First-line therapy for adults with advanced renal cell carcinoma: a systematic review and network meta-analysis

BACKGROUND

Since the approval of tyrosine kinase inhibitors, angiogenesis inhibitors and immune checkpoint inhibitors, the treatment landscape for advanced renal cell carcinoma (RCC) has changed fundamentally. Today, combined therapies from different drug categories have a firm place in a complex first-line therapy. Due to the large number of drugs available, it is necessary to identify the most effective therapies, whilst considering their side effects and impact on quality of life (QoL).

OBJECTIVES

To evaluate and compare the benefits and harms of first-line therapies for adults with advanced RCC, and to produce a clinically relevant ranking of therapies. Secondary objectives were to maintain the currency of the evidence by conducting continuous update searches, using a living systematic review approach, and to incorporate data from clinical study reports (CSRs).

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, conference proceedings and relevant trial registries up until 9 February 2022. We searched several data platforms to identify CSRs.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) evaluating at least one targeted therapy or immunotherapy for first-line treatment of adults with advanced RCC. We excluded trials evaluating only interleukin-2 versus interferon-alpha as well as trials with an adjuvant treatment setting. We also excluded trials with adults who received prior systemic anticancer therapy if more than 10% of participants were previously treated, or if data for untreated participants were not separately extractable.

DATA COLLECTION AND ANALYSIS

All necessary review steps (i.e. screening and study selection, data extraction, risk of bias and certainty assessments) were conducted independently by at least two review authors. Our outcomes were overall survival (OS), QoL, serious adverse events (SAEs), progression-free survival (PFS), adverse events (AEs), the number of participants who discontinued study treatment due to an AE, and the time to initiation of first subsequent therapy. Where possible, analyses were conducted for the different risk groups (favourable, intermediate, poor) according to the International Metastatic Renal-Cell Carcinoma Database Consortium Score (IMDC) or the Memorial Sloan Kettering Cancer Center (MSKCC) criteria. Our main comparator was sunitinib (SUN). A hazard ratio (HR) or risk ratio (RR) lower than 1.0 is in favour of the experimental arm.

MAIN RESULTS

We included 36 RCTs and 15,177 participants (11,061 males and 4116 females). Risk of bias was predominantly judged as being 'high' or 'some concerns' across most trials and outcomes. This was mainly due to a lack of information about the randomisation process, the blinding of outcome assessors, and methods for outcome measurements and analyses. Additionally, study protocols and statistical analysis plans were rarely available. Here we present the results for our primary outcomes OS, QoL, and SAEs, and for all risk groups combined for contemporary treatments: pembrolizumab + axitinib (PEM+AXI), avelumab + axitinib (AVE+AXI), nivolumab + cabozantinib (NIV+CAB), lenvatinib + pembrolizumab (LEN+PEM), nivolumab + ipilimumab (NIV+IPI), CAB, and pazopanib (PAZ). Results per risk group and results for our secondary outcomes are reported in the summary of findings tables and in the full text of this review. The evidence on other treatments and comparisons can also be found in the full text. Overall survival (OS) Across risk groups, PEM+AXI (HR 0.73, 95% confidence interval (CI) 0.50 to 1.07, moderate certainty) and NIV+IPI (HR 0.69, 95% CI 0.69 to 1.00, moderate certainty) probably improve OS, compared to SUN, respectively. LEN+PEM may improve OS (HR 0.66, 95% CI 0.42 to 1.03, low certainty), compared to SUN. There is probably little or no difference in OS between PAZ and SUN (HR 0.91, 95% CI 0.64 to 1.32, moderate certainty), and we are uncertain whether CAB improves OS when compared to SUN (HR 0.84, 95% CI 0.43 to 1.64, very low certainty). The median survival is 28 months when treated with SUN. Survival may improve to 43 months with LEN+PEM, and probably improves to: 41 months with NIV+IPI, 39 months with PEM+AXI, and 31 months with PAZ. We are uncertain whether survival improves to 34 months with CAB. Comparison data were not available for AVE+AXI and NIV+CAB. Quality of life (QoL) One RCT measured QoL using FACIT-F (score range 0 to 52; higher scores mean better QoL) and reported that the mean post-score was 9.00 points higher (9.86 lower to 27.86 higher, very low certainty) with PAZ than with SUN. Comparison data were not available for PEM+AXI, AVE+AXI, NIV+CAB, LEN+PEM, NIV+IPI, and CAB. Serious adverse events (SAEs) Across risk groups, PEM+AXI probably increases slightly the risk for SAEs (RR 1.29, 95% CI 0.90 to 1.85, moderate certainty) compared to SUN. LEN+PEM (RR 1.52, 95% CI 1.06 to 2.19, moderate certainty) and NIV+IPI (RR 1.40, 95% CI 1.00 to 1.97, moderate certainty) probably increase the risk for SAEs, compared to SUN, respectively. There is probably little or no difference in the risk for SAEs between PAZ and SUN (RR 0.99, 95% CI 0.75 to 1.31, moderate certainty). We are uncertain whether CAB reduces or increases the risk for SAEs (RR 0.92, 95% CI 0.60 to 1.43, very low certainty) when compared to SUN. People have a mean risk of 40% for experiencing SAEs when treated with SUN. The risk increases probably to: 61% with LEN+PEM, 57% with NIV+IPI, and 52% with PEM+AXI. It probably remains at 40% with PAZ. We are uncertain whether the risk reduces to 37% with CAB. Comparison data were not available for AVE+AXI and NIV+CAB.

AUTHORS' CONCLUSIONS

Findings concerning the main treatments of interest comes from direct evidence of one trial only, thus results should be interpreted with caution. More trials are needed where these interventions and combinations are compared head-to-head, rather than just to SUN. Moreover, assessing the effect of immunotherapies and targeted therapies on different subgroups is essential and studies should focus on assessing and reporting relevant subgroup data. The evidence in this review mostly applies to advanced clear cell RCC.

