A phase II, open-label study of gefitinib (IRESSA) in patients with locally advanced, metastatic, or relapsed renal-cell carcinoma

Expression and Prognostic Significance of Ferroptosis-related Proteins SLC7A11 and GPX4 in Renal Cell Carcinoma

BACKGROUND

The ferroptosis inhibitory gene solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) inhibit ferroptosis in carcinoma cells. However, whether SLC7A11 and GPX4 serve as an oncogene in renal cell carcinoma (RCC) remains unclear.

METHODS

Immunohistochemistry (IHC) assays were performed to assess the expression of SLC7A11 and GPX4 in human RCC tissues. Clinical-pathological analysis was performed to explore the correlation between SLC7A11 and GPX4 expression. Kaplan-Meier survival analysis was performed to characterise the associations between protein expression and patient progressionfree survival (PFS).

RESULTS

The upregulation of SLC7A11 and GPX4 was detected by IHC in RCC tissues compared with that in normal renal tissues. Meanwhile, the expression level of SLC7A11 and GPX4 was correlated with tumour diameter and distant metastasis (P<0.05). Kaplan-Meier survival analysis indicated that patients with high SLC7A11 and GPX4 expression levels exhibited worse PFS than those with low SLC7A11 and GPX4 expression levels (P<0.05).

CONCLUSION

The upregulation of SLC7A11 and GPX4 expression was associated with poor prognosis in patients with RCC. SLC7A11 and GPX4 may serve as diagnostic and prognostic biomarkers for patients with RCC.

Altered proTGFα/cleaved TGFα ratios offer new therapeutic strategies in renal carcinoma

BACKGROUND

Treatment of renal cancer has significantly improved with the arrival to the clinic of kinase inhibitors and immunotherapies. However, the disease is still incurable in advanced stages. The fact that several approved inhibitors for kidney cancer target receptor tyrosine kinases (RTKs) suggests that these proteins play a critical role in the pathophysiology of the disease. Based on these precedents, we decided to explore whether RTKs other than those targeted by approved drugs, contribute to the development of kidney cancer.

METHODS

The activation status of 49 RTKs in 44 paired samples of normal and tumor kidney tissue was explored using antibody arrays, with validation by western blotting. Genetic and pharmacologic approaches were followed to study the biological implications of targeting the epidermal growth factor receptor (EGFR) and its ligand Transforming Growth Factor-α (TGFα).

RESULTS

Activation of the EGFR was found in a substantial number of tumors. Moreover, kidney tumors expressed elevated levels of TGFα. Down-regulation of EGFR or TGFα using RNAi or their pharmacological targeting with blocking antibodies resulted in inhibition of the proliferation of in vitro cellular models of renal cancer. Importantly, differences in the molecular forms of TGFα expressed by tumors and normal tissues were found. In fact, tumor TGFα was membrane anchored, while that expressed by normal kidney tissue was proteolytically processed.

CONCLUSIONS

The EGFR-TGFα axis plays a relevant role in the pathophysiology of kidney cancer. This study unveils a distinctive feature in renal cell carcinomas, which is the presence of membrane-anchored TGFα. That characteristic could be exploited therapeutically to act on tumors expressing transmembrane TGFα, for example, with antibody drug conjugates that could recognize the extracellular region of that protein.

Claspin overexpression is associated with high-grade histology and poor prognosis in renal cell carcinoma

Renal cell carcinoma (RCC) is one of the most common human cancers. We previously reported that claspin is a key regulator in the progression of gastric cancer, and it likely plays an important role in cancer stem cells of gastric cancer. However, the significance of claspin in RCC has not been examined. First, we analyzed the expression and distribution of claspin in 95 RCC cases by immunohistochemistry. In the nonneoplastic kidney, the staining of claspin was either weak or absent, whereas RCC tissue showed nuclear staining. In total, claspin expression was detected in 45 (47%) of 95 RCC cases. The claspin staining appeared relatively stronger in high nuclear grade RCC than in low nuclear grade RCC. Claspin-positive RCC cases were associated with higher T grade, tumor stage, nuclear grade, vein invasion, and poorer prognosis. CLSPN siRNA treatment decreased RCC cell proliferation. The levels of phosphorylated Erk and Akt were lower in CLSPN siRNA-transfected RCC cells than in control cells. In addition, claspin was coexpressed with CD44, epidermal growth factor receptor, p53, and programmed death ligand-1. These results suggest that claspin plays an important role in tumor progression in RCC and might be a prognostic marker and novel therapeutic target molecule.

Nephroprotective effect of β-sitosterol on N-diethylnitrosamine initiated and ferric nitrilotriacetate promoted acute nephrotoxicity in Wistar rats

BACKGROUND

The most abundant plant sterol β-sitosterol is widely used for treating heart diseases and chronic inflammatory conditions. The objective of the current study was to evaluate the nephroprotective effect of β-sitosterol against nephrotoxicants which were studied using renal function markers, antioxidant and lipid peroxidation status, and inflammatory markers.

