was 6-122 months with younger (< 29 years) patients reporting lower 5-year survival and higher stage disease. Renal cell carcinoma shows a different trend in our study population, compared to western data, with large size tumors and advanced stage presentation being more common.

Fibronectin protein expression in renal cell carcinoma in correlation with clinical stage of tumour

Background

Carcinogenesis is a multistep process which involves interplay between the tumour cells and the matrix proteins. This occurs by adherence between the tumour cells and proteins in the extracellular matrix. VHL mutation affects through the hypoxia inducible factor (HIF) and causes changes in various tissue proteins like VEGF, PDGF, TGF, Fibronectin and others. As not much literature is available, we aim to quantify the changes of fibronectin protein in renal cell carcinoma (RCC) tissue.

Methods

This Prospective unbalanced case control study was conducted over a period of 18 months from April 2016 to September 2017. The patients undergoing nephrectomy for the diagnosis of RCC were included in the study after obtaining written informed consent. Patients were excluded from study, if normal renal tissue could not be identified in the resected kidney and if the artery clamp time to retrieval of tissue was more than 30 min. Fibronectin protein is estimated in the tumour tissue by gel electrophoresis and western blotting which is compared with that of normal kidney tissue of the same kidney. Results have been expressed as absolute values with standard deviation and relative expression (RE).

Results

Of the 21 patients analysed 15 showed an increase in fibronectin expression in the renal tumour tissue while 6 did not. The mean expression of Fibronectin protein has increased 1.5 times in the tumour tissue when compared with the normal tissue. The increase was 1.54 times in early tumours compared to 1.37 times in advanced tumours of RCC.

Conclusions

Fibronectin showed a 1.5 times increase in the tumour compared to normal. This increase is more in Stage 1&2 tumours when compared to the Stage 3&4 tumours.

Electronic supplementary material

The online version of this article (10.1186/s40364-018-0137-8) contains supplementary material, which is available to authorized users.

Meta-analysis of gene expression and integrin-associated signaling pathways in papillary renal cell carcinoma subtypes

Papillary renal cell carcinoma (PRCC) is the second most common renal cell carcinoma (RCC) that can be further subdivided into type 1 (PRCC1) and type 2 (PRCC2) RCCs based on histological and genetic features. PRCC2 is often more aggressive than PRCC1. While integrin-associated protein complexes mediate tumorigenesis and metastases in many types of cancers it is not known whether integrin-mediated signaling impacts PRCC and differs between PRCC1 and PRCC2. In this study, we combined the analysis of five PRCC gene expression datasets derived from Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) by using integrative bioinformatics pipelines. We found 1475 differentially expressed genes among which 37 genes were associated with integrin pathways. In comparison with PRCC1, PRCC2 cases showed upregulated expression of α5-integrin (ITGA5) whereas the expression of α6- (ITGA6) and β8-integrins (ITGB8) was downregulated. Because PRCC2 occurs more frequently in men, the meta-analysis was extended to explore the gender effects. This analysis revealed 8 genes but none of them was related to integrin pathways suggesting that other mechanisms than integrin-mediated signaling underlie the observed gender differences in the pathogenicity of PRCC2.

Data-Independent Acquisition-Based Quantitative Proteomic Analysis Reveals Potential Biomarkers of Kidney Cancer

PURPOSE

Renal cell carcinoma (RCC) is a malignant and metastatic cancer with 95% mortality, and clear cell RCC (ccRCC) is the most observed among the five major subtypes of RCC. Specific biomarkers that can distinguish cancer tissues from adjacent normal tissues should be developed to diagnose this disease in early stages and conduct a reliable prognostic evaluation.

EXPERIMENTAL DESIGN

Data-independent acquisition (DIA) strategy has been widely employed in proteomic analysis because of various advantages, including enhanced protein coverage and reliable data acquisition. In this study, a DIA workflow is constructed on a quadrupole-Orbitrap LC-MS platform to reveal dysregulated proteins between ccRCC and adjacent normal tissues.

