Assessment of efficacy of postinfusion tubing flushing in reducing risk of cytotoxic contamination.

PURPOSE: Infusion of cytotoxic drugs carries the risk of occupational exposure of healthcare workers. Since disconnecting an infusion line is a source of contamination, flushing of tubing after infusion of cytotoxic agents is recommended, but the optimal volume of rinsing solution is unknown. The objective of this study was to assess whether postinfusion line flushing completely eliminates cytotoxics. METHODS: Infusions were simulated with 3 cytotoxics (gemcitabine, cytarabine, and paclitaxel) diluted in 5% dextrose injection or 0.9% sodium chloride injection in 250-mL infusion bags. Infusion lines were flushed using 5% dextrose injection or 0.9% sodium chloride solution at 2 different flow rates. The remaining concentration of cytotoxics in the infusion line was measured by a validated high-performance liquid chromatography (HPLC) method after passage of every 10 mL of flushing volume until a total of 100 mL had been flushed through. RESULTS: All cytotoxics remained detectable even after line flushing with 80 mL of flushing solution (a volume 3-fold greater than the dead space volume within the infusion set). Gemcitabine and cytarabine were still quantifiable via HPLC even after flushing with 100 mL of solution. Efficacy of flushing was influenced by the lipophilicity of drugs but not by either the flushing solvent used or the flushing flow rate. After 2-fold dead space volume flushing, the estimated amount of drug remaining in the infusion set was within 0.19% to 0.56% of the prescribed dose for all 3 cytotoxics evaluated. CONCLUSION: Complete elimination of cytotoxics from an infusion line is an unrealistic objective. Two-fold dead space volume flushing could be considered optimal in terms of administered dose but not from an environmental contamination point of view. Even when flushed, the infusion set should still be considered a source of cytotoxic contamination.

Irreversible hepatotoxicity after administration of trabectedin to a pleiomorphic sarcoma patient with a rare ABCC2 polymorphism: a case report.

We describe here the case of a 60-year old male patient treated for an extensive local progression of a pleiomorphic sarcoma on the right tibial crest with second-line trabectedin. Two cycles were administrated before a major liver toxicity was retrieved, with both cytolytic and cholestatic hepatitis quickly associated with irreversible jaundice. The radiological, histological, chemistry and pharmacogenetic investigations led us to diagnose chronic hepatobiliary toxicity with portal fibrosis, cholangiolitis damages and chronic hepatopathy. The patient had a deficient variant genotype of ABCC2 (c.-24TT, c.4488CT and c.4544GA), which has been suggested to play a role in excretion of toxic metabolites of trabectedin. This case report is, to our knowledge, the first description of trabectedin's irreversible liver toxicity in a human patient. Supported by a thorough review of the literature, this hepatitis is thought to have resulted from a multihit process involving genetic variants of ABC proteins and comedication.

Gene expression profiling on pre- and post-erlotinib tumors from patients with head and neck squamous cell carcinoma.

BACKGROUND: The purpose of our work was to identify genomic predictive markers of erlotinib response in patients with head and neck squamous cell carcinoma (HNSCC). METHODS: Tumor tissue biopsies were collected before and after treatment for 39 patients. We analyzed genomic expression of the tumors using microarrays to (1) identify genes differentially expressed in baseline samples in patients who were responders vs nonresponders, (2) characterize erlotinib's effect on gene expression, and (3) identify the pharmacodynamic marker of erlotinib. RESULTS: Gene expression profiles found no statistically significant differentially expressed genes between responders and nonresponders. An exploratory analysis by combining statistical criteria allowed us to identify genes differentially expressed in nonresponders compared to responders and genes whose expression was modified during erlotinib treatment. Finally, the search of pharmacodynamic markers identified cyclin-dependent kinase 2-interacting protein (CINP) as a potential marker of erlotinib efficacy because its expression decreased only in patients who were responders to the treatment. CONCLUSION: This study provides candidate genes potentially involved in erlotinib response in HNSCC.

Ovarian ascites-derived Hospicells promote angiogenesis via activation of macrophages.

Within the microenvironment, Carcinoma-associated mesenchymal stem cells (Hospicells) are able to influence ovarian tumor development via, among others, the facilitation of angiogenesis in the tumor site allowing an accelerated tumor growth. We demonstrate the presence of a chemotactism between endothelial cells and Hospicells, and a cell line specific increased secretion of pro-angiogenic cytokines such as IL-6, IL-8 and VEGF from ovarian adenocarcinoma cells. Hospicells are also able to attract and activate macrophages to a M2 phenotype and allow them to secrete a huge quantity of pro-angiogenic cytokines, favorable to tumor progression of all the associated ovarian adenocarcinoma cells tested.