METHODS

Male albino Wistar rats were randomly grouped into four: group 1 was vehicle control rats (0.1% carboxymethyl cellulose [CMC]); group 2 was rats treated with N-diethylnitrosamine (DEN) (200 mg/kg body weight [bw] i.p. on the 15th day) and ferric nitrilotriacetate (Fe-NTA) (9 mg/kg bw i.p. on 30th and 32nd days); group 3 was rats that received β-sitosterol (20 mg/kg bw in 0.1% CMC, p.o. for 32 days) 2 weeks prior to the exposure to the nephrotoxicant; and group 4 was rats that received β-sitosterol alone. The experiment was terminated after the 24 h of last dosage of Fe-NTA, and all the animals were sacrificed. The blood, liver and kidney from each group were analyzed for biochemical, molecular and histological changes.

RESULTS

All the parameters showed significant changes in DEN and Fe-NTA treated animals, whereas β-sitosterol pretreated animals' altered biochemical parameters were restored to near normal. Histopathological and immunoexpression studies on tissues also corroborate the biochemical endpoints.

CONCLUSIONS

Administration of β-sitosterol to nephrotoxicity induced rats showed significant positive changes in biochemical parameters, histopathological and immunohistochemical observations, and up-regulation of Nrf2 gene expression. From this, it was clear that β-sitosterol showed renal protective function.

Progress of molecular targeted therapies for advanced renal cell carcinoma

Vascular endothelial growth factor (VEGF) plays a crucial role in tumor angiogenesis. VEGF expression in metastatic renal cell carcinoma (mRCC) is mostly regulated by hypoxia, predominantly via the hypoxia-induced factor (HIF)/Von Hippel-Lindau (VHL) pathway. Advances in our knowledge of VEGF role in tumor angiogenesis, growth, and progression have permitted development of new approaches for the treatment of mRCC, including several agents targeting VEGF and VEGF receptors: tyrosine kinase pathway, serine/threonine kinases, α 5 β 1-integrin, deacetylase, CD70, mammalian target of rapamycin (mTOR), AKT, and phosphatidylinositol 3'-kinase (PI3K). Starting from sorafenib and sunitinib, several targeted therapies have been approved for mRCC treatment, with a long list of agents in course of evaluation, such as tivozanib, cediranib, and VEGF-Trap. Here we illustrate the main steps of tumor angiogenesis process, defining the pertinent therapeutic targets and the efficacy and toxicity profiles of these new promising agents.

Safety and feasibility of targeted agent combinations in solid tumours

The plethora of novel molecular-targeted agents (MTAs) has provided an opportunity to selectively target pathways involved in carcinogenesis and tumour progression. Combination strategies of MTAs are being used to inhibit multiple aberrant pathways in the hope of optimizing antitumour efficacy and to prevent development of resistance. While the selection of specific agents in a given combination has been based on biological considerations (including the role of the putative targets in cancer) and the interactions of the agents used in combination, there has been little exploration of the possible enhanced toxicity of combinations resulting from alterations in multiple signalling pathways in normal cell biology. Owing to the complex networks and crosstalk that govern normal and tumour cell proliferation, inhibiting multiple pathways with MTA combinations can result in unpredictable disturbances in normal physiology. This Review focuses on the main toxicities and the lack of tolerability of some common MTA combinations, particularly where evidence of enhanced toxicity compared to either agent alone is documented or there is development of unexpected toxicity. Toxicities caused by MTA combinations highlight the need to introduce new preclinical testing paradigms early in the drug development process for the assessment of chronic toxicities resulting from such combinations.

Lapatinib and renal cell carcinoma

INTRODUCTION

Major progress in treatment of renal cell carcinoma (RCC) has occurred in the past decade.

AREAS COVERED

This review reports the background on the potential implication of the EGF/EGFR pathway in RCC, the different data on EGFR positivity in RCC and results from prospective Phase II and III trials on lapatinib in RCC, along with other EGF/EGFR inhibitors.

EXPERT OPINION

Despite important progress and the real revolution of the past decade in treatment of RCC, treatment still remains palliative most of the time. To improve treatment, it is necessary to understand whether a specific population could be selected on a molecular feature of the tumor. Until there is better knowledge of the biology, further development of drugs such as lapatinib cannot be supported.

EGFR expression is linked to osteopontin and Nf-κB signaling in clear cell renal cell carcinoma

AIM AND BACKGROUND

Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase involved in many important aspects of cell biology that are related to tumorigenesis. There are opposite evidences of the role of EGFR in renal cancer and the outcome of EGFR-targeted therapies, suggesting the complexity of EGFR signaling pathways. In vitro, osteopontin (OPN) and nuclear factor kappa B (NF-κB) are thought to be involved in specific ligand-independent EGFR activation that could have a role in resistance to EGFR mAb therapy. Aim of this study was to analyze the relationship between EGFR and OPN at the protein and mRNA level, as well as their relation to NF-κB in clear cell renal cell carcinoma (CCRCC).

MATERIALS AND METHODS

Expression of EGFR, OPN, and p65 NF-κB protein was analyzed using immunohistochemistry and compared mutually in 88 CCRCC samples. Expression of EGFR and OPN mRNAs was analyzed using quantitative Real-time PCR in 22 CCRCC samples and compared mutually and with NF-κB protein expression.

