Immunotherapy for renal cell carcinoma

ECOG performance status 0 or 1 and symptom classification do not improve the ability to predict renal cell carcinoma-specific survival

OBJECTIVES

We tested and compared the improvement in prognostic ability related to the consideration of either ECOG performance status (ECOGPS) and/or symptom classification (S-CLASS) in renal cell carcinoma specific mortality (RCC-SM) predictions.

METHODS

Univariate and multivariate Cox regression analyses targeted RCC-SM in 2570 RCC patients treated with either partial or radical nephrectomy. The increment in predictive accuracy related to the addition of either ECOGPS, S-CLASS or both was quantified using Harrell's concordance index.

RESULTS

Follow-up ranged from 0.1 to 23 years (median 3.2) and 610 patients (23.7%) died of RCC. In multivariable analyses, ECOGPS and S-CLASS represented independent predictors of RCC-SM. The addition of ECOGPS to established RCC-SM predictors increased the predictive accuracy by 0.3% (p=0.8) versus 0.6% (p=0.5) for S-CLASS versus 0.6% (p=0.5) for both.

CONCLUSIONS

Neither ECOGPS nor S-CLASS improves the ability to predict RCC-SM. Therefore, these variables may be safely omitted when RCC-SM risk is quantified.

Platelet count and preoperative haemoglobin do not significantly increase the performance of established predictors of renal cell carcinoma-specific mortality

OBJECTIVE

Anaemia and/or thrombocytosis were identified as independent predictors of poor survival in renal cell carcinoma (RCC). We tested the extent to which these markers worsen the prognosis in these patients.

METHODS

Analyses targeted 1828 patients with renal cell carcinoma. Univariable, multivariable, and predictive accuracy analyses addressed RCC-specific mortality (RCC-SM).

RESULTS

In univariable and multivariable analyses, both platelet count and preoperative haemoglobin level were statistically significant predictors of RCC-SM. However, neither platelet count nor preoperative haemoglobin level increased the combined multivariable accuracy of established RCC-SM (predictive accuracy gain=0.3%) predictors.

CONCLUSIONS

Patients who present with severe anaemia or elevated platelets are at no higher risk of RCC-SM than that related to their stage, grade, histologic subtype, and Eastern Cooperative Oncology Group-Performance Status.

Preliminary analysis of patients with progressive renal cell carcinoma vaccinated with CA9-peptide-pulsed mature dendritic cells

Carbonic anhydrase-IXG250/MN (CA9) is a renal cell carcinoma (RCC)-associated antigen ubiquitously expressed in the clear-cell subtype of RCC. Two CA9-derived peptides have been identified defining a cytotoxic T-lymphocyte epitope and human leukocyte antigen (HLA)-DR epitope, able to induce T-cell responses in vitro. A phase I clinical trial was performed with CA9-peptide-loaded dendritic cells (DCs) in patients with progressive, cytokine-refractory metastatic RCC to assess the safety, toxicity, and induction of CA9-specific immunity. Patients with objective progressive metastatic RCC received 5 vaccinations of mature DCs pulsed with the CA9-derived peptides and keyhole limpet hemocyanine (KLH). Peripheral blood was collected at regular intervals, delayed-type hypersensitivity (DTH) was tested at baseline and after the last vaccination, and skin biopsies of positive DTH sites were collected for immunomonitoring purposes. Patients were also monitored for clinical responses. No significant toxicity was observed. All patients developed humoral responses against KLH, and demonstrated DTH conversion. Evaluation of biopsy material suggested an increased influx of T-helper cells. In none of the immunomonitoring assays was evidence for the induction of CA9-peptide-specific immunity observed. No clinical responses were observed. The vaccination of DCs pulsed with KLH and 2 CA9-derived peptides was well tolerated. The lack of induction of CA9-peptide-specific immune responses indicates that this particular vaccine regimen is poor in inducing CA9-peptide-specific immune responses.

Prognostic factors associated with long-term survival in previously untreated metastatic renal cell carcinoma

PURPOSE

To identify prognostic factors (PF) for long-term survival in metastatic renal cell carcinoma (RCC) patients.

METHODS

We retrospectively reviewed a metastatic RCC database at the Cleveland Clinic Foundation consisting of 358 previously untreated patients who were enrolled in institutional review board-approved clinical trials of immunotherapy and/or chemotherapy at our institution from 1987 to 2002. In order to identify patient characteristics associated with long-term survival, we compared 226 'short-term' survivors [defined as overall survival (OS) <2 years] with 31 'long-term' survivors (OS >or=5 years).

RESULTS

Using logistic regression models, four adverse PF were identified as independent predictors of long-term survival: hemoglobin less than the lower limit of normal, greater than two metastatic sites, involved kidney (left), and Eastern Cooperative Oncology Group (ECOG) performance status (PS). Using the number of poor prognostic features present, three distinct risk groups could be identified. Patients with 0 or 1 adverse prognostic feature present had an observed likelihood of long-term survival of 32% (21/66) compared with 9% (8/91) for patients with two adverse features present and only 1% (1/93) for patients with more than two adverse features.