RESULTS

More than 4000 proteins are identified, 436 of these proteins are dysregulated in ccRCC tissues. Bioinformatic analysis reveals that multiple pathways and Gene Ontology items are strongly associated with ccRCC. The expression levels of L-lactate dehydrogenase A chain, annexin A4, nicotinamide N-methyltransferase, and perilipin-2 examined through RT-qPCR, Western blot, and immunohistochemistry confirm the validity of the proteomic analysis results.

CONCLUSIONS AND CLINICAL RELEVANCE

The proposed DIA workflow yields optimum time efficiency and data reliability and provides a good choice for proteomic analysis in biological and clinical studies, and these dysregulated proteins might be potential biomarkers for ccRCC diagnosis.

Androgen receptor (AR) suppresses miRNA-145 to promote renal cell carcinoma (RCC) progression independent of VHL status

Mutational inactivation of the VHL tumor suppressor plays key roles in the development of renal cell carcinoma (RCC), and mutated VHL-mediated VEGF induction has become the main target for the current RCC therapy. Here we identified a signal pathway of VEGF induction by androgen receptor (AR)/miRNA-145 as a new target to suppress RCC progression. Mechanism dissection revealed that AR might function through binding to the androgen receptor element (ARE) located on the promoter region of miRNA-145 to suppress p53's ability to induce expression of miRNA-145 that normally suppresses expression of HIF2α/VEGF/MMP9/CCND1. Suppressing AR with AR-shRNA or introducing exogenous miRNA-145 mimic can attenuate RCC progression independent of VHL status. MiR-145 mimic in preclinical RCC orthotopic xenograft mouse model revealed its efficacy in suppression of RCC progression. These results together identified signals by AR-suppressed miRNA-145 as a key player in the RCC progression via regulating HIF2α/VEGF/MMP9/CCND1 expression levels. Blockade of the newly identified signal by AR inhibition or miRNA-145 mimics has promising therapeutic benefit to suppress RCC progression.

Diagnostic utility of vimentin, CD117, cytokeratin-7 and caveolin-1 in differentiation between clear cell renal cell carcinoma, chromophobe renal cell carcinoma and oncocytoma

Overlapping morphological characteristics pose some difficulties in making a proper diagnosis of clear cell renal cell carcinoma (CCRCC), chromophobe renal cell carcinoma (ChRCC), and oncocytoma, on the basis of hematoxylin-eosin-stained tissue sections. Our objective was to find out a fast, reliable panel of immunohistochemical markers for differentiation between them. The study was carried out on 55 selected renal tumor specimens: 36 cases of CCRCC, seven cases of ChRCC, and 12 cases of oncocytoma. The specimens were stained immunohistochemically for vimentin, CD117, cytokeratin (CK)7, and caveolin (Cav)-1. Sensitivity and specificity for each marker were calculated. Vimentin expression was exclusively observed in CCRCC (100%) and negative in ChRCC and oncocytoma. CD117 was absent in CCRCC, but it was strongly expressed in ChRCC (85.5%) and oncocytoma (91.7%), with high sensitivity and specificity. Most CCRCCs and oncocytomas were negative for CK7 (91.7% and 83.3%, respectively), in contrast to ChRCCs, which showed positivity in nearly 86% of the cases. Good sensitivity and specificity were calculated for CK7 in differentiating studied oncocytic tumors. Cav-1 was positive in ~78% of the CCRCCs and in all ChRCCs, whereas the vast majority of oncocytomas were negative. So the immunoprofile of CCRCC was vimentin⁺/CD117^-/CK7^-/Cav-1^±, ChRCC was vimentin^-/CD117⁺/CK7⁺/Cav-1⁺, and oncocytoma was vimentin^-/CD117⁺/CK7^±/Cav-1^-. So, by using combination of four markers (vimentin, CD117, CK7, and Cav-1), we achieved excellent sensitivity and specificity for differential diagnosis of CCRCC, ChRCC and oncocytoma.