Multifactorial pharmacogenetic analysis in colorectal cancer patients receiving 5-fluorouracil-based therapy together with cetuximab-irinotecan.

AIM: To examine the predictive value of gene polymorphisms potentially linked to toxicity, clinical response, time to progression and overall survival, following cetuximab-tegafur-uracil (UFT)-irinotecan therapy. METHODS: Fifty-two patients with advanced colorectal cancer were enrolled in an ancillary pharmacogenetic study of the phase II CETUFTIRI trial. Treatment consisted of 21 day cycles of cetuximab (day 1-day 8-day 15, 250 mg m(-2) week(-1) following a 400 mg m(-2) initial dose) together with irinotecan (day 1, 250 mg m(-2)) and UFT-folinic acid (days 1-14, 250 mg m(-2) day(-1) UFT, 90 mg day(-1) folinic acid). Analysed gene polymorphisms (blood DNA) were as follows: EGFR (CA repeats in intron 1, -216G>T, -191C>A), EGF (61A>G), FCGR2A (131Arg>His), FCGR3A (158Phe>Val), UDP-glycosyltransferase1-polypeptide A1 (TA repeats), TYMS (28 bp repeats, including the G>C mutation on the 3R allele, 6 bp deletion in 3' UTR) and MTHFR (677C>T, 1298A>C). RESULTS: Maximum toxicity grade was linked to EGFR-191C>A polymorphism, with 71.1% grade 3-4 toxicity in CC patients vs. 28.6% in other patients (P= 0.010). A tendency to a better response was observed in patients bearing the TYMS 3RG allele (P= 0.029) and those bearing the FCGR3A 158Val genotype (P= 0.020). The greater the score of favourable TYMS and FCGR3A genotypes, the better the response rate (P= 0.009) and the longer the overall survival (P= 0.007). In multivariate analysis, the score of favourable genotypes was a stronger survival predictor than the performance status. CONCLUSIONS: Present data suggest the importance of FCGR3A 158Phe>Val and TYMS 5' UTR polymorphisms in responsiveness and survival of patients receiving cetuximab-fluoropyrimidine-based therapy.

Unexpected high levels of vorinostat when combined with vinorelbine in patients with advanced cancer.

BACKGROUND: This study was a multi-centre, dose-escalation trial in patients with advanced cancers. Primary objective was to determine maximum tolerated dose (MTD) of vorinostat, a competitive inhibitor of histone deacetylase (HDAC), in combination with vinorelbine. Secondary aims were to determine (1) corresponding pharmacokinetics, (2) safety of this regimen, and (3) impact of UGT1A1 and 2B17 polymorphisms on vorinostat pharmacokinetics. METHODS: Starting dose of once daily oral vorinostat was 200 mg for 7 days every 21 days in combination with a 20-min intraveinous weekly infusion of vinorelbine 25 mg/m2, starting 4 hours after the first vorinostat dose. During cycle 1, blood samples were collected at day 1 for vorinostat and at days 1 and 8 for vinorelbine for pharmacokinetic evaluation. RESULTS: Seven patients were included. Most of adverse events observed were mild (grades 0-2) and reversible after treatment discontinuation (hemotological toxicity, asthenia, diarrhea, dyspnea, fever, hyperglycemia and nausea). Two patients had a dose limiting toxicity at the first dose level that consisted of grade 3 hyperglycemia and vinorelbine administration was delayed. The first dose-level was considered as the MDT and therefore dose escalation was stopped. Mean vorinostat plasma AUC was higher than reported previously at a similar dose when used as single agent or in combination with other cytotoxics. There was no obvious vinorelbine-vorinostat interaction nor any correlation with UGT1A1 or 2B17 polymorphisms. CONCLUSION: MDT of the combination was 200 mg oral vorinostat for 7 days in combination with 25 mg/m2 weekly vinorelbine. Severity of hyperglycemia was most likely related to unexpected high vorinostat exposures.

Population analysis of erlotinib in adults and children reveals pharmacokinetic characteristics as the main factor explaining tolerance particularities in children.

