Single nucleotide polymorphism associations with response and toxic effects in patients with advanced renal-cell carcinoma treated with first-line sunitinib: a multicentre, observational, prospective study

Effects of VEGF and VEGFR polymorphisms on the outcome of patients with metastatic renal cell carcinoma treated with sunitinib: a systematic review and meta-analysis

To summarize and clarify the association between vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor (VEGFR) polymorphisms and the outcome in patients with metastatic renal cell carcinoma (mRCC) treated with sunitinib. A total of 8 studies including 900 patients were analyzed in this systematic review after screening the database of PubMed, EMBASE and Web of Science. Hazard ratios (HRs) with 95% confidence interval (CI) were used to evaluate the strength of the association. VEGFR1 rs9582036 AA/AC carriers and rs9554320 CC/AC carriers had more favorable overall survival (OS) in patients with mRCC treated with sunitinib (n = 3), but not in progression-free survival (PFS). In addition, VEGFA rs2010963 was associated with poorer PFS of mRCC (n = 1). VEGFA rs699947 was significant in predicting PFS by univariate analysis, but showed no statistical significance in OS (n = 1). VEGFR2 rs1870377 was verified to be associated with sunitinib OS (n = 1). Furthermore, patients with VEGFR3 rs307826 and rs307821 had shorter PFS and OS during sunitinib therapy (n = 2, respectively). Our results suggested that VEGF and VEGFR polymorphisms were associated with outcomes in sunitinib treated mRCC patients, especially VEGFR1 polymorphisms. However, considering the limited study numbers, its clinical application in sunitinib treated mRCC still needs further confirmation.

Population Modeling Integrating Pharmacokinetics, Pharmacodynamics, Pharmacogenetics, and Clinical Outcome in Patients With Sunitinib-Treated Cancer

The tyrosine kinase inhibitor sunitinib is used as first‐line therapy in patients with metastasized renal cell carcinoma (mRCC), given in fixed‐dose regimens despite its high variability in pharmacokinetics (PKs). Interindividual variability of drug exposure may be responsible for differences in response. Therefore, dosing strategies based on pharmacokinetic/pharmacodynamic (PK/PD) models may be useful to optimize treatment. Plasma concentrations of sunitinib, its active metabolite SU12662, and the soluble vascular endothelial growth factor receptors sVEGFR‐2 and sVEGFR‐3, were measured in 26 patients with mRCC within the EuroTARGET project and 21 patients with metastasized colorectal cancer (mCRC) from the C‐II‐005 study. Based on these observations, PK/PD models with potential influence of genetic predictors were developed and linked to time‐to‐event (TTE) models. Baseline sVEGFR‐2 levels were associated with clinical outcome in patients with mRCC, whereas active drug PKs seemed to be more predictive in patients with mCRC. The models provide the basis of PK/PD‐guided strategies for the individualization of anti‐angiogenic therapies.

Worldwide Distribution of Cytochrome P450 Alleles: A Meta-analysis of Population-scale Sequencing Projects

Genetic polymorphisms in cytochrome P450 (CYP) genes can result in altered metabolic activity toward a plethora of clinically important medications. Thus, single nucleotide variants and copy number variations in CYP genes are major determinants of drug pharmacokinetics and toxicity and constitute pharmacogenetic biomarkers for drug dosing, efficacy, and safety. Strikingly, the distribution of CYP alleles differs considerably between populations with important implications for personalized drug therapy and healthcare programs. To provide a global distribution map of CYP alleles with clinical importance, we integrated whole‐genome and exome sequencing data from 56,945 unrelated individuals of five major human populations. By combining this dataset with population‐specific linkage information, we derive the frequencies of 176 CYP haplotypes, providing an extensive resource for major genetic determinants of drug metabolism. Furthermore, we aggregated this dataset into spectra of predicted functional variability in the respective populations and discuss the implications for population‐adjusted pharmacological treatment strategies.

Novel potential predictive markers of sunitinib outcomes in long-term responders versus primary refractory patients with metastatic clear-cell renal cell carcinoma

BACKGROUND

Several potential predictive markers of efficacy of targeted agents in patients with metastatic renal cell carcinoma (mRCC) have been identified. Interindividual heterogeneity warrants further investigation.

PATIENTS AND METHODS

Multicenter, observational, retrospective study in patients with clear-cell mRCC treated with sunitinib. Patients were classified in two groups: long-term responders (LR) (progression-free survival (PFS)≥22 months and at least stable disease), and primary refractory (PR) (progressive disease within 3-months of sunitinib onset). Objectives were to compare baseline clinical factors in both populations and to correlate tumor expression of selected signaling pathways components with sunitinib PFS.

RESULTS

123 patients were analyzed (97 LR, 26 PR). In the LR cohort, overall response rate was 79% and median duration of best response was 30 months. Median PFS and overall survival were 43.2 (95% confidence intervals[CI]:37.2-49.3) and 63.5 months (95%CI:55.1-71.9), respectively. At baseline PR patients had a significantly lower proportion of nephrectomies, higher lactate dehydrogenase and platelets levels, lower hemoglobin, shorter time to and higher presence of metastases, and increased Fuhrman grade. Higher levels of HEYL, HEY and HES1 were observed in LR, although only HEYL discriminated populations significantly (AUC[ROC]=0.704; cut-off=34.85). Increased levels of hsa-miR-27b, hsa-miR-23b and hsa-miR-628-5p were also associated with prolonged survival. No statistical significant associations between hsa-miR-23b or hsa-miR-27b and the expression of c-Met were found.

CONCLUSIONS

Certain mRCC patients treated with sunitinib achieve extremely long-term responses. Favorable baseline hematology values and longer time to metastasis may predict longer PFS. HEYL, hsa-miR-27b, hsa-miR-23b and hsa-miR-628-5p could be potentially used as biomarkers of sunitinib response.

Description of the EuroTARGET cohort: A European collaborative project on TArgeted therapy in renal cell cancer-GEnetic- and tumor-related biomarkers for response and toxicity

OBJECTIVE

For patients with metastatic renal cell cancer (mRCC), treatment choice is mainly based on clinical parameters. With many treatments available and the limited response to treatment and associated toxicities, there is much interest in identifying better biomarkers for personalized treatment. EuroTARGET aims to identify and characterize host- and tumor-related biomarkers for prediction of response to tyrosine kinase inhibitor therapy in mRCC. Here, we describe the EuroTARGET mRCC patient cohort.

METHODS AND MATERIALS

EuroTARGET is a European collaborative project designed as an observational study for which patients with mRCC were recruited prospectively in 62 centers. In addition, 462 patients with mRCC from previous studies were included. Detailed clinical information (baseline and follow-up) from all patients was entered in web-based case record forms. Blood was collected for germline DNA and pharmacokinetic/pharmacodynamic analyses and, where available, fresh-frozen tumor material was collected to perform tumor DNA, RNA, kinome, and methylome analyses.

