Sex specific associations in genome wide association analysis of renal cell carcinoma

Renal cell carcinoma (RCC) has an undisputed genetic component and a stable 2:1 male to female sex ratio in its incidence across populations, suggesting possible sexual dimorphism in its genetic susceptibility. We conducted the first sex-specific genome-wide association analysis of RCC for men (3227 cases, 4916 controls) and women (1992 cases, 3095 controls) of European ancestry from two RCC genome-wide scans and replicated the top findings using an additional series of men (2261 cases, 5852 controls) and women (1399 cases, 1575 controls) from two independent cohorts of European origin. Our study confirmed sex-specific associations for two known RCC risk loci at 14q24.2 (DPF3) and 2p21(EPAS1). We also identified two additional suggestive male-specific loci at 6q24.3 (SAMD5, male odds ratio (ORmale) = 0.83 [95% CI = 0.78-0.89], Pmale = 1.71 × 10-8 compared with female odds ratio (ORfemale) = 0.98 [95% CI = 0.90-1.07], Pfemale = 0.68) and 12q23.3 (intergenic, ORmale = 0.75 [95% CI = 0.68-0.83], Pmale = 1.59 × 10-8 compared with ORfemale = 0.93 [95% CI = 0.82-1.06], Pfemale = 0.21) that attained genome-wide significance in the joint meta-analysis. Herein, we provide evidence of sex-specific associations in RCC genetic susceptibility and advocate the necessity of larger genetic and genomic studies to unravel the endogenous causes of sex bias in sexually dimorphic traits and diseases like RCC.

Cyclin D1 and p57 expression in relation to clinicopathological characteristics and overall survival in patients with renal cell carcinoma

PURPOSE

There is a need for identifying molecular prognostic biomarkers to better predict clinical outcomes in patients with renal cell carcinoma (RCC). This study investigated the pattern of cyclin D1 and p57 expression in RCC patients and evaluated their relation with clinicopathological characteristics and overall survival (OS).

METHODS

Immunohistochemistry was applied to paraffin-embedded tissue sections of 74 RCC patients. Two cut-off groups were defined by the fraction of positive cells as follows: ≤10% and >10% positive cells for cyclin D1, and ≤5% and >5% positive cells for p57.

RESULTS

Cyclin D1 expression in >10% of positive cells was observed mostly in the clear cell RCC, while p57 expression in ≤5% of positive cells was found in 86% of chromophobe RCC specimens. The higher expression of cyclin D1 and lower expression of p57 were more frequent in grade I-II tumors. OS was associated with unfavorable clinicopathological characteristics. However, cyclin D1/p57 expression did not influence the survival rates.

CONCLUSION

Although cyclin D1 and p57 expression did not affect survival rates in RCC patients, proper validation and establishment of the qualitative cut-off point are needed for these tumors.

The influence of obesity-related factors in the etiology of renal cell carcinoma-A mendelian randomization study

BACKGROUND

Several obesity-related factors have been associated with renal cell carcinoma (RCC), but it is unclear which individual factors directly influence risk. We addressed this question using genetic markers as proxies for putative risk factors and evaluated their relation to RCC risk in a mendelian randomization (MR) framework. This methodology limits bias due to confounding and is not affected by reverse causation.

METHODS AND FINDINGS

Genetic markers associated with obesity measures, blood pressure, lipids, type 2 diabetes, insulin, and glucose were initially identified as instrumental variables, and their association with RCC risk was subsequently evaluated in a genome-wide association study (GWAS) of 10,784 RCC patients and 20,406 control participants in a 2-sample MR framework. The effect on RCC risk was estimated by calculating odds ratios (ORSD) for a standard deviation (SD) increment in each risk factor. The MR analysis indicated that higher body mass index increases the risk of RCC (ORSD: 1.56, 95% confidence interval [CI] 1.44-1.70), with comparable results for waist-to-hip ratio (ORSD: 1.63, 95% CI 1.40-1.90) and body fat percentage (ORSD: 1.66, 95% CI 1.44-1.90). This analysis further indicated that higher fasting insulin (ORSD: 1.82, 95% CI 1.30-2.55) and diastolic blood pressure (DBP; ORSD: 1.28, 95% CI 1.11-1.47), but not systolic blood pressure (ORSD: 0.98, 95% CI 0.84-1.14), increase the risk for RCC. No association with RCC risk was seen for lipids, overall type 2 diabetes, or fasting glucose.

