Advanced renal cell carcinoma: current and emerging management strategies

RBM47 restrains renal cell carcinoma progression and chemoresistance through interacting with lncRNA HOXB-AS1

RNA binding proteins have the critical role in renal cell carcinoma (RCC) progression. However, the role of RBM47 in RCC has not been elucidated. In this study, we found that RBM47 was downregulated in RCC tissues and its expression was negatively correlated with the prognosis of RCC patients. Also, we found that the expression of RBM47 was regulated by CBP/P300-mediated H3K27ac in RCC. Functionally, RBM47 restrained RCC cells proliferation and metastasis. Mechanistically, RBM47 interfered with the interaction between HOXB-AS1 and p53 proteins via directly binding with HOXB-AS1, finally promoted the entry of p53 into the nucleus and therefore activated the p53 signaling. Moreover, RBM47 had a synergistic anticancer effect with sunitinib both in vivo and in vitro.

Comprehensive analysis of LAMC1 expression and prognostic value in kidney renal papillary cell carcinoma and clear cell carcinoma

Background: Laminin subunit gamma 1 (LAMC1) protein is associated with tumor cell invasion and metastasis. However, its role in kidney cancer remains unclear. In this work, we sought to probe the expression as well as its carcinogenic mechanisms of LAMC1 in kidney renal papillary cell carcinoma (KIRP) and kidney renal clear cell carcinoma (KIRC).

Methods: Public databases including TIMER, Oncomine, UALCAN, TISIDB, TCGA, Kaplan–Meier plotter, UCSC Xena, cBioPortal, SurvivalMeth, KEGG, GeneMANIA, Metascape, GSCALite and GDSC were adopted, and the expression, clinical pathological correlation, prognostic signatures, dominant factors influencing LAMC1 expression, DNA methylation levels, gene mutations, copy number variations, functional networks, and drug sensitivity were analyzed. Expression of LAMC1 protein in clinical KIRP and KIRC was validated using tissue array.

Results:LAMC1 expression in KIRP and KIRC were significantly higher than those in normal tissues. High LAMC1 expression indicated poor overall survival in KIRP patients and better overall survival in KIRC patients. Through the univariate and multivariate Cox analysis, we found that high LAMC1 expression was a potential independent marker for poor prognosis in KIRP, however it implied a better prognosis in KIRC by univariate Cox analysis. In addition, the LAMC1 expression in KIRP and KIRC was negatively correlated with methylation levels of LAMC1 DNA. Interestingly, LAMC1 expression was positively correlated with the infiltration of CD8⁺ T cells, dendritic cells and neutrophils in KIRP; however, it was positively correlated with the infiltration of CD4⁺ T cells, macrophages and neutrophils but negatively correlated with B cells in KIRC. Moreover, high level of CD8⁺ T cells is beneficial for KIRC prognosis but opposite for KIRP. LAMC1 may participate in signaling pathways involved in formation of adherens junction and basement membrane in KIRP and KIRC, and the high expression of LAMC1 is resistant to most drugs or small molecules of the Genomics of Drug Sensitivity in Cancer database.

Conclusion: Enhanced LAMC1 expression suggests a poor prognosis in KIRP while a better prognosis in KIRC, and these opposite prognostic signatures of LAMC1 may be related to different immune microenvironments.

CircME1 promotes aerobic glycolysis and sunitinib resistance of clear cell renal cell carcinoma through cis-regulation of ME1

Circular RNAs (circRNAs) play critical roles in clear cell renal cell carcinoma (ccRCC). However, their involvement in sunitinib resistance remains largely unknown. Herein, we identified a novel circRNA, named circME1, which contributes to sunitinib resistance development in ccRCC. CircME1 also promoted proliferation, migration, and invasion of ccRCC cells. Further mechanism analysis showed that circME1 interacted with U1 snRNP at the promoter of its parental gene ME1, thereby upregulating the expression of ME1, enhancing aerobic glycolysis of ccRCC, and promoting its malignant phenotype. Furthermore, ME1 specific inhibitor could effectively repress the oncogenic functions of circME1. Taken together, our study demonstrates that the circME1/ME1 pathway is involved in ccRCC progression and sunitinib resistance development, which may be exploited for anticancer therapy.

Construction of five microRNAs prognostic markers and a prognostic model for clear cell renal cell carcinoma

Background

To determine the role of miRNA in the progression and outcome of renal clear cell carcinoma (ccRCC), establish a model for predicting outcome in patients with ccRCC and verify it using a Cox regression model. The miRNA target genes were predicted to understand their biological functions.

Methods

The microRNAs of 71 normal tissues and 545 tumor tissues were downloaded from TCGA (https://tcga-data.nci.nih.gov/tcga/). We also downloaded 537 clinical materials from this website. The miRNA difference analysis was carried out. A prognostic model was constructed using differential miRNA. The model was verified using Cox survival analysis, receiver operator characteristic (ROC), and independent predictive analysis.

Results

MiR-130b-3p, miR-365b-3p, miR-149-5p, miR-155-5p, and miR-144-5p can be used as independent prognostic indicators. We also analyzed the related functions of the target gene and found that target genes of miRNAs are involved in the signal pathways of some tumors, including cholesterol metabolism, HIF-1 signal pathway, focus adhesion, the Rap1 signal pathway, and hepatitis C.

Conclusions

The prognostic model constructed using five miRNAs is an independent and accurate factor. These miRNAs target genes are involved in regulating a variety of tumorigenesis and signal pathways. Therefore, we have reason to believe that the regulation of signal pathways by miRNA may play a critical role in the occurrence, development, and outcome of ccRCC, provide a new therapeutic target for ccRCC, and improve outcomes.