Pseudogene PTENP1 functions as a competing endogenous RNA to suppress clear-cell renal cell carcinoma progression

PTENP1 is a pseudogene of the PTEN tumor suppression gene (TSG). The functions of PTENP1 in clear-cell renal cell carcinoma (ccRCC) have not yet been studied. We found that PTENP1 is downregulated in ccRCC tissues and cells due to methylation. PTENP1 and PTEN are direct targets of miRNA miR21 and their expression is suppressed by miR21 in ccRCC cell lines. miR21 expression promotes ccRCC cell proliferation, migration, invasion in vitro, and tumor growth and metastasis in vivo. Overexpression of PTENP1 in cells expressing miR21 reduces cell proliferation, invasion, tumor growth, and metastasis, recapitulating the phenotypes induced by PTEN expression. Overexpression of PTENP1 in ccRCC cells sensitizes these cells to cisplatin and gemcitabine treatments in vitro and in vivo. In clinical samples, the expression of PTENP1 and PTEN is correlated, and both expressions are inversely correlated with miR21 expression. Patients with ccRCC with no PTENP1 expression have a lower survival rate. These results suggest that PTENP1 functions as a competing endogenous RNA (ceRNA) in ccRCC to suppress cancer progression.

ASC-J9 suppresses renal cell carcinoma progression by targeting an androgen receptor-dependent HIF2α/VEGF signaling pathway

Males have a higher incidence of renal cell carcinoma (RCC) than females, but the reason for this gender difference is unknown. Addressing this question, we report the discovery of an androgen receptor (AR)-induced HIF2α/VEGF signal that drives RCC progression. AR attenuation or augmentation in RCC cells altered their proliferation, migration, and invasion in multiple models in vitro and in vivo. Mechanistic investigations revealed that AR targeting inhibited RCC cell migration and invasion by modulating HIF2α/VEGF signals at the level of mRNA and protein expression. Interrupting HIF2α/VEGF signals with inhibitors of either HIF2α or VEGF was sufficient to suppress RCC progression. Similarly, the specific AR degradation enhancer ASC-J9 was sufficient to suppress AR-induced HIF2α/VEGF signaling and RCC progression in multiple models in vitro and in vivo. Taken together, our results revealed a novel role for AR in RCC initiation and progression with implications for novel therapeutic strategies.

Race and sex disparities in the treatment of older patients with T1a renal cell carcinoma: a comorbidity-controlled competing-risks model

OBJECTIVES

Recognizing population-level disparities for the treatment of patients with renal cell carcinoma (RCC) would inform clinical practice and health policy. Few studies, reporting conflicting results, have investigated race and sex disparities specifically among patients with small renal masses.

METHODS AND MATERIALS

The Surveillance, Epidemiology, and End Results-Medicare database (1995-2007) was queried for patients with localized T1a RCC undergoing radical nephrectomy, partial nephrectomy (PN), or deferred therapy (DT). Demographics, comorbidity, and treatment approach were assessed. Multivariable logistic regression models evaluated predictors of DT and then PN among those receiving surgery. Cox proportional hazards model evaluated survival differences for whites vs. blacks and women vs. men.

RESULTS

A total of 6,092 white and 617 black patients with T1a RCC met the inclusion criteria. Blacks were twice as likely to defer therapy compared with whites (odds ratio = 1.95, 95% CI: 1.52-2.51) and had worse overall survival (hazard ratio = 1.36, 95% CI: 1.19-1.56). However, cancer-specific survival (CSS) was similar (P = 0.429). The greatest discrepancy was among healthy (Charlson comorbidity index≤1) blacks who had a much higher rate of DT compared with their white counterparts. Women were found to have decreased use of PN compared with men (odds ratio = 0.84, 95% CI: 0.74-0.96) and better CSS (hazard ratio = 0.74, 95% CI: 0.58-0.94), but there were no differences by race.

CONCLUSIONS

The differential use of DT by race instead of purely by age and comorbidity is concerning but has not led to a significant difference in CSS. Women are less likely to undergo PN compared with men, but they also have a notably improved CSS.

Gender differences in clinicopathological features and survival in surgically treated patients with renal cell carcinoma: an analysis of the multicenter CORONA database

PURPOSE

To investigate gender differences in clinicopathological features and to analyze the prognostic impact of gender in renal cell carcinoma (RCC) patients undergoing surgery.