RESULTS

In total, 1,210 patients with mRCC were included. Of these, 920 received a tyrosine kinase inhibitor as first-line targeted treatment (sunitinib [N = 713, 78%], sorafenib [N = 41, 4%], or pazopanib [N = 166, 18%]) and had at least 6 months of outcome assessment (median follow-up 15.3 months [interquartile range: 8.5-30.2 months]). Germline DNA samples were available from 824 of these patients, fresh-frozen tumor material from 142 patients, fresh-frozen normal kidney tissue from 95 patients, and tissue microarrays created from formalin-fixed paraffin-embedded tumor material from 247 patients. Of the 920 patients, germline DNA variant chip data were successfully generated for 811 patients (Illumina HumanOmniExpress BeadChip). For 80 patients, next-generation exome sequencing of germline and tumor DNA was performed, tumor RNA sequencing was performed for 124 patients, kinome activity measured and processed for 121 patients (PamChip), and methylome data (Illumina Infinium HumanMethylation450 BeadChip) were created for 116 RCC tissues (and 23 normal kidney tissues). For 73 out of the 920 patients, all platform data types were generated. In addition, 40 patients were included in a pharmacokinetic/pharmacodynamic phase IV substudy.

CONCLUSIONS

Analysis of EuroTARGET cohort data will contribute to personalization of therapy for patients with mRCC. The extensive clinical data and multiplatform EuroTARGET data will be freely available.

Assessment of ethnic differences in sunitinib outcome between Caucasian and Asian patients with metastatic renal cell carcinoma: a meta-analysis

BACKGROUND

An increasing number of studies have reported ethnic differences in sunitinib outcome in metastatic renal cell carcinoma (mRCC) patients. However, a comprehensive analysis is still lacking. Therefore, we systematically collected available published data and performed a meta-analysis to compare sunitinib efficacy and toxicity in Asian and Caucasian mRCC patients.

METHODS

Data were extracted from published results from clinical trials, expanded access program and real-world clinical practice. Progression-free survival (or time to tumor progression), overall survival, objective response rate and adverse events were used as endpoints to evaluate the differences of sunitinib outcome between the two ethnicities. For adverse events, we focused the following clinically relevant side effects: diarrhea, fatigue, mucositis/stomatitis, hand-foot syndrome, hypertension, leukopenia, neutropenia and thrombocytopenia.

RESULTS

A total of 33 publications including 9977 patients were available for meta-analysis. The efficacy of sunitinib in Asian patients was similar to that in Caucasian patients. However, Asian patients showed a higher incidence of all grades toxicity of hand-foot syndrome, > grade 2 fatigue, > grade 2 hand-foot syndrome and > grade 2 thrombocytopenia.

CONCLUSION

Ethnic differences in adverse events of sunitinib in mRCC patients existed and dose adjustment in Asian patients may be considered.

Molecular and Functional Diagnostic Tools in Precision Oncology for Urological Malignancies

Urological malignancies, represented mainly by prostate, bladder, and renal cancers, are some of the leading causes of cancer-related mortalities worldwide. Despite various efforts over decades to develop early detection tests and effective therapeutic paradigms, the response rate to the existing treatments remains low for both primary and late stage/recurrent phases of these cancers. The evolving landscape of molecular diagnostics, aiming to make the diagnosis and treatment more patient-driven, underpins precision oncology and particularly intends to rationally profile individual tumors and highlight the mechanistic insight and complexity of tumor microenvironment in order to develop biomarkers of toxicity risks and response prediction in a clinically oriented dynamical setting. The present review is an effort to capture some of the recent developments in the area of molecular diagnostics and functional testing platforms and their potential application in clinical decision making in the premises of precision oncology of urological malignancies.

Meta-analysis on the association of VEGFR1 genetic variants with sunitinib outcome in metastatic renal cell carcinoma patients

VEGFR1 rs9582036 and rs9554320 were previously reported the association with sunitinib progression-free survival (PFS) and overall survival (OS) in patients with metastatic renal cell carcinoma (mRCC). Hereafter, the association of both single nucleotide polymorphisms (SNPs) with PFS/OS was confirmed in two independent mRCC cohorts. The aim of the current study was to validate the associations of both SNPs with sunitinib outcome in three independent well-characterized cohorts (SUTOX, CCF and SOGUG) including 286 sunitinib-treated mRCC patients, as well as to perform a meta-analysis of current and published data combined. We found that rs9582036 and rs9554320 showed a significant association with sunitinib PFS in the CCF cohort (HR: 0.254, 95%CI: 0.092-0.703; P=0.008 and HR: 0.430, 95%CI: 0.200-0.927; P=0.031, respectively). Patients with the variant genotype of rs9582036 and rs9554320 had a shorter median PFS. No significant association of both SNPs with sunitinib PFS or OS was detected in either the SUTOX or SOGUG cohort. After the combination of all available data into a meta-analysis, the association of both SNPs with sunitinib PFS or OS did not achieve the threshold for statistical significance. Our findings suggest that, although VEGFR1 rs9582036 and rs9554320 are involved in sunitinib therapy outcome, its clinical use as biomarkers for prediction of sunitinib outcome in mRCC patients is limited, due to inconsistent findings when analyzing all existing studies together.

Strategies to design clinical studies to identify predictive biomarkers in cancer research

The discovery of reliable biomarkers to predict efficacy and toxicity of anticancer drugs remains one of the key challenges in cancer research. Despite its relevance, no efficient study designs to identify promising candidate biomarkers have been established. This has led to the proliferation of a myriad of exploratory studies using dissimilar strategies, most of which fail to identify any promising targets and are seldom validated. The lack of a proper methodology also determines that many anti-cancer drugs are developed below their potential, due to failure to identify predictive biomarkers. While some drugs will be systematically administered to many patients who will not benefit from them, leading to unnecessary toxicities and costs, others will never reach registration due to our inability to identify the specific patient population in which they are active. Despite these drawbacks, a limited number of outstanding predictive biomarkers have been successfully identified and validated, and have changed the standard practice of oncology. In this manuscript, a multidisciplinary panel reviews how those key biomarkers were identified and, based on those experiences, proposes a methodological framework-the DESIGN guidelines-to standardize the clinical design of biomarker identification studies and to develop future research in this pivotal field.

Sunitinib side effects as surrogate biomarkers of efficacy

With the proliferation of treatment options for the management of metastatic renal cell carcinoma (mRCC) over the past decade, predictive markers of response to therapy are becoming increasingly important. Sunitinib is commonly used in the first-line treatment of mRCC. Common mechanism-based adverse events, including hypertension, hypothyroidism, hand-foot syndrome, and neutropenia, have been explored as potential biomarkers of the clinical efficacy of sunitinib in mRCC and are reviewed in this article.

Pharmacogenomic Markers of Targeted Therapy Toxicity in Patients with Metastatic Renal Cell Carcinoma

BACKGROUND

Targeted therapy (TT) in metastatic renal cell carcinoma (mRCC) may be associated with a high rate of toxicity that undermines treatment efficacy and patient quality of life. Polymorphisms in genes involved in the pharmacokinetic pathways of TTs may predict toxicity.

OBJECTIVE

To investigate whether selected single-nucleotide polymorphisms (SNPs) in three core genes involved in the metabolism and transport of sunitinib and the mTOR inhibitors everolimus and temsirolimus are associated with adverse events (AEs).

