Huimin An

Klotho suppresses tumor progression via inhibiting PI3K/Akt/GSK3β/Snail signaling in renal cell carcinoma

Klotho is an anti‐aging protein predominantly expressed in renal tubular epithelial cells. Although Klotho was recently identified as a tumor suppressor gene in a variety of cancers, the potential role and molecular events for Klotho in renal cell carcinoma (RCC) remain obscure. In the present study, immunohistochemical staining in tissue microarrays containing 125 RCC samples showed that intratumoral Klotho levels were negatively correlated with tumor size, TNM stage and nuclear grade. The overall survival rate of RCC patients with high Klotho expression was significantly higher than that of patients with low Klotho expression. Functional analysis after gain and loss of Klotho expression revealed that Klotho blunted epithelial‐mesenchymal transition and cellular migration and invasion in RCC. Also, no alteration of α‐2,6‐sialidase activity was found after Klotho overexpression in RCC. The molecular signals for this phenomenon involved the Klotho‐mediated inhibition of PI3K/Akt/GSK3β/Snail pathway. Importantly, compared to localized RCC tissues, advanced RCC tissues exhibited low Klotho expression accompanied with high pAkt and Snail expression. These results indicate Klotho acts as a tumor suppressor by inhibiting PI3K/Akt/GSK3β/Snail signaling, thus suppressing epithelial‐mesenchymal transition and tumor migration and invasion during RCC progression. As a result, Klotho might be used as a potential therapy for advanced RCC.

Systemic inflammation score predicts postoperative prognosis of patients with clear-cell renal cell carcinoma

Background:Growing evidence indicates that inflammation has a crucial role in the development and progression of cancer. We developed a novel systemic inflammation score (SIS) based on preoperative serum albumin and lymphocyte-to-monocyte ratio (LMR), and examined its prognostic value for patients with clear-cell renal cell carcinoma (ccRCC) after surgery.Methods:The study comprised 441 ccRCC patients undergoing nephrectomy between 2008 and 2009 in a single centre. The SIS was developed and its associations with clinicopathological features and overall survival (OS) were evaluated.Results:The SIS consisted of serum albumin and LMR that were both retained as independent indicators adjusting for other haematological and laboratory markers of systemic inflammation responses and traditional clinicopathological features. A high SIS was significantly associated with aggressive tumour behaviours and served as an independent prognostic factor of reduced OS. Furthermore, the SIS could significantly stratify patient prognosis in different tumour stages and Mayo Clinic stage, size, grade and necrosis scores. Incorporation of the SIS into a prognostic model including TNM stage, Fuhrman grade and lymphovascular invasion generated a nomogram, which predicted accurately 3- and 5-year survival for ccRCC patients.Conclusions:The SIS as a potentially powerful prognostic biomarker might improve traditional clinicopathological analysis to refine clinical outcome prediction for ccRCC patients after surgery.

Sunitinib induces cellular senescence via p53/Dec1 activation in renal cell carcinoma cells

Although multitargeted tyrosine kinase inhibitor sunitinib has been used as first‐line therapeutic agent against metastatic renal cell carcinoma (mRCC), the molecular mechanism and functional role per se for its therapeutic performance remains obscure. Our present study revealed that sunitinib‐treated RCC cells exhibit senescence characteristics including increased SA‐β‐gal activity, DcR2 and Dec1 expression, and senescence‐associated secretary phenotype (SASP) such as proinflammatory cytokines interleukin (IL)‐1α, IL‐6 and IL‐8 secretion. Moreover, sunitinib administration also led to cell growth inhibition, G1‐S cell cycle arrest and DNA damage response in RCC cells, suggesting therapeutic significance of sunitinib‐induced RCC cellular senescence. Mechanistic investigations indicated that therapy‐induced senescence (TIS) following sunitinib treatment mainly attributed to p53/Dec1 signaling activation mediated by Raf‐1/NF‐κB inhibition in vitro. Importantly, in vivo study showed tumor growth inhibition and prolonged overall survival were associated with increased p53 and Dec1 expression, decreased Raf‐1 and Ki67 staining, and upregulated SA‐β‐gal activity after sunitinib treatment. Immunohistochemistry analysis of tumor tissues from RCC patients receiving sunitinib neoadjuvant therapy confirmed the similar treating phenotype. Taken together, our findings suggested that sunitinib treatment performance could be attributable to TIS, depending on p53/Dec1 activation via inhibited Raf‐1/nuclear factor (NF)‐κB activity. These data indicated potential insights into therapeutic improvement with reinforcing TIS‐related performance or overcoming SASP‐induced resistance.

