Analysis of various potential prognostic markers and survival data in clear cell renal cell carcinoma

Associations between tumor grade, contrast-enhanced ultrasound features, and microvascular density in patients with clear cell renal cell carcinoma: a retrospective study

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) comprises 70% of all renal cell carcinomas (RCCs). Currently, the most important prognostic factor for this type of carcinoma is the World Health Organization/International Society of Urological Pathology (WHO/ISUP) grade. However, nonsurgical methods are rarely used to determine a tumor's WHO/ISUP grade, thus limiting the development of nonsurgical therapies. Due to variations in microvascular density (MVD) at different stages of tumor growth, contrast-enhanced ultrasound (CEUS) features may provide a noninvasive method for evaluating the WHO/ISUP grade of ccRCC.

METHODS

In this study, we analyzed confirmed cases of ccRCC using CEUS features. We also used CD34 and CD31 antibodies to determine MVD. The heterogeneity of CD34 and CD31 expressions were used to determine different degrees of angiogenesis.

RESULTS

When compared to WHO/ISUP grade I/II (G1/G2) tumors, grade III/IV (G3/G4) tumors had reduced peak intensity (PI) (P=0.006), time to peak (TTP) (P<0.001), and relative enhancement percentage index (∆PI%) (P<0.001). However, the frequency of incomplete pseudocapsule (P=0.049) and slow wash-in (P=0.001) was significantly higher in G3/G4 tumors. A cut-off value of ∆PI% <33.15% (P<0.001) allowed identification of G3/G4 tumors with an area under the curve (AUC) of 0.80 [95% confidence interval (CI): 0.70 to 0.91) and a sensitivity of 80%. The mean CD34+ MVD (P<0.001) and CD31+ MVD (P<0.001) were significantly lower in G3/G4 tumors. A positive correlation was revealed between ∆PI% and MVD. There was a statistically significant difference in the density of undifferentiated vessels between the slow wash-in and fast wash-in cases (P<0.001).

CONCLUSIONS

The features of CEUS are effective for differentiating G3/G4 tumors from G1/G2. There was a positive correlation detected between ∆PI% and MVD, and the density of undifferentiated vessels showed a significant difference between slow wash-in and fast wash-in cases. These findings indicate that CEUS can enable the sonographic visualization of tumor angiogenesis and thus be considered an acceptable method for the nonsurgical assessment of tumor microvascular distribution and grade.

Research on the prognosis of different types of microvessels in bladder transitional cell carcinoma

BACKGROUND

At present, there is controversy on the role of microvessel density (MVD) in tumors as a prognostic indicator of bladder transitional cell carcinoma (BTCC). However, the MVD in tumors is simply classified based on the expression of several different vascular markers, which has not been related to analytical research on the prognosis of patients with BTCC.

AIM

To explore the classification of blood vessels in tumors and studied the relationship between MVD and the prognosis of patients with BTCC.

METHODS

The tissue mass was detected by tissue microarray and immunohistochemical analysis with monoclonal antibodies against CD31, CD34, CD105, and vascular smooth muscle actin to investigate the MVD in BTCC. The measurement data are expressed as the mean ± SD. The difference between the groups was analyzed by the t-test, the counting data were analyzed by χ² test. The Kaplan-Meier survival curve was estimated by the product-limit method. The log-rank time-series test was employed to compare the tumor-free survival curves.

RESULTS

The MVD was closely related to the pathological grade, invasive depth, and prognosis of BTCC. Significant differences were found between grade I and grade II, grade II and grade III, superficial and invasive type, and the tumor-free survival group and the recurrence or metastasis group (P < 0.01). Multivariate analysis showed that undifferentiated MVD was an independent prognostic factor for patient survival time. An inverse correlation between undifferentiated tumor MVD and differentiated tumor MVD in BTCC was also shown.

CONCLUSION

The classification of blood vessels in BTCC could act as an important prognostic indicator and may also be of great significance in the treatment of cancer.

miR-129-5p inhibits clear cell renal cell carcinoma cell proliferation, migration and invasion by targeting SPN

Objective

Our study aims to investigate the mechanism of the miR-129-5p/SPN axis in clear cell renal cell carcinoma (ccRCC), providing a novel direction for the targeted therapy of ccRCC.