CONCLUSIONS

Independent predictors of long-term survival in previously untreated metastatic RCC include baseline hemoglobin level, number of involved sites, involved kidney, and ECOG PS. Incorporation of these factors into a simple prognostic scoring system enables three distinct groups of patients to be identified.

Treatment of patients with metastatic renal cell cancer: a RAND Appropriateness Panel

BACKGROUND

New developments in the treatment of patients with metastatic renal cell cancer (MRCC) have suggested a need to reevaluate the role of systemic therapies. The authors convened a panel of medical and urologic oncologists to rate the appropriateness of the main options.

METHODS

The authors used the RAND/University of California-Los Angeles Appropriateness Method to evaluate systemic therapy options and cytoreductive nephrectomy. After a comprehensive literature review, an expert panel rated the appropriateness of systemic options (108 permutations) and cytoreductive nephrectomy (24 permutations) for patients with MRCC.

RESULTS

The appropriateness evaluation indicated that 27.3% of permutations were rated "appropriate," 46.9% were rated "inappropriate," and 25.8% were rated "uncertain." There was a high rate of agreement (95%). Sunitinib and sorafenib were rated appropriate for patients with low-to-moderate risk regardless of prior treatment. Temsirolimus was rated appropriate for first-line therapy for higher risk patients. Interferon-alpha and low-dose interleukin-2 were rated inappropriate or uncertain. In patients who received prior immunotherapy, cytokines were rated inappropriate. In all permutations for evaluating systemic therapy, enrollment into an investigational trial was considered appropriate, treatment with bevacizumab was uncertain, and thalidomide was inappropriate regardless of risk status or prior therapy. For good surgical risk patients with planned immunotherapy, nephrectomy was rated appropriate in patients who had limited metastatic burden regardless of tumor-related symptoms and in symptomatic patients regardless of metastatic burden. Only the most favorable combination of surgical risk, metastatic burden, and symptoms generated an "appropriate" rating for patients with planned targeted therapy.

CONCLUSIONS

The current results begin the process of defining an appropriate role for cytokines, newer targeted therapies, and surgery in the treatment of MRCC.

C-reactive protein is an informative predictor of renal cell carcinoma-specific mortality

BACKGROUND

C-reactive protein (CRP) represents a promising prognostic variable in patients with sporadic renal cell carcinoma (RCC). It was hypothesized that CRP can improve the prognostic ability of standard RCC-specific mortality (RCC-SM) predictors in patients treated with nephrectomy for all stages of RCC.

METHODS

Radical nephrectomy was performed in 314 patients from 2 European centers. Life table, Kaplan-Meier, and Cox regression analyses addressed RCC-SM. Covariates included age, gender, TNM stage, tumor size, Fuhrman grade, and histologic subtype.

RESULTS

The median survival of the cohort was 19.9 years. Age ranged from 10 to 77 years. Most patients were male (69%). T-stages were distributed as follows: T1-121 (38.7%), T2-45 (14.4%), T3-140 (44.7%), T4-7 (2.2%). CRP values ranged from 1.0 to 358.0 mg/L (mean 40.9, median 11.0 mg/L). In multivariable analyses, CRP was an independent predictor of RCC-SM (P = .003). The consideration of CRP in the multivariable model increased the predictive accuracy by 3.7% (P < .001). Moreover, the model with CRP performed 2.4% and 4.6% better than the UCLA Integrated Staging System (UISS) at, respectively, 2 and 5 years.

CONCLUSIONS

CRP represents an informative predictor of RCC-SM. Its routine use could allow better risk stratification and risk-adjusted follow-up of RCC patients.

Prognostic ability of simplified nuclear grading of renal cell carcinoma

BACKGROUND

The Fuhrman grading system is an established predictor of survival in patients with renal cell carcinoma (RCC). The predictive accuracy of various Fuhrman grading schemes was tested with the intent of improving the prediction of RCC-specific survival (RCC-SS).

METHODS

The analyses targeted 5453 patients from 14 institutions. Univariable, multivariable, and predictive accuracy analyses addressed RCC-SS. The statistical significance of the gain in predictive accuracy was quantified with the Mantel-Haenszel test.

RESULTS

The median follow-up time was 4.5 years. In both univariable and multivariable analyses, Fuhrman grade achieved independent predictor status regardless of the coding scheme. When Fuhrman grade was not considered in multivariable analyses, the predictive accuracy was 83.8%. Addition of Fuhrman grade to the multivariable model resulted in predictive accuracy gains of 0.8% for all 3 grading schemes tested.

CONCLUSION

Fuhrman grade must to be considered when RCC-SS is assessed. However, modified or conventional Fuhrman grading schemes perform equally well as the conventional grading system.