PURPOSE: The aim of this pharmacokinetic-pharmacodynamic (PK-PD) analysis was to evaluate the pharmacologic characteristics of erlotinib and its main metabolite (OSI-420) in pediatric patients compared with those in adult patients. EXPERIMENTAL DESIGN: Plasma concentrations of erlotinib and OSI-420 of 46 children with malignant brain tumors included in a phase I study and 42 adults with head and neck carcinoma were analyzed by a population-pharmacokinetic method (NONMEM). The effect of several covariates and single nucleotide polymorphisms (SNP) in ABCB1, ABCG2, and CYP3A5 on pharmacokinetic parameters was evaluated. PK/PD relationships between plasma drug exposure Area Under the Curve (AUC) at day 1 and skin toxicity were studied in children and compared with the relationship observed in adults. RESULTS: A significant difference in erlotinib clearance (P = 0.0001), when expressed in L·h(-1)·kg(-1), was observed between children and adults with mean values of 0.146 and 0.095, respectively (mean difference = 0.051 L·h(-1)·kg(-1), SD = 0.0594). However, a common covariate model was obtained describing erlotinib clearance according to body weight, alanine aminotransferase, ABCB1, and CYP3A5 polymorphisms (2677G > T/A and 6986G > A) for both children and adult patients. The PK-PD relationship was very consistent between the children and adult groups with risk of skin toxicity rising with increasing erlotinib AUC. CONCLUSIONS: The nonlinear population approach applied to pharmacokinetic data combined with a pharmacokinetic-pharmacodynamic analysis revealed that the higher recommended dose in children (125 mg/m(2)/day) compared with adults (90 mg/m(2)/day) is mainly due to pharmacokinetic rather than pharmacodynamic particularities.

Hospicells (ascites-derived stromal cells) promote tumorigenicity and angiogenesis.

The microenvironment is known to play a dominant role in cancer progression. Cells closely associated with tumoral cells, named hospicells, have been recently isolated from the ascites of ovarian cancer patients. Whilst these cells present no specific markers from known cell lineages, they do share some homology with bone marrow-derived or adipose tissue-derived human mesenchymal stem cells (CD9, CD10, CD29, CD146, CD166, HLA-1). We studied the role of hospicells in ovarian carcinoma progression. In vitro, these cells had no effect on the growth of human ovarian carcinoma cell lines OVCAR-3, SKOV-1 and IGROV-1. In vivo, their co-injection with adenocarcinoma cells enhanced tumor growth whatever the tumor model used (subcutaneous and intraperitoneally established xenografts in athymic mice). In addition, their injection increased the development of ascites in tumor-bearing mice. Fluorescent macroscopy revealed an association between hospicells and ovarian adenocarcinoma cells within the tumor mass. Tumors obtained by coinjection of hospicells and human ovarian adenocarcinoma cells presented an increased microvascularization indicating that the hospicells could promote tumorigenicity of ovarian tumor cells in vivovia their action on angiogenesis. This effect on angiogenesis could be attributed to the increased HIF1alpha and VEGF expression associated with the presence of the hospicells. Collectively, these data indicate a role for these ascite-derived stromal cells in promoting tumor growth by increasing angiogenesis.

Population pharmacokinetics of erlotinib and its pharmacokinetic/pharmacodynamic relationships in head and neck squamous cell carcinoma.

UNLABELLED: A clinical study was conducted to determine the safety and efficacy of neoadjuvant erlotinib treatment in patients with head and neck squamous cell carcinoma [Thomas F, Rochaix P, Benlyazid A, et al. Pilot study of neoadjuvant treatment with erlotinib in non-metastatic head and neck squamous cell carcinoma. Clin Cancer Res 2007;13:7086-92]. The aim of the present analysis was to explore the impact of several covariates on the pharmacokinetics of erlotinib and its main metabolite (OSI-420) and to determine PK/PD relationships. PATIENTS AND METHODS: Plasma concentrations of erlotinib and OSI-420 of 42 patients were analysed using the NONMEM program to evaluate the impact of patients' covariates on erlotinib pharmacokinetics. The presence of single nucleotide polymorphisms (SNP) in ABCB1 (2677G>T/A and 3435C>T), ABCG2 (421C>A) and CYP3A5 (6986G>A) was investigated. Pharmacokinetic/pharmacodynamic relationships between plasma drug exposure (AUC) and early drug response or toxicity were also studied. RESULTS: The covariates retained to predict erlotinib clearance were ALAT (alanine amino transferase), age and ABCG2 polymorphism. A significant link between drug exposure and the grade of skin rash was observed but early response to treatment was not correlated to the erlotinib AUC. CONCLUSIONS: Erlotinib treatment may present criteria justifying dose individualisation but further studies, including more patients, are necessary to define the modalities of this adaptation.

In vivo and in vitro antitumor activity of oxaliplatin in combination with cetuximab in human colorectal tumor cell lines expressing different level of EGFR.

