Cancer-specific survival outcomes among patients treated during the cytokine era of kidney cancer (1989-2005): a benchmark for emerging targeted cancer therapies

Applications of metabolomics for kidney disease research: from biomarkers to therapeutic targets

Metabolomics is one of the relative newcomers of the omics techniques and is likely the one most closely related to actual real-time disease pathophysiology. Hence, it has the power to yield not only specific biomarkers but also insight into the pathophysiology of disease. Despite this power, metabolomics as applied to kidney disease is still in its early adolescence and has not yet reached the mature stage of clinical application, i.e., specific biomarker and therapeutic target discovery. On the other hand, the insight gained from hints into what makes these diseases tick, as is evident from the metabolomics pathways which have been found to be altered in kidney cancer, are now beginning to bear fruit in leading to potential therapeutic targets. It is quite likely that, with greater numbers of clinical materials and with more investigators jumping into the field, metabolomics may well change the course of kidney disease research.

High-expression of ZBP-89 correlates with distal metastasis and poor prognosis of patients in clear cell renal cell carcinoma

ZBP-89, a Krüppel-type zinc-finger transcription factor, is found to participate in tumor development, invasion and metastasis. However, the expression status of ZBP-89 in clear cell renal cell carcinoma (CCRCC) remains elusive. Using quantitative real-time-PCR and Western Blot, we found that, in fresh cancer tissues, ZBP-89 was remarkably decreased in 79.2% (19/24) and 83.3% (5/6) of CCRCC at mRNA and protein level, respectively. Immunohistochemistry also revealed a significant decline of ZBP-89 expression in CCRCC, showing that low expression of ZBP-89 was present in 73.9% (105/142) of tumorous tissues but in 48.1% (52/108) of the corresponding adjacent kidney tissues. Furthermore, ZBP-89 expression in CCRCC was significantly correlated with several clinicopathological features, including TNM stage (P=0.005) and distal metastasis (P=0.001). Further study confirmed that ZBP-89 expression was markedly higher in metastatic CCRCC than that in non-metastatic tissue (P=0.002). In addition, CCRCC patients with low ZBP-89 expression survived longer than those with high ZBP-89 expression, as indicated by the result of univariate analysis (P<0.0001). More importantly, multivariate analysis revealed that ZBP-89 was an independent predictor of overall survival (HR, 2.871; 95% CI, 1.409-5.853; P=0.004). Collectively, our study provides vigorous evidence that ZBP-89 was significantly downregulated in CCRCC and could be served as a promising biomarker for prediction of distal metastasis and prognosis of patient with CCRCC.

Predictors of response to targeted therapy in renal cell carcinoma

CONTEXT

The prognosis for patients with metastatic renal cell carcinoma is poor, with an average 5-year survival of approximately 10%. Use of traditional cytokine therapy, specifically high-dose interleukin 2, is limited by significant toxicity. Better understanding of the molecular pathogenesis of renal cell carcinoma has led to the development of targeted therapies to inhibit specific cellular pathways leading to tumorigenesis. These drugs provide improved survival with a more favorable toxicity profile. There is ongoing investigation of markers that predict response of an individual patient to different targeted therapies.

OBJECTIVE

To explain the molecular basis for vascular endothelial growth factor inhibitor (antiangiogenic) and mammalian target of rapamycin inhibitor therapies for renal cell carcinoma, summarize the clinical trials demonstrating the effectiveness of these drugs, and describe the biomarkers shown to correlate with outcome in patients treated with targeted therapy.

DATA SOURCES

All included sources are from peer-reviewed journals in PubMed (US National Library of Medicine).

CONCLUSION

Emerging evidence shows promise that biomarkers will be useful for predicting an individual patient's response to targeted therapy, leading to a more personalized approach to treating renal cell carcinoma.

Prostaglandin E2 regulates renal cell carcinoma invasion through the EP4 receptor-Rap GTPase signal transduction pathway

Prognosis for patients with early stage kidney cancer has improved, but the treatment options for patients with locally advanced disease and metastasis remain few. Understanding the molecular mechanisms that regulate invasion and metastasis is critical for developing successful therapies to treat these patients. Proinflammatory prostaglandin E(2) plays an important role in cancer initiation and progression via activation of cognate EP receptors that belong to the superfamily of G protein-coupled receptors. Here we report that prostaglandin E(2) promotes renal cancer cell invasion through a signal transduction pathway that encompasses EP4 and small GTPase Rap. Inactivation of Rap signaling with Rap1GAP, like inhibition of EP4 signaling with ligand antagonist or knockdown with shRNA, reduces the kidney cancer cell invasion. Human kidney cells evidence increased EP4 and decreased Rap1GAP expression levels in the malignant compared with benign samples. These results support the idea that targeted inhibition of EP4 signaling and restoration of Rap1GAP expression constitute a new strategy to control kidney cancer progression.