RESULTS

Epidermal growth factor receptor mRNA level was higher in CCRCC samples in comparison with normal renal tissue (p = 0.012) and was associated with high OPN mRNA level, and with NF-κB activation (p < 0.001 and p = 0.045, respectively). Immunohistochemical staining showed the inverse association; high EGFR protein expression was related with low OPN and NF-κB protein expression (p < 0.001 and p = 0.047, respectively).

CONCLUSION

Epidermal growth factor receptor gene is upregulated in CRCC and associated with OPN gene expression and NF-kB signaling. The inverse relation between OPN and EGFR at the protein level could probably reflect dynamic changes that EGFR undergoes following activation.

Systemic therapy for advanced renal cell carcinoma

Renal cell carcinoma (RCC) accounts for approximately 3% of all cancers and is refractory to cytotoxic chemotherapy - immunotherapy has until recently been the standard of care for advanced disease. Randomised trials reported in the last 5 years have demonstrated that a number of agents including the monoclonal antibody, bevacizumab, and the kinase inhibitors - sorafenib sunitinib, temsirolimus and everolimus - are active in advanced RCC. Bevacizumab is directed against the vascular endothelial growth factor (VEGF), a key mediator of angiogenesis, whilst sorafenib and sunitinib inhibit a number of targets including the VEGF and platelet-derived growth factor (PDGFR) receptor tyrosine kinases. Temsirolimus and everolimus inhibit the intracellular mammalian target of rapamycin (mTOR) kinase. Sunitinib and temsirolimus have demonstrated efficacy in comparison with immunotherapy in the first-line setting in patients with favourable and poor prognosis advanced disease respectively. In the second-line setting, everolimus has shown benefit over placebo in patients who progress following treatment with a VEGF receptor tyrosine kinase inhibitor and sorafenib has demonstrated efficacy in comparison with placebo in patients with immunotherapy-refractory disease. We review here recent clinical trial data and discuss future developments in the systemic treatment of RCC including combination and sequential therapy, adjuvant therapy, the role of biomarkers and the prospects for the development of rational mechanism-directed therapy in this disease.

A phase II trial of gefitinib and pegylated IFNα in previously treated renal cell carcinoma

BACKGROUND

This study was conducted to evaluate the efficacy of the epidermal growth factor receptor tyrosine kinase inhibitor gefitinib with pegylated-IFNα (PEG-IFNα) in patients with advanced renal cell carcinoma.

METHODS

Progression-free survival (PFS) rate at 6 months >50% was considered promising for further evaluation. Patients with unresectable or metastatic disease, unlimited prior therapies, and adequate performance status and end-organ function were eligible. PEG-IFNα was dosed subcutaneously once weekly (initially 6 μg/kg/week, later reduced to 4 μg/kg/week) for 12 weeks. Gefitinib was given 250 mg orally once daily until progression or intolerance.

RESULTS

Twenty-one patients were accrued. Fourteen patients had a prior nephrectomy, and twelve had prior systemic therapy. The 6-month PFS was 29% (95%CI 15-56%). Best responses by RECIST criteria: complete, partial (1, plus 3 unconfirmed) stable (Uhlman et al. Clin Cancer Res 1:913-920, 1995), and progression (Sirotnak et al. Clin Cancer Res 6:4885-4892, 2000). Response duration: complete response (35+ months) and partial response (2, 3, 3, 37 months). Median PFS and overall survival were 5.3 (95%CI 3-10.1) and 13.6 (95%CI 10.3-NA) months, respectively. Most common toxicities included myelosuppression, rash, and nausea.

CONCLUSIONS

Although generally well tolerated, gefitinib plus PEG-IFNα did not meet the pre-specified 6-month PFS rate >50%. Further evaluation of similar regimens would require appropriate molecular selection of subjects most likely to benefit. Thus, preclinical studies to determine candidate predictive markers for this combination are warranted.

Phase I/II trial of sunitinib plus gefitinib in patients with metastatic renal cell carcinoma

OBJECTIVES

Sunitinib is an oral, multitargeted tyrosine kinase inhibitor of vascular endothelial growth factor and platelet-derived growth factor receptors with proven clinical benefit in patients with metastatic renal cell carcinoma (RCC). This phase I/II study investigated sunitinib in combination with an epidermal growth factor receptor inhibitor, gefitinib, in patients with metastatic RCC.

METHODS

In phase I, patients received sunitinib 37.5 or 50 mg in 6-week cycles (4 weeks on treatment, 2 off) plus gefitinib 250 mg, both once daily, to determine the sunitinib maximum tolerated dose (MTD). Pharmacokinetics was assessed for both drugs. In phase II, patients received sunitinib MTD plus gefitinib to evaluate the safety and antitumor activity of this combination.

RESULTS

Forty-two patients were enrolled: 11 in phase I, and 31 in phase II. In phase I, 2 dose-limiting toxicities were observed with sunitinib 50 mg (grade 2 left ventricular ejection fraction decline and grade 3 fatigue), and 37.5 mg was declared the MTD. Thirteen patients treated at the MTD achieved a partial response (objective response rate: 37%; 95% confidence interval, 22-55) and 12 (34%) had stable disease. Median progression-free survival was 11 months (95% confidence interval, 6-17). The most commonly reported grade 3/4 treatment-related adverse event was diarrhea (14%), the only grade 3/4 adverse event to occur in >2 patients. Pharmacokinetic analyses did not indicate any drug-drug interactions.