Positive feedback regulation of lncRNA PVT1 and HIF2α contributes to clear cell renal cell carcinoma tumorigenesis and metastasis

Long noncoding RNAs (lncRNAs) have been reported to exert important roles in tumors, including clear cell renal cell carcinoma (ccRCC). PVT1 is an important oncogenic lncRNA which has critical effects on onset and development of various cancers, however, the underlying mechanism of PVT1 functioning in ccRCC remains largely unknown. VHL deficiency-induced HIF2α accumulation is one of the major factors for ccRCC. Here, we identified the potential molecular mechanism of PVT1 in promoting ccRCC development by stabilizing HIF2α. PVT1 was significantly upregulated in ccRCC tissues and high PVT1 expression was associated with poor prognosis of ccRCC patients. Both gain-of-function and loss-of function experiments revealed that PVT1 enhanced ccRCC cells proliferation, migration, and invasion and induced tumor angiogenesis in vitro and in vivo. Mechanistically, PVT1 interacted with HIF2α protein and enhanced its stability by protecting it from ubiquitination-dependent degradation, thereby exerting its biological significance. Meanwhile, HIF2α bound to the enhancer of PVT1 to transactivate its expression. Furthermore, HIF2α specific inhibitor could repress PVT1 expression and its oncogenic functions. Therefore, our study demonstrates that the PVT1/ HIF2α positive feedback loop involves in tumorigenesis and progression of ccRCC, which may be exploited for anticancer therapy.

Integrated analysis of immune-related gene subtype and immune index for immunotherapy in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common type of renal cell carcinoma (RCC) with high immunogenicity. Research on immune-related gene (IRG) is of great significance in ccRCC in identifying new therapeutic targets and improving patient prognosis. In this study, the IRG patterns of ccRCC were investigated and correlated these patterns with tumor microenvironment infiltrating characteristics in immunotherapy. Moreover, an IRG score was constructed to quantify the pattern of individual tumors through the principal component analysis algorithm. Two distinct molecular subtypes (C1 and C2) were identified based on the IRGs expression profile. Subtype C1 was characterized with significantly high level of immune-checkpoint, immune score, stromal score, showed high drug sensitivity in Sorafenib, Sunitinib, Cisplatin, Vinblastine, Vinorelbine, Vorinostat, and Gemcitabine. Cytokine-cytokine receptor pathway, chemokine signaling pathway, and JAK signaling pathways were found enriched in the subtype C1 account for the poor prognosis. Subtype C2 was linked to a better survival outcome. By using the Connective Map database, subtype specific small molecular drugs identified that could facilitate the treatment of ccRCC patients. In addition, A immune index that used to evaluated the immune modification patterns and further validated in the other types RCC dataset, such as papillary renal cell carcinoma (pRCC) and chromophobe renal cell carcinoma (chRCC). Together, this study identified two distinct molecular subtypes with immune index, aid to the treatment of ccRCC and enhancing our cognition of the tumor microenvironment infiltration characterization in ccRCC immunotherapy.

Adjuvant therapy in renal cell carcinoma: Current knowledges and future perspectives

While many patients with non-metastatic renal cell carcinoma (RCC) can be cured with surgery alone, upward of 40% of patients recur in a short delay, raising the question of additional perioperative treatments. To address this clinical need, multiple trials have investigated the addition of systemic therapy after surgery in localized or locally advanced RCC. However, adjuvant systemic therapies in the past decades have provided disappointing results with only one positive study of antiangiogenic treatments. Debatable clinical benefit of adjuvant antiangiogenic tyrosine kinase inhibitors (TKIs) therapy at cost of high adverse event profiles have paved the way for development of alternative perioperative strategies, such as immune checkpoint inhibitors (ICIs). Further investigation into combination therapies with immunotherapy, neoadjuvant approaches and patient selection will be key to determining optimal adjuvant therapy regimens to improve outcomes and increase cure rates for patients with non-metastatic RCC. In this review, we extensively present the strong and weakness of the five adjuvant antiangiogenic TKI trials, highlight the main differences and discuss about the reasons of failure. We also expose the current ongoing clinical trials in the perioperative setting and provide new insights concerning the evolving landscape of the management of non-metastatic RCC.

Combination of Ipilimumab and Nivolumab in Cancers: From Clinical Practice to Ongoing Clinical Trials

Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1) are inhibitory checkpoints that are commonly seen on activated T cells and have been offered as promising targets for the treatment of cancers. Immune checkpoint inhibitors (ICIs)targeting PD-1, including pembrolizumab and nivolumab, and those targeting its ligand PD-L1, including avelumab, atezolizumab, and durvalumab, and two drugs targeting CTLA-4, including ipilimumab and tremelimumab have been approved for the treatment of several cancers and many others are under investigating in advanced trial phases. ICIs increased antitumor T cells’ responses and showed a key role in reducing the acquired immune system tolerance which is overexpressed by cancer and tumor microenvironment. However, 50% of patients could not benefit from ICIs monotherapy. To overcome this, a combination of ipilimumab and nivolumab is frequently investigated as an approach to improve oncological outcomes. Despite promising results for the combination of ipilimumab and nivolumab, safety concerns slowed down the development of such strategies. Herein, we review data concerning the clinical activity and the adverse events of ipilimumab and nivolumab combination therapy, assessing ongoing clinical trials to identify clinical outlines that may support combination therapy as an effective treatment. To the best of our knowledge, this paper is one of the first studies to evaluate the efficacy and safety of ipilimumab and nivolumab combination therapy in several cancers.

