Juchao Ren

Association between HIF1A P582S and A588T Polymorphisms and the Risk of Urinary Cancers: A Meta-Analysis

Purpose The hypoxia-inducible factor-1 alpha (HIF1A) plays a vital role in cancer initiation and progression. Previous studies have reported the existence of HIF1A P582S and A588T missense polymorphisms in renal, urothelial and prostatic carcinomas, however the effects remain conflicting. Therefore, we performed a meta-analysis to assess the association between these sites and the susceptibility of urinary cancers. Methods We searched the PubMed database without limits on language until Nov 25, 2012 for studies exploring the relationship of HIF1A P582S and A588T polymorphisms and urinary cancers. Still, article search was supplemented by screening the references of retrieved studies manually. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated to evaluate the strength of the associations between the two by RevMan 5.0 software. Simultaneously, publication bias was estimated by funnel plot and Begg’s test with Stata 12.1 software. Results Overall, 11 individual case-control studies with 5195 cases and 5786 controls for P582S polymorphism, and 9 studies with 3482 cases and 4304 controls for A588T polymorphism were respectively included in the final meta-analysis. For HIF1A P582S polymorphism, individuals with TT genotype showed 1.60 fold higher risk than the others carrying CT or CC genotypes in Caucasian population (OR = 1.60, 95% CI = 1.09–2.33, P heterogeneity = 0.11, P = 0.02). For HIF1A A588T polymorphism, the A allele was significantly correlated with higher urinary cancers risk in Asian population (OR = 1.41, 95% CI = 1.03–1.93, P heterogeneity = 0.22, P = 0.03). Still, significant associations were found for prostate cancer in the allele and dominant models (OR = 1.46, 95% CI = 1.01–2.12, P heterogeneity = 0.49, P = 0.04 and OR = 1.45, 95% CI = 1.00–2.12, P heterogeneity = 0.50, P = 0.05). Conclusions The current findings suggest that HIF1A P582S polymorphism correlates with urinary cancers risk in Caucasian population, while A588T polymorphism may increase the risk of urinary cancers in Asian population and prostate cancer.

Overexpression of Reptin in renal cell carcinoma contributes to tumor malignancies and its inhibition triggers senescence of cancer cells

OBJECTIVES Reptin is an AAA+ ATPase associated with several complexes involved in chromatin remodeling, transcriptional regulation, DNA damage repair, and telomerase activity. Functional studies have implicated reptin in many cellular processes highly relevant to cancer. In this study, we investigated reptin expression in renal cell carcinoma (RCC) and its biologic functions in RCC cells. MATERIALS AND METHODS A total of 81 RCC patients were involved in the study. Cancerous and adjacent normal renal tissues were analyzed for reptin expression using immunohistochemistry. Univariate association with survival was evaluated using Kaplan-Meier curves. Gene expression was depleted with specific small interference RNA. Clonogenesis, cellular senescence, and cell cycle distribution were examined by foci formation, β-galactosidase staining, and flow cytometry, respectively. Cell migration and invasion capability were determined by scratch migration assay and Matrigel invasion assay. RESULTS Reptin is overexpressed in cancerous tissues compared with tumor adjacent renal tissues. Cytoplasmic expression of reptin positively correlates with the poor differentiation of RCC, and predicts an unfavorable outcome for patients. Depleting reptin expression substantially inhibited clonogenic potential of cancer cells and induced senescence of RCC cells. Moreover, reptin depletion attenuated migration and invasion ability of RCC cells in vitro. CONCLUSIONS Reptin is overexpressed and aberrantly distributed in RCC. It is required for sustained proliferation of cancer cells by preventing cell growth arrest and senescence. Furthermore, reptin promotes cell migration and invasion, which may contribute to the progression of RCC. Therefore, reptin may prove to be a valuable target for prevention and treatment of renal cell carcinoma.

Microvessel density and heparanase over-expression in clear cell renal cell cancer: correlations and prognostic significances

BackgroundTumor angiogenesis is important in the progression of malignancies, and heparanase plays an important role in sustaining the pathology of clear cell renal cell cancer (ccRCC). The study was carried out to investigate the correlations between microvessel density (MVD) and heparanase expression containing prognostic significances in the patients with ccRCC.MethodsSpecimens from 128 patients with ccRCC were investigated by immunohistochemistry for MVD. RT-PCR and immunohistochemistry were used to detect heparanase expression. Correlations between MVD, heparanase expression, and various clinico-pathological factors were studied. The prognostic significances of MVD and heparanase expression were also analysed.ResultsWe discovered a statistically significant prevalence of higher MVD in ccRCC compared with adjacent normal renal tissues. MVD was positively correlated with TNM stage and distant metastasis in ccRCC patients, and was also correlated with the expression level of heparanase.Heparanase is over-expressed and correlated with TNM stage, histologic grade, distant metastasis and lymphatic metastasis in ccRCC. High MVD and heparanase over-expression inversely correlate with the survival of ccRCC patients.ConclusionsHeparanase contributes to angiogenesis of ccRCC and over-expression of heparanase is an independent predictors of prognosis for ccRCC. MVD is correlated with tumor development and metastasis in ccRCC.