CONCLUSIONS

In metastatic RCC, sunitinib plus gefitinib demonstrated comparable efficacy to sunitinib monotherapy with an acceptable safety profile. Dosing, pharmacokinetic profile, and safety support study of sunitinib plus an epidermal growth factor receptor inhibitor in other tumor types.

Safety and efficacy of the combination of erlotinib and sirolimus for the treatment of metastatic renal cell carcinoma after failure of sunitinib or sorafenib

BACKGROUND

The mammalian target of rapamycin (mTOR) is an important therapeutic target in the treatment of renal cell carcinoma (RCC). Pre-clinical data indicate that the combined inhibition of both the epidermal growth factor receptor and mTOR results in enhanced anticancer activity.

METHODS

All patients had metastatic RCC with progression after treatment with sunitinib and/or sorafenib. Treatment consisted of erlotinib 150 mg orally once a day starting on day 1 and sirolimus 6 mg orally on day 8 followed by 2 mg daily, adjusted according to blood levels.

RESULTS

A total of 25 patients were enrolled between July 2006 and March 2008. The median progression-free survival (PFS) was 12 weeks (95% CI 5.9-18.1) and median overall survival (OS) 40 weeks (95% CI 0-85.7). No confirmed complete or partial responses were observed, but stable disease >6 months was noted in 21.8% (95% CI 4.9-38.6) of patients. The most common adverse events were rash and diarrhoea. There was no correlation between erlotinib, OSI-420 (days 8 and 15) or sirolimus (days 15 and 29) blood levels and PFS or OS.

CONCLUSIONS

The combination of sirolimus and erlotinib for RCC failed to demonstrate an advantage over available single-agent therapy in the second-line setting.

Update on vaccine development for renal cell cancer

Renal cell carcinoma (RCC) remains a significant health concern that frequently presents as metastatic disease at the time of initial diagnosis. Current first-line therapeutics for the advanced-stage RCC include antiangiogenic drugs that have yielded high rates of objective clinical response; however, these tend to be transient in nature, with many patients becoming refractory to chronic treatment with these agents. Adjuvant immunotherapies remain viable candidates to sustain disease-free and overall patient survival. In particular, vaccines designed to optimize the activation, maintenance, and recruitment of specific immunity within or into the tumor site continue to evolve. Based on the integration of increasingly refined immunomonitoring systems in both translational models and clinical trials, allowing for the improved understanding of treatment mechanism(s) of action, further refined (combinational) vaccine protocols are currently being developed and evaluated. This review provides a brief history of RCC vaccine development, discusses the successes and limitations in such approaches, and provides a rationale for developing combinational vaccine approaches that may provide improved clinical benefits to patients with RCC.

Cancer-associated fibroblasts derived from EGFR-TKI-resistant tumors reverse EGFR pathway inhibition by EGFR-TKIs

Epidermal growth factor receptor (EGFR) plays a critical role in oncogenesis, which makes it an attractive target for pharmacologic inhibition. Yet, EGFR inhibition with tyrosine kinase inhibitors (TKI) does not result in a measurable and sustainable clinical benefit in a vast majority of tumors. This emphasizes the need for further investigations into resistance mechanisms against EGFR-TKIs. We previously reported the generation of an in vivo adenocarcinoma model of EGFR-TKI-acquired resistance that was devoid of the known mechanisms of resistance. Using this same xenograft model, we now show that the tumor stroma plays an important role in limiting responsiveness to EGFR-TKIs. EGFR-TKI-resistant tumors display increased surface expression of CD44(hi)/CD24(lo) and markers of epithelial to mesenchymal transition (EMT), SNAI1, and N-cadherin. An in vivo green fluorescent protein-tagging approach reveals that the tumor stroma of the EGFR-TKI-resistant tumors is distinct in that 24% of its cancer-associated fibroblast (CAF) population is composed of EMT-derived tumor cells that represent the in vivo escape from EGFR-TKIs. We further show that EMT subpopulation-harboring CAFs isolated from the EGFR-TKI-resistant tumors are tumorigenic and express the biomarker of gefitinib resistance, epithelial membrane protein-1. Finally, we provide evidence that paracrine factors secreted from the EGFR-TKI-resistant CAFs mitigate the EGFR-TKI-mediated blockade of pEGFR and pMAPK in cocultured tumor cells, regardless of their EGFR mutational status. This is the first demonstration that the tumor stroma is modified with acquisition of EGFR-TKI resistance and that it further contributes in promoting drug resistance.

Small-molecule inhibitors of the human epidermal receptor family

BACKGROUND

Small molecule inhibitors of human epidermal receptors (HER) have become an integral part of the armamentarium available to the medical oncologist in the treatment of solid tumor malignancies. At present, there are two small-molecule inhibitors (erlotinib and lapatinib) approved by the FDA in the USA, and a third inhibitor, gefitinib, is approved in other countries.