Downregulation of microRNA-15a suppresses the proliferation and invasion of renal cell carcinoma via direct targeting of eIF4E

The downregulation of microRNA-15a has been reported in several human tumors. However, its expression and functional importance in renal cell carcinoma (RCC) remain unknown. The aim of the present study was to investigate its expression, biological functions and underlying mechanisms in RCC tumorigenesis. The expression levels of miR-15a were examined by qRT-PCR in 40 RCC specimens and adjacent‑paired normal tissues. Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry and Transwell assays were used to explore the potential influence of miR-15a transfection on RCC cell proliferation, the cell cycle, cell apoptosis, and cell invasion. Luciferase reporter assays were performed to confirm the potential target of miR-15a, in combination with qRT-PCR, western blotting and immunohistochemical assays. We found that miR-15a was significantly downregulated in most RCC specimens compared with adjacent normal tissues (P<0.01). Overexpression of miR-15a inhibited cellular growth, suppressed invasion and arrested cells at the G1/G0 phase, and induced cell apoptosis in RCC cells. Luciferase assays revealed that miR-15a directly targeted the binding site of the 3'-untranslated region (3'-UTR) of eIF4E, and inhibited its expression at both mRNA and protein levels. eIF4E expression was negatively associated with miR-15a expression in RCC tissues. eIF4E overexpression treatment partially abrogated the inhibitory effect of miR-15a on cell proliferation and invasion, as well as inactivated P13K/AKT/mTOR signaling in RCC cells. In conclusion, the present study indicated that miR-15a downregulation was associated with cell proliferation and invasion by directly targeting eIF4E during RCC progression. Thus, it may serve as a potential tumor suppressor and therapeutic target for the treatment of RCC.

Secreted miR-210-3p as non-invasive biomarker in clear cell renal cell carcinoma

The most common subtype of renal cell carcinoma (RCC) is clear cell RCC (ccRCC). It accounts for 70-80% of all renal malignancies representing the third most common urological cancer after prostate and bladder cancer. The identification of non-invasive biomarkers for the diagnosis and responsiveness to therapy of ccRCC may represent a relevant step-forward in ccRCC management. The aim of this study is to evaluate whether specific miRNAs deregulated in ccRCC tissues present altered levels also in urine specimens. To this end we first assessed that miR-21-5p, miR-210-3p and miR-221-3p resulted upregulated in ccRCC fresh frozen tissues compared to matched normal counterparts. Next, we evidenced that miR-210-3p resulted significantly up-regulated in 38 urine specimens collected from two independent cohorts of ccRCC patients at the time of surgery compared to healthy donors samples. Of note, miR-210-3p levels resulted significantly reduced in follow-up samples. These results point to miR-210-3p as a potential non-invasive biomarker useful not only for diagnosis but also for the assessment of complete resection or response to treatment in ccRCC management.

Renal Tumor in Allogeneic Kidney Transplant Recipient

BACKGROUND

Malignancies will be a leading cause of mortality in renal transplant recipients in the next 20 years. Renal cell cancer (RCC) is the most common urologic cancer in kidney transplant recipients. The risk of RCC development in kidney transplant recipients is 15-100 times higher than in the general population. The purpose of the current retrospective study was to assess the frequency of nephrectomies performed because of renal tumors in the native kidneys in kidney transplant recipients in the Department of General and Transplantation Surgery at the Medical University of Warsaw between 2010 and 2014 year; the identification of kidney recipients diagnosed with RCC; and epidemiologic, clinical, and histopathological aspects associated with RCC.

PATIENTS AND METHODS

A total of 319 nephrectomies were performed in the Department of General and Transplantation Surgery at the Medical University of Warsaw between 2010 and 2014 year. Renal tumors were diagnosed in 25 renal transplant recipients.

RESULTS

Among malignant tumors, 13 cases of RCC and 1 case of post-transplant lymphoproliferative disorder (PTLD) were observed. There was no significant difference between age and duration of pretransplantation dialysis in patients with RCC and patients with benign tumors (P = .14 and P = .91, respectively). Body mass index was significantly higher in patients with RCC than in patients with benign tumors (P = .04).

CONCLUSIONS

Renal cell cancer is more common among male kidney recipients. There is a good Polish screening system allowing detection of kidney cancer in native kidney. We recommend performing periodic screening for kidney cancers to obtain an early diagnosis.

miRNA-21 promotes renal carcinoma cell invasion in a microfluidic device

MicroRNAs (miR) play important roles in cancer invasion.

Oncogenic MicroRNAs Characterization in Clear Cell Renal Cell Carcinoma

A key challenge for the improvement of clear cell renal cell carcinoma (ccRCC) management could derive from a deeper characterization of the biology of these neoplasms that could greatly improve the diagnosis, prognosis and treatment choice. The aim of this study was to identify specific miRNAs that are deregulated in tumor vs. normal kidney tissues and that could impact on the biology of ccRCC. To this end we selected four miRNAs (miR-21-5p, miR-210-3p, miR-185-5p and miR-221-3p) and their expression has been evaluated in a retrospective cohort of formalin-fixed paraffin-embedded (FFPE) tissues from 20 ccRCC patients who underwent surgical nephrectomy resection. miR-21-5p and miR-210-3p resulted the most significantly up-regulated miRNAs in this patient cohort, highlighting these onco-miRNAs as possible relevant players involved in ccRCC tumorigenesis. Thus, this study reports the identification of specific oncogenic miRNAs that are altered in ccRCC tissues and suggests that they might be useful biomarkers in ccRCC management.

Radiation therapy following targeted therapy in oligometastatic renal cell carcinoma

Up to 40% of patients with renal cell carcinoma (RCC) with initially localized disease eventually develop metastasis following nephrectomy. The current standard of care for metastatic RCC (mRCC) is targeted therapy. However, complete response remains rare. A state of oligometastatic disease may exist, in which metastases are present in a limited number of locations; such cases may benefit from metastasis-directed local therapy, based on the evidence supporting resection of limited-volume metastases, allowing for improved disease control. We retrospectively analyzed 7 cases of response of RCC metastases, in patients treated with targeted therapies followed by radiation therapy (RT) of residual metastatic lesions in Paoli-Calmettes Institute (Marseille, France). We analyzed disease response rates, response to sequential strategy, relapse at the irradiated locations and disease evolution. The median follow-up was 34.1 months (range, 19.2-54.5 months). No progression at the irradiated sites was observed. A total of 5 patients had stable disease at the irradiated locations at the last follow-up; 3 remained in complete remission at the assessment, and 2 were stable. Excellent local response and clinical benefit may be achieved without added toxicity. In conclusion, sequential therapeutic strategies with RT following systemic treatment using sunitinib appear to be highly effective in patients with progressive mRCC and prompt the conduction of further confirmatory trials.

