Epidemiologic and socioeconomic burden of metastatic renal cell carcinoma (mRCC): a literature review

Management of metastatic renal cell carcinoma - mini review

The management of metastatic renal cell carcinoma (mRCC) has evolved considerably in the last decade. A number of different systemic molecular targeted agents that have been recently approved have improved the survival of patients with mRCC. This mini-review focuses on the implementation of multi-modality therapy in the management of mRCC and the approved indications of the various available novel agents. These novel agents have expanded our armamentarium and improved clinical outcomes of this challenging disease that has considerable biological heterogeneity and clinical variability.

MicroRNA Expression Profiling in Clear Cell Renal Cell Carcinoma: Identification and Functional Validation of Key miRNAs

OBJECTIVE

This study aims to profile dysregulated microRNA (miRNA) expression in clear cell renal cell carcinoma (ccRCC) and to identify key regulatory miRNAs in ccRCC.

METHODS AND RESULTS

miRNA expression profiles in nine pairs of ccRCC tumor samples at three different stages and the adjacent, non-tumorous tissues were investigated using miRNA arrays. Eleven miRNAs were identified to be commonly dysregulated, including three up-regulated (miR-487a, miR-491-3p and miR-452) and eight down-regulated (miR-125b, miR-142-3p, miR-199a-5p, miR-22, miR-299-3p, miR-29a, miR-429, and miR-532-5p) in tumor tissues as compared with adjacent normal tissues. The 11 miRNAs and their predicted target genes were analyzed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and three key miRNAs (miR-199a-5p, miR-22 and miR-429) were identified by microRNA-gene network analysis. Dysregulation of the three key miRNAs were further validated in another cohort of 15 ccRCC samples, and the human kidney carcinoma cell line 786-O, as compared with five normal kidney samples. Further investigation showed that over-expression of miR-199a-5p significantly inhibited the invasion ability of 786-O cells. Luciferase reporter assays indicated that miR-199a-5p regulated expression of TGFBR1 and JunB by directly interacting with their 3' untranslated regions. Transfection of miR-199a-5p successfully suppressed expression of TGFBR1 and JunB in the human embryonic kidney 293T cells, further confirming the direct regulation of miR-199a-5p on these two genes.

CONCLUSIONS

This study identified 11 commonly dysregulated miRNAs in ccRCC, three of which (miR-199a-5p, miR-22 and miR-429) may represent key miRNAs involved in the pathogenesis of ccRCC. Further studies suggested that miR-199a-5p plays an important role in inhibition of cell invasion of ccRCC cells by suppressing expression of TGFBR1 and JunB.

Honokiol suppresses metastasis of renal cell carcinoma by targeting KISS1/KISS1R signaling

Renal cell carcinoma (RCC) is a common urological cancer worldwide and is known to have a high risk of metastasis, which is considered responsible for more than 90% of cancer associated deaths. Honokiol is a small-molecule biphenol isolated from Magnolia spp. bark and has been shown to be a potential anticancer agent involved in multiple facets of signal transduction. In this study, we demonstrated that honokiol inhibited the invasion and colony formation of highly metastatic RCC cell line 786-0 in a dose-dependent manner. DNA-microarray data showed the significant upregulation of metastasis-suppressor gene KISS1 and its receptor, KISS1R. The upregulation was confirmed by qRT-PCR analysis. Overexpression of KISS1 and KISS1R was detected by western blotting at the translation level as well. Of note, the decreased invasive and colonized capacities were reversed by KISS1 knockdown. Taken together, the results first indicate that activation of KISS1/KISS1R signaling by honokiol suppresses multistep process of metastasis, including invasion and colony formation, in RCC cells 786-0. Honokiol may be considered as a natural agent against RCC metastasis.

IL8 polymorphisms and overall survival in pazopanib- or sunitinib-treated patients with renal cell carcinoma

BACKGROUND

We evaluated germline single nucleotide polymorphisms (SNPs) for association with overall survival (OS) in pazopanib- or sunitinib-treated patients with advanced renal cell carcinoma (aRCC).

METHODS

The discovery analysis tested 27 SNPs within 13 genes from a phase III pazopanib trial (N=241, study 1). Suggestive associations were then pursued in two independent datasets: a phase III trial (COMPARZ) comparing pazopanib vs sunitinib (N=729, study 2) and an observational study of sunitinib-treated patients (N=89, study 3).

RESULTS

In study 1, four SNPs showed nominally significant association (P≤0.05) with OS; two of these SNPs (rs1126647, rs4073) in IL8 were associated (P≤0.05) with OS in study 2. Because rs1126647 and rs4073 were highly correlated, only rs1126647 was evaluated in study 3, which also showed association (P≤0.05). In the combined data, rs1126647 was associated with OS after conservative multiple-test adjustment (P=8.8 × 10(-5); variant vs reference allele hazard ratio 1.32, 95% confidence interval: 1.15-1.52), without evidence for heterogeneity of effects between studies or between pazopanib- and sunitinib-treated patients.

CONCLUSIONS

Variant alleles of IL8 polymorphisms are associated with poorer survival outcomes in pazopanib- or sunitinib-treated patients with aRCC. These findings provide insight in aRCC prognosis and may advance our thinking in development of new therapies.

High expression of interleukin-11 is an independent indicator of poor prognosis in clear-cell renal cell carcinoma

Interleukin-11 (IL-11), a member of the IL-6 family of cytokines, exerts pleiotropic oncogenic activities by stimulating angiogenesis and metastasis in many cancer types. The present study aims to evaluate the impact of IL-11 expression on recurrence and mortality of patients with clear-cell renal cell carcinoma (ccRCC). We retrospectively enrolled 193 ccRCC patients undergoing nephrectomy at a single center. Clinicopathologic features, recurrence-free survival (RFS) and overall survival (OS) were recorded. IL-11 intensity was assessed by immunohistochemistry in tumor specimens. The Kaplan–Meier method was applied to compare survival curves. Cox regression models were used to analyze the impact of prognostic factors on RFS and OS. The concordance index (C-index) was calculated to assess predictive accuracy. High IL-11 expression is associated with increased risk of recurrence and poor survival for ccRCC patients (P < 0.001 and P < 0.001, respectively), especially those with early-stage disease (TNM stage I + II). Multivariate analyses confirmed that IL-11 expression was an independent prognostic factor for RFS and OS (P = 0.006 and P = 0.008, respectively). The predictive accuracy of well-established prognostic models was improved when IL-11 expression was integrated. In conclusion, high IL-11 expression is an independent predictor of poor prognosis in ccRCC patients. It may help identify patients who could benefit from additional treatments and closer follow up.

Downregulation of tNASP inhibits proliferation through regulating cell cycle-related proteins and inactive ERK/MAPK signal pathway in renal cell carcinoma cells

Nuclear auto-antigenic sperm protein (NASP), initially described as a highly auto-immunogenic testis and sperm-specific protein, is a histone chaperone that is proved to present in all dividing cells. NASP has two splice variants: testicular NASP (tNASP) and somatic form of NASP (sNASP). Only cancer, germ, transformed, and embryonic cells have a high level of expression of the tNASP. Up to now, little has been known about tNASP in renal cell carcinoma (RCC). In the present study, the molecular mechanism of tNASP in RCC was explored. The expression level of tNASP in 16 paired human RCC specimens was determined. Downregulation of tNASP by small interfering RNA (siRNA) was transfected in RCC cell lines. The effect of downregulation of tNASP by siRNA on cell colony formation and proliferation was examined by colony formation assay and CCK-8 assay, cell cycle was analyzed by flow cytometry, and the expression of cyclin D1 and P21 were detected by Western blotting. ERK/MAPK signaling was also analyzed. tNASP has a relative high expression level in human RCC tissues. Via upregulation of P21 and downregulation of cyclinD1, silence of tNASP can inhibit cell proliferation, which induces cell cycle arrest. Furthermore, ERK signaling pathway is confirmed to mediate the regulation of cell cycle-related proteins caused by silence of tNASP. Our research demonstrates that knockdown of tNASP effectively inhibits the proliferation and causes G1 phase arrest through ERK/MAPK signal pathway.