OBJECTIVE

To summarize the current standards of care for these new agents in solid tumors, and to discuss ongoing clinical trials; to review the known mechanisms of action of these inhibitors as well as to discuss both the known predictive markers for response and likely mechanisms of resistance.

METHODS

We reviewed key presentations and recent publications on small-molecule inhibitors targeting the HER family in solid tumors.

CONCLUSIONS

Recent data have highlighted the importance of mutations and amplifications of receptors within the HER family. Amplification of HER2 often translates into responses in anti-HER2 therapy. Mutations either enhance sensitivity or confer resistance to small-molecule inhibitors. Other mechanisms of resistance are being elucidated which should lead to the ability to predict both responses and resistance to HER family inhibitors and should translate into improvements in patient care.

Phase II study of erlotinib in patients with locally advanced or metastatic papillary histology renal cell cancer: SWOG S0317

PURPOSE

Patients with advanced papillary renal cell cancer (pRCC) have poor survival after systemic therapy; the reported median survival time is 7 to 17 months. In this trial, we evaluated the efficacy of erlotinib, an oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor in patients with advanced pRCC, a tumor type associated with wild-type von Hippel Lindau gene.

PATIENTS AND METHODS

Patients with histologically confirmed, advanced, or metastatic pRCC were treated with erlotinib 150 mg orally once daily. A RECIST (Response Evaluation Criteria in Solid Tumors) response rate (RR) of > or = 20% was considered a promising outcome. Secondary end points included overall survival and 6-month probability of treatment failure.

RESULTS

Of 52 patients registered, 45 were evaluable. The overall RR was 11% (five of 45 patients; 95% CI, 3% to 24%), and the disease control rate was 64% (ie five partial response and 24 stable disease). The median overall survival time was 27 months (95% CI, 13 to 36 months). Probability of freedom from treatment failure at 6 months was 29% (95% CI, 17% to 42%). There was one grade 5 adverse event (AE) of pneumonitis, one grade 4 thrombosis, and nine other grade 3 AEs.

CONCLUSION

Although the RECIST RR of 11% did not exceed prespecified estimates for additional study, single-agent erlotinib yielded disease control and survival outcomes of interest with an expected toxicity profile. The design of future trials of the EGFR axis in pRCC should be based on preclinical or molecular data that define appropriate patient subgroups, new drug combinations, or potentially more active alternative schedules.

Combining the receptor tyrosine kinase inhibitor AEE788 and the mammalian target of rapamycin (mTOR) inhibitor RAD001 strongly inhibits adhesion and growth of renal cell carcinoma cells

BACKGROUND

Treatment options for metastatic renal cell carcinoma (RCC) are limited due to resistance to chemo- and radiotherapy. The development of small-molecule multikinase inhibitors has now opened novel treatment options. We evaluated the influence of the receptor tyrosine kinase inhibitor AEE788, applied alone or combined with the mammalian target of rapamycin (mTOR) inhibitor RAD001, on RCC cell adhesion and proliferation in vitro.

METHODS

RCC cell lines Caki-1, KTC-26 or A498 were treated with various concentrations of RAD001 or AEE788 and tumor cell proliferation, tumor cell adhesion to vascular endothelial cells or to immobilized extracellular matrix proteins (laminin, collagen, fibronectin) evaluated. The anti-tumoral potential of RAD001 combined with AEE788 was also investigated. Both, asynchronous and synchronized cell cultures were used to subsequently analyze drug induced cell cycle manipulation. Analysis of cell cycle regulating proteins was done by western blotting.

RESULTS

RAD001 or AEE788 reduced adhesion of RCC cell lines to vascular endothelium and diminished RCC cell binding to immobilized laminin or collagen. Both drugs blocked RCC cell growth, impaired cell cycle progression and altered the expression level of the cell cycle regulating proteins cdk2, cdk4, cyclin D1, cyclin E and p27. The combination of AEE788 and RAD001 resulted in more pronounced RCC growth inhibition, greater rates of G0/G1 cells and lower rates of S-phase cells than either agent alone. Cell cycle proteins were much more strongly altered when both drugs were used in combination than with single drug application. The synergistic effects were observed in an asynchronous cell culture model, but were more pronounced in synchronous RCC cell cultures.

CONCLUSION

Potent anti-tumoral activitites of the multikinase inhibitors AEE788 or RAD001 have been demonstrated. Most importantly, the simultaneous use of both AEE788 and RAD001 offered a distinct combinatorial benefit and thus may provide a therapeutic advantage over either agent employed as a monotherapy for RCC treatment.

Renal involvement in tuberous sclerosis complex and von Hippel-Lindau disease: shared disease mechanisms?

Tuberous sclerosis complex and von Hippel-Lindau disease are distinct autosomal dominant tumor suppressor syndromes that can exhibit similar renal phenotypes and seem to share some signaling pathway components. Similarities exist in the current clinical management of, and the newly identified potential therapeutic approaches for, these conditions. This Review summarizes the pathophysiologic and therapeutic overlap between tuberous sclerosis complex and von Hippel-Lindau disease and highlights the results of recent drug trials in these settings.