Telmisartan induces apoptosis and regulates Bcl-2 in human renal cancer cells

It has been well-characterized that the renin-angiotensin system (RAS) physiologically regulates systemic arterial pressure. However, RAS signaling has also been shown to increase cell proliferation during malignancy, and angiotensin receptor blockers (ARBs) are able to decrease pro-survival signaling by inhibiting anti-apoptotic molecules and suppressing caspase activity. In this study, the apoptotic effects of telmisartan, a type of ARB, was evaluated using a non-cancerous human renal cell line (HEK) and a human renal cell carcinoma (RCC) cell line (786). Both types of cells were treated with telmisartan for 4 h, 24 h, and 48 h, and then were assayed for levels of apoptosis, caspase-3, and Bcl-2 using MTT assays, flow cytometry, and immunostaining studies. Analysis of variance was used to identify significant differences between these data (P < 0.05). Following the treatment of 786 cells with 100 µM and 200 µM telmisartan, a marked inhibition of cell proliferation was observed. 50 µM cisplatin also caused high inhibition of these cells. Moreover, these inhibitions were both concentration- and time-dependent (P < 0.05). Various apoptotic effects were also observed compared with control cells at the 24 h and 48 h timepoints assayed (P < 0.001). Furthermore, positive caspase-3 staining and down-regulation of Bcl-2 were detected, consistent with induction of cell death. In contrast, treatment of HEK cells with telmisartan did not produce an apoptotic effect compared with control cells at the 24 h timepoint (P > 0.05). Treatment with cisplatin promoted in HEK cells high index of apoptosis (P < 0.001). Taken together, these results suggest that telmisartan induces apoptosis via down-regulation of Bcl-2 and involvement of caspase-3 in human RCC cells.

Tumor VEGF expression correlates with tumor stage and identifies prognostically different groups in patients with clear cell renal cell carcinoma

OBJECTIVES

Vascular endothelial growth factor (VEGF) is a potent inducer of tumor angiogenesis and represents the key element in the pathogenesis of clear cell renal cell carcinoma (ccRCC). The aim of this study was to investigate the use of tumor VEGF expression as a parameter to identify tumor stage and prognostically different patient groups.

METHODS AND MATERIALS

We retrospectively collected clinical data of 137 patients treated with partial or radical nephrectomy at our institutions for organ-confined, locally advanced, and metastatic ccRCCs between 1984 and 2013. Tumor cell VEGF immunohistochemical expression was compared with pathological and clinical features including age, sex, tumor stage, and Fuhrman grade. Comparison of VEGF expression levels between tumor stages was performed via Kruskal-Wallis nonparametric test. Survival analysis was conducted via Kaplan-Meier product-limit method, and Mantel-Haenszel log-rank test was employed to compare survival among groups.

RESULTS

Median age at diagnosis was 61 years (range: 33-85 y). Tumor stage was pT1N0M0 in 67 patients (49%), pT2N0M0 in 5 (4%), and pT3N0M0 in 25 (18%), while 40 patients (29%) had metastatic tumors at diagnosis. Fuhrman nuclear grade was G1 in 22 patients (16%), G2 in 60 (44%), G3 in 33 (24%), G4 in 13 patients (9%), and unknown in 9 patients. Tumor VEGF was differentially expressed among different stages (P<0.001) and in low (G1-2) and high (G3-4) Fuhrman grade tumors (P<0.001). No significant differences were found when stratifying by sex (P = 0.06) or age (P = 0.29). Median overall survival (OS) from partial or radical nephrectomy was 161 months (range: 1-366). We observed a significantly longer OS in patients with low (<25%) vs. high (>25%) VEGF expression levels (median OS 206 vs. 65 mo, P<0.001).

CONCLUSIONS

Our data show that tumor cell VEGF expression is significantly associated with tumor stage and Fuhrman grade and is able to predict patient outcome, suggesting a potential use of this parameter in identifying prognostically different patients with ccRCC.

Temsirolimus

Temsirolimus, an ester of sirolimus (rapamycin), selectively inhibits the kinase mammalian target of rapamycin (mTOR) and consequently blocks the translation of cell cycle regulatory proteins and prevents overexpression of angiogenic growth factors. It has been found to have antitumour activity in patients with relapsed or refractory mantle cell lymphoma (MCL). In addition, patients with advanced renal cell carcinoma (RCC) and a poor prognosis who received a once-weekly intravenous (IV) infusion of temsirolimus 25 mg experienced significant survival benefits compared with patients receiving standard interferon-α (IFN-α) therapy in a large phase III clinical study. In this study, median overall survival was 10.9 versus 7.3 months and objective response rates were 8.6% in temsirolimus recipients versus 4.8% IFN-α recipient group. Temsirolimus monotherapy recipients experienced significantly fewer grade 3 or 4 adverse events and had fewer withdrawals for adverse events than patients receiving IFN-α. The role of temsirolimus in sequential and combination therapy is yet to be found.

Differential microRNA expression in renal cell carcinoma

The present study aimed to detect microRNA expression levels in the tissues and sera of patients with clear cell renal cell carcinoma (ccRCC). The association of microRNA expression with ccRCC clinical pathology was analyzed, and the potential of the microRNAs as ccRCC serum markers and the significance of their expression in the clinical diagnosis, staging, prognosis and selection of new therapeutic targets for ccRCC were discussed. Specific microRNAs were selected according to the associated literature. TaqMan quantitative polymerase chain reaction (qPCR) technology was used to determine the expression levels of selected microRNAs. miR-34a, miR-224 and miR-21 were upregulated, whereas miR-141, miR-149 and miR-429 were downregulated in the ccRCC tissues (P<0.01). The expression of miR-221 and miR-211 was not significant in the ccRCC tissues (P>0.05). miR-34a, miR-21 and miR-224 were upregulated and miR-141 was downregulated in the sera of patients with ccRCC (P<0.01), while the expression of miR-149 and miR-429 was not significant (P>0.05). The serum miR-21 expression levels were significantly correlated with the clinical staging of the patients with ccRCC (P<0.05). miR-34a, miR-21 and miR-224 are upregulated in the tissues and sera of patients with ccRCC, whereas miR-141 is downregulated. miR-21 and miR-141 are associated with ccRCC and are, thus, potential ccRCC serum markers.