Combined immunotherapy with low-dose IL-2 plus IFN-alpha for metastatic renal cell carcinoma: survival benefit for selected patients with lung metastasis and serum sodium level

OBJECTIVE

To clarify the survival benefit of immunotherapy for renal cell carcinoma patients with lung metastasis using low-dose interleukin-2 plus interferon-α, we examined survival outcomes and factors associated with prognosis.

METHODS

This was a multicenter prospective study. Nephrectomized renal cell carcinoma patients with lung metastasis were treated with interleukin-2 (0.7 × 10(6) unit, 5 days a week) and interferon-α (6 × 10(6) IU, 3 days a week) for the first 8 weeks, and then with both interleukin-2 and interferon-α, 2 or 3 days a week for 16 additional weeks.

RESULTS

Median follow-up period for 42 patients was 28.3 months (range: 4.2-43.8). Two-year overall survival rate was 82% and the probability of 3 year survival rate was 71%. Median progression-free survival was 10.4 months. While no difference was found in survival among patients assessed as complete response, partial response and no change, survival of patients assessed as NC or better was significantly better than those assessed as progressive disease (P < 0.0001). Furthermore, multivariate analyses identified pre-treatment serum sodium (P = 0.004) as an independent prognostic factor. The sodium level was also statistically associated with tumor response (p = 0.035). Patients with normal sodium level survived significantly longer (P = 0.0005) than those with low sodium level showing median survival of 12.2 months.

CONCLUSIONS

Combination immunotherapy with low-dose interleukin-2 plus interferon-α showed survival benefit for patients with lung metastasis whose tumor responded as no change or better. This combination immunotherapy could be beneficial for patients selected by metastatic organ and their pre-treatment serum sodium level.

Native renal cysts and dialysis duration are risk factors for renal cell carcinoma in renal transplant recipients

Urinary tract cancers are the third most common cancers in renal transplant recipients (RTX). This study examined the impact of dialysis duration and native renal cyst(s) (NRC) on renal cell carcinoma (RCC) occurrence among 1036 RTX followed-up from 1995 to July 2007. Abdominal ultrasonography was planned within 1-month of transplant, then every 5 years, or 2 years if renal cysts developed. Based on presence and time of development of NRC, RTX were grouped into those with no (No-NRC), new (New-NRC), preexisting (Pre-NRC) and time-indeterminate NRC (TI-NRC). Ten asymptomatic RTX were diagnosed with RCC at a median of 5.8 years posttransplant and had 5-year graft and patient survivals of 90% and 100%, respectively, following appropriate therapy. RCC occurred only in Pre-NRC and TI-NRC who had significantly longer dialysis duration than No- or New-NRC (6.7 ± 3.9 and 3.3 ± 3.2 vs. 2.7 ± 3.1 and 2.6 ± 2.4 years, respectively). These results suggest that NRC and increased dialysis duration are risk factors for RCC posttransplant. Since early treatment of RCC gives excellent outcomes, regular ultrasonography performed within a month of transplantation, then every 5 years for those without cysts and every 2 years for those with cysts for early detection of RCC is recommended.

Breaking through a plateau in renal cell carcinoma therapeutics: development and incorporation of biomarkers

With the Food and Drug Administration approval of 6 novel targeted agents since December 2005 and limited comparative trials to discern relative efficacy, the treatment of metastatic renal cell carcinoma (RCC) has become immensely complex. The research community must look to novel ways in which to identify appropriate candidates for selected targeted therapies; one potential strategy is the use of clinical and molecular biomarkers. A growing body of knowledge-related von Hippel Lindau-driven pathways in this disease has highlighted the potential role of hypoxia-inducible factor subtypes in distinguishing RCC patients clinically. Techniques applied in other malignancies, such as gene expression and proteomic profiling, may also ultimately allow for clinical stratification. An emerging understanding of immunologic phenomena that may affect cancer progression (i.e., tumor infiltration by CD68 lymphocytes, memory T-cells, etc.) has unveiled a number of other potential biomarkers of response. Several vascular endothelial growth factor receptor-directed therapies classically thought to function as antiangiogenics may also have complex effects upon the tumor microenvironment including the associated immune cell milieu. As such, immunologic parameters could potentially predict response to current therapies. Finally, clinical biomarkers, such as hypertension, may predict the efficacy of several currently available targeted agents, although implementation of such biomarkers remains challenging. Herein, the clinical relevance of putative RCC biomarkers is examined in detail.