Biological aspects in controlling angiogenesis: current progress

All living beings continue their life by receiving energy and by excreting waste products. In animals, the arteries are the pathways of these transfers to the cells. Angiogenesis, the formation of the arteries by the development of pre-existed parental blood vessels, is a phenomenon that occurs naturally during puberty due to certain physiological processes such as menstruation, wound healing, or the adaptation of athletes' bodies during exercise. Nonetheless, the same life-giving process also occurs frequently in some patients and, conversely, occurs slowly in some physiological problems, such as cancer and diabetes, so inhibiting angiogenesis has been considered to be one of the important strategies to fight these diseases. Accordingly, in tissue engineering and regenerative medicine, the highly controlled process of angiogenesis is very important in tissue repairing. Excessive angiogenesis can promote tumor progression and lack of enough angiogensis can hinder tissue repair. Thereby, both excessive and deficient angiogenesis can be problematic, this review article introduces and describes the types of factors involved in controlling angiogenesis. Considering all of the existing strategies, we will try to lay out the latest knowledge that deals with stimulating/inhibiting the angiogenesis. At the end of the article, owing to the early-reviewed mechanical aspects that overshadow angiogenesis, the strategies of angiogenesis in tissue engineering will be discussed.

Small Molecule Kinase Inhibitor Drugs (1995-2021): Medical Indication, Pharmacology, and Synthesis

The central role of dysregulated kinase activity in the etiology of progressive disorders, including cancer, has fostered incremental efforts on drug discovery programs over the past 40 years. As a result, kinase inhibitors are today one of the most important classes of drugs. The FDA approved 73 small molecule kinase inhibitor drugs until September 2021, and additional inhibitors were approved by other regulatory agencies during that time. To complement the published literature on clinical kinase inhibitors, we have prepared a review that recaps this large data set into an accessible format for the medicinal chemistry community. Along with the therapeutic and pharmacological properties of each kinase inhibitor approved across the world until 2020, we provide the synthesis routes originally used during the discovery phase, many of which were only available in patent applications. In the last section, we also provide an update on kinase inhibitor drugs approved in 2021.

CDK4/6 and MAPK-Crosstalk as Opportunity for Cancer Treatment

Despite the development of targeted therapies and novel inhibitors, cancer remains an undefeated disease. Resistance mechanisms arise quickly and alternative treatment options are urgently required, which may be partially met by drug combinations. Protein kinases as signaling switchboards are frequently deregulated in cancer and signify vulnerable nodes and potential therapeutic targets. We here focus on the cell cycle kinase CDK6 and on the MAPK pathway and on their interplay. We also provide an overview on clinical studies examining the effects of combinational treatments currently explored for several cancer types.

Analysis of the factors influencing the survival time of patients with sarcomatoid renal cell carcinoma

The aim of the present study was to identify the factors influencing the survival time of patients with sarcomatoid renal cell carcinoma (SRCC). Between January 2000 and September 2017, a total of 21 patients were enrolled, all of whom were diagnosed with SRCC. In total, eight prognostic factors were analyzed using the Kaplan-Meier estimator, a log-rank test and Cox's proportional hazards model. The log-rank test results revealed that there was a significant association between the proportion of sarcoma elements and survival time of patients with SRCC (P<0.05). In addition, there was a significant association between post-operative drug treatment and SRCC survival time (P<0.05). The results of the Kaplan-Meier estimate demonstrated that the survival curve of post-operative drug treatment was significantly greater compared with the survival curve of patients who did not undergo drug treatment (P<0.05). The survival curve of patients with a proportion of sarcoma elements <50% was significantly greater compared with the survival curve of patients with a proportion of sarcoma elements ≥50% (P<0.05). Furthermore, the Cox's proportional hazards model revealed that the mortality risk in post-operative patients without drug treatment was 5.822 times greater compared with that of patients with drug treatment (P<0.05). Mortality risk in patients with a proportion of sarcoma elements ≥50% was 4.682 times higher compared with that of patients with sarcoma elements <50% (P<0.05). Finally, post-operative drug therapy was revealed to be a protective factor which significantly affected the survival time of patients with SRCC [risk ratio (RR)=0.172], in addition to the proportion of sarcoma elements ≥50% (RR=4.682). In conclusion, drug therapy should be promoted upon patient diagnosis with SRCC and attention should be given to the proportion of sarcomatoid components.

A Phase II Trial of Sorafenib and Dacarbazine for Leiomyosarcoma, Synovial Sarcoma, and Malignant Peripheral Nerve Sheath Tumors

BACKGROUND

Sorafenib and dacarbazine have low single-agent response rates in metastatic sarcomas. As angiogenesis inhibitors can enhance the efficacy of chemotherapy, we investigated the combination of sorafenib and dacarbazine in select sarcoma subtypes.

MATERIALS AND METHODS

Patients with leiomyosarcoma (LMS), synovial sarcoma (SS), or malignant peripheral nerve sheath tumors (MPNST) with up to two previous lines of therapy and adequate hepatic, renal, and marrow function received 3-week cycles of sorafenib at 400 mg oral twice daily and dacarbazine 1,000 mg/m2 intravenously (later reduced to 850 mg/m2). Patients were evaluated for response every 6 weeks. The primary objective was to determine the disease control rate (DCR) of sorafenib plus dacarbazine in the selected sarcoma subtypes.

RESULTS

The study included 37 patients (19 female); median age was 55 years (range 26-87); and histologies included LMS (22), SS (11), and MPNST (4). The DCR was 46% (17/37). Median progression-free survival was 13.4 weeks. The RECIST response rate was 14% (5/37). The Choi response rate was 51% (19/37). Median overall survival was 13.2 months. Of the first 25 patients, 15 (60%) required dacarbazine dose reductions for hematologic toxicity, with one episode of grade 5 neutropenic fever. After reducing the starting dose of dacarbazine to 850 mg/m2, only 3 of the final 12 (25%) patients required dose reduction.

CONCLUSION

This phase II study met its primary endpoint with an 18-week DCR of 46%. The clinical activity of dacarbazine plus sorafenib in patients with these diagnoses is modest.