This study aimed to assess the effect of cetuximab (C225, Erbitux, a chimeric anti-epidermal growth factor receptor (EGFR) monoclonal antibody) in combination with oxaliplatin in vitro and in vivo on four colon cancer cell lines (HCT-8; HT-29, SW620, HCT-116) expressing different levels of EGFR. In vitro, cetuximab combined with oxaliplatin significantly decreased the IC50 values of oxaliplatin in HCT-8 (EGF-R moderate) and HT-29 (EGF-R weak) cell lines, while SW620 (EGF-R negative) and HCT-116 (EGFR strong) cell lines remained unresponsive. This combination was synergistic in HCT-8 and HT-29 cell lines while cetuximab induced no major modification of the IC50 of oxaliplatin in HCT-116 or SW620 cell lines. We then determined the effect of cetuximab on the EGF-induced EGFR phosphorylation and we highlight a correlation between the basal level of phospho-EGFR and the response to the combination. In vivo, the combination of cetuximab plus oxaliplatin significantly inhibited tumor growth of HCT-8 and HT-29 (tumor delay or Td = 21.6+/-2.9 and 18.0+/-2.9 days respectively, synergistic effect) compared to either oxaliplatin (Td=12.6+/-2.3 and 14.4+/-3.2 days respectively) or cetuximab (Td=13.4+/-2.9 and 14.5+/-2.4 days, respectively) alone in xenograft models. The combination had no effect on HCT-116 and SW-620 cell lines. The observed responses are strictly dependent on the cell type, and are not correlated with the level of EGFR expression but related to the basal level of phospho-EGFR. This study provides promising preclinical results for a possible clinical investigation of the combination of oxaliplatin plus cetuximab in chemorefractory colorectal tumors.

Dexamethasone as a probe for docetaxel clearance.

PURPOSE: A pilot study was conducted in 23 patients in order to assess the correlation between docetaxel clearance (CL) and pharmacokinetics of dexamethasone. Dexamethasone is mainly 6-beta hydroxylated by CYP3A4, and is regularly used as standard docetaxel premedication. Genotyping of known functional single nucleotide polymorphism (SNP) of CYP3A5 (G22893A) and mdr-1 (G2677T, G2677A, and C3435T) have been performed in order to tentatively correlate genotype with docetaxel and dexamethasone pharmacokinetics. PATIENTS AND METHODS: To be eligible for this study, patients were required to have a solid malignancy for which docetaxel was indicated. A population pharmacokinetic approach was used to determine individual pharmacokinetic parameters of both docetaxel and dexamethasone by Bayesian analysis, and to screen relationships between docetaxel CL and patients' demographic, phenotype and genotype covariates. RESULTS: Three different pharmacokinetic parameters of dexamethasone were significantly correlated with docetaxel CL: dexamethasone plasma clearance (DPC) that ranged between 7.7 and 27.2 l/h, urinary amount of 6beta-hydroxydexamethasone, and the ratio between urinary amount of 6beta-hydroxydexamethasone and unchanged dexamethasone. The best covariate model was docetaxel CL (l/h) = 356 x fu(alpha1-AG) x (1-0.17 x HPMT)(1+0.126 x DPC) where fu(alpha1-AG) is the unbound plasma fraction of docetaxel calculated from alpha1-acid glycoprotein plasma level, and HPMT is hepatic metastasis coded as 1 if present or 0 if absent. No significant difference in docetaxel CL was observed between the several genotypes. CONCLUSIONS: Dexamethasone may be used as a probe to predict docetaxel clearances, hence reducing interindividual variability.

Contribution of apoptosis in the cytotoxicity of the oxaliplatin-irinotecan combination in the HT29 human colon adenocarcinoma cell line.

Interactions between the topoisomerase I inhibitor irinotecan (CPT-11) and the platinum derivative oxaliplatin (L-OHP) were investigated in HT29 colon cancer cell line. Synergism was observed when cells were simultaneously exposed to drugs or when cells were first exposed to CPT-11. Flow cytometric studies showed a G(2)/M accumulation when cells were exposed to the simultaneous and CPT-11-->L-OHP combinations whereas a persistent S phase delay was observed when cells were first exposed to L-OHP. We characterised the cytotoxic effect by assessing the induction of apoptosis. Irinotecan induced substantial DEVDase activity and poly(ADP-ribose) polymerase cleavage while this activity was moderate and delayed after exposure to L-OHP. Combination experiments showed a sequence-dependent onset of apoptosis, the CPT-11-->L-OHP schedule being the earliest and the most effective; on the other hand the apoptotic signaling generated by CPT-11 was partly inhibited in the simultaneous combination and in the L-OHP-->CPT-11 sequence. Cell death studies using a dual staining technique showed a shift from apoptosis to necrosis when combining these drugs at high concentrations. Synergistic interactions observed using CPT-11 before L-OHP may be linked to an early apoptotic signaling while the L-OHP-induced S phase block could account for the observed additive effect in the reverse sequence. An additional phenomenon might work towards synergism for the simultaneous combination.