Cytoplasmic Expression of Pontin in Renal Cell Carcinoma Correlates with Tumor Invasion, Metastasis and Patients’ Survival

Renal cell carcinoma (RCC) is the most lethal of all genitourinary malignancies. Distant metastasis represents the major cause of death in patients with RCC. Recent studies have implicated the AAA+ ATPase pontin in many cellular activities that are highly relevant to carcinogenesis. In this study, we demonstrate for the first time that pontin was up-regulated in RCC, and plays a previously unknown pro-invasive role in the metastatic progression of RCC through epithelial-to-mesenchymal transition (EMT) pathway. 28 pairs of freshly frozen clear cell RCC samples and the matched normal renal tissues analyzed by quantitative RT-PCR and western blotting demonstrated that pontin was up-regulated in clear cell RCC tissues than in normal renal tissues. In addition, immunohistochemistry was used to evaluate subcellular pontin expression in 95 RCC patients, and found that overexpression of pontin in cytoplasm positively correlated with the metastatic features, predicting unfavorable outcomes of RCC patients. Furthermore, in vitro experiments show pontin was predominantly expressed in cytoplasm of RCC cell lines, and a significant suppression of cell migration and invasion in pontin siRNA treated RCC cell lines was observed. Mechanistic studies show that pontin depletion up-regulated the E-cadherin protein and down-regulated vimentin protein, and decreased nuclear β-catenin expression, suggesting the involvement of EMT in pontin induced metastatic progression. Together, our data suggest pontin as a potential prognostic biomarker in RCC, and provide new promising therapeutic targets for clinical intervention of kidney cancers.

Lack of Association between hOGG1 Ser326Cys Polymorphism and the Risk of Bladder Cancer: A Meta-Analysis

Objective: In some but not all studies, hOGG1 Ser326Cys polymorphism has been reported to contribute to the risk of bladder cancer. To determine whether there is a significant association of hOGG1 Ser326Cys polymorphism with the susceptibility for bladder cancer, we performed a comprehensive meta-analysis. Methods: The electronic PubMed, Medline and Springer databases were searched for publications on the association between hOGG1 Ser326Cys polymorphism and bladder cancer through to May 20, 2011. Seven case-control studies were identified, including 2,474 cases and 2,408 controls. From these identified publications, crude odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the strength of association using fixed- or random-effects models. Two investigators each extracted data and conducted the analysis independently. Results: Overall, no significant associations were found between hOGG1 Ser326Cys polymorphism and bladder cancer in codominant models (GG vs. CC: OR 1.11, 95% CI 0.74–1.66, p = 0.63; GC vs. CC: OR 1.07, 95% CI 0.80–1.41, p = 0.65). Similarly, no significant associations with bladder cancer were observed in the recessive model (GG vs. GC+CC: OR 1.05, 95% CI 0.65–1.70, p = 0.85), dominant model (GG+GC vs. CC: OR 1.07, 95% CI 0.87–1.32, p = 0.53) and allele model (G vs. C: OR 1.06, 95% CI 0.90–1.26, p = 0.49). In the stratified analyses by ethnicity, control sources, pathology, Hardy-Weinberg equilibrium, significant associations were still not observed. Conclusions: The overall current literature on hOGG1 Ser326Cys polymorphism and the risk of bladder cancer suggests no statistically significant association between the two. Additional primary studies may be necessary to provide evidence of any significant association between this specific polymorphism and bladder cancer.