IMPLICATIONS FOR PRACTICE

Metastatic soft tissue sarcomas are a heterogeneous group of relatively rare malignancies. Most patients are treated with cytotoxic chemotherapy or targeted therapy in the form of tyrosine kinase inhibitors. Response rates are relatively low, and there is a need for better therapies. This clinical trial demonstrates that combining a cytotoxic therapy (dacarbazine) with an antiangiogenic small molecule (sorafenib) is feasible and associated with favorable disease-control rates; however, it also increases the potential for significant toxicity.

Receptor tyrosine kinases in PI3K signaling: The therapeutic targets in cancer

The phosphoinositide 3-kinase (PI3K) pathway, one of the most commonly activated signaling pathways in human cancers, plays a crucial role in the regulation of cell proliferation, differentiation, and survival. This pathway is usually activated by receptor tyrosine kinases (RTKs), whose constitutive and aberrant activation is via gain-of-function mutations, chromosomal rearrangement, gene amplification and autocrine. Blockage of PI3K pathway by targeted therapy on RTKs with tyrosine kinases inhibitors (TKIs) and monoclonal antibodies (mAbs) has achieved great progress in past decades; however, there still remain big challenges during their clinical application. In this review, we provide an overview about the most frequently encountered alterations in RTKs and focus on current therapeutic agents developed to counteract their aberrant functions, accompanied with discussions of two major challenges to the RTKs-targeted therapy in cancer - resistance and toxicity.

Safety, tolerability and pharmacokinetics of the fibroblast growth factor receptor inhibitor AZD4547 in Japanese patients with advanced solid tumours: a Phase I study

Background AZD4547 is a potent, oral, highly selective fibroblast growth factor receptor (FGFR) inhibitor in clinical development for treating tumours with a range of FGFR aberrations, including FGFR mutations, amplifications and fusions. Methods This open-label, Phase I, multicentre study (NCT01213160) evaluated the safety, pharmacokinetics, and preliminary antitumour efficacy (RECIST v1.1) of AZD4547 monotherapy in Japanese patients with advanced solid tumours. Part A was a dose-escalation part; Part B was a dose-expansion part in patients with FGFR-amplified tumours, confirmed by fluorescence in situ hybridization. Results Thirty patients enrolled in Part A (dose range: 40 mg twice daily [bid] to 120 mg bid; 160 mg once daily [qd]), four in Part B (80 mg bid). No dose-limiting toxicities were observed and maximum tolerated dose was not determined. Most common adverse events (AEs; any grade) were: dysgeusia (50% of patients); stomatitis (41%); diarrhoea (38%); hyperphosphataemia (38%); dry mouth (35%). Common grade ≥3 AEs were nausea (12% of patients) and neutropenia (9%). No complete or partial responses were observed: 21/30 patients had stable disease ≥4 weeks in Part A, and 1/4 patients had stable disease ≥10 weeks in Part B. Following single and multiple dosing, absorption rate appeared moderate; peak plasma concentrations generally occurred 3-4 h post-dose, then declined biphasically with terminal half-life ~30 h. Steady state was reached by day 8. Compared with single dosing, plasma concentrations were, on average, 2.4- and 3.3- to 5.4-fold higher after qd and bid dosing, respectively. Conclusions AZD4547 was well tolerated in Japanese patients, with best response of stable disease ≥4 weeks.

Computational study on the unbinding pathways of B-RAF inhibitors and its implication for the difference of residence time: insight from random acceleration and steered molecular dynamics simulations

Random acceleration and steered molecular dynamics simulations reveal the unbinding pathway of B-RAF inhibitors and the difference in the residence time.

Design, synthesis and biological evaluation of thiourea and nicotinamide-containing sorafenib analogs as antitumor agents

Thiourea and nicotinamide-containing sorafenib analogs with better antiproliferative and anti-angiogenic activities than sorafenib were well designed and synthesized.

Hand-foot syndrome associated with use of sorafenib in a patient with papillary thyroid cancer: a case report

BACKGROUND

Hand-foot syndrome (HFS), also known as palmar-plantar Erythrodysesthesia (PPE), acral erythema or Burgdorf reaction, is a dermatologic toxic reaction to certain chemotherapies, including sorafenib. A high incidence of adverse events is already described in dermatological clinical trials of this drug, but its use in medical practice, common in the patient with metastatic thyroid carcinoma has not yet been reported. Sorafenib (BAY 43-9006) is an orally administered multi-level kinase inhibitor, approved for treatment of solid tumors such as renal cell carcinoma, hepatocellular carcinoma and recently for metastatic thyroid carcinoma.

CASE PRESENTATION

We report a case of a 29 year old Latin woman diagnosed with papillary thyroid carcinoma, who was initially given a total thyroidectomy, central and bilateral neck lymph node removal followed by a radioiodine therapy. Subsequent evaluation indicated locoregional progressive disease and metastatic involvement in both lungs. Following this, the patient was prescribed 200 mg of sorafenib administered every 12 hours, but after four days, she presented with a skin reaction compatible with hand-foot syndrome. After discontinuation of the therapy, this reaction ceased.

CONCLUSION

Sorafenib as a new therapeutic option for patients with radioactive iodine (RAI)-resistant metastatic differentiated thyroid cancer, it is important that clinicians are fully aware of the potential adverse effects. All patients on Sorafenib therapy should be educated to recognize the first symptoms to obtaining the maximal benefit from this anti-neoplastic rescue therapy.

Immunotherapy options in metastatic renal cell cancer: where we are and where we are going

The treatment of renal cell carcinoma is rapidly changing as a result of recent evidence concerning the efficacy of biological drugs, antiangiogenetic agents and signal-transduction inhibitors. This paper will provide a critical overview of the use of immunotherapy in renal cell carcinoma and review the available data concerning the efficacy of interferons, interleukin-2 and other forms of immunological treatment, particularly allogenic transplantation and vaccines. Moreover, it will focus on the new mechanisms of regulation of the immune system with a better understanding of the interaction between host and tumor, the role of T regulatory cells, heat-shock proteins and vaccines. The mechanism of action and the results obtained in renal cell carcinoma using the new molecular targeted drugs will be examined, along with the possibility of using immunotherapy combined with the new biological agents. Future research will not only need to make every effort to optimize the use of the new molecules and to define their efficacy precisely, but also to consider how to integrate these drugs with the traditional immunotherapy.