High incidence of oral dysesthesias on a trial of gefitinib, Paclitaxel, and concurrent external beam radiation for locally advanced head and neck cancers

OBJECTIVES

To report a high incidence of oral mucosal dysesthesia occurring in patients on a pilot study of the epidermal growth factor receptor tyrosine kinase inhibitor gefitinib (Iressa) in combination with paclitaxel (Taxol) and external beam radiation therapy for the treatment of locally advanced squamous cell carcinoma of the head and neck.

METHODS

Nine patients were enrolled on a pilot phase I trial of oral gefitinib 250 mg/d with 6 weekly doses of paclitaxel (36 or 45 mg/m) and concurrent radiation therapy [66-76 Gray (Gy)]. All had stage III/IVA-B squamous cell carcinoma of the head and neck. Patients were evaluated twice weekly by physicians and daily by nursing for adverse events.

RESULTS

Six of 9 patients (67%) developed a grade 3 "burning" quality oral dysesthesia. These patients received at least 50 Gy (range 50-70 Gy) to the oral tongue. The patients without grade 3 oral dysesthesia received less than 50 Gy radiation to the oral tongue. The oral dysesthesia was exacerbated by the ingestion of neutral pH liquids such as water. Of the 6 patients, all eventually developed common toxicity criteria grade 3/4 mucositis; however, symptoms continued after resolution of the mucositis. Gabapentin (Neurontin) was administered to 2 patients as a treatment for painful mucosal neuropathy. Both patients had near resolution of symptoms despite the evolution of oral mucositis.

CONCLUSIONS

Development of "burning"-type oral dysesthesia occurred in patients treated with the combination of gefitinib, paclitaxel, and external beam radiation of the oral tongue. This dysesthesia was improved by the use of gabapentin.

Interferon-alpha in combination with either imatinib (Gleevec) or gefitinib (Iressa) in metastatic renal cell carcinoma: a phase II trial

Treatments for metastatic renal cell carcinoma (MRCC) are limited. RCCs frequently overexpress epithelial growth factor receptor and express c-Kit and platelet-derived growth factor receptor-beta. Combination of interferon with tyrosine kinase inhibitors of epithelial growth factor receptor [gefitinib (Iressa)] or c-Kit and platelet-derived growth factor receptor-beta [imatinib (Gleevec)] was evaluated for efficacy and safety. Patients with MRCC received 12-week cycles of interferon [3 million units (MU) subcutaneously thrice in week 1 and 6 MU thrice weekly thereafter] and either gefitinib (500 mg daily) or imatinib (600 mg daily). The gefitinib/imatinib dose was reduced as needed owing to toxicity. The primary endpoint was objective tumor response. Secondary endpoints were time to tumor progression, overall survival, and safety. Seventeen patients were enrolled. Most had clear cell [36% (6/17)] or papillary [36% (6/17)] tumors. Most (n=14) were treated on the gefitinib arm, including two patients who crossed over from the imatinib arm after experiencing disease progression. Objective tumor responses were evaluable in 14 patients (82%). Of these 14, partial responses occurred in three (21%), stable disease in seven (50%), and progressive disease in four (29%). The most frequent treatment-related adverse events were skin rash, flu-like symptoms, and fatigue (both treatment arms); diarrhea (gefitinib arm only); and thrombocytopenia and leukopenia (imatinib arm only). Median time to tumor progression (range) for patients on the gefitinib arm only was 4.27 (1.13-15.97) months and median overall survival (range) was 11.42+ (1.13-29.07+) months. Combination of gefitinib with interferon safely delays progression of refractory MRCC. Further studies in this setting are warranted.

Lapatinib versus hormone therapy in patients with advanced renal cell carcinoma: a randomized phase III clinical trial

PURPOSE

Lapatinib is an orally reversible inhibitor of epidermal growth factor receptor (EGFR)/human epidermal growth factor receptor 2 (HER-2) tyrosine kinases with demonstrated activity in patients with HER-2-positive breast cancer. In the current phase III open-label trial, lapatinib was compared with hormone therapy (HT) in patients with advanced renal cell carcinoma (RCC) that express EGFR and/or HER-2.

PATIENTS AND METHODS

Patients with advanced RCC who had experienced disease progression through first-line cytokine therapy--stratified by Karnofsky performance status and number of metastatic sites--were randomly assigned to lapatinib 1,250 mg daily or HT. The primary end point was time to progression (TTP); secondary end points included overall survival (OS), safety, and biomarker analyses.

RESULTS

Four hundred sixteen patients were enrolled onto the study. Median TTP was 15.3 weeks for lapatinib versus 15.4 weeks for HT (hazard ratio [HR] = 0.94; P = .60), and median OS was 46.9 weeks for lapatinib versus 43.1 weeks for HT (HR = 0.88; P = .29). In a biomarker analysis of patients with EGFR-overexpressed tumors (3+ by immunohistochemistry [IHC]; n = 241) median TTP was 15.1 weeks for lapatinib versus 10.9 weeks for HT (HR = 0.76; P = .06), and median OS was 46.0 weeks for lapatinib versus 37.9 weeks for HT (HR = 0.69; P = .02). These results were confirmed by Cox regression analysis. No unexpected toxicities were observed; the most commonly reported drug-related adverse events (all grades) for lapatinib were rash (44%) and diarrhea (40%).