DESIGN, SETTING, AND PARTICIPANTS

Germline DNA was extracted from blood or normal kidney tissue from mRCC patients of Caucasian ethnicity in two cohorts treated with either sunitinib (n=159) or mTOR inhibitors (n=62). Six SNPs in three candidate genes (CYP3A4: rs2242480, rs4646437, and rs2246709; CYP3A5: rs15524; and ABCB1: rs2032582 and rs1045642) were analyzed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Primary endpoints were grade ≥3 AEs for all patients; grade ≥3 hypertension in the sunitinib cohort, and any grade pneumonitis in the mTOR inhibitors cohort. A logistic regression model was used to assess the association between SNPs and AEs, with adjustment for relevant clinical factors.

RESULTS AND LIMITATIONS

In total, 221 samples were successfully genotyped for the selected SNPs. In the sunitinib cohort, the CYP3A4 rs464637 AG variant was associated with a lower risk of high-grade AEs (odds ratio 0.27, 95% confidence interval 0.08-0.88; p=0.03), but no SNPs were associated with hypertension. In the mTOR inhibitor cohort, none of the selected SNPs was associated with analyzed toxicities.

CONCLUSIONS

We observed an association between CYP3A4 polymorphisms and toxicity outcomes in mRCC patients treated with sunitinib, but not with everolimus or temsirolimus. Our findings are exploratory in nature, and further validation in independent and larger cohorts is needed.

PATIENT SUMMARY

We found that variants of CYP3A4, a gene involved in drug metabolism, are associated with sunitinib toxicity. This information may help in better selection of patients for targeted therapies in metastatic renal cell carcinoma.

Impact of Membrane Drug Transporters on Resistance to Small-Molecule Tyrosine Kinase Inhibitors

Small-molecule inhibitors of tyrosine kinases (TKIs) are the mainstay of treatment for many malignancies and represent novel treatment options for other diseases such as idiopathic pulmonary fibrosis. Twenty-five TKIs are currently FDA-approved and >130 are being evaluated in clinical trials. Increasing evidence suggests that drug exposure of TKIs may significantly contribute to drug resistance, independently from somatic variation of TKI target genes. Membrane transport proteins may limit the amount of TKI reaching the target cells. This review highlights current knowledge on the basic and clinical pharmacology of membrane transporters involved in TKI disposition and their contribution to drug efficacy and adverse drug effects. In addition to non-genetic and epigenetic factors, genetic variants, particularly rare ones, in transporter genes are promising novel factors to explain interindividual variability in the response to TKI therapy.

BSA and ABCB1 polymorphism affect the pharmacokinetics of sunitinib and its active metabolite in Asian mRCC patients receiving an attenuated sunitinib dosing regimen

PURPOSE

An attenuated dosing (AD) sunitinib regimen of 37.5 mg daily has been suggested to reduce the toxicity reported with the standard dosing regimen to metastatic renal cell carcinoma (mRCC) patients. The aim of this study was to characterize the population pharmacokinetic (PK) properties of sunitinib and SU12662, the active metabolite, in patients receiving the AD regimen and to ascertain significant covariates influencing PK parameters.

METHODS

Thirty-one mRCC patients receiving AD sunitinib regimen were included. Plasma samples were collected on day 29 of each treatment cycle after the start of the therapy. Nonlinear mixed-effects modeling was applied to estimate the population PK properties of sunitinib and SU12662 as well as the effect of covariates on PK parameters. Monte Carlo simulation was also performed to predict the total trough level (TTL) of sunitinib and SU12662.

RESULTS

Sunitinib population means for CL/F and V d /F central were 13.8 L/h and 1720 L, respectively. SU12662 population means for CL/F and V d /F were 42.1 L/h and 1410 L, respectively. Body surface area (BSA) and ABCB1 polymorphism significantly influenced the CL/F variability of sunitinib: CL/F parent = 13.8 × exp((BSA - 1.75) × 2.08 + (ABCB1 genotype - 0.67) × 0.61), ABCB1-0: wild genotype, 1: mutant genotype. The effect size of ABCB1 mutant genotype and BSA greater than 1.75 m(2) in relation to sunitinib clearance was 31.14 % (p = 0.006) and 22.11 % (p = 0.011), respectively, relative to the reference group.

CONCLUSIONS

Adjusting doses of sunitinib according to BSA and ABCB1 polymorphism in Asian mRCC patients may be recommended for sufficient attainment of a target TTL of sunitinib and its metabolite.

Deep sequencing reveals microRNAs predictive of antiangiogenic drug response

The majority of metastatic renal cell carcinoma (RCC) patients are treated with tyrosine kinase inhibitors (TKI) in first-line treatment; however, a fraction are refractory to these antiangiogenic drugs. MicroRNAs (miRNAs) are regulatory molecules proven to be accurate biomarkers in cancer. Here, we identified miRNAs predictive of progressive disease under TKI treatment through deep sequencing of 74 metastatic clear cell RCC cases uniformly treated with these drugs. Twenty-nine miRNAs were differentially expressed in the tumors of patients who progressed under TKI therapy (P values from 6 × 10^-9 to 3 × 10^-3). Among 6 miRNAs selected for validation in an independent series, the most relevant associations corresponded to miR-1307-3p, miR-155-5p, and miR-221-3p (P = 4.6 × 10^-3, 6.5 × 10^-3, and 3.4 × 10^-2, respectively). Furthermore, a 2 miRNA-based classifier discriminated individuals with progressive disease upon TKI treatment (AUC = 0.75, 95% CI, 0.64-0.85; P = 1.3 × 10^-4) with better predictive value than clinicopathological risk factors commonly used. We also identified miRNAs significantly associated with progression-free survival and overall survival (P = 6.8 × 10^-8 and 7.8 × 10^-7 for top hits, respectively), and 7 overlapped with early progressive disease. In conclusion, this is the first miRNome comprehensive study, to our knowledge, that demonstrates a predictive value of miRNAs for TKI response and provides a new set of relevant markers that can help rationalize metastatic RCC treatment.

Evaluation of polymorphisms in angiogenesis-related genes as predictive and prognostic markers for sunitinib-treated metastatic renal cell carcinoma patients

PURPOSE

Single nucleotide polymorphisms (SNPs) in angiogenesis-associated genes might play an important role in activity of the tyrosine kinase inhibitor sunitinib and could affect survival of cancer patients treated with this drug. The aim of this retrospective study was to elucidate the role of 10 known SNPs in VEGFA, VEGFR1, VEGFR2 and VEGFR3 as potential prognostic and predictive markers in an independent cohort of patients with metastatic renal cell carcinoma (mRCC).

METHODS

DNA from 121 mRCC patients treated with sunitinib was used to analyze SNPs by TaqMan genotyping assays. Disease control rate was evaluated according to RECIST. Adverse effects of sunitinib were registered from medical records. The results of Cox and logistic regression were verified by correction for multiple testing.

RESULTS

Kaplan-Meier analysis revealed a reduced progression-free survival in patients with the wild-type (WT) allele of the VEGFA SNP rs699947 compared to variant alleles. Patients with the AA/AC-alleles of the VEGFR1 SNP rs9582036 had an improved median overall survival compared to those with the CC-WT allele what could be confirmed by multivariable Cox proportional hazard regression analyses. No statistically significant associations between the analyzed SNPs and higher risk for adverse effects were observed.