Clear cell renal cell carcinoma associated microRNA expression signatures identified by an integrated bioinformatics analysis

Background

Clear cell renal cell carcinoma (ccRCC) represents the most invasive and common adult kidney neoplasm. Mounting evidence suggests that microRNAs (miRNAs) are important regulators of gene expression. But their function in tumourigenesis in this tumour type remains elusive. With the development of high throughput technologies such as microarrays and NGS, aberrant miRNA expression has been widely observed in ccRCC. Systematic and integrative analysis of multiple microRNA expression datasets may reveal potential mechanisms by which microRNAs contribute to ccRCC pathogenesis.

Methods

We collected 5 public microRNA expression datasets in ccRCC versus non-matching normal renal tissues from GEO database and published literatures. We analyzed these data sets with an integrated bioinformatics framework to identify expression signatures. The framework incorporates a novel statistic method for abnormal gene expression detection and an in-house developed predictor to assess the regulatory activity of microRNAs. We then mapped target genes of DE-miRNAs to different databases, such as GO, KEGG, GeneGo etc, for functional enrichment analysis.

Results

Using this framework we identified a consistent panel of eleven deregulated miRNAs shared by five independent datasets that can distinguish normal kidney tissues from ccRCC. After comparison with 3 RNA-seq based microRNA profiling studies, we found that our data correlated well with the results of next generation sequencing. We also discovered 14 novel molecular pathways that are likely to play a role in the tumourigenesis of ccRCC.

Conclusions

The integrative framework described in this paper greatly improves the inter-dataset consistency of microRNA expression signatures. Consensus expression profile should be identified at pathway or network level to address the heterogeneity of cancer. The DE-miRNA signature and novel pathways identified herein could provide potential biomarkers for ccRCC that await further validation.

Evaluation of cancer treatment in the abdomen: Trends and advances

Response evaluation in Oncology has relied primarily on change in tumor size. Inconsistent results in the prediction of clinical outcome when size based criteria are used and the increasing role of targeted and loco-regional therapies have led to the development of new methods of response evaluation that are unrelated to change in tumor size. The goals of this review are to expose briefly the size based criteria and to present the non-size based approaches that are currently applicable in the clinical setting. Other paths that are still being explored are not discussed in details.

Effects of oleic acid on cell proliferation through an integrin-linked kinase signaling pathway in 786-O renal cell carcinoma cells

An increased risk of renal cell carcinoma (RCC) has been linked with obesity and metabolic syndrome. However, the mechanisms by which lipid metabolic disorders affect the development of RCC remain unclear and highly controversial. Integrin-linked kinase (ILK) is a serine/threonine protein kinase involved in the regulation of tumor cell growth and angiogenesis. In the present study, the effect of free fatty acids in the promotion of RCC progression was investigated by upregulating ILK. Results of the MTT assay indicated that treatment of 786-O cells with oleic acid induced a concentration-dependent increase in cell viability. Flow cytometry analysis revealed that the effect of oleic acid on cell apoptosis was not significant. Following treatment with oleic acid, the expression of ILK, phospho-Akt and G protein-coupled receptor 40 (GPR40) was increased in 786-O cells. These effects were reversed when the expression of ILK was downregulated using specific small interfering RNA. These results indicate that free fatty acids are associated with the development of renal cell carcinoma via activation of the GPR40/ILK/Akt pathway, revealing a novel mechanism for the correlation between metabolic disturbance and renal carcinoma.

Survival analysis of 254 patients after manifestation of spinal metastases: evaluation of seven preoperative scoring systems

STUDY DESIGN

Retrospective study.

OBJECTIVE

This study analyzed the predictive value of the scoring systems of Bauer, Bauer modified, Tokuhashi, Tokuhashi revised, Tomita, van der Linden, and Sioutos as well as the parameters included in these systems.

SUMMARY OF BACKGROUND DATA

Metastases of the spinal column are a common manifestation of advanced cancer. Severe pain, pathologic fracture, and neurologic deficit due to spinal metastases need adequate treatment. Besides oncologic aspects and quality of life, treatment decisions should also include the survival prognosis.

METHODS

Two hundred fifty-four patients with confirmed spinal metastases were investigated retrospectively (treatment 1998-2006; 62 underwent surgery and 192 had conservative treatment only). Factors related to survival, such as primary tumor, general condition (Karnofsky Performance Status Scale), neurologic deficit, number of spinal and extraspinal bone metastases, visceral metastases, and pathologic fracture, were analyzed. The survival period was calculated from date of diagnosis of the spinal metastases to date of death or last follow-up (minimum follow-up: 12 months). For statistical analysis, univariate and stepwise multivariate Cox regression analyses were performed.

RESULTS

Median overall survival for all patients was 10.6 months. The following factors showed significant influence on survival in multivariate analysis: primary tumor (P < 0.0001), status of visceral metastases (P < 0.0001), and systemic therapy (P < 0.0001). Using the recommended group assignment for each system, only Bauer and Bauer modified showed significant results for the distinction between good, moderate, and poor prognosis. The other systems failed to distinguish significantly between good and moderate prognosis. The hazard ratio of the absolute score of all analyzed systems was, however, statistically significant, with a better score leading to lower risk of death.

CONCLUSION

According to this analysis, the Bauer and the Bauer modified scores are the most reliable systems for predicting survival. Since the Bauer modified score furthermore consists of only four positive prognostic factors, we emphasize its impact and simplicity.

Combination of gemcitabine and doxorubicin in rapidly progressive metastatic renal cell carcinoma and/or sarcomatoid renal cell carcinoma

BACKGROUND/AIMS

Metastatic renal cell carcinoma (mRCC) can be rapidly progressive when tumors exhibit sarcomatoid or Fuhrman grade 4 features. Efficacy of gemcitabine (Gem) with doxorubicin (Dox) in sarcomatoid or rapidly progressive mRCC has been reported. We retrospectively evaluated Gem + Dox in a consecutive cohort of this particular patient population.