CONCLUSIONS

This study provides novel evidence for an etiological role of insulin in RCC, as well as confirmatory evidence that obesity and DBP influence RCC risk.

Immunohistochemical expression of proliferative markers in renal cell carcinoma

PURPOSE

The purpose of this study was to investigate into the expression of cyclin A and telomerase in renal cell carcinoma (RCC) and to analyze the relationship between expression and the clinicopathological characteristics of the tumor and their impact on survival.

METHODS

The overall material included 74 samples of RCC and 4 of normal renal tissue. Primary cyclin A antibody from Santa Cruz Biotechnology and TERT MA5-16034 antibody from Thermo Fisher Scientific Inc were used. Staining was performed by streptavidin-biotin technique using DAKO LSAB+ kit. Statistical analyses were performed using of SPSS 23 Statistics software from IBM.

RESULTS

No differences in cyclin A and telomerase expression among gender and age groups were found, nor did the tumor dimensions have any significant impact on expression. Also, tumor grades and stages did not differ. However, histological types differed in favor of the papillary type. A significant positive correlation between both markers, as well as between the expression and tumor stage and grade was noticed. Only the tumor stage had negative impact on survival.

CONCLUSIONS

Although not affecting survival, the expression of cyclin A and telomerase increased with tumor stage and grade, suggesting that cyclin A and telomerase could be potential proliferative immunohistochemical markers of RCC.

Clinicopathological characteristics and survival in Serbian patients with renal cell carcinoma: a retrospective analysis

PURPOSE

Indications of kidney cancer outcome in lowerincome countries are based on an incidence/mortality ratio due to lack of survival information. This study was conducted to provide outcome data in Serbian patients with renal cell carcinoma (RCC) and to identify prognostic factors that could affect their overall survival (OS).

METHODS

This retrospective study included 185 patients who underwent nephrectomy. We assessed certain clinicopathological data including age, gender, tumor size, grade, stage and histological subtypes for their possible impact on OS.

RESULTS

The 5-year OS was 63.2%. Significant association was found between OS and age (log-rank 12.455, p=0.006), tumor size (log-rank 26.425, p=0.000), grade (log-rank 13.249, p=0.000) and stage (log-rank 43.235, p=0.000). Univariate analysis indicated size (p=0.000), grade (p=0.001) and stage (p=0.000) as prognostic factors for OS. In multivariate analysis, grade (p=0.014) and stage (p=0.000) remained significant predictors of OS.

CONCLUSION

Tumor grade and stage were identified as independent prognostic factors of OS survival in Serbian patients with RCC.

Immunohistochemical study of cyclin A and p16 expression in patients with renal cell carcinoma

PURPOSE

Renal cell carcinoma (RCC) is the most common malignant kidney tumor in adults. Dysregulation of the cell cycle can lead to cancer development. In this study, the mitosis-associated cyclin A and p16, a negative controller, were investigated as potential key points in the RCC development.

METHODS

This retrospective study included 74 patients with RCC. The expression of cyclin A and p16 and their correlation to histopathological parameters (TNM stage, histological subtype, nuclear grade, tumor size), gender, age, and clinical outcome were studied and analyzed.

RESULTS

The highest median value for cyclin A (40%; range 0-70)) and for p16 (57.5%); range 35-80) were found in the papillary histological subtype. Survival analysis showed that in the group of patients that had died before September 2015, the median value for cyclin A was 20% (range 0-60), which was significantly higher than 5% (range 0-70), found in the group of patients that survived (p=0.019).

CONCLUSIONS

In relation to the histological subtype, the papillary type of RCC was associated with a significantly higher expression of cyclin A and p16 compared to other subtypes of RCC. High expression of cyclin A indicated worse prognosis, therefore cyclin A could be considered to be a significant prognostic marker.

