Therapy targeted at vascular endothelial growth factor in metastatic renal cell carcinoma: biology, clinical results and future development

Downstream Targets of VHL/HIF-α Signaling in Renal Clear Cell Carcinoma Progression: Mechanisms and Therapeutic Relevance

The clear cell variant of renal cell carcinoma (ccRCC) is the most common renal epithelial malignancy and responsible for most of the deaths from kidney cancer. Patients carrying inactivating mutations in the Von Hippel-Lindau (VHL) gene have an increased proclivity to develop several types of tumors including ccRCC. Normally, the Hypoxia Inducible Factor alpha (HIF-α) subunits of the HIF heterodimeric transcription factor complex are regulated by oxygen-dependent prolyl-hydroxylation, VHL-mediated ubiquitination and proteasomal degradation. Loss of pVHL function results in elevated levels of HIF-α due to increased stability, leading to RCC progression. While HIF-1α acts as a tumor suppressor, HIF-2α promotes oncogenic potential by driving tumor progression and metastasis through activation of hypoxia-sensitive signaling pathways and overexpression of HIF-2α target genes. One strategy to suppress ccRCC aggressiveness is directed at inhibition of HIF-2α and the associated molecular pathways leading to cell proliferation, angiogenesis, and metastasis. Indeed, clinical and pre-clinical data demonstrated the effectiveness of HIF-2α targeted therapy in attenuating ccRCC progression. This review focuses on the signaling pathways and the involved genes (cyclin D, c-Myc, VEGF-a, EGFR, TGF-α, GLUT-1) that confer oncogenic potential downstream of the VHL-HIF-2α signaling axis in ccRCC. Discussed as well are current treatment options (including receptor tyrosine kinase inhibitors such as sunitinib), the medical challenges (high prevalence of metastasis at the time of diagnosis, refractory nature of advanced disease to current treatment options), scientific challenges and future directions.

RNF7 inhibits apoptosis and sunitinib sensitivity and promotes glycolysis in renal cell carcinoma via the SOCS1/JAK/STAT3 feedback loop

Background

RING finger protein 7 (RNF7) is a highly conserved protein that functions as an E3 ubiquitin ligase. RNF7 overexpression is indicated in multiple human cancers, but its role in renal cell carcinoma (RCC) and the mechanisms underlying how it regulates the initiation and progression of RCC have not been explored.

Methods

Bioinformatics analysis, quantitative reverse-transcription polymerase chain reaction (RT-PCR), and Western blot were conducted to determine the expression of RNF7 in RCC tissues and cell lines. Knockdown and overexpression experiments were performed to examine the effects of RNF7 on cell viability, apoptosis, and glycolysis in vitro and on tumor growth in nude mice in vivo.

Results

The elevated RNF7 expression in tumor tissues of patients with RCC was correlated with poor survival. RNF7 overexpression inhibited apoptosis and promoted glycolysis in vitro and increased tumor growth in vivo by activating the JAK/STAT3 signaling pathway by ubiquitination of SOCS1. Moreover, RNF7 overexpression affected the sensitivity of RCC cells to sunitinib. Finally, STAT3 activation was necessary for transcriptional induction of RNF7.

Conclusion

These results demonstrate that RNF7 inhibited apoptosis, promoted glycolysis, and inhibited sunitinib sensitivity in RCC cells via ubiquitination of SOCS1, thus activating STAT3 signaling. These suggest the potential for targeting the RNF7-SOCS1/JAK/STAT3 pathway for RCC treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11658-022-00337-5.

Reversible Posterior Leukoencephalopathy Syndrome following Sunitinib Therapy: A Case Report and Review of the Literature

Sunitinib is one of the standard targeted therapies used in metastatic renal cell carcinoma. It is generally a reasonably tolerated oral systemic therapy but can be occasionally associated with life-threatening toxicities. We present a case of reversible posterior encephalopathy, which is a rare but recognised side effect of the treatment.

Sunitinib treatment in patients with advanced renal cell cancer: the Brazilian National Cancer Institute (INCA) experience

Purpose:

The aim of this study was to assess the impact of sunitinib treatment in a non-screened group of patients with metastatic renal cell cancer (mRCC) treated by the Brazilian Unified Health System (SUS) at a single reference institution.

Material and Methods:

Retrospective cohort study, which evaluated patients with mRCC who received sunitinib between May 2010 and December 2013.

Results:

Fifty-eight patients were eligible. Most patients were male 41 (71%), with a median age of 58 years. Nephrectomy was performed in 41 (71%) patients with a median interval of 16 months between the surgery and initiation of sunitinib. The most prevalent histological subtype was clear cell carcinoma, present in 52 (91.2%) patients. In 50 patients (86%), sunitinib was the first line of systemic treatment. The main adverse effects were fatigue (57%), hypothyroidism (43%), mucositis (33%) and diarrhea (29%). Grade 3 and 4 adverse effects were infrequent: fatigue (12%), hypertension (12%), thrombocytopenia (7%), neutropenia (5%) and hand-foot syndrome (5%). Forty percent of patients achieved a partial response and 35% stable disease, with a disease control rate of 75%. Median progression free survival was 7.6 months and median overall survival was 14.1 months.

Conclusion:

Sunitinib treatment was active in the majority of patients, especially those with low and intermediate risk by MSKCC score, with manageable toxicity. Survival rates were inferior in this non-screened population with mRCC treated in the SUS.