PATIENTS AND METHODS

Patients had an Eastern Cooperative Oncology Group performance status of 2 or more and rapidly progressive mRCC or mRCC with sarcomatoid features. Gem (1,500 mg/m(2)) and Dox (50 mg/m(2)) were given every 2 weeks with granulocyte colony-stimulating factor.

RESULTS

Twenty-nine patients were treated. Sarcomatoid features were predominant in 6 patients, while 14 tumors were Fuhrman grade 4. All patients had progressive mRCC within 4 months. No grade 4 toxicity or drug-related death was reported. One partial response (7 months), 1 mixed response, and 14 stable diseases (≥4 months for 9 patients) were observed and no response was seen in sarcomatoid tumors. The median disease-free survival was 3.7 months (≥6 months for 8 patients) and the median overall survival was 4.8 months (>12 months for 5 patients).

CONCLUSION

This study showed a lower response rate than previously reported. Nevertheless, some patients had prolonged survival outcomes. This combination could be an option in sarcomatoid histology (NCCN guidelines) or rapidly progressive disease, but this population represents an unmet medical need.

MicroRNAs and their target gene networks in renal cell carcinoma

MicroRNAs (miRNAs) are non-protein-coding short single stranded RNAs in the size range 19-25 nucleotides that are associated with gene regulation at the transcriptional and translational level. Recent studies have proved that miRNAs play important roles in a large number of biological processes, including cellular differentiation, proliferation, apoptosis, etc. Changes in their expression were found in a variety of human cancers, including renal cell carcinoma pathogenesis. Specific miRNA alterations were associated with key pathogenetic mechanisms of renal cell carcinoma like hypoxia or epithelial-mesenchymal transition. In this review, we summarize the current knowledge of miRNA functions in renal cell carcinoma with an emphasis on miRNAs potential to serve as a powerful biomarker of disease and a novel therapeutic target in oncology.

Genetic variations in microRNA-related genes are associated with survival and recurrence in patients with renal cell carcinoma

We took a polygenic approach to evaluate the effects of 41 potentially functional single-nucleotide polymorphisms (SNPs) in microRNAs (miRNAs)-related genes on survival and recurrence among renal cell carcinoma (RCC) patients. During a median follow-up of 21.8 months, among 316 RCC patients, 64 died and 56 developed recurrence. In single-SNP analysis, we identified seven SNPs significantly associated with RCC survival and five SNPs with recurrence. The most significant associations were SNPs in GEMIN4 with the variant alleles of both rs7813 and rs910925 associated with 1.74-fold [95% confidence interval (CI) = 1.15-2.62] increased risk of death, whereas the variant allele of rs3744741 conferred a decreased risk of death [hazard ratio (HR) = 0.39; 95% CI = 0.19-0.77]. Several SNPs belonging to the pre-miRNA and were identified to be significantly associated with RCC recurrence. Haplotypes of DICER and DROSHA were also associated with altered patient survival and recurrence. More importantly, we observed cumulative effects of multiple SNPs on RCC survival. Compared with subjects carrying zero to two unfavorable genotypes, those carrying three to five and six and more unfavorable genotypes had an increased risk of death with a HR of 2.49 (95% CI = 1.24-5.00) and 6.66 (95% CI = 2.49-17.86), respectively, with significant dose-response trend (P for trend<0.001). As the first study of miRNA-related genetic polymorphisms on RCC clinical outcome, our results strongly suggested that miRNA-related SNPs may impact the recurrence and survival in RCC patients. Future investigation in larger populations and functional characterizations are necessary to validate these results.

Vascular endocan (ESM-1) is markedly overexpressed in clear cell renal cell carcinoma

AIMS

In kidney cancer, new anti-angiogenic therapies have emerged requiring parameters of effectiveness. The aim was to analyse the expression of endocan or endothelial cell-specific molecule-1, which is a proteoglycan up-regulated in presence of pro-angiogenic factors.

METHOD AND RESULTS

We investigated 44 renal clear cell carcinomas (RCC) and 25 papillary carcinomas (PC). Circulating endocan was detected by enzyme-linked immunosorbent assays (ELISA) in 14 patients with RCC, in eight with PC and in 15 healthy volunteers. Endocan was detected by immunohistochemistry in endothelial cells in almost all the cases of RCC without immunoreactivity in tumour cells. In PC, only 5/25 tumours exhibited weak immunoreactivity. Reverse transcriptase-polymerase chain reaction study confirmed that endocan levels were strongly increased in RCC. Endocan was also detected by ELISA at levels from 3- to 10-fold higher in the sera of patients with RCC. In vitro, addition of sunitinib prevented the release of endocan in human umbilical vascular endothelial cells when induced by vascular endothelial growth factor.

CONCLUSIONS

Our results showed that endocan is overexpressed in patients with RCC. Endocan could therefore appear as a marker of interest in the follow-up and may be a potential parameter to monitor the tumour response to anti-angiogenic therapeutics.

Safety and efficacy results of the advanced renal cell carcinoma sorafenib expanded access program in North America

BACKGROUND

The Advanced Renal Cell Carcinoma Sorafenib (ARCCS) program made sorafenib available to patients with advanced renal cell carcinoma (RCC) before regulatory approval.

METHODS

In this nonrandomized, open-label expanded access program, 2504 patients from the United States and Canada were treated with oral sorafenib 400 mg twice daily. Safety and efficacy were explored overall and in subgroups of patients including those with no prior therapy, nonclear cell (nonclear cell) RCC, brain metastases, prior bevacizumab treatment, and elderly patients. Sorafenib was approved for RCC 6 months after study initiation, at which time patients with no prior therapy or with nonclear cell RCC could enroll in an extension protocol for continued assessment for a period of 6 months.