Methods

Bioinformatics methods were implemented to find the differentially expressed genes (DEGs) associated with ccRCC from TCGA database. qRT-PCR was performed to detect miR-129-5p and SPN mRNA expression, while western bot was carried out for the detection of protein expression of SPN. Bioinformatics analysis was used to predict the binding sites of miR-129-5p on SPN 3’UTR, while dual-luciferase assay was conducted to verify their binding relationship. CCK-8 assay, colony formation assay, wound healing assay and Transwell assay were employed to measure ccRCC cell proliferative ability, cell formation ability, cell migratory and invasive abilities. Flow cytometry was implemented to assess cell cycle and apoptosis.

Results

miR-129-5p exhibited a significantly down-regulated expression level in ccRCC, while SPN showed a remarkably up-regulated expression level. Overexpressed miR-129-5p inhibited ccRCC cell proliferative, invasive and migratory capacities while induced cell cycle arrest in G0/G1 phase and promoted cell apoptosis. Dual-luciferase assay confirmed that there was a binding relationship between miR-129-5p and SPN. Moreover, overexpressed miR-129-5p remarkably reduced SPN expression in cancer cells, weakened the promoting effect of SPN on cell proliferation, migration, invasion and cell cycle progress, and led to enhanced cell apoptotic activity.

Conclusions

Our study proves the regulatory effect of the miR-129-5p/SPN axis in ccRCC, and provides a novel potential target for precise treatment of patients with ccRCC.

A Two-DNA Methylation Signature to Improve Prognosis Prediction of Clear Cell Renal Cell Carcinoma

PURPOSE

Effective biomarkers and models are needed to improve the prognostic prospects of clear cell renal cell carcinoma (ccRCC). The purpose of this work was to identify DNA methylation biomarkers and to evaluate the utility of DNA methylation analysis for ccRCC prognosis.

MATERIALS AND METHODS

An overview of genome-wide methylation of ccRCC tissues derived from The Cancer Genome Atlas (TCGA) database was download for analysis. DNA methylation signatures were identified using Cox regression methods. The potential clinical significance of methylation biomarkers acting as a novel prognostic markers was analyzed using the Kaplan-Meier method and receiver operating characteristic (ROC) curves.

RESULTS

This study analyzed data for 215 patients with information on 23171 DNA methylation sites and identified a two-DNA methylation signature (cg18034859, cg24199834) with the help of a step-wise multivariable Cox regression model. The area under the curve of ROCs for the two-DNA methylation signature was 0.819. The study samples were stratified into low- and high-risk classifications based on an optimal threshold, and the two groups showed markedly different survival rates. Moreover, the two-DNA methylation marker was suitable for patients of varying ages, sex, stages (I and IV), and histologic grade (G2).

CONCLUSION

The two-DNA methylation signature was deemed to be a potential novel prognostic biomarker of use in increasing the accuracy of predicting overall survival of ccRCC patients.

Prognostic significance of VHL, HIF1A, HIF2A, VEGFA and p53 expression in patients with clear‑cell renal cell carcinoma treated with sunitinib as first‑line treatment

Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cell cancer, characterized by the highest mortality rate among other RCC subtypes due to the occurrence of metastasis and drug resistance following surgery. The Von Hippel-Lindau tumor suppressor (VHL)-hypoxia-inducible factor 1 subunit α (HIF1A)/hypoxia-inducible factor 2α (HIF2A)-vascular endothelial growth factor A (VEGFA) protein axis is involved in the development and progression of ccRCC, whereas sunitinib, a tyrosine kinase inhibitor, blocks the binding of VEGFA to its receptor. The aim of the present study was to examine the possible association of the gene expression of VHL, HIF1A, HIF2A, VEGFA and tumor protein P53 (P53) in cancer tissue with the outcome of ccRCC patients who were treated with sunitinib as first-line therapy following nephrec-tomy. A total of 36 ccRCC patients were enrolled, 11 of whom were administered sunitinib post-operatively. Tumor and control samples were collected, and mRNA and protein levels were assessed by reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. High mRNA and protein expression levels of HIF2A and VEGFA were found to be associated with shorter overall survival (OS) and progression-free survival (PFS) rates, as well as with unfavorable risk factors of cancer recurrence and mortality. Resistance to sunitinib was also observed; the OS and PFS rates were shorter (median OS and PFS: 12 and 6 months, respectively, vs. undetermined). Sunitinib resistance was associated with high HIF2A and VEGFA protein levels (b=0.57 and b=0.69 for OS and PFS, respectively; P<0.001). Taken together, the findings of this study suggest that the protein levels of HIF2A and VEGFA in tumor tissue may serve as independent prognostic factors in ccRCC. ccRCC patients with increased intratumoral HIF2A and VEGFA protein levels, and unaltered VHL protein levels, are not likely to benefit from sunitinib treatment following nephrectomy; however, this hypothesis requires verification by large-scale replication studies.