Chemotherapy for non-clear-cell renal cell carcinoma

Clear-cell carcinoma is the most common histopathologic subtype of kidney tumors. Consequently, clinical trials for advanced-stage kidney cancer have focused on patients with clear-cell carcinoma and not on the less common subtypes, including papillary, chromophobe, collecting-duct carcinoma, and sarcomatoid-variant tumors. Whereas immunotherapy has constituted the standard treatment for patients with clear-cell renal cell carcinoma (RCC), it does not appear to have activity in the management of patients with other histologic subtypes. Novel therapies, including those targeting the vascular endothelial growth factor pathway, have recently demonstrated significant activity in clear-cell RCC. Historically, chemotherapy has shown limited activity in advanced-stage RCC; however, clinical trials to date have failed to individualize treatment based on histologic subtype. In this article, we will review the literature and present our experience with the use of chemotherapy in patients with non-clear-cell kidney cancer by histologic subtype.

Serum levels of vascular endothelial growth factor (VEGF) and endostatin in renal cell carcinoma patients compared to a control group

OBJECTIVES

Renal cell carcinoma (RCC) is a vascularised neoplasm. The importance of the angiogenic process in its growth and metastatic spreading is widely recognised. We assessed serum levels of endogenous endostatin and vascular endothelial growth factor (VEGF) in RCC patients and healthy volunteers, and evaluated the factors' prognostic role for patients' survival, distinguishing histologic subtypes with respect to correlation with tumour stage, grade, and size.

METHODS

We considered 146 consecutive patients with RCC and 110 healthy volunteers. Serum samples from all subjects were analysed for endostatin and VEGF by using competitive enzyme immunoassays. RCC samples were compared with serum from the control group and with clinicopathologic factors and clinical outcome.

RESULTS

Mean age was 63 years (range: 37-85 years) in RCC patients and 62 years (range: 23-88 years) in the control group. VEGF levels (median: 3.6 ng/ml+/-6.97; range: 0-48.4 ng/mL) were significantly higher in RCC patients, compared with controls (p=0.001). Endostatin levels did not differ significantly between the two groups (p=0.9) without correlation between endostatin and VEGF levels (p=0.09). No significant difference was found in the endostatin levels among the histologic subtypes (p=0.973) and VEGF (p=0.232). The median follow-up was 27 months (range: 1-57 months).

CONCLUSIONS

Serum VEGF levels are elevated in RCC patients, compared with controls, and do not correlate significantly with circulating endostatin levels. No difference in preoperative serum VEGF and endostatin levels among the different histologic subtypes was found. In multivariate analysis VEGF and endostatin failed to be prognostic; only tumour stage and grade remained independent predictors of survival.

Expression of RASSF1A, an epigenetically silenced tumor suppressor, overcomes resistance to apoptosis induction by interferons

Resistance of human renal cell carcinoma (RCC) and melanoma to the apoptosis-inducing effects of IFNs was postulated to result from epigenetic silencing of genes by DNA methylation, a common feature of human cancers. To reverse silencing, 5-AZA-deoxycytidine (5-AZA-dC) or selective depletion of DNA methyltransferase 1 (DNMT1) by phosphorothioate oligonucleotide antisense (DNMT1 AS) were employed in cells resistant (<5% terminal deoxynucleotidyl transferase-mediated nick-end labeling positive) to apoptosis induction by IFN-alpha2 and IFN-beta (ACHN, SK-RC-45, and A375). 5-AZA-dC and DNMT1 AS similarly depleted available DNMT1 protein and, at doses that did not cause apoptosis alone, resulted in apoptotic response to IFNs. The proapoptotic tumor suppressor RASSF1A was reactivated by DNMT1 inhibitors in all three cell lines. This was associated with demethylation of its promoter region. IFNs augmented RASSF1A protein expression after reactivation by DNMT1 inhibition. In IFN-sensitive WM9 melanoma cells, expression of RASSF1A was constitutive but also augmented by IFNs. RASSF1A small interfering RNA reduced IFN-induced apoptosis in WM9 cells and in DNMT1-depleted ACHN cells. Conversely, lentiviral expression of RASSF1A but not transduction with empty virus enabled IFN-induced apoptosis. IFN induced tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and TRAIL-neutralizing antibody inhibited apoptotic response to IFN in RASSF1A-expressing ACHN cells. Accordingly, RASSF1A markedly sensitized to recombinant TRAIL. Normal kidney epithelial cells, although expressing RASSF1A, did not undergo apoptosis in response to IFN or TRAIL but had >400-fold higher TRAIL decoy receptor 1 expression than transduced ACHN cells (real-time reverse transcription-PCR). Results identified RASSF1A as regulated by IFNs and participating in IFN-induced apoptosis at least in part by sensitization to TRAIL.