Acute Renal Failure in Different Malignant Tumors

Acute renal failure (ARF) represents a severe complication of malignancies, that causes significant morbidity and mortality. ARF is a common part of multiple organ dysfunction in critically ill patients with cancer with reported mortality rates from 72% to 85% in patients who need renal replacement therapy. The pathways leading to ARF in cancer patients are common to the development of ARF in other conditions. However, certain factors leading to the development of ARF may be associated to the tumor or to the tumor therapy. The purpose of this review is to give specific aspects of renal disease in critically ill cancer patients (CICPs), to overview the causes of ARF in CICPs and to describe recent progress in the management of these complications, including treatment toxicity and bone marrow transplantation (BMT). The prevention of ARF is obligatory and therefore the possible treatments of ARF in CICPs are also discussed.

Acute Renal Failure - A Serious Complication in Patients After Kidney Transplantation

Free radical-mediated injury releases proinflammatory cytokines and activates innate immunity. It has been suggested that the early innate response and the ischemic tissue damage play roles in the development of adaptive responses, which may lead to acute kidney rejection. Various durations of hypothermic kidney storage before transplantation add to ischemic tissue damage. The final stage of ischemic injury occurs during reperfusion that develops hours or days after the initial insult. Repair and regeneration processes occur together with cellular apoptosis, autophagy and necrosis and a favorable outcome is expected if regeneration prevails. Along the entire transplantation time course, there is a great demand for novel immune and nonimmune injury biomarkers. The use of these markers can be of great help in the monitoring of kidney injury in potential kidney donors, where acute kidney damage can be overlooked, in predicting acute transplant dysfunction during the early post-transplant periods, or in predicting chronic changes in long term followup. Numerous investigations have demonstrated that biomarkers that have the highest predictive value in acute kidney injury include NGAL, Cystatin C, KIM-1, IL-18, and L-FABP. Most investigations show that the ideal biomarker to fulfill all the needs in renal transplant has not been identified yet. Although, in many animal models, new biomarkers are emerging for predicting acute and chronic allograft damage, in human allograft analysis they are still not routinely accepted and renal biopsy still remains the gold standard.

Polymorphisms of survivin -31 G/C gene are associated with risk of urothelial carcinoma in Serbian population

PURPOSE

Survivin is thought to play an important role in carcinogenesis and is found to be associated with poor clinical outcome in various malignancies. Gene -31 G/C polymorphism has been identified as a risk factor for the development of several types of tumors. The purpose of this study was to investigate the association between survivin gene promoter -31C/G polymorphism and urothelial carcinoma (UC) risk in Serbian population and to compare the different expressions of survivin in UC of different disease stages, histological grades and tumor location in the upper or lower urinary tract.

METHODS

DNA from 94 patients with primary UC and from 82 healthy subjects was subjected to PCR restriction fragment length polymorphism analysis (PCR-RFLP) to identify individual genotypes. UC samples were subjected to immunohistochemical analysis to assess survivin expression in these lesions.

RESULTS

It was observed that the frequency of G/G genotype was greater in patients with UC (58.7%) than in controls (32%). Compared with study subjects carrying the C/G or C/C genotypes, significantly increased UC risk was found for individuals carrying the G/G genotype. Those carrying the G/G genotype had a significantly increased UC risk compared with those with C/G or C/C genotypes. Patients with UC carrying the G/G genotype had a greater prevalence of muscle-invading (stage T2-T4), high-grade (G2) tumor and immunohistochemicaly overexpressed survivin compared with those carrying the C/G or C/C genotypes.

CONCLUSIONS

G/G genotype of the -31C/G polymorphism might be a risk factor for UC development.

Cytomegalovirus induces Interleukin-6 mediated inflammatory response in salivary gland cancer

PURPOSE

The purpose of this study was to examine whether cytomegalovirus (CMV) is present in different histological types of salivary gland cancer (SGC) by detecting CMV immediate-early (IE) and early gene products, and to determine the presence of its association with the overexpression of interleukin (IL)-6.