The contributions of HIF-target genes to tumor growth in RCC

Somatic mutations or loss of expression of tumor suppressor VHL happen in the vast majority of clear cell Renal Cell Carcinoma, and it’s causal for kidney cancer development. Without VHL, constitutively active transcription factor HIF is strongly oncogenic and is essential for tumor growth. However, the contribution of individual HIF-responsive genes to tumor growth is not well understood. In this study we examined the contribution of important HIF-responsive genes such as VEGF, CCND1, ANGPTL4, EGLN3, ENO2, GLUT1 and IGFBP3 to tumor growth in a xenograft model using immune-compromised nude mice. We found that the suppression of VEGF or CCND1 impaired tumor growth, suggesting that they are tumor-promoting genes. We further discovered that the lack of ANGPTL4, EGLN3 or ENO2 expression did not change tumor growth. Surprisingly, depletion of GLUT1 or IGFBP3 significantly increased tumor growth, suggesting that they have tumor-inhibitory functions. Depletion of IGFBP3 did not lead to obvious activation of IGFIR. Unexpectedly, the depletion of IGFIR protein led to significant increase of IGFBP3 at both the protein and mRNA levels. Concomitantly, the tumor growth was greatly impaired, suggesting that IGFBP3 might suppress tumor growth in an IGFIR-independent manner. In summary, although the overall transcriptional activity of HIF is strongly tumor-promoting, the expression of each individual HIF-responsive gene could either enhance, reduce or do nothing to the kidney cancer tumor growth.

Dendritic cell-based vaccination for renal cell carcinoma: challenges in clinical trials

After decades of research, dendritic cell (DC)-based vaccines for renal cell carcinoma have progressed from preclinical rodent models and safety assessments to Phase I/II clinical trials. DC vaccines represent a promising therapy that has produced measurable immunological responses and prolonged survival rates. However, there is still much room to improve in terms of therapeutic efficacy. The key issues that affect the efficiency and reliability of DC therapy include the selection of patients who will respond best to treatment, the proper preparation and administration of DC vaccines, and a combination of DC vaccination with other immune-enhancing therapies (e.g., removal of Tregs, CTLA-4 blockade and lymphodepletion). Additional antiangiogenic agents will hopefully lead to greater survival benefits for patients in early disease stages. This review focuses on the different approaches of DC-based vaccination against renal cell carcinoma and potential strategies to enhance the efficacy of DC vaccination.

Self-Plagiarism

The background and explanation for the retraction of Brian Rini's article from the March 2005 issue of The Oncologist are provided.

Efficacy of large doses of IL-2-activated human leukocyte antigen haploidentical peripheral blood stem cells on refractory metastatic renal cell carcinoma

Traditional immunotherapy for patients with refractory metastatic renal cell carcinoma (RCC) is limited because the tumors themselves induce immunosuppression. The aim of this article was to evaluate the clinical efficacy of the infusion of a high dose of interleukin (IL)-2-activated allogeneic haploidentical peripheral blood stem cells (haplo-PBSCs) in patients with advanced intractable RCC. Ten advanced RCC patients and their haploidentical relatives, who were haplo-PBSC donors, were enrolled in this study. All patients accepted one cycle of activated haplo-PBSCs. The clinical and immunologic responses were evaluated. A range from 2.3 to 5.5×10(10) of activated haplo-PBSCs were harvested after exposure to recombinant human IL-2 (rhIL-2), along with a significant increase in the proportion of natural killer cells and activated lymphocytes (CD69+ and CD25+). Enhanced cytotoxicity of haplo-PBSCs for RCC was also observed. After treatment, 2 (2/10) cases of partial remission, 6 (6/10) cases of stable disease, and 2 (2/10) cases of progressive disease were identified in these 10 patients. The median progression-free survival of the 10 patients was 5.5 months (3-14 months). The adoptive transfusion of IL-2-activated haplo-PBSCs can induce sustained antitumor effects for advanced intractable RCC patients who have had no response to conventional immunotherapy.

Sunitinib therapy for metastatic renal cell carcinoma: recommendations for management of side effects

Sunitinib, a new vascular endothelial growth factor receptor inhibitor, has demonstrated high activity in renal cell carcinoma (RCC) and is now widely used for patients with metastatic disease. Although generally well tolerated and associated with a low incidence of common toxicity criteria grade 3 or 4 toxicities, sunitinib exhibits a distinct pattern of novel side effects that require monitoring and management. This article summarizes the most important side effects and proposes recommendations for their monitoring, prevention and treatment, based on the existing literature and on suggestions made by an expert group of Canadian oncologists. Fatigue, diarrhea, anorexia, oral changes, skin toxicity and hypertension seem to be the most clinically relevant toxicities of sunitinib. Fatigue may be partly related to the development of hypothyroidism during sunitinib therapy for which patients should be observed and, if necessary, treated. Hypertension can be treated with standard antihypertensive therapy and rarely requires treatment discontinuation. Neutropenia and thrombocytopenia usually do not require intervention, in particular no episodes of neutropenic fever have been reported to date. A decrease in left ventricular ejection fraction is a rare, but potentially life-threatening side effect. Because of its metabolism by cytochrome P450 3A4 a number of drugs can potentially interact with sunitinib. Clinical response and toxicity should be carefully observed when sunitinib is combined with either a cytochrome P450 3A4 inducer or inhibitor and doses adjusted as necessary. Knowledge about side effects, as well as the proactive assessment and consistent management of sunitinib-related side effects, is critical to ensure optimal benefit from sunitinib treatment.

The von Hippel-Lindau tumor suppressor protein regulates gene expression and tumor growth through histone demethylase JARID1C

In clear-cell renal cell carcinoma (ccRCC), inactivation of the tumor suppressor von Hippel-Lindau (VHL) occurs in the majority of the tumors and is causal for the pathogenesis of ccRCC. Recently, a large-scale genomic sequencing study of ccRCC tumors revealed that enzymes that regulate histone H3 lysine 4 trimethylation (H3K4Me3), such as JARID1C/KDM5C/SMCX and MLL2, were mutated in ccRCC tumors, suggesting that H3K4Me3 might have an important role in regulating gene expression and tumorigenesis. In this study we report that in VHL-deficient ccRCC cells, the overall H3K4Me3 levels were significantly lower than that of VHL+/+ counterparts. Furthermore, this was hypoxia-inducible factor (HIF) dependent, as depletion of HIF subunits by small hairpin RNA in VHL-deficient ccRCC cells restored H3K4Me3 levels. In addition, we demonstrated that only loss of JARID1C, not JARID1A or JARID1B, abolished the difference of H3K4Me3 levels between VHL-/- and VHL+/+ cells, and JARID1C displayed HIF-dependent expression pattern. JARID1C in VHL-/- cells was responsible for the suppression of HIF-responsive genes insulin-like growth factor-binding protein 3 (IGFBP3), DNAJC12, COL6A1, growth and differentiation factor 15 (GDF15) and density-enhanced phosphatase 1. Consistent with these findings, the H3K4Me3 levels at the promoters of IGFBP3, DNAJC12, COL6A1 and GDF15 were lower in VHL-/- cells than in VHL+/+ cells, and the differences disappeared after JARID1C depletion. Although HIF2α is an oncogene in ccRCC, some of its targets might have tumor suppressive activity. Consistent with this, knockdown of JARID1C in 786-O VHL-/- ccRCC cells significantly enhanced tumor growth in a xenograft model, suggesting that JARID1C is tumor suppressive and its mutations are tumor promoting in ccRCC. Thus, VHL inactivation decreases H3K4Me3 levels through JARID1C, which alters gene expression and suppresses tumor growth.