Molecularly targeted therapy in renal cell carcinoma: where do we go from here?

The angiogenic phenotype of renal cell carcinoma results from vascular endothelial growth factor pathway activation. Several different strategies targeting various aspects of the pathway have emerged as clinically relevant therapeutics in metastatic renal cell carcinoma. Key clinical data regarding these approaches are presented in this article. Furthermore, there are several considerations as to the further development of these agents and their appropriate application in metastatic renal cell carcinoma, such as timing of therapy, choice of initial therapy, continued role of debulking nephrectomy and toxicity concerns. These issues are discussed in light of current data and strategies for further drug development are presented.

Inhibitory effects of SU5416, a selective vascular endothelial growth factor receptor tyrosine kinase inhibitor, on experimental corneal neovascularization

PURPOSE

Treatment of neovascularization in ocular diseases with vascular endothelial growth factor (VEGF) inhibition shows promising results. SU5416 is a low-molecular-weight tyrosine kinase inhibitor. It selectively inhibits the membrane-bound tyrosine kinase activity of VEGF-2 receptor (Flk-1/KDR) and blocks the intracellular signaling process. The aim of this study was to evaluate the effect of SU5416 on corneal neovascularization.

METHODS

Corneas were cauterized with silver nitrate/potassium nitrate sticks in 20 eyes of 20 BALB/C mice. In the study group (n = 10), SU5416 (25 mg/kg) dissolved in dimethyl sulfoxide was given as an intraperitoneal injection in a single daily dose for 7 days. The other group of 10 mice given intraperitoneal dimethyl sulfoxide alone served as a control group. After 7 days, corneal neovascularization was evaluated using photographs captured by fluorescein angiography. Colored photographs were taken by a biomicroscope with a digital camera. Data were expressed as mean neovascular length and mean number of new vessels for each animal. The values were computed and compared between the groups.

RESULTS

The mean burn stimulus intensities were not different between the groups. In the study group, the mean length of the vessels and the mean number of vessels were 0.49 ± 0.05 and 11.20 ± 1.69 mm, respectively. In the control group, the mean length of the vessels and the mean number of the vessels were 0.89 ± 0.11 and 17.80 ± 1.03 mm, respectively. There is a statistically significant difference in the mean length and the mean number of new vessels between the study and control groups (p < 0.001).

CONCLUSION

Selective inhibition of VEGFR-2 (Flk-1/KDR) tyrosine kinase with SU5416 was shown to have an inhibitory effect on corneal neovascularization in this animal model. VEGFR-2 (Flk-1/KDR) tyrosine kinase inhibition may represent a different pathway for treatment of the neovascularization process in ocular pathologies. Fluorescein angiography photographs of new vessels on the cornea may provide a better evaluation of neovascularization than colored images in animal models.

Contrary effects of the receptor tyrosine kinase inhibitor vandetanib on constitutive and flow-stimulated nitric oxide elaboration in humans

Vascular endothelial growth factor regulates neoplastic angiogenesis through production of endothelium-derived NO. We performed a prospective evaluation of vascular function during treatment with vandetanib, a vascular endothelial growth receptor 2 and 3 receptor tyrosine kinase inhibitor, to determine the effects of vascular endothelial growth receptor signal interruption on endothelial function in humans. Seventeen patients with stage IV breast cancer received dose-escalated vandetanib in combination with low-dose oral chemotherapy. We measured blood pressure, systemic nitrate/nitrite levels, and brachial artery vascular function. In vitro analyses of cultured endothelial cells were performed to determine the effect of vandetanib on NO production, akt(473) phosphorylation, and endothelial NO synthase protein content and membrane localization. Vandetanib treatment for 6 weeks significantly increased blood pressure, decreased resting brachial artery diameter, and decreased plasma systemic nitrate/nitrite levels compared with baseline. Flow-mediated vasodilation was preserved, and no change was noted in nitroglycerin-mediated vasodilation. In vitro, endothelial cell nitrite levels and akt(473) phosphorylation were reduced and vascular endothelial growth receptor 2 levels did not change, but endothelial NO synthase membrane concentration doubled. Vandetanib reduces constitutive NO production and increases blood pressure, yet flow-stimulated NO bioavailability was preserved. Changes in vascular function with tyrosine kinase inhibition are complex and require further study in humans.

Targeted therapy for melanoma: a primer

Melanoma is the most aggressive form of skin cancer. Unfortunately, despite recent improvements for some solid tumors, the prevalence and mortality of melanoma continue to increase. The identification of activating mutations in melanoma, combined with a growing appreciation of the different pattern of genetic changes in the anatomically defined melanoma subtypes, has become the focus of a concerted effort to translate these discoveries into personalized therapeutic approaches for this disease. This article reviews the known mutations, amplifications, and deletions in kinase signaling pathways that have been implicated in melanoma; the prevalence of these genetic events in clinicopathologically defined melanoma subtypes; and the results of clinical trials that use targeted therapy approaches to block aberrantly activated pathways resulting from these mutations. The challenges that must be overcome to achieve improved outcomes with targeted therapies in melanoma in the future are also discussed.

Emerging molecular classification in renal cell carcinoma: implications for drug development

In the past decade, progress has been made in the development of targeted therapies for advanced renal cell carcinoma (RCC). However, as multiple therapeutic choices become available to clinicians, we currently lack effective indicators that allow physicians to choose the best treatment option for specific patients. For approved targeted therapies, potential molecules that could indicate drug effectiveness in a specific tumor follow naturally from both the therapeutic mechanism and the previously elucidated tumor biology. However, in advanced RCC, the use of these molecules as biomarkers for treatment selection has shown equivocal results and requires further investigation. In addition to looking at specific molecular targets, subclassification of tumors based on their molecular characteristics may also allow stratification of patients based on therapeutic benefits, providing information for treatment selection. Furthermore, the continued development of such tumor classification schemes will hopefully uncover other molecular targets that warrant development as future RCC therapies. The use of molecular classification of patients' tumors for treatment selection will provide the opportunity to increase the effectiveness of currently available therapies for advanced RCC and to judiciously pursue promising options for future RCC therapies.