Targeting Integrin-Linked Kinase Suppresses Invasion and Metastasis through Downregulation of Epithelial-to-Mesenchymal Transition in Renal Cell Carcinoma

Renal cell carcinoma (RCC) is the most common malignancy in the kidney. Antiangiogenic targeted therapies inhibit the progression of RCC, but have limited impacts on invasion or metastasis of tumor cells. Integrin-linked kinase (ILK) is a serine/threonine kinase implicated in the regulation of cell growth/survival, cell-cycle progression, epithelial-mesenchymal transition (EMT), invasion/migration, and angiogenesis. However, the role of ILK in RCC has not been evaluated. We investigated the role of ILK on cancer progression and metastasis and the therapeutic potential of ILK inhibition in RCC. Our investigation reveals that ILK is expressed at a low level in normal cells and low-stage RCC cells and is highly expressed in advanced and metastatic cells. Caki-1, a metastatic RCC cell line, showed higher expression of molecular EMT markers, including Snail and Zeb1, but decreased activity of GSK3β. Knockdown of ILK using small interference (si)-ILK minimally inhibited tumor proliferation and cell-cycle progression was not significantly affected. However, ILK knockdown suppressed the formation of stress fibers and focal adhesions and impeded phenotypic EMT markers, including cell migration and invasion, in Caki-1 and UMRC-3 cells. Finally, in vivo knockdown of ILK suppressed the progression, invasion, and metastasis of primary RCC in nude mice by downregulation of EMT markers (Snail, Zeb1, vimentin, and E-cadherin). Our results show that ILK may be essential for invasion and metastasis in RCC and regulates vimentin and E-cadherin expression by regulating the EMT-related transcription factors Snail and Zeb1. These results suggest that ILK may be a potential target in RCC.

Pharmacogenomic biomarkers for personalized cancer treatment

Personalized medicine involves the selection of the safest and most effective pharmacological treatment based on the molecular characteristics of the patient. In the case of anticancer drugs, tumour cell alterations can have a great impact on drug activity and, in fact, most biomarkers predicting response originate from these cells. On the other hand, the risk of developing severe toxicity may be related to the genetic background of the patient. Thus, understanding the molecular characteristics of both the tumour and the patient, and establishing their relation with drug outcomes will be critical for the identification of predictive biomarkers and to provide the basis for individualized treatments. This is a complex scenario where multiple genes as well as pathophysiological and environmental factors are important; in addition, tumours exhibit large inter- and intraindividual variability in space and time. Against this background, the huge amounts of biological and genetic data generated by the high-throughput technologies will facilitate pharmacogenomic progress, suggest novel druggable molecules and support the design of future strategies aimed at disease control. Here, we will review the current challenges and opportunities for pharmacogenomic studies in oncology, as well as the clinically established biomarkers. Lung and renal cancer, two areas in which huge progress has been made in the last decade, will be used to illustrate advances in personalized cancer treatment; we will review EGFR mutation as the paradigm of targeted therapies in lung cancer, and discuss the dissection of lung cancer into clinically relevant molecular subsets and novel advances that suggest an important role of single nucleotide polymorphisms in the response to antiangiogenic agents, as well as the challenges that remain in these fields. Finally, we will present new approaches and future prospects for personalizing medicine in oncology.

Renal Cell Carcinoma: Delayed Metachronous Metastases to Parotid and Cerebellum

PURPOSE

The purpose of this report is to describe a rare case of delayed metachronous isolated metastases of renal cell carcinoma (RCC) to the parotid gland and the cerebellum. The metastases occurred more than a decade after treatment of the primary tumor without any other systemic involvement. In addition, the potential differential diagnosis of the parotid mass based on presentation and imaging is discussed.

MATERIALS AND METHODS

An 83-year-old man presented for evaluation and treatment of a rapidly growing mass at the right parotid region. He had a history of RCC resection 10 years before this presentation and had no evidence of persistent disease at the primary site. The diagnosis of metastatic RCC was made after fine-needle aspiration biopsy examination of the mass. The patient underwent superficial parotidectomy for resection of the tumor. Approximately 1.5 years later, he complained of loss of balance. Further investigation disclosed a cerebellar mass that at biopsy examination was found to represent RCC. He underwent stereotactic ablation of the mass. He currently remains free of disease at the primary site and the parotid and without further known brain metastases.

RESULTS

This report presents the 29th case of a solitary parotid mass consistent with metastatic RCC 10 years after successful treatment of the primary RCC. Approximately 1.5 years later, the patient presented with new-onset loss of balance. Further investigation disclosed a mass to the cerebellum consistent with metastatic RCC. This case is unique because the brain involvement occurred extremely late, 11.5 years after successful treatment of primary RCC and 1.5 years after resection of a metastatic RCC to the parotid, and without any evidence of other metastases.

CONCLUSIONS

Late distant metastases of RCC are not uncommon and patients require life surveillance follow-up, but such late presentation of metachronous metastases without systemic disease progression is unique. The patterns of metastases of RCC are not clearly defined and this diagnosis should be considered, especially in patients with relevant history.

High mobility group box 1 protein is methylated and transported to cytoplasm in clear cell renal cell carcinoma

BACKGROUND

The high mobility group box 1 (HMGB1) protein is a widespread nuclear protein present in most cell types. It typically locates in the nucleus and functions as a nuclear cofactor in transcription regulation. However, HMGB1 can also localize in the cytoplasm and be released into extracellular matrix, where it plays critical roles in carcinogenesis and inflammation. However, it remains elusive whether HMGB1 is relocated to cytoplasm in clear cell renal cell carcinoma (ccRCC).

METHODS

Nuclear and cytoplasmic proteins were extracted by different protocols from 20 ccRCC samples and corresponding adjacent renal tissues. Western blotting and immunohistochemistry were used to identify the expression of HMGB1 in ccRCC. To elucidate the potential mechanism of HMGB1 cytoplasmic translocation, HMGB1 proteins were enriched by immunoprecipitation and analyzed by mass spectrometry (MS).

RESULTS

The HMGB1 protein was overexpressed and partially localized in cytoplasm in ccRCC samples (12/20, 60%, p<0.05). Immunohistochemistry results indicated that ccRCC of high nuclear grade possess more HMGB1 relocation than those with low grade (p<0.05). Methylation of HMGB1 at lysine 112 in ccRCC was detected by MS. Bioinformatics analysis showed that post-translational modification might affect the binding ability to DNA and mediate its translocation.

CONCLUSION

Relocation of HMGB1 to cytoplasm was confirmed in ccRCC. Methylation of HMGB1 at lysine 112 might the redistribution of this cofactor protein.