Increased risk of high-grade hypertension with bevacizumab in cancer patients: a meta-analysis

BACKGROUND

Hypertension is associated with the use of bevacizumab, an angiogenesis inhibitor widely used in cancer therapy. Currently, the risk of severe hypertension associated with bevacizumab is unclear. We performed a systematic review and meta-analysis of published randomized-controlled clinical trials (RCTs) to assess the risk of high-grade hypertension in cancer patients treated with bevacizumab.

METHODS

Databases from PUBMED, the Web of Science, and abstracts presented at the American Society of Clinical Oncology conferences until May 2009 were searched to identify relevant studies. Eligible studies included prospective RCTs in which bevacizumab was directly compared with controls in cancer patients receiving concurrent antineoplastic therapy. Summary incidence, relative risk (RR), and 95% confidence interval (CI) were calculated employing a fixed- or random-effects model based upon the heterogeneity of the included studies.

RESULTS

A total of 12,656 patients with a variety of tumors from 20 studies were included for the analysis. The incidence of all-grade hypertension in patients receiving bevacizumab was 23.6% (95% CI: 20.5-27.1) with 7.9% (95% CI: 6.1-10.2) being high-grade (grade 3 or 4). Patients treated with bevacizumab had a significantly increased risk of developing high-grade hypertension with an RR of 5.28 (95% CI: 4.15-6.71, P < 0.001) in comparison with controls. Even though not statistically significant, there was a trend suggesting that bevacizumab may increase the risk of hypertensive crisis (grade 4) with an RR of 3.16 (95% CI: 0.91-10.90). The increased risk of high-grade hypertension was observed in patients receiving bevacizumab at 2.5 mg/kg/week (RR = 4.78, 95% CI: 3.59-6.36) as well as 5 mg/kg/week (RR = 5.39, 95% CI: 3.68-7.90). The risk of high-grade hypertension may vary with tumor types, with RRs ranging from 2.49 (95% CI: 0.94-6.59) in patients with mesothelioma to 14.80 (95% CI: 0.92-238.51) in patients with breast cancer.

CONCLUSION

Bevacizumab may significantly increase the risk of high-grade hypertension in cancer patients. Close monitoring and adequate management are highly recommended to decrease cardiovascular complications.

Fasudil-induced hypoxia-inducible factor-1alpha degradation disrupts a hypoxia-driven vascular endothelial growth factor autocrine mechanism in endothelial cells

Hypoxic response of endothelial cells (EC) is an important component of tumor angiogenesis. Especially, hypoxia-inducible factor-1 (HIF-1)-dependent EC-specific mechanism is an essential component of tumor angiogenesis. Recently, the Rho/Rho-associated kinase (ROCK) signaling has been shown to play a key role in HIF-1alpha induction in renal cell carcinoma and trophoblast. The present study was designed to investigate whether low oxygen conditions might modulate HIF-1alpha expression through the Rho/ROCK signaling in human umbilical vascular ECs (HUVEC). Pull-down assay showed that hypoxia stimulated RhoA activity. Under hypoxic conditions, HUVECs transfected with small interfering RNA of RhoA and ROCK2 exhibited decreased levels of HIF-1alpha protein compared with nontargeted small interfering RNA transfectants, whereas HIF-1alpha mRNA levels were not altered. One of ROCK inhibitors, fasudil, inhibited hypoxia-induced HIF-1alpha expression without altering HIF-1alpha mRNA expression. Furthermore, proteasome inhibitor prevented the effect of fasudil on HIF-1alpha expression, and polyubiquitination was enhanced by fasudil. These results suggested that hypoxia-induced HIF-1alpha expression is through preventing HIF-1alpha degradation by activating the Rho/ROCK signaling in ECs. Furthermore, hypoxia induced both vascular endothelial growth factor (VEGF) and VEGF receptor-2 expression through the Rho/ROCK/HIF-1alpha signaling in HUVECs. Thus, augmented VEGF/VEGF receptor-2 autocrine mechanism stimulated HUVEC migration under hypoxic conditions. In summary, the Rho/ROCK/HIF-1alpha signaling is an essential mechanism for hypoxia-driven, VEGF-mediated autocrine loop in ECs. Therefore, fasudil might have the antimigratory effect against ECs in tumor angiogenesis.

Prognostic factors in a prospective series of papillary renal cell carcinoma

OBJECTIVE

To prospectively assess the clinical outcome of a series of papillary renal cell carcinomas (PRCCs) to identify possible prognostic clinical variables and tumour markers, as previous retrospective series of PRCC do not provide unanimous results on the prognostic utility of clinicopathological variables.

PATIENTS AND METHODS

Forty-six patients with PRCC (median follow-up 40 months) diagnosed in one institution from 1989 to 2002 were prospectively followed until May 2006. The pathology was reviewed, the PRCC subtyped (type 1 and 2) and immunohistochemistry assessed for MIB-1, vascular endothelial growth factor (VEGF), CD31 and c-met oncogenic protein, by a referee pathologist. Prognostic values were estimated by fitting a Cox model.