Mechanisms of resistance to antiangiogenesis therapy

Angiogenesis, the formation of new blood vessels from existing vasculature, plays an essential role in tumour growth, invasion and metastasis. Vascular endothelial growth factor (VEGF) is one of the key factors responsible for its regulation. High expression of VEGF has been observed in many cancers, and is associated with worse survival. When antiangiogenic agents are used alone they typically initially cause reduction in blood flow or vascular permeability, in many types of cancer. In some cases tumour regression occurs, mainly in renal cancer. In combination with chemotherapy, progression-free survival is often prolonged, but overall survival is not. Many tumours fail to respond initially - de novo resistance. Others develop resistance over time, with progression after a few months of treatment. The mechanisms of resistance are not well understood. The theoretical benefits of VEGF inhibitors are more likely to be realised by understanding these mechanisms and modifying therapy accordingly. This article reviews current knowledge on resistance mechanisms and the therapeutic implications.

Updates on novel therapies for metastatic renal cell carcinoma

Metastatic renal cell carcinoma (RCC) poses one of the great therapeutic challenges in oncology. RCC is predominantly refractory to treatment with traditional cytotoxic chemotherapies, and until recently management options were limited to immunotherapy or palliative care. However, in the past few years we have experienced a sea change in the treatment of advanced RCC with the introduction of targeted therapies that derive their efficacy at least in part through alterations in tumor angiogenesis. The tyrosine kinase inhibitors sunitinib, pazopanib, and sorafenib, the monoclonal antibody bevacizumab (in combination with interferon-α), and the rapamycin analogs, temsirolimus and everolimus, are now approved agents in the United States for the treatment of metastatic RCC. Efforts to expand upon these successes include developing novel antiangiogenic agents, optimizing concomitant and sequential regimens, identifying predictors of response to specific treatments, and further dissecting the underlying molecular pathogenesis of RCC to reveal novel therapeutic targets.

Sorafenib tosylate in advanced kidney cancer: past, present and future

The objective of this paper was to review the development of sorafenib tosylate in kidney cancer. The MedLine database, the Proceedings of the Annual American Society of Clinical Oncology meeting, as well as those of other key international meetings were extensively searched to identify relevant publications. Furthermore, the authors' direct experience with the drug was taken into account when commenting on the results retrieved. Sorafenib is a multikinase inhibitor that targets VEGF and PDGF receptors, other kinases, as well as the serine-threonine kinase Raf. Following early signs of activity from phase I and II studies, it has been shown to improve survival of pretreated advanced kidney cancer patients within a placebo-controlled, randomized, phase III trial, leading to its approval both in the United States and in Europe. Its activity has been subsequently confirmed in a real-world population by two expanded access programs performed globally, but not in a first-line setting; it also proved to be non-cross-resistant with two other molecularly targeted agents. Finally, its toxicity profile, which is acceptable and highly predictable, makes sorafenib appealing for combination treatments, especially with other molecularly targeted agents. Despite having been already demonstrated to be active in kidney cancer, the exact role of sorafenib in the first-line setting, in patients who have failed other molecularly targeted agents, and especially in combination with other agents, deserves further, prospective, studies.

Effect of the UK postcode lottery on survival of patients with metastatic renal cancer: an audit of outcomes in patients with metastatic renal cancer suitable for treatment with tyrosine kinase inhibitors

AIMS

To determine whether primary care trusts' agreement or refusal to fund sorafenib or sunitinib affects outcomes for patients with metastatic renal cell carcinoma.

MATERIALS AND METHODS

This retrospective audit was conducted in a tertiary referral centre for urological cancer. Requests to prescribe drugs not approved by the National Institute for Health and Clinical Excellence are recorded on a trust database. We obtained details of all requests made for sunitinib and sorafenib for patients with renal cell carcinoma since licence in 2006. Outcome measures analysed were overall survival measured from the date of request for funding and hospital resource use as measured from Payment by Results data. Known prognostic factors and the patient's Index of Multiple Deprivation score were assessed at baseline as potential confounders of survival difference.

RESULTS

Seventy-nine patients were identified. The groups were similar with respect to prognostic factors and Index of Multiple Deprivation scores. Thirty-seven and eight patients had funding approved for sunitinib and sorafenib, respectively; 21 and 13 were turned down. Seven patients who were denied funding received one or other of these drugs by self-funding treatment. Survival was longer for patients who received treatment with a drug for which they had applied for funding than for those who did not (hazards ratio 0.46; 95% confidence interval 0.21-1.01; chi(2)=3.80; 1 d.f.; P=0.05); the advantage was similar for patients receiving sunitinib (hazards ratio=0.49; 95% confidence interval 0.18-1.36; chi(2)=1.86; 1 d.f.; P=0.17) and sorafenib (hazard ratio=0.44; 95% confidence interval 0.11-1.69; chi(2)=1.58; 1 d.f.; P=0.21). Overall National Health Service resource use apart from funding for the renal cancer drugs was similar for both groups.

CONCLUSIONS

Compared with patients receiving treatment, patients denied access to sunitinib and sorafenib had substantially worse survival outcomes, despite receiving treatment from the same clinical team. Access to the new drugs did not have an effect on overall use of National Health Service resources by funded patients. Modern treatments for advanced renal cancer should be available to all National Health Service patients with the disease.