METHODS

A total of 6,234 patients (eleven centers; Europe and USA) treated by radical or partial nephrectomy were included in this retrospective study (median follow-up 59 months; IQR 30-106). Gender differences in clinicopathological parameters were assessed. Multivariable Cox regression models were applied to determine the influence of parameters on disease-specific survival (DSS) and overall survival (OS).

RESULTS

A total of 3,751 patients of the study group were male patients (60.2 %), who were significantly younger at diagnosis and received more frequently NSS than women. Significantly, more often high-grade tumors and simultaneous metastasis were present in men. Whereas tumor size and pTN stages did not differ between genders, clear-cell and chromophobe RCC was diagnosed less frequently, but papillary RCC more often in men. Gender also independently influenced DSS (HR 0.75, p < 0.001) and OS (HR 0.80, p < 0.001) with a benefit for women. However, inclusion of gender in multivariable models did not significantly gain predictive accuracies (PA) for DSS (0.868-0.870, p = 0.628) and OS (0.775-0.777, p = 0.522). Furthermore, no significantly different DSS and OS rates were found in patients undergoing NSS.

CONCLUSIONS

This study demonstrates important gender differences in clinicopathological features and outcome of RCC patients with improved DSS and OS for women compared to men, even if solely patients with clear-cell RCC or M0-stage are taken into evaluation. However, inclusion of gender in multivariable models does not significantly gain PA of multivariable models.

High expression of FER tyrosine kinase predicts poor prognosis in clear cell renal cell carcinoma

FER tyrosine kinase (FER) has been demonstrated to play a critical role in tumorigenesis and metastasis; however, its potential value as a novel prognostic marker for clear cell renal cell carcinoma (ccRCC) remains unclear. In 48 paired samples of ccRCCs and normal adjacent tissues (ADTs), real-time PCR was used to evaluate the expression of FER mRNA. The expression of FER protein was assessed in 87 ADTs and 206 samples of ccRCC using immunohistochemical methods. Statistical analysis was used to examine the correlations between the expression levels of FER and the clinical characteristics of ccRCC patients. A significant difference was identified between ccRCC tissues and ADTs in the mRNA levels of FER. Immunohistochemistry analyses revealed higher expression of FER protein in 87 ccRCC samples compared to the paired ADTs. In addition, FER protein expression in 206 ccRCC samples was significantly correlated with tumor size, T stage, N classification, metastasis, recurrence and Fuhrman grade, while associations with age and gender were not identifed. The Kaplan-Meier survival analysis showed that patients with high FER levels had a poorer survival outcome compared with those with lower levels. The log-rank test demonstrated that the cumulative survival rates were significantly different between the two groups. The Cox regression analysis indicated that FER expression, N stage and distant metastasis were independent prognostic factors for overall survival of ccRCC patients. Our results indicate that overexpression of FER in tumor tissues predicts a poor prognosis of patients with ccRCC, and FER may serve as a novel prognostic marker for ccRCC.

Fibronectin 1 protein expression in clear cell renal cell carcinoma

Fibronectin 1 (FN1) is a glycoprotein that is involved in cell adhesion and migration processes including embryogenesis, wound healing, blood coagulation, host defenses and metastasis. The aim of this study was to elucidate the FN1 protein expression in renal cell carcinoma (RCC) and to determine its potential prognostic relevance. A total of 270 clear cell RCC tissue specimens were collected from patients undergoing surgery for renal tumors. Biomarker expression was determined by immunohistochemistry and correlated with clinical variables. Survival analysis was carried out for 153 patients with complete follow-up data and pathologically proven clear cell carcinoma of the kidney. The follow-up group had a mean follow-up period of 83.8 months (IQR 26.2-136.2 months). The calculated median 5-year overall and tumor-specific survival rate of all 153 evaluable patients was 66.6 and 71.0%, respectively. A higher disease-related mortality rate was observed among patients with cytoplasmic FN1 expression (41.3 vs. 24.7%, p=0.039, Fisher's exact test). No significant correlation was found between FN1 staining and patient characteristics such as age, gender, tumor differentiation and visceral metastasis. However, there was a trend for FN1 expression and correlation with tumor stage and lymph node metastasis (p=0.085 and p=0.203; respectively). The Kaplan-Meier analysis revealed significant differences in the 5-year tumor-specific survival for patients with and without cytoplasmic FN1 expression (64.8 vs. 77.7%; p=0.035, log-rank test). However, results of the multivariate Cox regression analysis showed that FN1 expression was not an independent marker of either overall or tumor-specific survival. In conclusion, FN1 protein expression in RCC is associated with a higher disease-related mortality rate, indicating a possible role in RCC progression. Therefore, our data on FN1 encourage further investigations to determine the role of FN1 in RCC.