[The morphological and molecular genetic characteristics of sarcomatoid chromophobe renal cell carcinoma]

The paper describes a case of chromophobe renal cell carcinoma growing into the muscular layer of the descending colon and with metastases in 4 lymph nodes of paranephral tissue in a 66-year-old woman. The tumor had a zonal structure with an alternation of epithelioid and sarcomatoid structural sites and with the signs of grades I, II and III according to the grading system by Paner and et al. (2010). The sarcomatoid renal component occupied about 70.0% of the tumor. There was a pronounced immunohistochemical reaction with VEGF-A (5 scores), a high Ki-67 proliferation index (70%), and a large number of tumor cells with nuclear p53 expression (85%) in the areas with minimal differentiation and sarcomatoid elements (Grade III). These signs can serve as criteria for the aggressive behavior of the tumor. A large volume of the sarcomatoid carcinoma component and a strong reaction with VEGF-A are indications for targeted therapy with anti-VEGF drugs.

Prognostic Role of Hypoxia-Inducible Factor-2α Tumor Cell Expression in Cancer Patients: A Meta-Analysis

Hypoxia-inducible factor-2α (HIF-2α) plays an important role in tumor progression and metastasis. A number of studies have evaluated the correlation between HIF-2α overexpression and clinical outcome in cancer patients but yielded inconsistent results. To comprehensively and quantitatively summarize the evidence on the capability of HIF-2α to predict the prognosis of cancer patients with solid tumors, a meta-analysis was carried out. Renal cell carcinoma (CC-RCC) was separately analyzed due to an alternative mechanism of regulation. Systematic literature searches were performed in PubMed and Embase databases for relevant original articles until February 2018. Forty-nine studies with 6,052 patients were included in this study. The pooled hazard ratios (HRs) with corresponding confidence intervals were calculated to assess the prognostic value of HIF-2α protein expression in tumor cells. The meta-analysis revealed strong significant negative associations between HIF-2α expression and five endpoints: overall survival [HR = 1.69, 95% confidence interval (95% CI) 1.39-2.06], disease-free survival (HR = 1.87, 95% CI 1.2-2.92), disease-specific survival (HR = 1.57, 95% CI 1.06-2.34), metastasis-free survival (HR = 2.67, 95% CI 1.32-5.38), and progression-free survival (HR = 2.18, 95% CI 1.25-3.78). Subgroup analyses revealed similar associations in the majority of tumor sites. Overall, these data demonstrate a negative prognostic role of HIF-2α in patients suffering from different types of solid tumors.

The prognostic value of BAP1, PBRM1, pS6, PTEN, TGase2, PD-L1, CA9, PSMA, and Ki-67 tissue markers in localized renal cell carcinoma: A retrospective study of tissue microarrays using immunohistochemistry

OBJECTIVE

To assess the prognostic roles of BAP1, PBRM1, pS6, PTEN, TGase2, PD-L1, CA9, PSMA, and Ki-67 tissue biomarkers in localized renal cell carcinoma (RCC).

METHODS

Patients who underwent a nephrectomy during 1992-2015 and had a primary specimen of their kidney tumor were included. The nine tissue biomarkers were immunohistochemically stained on tissue microarrays of RCC, and the semi-quantitative H-score, including intensity score, was used to grade the sample. The Cox proportional hazards model was used to evaluate tissue markers significant for overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) after adjusting for significant clinicopathological parameters.

RESULTS

Samples from 351 RCC patients were included. The mean age of the patients was 53.9 years; the rates of pathologic T1-2/≥T3 stage, Fuhrman 1+2/3+4 grade, recurrence, and death were 269/65(80.5/19.5%), 222/107 (67.5/32.5%), 6.6%, and 10.5%, respectively. Median OS, CSS, and RFS were 220.6, 220.6, and 147.1 months, respectively. The multivariable analysis showed that pathologic T stage and Fuhrman nuclear grade were significantly associated with OS and CSS. Pathologic T stage and tumor size were associated with RFS. After adjusting for these significant prognostic clinicopathological factors, Ki-67 was significantly associated with OS (hazard ratio [HR], 2.7), CSS (HR, 3.82), and RFS (HR, 4.85) and pS6 was associated with CSS (HR, 8.63) and RFS (HR, 8.51) in the multivariable model (p<0.05).

CONCLUSION

pS6 and Ki-67 are significant prognostic factors of RCC; however, BAP1, PBRM1, TGase 2, PD-L1, CA9, PTEN loss, and PSMA markers did not show this association.