Mitotane has an estrogenic effect on sex hormone-binding globulin and corticosteroid-binding globulin in humans.

CONTEXT: Side effects of mitotane (o,p'-DDD) have suggested estrogenic effects. OBJECTIVE: The objective of the study was to explore o,p'-DDD potential estrogenic effect on SHBG and corticosteroid-binding globulin (CBG). DESIGN: Human hepatoma cell lines (HepG2), lacking estrogen receptor (ER)-alpha, and Hep89, stably transfected by ERalpha, were used. SETTING: The study was conducted at an academic research laboratory and medical center. PATIENTS AND OTHER PARTICIPANTS: The study included 10 male patients with recurrent adrenal carcinoma, receiving mitotane (4-6.5 g daily) for more than 6 months. MAIN OUTCOME MEASURES: The main outcome measures were SHBG/CBG mRNA levels measured by real-time PCR, culture medium SHBG/CBG concentrations measured by specific immunoassays, and transient transfection experiments with human SHBG proximal promoter reporter constructs. RESULTS: Increased serum SHBG and CBG concentrations, which exceeded normal male limits, were observed in most mitotane-treated patients. In the HepG2 cell line, 17beta-estradiol (E2) or o,p'-DDD treatment had no effect on mRNA or SHBG/CBG concentrations. In contrast, in the Hep89 cell line, E2 increased concentrations of SHBG (r = 0.44, P < 0.0001) and CBG (r = 0.585, P < 0.0001) secreted into culture media in a dose-dependent manner. o,p'-DDD significantly increased SHBG (150% vs. control, P < 0.05) and CBG (184% vs. control, P < 0.05) production by Hep89 cells, at a concentration of 2 x 10(-5) m. Transient transfection experiments in Hep89 cells showed that E2 or o,p'-DDD treatment did not increase the transcriptional activity of the minimal proximal promoter of human SHBG gene. CONCLUSIONS: Mitotane increased SHBG/CBG gene expression and liver production by mechanisms requiring the presence of ERalpha.

Pharmacokinetic profile of cetuximab (Erbitux) alone and in combination with irinotecan in patients with advanced EGFR-positive adenocarcinoma.

This trial assessed pharmacokinetic interactions between cetuximab and irinotecan. Patients were placed in either in group A (irinotecan 350 mg/m2/3 weeks and 400 mg/m2 cetuximab at week 2 then 250 mg/m2/week) or group B (cetuximab weekly starting week 1 then irinotecan starting week 4). Patient plasma or serum samples from each treatment arm were analysed using HPLC and ELISA. Among 14 patients, compartmental model showed no significant differences in mean plasma AUC at week 1 versus week 4 for irinotecan (44,388 versus 39,800 microg/ml/h) and cetuximab (20,441 versus 23,363 microg/ml/h), respectively. Half-lifes (standard deviations) for irinotecan were 16.02 (+/-8.41) h at week 1 and 13.99 (+/-2.14) h at week 4, and for cetuximab 106 (+/-32) at week 3 and 111 (+/-30) h at week 4. Mean concentration-versus-time profiles either alone or in combination were superimposable for cetuximab and irinotecan. From this study, we conclude that there is no evidence of pharmacokinetic interaction between irinotecan and cetuximab.

Pharmacokinetic advantage of intra-arterial hepatic oxaliplatin administration: comparative results with cisplatin using a rabbit VX2 tumor model.

The aim of this study was to compare intra-arterial hepatic administration (IAH) versus i.v. administration of oxaliplatin and cisplatin in a VX2 tumor model in rabbits. VX2 tumors were implanted in the livers of White New Zealand female rabbits and 2 weeks later they received either cisplatin (4 mg/kg) or oxaliplatin (6 mg/kg) administered by IAH or i.v. Platinum pharmacokinetic parameters were measured by atomic absorption spectrometry at baseline, 2, 5 10, 20, 40 and 60 min, and then at 2, 4, 6 and 24 h after drug administration. Animals were sacrificed 24 h after drug administration to measure platinum concentrations in various tissues. After IAH oxaliplatin administration, we observed a significant decrease for total and filterable platinum in the Cmax compared with i.v. administration (12.4 versus 18.2 microg/l; p=0.02 and 11.2 versus 17.3 microg/l; p=0.02, respectively). Significant differences in various tissue concentrations were reported when comparing IAH and i.v. administration of oxaliplatin with IAH administration offering an advantage over i.v. administration. No differences in pharmacokinetic parameters or platinum tissue accumulation were apparent between the IAH and i.v. administration with cisplatin. We conclude that there is a significant pharmacokinetic advantage to using oxaliplatin for locoregional IAH chemotherapy compared with i.v. administration.