RESULTS

The most common grade > or =2 drug-related adverse events were hand-foot skin reaction (18%), rash (14%), hypertension (12%), and fatigue (11%). In the 1891 patients evaluable for response, complete response was observed in 1 patient, partial response in 67 patients (4%), and stable disease for at least 8 weeks in 1511 patients (80%). Median progression-free survival in the extension population was 36 weeks (95% confidence interval [CI], 33-45 weeks; censorship rate, 56%); median overall survival in the entire population was 50 weeks (95% CI, 46-52 weeks; censorship rate, 63%). The efficacy and safety results were similar across the subgroups.

CONCLUSIONS

Sorafenib 400 mg twice daily demonstrated activity and a clinically acceptable toxicity profile in all patient subsets enrolled in the ARCCS expanded access program (clinicaltrials.gov identifier: NCT00111020).

Temsirolimus

Temsirolimus, an ester of sirolimus (rapamycin), selectively inhibits the kinase mammalian target of rapamycin and consequently blocks the translation of cell cycle regulatory proteins and prevents overexpression of angiogenic growth factors. Patients with advanced renal cell carcinoma (RCC) and a poor prognosis who received a once-weekly intravenous (IV) infusion of temsirolimus 25 mg, experienced significant survival benefits when compared with patients receiving standard interferon-alpha (IFNalpha) therapy in a large phase III clinical study. In this study, median overall survival was 10.9 vs. 7.3 months and objective response rates were 8.6% in temsirolimus recipients vs. 4.8% IFNalpha recipient group.Temsirolimus monotherapy recipients experienced significantly fewer grade 3 or 4 adverse events and had fewer withdrawals for adverse events than patients receiving IFNalpha.

A phase II study of sunitinib in Japanese patients with metastatic renal cell carcinoma: insights into the treatment, efficacy and safety

OBJECTIVE

This study aims to assess the efficacy and safety of sunitinib in Japanese patients with metastatic renal cell carcinoma (RCC).

METHODS

Fifty-one Japanese patients with prior nephrectomy, 25 treatment-naive patients (first-line group) and 26 cytokine-refractory patients (pretreated group) were enrolled in this phase II trial. Patients received sunitinib 50 mg orally, once daily, in repeated 6-week cycles (4 weeks on treatment, 2 weeks off). The primary endpoint was RECIST-defined objective response rate (ORR) with tumour assessments every 6 weeks via computed tomography or magnetic resonance imaging. Toxicity was assessed regularly. In the primary efficacy analysis of the intent-to-treat (ITT) population, ORR and 95% confidence interval were calculated based on independent review. Secondary time-to-event endpoints, such as progression-free survival (PFS), were estimated using the Kaplan-Meier method.

RESULTS

In the ITT population, ORR was 48.0% in the first-line group (after a median 4 cycles), 46.2% in the pretreated group (5 cycles) and 47.1% overall, with median times to tumour response of 7.1, 10.7 and 10.0 weeks, respectively. Median PFS was 46.0, 33.6 and 46.0 weeks, respectively. The most common treatment-related grade 3/4 adverse events and laboratory abnormalities were fatigue (20%), hand-foot syndrome (14%) and hypertension (12%), decreased platelet count (55%), decreased neutrophil count (51%), increased lipase (39%) and decreased lymphocyte count (33%).

CONCLUSIONS

In Japanese patients with RCC, sunitinib is consistently effective and tolerable with similar risk/benefit as that in Western patients, though there was a trend toward greater antitumour efficacy and higher incidence of haematological adverse events in Japanese patients.

Genome-wide profiling of chromosomal alterations in renal cell carcinoma using high-density single nucleotide polymorphism arrays

The identification of genetic aberrations may help understand the mechanisms of tumorigenesis and has important implications in diagnosis, prognosis and treatment. We applied Illumina's 317K high-density single nucleotide polymorphism (SNP) arrays to profile chromosomal aberrations in clear cell renal cell carcinoma (ccRCC) from 80 patients and analyzed the association of LOH/amplification events with clinicopathological characteristics and telomere length. The most common loss of heterozygosity (LOH) were 3p (69 cases) including 38 whole 3p arm losses, 30 large fragment LOH (spanning 3p21-36), and 1 interstitial LOH (spanning 3p12-14, 3p21-22, 3p24.1-24.2 and 3p24.3), followed by chromosome losses at 8p12-pter, 6q23.3-27, 14q24.1-qter, 9q32-qter, 10q22.3-qter, 9p13.3-pter, 4q28.3-qter and 13q12.1-21.1. We also found several smallest overlapping regions of LOH that contained tumor suppressor genes. One smallest LOH in 8p12 had a size of 0.29 Mb and only contained one gene (NRG1). The most frequent chromosome gains were at 5q (32 cases), including 10 whole 5q amplification, 21 large amplifications encompassing 5q32-ter and 1 focal amplification in 5q35.3 (0.42 Mb). The other common chromosome gains were 1q25.1-qter, 7q21.13-qter, 8q24.12-qter and whole 7p arm. Significant associations of LOH at 9p, 9q, 14q and 18q were observed with higher nuclear grade. Significant associations with tumor stage were observed for LOH at 14q, 18p and 21q. Finally, we found that tumors with LOH at 2q, 6p, 6q, 9p, 9q and 17p had significantly shorter telomere length than those without LOH. This is the first study to use Illumina's SNP-CGH array that provides a close estimate of the size and frequency of chromosome LOH and amplifications of ccRCC. The identified regions and genes may become diagnostic and prognostic biomarkers as well as potential targets of therapy.