A clinical trial with chimeric monoclonal antibody WX-G250 and low dose interleukin-2 pulsing scheme for advanced renal cell carcinoma

PURPOSE

WX-G250 is a chimeric monoclonal antibody that binds to carbonic anhydrase IX(G250/MN), which is present on greater than 95% of RCCs of the clear cell subtype. The suggested working mechanism of WX-G250 is by ADCC. Because the number of activated ADCC effector cells can be increased by a low dose interleukin-2 pulsing schedule, a multicenter study was initiated to investigate whether WX-G250 combined with LD-IL-2 could lead to an improved clinical outcome in patients with progressive RCC.

MATERIALS AND METHODS

A total of 35 patients with progressive clear cell RCC received weekly infusions of WX-G250 for 11 weeks combined with a daily LD-IL-2 regimen. Patients were monitored longitudinally for ADCC capacity. Radiological assessment of metastatic lesions was performed at week 16 and regularly until disease progression.

RESULTS

A durable clinical benefit was achieved in 8 of 35 patients (23%), including 3 with a partial response and 5 with stabilization at 24 weeks or greater. Mean survival was 22 months. In general treatment was well tolerated with little toxicity. The number of effector cells increased during treatment but lytic capacity per cell did not increase. ADCC and clinical outcome did not appear to correlate.

CONCLUSIONS

WX-G250 combined with LD-IL-2 in patients with metastatic RCC is safe and well tolerated. With a substantial clinical benefit and a median survival of 22 months in patients with metastatic RCC who have progressive disease at study entry combination therapy showed increased overall survival compared to WX-G250 monotherapy. Survival was at least similar to that of currently used cytokine regimens but with a favorable toxicity profile.

Cytotoxic markers and frequency predict functional capacity of natural killer cells infiltrating renal cell carcinoma

PURPOSE

Renal cell carcinoma harbors high numbers of infiltrating lymphocytes with apparent limited efficacy in tumor control. This study focused on the natural killer (NK) cells infiltrating renal cell carcinoma.

EXPERIMENTAL DESIGN

Tumor-infiltrating lymphocytes (TIL) were isolated from renal cell carcinoma and analyzed for NK cell frequency and phenotype (n = 34). NK cells were enriched and tested for effector function.

RESULTS

Two renal cell carcinoma subtypes were identified, one containing high (>20% of the lymphocyte population, n = 14), the other low (<20%, n = 20), NK cell numbers. NK cells of both groups were noncytolytic ex vivo but differed in CD16 and cytotoxic effector molecule expression as well as in their capacity to acquire cytotoxic activity: The majority of NK cells from tumors with high NK cell content (high NK-TIL) were CD16(bright), whereas few CD16bright NK cells were found in tumors with low NK cell frequencies (low NK-TIL). The CD16 dichotomy correlated with different capacities to develop cytotoxicity after short-term activation with interleukin-2 ex vivo: Low NK-TIL remained noncytolytic against K562 and unresponsive to signals via the activating receptor NKp46 despite expression of receptor and adaptor molecules. In contrast, high NK-TIL acquired cytotoxic function. As described for peripheral CD16bright NK cells, NK cells from high-NK tumors showed high per cell expression of granzyme A, granzyme B, and perforin. NK cells from low NK-TIL resembled CD16(neg/dim) peripheral NK cells with few cytotoxin+ cells and lower expression of perforin.

CONCLUSION

The extent of NK cell infiltration and the expression of markers (CD16 and cytotoxins) predict the functional capacity of NK cells infiltrating renal cell carcinoma and can be used to characterize subgroups of renal cell carcinoma.

Interferon-alpha enhances TRAIL-mediated apoptosis by up-regulating caspase-8 transcription in human hepatoma cells

BACKGROUND/AIMS

IFNalpha is an approved treatment option for patients chronically infected with the hepatitis B and C viruses. Additionally, there is an indication for tumor therapy. The exact mechanisms underlying the antiviral and antitumor effects of IFNalpha are not completely understood. In this study, we investigated if the pro-apoptotic factor caspase-8 is a target gene of IFNalpha signalling.

METHODS

Huh7 hepatoma cells were used for measuring caspase-8 promoter activity in luciferase reporter assays after IFNalpha stimulation. Caspase-8 expression was monitored by RT-PCR, immunoblotting and measurement of enzymatic activity. Functional caspase-8 promoter elements were identified in gelshift assays and by site directed mutagenesis. Caspase-8 was inhibited using siRNA.

RESULTS

IFNalpha treatment induced caspase-8 promoter activity and mRNA expression. We identified a unique promoter element mediating the IFNalpha-dependent increase in caspase-8 transcription. Up-regulation of caspase-8 expression by IFNalpha had no impact on the rate of apoptosis per se. However, co-stimulation with IFNalpha doubled TRAIL-mediated apoptosis and enzymatic caspase-8 activity. The synergistic effect of TRAIL and IFNalpha could be blocked by inhibiting caspase-8 expression.

CONCLUSIONS

We demonstrate that caspase-8 is a target gene of IFNalpha and provide evidence showing that IFNalpha treatment sensitizes cells for apoptosis via enhanced caspase-8 transcription.