CONCLUSIONS

The results of this study suggest that most of the selected SNPs in angiogenesis-related genes are not associated with survival of mRCC patients after sunitinib therapy or with adverse effects. Only the VEGFR1 SNP rs9582036 showed a statistically significant association with overall survival. The potential of SNPs as prognostic and predictive markers for sunitinib-treated mRCC patients should be finally assessed by prospective studies.

The evolving landscape of metastatic renal cell carcinoma

The treatment paradigm in metastatic renal cell carcinoma (mRCC) has evolved over the last 5 years. There are now seven approved targeted therapies against the vascular endothelial growth factor (VEGF) and mammalian target of rapamycin (mTOR) pathways. The use of targeted therapy, sequences, combinations, and investigational compounds will be discussed. Prognostic and predictive tools are detailed, although much work must be done to find predictive biomarkers in an effort to individualize therapy for patients.

The genetics of drug efficacy: opportunities and challenges

Lack of sufficient efficacy is the most common cause of attrition in late-phase drug development. It has long been envisioned that genetics could drive stratified drug development by identifying those patient subgroups that are most likely to respond. However, this vision has not been realized as only a small proportion of drugs have been found to have germline genetic predictors of efficacy with clinically meaningful effects, and so far all but one were found after drug approval. With the exception of oncology, systematic application of efficacy pharmacogenetics has not been integrated into drug discovery and development across the industry. Here, we argue for routine, early and cumulative screening for genetic predictors of efficacy, as an integrated component of clinical trial analysis. Such a strategy would identify clinically relevant predictors that may exist at the earliest possible opportunity, allow these predictors to be integrated into subsequent clinical development and provide mechanistic insights into drug disposition and patient-specific factors that influence response, therefore paving the way towards more personalized medicine.

Recent aspects of sunitinib therapy in patients with metastatic clear-cell renal cell carcinoma: a systematic review of the literature

Sunitinib is an orally available inhibitor of multiple tyrosine-kinase receptors approved for the treatment of advanced clear-cell renal cell carcinoma (ccRCC), a disease which has habitually had a very poor patient survival rate. Although it has become the most widely used drug for this disease, it remains not completely clear the best treatment strategy with these agent. The aim of this review is to highlight the most recent and interesting aspects of the research on treatment of advanced ccRCC with sunitinib and eventually determine alternative treatment schedule to reduce the incidence of side effects; we also wanted to review recent biomarkers able to predict response to therapy and also to point out the mechanism of acquired resistance to this drug.

Impact of Genetic Polymorphisms of ABCB1 (MDR1, P-Glycoprotein) on Drug Disposition and Potential Clinical Implications: Update of the Literature

ATP-binding cassette transporter B1 (ABCB1; P-glycoprotein; multidrug resistance protein 1) is an adenosine triphosphate (ATP)-dependent efflux transporter located in the plasma membrane of many different cell types. Numerous structurally unrelated compounds, including drugs and environmental toxins, have been identified as substrates. ABCB1 limits the absorption of xenobiotics from the gut lumen, protects sensitive tissues (e.g. the brain, fetus and testes) from xenobiotics and is involved in biliary and renal secretion of its substrates. In recent years, a large number of polymorphisms of the ABCB1 [ATP-binding cassette, sub-family B (MDR/TAP), member 1] gene have been described. The variants 1236C>T (rs1128503, p.G412G), 2677G>T/A (rs2032582, p.A893S/T) and 3435C>T (rs1045642, p.I1145I) occur at high allele frequencies and create a common haplotype; therefore, they have been most widely studied. This review provides an overview of clinical studies published between 2002 and March 2015. In summary, the effect of ABCB1 variation on P-glycoprotein expression (messenger RNA and protein expression) and/or activity in various tissues (e.g. the liver, gut and heart) appears to be small. Although polymorphisms and haplotypes of ABCB1 have been associated with alterations in drug disposition and drug response, including adverse events with various ABCB1 substrates in different ethnic populations, the results have been majorly conflicting, with limited clinical relevance. Future research activities are warranted, considering a deep-sequencing approach, as well as well-designed clinical studies with appropriate sample sizes to elucidate the impact of rare ABCB1 variants and their potential consequences for effect sizes.

A decade of pharmacogenomics research on tyrosine kinase inhibitors in metastatic renal cell cancer: a systematic review

OBJECTIVE

The individual response to targeted tyrosine kinase inhibitors (TKIs) in the treatment of metastatic renal cell cancer (mRCC) is highly variable. Outlined in this article are findings on potential biomarkers for TKI treatment outcome in mRCC and an evaluation of the status of clinical implementation.

METHODS

Articles were selected by two independent reviewers using a systematic search in five medical databases on renal cell carcinoma, TKIs, and pharmacogenetics.

RESULTS

Many researchers have focused on predictive biomarkers for treatment outcome of targeted therapies in mRCC patients. Attempts to explain differences in efficacy and toxicity of TKIs by use of genetic variants in genes related to the pharmacokinetics and pharmacodynamics of the drug have been successful.

CONCLUSION

Most findings on potential biomarkers have not been validated and therefore biomarker testing to guide choice of therapy and dose in mRCC is not yet feasible.

The influence of genetic variants of sorafenib on clinical outcomes and toxic effects in patients with advanced renal cell carcinoma

The purpose of the present study was to investigate whether genetic variants that influence angiogenesis and sorafenib pharmacokinetics are associated with clinical outcomes and toxic effects in advanced renal cell carcinoma patients treated with this drug. One hundred patients with advanced renal cell carcinoma were enrolled. Forty-two polymorphisms in 15 genes were selected for genotyping and analyzed for associations with progression-free survival, overall survival, and toxic effects. We found that rs1570360 in VEGF and rs2239702 in VEGFR2 were significantly associated with progression-free. Specifically, patients carrying the variant genotypes (AG + AA) of these two polymorphisms both had an unfavorable progression-free. In addition, compared with those with the rs2239702 GG genotype, patients with the AG + AA genotype suffered an unfavorable OS. We found that the VEGF rs2010963 CG + GG genotypes had a significantly increased risk of hand-foot syndrome, and the ABCB1 rs1045642 CT + TT genotypes had an increased risk of high blood pressure. Our results suggest that polymorphisms in VEGF and VEGFR2 are associated with sorafenib clinical outcomes, and polymorphisms in VEGF and ABCB1 are associated with sorafenib-related toxicities. Larger studies are warranted to validate our findings.