Caveolin 1 protein expression in renal cell carcinoma predicts survival

Background

Caveolae play a significant role in disease phenotypes such as cancer, diabetes, bladder dysfunction, and muscular dystrophy. The aim of this study was to elucidate the caveolin-1 (CAV1) protein expression in renal cell cancer (RCC) and to determine its potential prognostic relevance.

Methods

289 clear cell RCC tissue specimens were collected from patients undergoing surgery for renal tumors. Both cytoplasmic and membranous CAV1 expression were determined by immunohistochemistry and correlated with clinical variables. Survival analysis was carried out for 169 evaluable patients with a median follow up of 80.5 months (interquartile range (IQR), 24.5 - 131.7 months).

Results

A high CAV1 expression in the tumor cell cytoplasm was significantly associated with male sex (p = 0.04), a positive nodal status (p = 0.04), and poor tumor differentiation (p = 0.04). In contrast, a higher than average (i.e. > median) CAV1 expression in tumor cell membranes was only linked to male sex (p = 0.03). Kaplan-Meier analysis disclosed significant differences in 5-year overall (51.4 vs. 75.2%, p = 0.001) and tumor specific survival (55.3 vs. 80.1%, p = 0.001) for patients with higher and lower than average cytoplasmic CAV1 expression levels, respectively. Applying multivariable Cox regression analysis a high CAV1 protein expression level in the tumor cell cytoplasm could be identified as an independent poor prognostic marker of both overall (p = 0.02) and tumor specific survival (p = 0.03) in clear cell RCC patients.

Conclusion

Over expression of caveolin-1 in the tumour cell cytoplasm predicts a poor prognosis of patients with clear cell RCC. CAV1 is likely to be a useful prognostic marker and may play an important role in tumour progression. Therefore, our data encourage further investigations to enlighten the role of CAV1 and its function as diagnostic and prognostic marker in serum and/or urine of RCC patients.

Gender-specific clinicopathological features and survival in patients with renal cell carcinoma (RCC)

There has been some controversy about the gender differences in survival in patients with RCC. Korean women with RCC had a lower proportion of clear cell histology and a higher proportion of chromophobe histology. This histological difference might have driven the better survival rates in Korean women.

OBJECTIVE

To assess whether there are gender-specific differences in the clinicopathological features and prognosis in a large cohort of Korean patients with renal cell carcinoma (RCC) compared with Western patients.

PATIENTS AND METHODS

Medical records of 1616 patients clinically diagnosed with RCC who underwent partial or radical nephrectomy were analysed between January 1988 and July 2009. In all, 1508 patients diagnosed with RCC based on pathology reports were included for evaluation. The mean follow-up period was 73.1 months. The gender-specific differences in the clinicopathological features and survival rates were evaluated using the Kaplan-Meier method and Cox proportional hazards models.

RESULTS

Of the 1508 patients, 439 (29.1%) were women. Korean men had a higher proportion of clear cell histology (84.3% vs 72.0%, P < 0.001) and a lower percentage of chromophobe histology (5.2% vs 12.5%, P < 0.001) than Korean women. There were no gender-specific differences in pathological T stage, positive lymph nodes or distant metastases, or Fuhrman's nuclear grade (P > 0.05). For both cancer-specific and overall survival, Kaplan-Meier curves showed that women had a better survival rate than men (P = 0.039 and P = 0.015, respectively).

CONCLUSIONS

Korean women with RCC had significantly better survival rates than Korean men. Additionally, Korean women with RCC had a lower proportion of clear cell histology and a higher proportion of chromophobe histology. This histological difference might have driven the better survival rates in Korean women.