Genitourinary malignancies in solid organ transplant recipients

Malignancy is a recognized complication of transplantation. Genitourinary cancers are the second most common tumors in transplant recipients with prostate cancer and renal cell carcinoma the most common. Unlike the more common skin malignancies, genitourinary tumors have a significant impact on both graft and patient survival. Surgical and radiation treatments need to consider the location of heterotopic transplants and administration of chemotherapy may need alteration in light of immunosuppression being used. The major genitourinary malignancies and their management will be reviewed in this article with emphasis on the concerns that arise in a transplant recipient.

Generation of RAGE-1 and MAGE-9 peptide-specific cytotoxic T-lymphocyte lines for transfer in patients with renal cell carcinoma

Renal cell carcinomas (RCCs) are supposed to be immunogenic, and several clinical trials of immunotherapy using tumor lysate-pulsed dendritic cells (DCs) have been performed. We report on the generation of RAGE-1 and MAGE-9 peptide-specific CTL lines. RAGE-1 and MAGE-9 are expressed in 56% and 38% of RCCs. Seven MAGE-9- and 13 RAGE-1-derived peptides were found to be immunogenic in the context of the HLA-A*0201 MHC. CTLs were generated by coculture with peptide-pulsed, activated B cells, which were easily generated in great quantities and displayed functional activity for a prolonged period of time. MAGE-9 and RAGE-1 peptide-specific CTL lines were strictly peptide-specific and displayed high cytotoxic activity not only against peptide-loaded T2 cells but also against HLA-A*0201-positive RCC lines, which naturally express MAGE-9, RAGE-1 or both. Thus, B cells are well suited as APCs for the generation of large numbers of tumor peptide-specific CTLs for adoptive transfer. MAGE-9 as well as RAGE-1 may well provide suitable targets for immunotherapy of RCC.

Sodium Stibogluconate Interacts with IL-2 in Anti-Renca Tumor Action via a T Cell-Dependent Mechanism in Connection with Induction of Tumor-Infiltrating Macrophages

IL-2 therapy results in 10-20% response rates in advanced renal cell carcinoma (RCC) via activating immune cells, in which the protein tyrosine phosphatase Src homology 2 domain-containing phosphatase 1 (SHP-1) is a key negative regulator. Based on finding that sodium stibogluconate (SSG) inhibited SHP-1, the anti-RCC potential and action mechanism of SSG and SSG/IL-2 in combination were investigated in a murine renal cancer model (Renca). Despite its failure to inhibit Renca cell proliferation in cultures, SSG induced 61% growth inhibition of Renca tumors in BALB/c mice coincident with an increase (2-fold) in tumor-infiltrating macrophages (Mphi). A combination of SSG and IL-2 was more effective in inhibiting tumor growth (91%) and inducing tumor-infiltrating Mphi (4-fold), whereas IL-2 alone had little effect. Mphi increases were also detected in the spleens of mice treated with SSG (3-fold) or SSG/IL-2 in combination (6-fold), suggesting a systemic Mphi expansion similar to those in SHP-deficient mice. T cell involvement in the anti-Renca tumor action of the combination was suggested by the observations that the treatment induced spleen IFN-gamma T cells in BALB/c mice, but failed to inhibit Renca tumor growth in athymic nude mice and that SSG treatment of T cells in vitro increased production of IFN-gamma capable of activating tumoricidal Mphi. The SSG and SSG/IL-2 combination treatments were tolerated in the mice. These results together demonstrate an anti-Renca tumor activity of SSG that was enhanced in combination with IL-2 and functions via a T cell-dependent mechanism with increased IFN-gamma production and expansion/activation of Mphi. Our findings suggest that SSG might improve anti-RCC efficacy of IL-2 therapy by enhancing antitumor immunity.

Generating Renal Cancer-Reactive T Cells Using Dendritic Cells (DCs) to Present Autologous Tumor

Dendritic cells (DCs) have been used as professional antigen-presenting cells in vitro to prime T-cell responses. In this study, we generated both CD8+ and CD4+ renal cell carcinoma (RCC)-reactive T cells using a completely autologous system of DCs presenting engulfed whole-tumor cells. We compared DCs presenting RCC tumor cells in different preparations and found ultraviolet-irradiated apoptotic tumor cells to be more immunogenic than necrotic tumor cells or live untreated tumor cells in generating tumor-reactive T cells. In analyzing the T cells generated in this fashion, a CD8+ RCC-reactive T-cell clone generated from a patient recognized an epitope derived from fibroblast growth factor 5 in the context of human leukocyte antigen (HLA) B44*02. CD4+ T cells generated from another patient recognized multiple allogeneic RCC lines expressing HLA-DRbeta1*04, indicating a common shared tumor antigen presented by HLA-DRbeta1*04. The technique of using DCs to present whole-tumor cells can consistently generate both CD4+ and CD8+ RCC-reactive T cells for use in both antigen identification and therapeutic protocols.