Clinical significance of tumor-derived IL-1β and IL-18 in localized renal cell carcinoma: Associations with recurrence and survival

PURPOSE Interleukin-1β (IL-1β) and IL-18 are products of activated inflammasomes that play central roles in innate immunity and inflammation. This study was aimed to determine the effect of tumor-derived IL-1β and IL-18 on recurrence and survival of patients with localized clear cell renal cell carcinoma (ccRCC) following surgery. METHODS We retrospectively enrolled 267 patients with localized ccRCC undergoing nephrectomy at a single center. Clinicopathologic features, recurrence-free survival (RFS), and overall survival (OS) were recorded. IL-1β and IL-18 levels were assessed by immunohistochemistry in tumor tissues. The Kaplan-Meier method was used to compare survival curves. Cox regression models were used to analyze the effect of prognostic factors on RFS and OS. Concordance index was calculated to assess predictive accuracy. RESULTS Both high IL-1β and high IL-18 levels were associated with increased risk of recurrence (P<0.001 and P<0.001, respectively) and reduced survival (P<0.001 and P = 0.001, respectively). The combination of IL-1β and IL-18 expression (IL-1β/IL-18 signature) could further refine prognostic stratification. Multivariate analyses confirmed that IL-1β/IL-18 signature was an independent prognostic factor for RFS and OS (P = 0.005 and P = 0.044, respectively). The predictive accuracy of well-established prognostic models improved when the IL-1β/IL-18 signature was added. Notably, the improvement in prediction was mainly observed in patients with low-risk disease. CONCLUSIONS The combined high expression of IL-1β and IL-18 is an independent predictor for poor prognosis in patients with localized ccRCC, and the prognostic value is more pronounced in patients with low-risk disease.

High expression of Solute Carrier Family 1, member 5 (SLC1A5) is associated with poor prognosis in clear-cell renal cell carcinoma

Solute Carrier Family 1, member 5 (SLC1A5), also named as ASCT2, a major glutamine transporter, is highly expressed in various malignancies and plays a critical role in the transformation, growth and survival of cancer cells. The aim of this study was to assess the clinical significance of SLC1A5 in patients with clear-cell renal cell carcinoma (ccRCC). SLC1A5 expression was evaluated by immunohistochemistry on tissue microarrays. Kaplan-Meier method was conducted to compare survival curves. Univariate and multivariate Cox regression models were applied to assess the impact of prognostic factors on overall survival (OS). A nomogram was then constructed on the basis of the independent prognosticators identified on multivariate analysis. The predictive ability of the models was compared using Receiver operating characteristic (ROC) analysis. Our data indicated that high expression of SLC1A5 was significantly associated with advanced TNM stage, higher Fuhrman grade and shorter OS in ccRCC patients. Multivariate analysis confirmed that SLC1A5 was an independent prognosticator for OS. A nomogram integrating SLC1A5 and other independent prognosticators was constructed, which showed a better prognostic value for OS than TNM staging system. In conclusion, high SLC1A5 expression is an independent predictor of adverse clinical outcome in ccRCC patients after surgery.