METHODS

Immunohistochemical analysis of 92 cases of different histological types of SGC was performed to determine the presence of IL-6 and CMV antigen and its intensity in tumor tissue. Twenty samples of normal salivary gland tissue obtained during autopsy served as healthy controls.

RESULTS

CMV antigens were not found in healthy acinar tissue of salivary glands, but were expressed in epithelium of salivary gland ducts. Negative expression of CMV antigens was also found in salivary gland tissue surrounding tumors. On the other hand, CMV was detected in 65/92 SGC cases (70.6%). Higher expression of IL-6 was found in SGC (70.7%) than in normal tissue (20%). There was a high association of CMV antigen presence with the presence of IL-6, and with the IL-6 expression intensity.

CONCLUSIONS

Positive expression of CMV antigens in a high percentage of SGC cells suggests that it might play an important role in carcinogenesis by increasing IL-6 production and leading to inhibition of apoptosis and tumor development.

Acute Renal Failure in Transplanted Kidneys

Free radical-mediated injury releases proinflammatory cytokines and activates innate immunity. It has been suggested that the early innate response and the ischemic tissue damage play roles in the development of adaptive responses, which may lead to acute kidney rejection. Various durations of hypothermic kidney storage before transplantation add to ischemic tissue damage. The final stage of ischemic injury occurs during reperfusion that develops hours or days after the initial insult. Repair and regeneration processes occur together with cellular apoptosis, autophagy and necrosis and a favorable outcome is expected if regeneration prevails. Along the entire transplantation time course, there is a great demand for novel immune and nonimmune injury biomarkers. The use of these markers can be of great help in the monitoring of kidney injury in potential kidney donors, where acute kidney damage can be overlooked, in predicting acute transplant dysfunction during the early post-transplant periods, or in predicting chronic changes in long term followup. Numerous investigations have demonstrated that biomarkers that have the highest predictive value in acute kidney injury include NGAL, Cystatin C, KIM-1, IL-18, and L-FABP. Most investigations show that the ideal biomarker to fulfill all the needs in renal transplant has not been identified yet. Although, in many animal models, new biomarkers are emerging for predicting acute and chronic allograft damage, in human allograft analysis they are still not routinely accepted and renal biopsy still remains the gold standard.

Prognostic value of survivin expression in Wilms tumor

PURPOSE

To determine survivin expression patterns in Wilms tumor (WT) and compare it with the expression in normal renal tissue. Also, to analyse cytoplasmic and nuclear survivin expression in relation to histological type, prognostic group and tumor stage.

METHODS

Immunohistochemical expression of survivin was analysed in 59 cases of primary WT and in 10 normal kidney specimens, taken from the same patients, but distant from the tumor.

RESULTS

51 out of 59 cases of WT (86.44%) showed decreased cytoplasmic survivin expression and 4 out of 59 cases of WT (6.78%) showed nuclear overexpression of survivin. There was statistically significant difference in the frequency of decreased cytoplasmic expression of survivin in individual components of WT (p=0.005). Decreased cytoplasmic expression of survivin in epithelial, blastemal and stromal component was found significantly more often in low stage WT compared to high stage WT (Fisher exact test, p=0.0002, p=0.002, p=0.002, respectively). There was no statistically significant difference in the frequency of survivin nuclear overexpression between different stages of WT (Fisher exact test, p=0.564), histological types (Fisher exact test, p=0.915), or between different prognostic groups (Fisher exact test, p=1).

CONCLUSION

Decreased survivin cytoplasmic expression or nuclear overexpression may be related to favorable prognosis of WT.

Immunohistochemical detection of cyclin E in transitional cell carcinoma

PURPOSE

It is known that expression disorders of cell cycle regulators play an important role in the development and prognosis of various malignant tumors. Cyclin expression changes during the cell cycle. This work aimed to analyse the expression of cyclin E in transitional cell carcinoma (TCC) and also to compare the expression of cyclin E with tumor stage and histological grade as well as to determine possible existence of differences in the expression of cyclin E in TCCs of the upper and lower urothelium.