Comparison of sorafenib-loaded poly (lactic/glycolic) acid and DPPC liposome nanoparticles in the in vitro treatment of renal cell carcinoma

The objective of this study is to develop and compare several Sorafenib-loaded biocompatible nanoparticle models in order to optimize drug delivery and tumor cellular kill thereby improving the quality of Sorafenib-regimented chemotherapy. Sorafenib-loaded poly (lactic-co-glycolic) acid (PLGA), 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) liposomes, and hydrophobically modified chitosan (HMC)-coated DPPC liposomes were evaluated for several characteristics including zeta potential, drug loading, and release profile. Cytotoxicity and uptake trials were also studied using cell line RCC 786-0, a human metastatic clear cell histology renal cell carcinoma cell line. Sorafenib-loaded PLGA particles and HMC-coated DPPC liposomes exhibited significantly improved cell kill compared to Sorafenib alone at lower concentrations, namely 10-15 and 5-15 μM from 24 to 96 h, respectively. At maximum dosage and time (15 μM and 96 h), Sorafenib-loaded PLGA and HMC-coated liposomes killed 88.3 ± 1.8% and 98 ± 1.1% of all tumor cells, significant values compared with Sorafenib 81.8 ± 1.7% (p < 0.01). Likewise, HMC coating substantially improved cell kill for liposome model for all concentrations (5-15 μM) and at time points (24-96 h) (p < 0.01). PLGA and HMC-coated liposomes are promising platforms for drug delivery of Sorafenib. Because of different particle characteristics of PLGA and liposomes, each model can be further developed for unique clinical modalities.

Umbelliferone β-d-galactopyranoside inhibits chemically induced renal carcinogenesis via alteration of oxidative stress, hyperproliferation and inflammation: possible role of NF-κB

Umbelliferone (7-hydroxycoumarin) compound possesses strong anti-inflammatory and free radical scavenging activity.

A multigene assay identifying distinct prognostic subtypes of clear cell renal cell carcinoma with differential response to tyrosine kinase inhibition

Patients with clear cell renal cell carcinoma (ccRCC) have divergent survival outcomes and therapeutic responses, which may be determined by underlying molecular diversity. We aimed to develop a practical molecular assay that can identify subtypes with differential prognosis and response to targeted therapy. Whole-genome expression analysis of formalin-fixed paraffin-embedded (FFPE) material from 55 ccRCC patients was performed and two molecular subtypes with differential clinical outcomes were identified by hierarchical clustering. An eight-gene quantitative polymerase chain reaction assay for classification into two subtypes was developed for FFPE material. The primary objective was to assess assay performance by correlating ccRCC prognostic subtypes to cancer-specific survival (CSS) and, for patients receiving targeted therapy, radiologic response. In three validation cohorts, patients could be distinguished into prognostic subtypes with differential CSS (Singapore General Hospital FFPE cohort: n = 224; p = 1.48 × 10(-8); the Cancer Genome Atlas RNA-Sequencing cohort: n = 419; p = 3.06 × 10(-7); Van Andel Research Institute microarray cohort: n=174; p=0.00743). For 48 patients receiving tyrosine kinase inhibitor (TKI) treatment, the prognostic classification was associated with radiologic response to treatment (p = 5.96 × 10(-4)) and prolonged survival on TKI treatment (p=0.019). The multigene assay can classify ccRCCs into clinical prognostic subtypes, which may be predictive of response in patients receiving TKI therapy.

Metastatic renal cell carcinoma to the testis: A case report and review of the literature

This is a case of a 68-year-old male who presented with a chief compliant of a testicular mass, which was discovered to be a meta-static lesion of undiagnosed renal cell carcinoma. A computed tomography scan revealed a large right renal mass and multiple pulmonary metastasis. Shortly after diagnosis, the patient was initiated on systemic therapy and received a cytoreductive nephrectomy. We discuss the details of this case as well as a pertinent review of metastatic renal cell carcinoma to the testes.

Comparing two tyrosine kinase inhibitors for treatment of advanced renal cell carcinoma in Medicare and commercially insured patients

OBJECTIVE

The objective of this study was to compare treatment characteristics, survival and costs for sunitinib and pazopanib for advanced renal cell carcinoma (RCC) in a real-world setting.

METHODS

Using claims data, this observational, retrospective cohort study selected individuals aged 19 to 89 years, with commercial or Medicare insurance, advanced RCC, and at least one pharmacy claim for sunitinib or pazopanib between 1 November 2009 and 31 December 2012. Treatment characteristics (treatment interruption, adherence, duration and discontinuation), survival, and costs were measured up to 12 months. Statistical models were adjusted for age, gender, geographic region, race, and RxRisk-V score.

RESULTS

At baseline, pazopanib patients exhibited significantly worse health status indicators (RxRisk-V score, number of pharmacy claims, and pre-index total healthcare costs) than sunitinib patients. There were no differences in treatment characteristics or survival. Index medication costs (mean difference $5580, p = 0.03, adj p = 0.05) and total healthcare costs (mean difference $12,192, p = 0.09, adj p = 0.07) trended higher with sunitinib. Patients non-adherent with sunitinib incurred significantly higher total costs compared to patients non-adherent with pazopanib (mean difference $17,680, p = 0.04, adj p = 0.01).

CONCLUSIONS

Mortality data and proxy variables for treatment effectiveness indicate comparable clinical value for both medications. Sunitinib treatment trended towards higher index medication and total healthcare costs despite higher pre-index total costs and worse health status indicators at baseline with pazopanib. Non-adherence with sunitinib was associated with significantly higher total healthcare costs, which may indicate differences in tolerability between the two agents and requires further investigation.

RNA interference-mediated knockdown of astrocyte elevated gene-1 inhibits growth, induces apoptosis, and increases the chemosensitivity to 5-fluorouracil in renal cancer Caki-1 cells

Astrocyte elevated gene-1 (AEG-1) is a recently discovered oncogene that has been reported to be highly expressed in various types of malignant tumors, including renal cell carcinoma. However, the precise role of AEG-1 in renal cancer cell proliferation and apoptosis has not been clarified. In this study, we transfected the renal cancer cell line Caki-1 with a plasmid expressing AEG-1 short hairpin RNA (shRNA) and obtained cell colonies with stable knockdown of AEG-1. We found that AEG-1 down-regulation inhibited cell proliferation and colony formation and arrested cell cycle progression at the sub-G1 and G0/G1 phase. Western blot analysis indicated that the expression of proliferating cell nuclear antigen (PCNA), cyclin D1 and cyclin E were significantly reduced following AEG-1 down-regulation. In addition, AEG-1 knockdown led to the appearance of apoptotic bodies in renal cancer cells, and the ratio of apoptotic cells significantly increased. Expression of the anti-apoptotic factor Bcl-2 was dramatically reduced, whereas the pro-apoptotic factors Bax, caspase-3 and poly (ADP-ribose) polymerase (PARP) were significantly activated. Finally, AEG-1 knockdown in Caki-1 cells remarkably suppressed cell proliferation and enhanced cell apoptosis in response to 5-fluorouracil (5-FU) treatment, suggesting that AEG-1 inhibition sensitizes Caki-1 cells to 5-FU. Taken together, our data suggest that AEG-1 plays an important role in renal cancer formation and development and may be a potential target for future gene therapy for renal cell carcinoma.