Clinical implications of hypoxia inducible factor in renal cell carcinoma

Management of renal cell carcinoma (RCC) has made considerable strides in the past decade, due in large part to identification of the von Hippel Lindau (VHL) tumor suppressor as a negative regulator of hypoxia inducible factor alpha (HIF-alpha) protein expression. Stabilization of HIF-alpha appears to be critical for renal tumorigenesis, and is observed even in VHL-independent RCC. Thus, an understanding of the pathways that regulate expression and activation of the different HIF-alpha isoforms is key to delineating the mechanism of renal transformation and for the development of novel therapeutics. A number of agents targeting HIF-alpha or its transcriptionally-regulated genes have shown promise in treatment of RCC. However, more effective treatment strategies are still needed. This report provides a directed review of recent discoveries defining the role of HIF in renal tumorigenesis and their relevance to the clinical advances in targeted therapy for advanced RCC.

VEGF kinase inhibitors: how do they cause hypertension?

Neoangiogenesis is a critical phenomenon enabling the growth and metastasis of tumors, and inhibitors of neoangiogenesis have been recently added to the armamentarium of anticancer therapies available for clinical use. Dysregulated signaling through the vascular endothelial growth factor (VEGF) pathway has been implicated as a key mediator of neoangiogenesis in tumors. Agents that block signaling through the VEGF pathway demonstrated tumor shrinkage in preclinical models and were therefore developed as anticancer therapies for use in humans. VEGF kinase inhibitors are being used in the treatment of a wide variety of cancers, and recent studies have shown that patients will likely require long-term treatment with these agents. Hypertension has emerged as a frequent side effect associated with agents that block signaling through the VEGF pathway. A thorough understanding of the mechanisms underlying hypertension is crucial to developing appropriate therapeutic strategies for treating hypertension associated with VEGF kinase inhibitors. Several recent studies have advanced our understanding of the pathophysiology of hypertension associated with VEGF kinase inhibitors and will be the subject of this review.

Metastatic renal cell cancer treatments: an indirect comparison meta-analysis

BACKGROUND

Treatment for metastatic renal cell cancer (mRCC) has advanced dramatically with understanding of the pathogenesis of the disease. New treatment options may provide improved progression-free survival (PFS). We aimed to determine the relative effectiveness of new therapies in this field.

METHODS

We conducted comprehensive searches of 11 electronic databases from inception to April 2008. We included randomized trials (RCTs) that evaluated bevacizumab, sorafenib, and sunitinib. Two reviewers independently extracted data, in duplicate. Our primary outcome was investigator-assessed PFS. We performed random-effects meta-analysis with a mixed treatment comparison analysis.

RESULTS

We included 3 bevacizumab (2 of bevacizumab plus interferon-a [IFN-a]), 2 sorafenib, 1 sunitinib, and 1 temsirolimus trials (total n = 3,957). All interventions offer advantages for PFS. Using indirect comparisons with interferon-alpha as the common comparator, we found that sunitinib was superior to both sorafenib (HR 0.58, 95% CI, 0.38-0.86, P = < 0.001) and bevacizumab + IFN-a (HR 0.75, 95% CI, 0.60-0.93, P = 0.001). Sorafenib was not statistically different from bevacizumab +IFN-a in this same indirect comparison analysis (HR 0.77, 95% CI, 0.52-1.13, P = 0.23). Using placebo as the similar comparator, we were unable to display a significant difference between sorafenib and bevacizumab alone (HR 0.81, 95% CI, 0.58-1.12, P = 0.23). Temsirolimus provided significant PFS in patients with poor prognosis (HR 0.69, 95% CI, 0.57-0.85).

CONCLUSION

New interventions for mRCC offer a favourable PFS for mRCC compared to interferon-alpha and placebo.

Clinical effect and future considerations for molecularly-targeted therapy in renal cell carcinoma

Vascular endothelial growth factor (VEGF) pathway activation leads to the angiogenic phenotype of renal cell carcinoma (RCC). Several different strategies targeting various aspects of this pathway have emerged as standard therapy in metastatic RCC. Bevacizumab, a VEGF ligand-binding antibody, sunitinib and sorafenib, small molecule inhibitors of the VEGF receptor, as well as temsirolimus, an inhibitor of mammalian target of rapamycin (mTOR) have all shown substantial clinical activity in metastatic RCC. Several relevant clinical aspects have also emerged with use of these agents such as defining resistance, measurement of response, and combination therapy.

Sorafenib in lung cancer: clinical developments and future directions

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death in the United States. Angiogenesis, primarily mediated through vascular endothelial growth factor (VEGF), is one of the key steps in tumor growth and metastasis. VEGF is now a validated target for NSCLC based on the results of the Eastern Cooperative Oncology Group trial E4599 which showed that the addition of bevacizumab, a VEGF monoclonal antibody, to cytotoxic chemotherapy improves survival compared with chemotherapy alone in patients with metastatic NSCLC. As NSCLC has complex and integrated signaling pathways, a rational approach is to target more than one of these pathways concurrently. Sorafenib, which is approved for the treatment of renal cell carcinoma, is a multitargeted signal transduction inhibitor that inhibits raf-kinases, VEGF receptor-2, platelet derived growth factor receptor-B, and c-kit. In a phase II monotherapy trial in patients with previously treated NSCLC, sorafenib demonstrated activity with a disease control rate and survival rate comparable to other small molecules. Additionally, sorafenib has shown preliminary activity in combination with chemotherapy and with epidermal growth factor receptor inhibitors. Future directions will include the development of rational combinations either with cytotoxic compounds or biologically targeted compounds and the identification of subsets of patients that might benefit from the other targets of sorafenib.