Sunitinib-induced hypertension in CYP3A4 rs4646437 A-allele carriers with metastatic renal cell carcinoma

The single nucleotide polymorphism (SNP) rs4646437G>A in CYP3A4 was suggested to be related to sunitinib toxicity. Our objective was to perform an in-depth investigation of the association between this SNP and sunitinib toxicity and efficacy using a large cohort of metastatic renal cell carcinoma (mRCC) patients. We collected DNA and clinical information of mRCC patients treated with sunitinib. SNP rs4646437 in CYP3A4 was tested for associations with toxicity using logistic regression. Cox regression modeling was used for association analysis of rs4646437 with progression-free survival (PFS) and overall survival (OS). In a total of 287 patients, the A-allele of CYP3A4 rs4646437 was associated with an increased risk for hypertension (odds ratio=2.4, 95% confidence interval: 1.1-5.2, P=0.021) and showed no significant association with PFS or OS. In conclusion, hypertension is more likely to occur in A-allele carriers of the CYP3A4 rs4646437 variant in our cohort of mRCC patients treated with sunitinib.

A case for the use of receiver operating characteristic analysis of potential clinical efficacy biomarkers in advanced renal cell carcinoma

AIM

Assess patient-level utility of suggested pretreatment biomarkers of sunitinib in advanced renal cell carcinoma.

PATIENTS & METHODS

Kaplan-Meier analysis of data from a randomized, Phase II study (n = 292) suggested baseline predictive value for circulating soluble Ang-2 and MMP-2 and HIF-1α percentage of tumor expression. Using this dataset, the sensitivity, specificity and area under the curve (AUC) were calculated, using receiver operating characteristic (ROC) curves.

RESULTS

Based on a ROC (sensitivity vs 1 - specificity) threshold AUC value of >0.8, neither Ang-2 (0.67) nor MMP-2 (0.65), nor HIF-1α percentage of tumor expression (0.65), performed appropriately from a patient-selection standpoint.

CONCLUSION

To properly assess potential biomarkers, sensitivity and specificity characteristics should be obtained by ROC analysis.

Efficacy and toxicity of sunitinib in metastatic renal cell carcinoma patients in Egypt

BACKGROUND

To evaluate our results in terms of response, survival and toxicity profile of sunitinib among Egyptian patients with metastatic renal cell carcinoma.

MATERIALS AND METHODS

Between January 2010 and December 2013, 44 patients with metastatic renal cell carcinoma who received sunitinib at an oncology center of Cairo university hospitals were enrolled in this retrospective analysis.

RESULTS

The median age of the patients was 53 years, 22 (50%) having localized disease at presentation ,while the remaining half of the patients presented with metastasis. At a median follow up of 19 months, 9 (21%) patients achieved partial remission, while disease was reported stable in 20 cases (45%) and progressive in 7 (16%), 4 (9%) being lost to follow up, and 4 (9%) had discontinued therapy due to toxicity. The median overall survival was 23 months (95%CI 15.2 - 30.9), while progression free survival was 12 months (95%CI 11.6 - 12.3). The most commonly reported non hematological grade 3 adverse events included mucositis (15.9%), hand-foot syndrome (13.6%), and fatigue (9%), while the predominant grade 3 or 4 laboratory abnormalities were neutropenia (6.8%), followed by anemia in 4.5% of patients.

CONCLUSIONS

Our efficacy data were comparable to the published literature in terms of progression free survival and overall survival , while toxicity profile is different from Asian and western countries. However, sunitinib adverse events were manageable and tolerable in most of our Egyptian patients.

Sunitinib-associated hypertension and neutropenia as efficacy biomarkers in metastatic renal cell carcinoma patients

BACKGROUND

Metastatic renal cell carcinoma (mRCC) prognostic models may be improved by incorporating treatment-induced toxicities.

METHODS

In sunitinib-treated mRCC patients (N=770), baseline prognostic factors and treatment-induced toxicities (hypertension (systolic blood pressure ⩾140 mm Hg), neutropenia (grade ⩾2), thrombocytopenia (grade ⩾2), hand-foot syndrome (grade >0), and asthenia/fatigue (grade >0)) were analysed in multivariate analyses of progression-free survival (PFS) and overall survival (OS) end points.

RESULTS

On-treatment neutropenia and hypertension were associated with longer PFS (P=0.0276 and P<0.0001, respectively) and OS (P=0.0014 and P<0.0001, respectively), independent of baseline prognostic factors, including International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) criteria. By 12-week landmark analysis, neutropenia was significantly associated with longer PFS and OS (P=0.013 and P=0.0122, respectively) and hypertension or hand-foot syndrome with longer OS (P=0.0036 and P=0.0218, respectively). The concordance index was 0.65 (95% CI: 0.63-0.67) for IMDC classification alone and 0.72 (95% CI: 0.70-0.74) when combined with hypertension and neutropenia. Considering hypertension and neutropenia (developing both vs neither) changed IMDC-predicted median OS in each IMDC risk group (favourable: 45.3 vs 19.5 months; intermediate: 32.5 vs 8.0 months; poor: 21.1 vs 4.8 months).

CONCLUSIONS

On-treatment neutropenia and hypertension are independent biomarkers of sunitinib efficacy and may add prognostic accuracy to the IMDC model.

Prognostic Biomarkers for Response to Vascular Endothelial Growth Factor-Targeted Therapy for Renal Cell Carcinoma

Improved understanding of renal carcinoma disease biology has led to the discovery and approval of five novel therapies targeting specific molecules in the vascular endothelial growth factor (VEGF) biochemical pathway. Biomarker studies attempting to predict response to VEGF-targeted therapies have largely focused on circulating proteins, tissue-based molecules, and germline polymorphisms. Thus far studies have yielded conflicting results that require prospective validation; therefore no definitive biomarker has yet been integrated into the clinician's armamentarium. However, early analyses featuring genomic biomarkers have generated promising findings. This article provides an overview of available biomarkers evaluated with respect to VEGF-targeted therapies in patients with advanced renal cell carcinoma.

Molecular and immunologic markers of kidney cancer-potential applications in predictive, preventive and personalized medicine

Kidney cancer is one of the deadliest malignancies due to frequent late diagnosis (33 % or renal cell carcinoma are metastatic at diagnosis) and poor treatment options. There are two major subtypes of kidney cancer: renal cell carcinoma (RCC) and renal pelvis carcinoma. The risk factors for RCC, accounting for more than 90 % of all kidney cancers, are smoking, obesity, hypertension, misuse of pain medication, and some genetic diseases. The most common molecular markers of kidney cancer include mutations and epigenetic inactivation of von Hippel-Lindau (VHL) gene, genes of vascular endothelial growth factor (VEGF) pathway, and carbonic anhydrase IX (CIAX). The role of epigenetic pathways, including DNA methylation and chromatin structure remodeling, was also demonstrated. Immunologic properties of RCC enable this type of tumor to escape immune response effectively. An important role in this process is played by tumor-associated macrophages that demonstrate mixed M1/M2 phenotype. In this review, we discuss molecular and cellular aspects for RCC development and current state of knowledge allowing personalized approaches for diagnostics and prognostic prediction of this disease. A set of macrophage markers is suggested for the analysis of the association of macrophage phenotype and disease prognosis.