Expression of Ror2 mediates invasive phenotypes in renal cell carcinoma

Ror2 is a Wnt ligand receptor that is overexpressed in a variety of tumors including clear cell renal cell carcinoma (ccRCC). Here we demonstrate that expression of wild type Ror2 results in increased tumorigenic properties in in vitro cell culture and in vivo xenograft models. In addition, Ror2 expression produced positive changes in both cell migration and invasion, which were dependent on matrix metalloprotease 2 (MMP2) activity. Mutations in key regions of the kinase domain of Ror2 resulted in the abrogation of increased tumor growth, cell migration, and cell invasion observed with expression of wild-type Ror2. Finally, we examined Ror2 expression as a prognostic biomarker for ccRCC utilizing the TCGA ccRCC dataset. High expression of Ror2 showed a significant correlation with higher clinical stage, nuclear grade, and tumor stage. Furthermore, high expression of Ror2 in ccRCC patients correlated with significant lower overall survival, cancer specific survival, and recurrence free survival. Together, these findings suggest that Ror2 plays a central role in influencing the ccRCC phenotype, and can be considered as a negative prognostic biomarker and potential therapeutic target in this cancer.

Circulating biomarkers in renal cell carcinoma: the link between microRNAs and extracellular vesicles, where are we now?

Renal cell carcinoma (RCC) is a lethal urological cancer, with incidence and mortality rates increasing by 2-3% per decade. The lack of standard screening tests contributes to the fact that one-third of patients are diagnosed with locally invasive or metastatic disease. Moreover, 20-40% of RCC patients submitted to surgical nephrectomy will develop metastasis. MicroRNAs (miRNAs) are small non-coding RNAs responsible for gene regulation at a post-transcriptional level. It is accepted that they are deregulated in cancer and can influence tumor development. Thus, miRNAs are promising RCC biomarkers, since they can be detected using non-invasive methods. They are highly stable and easier to quantify in circulating biofluids. The elevated miRNA stability in circulating samples may be the consequence of their capacity to circulate inside of extracellular microvesicles (EMVs), for example, the exosomes. The EMVs are bilayered membrane vesicles secreted by all cell types. They can be released in the interstitial space or into circulating biofluids, which allows the travelling, binding and entrance of these vesicles in receptor cells. This type of cell communication can shuttle bioactive molecules between cells, allowing the horizontal transference of genetic material. In this review, we focus on circulating miRNAs (miR-210, miR-1233, miR-221, miR-15a, miR-451, miR-508, miR-378) in the biofluids of RCC patients and attempt to establish the diagnostic and prognostic accuracy, their synergic effects, and the pathways involved in RCC biology.

Comparative Effectiveness of Second-Line Targeted Therapies for Metastatic Renal Cell Carcinoma: A Systematic Review and Meta-Analysis of Real-World Observational Studies

OBJECTIVE

The optimal sequencing of targeted therapies for metastatic renal cell carcinoma (mRCC) is unknown. Observational studies with a variety of designs have reported differing results. The objective of this study is to systematically summarize and interpret the published real-world evidence comparing sequential treatment for mRCC.

METHODS

A search was conducted in Medline and Embase (2009-2013), and conference proceedings from American Society of Clinical Oncology (ASCO), ASCO Genitourinary Cancers Symposium (ASCO-GU), and European Society for Medical Oncology (ESMO) (2011-2013). We systematically reviewed observational studies comparing second-line mRCC treatment with mammalian target of rapamycin inhibitors (mTORi) versus vascular endothelial growth factor (VEGF) tyrosine kinase inhibitors (TKI). Studies were evaluated for 1) use of a retrospective cohort design after initiation of second-line therapy, 2) adjustment for patient characteristics, and 3) use of data from multiple centers. Meta-analyses were conducted for comparisons of overall survival (OS) and progression-free survival (PFS).

RESULTS

Ten studies reported OS and exhibited significant heterogeneity in estimated second-line treatment effects (I2 = 68%; P = 0.001). Four of these were adjusted, multicenter, retrospective cohort studies, and these showed no evidence of heterogeneity (I2 = 0%; P = 0.61) and a significant association between second-line mTORi (>75% everolimus) and longer OS compared to VEGF TKI (>60% sorafenib) (HR = 0.82, 95% CI: 0.68 to 0.98) in a meta-analysis. Seven studies comparing PFS showed significant heterogeneity overall and among the adjusted, multicenter, retrospective cohort studies. Real-world observational data for axitinib outcomes was limited at the time of this study.

CONCLUSIONS

Real-world studies employed different designs and reported heterogeneous results comparing the effectiveness of second-line mTORi and VEGF TKI in the treatment of mRCC. Within the subset of adjusted, multicenter observational studies, second-line use of mTORi was associated with significantly prolonged survival compared with second-line use of VEGF TKI.

Recent advances in the use of therapeutic cancer vaccines in genitourinary malignancies

INTRODUCTION

Despite a recent increase in US FDA-approved treatments, genitourinary malignancies remain a source of significant morbidity and mortality. One focus of research is the use of therapeutic cancer vaccines in these diseases, and a significant body of clinical trial experience now exists for refining vaccine strategies to enhance antitumor efficacy and develop immune-based combination regimens.

AREAS COVERED

In recent years, clinical data from multiple trials in genitourinary malignancies have enhanced our understanding of the potential for immunotherapy in these cancers. There are also emerging clinical strategies that combine cancer vaccines with chemotherapy, radiation, androgen-deprivation therapy and immune checkpoint inhibitors. This review is based on a search of relevant literature for data presented over the past 5 years from clinical trials of cancer vaccines in prostate, bladder and renal carcinomas.

EXPERT OPINION

In the coming years, clinical trials informed by decades of preclinical data and emerging clinical data will help to define the role of immunotherapy in genitourinary malignancies. Combination strategies that capitalize on the immune properties of standard treatments will bring greater clinical benefits, and immune-based combinations will likely be moved to the neoadjuvant setting, where they may have optimal clinical impact.

ITPR1 protects renal cancer cells against natural killer cells by inducing autophagy

Clear cell renal cell carcinomas (RCC) frequently display inactivation of von Hippel-Lindau (VHL) gene leading to increased level of hypoxia-inducible factors (HIF). In this study, we investigated the potential role of HIF2α in regulating RCC susceptibility to natural killer (NK) cell-mediated killing. We demonstrated that the RCC cell line 786-0 with mutated VHL was resistant to NK-mediated lysis as compared with the VHL-corrected cell line (WT7). This resistance was found to require HIF2α stabilization. On the basis of global gene expression profiling and chromatin immunoprecipitation assay, we found ITPR1 (inositol 1,4,5-trisphosphate receptor, type 1) as a direct novel target of HIF2α and that targeting ITPR1 significantly increased susceptibility of 786-0 cells to NK-mediated lysis. Mechanistically, HIF2α in 786-0 cells lead to overexpression of ITPR1, which subsequently regulated the NK-mediated killing through the activation of autophagy in target cells by NK-derived signal. Interestingly, both ITPR1 and Beclin-1 silencing in 786-0 cells inhibited NK-induced autophagy and subsequently increased granzyme B activity in target cells. Finally, in vivo ITPR1 targeting significantly enhanced the NK-mediated tumor regression. Our data provide insight into the link between HIF2α, the ITPR1-related pathway, and natural immunity and strongly suggest a role for the HIF2α/ITPR1 axis in regulating RCC cell survival.

Are urologists and radiologists equally effective in determining the RENAL Nephrometry score?