Classification of renal cell carcinoma based on expression of VEGF and VEGF receptors in both tumor cells and endothelial cells

Recent development of antiangiogenic therapy for renal cell carcinoma (RCC) has significantly improved the treatment of these often refractory tumors. However, not all patients respond to therapy and assays for predicting outcome are needed. As a first step, we analyzed a retrospective cohort of tumors and assessed the ability of VEGF and VEGF receptors (VEGF-R1, -R2 and -R3) to classify tumors. We analyzed tissue microarrays containing 330 RCCs using a novel method of automated quantitative analysis of VEGF and VEGF-R expression by fluorescent immunohistochemistry. Expression of markers was separately quantified within three tissue components: tumor cells, endothelial cells and adjacent normal epithelium. VEGF and VEGF receptors were tightly coexpressed both within tumors and within adjacent normal cells (all P-values <0.001). Tumor cell expression of VEGF-R1 and -R2 was strongly and inversely correlated with vessel area (P<0.0001). Unsupervised hierarchical clustering classified tumors by coordinated expression of VEGF and VEGF-Rs. The distribution of clear cell and papillary tumors was not significantly different between clusters. Clusters with high expression of VEGF and VEGF-Rs in the tumor cells exhibited poor survival when compared with the other clusters on uni- and multivariable analysis. VEGF and VEGF receptors exhibit a complex pattern of coordinated expression in RCC. Clustering tumors by VEGF and VEGF-R in tissue components demonstrates distinct tumor phenotypes with different outcomes, and may provide a means for determining which tumors will respond to what antiangiogenic therapies.

Sorafenib, but not sunitinib, affects function of dendritic cells and induction of primary immune responses

The tyrosine kinase inhibitors sorafenib and sunitinib are approved for the treatment of patients with malignant diseases. To analyze the possible use of these compounds in combination with immunotherapeutic approaches, we analyzed the effects of both inhibitors on the immunostimulatory capacity of human dendritic cells (DCs) and the induction of primary immune responses in vivo. Sorafenib, but not sunitinib, inhibits function of DCs, characterized by reduced secretion of cytokines and expression of CD1a, major histocompatibility complex, and costimulatory molecules in response to TLR ligands as well as by their impaired ability to migrate and stimulate T-cell responses. These inhibitory effects are mediated by inhibition of PI3 and MAP kinases and NFκB signaling. In contrast, sorafenib had no influence on the phenotype and proliferation of T cells. To analyze the effects of both TKIs on cytotoxic T-cell induction in vivo, C57BL/6 mice were pretreated with sorafenib or sunitinib and immunized with OVA257-264 peptide. Sorafenib, but not sunitinib, application significantly reduced the induction of antigen-specific T cells. Numbers of regulatory T cells were reduced in peripheral blood mononuclear cells from mice treated with sunitinib. These results indicate that sunitinib, but not sorafenib, is suitable for combination with immunotherapeutic approaches for treatment of cancer patients.

Posttranscription regulation of prostate cancer growth

Advances in the understanding of the molecular mechanisms implicated in prostate cancer progression have allowed identification of many potential therapeutic gene targets that are involved in apoptosis, growth factors, cell signaling, and the androgen receptor. A critical factor responsible for the malignant progression of prostate cancer is the abnormal expression and function of specific proteins. From the transcription of mRNA to the translation of proteins and their function, several steps can be exploited as "drugable" targets. In this article we will review some of the key molecular targets and posttranscriptional strategies that are currently being tested both preclinically and clinically as targeted therapeutic approach for prostate cancer. Most of the targets mentioned in this review involve the prostate cancer signal transduction cascade, and their functions include prosurvival, antiapoptosis, and proangiogenesis. We will focus in particular on the emerging role of the "chromatin modifiers," histone deacetylase inhibitors, not only in transcriptional gene regulation but also in posttranscriptional protein modifications as a tool for therapeutic intervention in prostate cancer.

Is cell death a critical end point for anticancer therapies or is cytostasis sufficient?

Since the discovery of conventional chemotherapy and the development of new target-based agents, the importance of cytostasis in anticancer activity has been debated. This review examines the relative importance of both cytostasis and cytotoxicity based on both preclinical data and clinical reports. Several limitations of our basic and clinical methods to evaluate cytostasis and cytotoxicity will be highlighted. Molecular mechanisms of cytostasis will be analyzed, including interference with the cell cycle as well as putative links with necrosis and autophagy. Finally, we will cite evidence that most older and newer compounds are both cytostatic and cytotoxic. The relative role of cytostasis and cytotoxicity on future drug screening and clinical development will be explored.

Surgical management of large renal tumors

In addition to an increased occurrence of small, localized, incidentally discovered renal cell carcinomas (RCCs), there has been an upward trend in the incidence of advanced renal tumors per unit of population and in disease mortality worldwide. As radical nephrectomy remains the standard of care in treating localized RCC, this manuscript focuses on surgical approaches. We defined 'large renal tumors' as those greater than 7 cm or those with venous involvement. We discuss operative strategies in both open and laparoscopic surgery as well as approaches to special circumstances, including patients with tumor thrombus and the indications for nephron-sparing surgery in patients with greater than T2 RCC. The literature pertaining to controversial areas such as preoperative renal artery embolization and the clinical utility of metastectomy and cytoreductive therapy are also reviewed. The theoretical basis and potential applications of neoadjuvant therapy for larger renal tumors is examined as well.

Cutaneous reactions related to systemic immunomodulators and targeted therapeutics

The arrival of targeted therapeutics into the oncology clinic, while enthusiastically anticipated, introduced the oncologist to dermatologic events that can pose challenging management issues. The dermatologic effects of these targeted agents appear to be more frequent than those with cytotoxic therapy and are not uniform; that is, different agents have distinct dermatologic toxicities. Interestingly, dermatologic toxicity may correlate with antitumor activity with some of these targeted agents. The correlation of rash with response and survival in particular mandates the development of effective and appropriate management strategies. The nature and challenges of the dermatologic events observed to date with epidermal growth factor receptor inhibitors, multikinase inhibitors, proteosome inhibitors, BCR-ABL tyrosine kinase inhibitors, and immunomodulatory drugs will be addressed in this review.

Novel somatic mutations of the VHL gene in an erythropoietin-producing renal carcinoma associated with secondary polycythemia and elevated circulating endothelial progenitor cells

Mutation of the VHL tumor suppressor gene is a frequent genetic event in the carcinogenesis of renal-cell carcinoma (RCC). Circulating endothelial progenitor cells (EPCs) have important role in neoangiogenesis, and mobilization of these cells is induced by various growth factors including erythropoietin (EPO). With this regard, we analyzed a patient with EPO-producing clear-cell RCC and polycythemia. DNA extraction and sequencing analysis of the VHL gene were performed from the tumor and the adjacent normal renal tissue. Isolated and cultured circulating EPCs from the blood taken with phlebotomy were characterized by flow cytometry and immunofluorescence analysis. This RCC had two novel somatic mutations of the VHL gene, p.Leu128Pro and p.Asn131Lys. Culture of blood mononuclear cells revealed a strikingly high number of endothelial cell colonies derived from EPCs (nearly 10-fold more than in controls). Elevated number of circulating EPCs seems to be related to high EPO production from RCC with novel double somatic mutation of the VHL gene in this patient.