High Throughput Kinomic Profiling of Human Clear Cell Renal Cell Carcinoma Identifies Kinase Activity Dependent Molecular Subtypes

Despite the widespread use of kinase-targeted agents in clear cell renal cell carcinoma (CC-RCC), comprehensive kinase activity evaluation (kinomic profiling) of these tumors is lacking. Thus, kinomic profiling of CC-RCC may assist in devising a classification system associated with clinical outcomes, and help identify potential therapeutic targets. Fresh frozen CC-RCC tumor lysates from 41 clinically annotated patients who had localized disease at diagnosis were kinomically profiled using the PamStation®12 high-content phospho-peptide substrate microarray system (PamGene International). Twelve of these patients also had matched normal kidneys available that were also profiled. Unsupervised hierarchical clustering and supervised comparisons based on tumor vs. normal kidney and clinical outcome (tumor recurrence) were performed and coupled with advanced network modeling and upstream kinase prediction methods. Unsupervised clustering analysis of localized CC-RCC tumors identified 3 major kinomic groups associated with inflammation (A), translation initiation (B), and immune response and cell adhesions (C) processes. Potential driver kinases implicated include PFTAIRE (PFTK1), PKG1, and SRC, which were identified in groups A, B, and C, respectively. Of the 9 patients who had tumor recurrence, only one was found in Group B. Supervised analysis showed decreased kinase activity of CDK1 and RSK1-4 substrates in those which progressed compared to others. Twelve tumors with matching normal renal tissue implicated increased PIM's and MAPKAPK's in tumors compared to adjacent normal renal tissue. As such, comprehensive kinase profiling of CC-RCC tumors could provide a functional classification strategy for patients with localized disease and identify potential therapeutic targets.

Association of single nucleotide polymorphisms in IL8 and IL13 with sunitinib-induced toxicity in patients with metastatic renal cell carcinoma

Purpose

Earlier, the association of single nucleotide polymorphisms (SNPs) with toxicity and efficacy of sunitinib has been explored in patients with metastatic renal cell carcinoma (mRCC). Recently, additional SNPs have been suggested as potential biomarkers. We investigated these novel SNPs for association with sunitinib treatment outcome in mRCC patients.

Methods

In this exploratory study, we selected SNPs in genes CYP3A4, NR1I2, POR, IL8, IL13, IL4-R, HIF1A and MET that might possibly be associated with sunitinib treatment outcome. Each SNP was tested for association with progression-free survival (PFS) and overall survival (OS) by Cox-regression analysis and for clinical response and toxicity using logistic regression.

Results

We included 374 patients for toxicity analyses, of which 38 patients with non-clear cell renal cell cancer were excluded from efficacy analyses. The risk for hypertension was increased in the presence of the T allele in IL8 rs1126647 (OR = 1.69, 95 % CI = 1.07–2.67, P = 0.024). The T allele in IL13 rs1800925 was associated with an increase in the risk of leukopenia (OR = 6.76, 95 % CI = 1.35–33.9, P = 0.020) and increased prevalence of any toxicity > grade 2 (OR = 1.75, 95 % CI = 1.06–2.88, P = 0.028). No significant associations were found with PFS, OS or clinical response.

Conclusions

We show that polymorphisms in IL8 rs1126647 and IL13 rs1800925 are associated with sunitinib-induced toxicities. Validation in an independent cohort is required.

Electronic supplementary material

The online version of this article (doi:10.1007/s00228-015-1935-7) contains supplementary material, which is available to authorized users.

Safety, efficacy and prognostic analyses of sunitinib in the post-marketing surveillance study of Japanese patients with gastrointestinal stromal tumor

OBJECTIVE

This study was conducted to expand the sunitinib safety database in Japanese imatinib-resistant/-intolerant gastrointestinal stromal tumor patients. Retrospective analyses investigated common adverse events as potential prognostic markers.

METHODS

Four hundred and seventy patients who received sunitinib between June 2008 and November 2009 were analyzed for safety, progression-free survival and overall survival; 386 for objective response rate; 88% received sunitinib on Schedule 4/2 starting at 50 mg/day.

RESULTS

No unexpected safety issues occurred. Grade ≥ 3 adverse events occurred in 70%, most commonly thrombocytopenia (33%), neutropenia (22%) and leukopenia (15%). Objective response rate was 20% (95% confidence interval 16-24). Median progression-free survival was 22.4 weeks (95% confidence interval, 21.7-24.0). The overall survival rate at 24 weeks was 91% (95% confidence interval, 88-94). Higher relative dose intensity (≥70 vs. <70%) during the first 6 weeks and better Eastern Cooperative Oncology Group performance status (0 vs. ≥1) were associated with longer progression-free survival (24.0 vs. 20.1 weeks; P = 0.011; and 24.1 vs. 16.9 weeks; P < 0.001) and higher 24-week overall survival rate (94 vs. 83%; P < 0.001; and 96 vs. 83%; P < 0.001). Increased progression-free survival and overall survival rates were associated with specific adverse events. Cox proportional hazard modeling adjusted for relative dose intensity and performance status established hand-foot syndrome (hazard ratio = 0.636; 95% confidence interval, 0.456-0.888) and leukopenia (hazard ratio = 0.683; 95% confidence interval, 0.492-0.948) occurring within 12 weeks were significantly correlated with increased progression-free survival.

CONCLUSION

Sunitinib showed good efficacy and tolerable safety. Factors associated with greater efficacy were relative dose intensity, performance status and specific early adverse events.

Pretreatment neutrophil-to-lymphocyte ratio predicts prognosis in patients with metastatic renal cell carcinoma receiving targeted therapy

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) is associated with clinical outcomes of various cancers. This study aimed to evaluate whether pretreatment NLR can be used as a prognostic factor in patients with metastatic renal cell carcinoma (mRCC) receiving targeted therapy.

METHODS

In this single-center retrospective study, the Kaplan-Meier method was used to estimate progression-free survival (PFS) and overall survival (OS) of 373 mRCC patients receiving targeted therapy. The survival outcomes of patients with high (≥ 2.2) and low (< 2.2) pretreatment NLRs were compared by log-rank test, and Cox proportional hazard regression model was used to compare OS and PFS between groups.

RESULTS

The overall median PFS and OS times for all 373 patients were 18.4 and 34.3 months, respectively. Patients with high NLRs had significantly shorter median OS (28.8 vs 410 months, P = 0.005) and PFS (15.4 vs 23.9 months, P = 0.001) than those with low NLRs. After adjusting for confounding variables, each unit increase of NLR was associated with a 40 % increase in mortality (hazard ratio [HR] 1.391; 95 % confidence interval [CI] 1.022-1.894; P = 0.036). High NLR was also an independent predictor of poor PFS (HR 1.544; 95 % CI 1.166-2.045; P = 0.002).

CONCLUSION

Pretreatment NLR may be an independent prognostic factor for mRCC patients who are receiving targeted therapy.

Incidence and risk of hypertension with bevacizumab in non-small-cell lung cancer patients: a meta-analysis of randomized controlled trials

Aim

A study was conducted to determine the overall risk and incidence of hypertension with bevacizumab in non-small-cell lung cancer (NSCLC) patients.

Materials and methods

Electronic databases such as the Embase, PubMed, and Cochrane Library were searched for related trials. Statistical analyses were conducted to calculate the overall incidence rates, odds ratios (ORs), and 95% confidence intervals (CIs) by using either random-effect or fixed-effect models depending on the heterogeneity.