Response of papillary renal cell carcinoma in a solitary kidney to high dose interleukin therapy

Kidney cancer affects 36 000 Americans annually and is responsible for nearly 12 000 deaths every year in the US. Treatment with interleukin-2 (IL-2), the only FDA approved therapy for patients with advanced kidney cancer, is associated with a 10% complete response and a 12% partial response. To date, clear cell renal carcinoma has been the only histological type associated with response to IL-2-based therapy. In the current report, we describe a response to IL-2 therapy in a patient with type I papillary renal carcinoma.

Metastatic renal cell carcinoma presenting as multiple pleural tumours

A 66-year-old man was admitted with dyspnoea. Chest X-ray and chest computed tomography (CT) demonstrated a left-sided pleural effusion and multiple tumours, suggesting malignant mesothelioma in the left pleural space, but there were no pulmonary lesions. However, abdominal CT revealed a right renal tumour. An ultrasonography-guided needle biopsy of the pleural mass provided evidence of metastatic renal cell carcinoma (RCC). The pleural lesions dramatically decreased in size following right radical nephrectomy and subsequent interferon-alpha treatment. While the thorax is a frequently affected site of RCC, sole pleural metastases are rare and are often secondary to lung involvement. Batson's plexus, a network of vertebral valve-less veins with multiple connections, is likely responsible for the contralateral pleural metastases of RCC.

Retinoic acid and the histone deacetylase inhibitor trichostatin a inhibit the proliferation of human renal cell carcinoma in a xenograft tumor model

PURPOSE

Therapy for advanced renal cell carcinoma (RCC) is ineffective in the majority of patients. We have previously reported that retinoid-induced up-regulation of retinoic acid receptor beta (RARbeta) correlated with antitumor effects in RCCs. Recent studies show that there is a reduction in the level of RARbeta2 expression in cancer cells due in part to histone hypoacetylation. Therefore, we tested whether combining histone deacetylase inhibitors with retinoic acid (RA) would restore RARbeta2 receptor expression, leading to increased growth inhibition in RCC cells.

EXPERIMENTAL DESIGN

Cell proliferation, Western blot, and reverse transcription-PCR analyses of two RA-resistant RCC cell lines, SK-RC-39 and SK-RC-45, were assessed in the presence of all-trans retinoic acid (ATRA), trichostatin A (TSA), or the combination of ATRA and TSA. Analysis of apoptosis was also done on SK-RC-39 cells treated with these combinations. Additionally, a xenograft tumor model (SK-RC-39) was used in this study to investigate the efficacy of a liposome-encapsulated, i.v. form of ATRA (ATRA-IV) plus TSA combination therapy.

RESULTS

Enhanced inhibition of the proliferation of RCC cell lines and of tumor growth in a xenograft model was observed with the combination of ATRA plus TSA. Reactivation of RARbeta2 mRNA expression was observed in SK-RC-39 and SK-RC-45 cells treated with TSA alone or TSA in combination with ATRA. A partial G0-G1 arrest and increased apoptosis were observed with SK-RC-39 cells on treatment with ATRA and TSA.

CONCLUSIONS

The combination of ATRA and the histone deacetylase inhibitor TSA elicits an additive inhibition of cell proliferation in RCC cell lines. These results indicate that ATRA and histone deacetylase inhibitor therapies should be explored for the treatment of advanced RCC.

Immunotherapy in metastatic renal cell carcinoma

Metastatic renal cell carcinoma has a poor prognosis. Conventional therapies such as chemotherapy, radiation or hormonal treatment have hardly any effect on the progression of this disease. As renal cell carcinoma seems to be an immunogenic tumor, several immunotherapeutic approaches with different response rates have been developed since the early 1990s. We present an overview of various immunotherapeutic approaches such as cytokine-based regimes, with and without different cytotoxic chemotherapy, of metastatic renal cell carcinoma. In addition, local therapies (e.g. inhalation of interleukin-2) are reviewed.

Chemotherapy in metastatic renal cell cancer

Currently, there is no standard treatment for patients with advanced renal cell carcinoma (RCC) who do not respond to or progress after transient remission to first-line immunotherapy. At the end of the 1990s, no single chemotherapeutic drug, alone or in combination with interleukin-2 (IL-2) or interferon-alfa (IFN), had shown activity beyond the one expected by immunotherapy alone. New drugs on the market such as the pyrimidine analog gemcitabine or taxane-based chemotherapeutics may show promising tumor activity in combination with targeted therapy, but this has to be substantiated in upcoming trials. There is a great need to develop effective systemic therapy for advanced MRCC and to evaluate the efficacy of new drugs in clinical trials.