P2X7 receptor predicts postoperative cancer‐specific survival of patients with clear‐cell renal cell carcinoma

The P2X7 receptor, an ATP‐gated plasma membrane ion channel, is involved in inflammation, apoptosis and cell proliferation, and thereby plays a crucial role during oncogenic transformation in various malignancies. This study aims to evaluate the impact of P2X7 receptor expression on postoperative cancer‐specific survival of patients with clear‐cell renal cell carcinoma (ccRCC). A total of 273 patients with ccRCC undergoing nephrectomy at a single institution were retrospectively enrolled in this study, among which 86 patients died of this disease and six patients died of other causes. Clinicopathologic features and cancer‐specific survival (CSS) were recorded. P2X7 expression was assessed by immunohistochemistry in clinical specimens. Kaplan–Meier method with log rank test was performed to compare survival curves. Cox regression models were used to evaluate the prognostic values of variables on CSS. Concordance index was calculated to assess prognostic accuracy of prognostic models. Median follow‐up period was 90 months (range, 11–120 months). Intratumoral P2X7 expression was significantly lower than peritumoral tissues (P < 0.001). Moreover, high intratumoral P2X7 expression, which was significantly associated with shorten CSS (P < 0.001), high TNM stage (P = 0.038), Fuhrman grade (P = 0.035), SSIGN (stage, size, grade, and necrosis) score (P = 0.021) and University of California Integrated Staging System (UISS) score (P = 0.007), was indicated to be an independent prognostic factor for CSS (hazard ratio [HR], 1.693; P = 0.034). The prognostic accuracy of TNM stage, UISS and SSIGN scoring models was improved when intratumoral P2X7 expression was added. Intratumoral P2X7 expression is a potential independent adverse prognostic indicator for postoperative CSS of patients with ccRCC.

Decreased Expression of SETD2 Predicts Unfavorable Prognosis in Patients With Nonmetastatic Clear-Cell Renal Cell Carcinoma

AbstractDNA sequencing revealed that mutations in SETD2 occur in 3% to 12% of clear-cell renal cell carcinoma (ccRCC) cases and are associated with poor clinical outcome. In this study, we used an immunohistochemistry (IHC) assay to evaluate the impact of SETD2 loss, with expression of H3K36me3, a nonredundantly histone modification by SETD2, on recurrence and survival of nonmetastatic ccRCC patients after nephrectomy.SETD2 and H3K36me3 were assessed in 192 nonmetastatic ccRCC patients enrolled retrospectively from a single institution. Kaplan–Meier and Cox regression analysis were used to associate prespecified SETD2/H3K36me3 score with overall survival (OS) and recurrence-free survival (RFS). And a nomogram was constructed to predict OS at 10 years.Patients with low expression of SETD2 were prone to possess large tumor size and advanced pT stage. And low H3K36me3 expression was associated with larger tumor size. A prespecified combined score based on SETD2 and H3K36me3 expression remained an independent prognosticator for OS and RFS, which was associated with tumor size, pT stage, and sarcomatoid. Furthermore, using prespecified SETD2/H3K36me3 score could stratify nonmetastatic ccRCC patients into different risk subgroups, especially in patients dichotomized by pT stage and Fuhrman grade, respectively. Finally, the C-index for predicting OS increased from 0.727 to 0.747, after adding SETD2/H3K36me3 score to pT stage and Fuhrman grade.The combined score based on expression of SETD2 and H3K36me3 using IHC could predict poor clinical outcomes in nonmetastatic ccRCC patients, and it may benefit preoperative risk stratification and guide treatment planning in the future.

High APOBEC3B expression is a predictor of recurrence in patients with low-risk clear cell renal cell carcinoma

PURPOSE APOBEC3B is a member of the cytosine deaminase family, which converts cytosine to uracil during RNA editing and retrovirus or retrotransposon restriction. Recent evidence has revealed that APOBEC3B-catalyzed genomic DNA deamination could provide genetic fuel for cancer development, metastasis, and even treatment resistance. The aim of this study was to assess the association between APOBEC3B expression and the risk of recurrence after surgery in patients with renal cell carcinoma (RCC). METHODS We retrospectively enrolled 299 consecutive patients with RCC who underwent nephrectomy at a single center in 2008. Clinicopathologic variables and recurrence-free survival (RFS) were recorded. APOBEC3B expression levels were determined by immunohistochemistry in tumor tissues. Kaplan-Meier method was applied to compare survival curves. Cox regression models were fitted to analyze the effect of prognostic factors on RFS. The Harrell concordance index was calculated to assess predictive accuracy. RESULTS High APOBEC3B expression was associated with an increased risk of recurrence in patients with clear cell RCC (ccRCC) (P<0.001) rather than in patients with non-ccRCC (P = 0.247). After backward elimination, APOBEC3B expression was identified as an independent prognostic factor for RFS in patients with clear cell histology (P = 0.016). The predictive accuracy of the Leibovich prognostic score was improved when APOBEC3B expression was incorporated. Notably, the improvement in prediction mainly took place in patients with low-risk disease defined by the Leibovich score. CONCLUSIONS High APOBEC3B expression is an independent predictor of recurrence in patients with ccRCC, and the prognostic value is most prominent in those with low-risk disease.