BACKGROUND

The RENAL nephrometry score (RNS) allows description of the anatomy and the complexity of renal masses. This study aimed to investigate the interobserver reproducibility of the RNS between a radiologist and a urologist.

METHODS

The computed tomography (CT) scans of patients undergoing partial nephrectomy in the authors' department between June 2010 and June 2013 were analyzed for determination of the RNS by a urologist and a radiologist blinded to the medical records. Cohen's kappa coefficient was used for interobserver reproducibility assessment. Correlations with per- and postoperative complication rates and renal function were assessed.

RESULTS

The study included 52 consecutive patients with a mean age of 55 years. The average score was 7.4 ± 1.7 for the urologist and 7.3 ± 1.5 for the radiologist. The Cohen's kappa was 0.81 for R, 0.47 for E, 0.63 for N, 0.28 for A, and 0.21 for L. The Pearson's coefficient for the total RNS was 0.70. The operative time and the occurrence of major complications were significantly correlated with the complexity assessed by the score of both observers. In the univariate analysis, the RNS, the American Society of Anesthesiologists score, and the patient's age were significantly associated with major complication rates. In the multivariate analysis, the RNS remained significantly associated with major complications. No significant difference in postoperative renal function according to complexity group was found by either the urologist or the radiologist.

CONCLUSIONS

The reproducibility of the RNS between the radiologist and the urologist was not very good, especially for some items referring to the location of the tumor, although the major complication rates were significantly associated with the RNS for both observers.

Identification of potential serum proteomic biomarkers for clear cell renal cell carcinoma

Objective

To investigate discriminating protein patterns and serum biomarkers between clear cell renal cell carcinoma (ccRCC) patients and healthy controls, as well as between paired pre- and post-operative ccRCC patients.

Methods

We used magnetic bead-based separation followed by matrix-assisted laser desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) to identify patients with ccRCC. A total of 162 serum samples were analyzed in this study, among which there were 58 serum samples from ccRCC patients, 40 from additional paired pre- and post-operative ccRCC patients (n = 20), and 64 from healthy volunteers as healthy controls. ClinProTools software identified several distinct markers between ccRCC patients and healthy controls, as well as between pre- and post-operative patients.

Results

Patients with ccRCC could be identified with a mean sensitivity of 88.38% and a mean specificity of 91.67%. Of 67 m/z peaks that differed among the ccRCC, healthy controls, pre- and post-operative ccRCC patients, 24 were significantly different (P<0.05). Three candidate peaks, which were upregulated in ccRCC group and showed a tendency to return to healthy control values after surgery, were identified as peptide regions of RNA-binding protein 6 (RBP6), tubulin beta chain (TUBB), and zinc finger protein 3 (ZFP3) with the m/z values of 1466.98, 1618.22, and 5905.23, respectively.

Conclusion

MB-MALDI-TOF-MS method could generate serum peptidome profiles of ccRCC, and provide a new approach to identify potential biomarkers for diagnosis as well as prognosis of this malignancy.

Clinical outcome of advanced and metastatic renal cell carcinoma treated with targeted therapy: is there a difference between young and old patients?

Background

To assess whether the clinical outcome of advanced and metastatic renal cell carcinoma (mRCC) treated with targeted therapy differs between young and old patients.

Patients and methods

A total of 327 patients with advanced renal cell carcinoma and mRCC who received targeted therapy in two Chinese clinical centers were analyzed retrospectively. The patients were stratified into three groups: young (aged <45 years), middle-aged (aged 45–64 years), and old (aged ≥65 years). Overall survival (OS) and progression-free survival (PFS) curves were drawn using the Kaplan–Meier method, and Cox’s proportional hazard regression model was used to compare OS and PFS within age groups.

Results

There were no significant differences among young, middle-aged, and old groups in terms of OS (P=0.087), whereas PFS in the old group was significantly better than in the young and middle-aged groups (P=0.043). Both OS and PFS in the younger groups (aged <65 years) were significantly worse than in the old group (age ≥65 years; median OS, 28.1 vs 28.7 months [P=0.029]; median PFS, 11.4 vs 14 months [P=0.015]). No difference in OS or PFS was found between the young and middle-aged groups. After adjusting for sex, body mass index, smoking status, hypertension, diabetes mellitus, Eastern Cooperative Oncology Group score, history of cytokines, and Fuhrman grade, old age was an independent favorable prognostic factor for OS and PFS compared with younger age (<65 years) (OS, hazard ratio, 0.552 [95% confidence interval, 0.329–0.828; P=0.006]; PFS, hazard ratio, 0.584 [95% confidence interval, 0.401–0.850; P=0.005]).

Conclusion

Younger patients with advanced renal cell carcinoma and mRCC receiving targeted therapy have a poorer prognosis compared with old patients. These results remain to be examined in prospective cohorts.

Costs associated with adverse events in patients with metastatic renal cell carcinoma

OBJECTIVE

To estimate adverse event (AE) costs in patients receiving targeted therapies for the first line treatment of metastatic renal cell carcinoma (mRCC).

METHODS

Retrospective study based on healthcare claims data for patients with mRCC, aged ≥18 years, receiving first-line treatment with targeted therapies. AEs of interest comprised of abdominal pain, back pain, diarrhea, dyspnea, extremity pain, fatigue/asthenia, hand-foot syndrome, hypertension, lymphopenia, nausea/vomiting, neutropenia, proteinuria, and thrombocytopenia. Healthcare encounters for AEs were based on ICD-9-CM diagnosis/procedure codes on healthcare claims. AE costs were examined over a 30-day period, beginning with the date of first mention of AE, and were estimated based on the difference in total costs between patients with and without events. Drug costs of targeted agents were excluded from the analysis. Multivariate generalized linear models with a log-link function and gamma response probability distribution were utilized to control for differences in baseline characteristics between patients with and without evidence of AEs.

RESULTS

A total of 533 patients were included in this analysis: 418 patients with AE and 115 patients without AE. Baseline characteristics were generally similar between patients in the two groups. The GLM-based estimate of incremental 30-day post-event costs among patients with evidence of any adverse events was $9807 (95% CI = $4386-$22,947). For all types of adverse events examined, the estimated difference in costs between evented and non-evented patients was positive; the 95% CI did not include zero for all of the adverse events considered, except hypertension and proteinurea. Study limitations include errors of commission/omission, especially as they may affect case-finding methods that rely on ICD-9-CM diagnosis and procedure codes, as was the case in the current study.

CONCLUSION

Costs associated with AEs of first-line targeted therapies are substantial in patients with mRCC. Efforts to prevent and/or better manage these events may reduce overall healthcare costs.