CONCLUSION

Lapatinib was well tolerated with equivalent overall efficacy to HT in advanced RCC patients who had experienced disease progression while receiving cytokines, and the study supports that lapatinib prolonged OS relative to HT in patients with 3+ EGFR status determined by IHC.

EGFR targeting of solid tumors

BACKGROUND

Recent clinical trials suggest that epidermal growth factor receptor (EGFR)-targeted agents could benefit many patients with cancer.

METHODS

We review the current status of several EGFR-targeted therapies in cancer patients and address the efficacy of theses drugs as monotherapy or in combination with other drugs and/or treatments.

RESULTS

Cetuximab is the most widely studied anti-EGFR monoclonal antibody. Other monoclonal antibody agents under investigation are panitumumab, matuzumab, MDX-447, nimutozumab, and mAb806. Extensive research has also evaluated the efficacy of EGFR tyrosine kinase inhibitors such as erlotinib, gefitinib, EKB-569, lapatinib (GW572016), PKI-166, and canertinib (CI-1033). All of these agents have been studied for the treatment of colorectal, lung, breast, pancreatic, renal, head and neck, gynecologic, and prostate cancer. Currently, cetuximab and panitumumab are FDA approved for the treatment of metastatic colorectal cancer. Additionally, cetuximab is approved for head and neck cancer. Erlotinib is FDA approved for advanced/metastatic lung cancer. Erlotinib in combination with gemcitabine is approved for advanced/metastatic pancreatic cancer treatment.

CONCLUSIONS

EGFR-targeted agents have already shown utility in different scenarios. Researchers are continuously investigating additional cancer types and combined treatment modalities that could also benefit from the use of EGFR-targeted agents. Careful patient selection through the identification of specific biologic markers, such as gene expression, genomic polymorphism, and posttranslational modifications of EGFR downstream effectors, most likely will contribute to the successful use of these agents.

Randomized Phase II Study of Erlotinib Combined With Bevacizumab Compared With Bevacizumab Alone in Metastatic Renal Cell Cancer

Purpose

Bevacizumab (Bev) has clinical activity in advanced renal cell carcinoma (RCC), and, when combined with erlotinib (Erl), has shown encouraging objective response rate (ORR) and progression-free survival (PFS). We performed a phase II, randomized, double-blind, multicenter, placebo-controlled trial to assess whether Erl provides additional clinical benefit with regard to PFS and ORR when combined with Bev in first-line treatment of metastatic RCC.

Patients and Methods

One hundred four patients received intravenous Bev (10 mg/kg) every 2 weeks in combination with oral Erl (150 mg) or placebo daily. Patients were treated until progression or toxicity.

Results

A landmark analysis was performed 9 months after enrollment was completed (median follow-up, 9.8 months). Sixty-five patients had discontinued therapy; time to study discontinuation did not differ between the two treatment groups. The median PFS was 9.9 months (Bev + Erl [B+E]) versus 8.5 months (Bev; hazard ratio = 0.86; 95% CI, 0.5 to 1.49; P = .58). ORR (complete plus partial) was 14% (B+E) versus 13% (Bev). One complete response occurred in the B+E group. Median survival was 20 months for B+E but not reached for Bev. The most common grade 3/4 adverse events (> 5% of patients) were hypertension, rash, proteinuria, diarrhea, and hemorrhage. One treatment-related death occurred on study (GI perforation, B+E group).

Conclusion

The addition of Erl to Bev was well tolerated, but did not provide additional clinical benefit compared with Bev alone. Bev has encouraging clinical activity for previously untreated metastatic RCC patients.

Mechanisms of egfr gene transcription modulation: relationship to cancer risk and therapy response

The epidermal growth factor receptor (EGFR) plays a crucial role in growth, differentiation, and motility of normal as well as cancer cells. For predictive cancer diagnostics and therapeutic targeting of EGFR, it is important to know how the expression level of EGFR is controlled and related to receptor signaling. A novel transcriptional regulation mechanism has been described that depends on the length of a CA repeat in intron 1 [CA simple sequence repeat 1 (CA SSR I)] of the EGFR gene. Thereby, the number of CA repeats is inversely correlated to pre-mRNA synthesis. Indirect evidence for the importance of this mechanism includes the preferential occurrence of amplifications in cancer tissue harboring short CA repeats in this sequence and the discovery of distinct alleles in young breast cancer patients with a family history of the disease and in Japanese breast cancer patients. It can be postulated that the length of the CA repeat influences DNA bendability and, in consequence, the binding of repressor proteins. In summary, it seems that the CA SSR I represents an inherited variable for response to anti-EGFR therapies that could be determined before therapy. Moreover, the potential for synergistic effects with other polymorphism [e.g., EGFR R497K (HER-1 497K) and CCND1 A870G] leading to a simultaneous increase of EGFR signaling activity and expression should be investigated. From a practical perspective, assessment of the CA SSR I number of CA dinucleotide repeats as a predictor for clinical outcome is very attractive because it is a constant feature that does not change over time and can be easily measured in normal and cancer tissues (blood cells, skin, and tumor biopsies) in an assay that is technically simple, objective, and even quantitative.