T cell-based immunotherapy of metastatic renal cell carcinoma: modest success and future perspective

Metastatic renal cell carcinoma (MRCC) remains a challenging malignancy to treat. Cancer immunotherapies have been extensively explored in melanoma and RCC as they poorly respond to conventional cytotoxic agents but show responses to a variety of immunologic agents. The recent considerable success of T cell-based immunotherapy in melanoma warrants further efforts to apply this treatment to other cancers including MRCC. Although RCC is an immunosensitive cancer, similar attempts in MRCC have shown a very limited success. In this review, we summarize the clinical data on T cell-based immunotherapies for MRCC showing the modest success that has been achieved to date. More importantly, we discuss potential strategies for improving its efficacy for the treatment of MRCC in light of the important achievements for treating metastatic melanoma. In particular, the growing evidence of success by combining expanded tumor-infiltrating lymphocytes with lymphodepletion merits investigation in MRCC. Identifying new RCC-associated antigens, optimized methods, and conditions for detection, isolation, and/or modification and expansion of tumor-specific T cells are all important strategies to be pursued for improving T cell-based immunotherapy of MRCC.

Brain-type and liver-type fatty acid-binding proteins: new tumor markers for renal cancer?

BACKGROUND

Renal cell carcinoma (RCC) is the most common renal neoplasm. Cancer tissue is often characterized by altered energy regulation. Fatty acid-binding proteins (FABP) are involved in the intracellular transport of fatty acids (FA). We examined the level of brain-type (B) and liver-type (L) FABP mRNA and the protein expression profiles of both FABPs in renal cell carcinoma.

METHODS

Paired tissue samples of cancerous and noncancerous kidney parts were investigated. Quantitative RT-PCR, immunohistochemistry and western blotting were used to determine B- and L-FABP in tumor and normal tissues. The tissue microarray (TMA) contained 272 clinico-pathologically characterized renal cell carcinomas of the clear cell, papillary and chromophobe subtype. SPSS 17.0 was used to apply crosstables (chi2-test), correlations and survival analyses.

RESULTS

B-FABP mRNA was significantly up-regulated in renal cell carcinoma. In normal tissue B-FABP mRNA was very low or often not detectable. RCC with a high tumor grading (G3 + G4) showed significantly lower B-FABP mRNA compared with those with a low grading (G1 + G2). Western blotting analysis detected B-FABP in 78% of the cases with a very strong band but in the corresponding normal tissue it was weak or not detectable. L-FABP showed an inverse relationship for mRNA quantification and western blotting. A strong B-FABP staining was present in 52% of the tumor tissues contained in the TMA. In normal renal tissue, L-FABP showed a moderate to strong immunoreactivity in proximal tubuli. L-FABP was expressed at lower rates compared with the normal tissues in 30.5% of all tumors. There was no correlation between patient survival times and the staining intensity of both FABPs.

CONCLUSION

While B-FABP is over expressed in renal cell carcinoma in comparison to normal renal tissues L-FABP appears to be reduced in tumor tissue. Although the expression behavior was not related to the survival outcome of the RCC patients, it can be assumed that these changes indicate fundamental alterations in the fatty metabolism in the RCC carcinogenesis. Further studies should identify the role of both FABPs in carcinogenesis, progression and with regard to a potential target in RCC.

Intradural spinal metastasis of renal cell cancer. Report of a case and review of 26 published cases

Metastatic disease in the intradural compartment of the spine is a rare manifestation of cancer. We report the case of an 82-year-old patient with an intradural, extramedullary metastasis of renal cell carcinoma in the cervical spine. A literature search for intradural spinal metastases of renal cell carcinoma yielded a total of 26 further cases. 18 patients had sporadic renal cell carcinoma, and 9 patients had von Hippel-Lindau disease (VHL) in which the metastases of the renal cell carcinoma were embedded within spinal haemangioblastomas. Patients presented with paresis, back pain, altered sensation or, less frequently, bladder dysfunction. Intradural spinal metastases were diagnosed at an earlier age in VHL patients than in sporadic cases (mean 43 +/- 5 years vs. 60 +/- 14.5 years). The metastasis was surgically removed in 81% of patients. Pain improved in all patients, paresis in 90%, hypaesthesia in 38% and bladder dysfunction in 50%. Death occurred as a result of systemic cancer progression. 93% of patients in the sporadic renal cell cancer group died within 1.5 years, whereas two thirds of the VHL patients were alive after 2 years.

Management of metastatic renal cell carcinoma: current trends

Renal cell carcinoma is one of the common malignancies of the genitourinary tract. In approximately one third of patients, distant metastases are present at the time of initial diagnosis and in another third, the tumor will recur even after nephrectomy with a curative intent. Renal cell carcinoma is resistant to all conventional treatment modalities of cancer, including radiotherapy and chemotherapy. We review the management of patients with metastatic renal cell carcinoma in the era of the new targeted therapeutic agents.

Phase I trial of sunitinib malate plus interferon-alpha for patients with metastatic renal cell carcinoma

BACKGROUND

Sunitinib malate is an oral, multitargeted tyrosine kinase inhibitor that has demonstrated superior efficacy over interferon (IFN)-alpha in a phase III trial in first-line, metastatic renal cell carcinoma (RCC). Herein, we report the results of a phase I dose-finding study of sunitinib in combination with IFN-alpha as first-line treatment in patients with metastatic RCC.

PATIENTS AND METHODS

Treatment-naive patients with clear-cell metastatic RCC received sunitinib at a starting dose of 50 mg or 37.5 mg orally once daily in 6-week cycles (schedule 4/2) plus IFN-alpha at a starting dose of 3 MU subcutaneously 3 times a week, with weekly intrapatient dose escalation to a maximum of 9 MU as tolerated. Patients who did not tolerate either drug received lower doses of either or had dose interruptions.

RESULTS

Twenty-five patients were enrolled; their median age was 64 years (range, 45-77 years). All patients experienced grade 3/4 treatment-emergent adverse events; the most common were neutropenia, fatigue, and thrombocytopenia. After a median of 4 cycles (range, 1-9 cycles), 3 patients (12%) had a partial response, and 20 (80%) had stable disease.

CONCLUSION

Although reduced starting doses were tolerated (37.5 mg for sunitinib and 3 MU for IFN-alpha), even these lower doses might not be well tolerated for long-term treatment of patients with metastatic RCC. Based on historical data, sunitinib on schedule 4/2 appears to be more effective as single-agent therapy. Further study of sunitinib plus IFN-alpha on this schedule is not being pursued in RCC.