Fatigue in renal cell carcinoma: the hidden burden of current targeted therapies

Fatigue is one of the most common symptoms associated with cancer. Persistent fatigue can impair multiple aspects of daily functioning and quality of life, and patients report that treatment-related fatigue has a greater impact than other symptoms, including pain, nausea, and depression. Thus, management of fatigue is recognized as an important component of care for patients with cancer. Treatment of advanced and metastatic renal cell carcinoma (RCC) was, until recently, limited to cytokine-based therapies, which are associated with modest response rates and significant toxicity, including high rates of treatment-related fatigue. The paradigm for RCC treatment has shifted dramatically in the last 5 years with the advent of efficacious targeted therapies. These agents provide the promise of better tolerability because of their more selective mechanisms of action. However, there is considerable variation in the selectivity of targeted agents for RCC, and a review of randomized clinical trials in patients with advanced and/or metastatic disease reveals that there is considerable variation in the tolerability of these agents. Fatigue remains a prominent toxicity with current targeted therapies. Future agents that show better selectivity and potency than current targeted therapies should help to provide better efficacy and tolerability.

Identification of a set of genes associated with response to interleukin-2 and interferon-α combination therapy for renal cell carcinoma through genome-wide gene expression profiling

Interleukin (IL)-2 and interferon (IFN)-α combination therapy for metastatic renal cell carcinoma (RCC) improves the prognosis for a subset of patients, while some patients suffer from severe adverse drug reactions with little benefit. To establish a method to predict responses to this combination therapy (approximately 30% response rate), the gene expression profiles of primary RCCs were analyzed using an oligoDNA microarray consisting of 38,500 genes or ESTs, after enrichment of the cancer cell population by laser micro-beam microdissection. The analysis of 10 responders and 18 non-responders identified 24 genes that exhibited significant differential expression between the two groups. In addition, the patients whose tumors did not express HLA-DQA1 or HLA-DQB1 molecules demonstrated poor clinical response. Exclusion of patients with tumors lacking either of these two genes is likely to improve the response rate to IL-2 and IFN-α combination therapy from 30 to 67%, indicating that a simple pretreatment test provides useful information with which to subselect patients with renal cancer in order to improve the efficacy of this treatment and reduce unnecessary medical costs.

Successful outcomes using combination therapy of interleukin-2 and interferon-alpha for renal cell carcinoma patients with lung metastasis

OBJECTIVE

In our previous study, a combination therapy of interleukin-2 and interferon-alpha was found to be more effective than monotherapy, especially for lung metastasis. In order to determine the genetic markers of those who positively responded, a multi-institutional open study was conducted on the patients with lung metastasis. In this paper, the clinical response to our combination therapy is reported.

METHODS

Untreated patients with lung metastasis were enrolled in this study. Patients received interleukin-2 (0.7 x 10(6) U/day) and interferon-alpha (6 x 10(6) IU/day): interleukin-2, 5 days a week and interferon-alpha, 3 days a week for the first 8 weeks, and then both interleukin-2 and interferon-alpha, 2 or 3 days a week for 16 additional weeks.

RESULTS

Forty-two patients were able to be evaluated for response. The overall positive response rate was 35.7% (15 of 42) including 2 patients with complete response. Progression-free patients were observed more frequently in patients with lung metastasis only (80.6%) than those with lung plus other organ metastasis (54.5%). Tumor shrinkage was observed in 81.0% (34 of 42) of patients. Progression-free survival rate at 200 days was 63.6%. Toxicities observed were primarily flu-like symptoms due to the cytokines and were typical of those observed with each single agent.

CONCLUSIONS

Combination therapy of interleukin-2 and interferon-alpha was confirmed to be effective for renal cell carcinoma patients with lung metastasis. Identification of genetic markers is now ongoing with the tissue samples from this trial.

Use of systemic therapy and factors affecting survival for patients undergoing cytoreductive nephrectomy

OBJECTIVE

To present a multi-institutional experience evaluating the use of systemic therapy in patients undergoing cytoreductive nephrectomy (CN), as prospective randomized trials showed a survival benefit for CN in patients with metastatic renal cell carcinoma treated with immunotherapy, and these data have been extrapolated to support CN in the era of targeted therapy, but the likelihood that patients with metastatic kidney cancer who undergo CN will receive systemic treatment afterward remains poorly defined.

PATIENTS AND METHODS

In all, 141 patients who underwent CN between 1990 and 2008 were identified from our Institutional Kidney Cancer Registries. Kaplan-Meier analyses and Cox regression models were used to assess the effect of clinicopathological and perioperative variables on patients' subsequent receipt of systemic therapy, and survival after CN.