RESULTS

The 5-year survival rate was 49.5%; type 2 histology was predominant and was almost significant in the univariate analysis. Stage and MIB-1 were significant prognostic factors only in the univariate model, while the Cox model identified only the Fuhrman grade as an independent predictor of survival (hazard ratio 3.054; P = 0.007). MET expression, CD31 and VEGF had no prognostic utility.

CONCLUSION

These patients with PRCC followed prospectively fared worse than in previously reported series. The Fuhrman grade was the sole independent predictor of survival.

Ipilimumab (anti-CTLA4 antibody) causes regression of metastatic renal cell cancer associated with enteritis and hypophysitis

The inhibitory receptor CTLA4 has a key role in peripheral tolerance of T cells for both normal and tumor-associated antigens. Murine experiments suggested that blockade of CTLA4 might have antitumor activity and a clinical experience with the blocking antibody ipilimumab in patients with metastatic melanoma did show durable tumor regressions in some patients. Therefore, a phase II study of ipilimumab was conducted in patients with metastatic renal cell cancer with a primary end point of response by Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Two sequential cohorts received either 3 mg/kg followed by 1 mg/kg or all doses at 3 mg/kg every 3 weeks (with no intention of comparing cohort response rates). Major toxicities were enteritis and endocrine deficiencies of presumed autoimmune origin. One of 21 patients receiving the lower dose had a partial response. Five of 40 patients at the higher dose had partial responses (95% confidence interval for cohort response rate 4% to 27%) and responses were seen in patients who had previously not responded to IL-2. Thirty-three percent of patients experienced a grade III or IV immune-mediated toxicity. There was a highly significant association between autoimmune events (AEs) and tumor regression (response rate=30% with AE, 0% without AE). CTLA4 blockade with ipilimumab induces cancer regression in some patients with metastatic clear cell renal cancer, even if they have not responded to other immunotherapies. These regressions are highly associated with other immune-mediated events of presumed autoimmune origin by mechanisms as yet undefined.

Ipilimumab (anti-CTLA4 antibody) causes regression of metastatic renal cell cancer associated with enteritis and hypophysitis

The inhibitory receptor CTLA4 has a key role in peripheral tolerance of T cells for both normal and tumor-associated antigens. Murine experiments suggested that blockade of CTLA4 might have antitumor activity and a clinical experience with the blocking antibody ipilimumab in patients with metastatic melanoma did show durable tumor regressions in some patients. Therefore, a phase II study of ipilimumab was conducted in patients with metastatic renal cell cancer with a primary end point of response by Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Two sequential cohorts received either 3 mg/kg followed by 1 mg/kg or all doses at 3 mg/kg every 3 weeks (with no intention of comparing cohort response rates). Major toxicities were enteritis and endocrine deficiencies of presumed autoimmune origin. One of 21 patients receiving the lower dose had a partial response. Five of 40 patients at the higher dose had partial responses (95% confidence interval for cohort response rate 4% to 27%) and responses were seen in patients who had previously not responded to IL-2. Thirty-three percent of patients experienced a grade III or IV immune-mediated toxicity. There was a highly significant association between autoimmune events (AEs) and tumor regression (response rate=30% with AE, 0% without AE). CTLA4 blockade with ipilimumab induces cancer regression in some patients with metastatic clear cell renal cancer, even if they have not responded to other immunotherapies. These regressions are highly associated with other immune-mediated events of presumed autoimmune origin by mechanisms as yet undefined.

Sunitinib malate for the treatment of metastatic renal cell carcinoma and gastrointestinal stromal tumors

BACKGROUND

Sunitinib was approved by the US Food and Drug Administration (FDA) on January 26, 2006, for the treatment of metastatic renal cell carcinoma (mRCC) and gastrointestinal stromal tumor (GIST) in patients who have failed to respond to imatinib or were unable to tolerate it.

OBJECTIVE

This article reviews the pharmacology, pharmacokinetics, and pharmacodynamics of sunitinib; potential drug interactions; and the results of clinical trials evaluating its efficacy and tolerability.

METHODS

Pertinent literature was identified by searches of MEDLINE (1966-January 31, 2007), the American Society of Clinical Oncology abstracts database (2000-2007 annual meetings/symposia and previous meetings), and the FDA Web site (October 2006). Search terms included, but were not limited to, sunitinib, SUl1248, renal cell carcinoma, gastrointestinal stromal tumor, pharmacology, pharmacokinetic, adverse events, and clinical trial. Additional publications were found by scanning the reference lists of the identified articles.

RESULTS

Sunitinib is a potent inhibitor of multiple tyrosine kinase receptors. Its Tmax is reached within 6 to 12 hours, and food does not appear to affect its bioavailability. Sunitinib is metabolized by cytochrome P450 (CYP) 3A4 to an active metabolite, SU12662, which is further metabolized by CYP3A4 to an inactive moiety. The parent compound and active metabolite have similar biochemical activity and potency and reach similar plasma concentrations. Sunitinib and SU12662 have a tl/2 of 40 to 60 hours and 80 to 110 hours, respectively. Steady-state concentrations of both active entities are reached after 10 to 14 days of therapy. In a Phase III trial comparing sunitinib with interferon-alfa (IFN-00 as first-line therapy for mRCC, sunitinib was associated with a median progression-free survival of 11 months, compared with 5 months with IFN-cz (P < 0.001). A randomized, double-blind, placebo-controlled trial evaluating sunitinib as second-line therapy for GIST found a median time to progression of 28.9 weeks in the sunitinib arm, compared with 7 weeks in the placebo arm (hazard ratio = 0.28; P < 0.001). In Phase II trials, sunitinib also had anti-tumor activity in patients with breast cancer, neuroendocrine tumors, and non-small cell lung cancer. Further evaluation in these tumors, as well as in patients with acute myelogenous leukemia, may lead to expanded indications. The approved dose of sunitinib is 50 mg/d PO for 4 weeks, followed by a 2-week rest; this pattern is repeated until tumor progression or the occurrence of intolerable adverse effects. The most common clinical toxicities attributable to sunitinib include diarrhea, mucositis/stomatitis, hypertension, rash, skin discoloration, and altered taste, whereas commonly occurring laboratory abnormalities have been seen in association with gastrointestinal toxicity, renal toxicity, and hematologic toxicity. Of grade 3/4 toxicities occurring with sunitinib (which are relatively uncommon [<10%]), those that are clinically important include hypertension, diarrhea, fatigue, and hand-foot syndrome.