Renal cell carcinoma: review of novel single-agent therapeutics and combination regimens

A search of the Medline database and ASCO 2003 conference proceedings was conducted to identify clinical trials currently underway using single-agent therapy for renal cell carcinoma (RCC). Combination trials were identified using the ASCO 2003 conference proceedings. Fourteen single-agent therapies employing different mechanisms of action were identified in the published literature: imatinib mesylate (Gleevec); bevacizumab (Avastin); thalidomide (Thalomid); gefitinib (ZD1839) (Iressa); cetuximab (IMC-C225) (Erbitux); bortezomib (PS-341) (Velcade); HSPPC-96 (Oncophage); BAY 59-8862; ABT-510; G250; CCI-779; SU5416; PTK/ZK; and ABX-EGF. Six distinct fields of clinical research have emerged: monoclonal antibodies, small molecules, vaccines, second-generation taxanes, nonapeptides and immunomodulators. Five combination regimens, primarily biological response modifiers (interleukin-2 or interferon-alpha), chemotherapy- or thalidomide-based, were identified. All therapies demonstrated acceptable toxicity profiles. Clinical benefit was assessed based on each study's reported criteria: antitumor response (regression or stability) ranged from 5% to 71%. In the past several years, significant advances in the underlying biological mechanisms of RCC, particularly the role of tumor angiogenesis, have permitted the design of molecularly targeted therapeutics. Based on preliminary and limited studies, combination therapies offer the greatest clinical benefit in the management of this malignancy, although additional basic research is still warranted.

Active chemotherapy for sarcomatoid and rapidly progressing renal cell carcinoma

BACKGROUND

Immunotherapy is generally ineffective in patients with sarcomatoid renal cell carcinoma (RCC) and in patients with rapidly progressive metastatic or locally recurrent disease, with a median time to progression of approximately 2 months and a median survival of 4-7 months. Gemcitabine-based regimens have modest antitumor activity, whereas doxorubicin is often used to treat sarcomatoid RCC. Based on the antitumor activity of doxorubicin and gemcitabine in collecting duct carcinoma of the kidney, the authors used this combination to treat selected patients with sarcomatoid or rapidly progressing RCC.

METHODS

Eighteen patients (11 males and 7 females; median age, 53 years; range, 31-81 years) with RCC (56% sarcomatoid; 44% other) were treated at 2 institutions in a collaborative study that was not institutional review board reviewed. Seven patients received previous treatment with interferon or interleukin-2. Sites of metastases included the lung, soft tissue, bone, liver, and brain with 88% of patients having > or = 3 sites of disease. Treatment consisted of doxorubicin (50 mg/m2) and gemcitabine (1500 or 2000 mg/m2) every 2-3 weeks with granulocyte-colony-stimulating factor support.

RESULTS

A median of 5 courses was administered (range, 2-12 cycles). Therapy was well tolerated with no Grade 4 toxicities. Two patients had a complete response, five had a partial response, three had a mixed response, and one had stable disease. The median duration of response was 5 months (range, 2-21+ months).

CONCLUSIONS

These data suggested that the combination of doxorubicin and gemcitabine has antitumor activity in patients with sarcomatoid RCC or with rapidly progressing RCC. A prospective investigation of this combination in RCC is warranted.

The tumour suppressor geneCEACAM1 is completely but reversibly downregulated in renal cell carcinoma

CEACAM1 acts as a tumour suppressor in various epithelial tumours. On the other hand, de novo expression of CEACAM1 is strongly associated with reduced disease-free survival of melanoma and non-small cell lung carcinoma patients. Since effector functions of natural killer and T cells are inhibited by homophilic CEACAM1 interaction, immune escape could be responsible for the poor prognosis of these patients. Here, we describe CEACAM1 expression in normal kidney, renal adenomas and renal cell carcinomas (RCC) using a novel antibody generated by genetic immunization. In normal kidney, CEACAM1 was found in epithelial cells of proximal tubules and in endothelial cells. In contrast, tumour cells of 30 clear cell, three chromophobic, and two chromophilic RCCs were completely devoid of CEACAM1. Renal adenomas also lacked CEACAM1 expression. Similarly, RCC cell lines CaKi1, CaKi2, A498, and RCC26 exhibited no or low-level CEACAM1 expression. However, CEACAM1 expression was transiently induced in A498 cells upon contact with allogeneic CD8+ T cells, mediated at least in part by interferon-gamma. Furthermore, the majority of tumour-infiltrating T and NK cells expressed CEACAM1 upon stimulation. Thus, transient expression of the tumour suppressor CEACAM1 by tumour cells and subsequent homophilic interaction with CEACAM1 on tumour-infiltrating lymphocytes could represent a novel immune escape mechanism in RCC.

Endothelin axis expression is markedly different in the two main subtypes of renal cell carcinoma

BACKGROUND

The endothelin axis has been implicated in cancer growth, angiogenesis, and metastasis, but to the authors' knowledge the expression of endothelin genes has not been defined in renal cell carcinoma (RCC).