Meta-analysis of clear cell renal cell carcinoma gene expression defines a variant subgroup and identifies gender influences on tumor biology

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) displays molecular and histologic heterogeneity. Previously described subsets of this disease, ccA and ccB, were defined based on multigene expression profiles, but it is unclear whether these subgroupings reflect the full spectrum of disease or how these molecular subtypes relate to histologic descriptions or gender.

OBJECTIVE

Determine whether additional subtypes of ccRCC exist and whether these subtypes are related to von Hippel-Lindau (VHL) inactivation, hypoxia-inducible factor (HIF) 1 and 2 expression, tumor histology, or gender.

DESIGN, SETTING, AND PARTICIPANTS

Six large, publicly available ccRCC gene expression databases were identified that cumulatively provided data for 480 tumors for meta-analysis via meta-array compilation.

MEASUREMENTS

Unsupervised consensus clustering was performed on the meta-arrays. Tumors were examined for the relationship of multigene-defined consensus subtypes and expression signatures of VHL mutation and HIF status, tumor histology, and gender.

RESULTS AND LIMITATIONS

Two dominant subsets of ccRCC were observed. However, a minor third cluster was revealed that correlated strongly with a wild type (WT) VHL expression profile and indications of variant histologies. When variant histologies were removed, ccA tumors naturally divided by gender. This technique is limited by the potential for persistent batch effect, tumor sampling bias, and restrictions of annotated information.

CONCLUSIONS

The ccA and ccB subsets of ccRCC are robust in meta-analysis among histologically conventional ccRCC tumors. A third group of tumors was identified that may represent a new variant of ccRCC. Within definitively clear cell tumors, gender may delineate tumors in such a way that it could have implications regarding current treatments and future drug development.

Caveolin 1 mRNA is overexpressed in malignant renal tissue and might serve as a novel diagnostic marker for renal cancer

Background & aim: Caveolae play a significant role in disease phenotypes, such as cancer, diabetes, bladder dysfunction and muscular dystrophy. The aim of this study was to elucidate the expression of caveolin (CAV)1 in the development of renal cell cancer (RCC) and to determine a possible prognostic relevance for optimal clinical management. Material & methods: 109 RCC and 81 corresponding normal tissue specimens from the same kidney were collected from patients undergoing surgery for renal tumors and subjected to total RNA extraction. Quantification of CAV1 mRNA expression was performed using real-time reverse transcription PCR with three endogenous controls for renal proximal tubular epithelial cells and the ΔΔCt method for calculation of relative quantities. Expression levels were correlated to clinical variables. Results: Tissue-specific mean CAV1 expression was significantly increased in RCC compared with normal renal tissue (p = 0.0003; paired Wilcoxon rank sum test). CAV1 expression was increased 1.9-fold in clear cell RCC compared with papillary RCC (p = 1.48 × 10–7; unpaired Wilcoxon rank sum test). Patients with advanced disease had higher CAV1 expression when compared with organ-confined disease (p = 0.019; unpaired Wilcoxon rank sum test). Moreover, mean tissue-specific CAV1 expression was increased in patients with distant metastasis at the time of diagnosis compared with patients without metastasis (p = 0.0058; unpaired Wilcoxon rank sum test). Conclusion: To our knowledge, this is the first study to show that CAV1 mRNA expression, using quantitative real-time PCR, is significantly higher in RCC compared with normal renal tissue and increases with tumor stage. CAV1 mRNA expression might serve as a candidate biomarker for objective prognosis indicating RCC aggressiveness. Our data encourage further investigations to determine the role of CAV1 in RCC.

Does male sex influence the prognosis of patients with renal cancer?

BACKGROUND

The aim of this study was to investigate the influence of sex on stage, grade, subtype, and prognosis of patients with renal cell carcinoma (RCC).

PATIENTS AND METHODS

This study included 1,810 patients treated by surgery for RCC at the University Hospitals of Hannover and Marburg between 1990 and 2005. The median follow-up was 54 months.