Results

A total of 3,155 subjects from nine studies were included. The overall incidences of all-grade and high-grade hypertension in NSCLC patients were 19.55% (95% CI 10.17%–34.3%) and 6.95% (95% CI 5.81%–8.30%). Bevacizumab use was associated with a significantly increased risk in all-grade hypertension (OR 8.07, 95% CI 3.87–16.85; P=0.0002) and high-grade hypertension (OR 5.93, 95% CI 3.41–10.32; P<0.0001). No evidence of publication bias was determined for the ORs of hypertension in our meta-analysis.

Conclusion

Bevacizumab is associated with a significantly increased risk of hypertension development in NSCLC patients. Early monitoring and effective management of hypertension might be important steps for the safe use of this drug.

Impact of VEGF, VEGFR, PDGFR, HIF and ERCC1 gene polymorphisms on thymic malignancies outcome after thymectomy

We aimed to analyze genotypes of VEGF-A, VEGFR2, Flt4, PDGFRα, HIF-1α and ERCC1 and their correlation with thymic tumor risk and patient outcome. DNA of 57 consecutive patients (43 thymomas and 14 thymic carcinomas) who underwent total thymectomy at our Institution was extracted from paraffin-embedded tissue. We selected polymorphisms in the following genes:HIF1-α (rs2057482T > C, rs1951795A > C, rs2301113C > A, rs10873142C > T, rs11158358G > C, rs12434438G > A, rs11549465C > T, rs11549467G > A), VEGF-A (rs2010963G > C, rs699947A > C), VEGFR-2 (rs2305948C > T, rs1870377T > A), VEGFR-3 (rs307826T > C, rs307821C > A), PDGFR-α (rs35597368C > T) and ERCC1 (rs11615A > G). Gene polymorphisms were determined by Real-Time PCR using TaqMan assays. As compared to the general population, the allele frequency of PDGFR-α rs35597368T was significantly higher (95% vs. 87%, p = 0.036), while the frequency of alleles HIF1-α rs2057482C (78% vs. 90%), rs1951795C (69% vs. 87%), rs2301113A (70% vs. 83%), rs10873142T (70% vs. 87%), rs11158358C (75% vs. 88%), rs12434438A (67% vs. 84%) were significantly lower. VEGFR-3 rs307821C frequency was significantly higher in thymomas vs. thymic carcinomas (79% vs. 72%, p = 0.0371). The following factors were significantly correlated with a longer overall survival: VEGFR-3 rs307826C, VEGFR-2 rs1870377A, PDGFR-α rs35597368T/C, HIF1-α rs2301113C, rs2057482C/T, rs1951795C, rs11158358G/C and rs10873142T/C, ERCC1 rs11615A (p < 0.05). Our results suggest, for the first time, that PDGFR-α, HIF-1α and VEGFR-3 SNPs are associated with thymic cancer risk and survival.

Association of ABCB1 and FLT3 Polymorphisms with Toxicities and Survival in Asian Patients Receiving Sunitinib for Renal Cell Carcinoma

Sunitinib is a tyrosine kinase inhibitor used as first-line treatment for metastatic renal cell carcinoma (mRCC). Asian ethnicity has been previously associated with lower clearance and greater toxicities for sunitinib treatment, relative to Caucasian ethnicity. Research focusing on identifying corresponding biomarkers of efficacy and toxicity has been hitherto conducted in Caucasian populations, and few of the reported associations have been externally validated. Our work thus aims to investigate candidate biomarkers in Asian patients receiving sunitinib, comparing the observed genotype effects with those reported in Caucasian populations. Using data from 97 Asian mRCC patients treated with sunitinib, we correlated 7 polymorphisms in FLT3, ABCB1, VEGFR2, ABCG2 and BIM with patient toxicities, response, and survival. We observed a stronger association of FLT3 738T genotype with leucopenia in our Asian dataset than that previously reported in Caucasian mRCC patients (odds ratio [OR]=8.0; P=0.03). We observed significant associations of FLT3 738T (OR=2.7), ABCB1 1236T (OR=0.3), ABCB1 3435T (OR=0.1), ABCB1 2677T (OR=0.4), ABCG2 421A (OR=0.3) alleles and ABCB1 3435, 1236, 2677 TTT haplotype (OR=0.1) on neutropenia. Primary resistance (OR=0.1, P=0.004) and inferior survival (progression-free: hazard ratio [HR]=5.5, P=0.001; overall: HR=5.0, P=0.005) were associated with the ABCB1 3435, 1236, 2677 TTT haplotype. In conclusion, ABCB1 and FLT3 polymorphisms may be helpful in predicting sunitinib toxicities, response and survival benefit in Asian mRCC patients. We have also validated the association between FLT3 738T and sunitinib-induced leucopenia previously reported in Caucasian populations, but have not validated other reported genetic associations.

Predictive biomarker candidates to delineate efficacy of antiangiogenic treatment in renal cell carcinoma

Antiangiogenic therapy is currently considered as the cornerstone of treatment in metastatic kidney cancer. A monoclonal antibody against the vascular endothelial growth factor (VEGF) and several tyrosine kinase inhibitors targeting the VEGF receptors demonstrated, 7 years ago, to deeply impact the outcome of this tumor and became a model of integration of molecular knowledge into clinical practice. Unfortunately, no further improvement in survival has been made and 20-25 % of cases remain primary refractory to these drugs, with an overall dismal prognosis. Since biomarker predictors of activity are lacking, their development could highly help in the process of making clinical decisions when choosing the best option for every patient or prompting the inclusion in clinical trials. This unmet medical need could become even more relevant if new immunotherapy confirms its initial promising results in this pathology. In this article, we provide an insight of current state of the art regarding the prediction of antiangiogenic efficacy in kidney cancer and propose new strategies for the implementation of such markers in clinical practice.

Pazopanib in pretreated advanced neuroendocrine tumors: a phase II, open-label trial of the Spanish Task Force Group for Neuroendocrine Tumors (GETNE)

BACKGROUND

The management of advanced neuroendocrine tumors (NETs) has recently changed. We assessed the activity of pazopanib after failure of other systemic treatments in advanced NETs.

METHODS

This was a multicenter, open-label, phase II study evaluating pazopanib as a single agent in advanced NETs (PAZONET study). The clinical benefit rate (CBR) at 6 months was the primary end point. Translational correlation of radiological response and progression-free survival (PFS) with circulating and tissue biomarkers was also evaluated.

RESULTS

A total of 44 patients were enrolled. Twenty-five patients (59.5%) were progression-free at 6 months (4 partial responses, 21 stable diseases) with a median PFS of 9.5 months [95% confidence interval (CI) 4.8-14.1]. The CBR varied according to prior therapy received, with 73%, 60% and 25% in patients treated with prior multitarget inhibitors, prior mTOR inhibitors and both agents, respectively. A nonsignificant increase in PFS was observed in patients presenting lower baseline circulating tumor cell (CTC) counts (9.1 versus 5.8 months; P = 0.22) and in those with decreased levels of soluble-vascular endothelial growth factor receptor-2 (sVEGFR-2) (12.6 versus 9.1 months; P = 0.067). A trend toward reduced survival was documented in patients with VEGFR3 rs307821 and rs307826 missense polymorphisms [hazard ratio (HR): 12.3; 95% CI 1.09-139.2; P = 0.042 and HR: 6.9; 95% CI 0.96-49.9; P = 0.055, respectively].