METHODS

Tissue specimens were harvested from both normal and tumor-affected regions at the time of radical nephrectomy from 35 patients with RCC (22 with clear cell RCC [ccRCC] and 13 with papillary RCC [PRCC]). Real-time reverse transcriptase-polymerase chain reaction analysis determined the expression profile of the preproendothelins (PPET-1, PPET-2, and PPET-3), the endothelin receptors (ET(A) and ET(B)), and the endothelin-converting enzymes (ECE-1 and ECE-2).

RESULTS

PPET-1 was found to be up-regulated in ccRCC tumor specimens and down-regulated in PRCC tumor specimens. ET(A) was significantly down-regulated in PRCC tumor specimens. ECE-1 was expressed in all tissue specimens at comparable levels, with moderate but significant elevation in normal tissue specimens associated with PRCC. Of the other genes, PPET-2 and ET(B) were expressed in all tissue specimens and no differences were observed between tumor subtypes or tumor-affected and normal tissue specimens, whereas PPET-3 and ECE-2 were present in all tissue specimens but were barely detectable.

CONCLUSIONS

The endothelin axis was expressed differently in the two main subtypes of RCC and appeared to match macroscopic features commonly observed in these tumors (i.e., high expression of PPET-1 in hypervascular ccRCC contrasted against low PPET-1 and ET(A) expression in hypovascular PRCC). The presence of ECE-1 mRNA in these tissue specimens suggested that active endothelin ligands were present, indicating endothelin axis activity was elevated in ccRCC compared with normal kidney, but impaired in PRCC. The current study provided further evidence that it is not appropriate to consider ccRCC and PRCC indiscriminately in regard to treatment.

Low frequency of HLA haplotype loss associated with loss of heterozygocity in chromosome region 6p21 in clear renal cell carcinomas

HLA class I loss or downregulation is a widespread mechanism used by tumor cells to avoid tumor recognition by cytotoxic T lymphocytes favoring tumor immune escape. Multiple molecular mechanisms are responsible for these altered HLA class I tumor phenotypes. It has been described in different epithelial tumors that loss of heterozygosity (LOH) at chromosome region 6p21.3 is a frequent mechanism that leads to HLA haplotype loss, ranging between 40 and 50%, depending on the tumor entity analyzed. Here we have tested the frequency of LOH at 6p21 chromosome region in Renal Cell Carcinomas (RCC) of the clear cell and chromophobe subtype. A low frequency of HLA haplotype loss (6.6%) was found in clear cell RCC. These data significantly differ from those reported in other epithelial tumors. In contrast, in RCC of chromophobe subtype this frequency was 10 times higher (3 out of 5 cases analyzed). These results indicate that LOH at 6p21.3 is not a frequent mechanism that leads to HLA class I abnormalities in clear cell RCC. In addition, the chromophobe RCC subtypes differ not only in histopathological criteria but also in the frequency of LOH-mediating HLA class I alterations. These results might help to understand the significantly different biological behavior of both RCC subtypes.

Immunological effects of granulocyte-macrophage colony-stimulating factor and autologous tumor vaccine in patients with renal cell carcinoma

PURPOSE

Biological therapy for renal cell carcinoma (RCC) uses agents that mobilize immune effector cells which are able to recognize and destroy cancer. We evaluated the effects of weekly then monthly autologous tumor vaccine combined with daily granulocyte macrophage-colony stimulating factor (GM-CSF) in patients with RCC as a method of stimulating antigen presenting cells.

MATERIALS AND METHODS

Eligible patients with pathological stage II to IV RCC were entered into this pilot study. Autologous tumor vaccine (0.5 to 1 x 107 irradiated tumor cells) admixed with 250 microg GM-CSF per vaccine was given subcutaneously weekly for 4 weeks and then monthly for 4 months. GM-CSF (125 microg/m2) was given subcutaneously for 13 days after vaccine injection 1 and injections 4 to 8. Treatment related tumor specific CD4 and CD8 positive T cell precursors were assessed.

RESULTS

A total of 22 patients were entered into this study. Patients were stratified by bulk of disease (group 1, 9 patients with micrometastatic disease, and group 2, 13 patients with macrometastatic disease). In general treatment was well tolerated. Of 9 patients in group 1 7 remained disease-free after nephrectomy. In group 2, 6 patients had stable (46.2%) and 7 patients had progressive disease (53.8%). Statistically significant treatment related increases in CD4 (p = 0.028) and CD8 (p = 0.018) positive tumor specific T cell precursors were observed for the entire group of patients. Changes in CD4 and CD8 positive precursors correlated significantly with each other (p = 0.0001). This correlation was seen in the 2 patient subpopulations as well (group 1 p = 0.003, group 2 p = 0.013). Patients with minimal disease, and with changes in CD4 and CD8 positive tumor specific T cell precursors greater than the median appeared to have an improved time to progression as well as a survival benefit.

CONCLUSIONS

GM-CSF and autologous vaccine can be given safely in combination to patients with renal cell cancer. We observed treatment related changes in tumor specific circulating lymphocyte populations.