Label-free quantitative proteomic analysis reveals potential biomarkers and pathways in renal cell carcinoma

Renal cell carcinoma (RCC) is one of the most common malignancies in adults, and there is still no acknowledged biomarker for its diagnosis, prognosis, recurrence monitoring, and treatment stratification. Besides, little is known about the post-translational modification (PTM) of proteins in RCC. Here, we performed quantitative proteomic analysis on 12 matched pairs of clear cell RCC (ccRCC) and adjacent kidney tissues using liquid chromatography-tandem mass spectrometry (nanoLCMS/MS) and Progenesis LC-MS software (label-free) to identify and quantify the dysregulated proteins. A total of 1872 and 1927 proteins were identified in ccRCC and adjacent kidney tissues, respectively. Among these proteins, 1037 proteins were quantified by Progenesis LC-MS, and 213 proteins were identified as dysregulated proteins between ccRCC and adjacent tissues. Pathway analysis using IPA, STRING, and David tools was performed, which demonstrated the enrichment of cancer-related signaling pathways and biological processes such as mitochondrial dysfunction, metabolic pathway, cell death, and acetylation. Dysregulation of two mitochondrial proteins, acetyl-CoA acetyltransferase 1 (ACAT1) and manganese superoxide dismutase (MnSOD) were selected and confirmed by Western blotting and immunohistochemistry assays using another 6 pairs of ccRCC and adjacent tissues. Further mass spectrometry analysis indicated that both ACAT1 and MnSOD had characterized acetylation at lysine residues, which is the first time to identify acetylation of ACAT1 and MnSOD in ccRCC. Collectively, these data revealed a number of dysregulated proteins and signaling pathways by label-free quantitative proteomic approach in RCC, which shed light on potential diagnostic or prognostic biomarkers and therapeutic molecular targets for clinical intervention of RCC.

Annexin A2 in renal cell carcinoma: expression, function, and prognostic significance

OBJECTIVE

Renal cell carcinoma (RCC) is the most lethal genitourinary cancer and intrinsically resistant to chemotherapy, radiotherapy, and hormone therapy. Annexin A2 (Anxa2) is a calcium-dependent phospholipid-binding protein found on various cell types that plays multiple roles in regulating cellular functions. In RCC, Anxa2 expression was correlated with tumor differentiation, clinical outcomes, and the metastatic potential; however, the underlying mechanisms remain obscure. This study investigated the role of Anxa2 in regulating tumorigenesis of RCC.

MATERIALS AND METHODS

Commercial RCC tissue microarray arrays and a kidney cancer quantitative polymerase chain reaction array were used to examine Anxa2 by immunohistochemistry and real-time polymerase chain reaction analysis. Short hairpin (sh)RNA-based lentiviral system technology was used to evaluate the effects of manipulating Anxa2 expression on multiple malignant features of 2 RCC cell lines, A498 and 786-O, and its mechanisms.

RESULTS

(1) The Anxa2 expression level was generally elevated to varying degrees in RCC tissues. In adjacent noncancerous tissues, Anxa2 was mainly expressed in glomeruli and slightly expressed in the cytoplasm of proximal tubules. (2) An increased Anxa2 expression level was found in tissues of clear cell RCC, papillary RCC, and chromophobe RCC, and it was prominently expressed in cancer cell membranes. In addition, the Anxa2 expression level was correlated with poor prognosis. (3) Silencing Anxa2 expression suppressed the abilities of cell migration and invasion, but cell proliferation was less affected. (4) Diminished Anxa2 expression caused alterations in the cell polarity, disrupted the formation of actin filaments, and reduced CXCR4 expression. (5) Inhibition of the Rho/Rock axis restored silencing of Anxa2-mediated suppression of cell motility.

CONCLUSIONS

Overall, our study points out the regulatory function of Anxa2 in RCC cell motility and provides a molecular-based mechanism of Anxa2 positivity in the progression of RCC.

A systematic review of the role of hepatectomy in the management of metastatic renal cell carcinoma

AIM

This review sought to systematically appraise the literature to establish the role of hepatectomy in treating renal cell carcinoma hepatic metastases.

METHOD

Medline and EMBASE were systematically searched for papers reporting survival of patients who underwent hepatectomy for metastatic renal cell carcinoma.

RESULTS

Six studies containing 140 patients were included. There were no randomised controlled trials. Perioperative mortality was 4.3%, with reported morbidity between 13 and 30%. Patients with metachronous presentation, and a greater time interval between resection of primary tumour and development of metachronous metastases, appeared to have better survival. There was no difference in survival between patients with solitary and multiple metastases.

CONCLUSION

Few patients with hepatic metastases from renal cell carcinoma are suitable for hepatectomy as metastatic disease is usually widespread. Selected patients may experience a survival benefit, but identifying these patients remains difficult.

TNF receptors: signaling pathways and contribution to renal dysfunction

Tumor necrosis factor (TNF), initially reported to induce tumor cell apoptosis and cachexia, is now considered a central mediator of a broad range of biological activities from cell proliferation, cell death and differentiation to induction of inflammation and immune modulation. TNF exerts its biological responses via interaction with two cell surface receptors: TNFR1 and TNFR2. (TNFRs). These receptors trigger shared and distinct signaling pathways upon TNF binding, which in turn result in cellular outputs that may promote tissue injury on one hand but may also induce protective, beneficial responses. Yet the role of TNF and its receptors specifically in renal disease is still not well understood. This review describes the expression of the TNFRs, the signaling pathways induced by them and the biological responses of TNF and its receptors in various animal models of renal diseases, and discusses the current outcomes from use of TNF biologics and TNF biomarkers in renal disorders.

The incidence of renal cancer in Polish National Cancer Registry: is there any epidemiological data we can rely on?

Introduction

The Polish National Cancer Registry (KRN) is the most commonly used sources of data on the incidence of cancers including renal cancer in Poland. Until today, the accuracy and completeness of these data has never been verified.

Material and methods

The aim of this study was to assess the completeness and reliability of data on the incidence of renal cancer published by the KRN. KRN data on newly diagnosed cases of renal cancer in Poland (for the whole country) and separately in subjectively selected provinces between 2009 and 2011 were retrospectively compared to the data received from the National Health Fund (NFZ) on the number of radical and partial nephrectomies performed due to renal cancer in the same time frame and regions.

Results

The concordance between the analysed two sources of data was 86%. Calculated ratio of the number of cases in the KRN database to number of cases in the NFZ database in selected provinces were as follows: 109% in Lubuskie, 60% in Mazowieckie, 123% in Podkarpackie and 66% in Podlaskie. No significant differences were observed between analyzed years (89% in 2009, 88% in 2010, 82% in 2011). The number of unreported cases of renal cancer in KRN was lower among male patients comparing to female patients (concordance: 78% vs. 72%).

Conclusions

The incidence of renal cancer published by KRN is underestimated, thus KRN does not seem to be a fully reliable source of epidemiological data. Due to the fact that this data is crucial for the planning of the health policy in Poland, improving urooncological reporting should be a priority for the health system managers.

The role of metastasectomy in renal cell carcinoma

Despite significant advances in the systemic treatment of metastatic renal cell carcinoma, long-term survival remains low. A potential way to improve outcomes in selected cases is the use of metastasectomy, which is part of the multimodal treatment of this disease. Although the evidence supporting this approach is limited, we believe it is a reasonable option for certain patients. This review summarizes the evidence supporting this approach.

Landmarks in the diagnosis and treatment of renal cell carcinoma

The most common renal cancer is renal cell carcinoma (RCC), which arises from the renal parenchyma. The global incidence of RCC has increased over the past two decades by 2% per year. RCC is the most lethal of the common urological cancers: despite diagnostic advances, 20-30% of patients present with metastatic disease. A clearer understanding of the genetic basis of RCC has led to immune-based and targeted treatments for this chemoresistant cancer. Despite promising results in advanced disease, overall response rates and durable complete responses are rare. Surgery remains the main treatment modality, especially for organ-confined disease, with a selective role in advanced and metastatic disease. Smaller tumours are increasingly managed with biopsy, minimally invasive interventions and surveillance. The future promises multimodal, integrated and personalized care, with further understanding of the disease leading to new treatment options.