METHODS

Twenty-four cases of TCC of the urinary tract were retrospectively analysed (6 cancers of the renal pelvis, 2 of the ureter and 15 of the bladder; 4 were infiltrative). Immunohistochemical staining for cyclin E of the analysed transitional cancer cells was assessed semiquantitatively: diffuse cyclin E expression + + + (> 50% of all cells), expression in larger groups of cells: + + (up to 50% of all cells), expression in individual cells or small cell clusters: + (<10% of all cells), and absence of expression. Tumor stage was based on clinical and morphological criteria. WHO classification (Lyon 2004) was used for determination of the histological grade.

RESULTS

Non-parametric Spearman's correlation showed that there was no statistically significant correlation between tumor stage and expression of cyclin E (ρ = -0331, p> 0.05). Also, no statistically significant correlation between grade and the expression of cyclin E (ρ = -0077, p> 0.05) was found. x2 test results showed no statistically significant difference (x2 = 2.136, p = 0.775) in the expression of cyclin E between upper and lower urothelium.

CONCLUSION

This study showed non significant decreased expression of cyclin E with poor differentiation, muscle invasion and upper/lower urothelium. Expression of cyclin E decreased with increasing histological grade and stage of the tumor.

Immunohistochemical analysis of gamma catenin in Wilms' tumors

The aim of our study was to investigate the expression of gamma-catenin in normal kidney and in Wilms' tumor by immunohistochemistry and to correlate the results with tumor stage, histological type, and prognostic group. We investigated 28 cases of Wilms' tumor, 2 Wilms' tumor metastases in lungs, and 1 specimen of normal renal tissue. Expression of gamma-catenin was detected in 14 cases. There was a weak inverse relationship between gamma-catenin expression and tumor stage. Expression of gamma-catenin was detected in various histologic types of Wilms' tumor, but there was no statistically significant correlation, except in cases with diffuse anaplasia that were negative. In 2 metastatic cases and in the case of bilateral Wilms' tumor gamma-catenin immunostaining was not observed Our findings suggest an absence of strong correlation between the loss of gamma-catenin and unfavorable outcome.

Significance of proto-oncogene Bcl-X(S/L) expression in Wilms tumor

The rate of apoptosis varies in malignant tumors, and it can be involved in diminishing tumor size. Different protein-regulators of apoptosis, such as Bcl-2, BclX, and Bax have an influence on the rate of apoptosis in various tumors. In human renal diseases, such as the experimental model of acute renal failure, and many tumors, including Wilms' tumor, the expression of antiapoptotic members of Bcl-2 family is increased, while the expression of proapoptotic members is low.

AIM

The aim of our study was to investigate Bcl-X(S/L) protein expression in Wilms' tumor, to compare it with the expression in normal renal tissue, as well as to see if there is a correlation between Bcl-X(S/L) expression in Wilms' tumor with tumor stage, histological type, prognostic group, or response to preoperative chemotherapy.

MATERIALS AND METHODS

Twenty-eight cases of Wilms' tumor (two cases with metastasis) and two samples of normal kidney tissue were studied using streptavidin-biotin-complex technique. Bcl-X(S/L) expression levels were semiquantitatively scored.

RESULTS

The expression of Bcl-X(S/L) was observed in the majority of cases (60.7%), more often in the blastemal than in the epithelial component of Wilms' tumor: 60.7% and 28.6%, respectively (p=0.02). There was a statistically significant inverse relationship between Bcl-X(S/L) expression and tumor stage (p=0.015). Bcl-X(S/L) was found less frequently in high-risk tumors then in tumors with good prognosis (p=0.02). Treated Wilms' tumors showed Bcl-X(S/L) expression more often than nontreated tumors, but the relationship was not statistically significant (p=0.08). Expression of Bcl-X(S/L) was detected in various histological types of Wilms' tumor, but there was no statistically significant association (p=0.82) except in cases with diffuse anaplasia (p=0.012), which were always negative. No Bcl-X(S/L) immunostaining was observed in two cases of metastasis or in one case of bilateral Wilms' tumor.

CONCLUSION

Our results suggest that the expression of Bcl-X(S/L) protein is associated with prognostic group, tumor stage, and presence of anaplasia.