Small molecule tyrosine kinase inhibitors in the treatment of solid tumors: an update of recent developments

Small molecule tyrosine kinase inhibitors (TKIs) are developed to block intracellular signaling pathways in tumor cells, leading to deregulation of key cell functions such as proliferation and differentiation. Over 25 years ago, tyrosine kinases were found to function as oncogenes in animal carcinogenesis; however, only recently TKIs were introduced as anti cancer drugs in human cancer treatment. Tyrosine kinase inhibitors have numerous good qualities. First, in many tumor types they tend to stabilize tumor progression and may create a chronic disease state which is no longer immediately life threatening. Second, side effects are minimal when compared to conventional chemotherapeutic agents. Third, synergistic effects are seen in vitro when TKIs are combined with radiotherapy and/or conventional chemotherapeutic agents. In this article, we will give an update of the tyrosine kinase inhibitors that are currently registered for use or in an advanced stage of development, and we will discuss the future role of TKIs in the treatment of solid tumors. The following TKIs are reviewed: Imatinib (Gleevec/Glivec), Gefitinib (Iressa), Erlotinib (OSI-774, Tarceva), Lapatinib (GW-572016, Tykerb), Canertinib (CI-1033), Sunitinib (SU 11248, Sutent), Zactima (ZD6474), Vatalanib (PTK787/ZK 222584), Sorafenib (Bay 43-9006, Nexavar), and Leflunomide (SU101, Arava).

Molecular biology of renal cell carcinoma

Recent developments in molecular biology have lead to an increased understanding of the events involved in renal cell carcinoma (RCC) carcinogenesis. In this field, basic molecular pathways important to oncogenic transformation secondary to Von Hippel-Lindau (VHL) tumor suppression gene inactivation, associated to clear-cell RCC, have been elucidated. Loss of function of VHL results in the high-expression of pro-angiogenic growth factors, such as vascular endothelial growth factor (VEGF) and platelet derived growth factor (PDGF). New therapies against specific targets in RCC have demonstrated significant clinical activity in patients. These therapeutic approaches are based on the VEGF inhibition by using anti-VEGF monoclonal antibodies (bevacizumab) or multi-kinase inhibitors, that also target PDGF and c-kit tyrosine kinases (sorafenib, sunitinib); or by the inhibition of the mammalian target of rapamycin (mTOR) pathway (temsirolimus). This article reviews current knowledge of molecular pathogenesis of inherited and sporadic RCC.

Systemische Therapie des metastasierten Nierenzellkarzinoms

Cytokine-based immunotherapy was the only viable option in metastatic, nonresectable renal cell carcinoma (RCC) for many years. Systemic immunotherapy has become increasingly established as a standard therapy during the last 15 years. In this context, interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) turned out to be the most effective single agents in RCC. Subsequently, the approved subcutaneous application of these compounds was the preferred administration route in Germany. Response rates with cytokine combination therapy were almost similar to those of more aggressive concepts using additional chemotherapeutic agents.Currently, new compounds targeting specific signaling pathways are readily available and have passed clinical testing. Such small molecules like tyrosine kinase inhibitors, monoclonal antibodies, or the mTOR inhibitor CCI-779 may dramatically change the established concepts of systemic RCC treatment. This paper gives an overview of established, current, and evolving concepts of systemic therapy in RCC.

Current status and perspective of antiangiogenic therapy for cancer: urinary cancer

Angiogenesis is considered a prerequisite for solid tumor growth. Antiangiogenic therapy reduces tumor size and extends host survival in a number of preclinical animal models. However, in humans antiangiogenic therapy is a poor promoter of tumor regression and has shown minimal effect on patient survival. In urinary cancers, such as renal cell cancer, prostate cancer, and bladder cancer, advanced refractory disease is a good candidate for antiangiogenic therapy because of its resistance to ordinary chemotherapy, radiotherapy, and hormonal therapy. Unique characteristics of molecular mechanisms underlie the induction of angiogenesis in urinary cancers. In this review, we summarize these unique mechanisms and review the results of clinical trials of antiangiogenic therapy for these cancers, discussing prospects and problems relating to antiangiogenic therapy.

Genomics of renal cell cancer — Does it provide breakthrough?

It is a strong hope that the more we characterize the pathways in an individual tumor, the better we will be able to evaluate the response to a specific therapy. Different array technologies could be powerful tools to achieve this goal, i.e. selecting patients on the basis of the genomic and/or proteomic profiles who would really benefit from the target-designed therapy. Genomic analysis of RCC accumulated ample of data which now can be exploited in clinical management of a previously almost uncontrollable disease. Beside the previously identified genetic abnormalities (VHL, MET, EGFR), CAIX seems to be a novel molecular marker of RCC. Array studies also outlined a small set of tumor markers, vimentin, galectin-3, CD74 and parvalbumin, which can define the individual histologic subtypes of RCC. We are at the beginning to take advantage of the genomic results. Some new approaches will interfere with the progression of RCC (anti-VEGF, anti-VEGFR or anti-EGFR therapies). Further novel molecular targets are available, such as HIF, HSP90 or the IFN-regulated genes, which can be used to the fine-tuning of RCC therapy.