CONCLUSIONS

Sunitinib is a multiple tyrosine kinase receptor inhibitor approved for the treatment of mRCC and GIST. Evidence for long-term clinical benefit in renal cell cancer and other tumors awaits the results of ongoing trials.

Evaluation of peri-operative peripheral and renal venous levels of pro- and anti-angiogenic factors and their relevance in patients with renal cell carcinoma

OBJECTIVE

To evaluate peri-operative peripheral and renal venous plasma levels of vascular endothelial growth factor (VEGF), platelet-derived growth factor type BB (PDGF-BB), transforming growth factor (TGF)-beta1, endostatin, and thrombospondin-1 (TSP-1) in relation to pathological variables and prognosis, as pro- and anti-angiogenic factors are important for tumour growth and treatment of patients with renal cell carcinoma (RCC).

PATIENTS AND METHODS

The study included 74 consecutive patients with sporadic RCC who had tumour nephrectomy. Peripheral venous blood was drawn 1 day before, immediately and 1, 3 and 5 days after surgery. Renal venous blood was collected in a subgroup of 33 patients during surgery. The variables were analysed using quantitative enzyme-linked immunoassay kits, and associated with pathological variables and disease-specific survival.

RESULTS

Soon after surgery, peripheral venous VEGF, PDGF-BB and TGF-beta1 levels were decreased, whereas endostatin levels were significantly increased. Renal venous VEGF, PDGF-BB and TGF-beta1 levels were higher than in the general venous blood pool. Renal venous VEGF levels were correlated with tumour diameter and associated with grade and vascular invasion. After a mean follow-up of 30 months, higher peripheral preoperative, early peripheral postoperative and renal venous VEGF levels were associated with a poorer prognosis. However, in a multivariate analysis only Tumour-Node-Metastasis stage and Eastern Cooperative Oncology Group performance status were independent prognosticators of disease-specific survival.

CONCLUSIONS

Circulating pro- and anti-angiogenic factors change early after nephrectomy. VEGF, PDGF-BB and TGF-beta1 are higher in the renal vein than in the general venous blood pool. Higher renal venous and peripheral levels of VEGF might be associated with a poorer prognosis.

Variable penetrance of a consensus classification scheme for renal cell carcinoma

OBJECTIVES

To evaluate the penetrance of the new pathologic standard of care, we characterized the temporal trends in histologic subtype-specific kidney cancer incidence rates. Molecular genetics have refined our understanding of kidney cancer, such that kidney cancer is now recognized as a family of tumors with distinct molecular and clinical characteristics. The histologic classification of kidney cancer has been revised to reflect this new paradigm.

METHODS

Using the Surveillance, Epidemiology, and End Results Program, we identified incident cases from 1983 to 2002. Tumor histologic types were assigned, using the International Classification of Disease-Oncology codes. The histologic-specific incidence rates were calculated and directly age-adjusted to the 2000 U.S. population.

RESULTS

The histologic type was available for 40,813 cases. Subsequent to the Heidelberg consensus conference, the rate of papillary histologic types rose appropriately from 0.02 in 1998 to 0.89 in 2002 per 100,000 U.S. population, and the incidence of granular cell histologic types remained relatively stable (0.22 to 0.14 cases per 100,000), despite its exclusion as a unique histologic subtype. Paradoxically, the incidence of chromophobe tumors decreased during this interval (0.03 to 0.003 cases per 100,000).

CONCLUSIONS

Following the publication of the Heidelberg classification scheme, we have described the differential changes in incidence rates for newly described histologic variants. Our results suggest incomplete penetration of these guidelines. The continued reporting of granular cell histologic types is particularly noteworthy, given that it is no longer recognized as a distinct histologic subtype. Proper categorization of the histologic subtype (eg, chromophobe, papillary, clear cell) is imperative, because it may confer useful information regarding the prognosis, response to adjuvant treatment, and eligibility for clinical trials.

Immunohistochemical Expression of Hypoxia Inducible Factor-1α and its Downstream Molecules in Sarcomatoid Renal Cell Carcinoma

PURPOSE

Sarcomatoid renal cell carcinomas, highly aggressive variants of renal cell carcinoma subtypes, often present with or develop metastases soon after the primary diagnosis. Most metastatic cases do not respond to immunotherapy or aggressive chemotherapy. Recently targeted therapies, particularly those targeting hypoxia inducible pathway molecules, have been tested clinically on metastatic clear cell renal cell carcinoma with promising initial results. No such studies are available on sarcomatoid renal cell carcinoma. We investigated the hypoxia inducible pathway marker immunohistochemical expression profile, and any potential therapeutic implications that such expression may have, in these tumors.

MATERIALS AND METHODS

Immunohistochemical staining for hypoxia inducible factor-1alpha, glucose transporter 1, carbonic anhydrase IX and vascular endothelial growth factor was performed in 22 clear cell and 12 nonclear cell sarcomatoid renal cell carcinomas. The immunoreactivity in the tumors was graded from 0 to 3+ (0-no staining, 1+-1% to 25% cells positive, 2+-26% to 50% cells positive and 3+-greater than 50% cells positive). The results were then compared with various clinical parameters to assess for associations.

RESULTS

Most clear cell renal cell carcinomas over expressed (2+ or 3+) hypoxia inducible factor-1alpha (in 59%), carbonic anhydrase IX (95%), glucose transporter 1 (91%) and vascular endothelial growth factor (95%). None of the nonclear cell sarcomatoid renal cell carcinomas showed 2+ or 3+ expression of hypoxia inducible factor-1alpha, carbonic anhydrase IX or glucose transporter 1, but 92% showed diffuse positivity for vascular endothelial growth factor. Over expression of carbonic anhydrase IX showed no association with survival, unlike that reported in (nonsarcomatoid) clear cell renal cell carcinoma. There was significant discordance in the staining grades among hypoxia inducible factor-1alpha, carbonic anhydrase IX and glucose transporter 1 in clear cell renal cell carcinoma, suggesting that mechanisms other than hypoxia inducible pathway may be involved in some sarcomatoid clear cell renal cell carcinoma.