CONCLUSIONS

Pazopanib showed clinical activity in patients with advanced NETs regardless of previous treatments. Additionally, CTCs, soluble-s VEFGR-2 and VEGFR3 gene polymorphisms constitute potential biomarkers for selecting patients for pazopanib (NCT01280201).

CLINICAL TRIAL NUMBER

NCT01280201.

A case of metastatic renal cell carcinoma and bile duct carcinoma treated with a combination of sunitinib and gemcitabine

BACKGROUND

Metastatic renal cell carcinoma (mRCC) had been a chemo-refractory disease, but recent advances in multiple kinase inhibitors such as sunitinib have dramatically changed the clinical course of mRCC. Sunitinib is used for mRCC chemotherapy based on the favorable results of a recent clinical trial, but specific biomarkers predicting efficacy and safety are not yet available. Locally advanced bile duct carcinoma (BDC) has generally been treated with single agent gemcitabine or as doublet therapy with cisplatin. Concomitant occurrence of mRCC and BDC is extremely rare, and a standard therapeutic strategy has not been established.

CASE PRESENTATION

A 65-year-old woman was diagnosed as having multiple mRCC and intercurrent, locally advanced BDC. A single course of combination therapy with sunitinib (25 mg/day, day2-15) and gemcitabine (750 mg/m(2), days 1, 8) was administered, and this showed obvious effects, with partial response for mRCC and stable disease for BDC. However, the patient also experienced severe adverse events, including hematological and various non-hematological toxicities; the combination therapy was then terminated on day 13 after its initiation. She recovered on day 28 and is alive 3.5 years after the diagnosis. The plasma trough levels of sunitinib and its active metabolite SU12662 on day 13 were 91.5 ng/mL and 19.2 ng/mL, respectively, which were relatively higher than in previous reports. Analysis of her single nucleotide polymorphisms (SNPs) detected TC in ABCB1 3435C/T, TC in 1236C/T and TT in 2677G/T, suggesting a possible TTT haplotype.

CONCLUSION

A rare case of double cancer of mRCC and BDC was treated by combination chemotherapy. Although unknown synergistic mechanisms of these agents may be involved, severe toxicities might be possibly associated with high sunitinib exposure. Further exploration of combination therapy with sunitinib and gemcitabine is required.

NCCTG N0821 (Alliance): a phase II first-line study of pemetrexed, carboplatin, and bevacizumab in elderly patients with advanced nonsquamous non-small-cell lung cancer with good performance status

BACKGROUND

We hypothesized that the combination of bevacizumab, carboplatin, and pemetrexed will be an effective first-line regimen in fit, elderly patients with nonsquamous non-small-cell lung cancer.

METHODS

Treatment-naïve, stage IIIB/IV nonsquamous non-small-cell lung cancer patients more than 70 years old with good performance status (Eastern Cooperative Oncology Group performance status 0-1) and adequate organ function were eligible. Carboplatin area under the curve 6, pemetrexed 500 mg/m, and bevacizumab 15 mg/kg were administered on day 1 of each 21-day cycle (up to six cycles) followed by maintenance pemetrexed and bevacizumab. The primary end point of 6-month progression-free survival rate of at least 70% was assessed using a one-stage binomial design. Quality of life (QOL) questionnaires were administered. Polymorphisms in genes encoding relevant proteins (drug targets, transport, and metabolism proteins) were correlated with treatment outcome.

RESULTS

Fifty-seven eligible patients were enrolled. Median age was 74.5 years. Median treatment cycles received was 6. The most common grade 3 or higher non-hematologic adverse events were fatigue (26%) and hypertension (11%); 16% had grade 4 neutropenia and 6.5% had grade 4 thrombocytopenia. Three patients experienced grade 3/4 hemorrhagic events (one pulmonary, two gastrointestinal). Primary end point of PFS6 was 60% (95% confidence interval [CI]: 45.9-73%). Median PFS was 7.0 months (95% CI: 5.9-10.1), median overall survival was 13.7 months (95% CI: 9.4-16.8). Polymorphic KDR and VEGFA variants correlated with survival and toxicity, respectively. There was no significant change in overall QOL scores over time.

CONCLUSION

This regimen is feasible and did not decrease the QOL in this study population. However, it did not meet the primary efficacy end point.

Management of dose variability and side effects for individualized cancer pharmacotherapy with tyrosine kinase inhibitors

Molecular-targeted therapies with tyrosine kinase inhibitors (TKIs) have provided a major breakthrough in cancer treatment. These agents are given orally and demonstrated to be substrates for drug transporters. In clinical settings, TKIs are mainly used at a fixed dose, but wide interpatient variability has been observed in their pharmacokinetics and/or pharmacodynamics. Genetic polymorphisms of ABC transporters, drug-drug interaction and adherence are among the factors causing such variation. To overcome these problems, therapeutic drug monitoring has been applied in clinical practice for patient care. Skin disorders are frequently observed as adverse drug reactions when using TKIs, and are commonly managed by symptomatic therapy based on clinical experience. Recent studies have provided some insights into the molecular mechanisms underlying skin disorders induced by TKIs. This review article summarizes the accumulated clinical and basic pharmacological evidence of TKIs, focusing on erlotinib, sorafenib and sunitinib.

Finasteride concentrations and prostate cancer risk: results from the Prostate Cancer Prevention Trial

OBJECTIVE

In the Prostate Cancer Prevention Trial (PCPT), finasteride reduced the risk of prostate cancer by 25%, even though high-grade prostate cancer was more common in the finasteride group. However, it remains to be determined whether finasteride concentrations may affect prostate cancer risk. In this study, we examined the association between serum finasteride concentrations and the risk of prostate cancer in the treatment arm of the PCPT and determined factors involved in modifying drug concentrations.

METHODS

Data for this nested case-control study are from the PCPT. Cases were drawn from men with biopsy-proven prostate cancer and matched controls. Finasteride concentrations were measured using a liquid chromatography-mass spectrometry validated assay. The association of serum finasteride concentrations with prostate cancer risk was determined by logistic regression. We also examine whether polymorphisms in the enzyme target and metabolism genes of finasteride are related to drug concentrations using linear regression.

RESULTS AND CONCLUSIONS

Among men with detectable finasteride concentrations, there was no association between finasteride concentrations and prostate cancer risk, low-grade or high-grade, when finasteride concentration was analyzed as a continuous variable or categorized by cutoff points. Since there was no concentration-dependent effect on prostate cancer, any exposure to finasteride intake may reduce prostate cancer risk. Of the twenty-seven SNPs assessed in the enzyme target and metabolism pathway, five SNPs in two genes, CYP3A4 (rs2242480; rs4646437; rs4986910), and CYP3A5 (rs15524; rs776746) were significantly associated with modifying finasteride concentrations. These results suggest that finasteride exposure may reduce prostate cancer risk and finasteride concentrations are affected by genetic variations in genes responsible for altering its metabolism pathway.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00288106.