CXC chemokine receptor 2 is associated with postoperative recurrence and survival of patients with non-metastatic clear-cell renal cell carcinoma

BACKGROUND Aberrant CXC chemokine receptor 2 (CXCR2) expression has been shown to promote angiogenesis and proliferation in renal cell carcinoma (RCC). Our current study aims to evaluate the prognostic significance of CXCR2 in patients with non-metastatic clear-cell renal cell carcinoma (ccRCC). METHODS We retrospectively enrolled 375 patients with non-metastatic ccRCC undergoing nephrectomy at Zhongshan Hospital, Fudan University between 2003 and 2008. The cohort was split into a training set (n=184) and a validation set (n=191). CXCR2 expression was assessed by immunohistochemical staining and its association with clinicopathologic features and prognosis were evaluated. RESULTS CXCR2 expression was significantly associated with tumour size (P=0.036 and P=0.016, respectively) and Fuhrman grade (P=0.009 and P=0.001, respectively) in the training and validation sets. Moreover, high CXCR2 expression indicated poor overall survival (OS) (P<0.001 and P=0.001, respectively) and recurrence-free survival (P<0.001 and P<0.001, respectively) in the training and validation sets. The incorporation of CXCR2 into the T stage and Fuhrman grade would help to refine individual risk stratification. Furthermore, CXCR2 expression was identified as an independent adverse prognostic factor for survival (P<0.001) and recurrence (P<0.001). A predictive nomogram was generated with identified independent prognosticators to assess patient recurrence-free survival at 5 and 10 years. CONCLUSIONS CXCR2 is a potential independent adverse prognostic biomarker for recurrence and survival of patients with non-metastatic ccRCC after nephrectomy.

Prognostic value of interleukin-6 and interleukin-6 receptor in organ-confined clear-cell renal cell carcinoma: a 5-year conditional cancer-specific survival analysis.

Background:Interleukin-6 (IL-6) is the major cytokine that induces transcriptional acute and chronic inflammation responses, and was recently incorporated as a recurrence prognostication signature for localised clear-cell renal cell carcinoma (ccRCC). As the prognostic efficacy of initial risk factors may ebb during long-term practice, we aim to report conditional cancer-specific survival (CCSS) of RCC patients and evaluate the impact of IL-6 as well as its receptor (IL-6R) to offer more relevant prognostic information accounting for elapsing time.Methods:We enrolled 180 histologically proven localised ccRCC patients who underwent nephrectomy between 2001 and 2004 with available pathologic information. Five-year CCSS was determined and stratified by future prognostic factors. Constant Cox regression analysis and Harrell’s concordance index were used to indicate the predictive accuracy of established models.Results:The 5-year CCSS of organ-confined ccRCC patients with both IL-6- and IL-6R-positive expression was 52% at year 2 after surgery, which was close to locally advanced patients (48%, P=0.564) and was significantly poorer than organ-confined patients with IL-6- or IL-6R-negative expression (89%, P<0.001). Multivariate analyses proved IL-6 and IL-6R as independent predictors after adjusting for demographic factors. Concordance index of pT-IL-6-IL-6R risk stratification was markedly higher compared with the stage, size, grade and necrosis prognostic model (0.724 vs 0.669, P=0.002) or UCLA Integrated Staging System (0.724 vs 0.642, P=0.007) in organ-confined ccRCC population during the first 5 years.Conclusions:Combined IL-6 and IL-6R coexpression emerges as an independent early-stage immunologic prognostic factor for organ-confined ccRCC patients.