RESULTS

Of all the patients, 1,167 (64.5%) were men and 643 (35.5%) were women. Men were significantly younger (mean, 61.4 vs. 63.5 years; p < 0.001), and suffered more frequently from advanced tumor stages (45.2 vs. 37.6%; p = 0.002) and higher tumor grades (14.1 vs. 11.1%; p = 0.003). Kaplan Meier curves revealed a significant difference in cancer-specific survival between men and women (5-year survival 64.7 vs. 74.0%; p = 0.002). However, unlike tumor stage, grade, and N/M status, sex could not be retained as a significant independent prognostic marker in multivariate analysis.

CONCLUSIONS

RCC in men is characterized by higher tumor stages and more frequent metastasis at diagnosis along with inferior tumor-specific survival. However, as sex failed to qualify as an independent prognostic marker for cancer-specific survival, delayed diagnosis due to insufficient or neglected (routine) medical check-up and/or more aggressive tumor biology could be concurrently causative for the higher incidence of RCC in men.

Fibronectin 1 mRNA expression correlates with advanced disease in renal cancer

Background

Fibronectin 1 (FN1) is a glycoprotein involved in cellular adhesion and migration processes. The aim of this study was to elucidate the role of FN1 in development of renal cell cancer (RCC) and to determine a prognostic relevance for optimal clinical management.

Methods

212 renal tissue samples (109 RCC, 86 corresponding tissues from adjacent normal renal tissue and 17 oncocytomas) were collected from patients undergoing surgery for renal tumors and subjected to total RNA extraction. Detection of FN1 mRNA expression was performed using quantitative real time PCR, three endogenous controls, renal proximal tubular epithelial cells (RPTEC) as biological control and the ΔΔCt method for calculation of relative quantities.

Results

Mean tissue specific FN1 mRNA expression was found to be increased approximately seven fold comparing RCC and corresponding kidney control tissues (p < 0.001; ANOVA). Furthermore, tissue specific mean FN1 expression was increased approx. 11 fold in clear cell compared to papillary RCC (p = 9×10^-5; Wilcoxon rank sum test). Patients with advanced disease had higher FN1 expression when compared to organ-confined disease (p < 0.001; Wilcoxon rank sum test). Applying subgroup analysis we found a significantly higher FN1 mRNA expression between organ-confined and advanced disease in the papillary and not in the clear cell RCC group (p = 0.02 vs. p = 0.2; Wilcoxon rank sum test). There was an increased expression in RCC compared to oncocytoma (p = 0.016; ANOVA).

Conclusions

To our knowledge, this is the first study to show that FN1 mRNA expression is higher in RCC compared to normal renal tissue. FN1 mRNA expression might serve as a marker for RCC aggressiveness, indicating early systemic progression particularly for patients with papillary RCC.

The clinical characteristics of renal cell carcinoma in female patients

OBJECTIVE

To investigate the clinical characteristics of renal cell carcinoma (RCC) in female patients.

METHODS

The clinical characteristics including sex, age at diagnosis, histological tumor size, histological subtype, Fuhrman nuclear grade and pathological tumor-node-metastasis (TNM) stage of 881 consecutive patients treated with (partial) nephrectomy for RCC from 1998 to 2006 were analyzed. Characteristics of different gender groups and different female age groups were compared. The one-way anova and t-test were used to compare means. Pearson's chi(2)-test and the likelihood ratio test were used to compare ratios.

RESULTS

Low-grade tumors accounted for 79.3% of female patients and 64.1% of male patients (P < 0.001). The percentage of stage T1-2 was 76.6% in female patients while it was only 68.5% in male patients (P = 0.011). Also, female patients had more T1-2N0M0 tumors (73.0% vs 64.3%, P = 0.009). Once female patients were classified into three groups according to age diagnosis (<or=40, 41-59 and >or=60 years) young female patients seemed to have more tumors with unfavorable histology (8.7% vs 5.1% vs 4.3%), Fuhrman grade 3-4 (23.9% vs 23.1% vs 17.7%) and stage T3-4 (28.3% vs 23.1% vs 22.0%).

CONCLUSION

Compared with male patients, female patients had lower stage and grade tumors. However, younger female patients had more tumors with unfavorable histology, and higher stage and grade compared to older female patients.