MicroRNAs as potential diagnostic biomarkers in renal cell carcinoma

Emerging evidence has suggested that microRNAs (miRNAs) may be promising novel biomarkers for the diagnosis of renal cell carcinoma (RCC). However, the results of current studies are still conflicting. Hence, we undertake the current meta-analysis to comprehensively assess the diagnostic potential of miRNAs in RCC. The bivariate meta-analysis model was employed to summarize the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR). Summary receiver operating characteristic (SROC) curve and area under the curve (AUC) were used to evaluate the diagnostic accuracy. Subgroup analyses and meta-regression were used to explore the between-study heterogeneity. Deeks' funnel plot asymmetry test was used to test the potential of publication bias. All analyses were performed using STATA software (version 12.0). The pooled sensitivity and specificity of miRNAs for the diagnosis of RCC were 0.85 (95% confidence interval (CI), 0.77-0.90) and 0.84 (95% CI, 0.70-0.92). The value of AUC was 0.91 (95% CI, 0.88-0.93), suggesting that the diagnostic accuracy of miRNAs achieved a relatively high level. Furthermore, subgroup analyses showed that tissue-based miRNA assay is recommended to improve the diagnostic accuracy. In conclusion, the high degree of diagnostic accuracy suggests that miRNA in RCC patients may serve as next-generation biomarkers for detection of the disease. However, large-scale investigations and additional improvements are urgently needed to confirm our results and verify the feasibility of routine clinical utilization.

NY-ESO-1 as a potential immunotherapeutic target in renal cell carcinoma

Background: Novel immune therapies targeting tumor specific antigens are being developed. Our purpose was to determine expression of the cancer testes antigen NY-ESO-1 in renal cell carcinoma (RCC), as NY-ESO-1 targeting approaches, particularly adoptive cell therapy, have not been evaluated in this disease.

Methods: We employed tissue microarrays containing >300 unique RCC cases and adjacent benign renal tissue to determine NY-ESO-1 expression using a quantitative immunofluorescence method. In addition, we studied NY-ESO-1 expression in 35 matched primary and metastatic RCC specimens to assess concordance between different tumor sites.

Results: NY-ESO-1 was highly expressed in a subset of RCCs. Expression in primary RCC specimens was significantly higher than adjacent normal renal tissue (P<0.0001) and higher in clear cell carcinomas than papillary RCC (P<0.0001). Expression levels in metastatic specimens were higher than in matched primary samples (P=0.0018), and the correlation between the two sites was modest (χ²=3.5, p=0.06).

Conclusions: Aberrant NY-ESO-1 expression seen in clear cell RCC suggests that NY-ESO-1 targeting approaches should be studied in this disease. Expression is higher in metastatic sites, and discordance between primary and metastatic sites in some patients suggests that patient selection for these therapies should be based on expression in metastatic rather than nephrectomy specimens.

Hydrogen sulfide treatment ameliorates long-term renal dysfunction resulting from prolonged warm renal ischemia-reperfusion injury

INTRODUCTION

The incidence of renal cell carcinoma (RCC) continues to rise concurrently with the increased prevalence of end-stage renal disease worldwide. Treatment for small renal masses continues to be partial nephrectomy mostly involving the clamping of renal blood vessels. Although necessary, this technique results in warm renal ischemia and reperfusion injury (IRI) to the afflicted kidney. We have recently demonstrated that hydrogen sulfide (H2S), a novel endogenous gaseous molecule, protects against prolonged cold and short-term warm renal IRI. In the current study, we examined whether exogenous H2S has long-term protective effects against warm renal IRI associated with renal surgical procedures.

METHODS

Uni-nephrectomized Lewis rats underwent 1 hour of warm ischemia induced by clamping of the renal pelvis. Animals underwent either intraperitoneal treatment with phosphate buffered saline (PBS; IRI group) or PBS supplemented with 150 μM NaHS (H2S group), and were compared against Sham-operated rats.

RESULTS

H2S treatment improved long-term renal function as serum creatinine at day 7 was significantly decreased in the H2S group compared to IRI animals (p < 0.05). H2S treatment decreased the expression of pro-inflammatory markers TLR-4, TNF-α, IFNγ, IL-2 and ICAM-1, increased the expression of pro-survival molecule Bcl-2 and decreased the expression of pro-apoptotic marker BID at postoperative day 1. H2S-treated kidneys also showed a significant decrease (p < 0.05) in infiltration of macrophages at day 7 post-IRI compared to no treatment.

CONCLUSION

H2S treatment improved long-term renal function and decreased long-term inflammation associated with warm IRI, and may offer a novel therapeutic approach to preventing warm IRI-induced renal injury associated with renal surgical procedures.

Emerging antiangiogenics for renal cancer

INTRODUCTION

Antiangiogenic therapy is considered to be the backbone of treatment strategy in metastatic renal cell carcinoma (mRCC). New, more focused, targeted drugs are emerging, while other targeted drugs oriented toward resistance or alternative mechanisms are under development.

AREAS COVERED

Antiangiogenic agents include two types of agents: the monoclonal antibody, targeting vascular endothelial growth factor (VEGF), bevacizumab and the tyrosine kinase inhibitors (TKIs). Data regarding efficacy and safety of these agents are reported. Differences between the first generation of TKIs, sunitinib, sorafenib, and the new generation, pazopanib, axitinib and tivozanib are also detailed. Most of these agents have been approved in the treatment of kidney cancer in specific settings of the disease.

EXPERT OPINION

The class of antiangiogenic drugs for treatment of mRCC is already relatively full. After 'me-too' drugs, more targeted drugs against VEGFR have been developed but have to demonstrate a benefit in first-line treatment. Another option for the development is to combine a known drug with an antiangiogenic inhibition profile and at least one additional target involved in resistance to an antiangiogenic or in an alternative pathway. The cost of approach with targeted drugs, including antiangiogenics, has led to a tremendous increase in the cost of care in mRCC.

Downregulated miR-646 in clear cell renal carcinoma correlated with tumour metastasis by targeting the nin one binding protein (NOB1)

Background:

Nin one binding protein (NOB1) was identified as a potential oncogene in human glioma and miR-646 plays an important role in human growth and development. However, the underlying molecular mechanisms of NOB1 in tumorigenicity and its correlation with miR-646 in renal cell carcinoma (RCC) have not been investigated.

Methods:

We performed bioinformatic analysis to explore miRNA targeting NOB1. The expression of NOB1 and miR-646 from 100 cases of clear cell RCC (ccRCC) and 30 cases of adjacent non-tumour tissues were detected by quantitative real-time PCR. The expression of miR-646 was correlated with NOB1 expression, tumour features and patient metastasis-free survival. The effect of overexpression of mir-646 on renal cancer cell proliferation was detected by colony formation in soft agar. Using a xenograft tumour model, we observed the in vivo tumorigenesis effect of miR-646 and NOB1.

Results:

miR-646 negatively regulated NOB1 and inhibited the proliferation and migration of renal cancer cells. There was a significant upregulation of NOB1 in ccRCC and it was further increased in metastatic cases, while miR-646 was downregulated in tumour tissues and further decreased in metastatic ccRCC. Additionally, expression of miR-646 was inversely correlated with the expression of NOB1. The downregulation of miR-646 also indicated a higher probability of developing metastasis. Most importantly, miR-646 expression was an independent predictor of ccRCC metastasis by the univariate analysis and binary logistic regression model (both P<0.05). Colony formation in soft agar and xenograft tumour model suggested that miR-646 and NOB1 are required for tumorigenesis in vitro and in vivo. Furthermore, suppression of NOB1 increased the phosphorylation of several proteins in MAPK pathway.