The clinical and biological significance of MICA in clear cell renal cell carcinoma patients

Major histocompatibility complex class I-related chains A (MICA), a ligand of Natural killer group 2, member D (NKG2D) receptor, is broadly upregulated in epithelial originated tumor cells. MICA plays a critical role in the immune surveillance against tumor cells and is associated with the prognosis of several malignancies. The aim of this study is to evaluate the clinical and biological significance of MICA in clear cell renal cell carcinoma (ccRCC). The expression of MICA was analyzed by quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC). Both MICA mRNA and protein levels were upregulated in ccRCC tissues, compared with normal tissues. IHC staining revealed a homogenous pattern of MICA staining within each tumor, which combined both membrane staining and granular cytoplasmic staining. Furthermore, high MICA expression was associated with lymph node metastasis and advanced clinical stage and predicted poor prognosis in patients with ccRCC. Gene set enrichment analysis (GSEA) was performed using RNA-sequencing data from The Cancer Genome Atlas Research Network (TCGA) to elucidate the biological role of MICA in ccRCC and revealed that MICA was significantly associated with the epithelial-to-mesenchymal transition (EMT) gene set, which was further confirmed by qRT-PCR. Our findings contribute to the studies on biomarkers of kidney cancers and the mechanism of renal cancer progression driven by EMT pathway.

Eukaryotic Translation Initiation Factor 3b is both a Promising Prognostic Biomarker and a Potential Therapeutic Target for Patients with Clear Cell Renal Cell Carcinoma

Eukaryotic translation initiation factors (eIFs) constitute a new class of therapeutic cancer targets. EIF3b is the major scaffold protein of eIF3 (the largest core of eIFs). We sought to define the role played by and the mechanism of action of eIF3b in patients with clear cell renal cell carcinoma (ccRCC). We found that high-level eIF3b expression in tumors was not only associated with an aggressive tumor phenotype, but was also independently prognostic for patients with ccRCC. Knockdown of eIF3b impaired the action of the Akt pathway, thus inhibiting cell proliferation by disrupting the cell cycle and triggering apoptosis. Furthermore, the epithelial-to-mesenchymal transition was impaired after eIF3b depletion, via suppression of cell migration and invasion. Additionally, eIF3b knockdown significantly inhibited the growth of subcutaneous xenografts in mice. Together, these data show that eIF3b is both a promising prognostic biomarker and a potential therapeutic target for patients with ccRCC.

CIP2A Promotes Proliferation, Invasion and Chemoresistance to Cisplatin in Renal Cell Carcinoma

CIP2A is a well-known oncoprotein whose expression is elevated in multiple human solid tumor types. However, its role in renal cell carcinoma (RCC) development is poorly understood. Thus, in our present study, we used the renal cancer cell lines 786-O, A498 and CAKI-1 and the renal epithelial cell line HK-2 to clarify the function of CIP2A in RCC. We found that CIP2A expression is much higher in the RCC cells than in the normal renal epithelial cell. Lentivirus covered coding region CIP2A cDNA sequence and CIP2A siRNA were used to up and down regulate CIP2A expression in vitro. We found that overexpression of CIP2A promoted G1/S transition and cell proliferation. In addition, up-regulation of CIP2A significantly enhanced the invasion and migration capabilities of the cells. Furthermore, CIP2A promoted epithelial-mesenchymal transformation (EMT) and chemoresistance to cisplatin in RCC cells. Taken together, our findings demonstrate that CIP2A plays an important role in proliferation, invasion and chemoresistance to cisplatin in RCC cells. CIP2A may serve as an ideal molecular target for RCC therapeutics.

Pretreatment Serum Cystatin C Levels Predict Renal Function, but Not Tumor Characteristics, in Patients with Prostate Neoplasia

To evaluate the role of Cystatin C (Cys-C) in tumorigenesis and progression of prostate cancer (PCa), we retrospectively collected the clinical information from the records of 492 benign prostatic hyperplasia (BPH), 48 prostatic intraepithelial neoplasia (PIN), and 173 PCa patients, whose disease was newly diagnosed and histologically confirmed. Pretreatment serum Cys-C levels were compared across the various groups and then analyzed to identify relationships, if any, with clinical and pathological characteristics of the PCa patient group. There were no significant differences in serum Cys-C levels among the three groups (P > 0.05). In PCa patients with normal SCr levels, patient age was correlated with serum Cys-C level (P ≤ 0.001) but did not correlate with alkaline phosphatase (AKP), lactate dehydrogenase (LDH), prostate specific antigen (PSA), Gleason score, or bone metastasis status (P > 0.05). Age and SCr contributed in part to the variations in serum Cys-C levels of PCa patients (r = 0.356, P ≤ 0.001; r = 0.520, P ≤ 0.001). In conclusion, serum Cys-C levels predict renal function in patients with prostate neoplasia, but were not a biomarker for the development of prostate neoplasia, and were not correlated with the clinicopathological characteristics of PCa.