Uncovering Pandora's vase: the growing problem of new toxicities from novel anticancer agents. The case of sorafenib and sunitinib

As newer, molecularly targeted, anticancer drugs are entering clinical practice, a wide array of previously unrecognised and ill defined side effects of these drugs are increasingly observed. Sorafenib and sunitinib are two of these novel agents, acting on tumour angiogenesis as well as on other key proliferative pathways; recently approved for the treatment of advanced kidney cancer, they may cause peculiar cutaneous, vascular and mucosal toxicities, including hand-foot skin reaction, skin rash, hypertension and GERD-like oesophagitis/gastritis. In this review, we shall deal with these poorly recognised, but sometimes extremely distressing, toxicities; pathophysiologic mechanisms will be discussed and suggestions for treatment of each toxicity will be proposed, based on the few pieces of evidence available and, especially, on our empirical experience.

TORC1 is essential for NF1-associated malignancies

Inactivating mutations in NF1 underlie the prevalent familial cancer syndrome neurofibromatosis type 1 [1]. The NF1-encoded protein is a Ras GTPase-activating protein (RasGAP) [2]. Accordingly, Ras is aberrantly activated in NF1-deficient tumors; however, it is unknown which effector pathways critically function in tumor development. Here we provide in vivo evidence that TORC1/mTOR activity is essential for tumorigenesis. Specifically, we show that the mTOR inhibitor rapamycin potently suppresses the growth of aggressive NF1-associated malignancies in a genetically engineered murine model. However, in these tumors rapamycin does not function via mechanisms generally assumed to mediate tumor suppression, including inhibition of HIF-1alpha and indirect suppression of AKT, but does suppress the mTOR target Cyclin D1 [3]. These results demonstrate that mTOR inhibitors may be an effective targeted therapy for this commonly untreatable malignancy. Moreover, they indicate that mTOR inhibitors do not suppress all tumor types via the same mechanism, suggesting that current biomarkers that rely on HIF-1alpha suppression may not be informative for all cancers. Finally, our results reveal important differences between the effects of mTOR inhibition on the microvasculature in genetically engineered versus xenograft models and indicate that the former may be required for effective preclinical screening with this class of inhibitors.

[Biologic therapy: current and future applications in oncology]

Nowadays, cancer is the first cause of death in the developed world, accounting for 94,000 yearly deaths in Spain. In recent years, advances in the field of molecular cancer biology and cancer therapy have identified a number of potential target molecules that play a critical role in the complex malignant cell transformation process. Since the approval of the first molecularly targeted drug imatinib in 2001, hundreds of novel agents are being investigated as monotherapy or in combination with chemotherapy and/or radiotherapy for the treatment of cancer of the breast, colon and rectum, lung, kidney, and head and neck, among others. Interestingly, molecularly targeted agents are becoming the new standard of care in some malignances such as renal-cell carcinoma and chronic myeloid leukemia. Future research on molecularly targeted therapies will focus on the identification of new drugs and drug targets, improved selection of tumors sensitive to these drugs, and the rational design and optimization of combination therapies.

Synergistic in vivo antitumor effect of the histone deacetylase inhibitor MS-275 in combination with interleukin 2 in a murine model of renal cell carcinoma

PURPOSE

High-dose interleukin 2 (IL-2) is a Food and Drug Administration-approved regimen for patients with metastatic renal cell carcinoma. However, the toxicity and limited clinical benefit associated with IL-2 has hampered its use. Histone deacetylase (HDAC) inhibitors have been shown to have antitumor activity in different tumor models including renal cell carcinoma, and to have immunomodulatory properties. In our study, we tested the effectiveness of combination therapy of IL-2 with the HDAC inhibitor MS-275 in a murine renal cell carcinoma (RENCA) model.

EXPERIMENTAL DESIGN

RENCA luciferase-expressing cells were implanted in the left kidney of BALB/C mice. Animals were randomly divided into four groups and treated with either vehicle, 150,000 IU of IL-2 twice daily by i.p. injections (twice weekly), 5 mg/kg of MS-275 daily by oral gavage (5 d/wk), or its combination. Treatment was started either 3 or 9 days following tumor cell injection.

RESULTS

Weekly luciferase images and tumor weight after 2 weeks of treatment showed significant tumor inhibition (>80%) in the combination treatment as compared with the IL-2 (no significant inhibition) or MS-275 (approximately 40% inhibition) treatment groups. Spontaneous lung metastases were also inhibited in the combination treatment (>90% inhibition) as compared with the single treatment group. Kaplan-Meier analyses showed statistically significant increased survival in the combination group as compared with controls and single agents. Splenocytes from mice treated with combination treatment showed greater lysis of RENCA cells than splenocytes from mice treated with single agents. The percentage of CD4(+)CD25(+) T cells and Foxp3(+) T cells (T regulatory cells) was increased or reduced, respectively, in lymph nodes from tumor-bearing animals treated with the combination of MS-275 and IL-2 as compared with control and single agents. Depletion of CD8(+) T cells abrogated the survival benefit from MS-275 + IL-2 combination.

CONCLUSIONS

These results show that the combination of IL-2 and MS-275 has a synergistic antitumor effect in vivo in an immunocompetent murine model of renal cell carcinoma. The antitumor effect was associated with the decreased number of T regulatory cells and the increased antitumor cytotoxicity by splenocytes. In conclusion, these preclinical data provide the rationale for clinical testing of the combination of IL-2 and HDAC inhibitors in the treatment of patients with renal cell carcinoma.