CONCLUSIONS

Hypoxia inducible pathway markers continue to be over expressed in sarcomatoid clear cell renal cell carcinoma, and can be of diagnostic usefulness in such high grade tumors. Over expression of vascular endothelial growth factor in the clear and nonclear cell groups raises the possibility that vascular endothelial growth factor targeted therapies may have a role in the management of sarcomatoid renal cell carcinoma, and deserve further investigation.

Sunitinib: from rational design to clinical efficacy

Sunitinib (SU011248) is an oral small molecular tyrosine kinase inhibitor that exhibits potent antiangiogenic and antitumor activity. Tyrosine kinase inhibitors such as SU6668 and SU5416 (semaxanib) demonstrated poor pharmacologic properties and limited efficacy; therefore, sunitinib was rationally designed and chosen for its high bioavailability and its nanomolar-range potency against the antiangiogenic receptor tyrosine kinases (RTKs)--vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR). Sunitinib inhibits other tyrosine kinases including, KIT, FLT3, colony-stimulating factor 1 (CSF-1), and RET, which are involved in a number of malignancies including small-cell lung cancer, GI stromal tumors (GISTs), breast cancer, acute myelogenous leukemia, multiple endocrine neoplasia types 2A and 2B, and familial medullary thyroid carcinoma. Sunitinib demonstrated robust antitumor activity in preclinical studies resulting not only in tumor growth inhibition, but tumor regression in models of colon cancer, non-small-cell lung cancer, melanoma, renal carcinoma, and squamous cell carcinoma, which were associated with inhibition of VEGFR and PDGFR phosphorylation. Clinical activity was demonstrated in neuroendocrine, colon, and breast cancers in phase II studies, whereas definitive efficacy has been demonstrated in advanced renal cell carcinoma and in imatinib-refractory GISTs, leading to US Food and Drug Administration approval of sunitinib for treatment of these two diseases. Studies investigating sunitinib alone in various tumor types and in combination with chemotherapy are ongoing. The clinical benchmarking of this small-molecule inhibitor of members of the split-kinase domain family of RTKs will lead to additional insights regarding the biology, potential biomarkers, and clinical utility of agents that target multiple signaling pathways in tumor, stromal, and endothelial compartments.

Risks of proteinuria and hypertension with bevacizumab, an antibody against vascular endothelial growth factor: systematic review and meta-analysis

BACKGROUND

Angiogenesis inhibitors have emerged as an effective targeted therapy in the treatment of patients with many cancers. One of the most widely used angiogenesis inhibitors is bevacizumab, a neutralizing antibody against vascular endothelial growth factor. The overall risk of proteinuria and hypertension in patients with cancer on bevacizumab therapy is unclear. We performed a systematic review and meta-analysis of published clinical trials of bevacizumab to quantify the risk of proteinuria and hypertension.

METHODS

The databases MEDLINE (OVID, 1966 to June 2006) and Web of Science and abstracts presented at the American Society of Clinical Oncology annual meetings from 2004 through 2006 were searched to identify relevant studies. Eligible studies were randomized controlled trials of patients with cancer treated with bevacizumab that described the incidence of proteinuria and hypertension. Relative risk (RR) was calculated by using the fixed-effects model.

RESULTS

A total of 1,850 patients were included in the 7 trials identified from the literature. Bevacizumab was associated with a significant increased risk of proteinuria (RR, 1.4 with low-dose bevacizumab; 95% confidence interval [CI], 1.1 to 1.7; RR, 2.2 with high dose; 95% CI, 1.6 to 2.9). Hypertension also was increased significantly among patients receiving bevacizumab (RR, 3.0 for low dose; 95% CI, 2.2 to 4.2; RR, 7.5 for high dose; 95% CI, 4.2 to 13.4).

CONCLUSION

There was a significant dose-dependent increase in risk of proteinuria and hypertension in patients with cancer who received bevacizumab.

A phase II study of a 5T4 oncofoetal antigen tumour-targeted superantigen (ABR-214936) therapy in patients with advanced renal cell carcinoma

In a phase II study, 43 renal cell carcinoma patients were treated with individualised doses of ABR-214936; a fusion of a Fab recognising the antigen 5T4, and Staphylococcal enterotoxin A. Drug was given intravenously on 4 consecutive days, treatment was repeated 1 month later. Treatment was associated with moderate fever and nausea, but well tolerated. Of 40 evaluable patients, 28 had disease control at 2 months, and at 4 months, one patient showed partial response (PR) and 16 patients stable disease. Median survival, with minimum follow-up of 26 months was 19.7 months with 13 patients alive to date. Stratification by the Motzer's prognostic criteria highlights prolonged survival compared to published expectation. Patients receiving higher drug exposure had greater disease control and lived almost twice as long as expected, whereas the low-exposure patients survived as expected. Sustained interleukin-2 (IL-2) production after a repeated injection appears to be a biomarker for clinical effect, as the induced-IL-2 level on the day 2 of treatment correlated with survival. The high degree of disease control and the prolonged survival suggest that this treatment can be effective. These findings will be used in the trial design for the next generation of drug, with reduced antigenicity and toxicity.

Principles and therapeutic implications of angiogenesis, vasculogenesis and arteriogenesis

The vasculature is the first organ to arise during development. Blood vessels run through virtually every organ in the body (except the avascular cornea and the cartilage), assuring metabolic homeostasis by supplying oxygen and nutrients and removing waste products. Not surprisingly therefore, vessels are critical for organ growth in the embryo and for repair of wounded tissue in the adult. Notably, however, an imbalance in angiogenesis (the growth of blood vessels) contributes to the pathogenesis of numerous malignant, inflammatory, ischaemic, infectious and immune disorders. During the last two decades, an explosive interest in angiogenesis research has generated the necessary insights to develop the first clinically approved anti-angiogenic agents for cancer and blindness. This novel treatment is likely to change the face of medicine in the next decade, as over 500 million people worldwide are estimated to benefit from pro- or anti-angiogenesis treatment. In this following chapter, we discuss general key angiogenic mechanisms in health and disease, and highlight recent developments and perspectives of anti-angiogenic therapeutic strategies.