RESULTS

Overall, 98 of the 141 patients (69.5%) received postoperative systemic treatment, at a median (range) of 2.5 (0.1-61.5) months after CN. In this group, 52 (53%) patients received immunotherapy, 34 (35%) targeted agents, and 12 (12%) other regimens. By contrast, 43 patients (31%) did not receive systemic therapy, because of rapid disease progression (13, 30%), decision for surveillance by medical oncology (nine, 21%), patient refusal (10, 23%), perioperative death (eight, 19%), and unknown reasons in three (7%). The median (range) survival after CN was 16.7 (0-120) months. The risk of death after surgery correlated with the number of metastatic sites (P = 0.012) and symptoms (P = 0.001) at presentation, poor performance status (P = 0.001), high tumour grade (P = 0.006), and presence of sarcomatoid features (P < 0.024).

CONCLUSION

Nearly a third of patients undergoing CN did not receive systemic treatment. While some were electively observed or declined therapy, others did not receive treatment due to rapidly progressive disease. Further investigation is warranted to identify those patients at highest risk of rapid postoperative disease progression who might benefit instead from an initial approach to treatment with systemic therapy.

Expression and cytoplasmic localization of SAM68 is a significant and independent prognostic marker for renal cell carcinoma

PURPOSE

This retrospective study aimed to examine the expression and localization of SAM68 (Src-associated in mitosis, 68 kDa) in a larger cohort of surgical specimens of renal cell carcinoma and their correlation with the progression of human renal cell carcinoma.

EXPERIMENTAL DESIGN

The protein and mRNA expression levels of SAM68 in normal renal tubular epithelial cells, renal cell carcinoma cell lines, as well as nine pairs of renal cell carcinoma and matched tumor-adjacent renal tissues were examined using reverse transcription-PCR and Western blot. Moreover, SAM68 protein expression and localization in 241 clinicopathologically characterized renal cell carcinoma samples were examined by immunohistochemistry. Prognostic and diagnostic associations were examined by statistical analyses.

RESULTS

SAM68 was markedly overexpressed in renal cell carcinoma cell lines and renal cell carcinoma tissues at both the transcriptional and translational levels. Immunohistochemical analysis revealed high SAM68 protein expression in 129 of the 241 (53.5%) paraffin-embedded archival renal cell carcinoma specimens. Moreover, there was a significant correlation between SAM68 expression and pathologic stage (P < 0.001), T classification (P = 0.003), N classification (P = 0.001), M classification (P = 0.006), and Fuhrman grade (P < 0.001). Patients with higher SAM68 expression had shorter overall survival time than patients with lower SAM68 expression, and the cytoplasmic localization of SAM68 significantly correlated with clinicopathologic grade and outcome. Multivariate analysis indicated that SAM68 protein overexpression and cytoplasmic localization were independent predictors for poor survival of renal cell carcinoma patients.

CONCLUSIONS

Our results suggest that SAM68 could represent a novel and useful prognostic marker for renal cell carcinoma. High SAM68 expression and cytoplasmic localization are associated with poor overall survival in renal cell carcinoma patients.

A multidisciplinary approach to the management of urologic malignancies: does it influence diagnostic and treatment decisions?

OBJECTIVE

It is recognized that multidisciplinary teams may improve management decisions for patients with malignancies. We prospectively studied the effect of such a multidisciplinary approach on the diagnosis and treatment decisions of patients newly presenting with urologic malignancies.

METHODS

Two hundred sixty-nine consecutive new patients presenting to our institution with an outside diagnosis of a urologic malignancy for diagnostic or treatment considerations (2007-2008). All cases were reviewed and discussed at a tumor board with all members of the different subspecialties present. Reevaluation of the outside diagnostic and treatment plan was undertaken. Based on this team review and approach, patients were classified based on changes in diagnosis and/or treatment.

RESULTS

Cohort was comprised of patients with the diagnosis of cancer of the prostate (34%), bladder (23%), kidney (35%), testicle (5%), and other (1%). Only 35% of patients had no changes in diagnosis or treatment, 38% had a change in diagnosis or treatment, 10% required further analysis (i.e., "other"), and 17% were N/A. Changes in diagnosis were most common in bladder (23%) and renal (17%) cancers. Changes in treatment were most common in bladder cancer (44%), followed by kidney (36%), testicular (29%), then prostate (22%) cancers. A stage effect on diagnostic and treatment considerations was also noted, especially for bladder cancer.

CONCLUSIONS

A multidisciplinary team approach affects the diagnostic and management decisions in a significant number patients with a newly diagnosed urologic malignancy, and thereby seems to have a clinical impact for many of our patients with urologic cancers.