Conclusions:

Downregulated miR-646 in ccRCC was associated with tumour metastasis through MAPK pathway by targeting NOB1. miR-646 and NOB1 may play an important role in the development of ccRCC.

Fatigue in patients with advanced renal cell carcinoma receiving sunitinib on an intermittent versus continuous dosing schedule in a randomized phase II trial

A phase II trial in advanced renal cell carcinoma (RCC) found no benefit in efficacy or safety between patients receiving oral sunitinib 50 mg/day for 4 weeks followed by 2-week off-treatment (Schedule 4/2) and those receiving 37.5 mg continuous daily sunitinib. We hypothesized that fatigue would have a more variable “on-off” effect with the 4/2 schedule. A total of 292 patients completed two fatigue-related items on Days 1 and 29 of each treatment cycle. Mean absolute slopes were compared across treatments. A planned analysis of item “I feel fatigued” demonstrated that the mean absolute slope was greater in Schedule 4/2 compared to continuous dosing (0.042 vs. 0.032, P = 0.003), and analysis based on the change from Day 1 to Day 29 (0.52 vs. 0.21, P = 0.002) and, separately, Day 29 to the next Day 1 (−0.38 vs. −0.05, P < 0.001) showed the changes to be significantly larger in Schedule 4/2 than continuous dosing. “I have a lack of energy” showed a similar pattern graphically, however, the planned analysis was not statistically significant based on the absolute slopes but was when Day 1 to Day 29 and Day 29 to Day 1 changes were analyzed separately. The 4/2 arm was associated with a greater degree of variability in fatigue reflecting a possible “on-off” effect whereby patients receiving the 4/2 schedule reported less fatigue at the beginning of each cycle compared to Day 29. The findings can inform care for individuals with advanced RCC receiving intermittent dosing of sunitinib.

Expression of the tumor suppressive miRNA-23b/27b cluster is a good prognostic marker in clear cell renal cell carcinoma

PURPOSE

We observed abnormal expression of the microRNA-23b/27b (miR-23b/27b) cluster in our previous study of miRNA expression signatures. However, the relationship between aberrant miRNA expression and clear cell renal cell carcinoma is not well established. We investigated the functional significance of the miR-23b/27b cluster in clear cell renal cell carcinoma cells and evaluated these miRNAs as biomarkers to predict the risk of clear cell renal cell carcinoma.

MATERIALS AND METHODS

Expression levels of miR-23b and miR-27b were determined by quantitative real-time reverse transcriptase-polymerase chain reaction. The association between miRNA expression and overall survival was estimated by the Kaplan-Meier method. Gain of function assays were performed using mature miR-23b and miR-27b in the 786-O and A498 renal cell carcinoma cell lines. Targets regulated by these miRNAs were predicted by in silico analysis.

RESULTS

Expression of the miR-23b/27b cluster was significantly decreased in clear cell renal cell carcinoma tissue specimens and associated with pathological grade and stage. Significantly shorter overall survival was observed in patients with lower expression of the miR-23b/27b cluster. Restoration of miR-23b and miR-27b significantly inhibited cancer cell proliferation, migration and invasion.

CONCLUSIONS

Expression of the miR-23b/27b cluster was frequently decreased in clear cell renal cell carcinoma tissue. Reduced expression of these miRNAs increased the risk of disease progression and predicted poor survival. Thus, miR-23b and miR-27b function as tumor suppressors, targeting several oncogenic genes in clear cell renal cell carcinoma cells.

AIF downregulation and its interaction with STK3 in renal cell carcinoma

Apoptosis-inducing factor (AIF) plays a crucial role in caspase-independent programmed cell death by triggering chromatin condensation and DNA fragmentation. Therefore, it might be involved in cell homeostasis and tumor development. In this study, we report significant AIF downregulation in the majority of renal cell carcinomas (RCC). In a group of RCC specimens, 84% (43 out of 51) had AIF downregulation by immunohistochemistry stain. Additional 10 kidney tumors, including an oxyphilic adenoma, also had significant AIF downregulation by Northern blot analysis. The mechanisms of the AIF downregulation included both AIF deletion and its promoter methylation. Forced expression of AIF in RCC cell lines induced massive apoptosis. Further analysis revealed that AIF interacted with STK3, a known regulator of apoptosis, and enhanced its phosphorylation at Thr180. These results suggest that AIF downregulation is a common event in kidney tumor development. AIF loss may lead to decreased STK3 activity, defective apoptosis and malignant transformation.

Cost-effectiveness analyses of targeted oral anti-cancer drugs: a systematic review

BACKGROUND

Over the last 15 years, a paradigm shift in oncology has led to the approval of dozens of targeted oral anti-cancer medications (OAMs), which have become the standard of care for certain cancers. While more convenient for patients than infused drugs, the possibility of non-adherence and the frequently high costs of targeted OAMs have proven controversial.

OBJECTIVE

Our objective was to perform the first comprehensive review of cost-effectiveness analyses (CEAs) of targeted OAMs.

METHODS

A literature search in PubMed, The Cochrane Library, and the Health Technology Assessment (HTA) reports published by the National Institute for Health Research HTA Programme in the UK was performed, covering articles published in the 5 years prior to 30 September 2013. Our inclusion criteria were peer-reviewed English-language full-text original research articles with a primary focus on CEA related to targeted OAMs. We categorized these articles by treatment setting (i.e. cancer site/type, line of therapy, and treatment and comparator) and synthesized information from the articles into summary tables.

RESULTS

We identified 41 CEAs covering nine of the 18 targeted OAMs approved by the US FDA as of December 2012. These medications were studied in seven cancers, most often as second-line therapy for advanced-stage patients. In over half of treatment settings where a targeted OAM was compared with treatment that was not a targeted OAM, targeted OAMs were considered cost effective. Limitations in interpreting these findings include the risk of bias due to author conflicts of interest, cross-country variation, and difficulties in generalizing clinical trial evidence to community practice.

CONCLUSIONS

Several types of cost-effectiveness studies remain under-represented in the literature on targeted OAMs, including those for follow-on indications approved after the initial indication for a drug and for off-label indications, head-to-head comparisons of targeted OAMs with other targeted OAMs and targeted intravenous therapies, and studies that adopt a perspective other than the payer's. Keeping up with the increasing number of approved targeted OAMs will also prove an important challenge for economic evaluation.

Surgical management of renal cell carcinoma

Surgical resection of renal cell carcinoma (RCC) is the benchmark for long-term cure of the disease. Although open or laparoscopic radical nephrectomy is considered the gold standard for stage T1b-T4 tumors, nephron-sparing surgery is the preferred operative modality for small renal masses demonstrating equivalent oncologic efficacy and improved renal function outcomes compared with complete nephrectomy. With the advance of minimally invasive surgery, nephron-sparing procedures can safely be conducted laparoscopically with or without robotic assistance. RCC with intravenous tumor thrombus presents a surgical challenge, but multidisciplinary surgical approaches can provide long-term benefit in these patients. The role of cytoreductive nephrectomy and metastasectomy in patients with metastatic RCC (mRCC) is controversial, but seems to be beneficial for patients in the era of targeted therapy.