A brief symptom index for advanced renal cell carcinoma

Background

Our objective was to test a brief, symptom index for advanced renal cell carcinoma, a disease affecting over 38,000 Americans each year and often diagnosed in late stages.

Methods

We conducted secondary data analyses on patient-reported outcomes of 209 metastatic renal cell carcinoma patients participating in a Phase III clinical trial. Patient-reported outcomes, obtained from the FACT-Biological Response Modifier (FACT-BRM) scale, were available at baseline, 2, and 8 weeks. We analyzed data from eight FACT-BRM items previously identified by clinical experts to represent the most important symptoms of advanced renal cell carcinoma. Items comprising this index assess nausea, pain, appetite, perceived sickness, fatigue and weakness, with higher scores indicating fewer symptoms. We determined reliability and validity of the index and estimated a minimally important difference.

Results

The index had excellent internal reliability at all three time points (alphas ≥ 0.83). Baseline scores were able to discriminate patients across Karnofsky performance status, number of metastatic sites, and risk group categories (ps < .01). Mean index scores declined over time likely indicative of the toxic nature of the administered treatments. Distribution- and anchor-based methods converged on a minimally important difference estimate of 2 to 3 points.

Conclusion

The 8-item index of patient-reported symptoms of renal cell carcinoma appears to be a psychometrically sound measure. It is a brief, reliable, and valid measure that can easily be adapted for use in clinical trials and observational studies.

New treatment approaches in metastatic renal cell carcinoma

PURPOSE OF REVIEW

Recent developments in the understanding of the molecular biology of renal cell carcinoma have led to the development of several biologic agents with different mechanisms of action. In 2005, promising results have been observed especially in second-line therapy following cytokine failures and in 2006 more mature data with regard to time to progression and overall survival should be available. This review, analyzing basic translational research principles, will summarize the available evidence with a glimpse of the future therapeutic approaches in renal cell carcinoma.

RECENT FINDINGS

Vascular endothelial growth factor- and platelet-derived growth factor receptor-inhibiting drugs (SU11248, Bay 43-9006, Bevacizumab, AG-013736, etc.) report time to progression ranging between 4 and 9 months and variable benefits in overall survival. Confirmatory studies are ongoing regarding other novel treatments (CCI-779, Infliximab, PTK-787).

SUMMARY

In renal cell carcinoma, there is a strong rationale for targeting multiple pathways and particularly angiogenesis. Vascular endothelial growth factor- and platelet-derived growth factor receptor-inhibiting drugs have been rapidly approved in the second-line setting and will soon be used as first-line therapy. In the next years, translational/clinical research will provide evidence for combination strategies to improve upon the results of the biologic agents and hopefully offer more hope to patients with renal cell carcinoma.

Adjuvant Therapy of Renal Cell Carcinoma

Metastatic renal cell carcinoma (RCC) has a highly variable natural history and carries a dismal prognosis. Unlike many other tumors, RCC is generally unresponsive to cytotoxic, hormonal, and radiation adjuvant therapies after cytoreductive surgery. Different modalities of treatment have been tried and tested with modest success. Until recently, only immunotherapies such as interleukin-2 and interferon-alpha have been shown to provide a response, albeit in a minority of patients and often with severe treatment-associated toxicities. Other adjuvant therapies, such as active specific immunotherapy with Bacillus Calmette-Guerin and autologous renal tumor cell vaccines, have not provided alternative solutions. Recent approaches include heat-shock protein peptide complex 96 vaccine and cG250 monoclonal antibody therapy. Novel targeted therapies have been developed using our knowledge of the molecular genetics that belie RCC. This culminated in sorafenib and sunitinib, the first Food and Drug Administration-approved drugs for RCC in more than a decade in the United States. The future will see further trials being carried out in the development of targeted therapies with emphasis placed on patient selection. Staging systems will need to be updated to integrate molecular biomarkers, which could potentially act not just as diagnostic and prognostic predictors, but also as tools for appropriate patient selection for treatment. In the future, this could potentially lead us to our ultimate goal of personalized medicine.

Phase 1 trial of the antiangiogenic peptide ATN-161 (Ac-PHSCN-NH(2)), a beta integrin antagonist, in patients with solid tumours

To evaluate the toxicity, pharmacological and biological properties of ATN-161, a five –amino-acid peptide derived from the synergy region of fibronectin, adult patients with advanced solid tumours were enrolled in eight sequential dose cohorts (0.1–16 mg kg⁻¹), receiving ATN-161 administered as a 10-min infusion thrice weekly. Pharmacokinetic sampling of blood and urine over 7 h was performed on Day 1. Twenty-six patients received from 1 to 14 4-week cycles of treatment. The total number of cycles administered to all patients was 86, without dose-limiting toxicities. At dose levels above 0.5 mg kg⁻¹, mean total clearance and volume of distribution showed dose-independent pharmacokinetics (PKs). At 8.0 and 16.0 mg kg⁻¹, clearance of ATN-161 was reduced, suggesting saturable PKs. Dose escalation was halted at 16 mg kg⁻¹ when drug exposure (area under the curve) exceeded that associated with efficacy in animal models. There were no objective responses. Six patients received more than four cycles of treatment (>112 days). Three patients received 10 or more cycles (⩾280 days). ATN-161 was well tolerated at all dose levels. Approximately, 1/3 of the patients in the study manifested prolonged stable disease. These findings suggest that ATN-161 should be investigated further as an antiangiogenic and antimetastatic cancer agent alone or with chemotherapy.

Therapeutic Dendritic Cell Vaccination of Patients with Renal Cell Carcinoma

OBJECTIVE

Dendritic cell (DC) vaccination against cancer is a new specific immunotherapeutic approach given with either therapeutic or adjuvant intent. We provide a review of DC vaccination as a treatment for metastatic renal cell carcinoma (RCC).

METHOD

A total of 197 patients with metastatic RCC were treated with DC vaccination in 14 phase I/II clinical trials. Different vaccine preparations, administration routes, and treatment schedules have been tested in these trials. Clinical response and immune response were analysed.

RESULTS

Seventy-three (37%) patients had clinical response with 4 complete responses, 8 partial responses and 61 disease stabilisations, whereas 4 patients had mixed response, but most of these responses have not been transformed into durable clinical effects. Immune responses were observed in a subset of the treated patients but were not always associated with a clinical response. Only mild toxicity was observed in these trials.

CONCLUSION

DC vaccination therapy in patients with metastatic RCC is currently experimental but the results are encouraging with achievement of tumour regression and induction of antigen-specific immune response combined with minimal toxicity in a subset of the treated patients. Future emphasis should be placed on therapy in the adjuvant setting because patients with minimal residual disease are more likely to benefit from the treatment. Combination approaches with DC vaccination and immune-enhancing therapies or antiangiogenic therapy should be further investigated to develop new and more efficient treatment strategies for patients with RCC.

Molecular targets in melanoma from angiogenesis to apoptosis

Angiogenesis is a hallmark of melanoma progression. Antiangiogenic agents have been infrequently tested in patients with advanced melanoma. Experience with most other cancers suggests that single-agent application of angiogenic inhibitors is unlikely to have substantial clinical antitumor activity in melanoma. It is more likely that combinations of antiangiogenic agents with either chemotherapy or other targeted therapy will be needed to produce significant clinical benefit. In melanoma, numerous cellular pathways important to cell proliferation, apoptosis, or metastases have recently been shown to be activated. Activation occurs through specific mutations (B-RAF, N-RAS, and PTEN) or changes in expression levels of various proteins (PTEN, BCL-2, NF-kappaB, CDK2, and cyclin D1). Agents that block these pathways are rapidly entering the clinical setting, including RAF inhibitors (sorafenib), mitogen-activated protein kinase inhibitors (PD0325901), mammalian target of rapamycin inhibitors (CCI-779), and farnesyl transferase inhibitors (R115777) that inhibit N-RAS and proteasome inhibitors (PS-341) that block activation of nuclear factor-kappaB (NF-kappaB). It will be a challenge to evaluate these agents alone, in combination with each other, or with chemotherapy in patients with melanoma. Trials with large populations of biologically ill-defined tumors run the risk of missing clinical antitumor activity that is important for a particular yet-to-be-defined subset of patients. To rationally and optimally develop these targeted agents, it will be critical to adequately test for the presence of the presumed cellular target in tumor specimens and the effect of therapy on the proposed target (biological response). Investigators in this field will need to carefully plan these trials so that at the end of the day, we learn from both the failures and successes of targeted therapy.

Lessons from phase III clinical trials on anti-VEGF therapy for cancer

In randomized phase III trials two anti-vascular endothelial growth factor (VEGF) approaches have yielded survival benefit in patients with metastatic cancer. In one approach, the addition of bevacizumab, a VEGF-specific antibody, to standard chemotherapy improved overall survival in colorectal and lung cancer patients and progression-free survival in breast cancer patients. In the second approach, multitargeted tyrosine kinase inhibitors that block VEGF receptor and other kinases in both endothelial and cancer cells, demonstrated survival benefit in gastrointestinal stromal tumor and renal-cell-carcinoma patients. By contrast, adding bevacizumab to chemotherapy failed to increase survival in patients with previously treated and refractory metastatic breast cancer. Furthermore, addition of vatalanib, a kinase inhibitor developed as a VEGF receptor-selective agent, to chemotherapy did not show a similar benefit in metastatic colorectal cancer patients. These contrasting responses raise critical questions about how these agents work and how to combine them optimally. We summarize three of the many potential mechanisms of action of anti-VEGF agents, and also discuss progress relating to the identification of potential biomarkers for anti-VEGF-agent efficacy in humans.

Allogeneic haematopoietic stem cell transplantation for metastatic renal carcinoma in Europe

BACKGROUND

An allogeneic antitumour effect has been reported for various cancers. We evaluated the experience of allogeneic haematopoietic stem cell transplantation (HSCT) for renal cell carcinoma (RCC) in 124 patients from 21 European centres.

PATIENTS AND METHODS

Reduced intensity conditioning and peripheral blood stem cells from an HLA-identical sibling (n = 106), a mismatched related (n = 5), or an unrelated (n = 13) donor were used. Immunosuppression was cyclosporine alone, or combined with methotrexate or mycophenolate mofetil. Donor lymphocyte infusions (DLI) were given to 42 patients. The median follow-up was 15 (range 3-41) months.

RESULTS

All but three patients engrafted. The cumulative incidence of moderate to severe, grades II-IV acute GVHD was 40% and for chronic GVHD it was 33%. Transplant-related mortality was 16% at one year. Complete (n = 4) or partial (n = 24) responses, median 150 (range 42-600) days post-transplant, were associated with time from diagnosis to HSCT, mismatched donor and acute GVHD II-IV. Factors associated with survival included chronic GVHD (hazards ratio, HR 4.12, P < 0.001), DLI (HR 3.39, P < 0.001), <3 metastatic sites (HR 2.61, P = 0.002) and a Karnofsky score >70 (HR 2.33, P = 0.03). Patients (n = 17) with chronic GVHD and given DLI had a 2-year survival of 70%.

CONCLUSION

Patients with metastatic RCC, less than three metastatic locations and a Karnofsky score >70% can be considered for HSCT. Posttransplant DLI and limited chronic GVHD improved the patient survival.

Early renal cell cancer

Renal cell cancer (RCC) mostly arises from the proximal renal tubules and is classified as an adenocarcinoma. The most reliable treatment for RCC is surgical excision; chemotherapy or radiotherapy does not have a practical effect on RCC. In selected patients, immunotherapy, including cytokine administration, has survival benefits. There is no established definition of early RCC. Surgical removal of organ-confined disease (T1 and T2) is likely to achieve tumor-free status leading to good prognosis. Possible definitions, diagnosis and treatment options for T1 and T2 disease are discussed.