Cancer chemotherapy and pharmacology
-
Cancer Chemother. Pharmacol. · Apr 2004
Systemic and tumor disposition of platinum after administration of cisplatin or STEALTH liposomal-cisplatin formulations (SPI-077 and SPI-077 B103) in a preclinical tumor model of melanoma.
SPI-077 and SPI-077 B103 are formulations of cisplatin encapsulated in pegylated STEALTH liposomes that accumulate in tumors. However, the extent to which active platinum (Pt) is released from the liposome is unknown. Thus, we evaluated the disposition of encapsulated and released Pt in plasma and tumors after administration of STEALTH liposomal and nonliposomal cisplatin. ⋯ This study suggests that more SPI-077 and SPI-077 B103 distribute into tumors, but release less Pt into tumor ECF, and form fewer Pt-DNA adducts than does cisplatin.
-
Cancer Chemother. Pharmacol. · Mar 2004
Thrombospondin-1 plus irinotecan: a novel antiangiogenic-chemotherapeutic combination that inhibits the growth of advanced human colon tumor xenografts in mice.
Chemotherapy for the treatment of advanced or metastatic colon cancer, utilizing agents such as 5-fluorouracil (5-FU) and irinotecan (CPT-11), produce a 5-year survival of about 10%. Thus, the identification of new, effective, therapeutic regimens to treat this disease remains critically important. To this end, selected antiangiogenic agents, compounds that inhibit neovascularization, have been shown to produce a modest tumor growth-inhibitory effect with little systemic toxicity. ⋯ When TSP-1 was combined with CPT-11, a significant ( P< or = 0.05) inhibition of tumor growth also was observed (T/C < or = 0.17, range 0.11-0.20). Importantly, this enhanced tumor growth inhibition was obtained without significant toxicity. The therapeutic implications of these findings are discussed.
-
Cancer Chemother. Pharmacol. · Feb 2004
The influence of the P-glycoprotein inhibitor zosuquidar trihydrochloride (LY335979) on the brain penetration of paclitaxel in mice.
We determined the effect of zosuquidar.3HCl, an inhibitor of P-gp, on the penetration of the anticancer drug paclitaxel into the brain. Zosuquidar.3HCl was administered orally at 25 and 80 mg/kg 1 h before i.v. paclitaxel and i.v. at 20 mg/kg 10 min and 1 h before paclitaxel. The concentrations of paclitaxel in plasma and tissues and of zosuquidar.3HCl in plasma were quantified by high-performance liquid chromatography. ⋯ When zosuquidar.3HCl was administered i.v. 10 min before paclitaxel, the paclitaxel levels in the brain of wild-type mice increased by 5.6-fold, whereas the increase was only 2.1-fold when zosuquidar.3HCl was administered 1 h before paclitaxel. This suggests that the inhibition of P-gp at the blood-brain barrier by zosuquidar.3HCl is rapidly reversible and that the concentrations of zosuquidar.3HCl in the plasma have already declined to levels insufficient to inhibit P-gp at the blood-brain barrier. In conclusion, zosuquidar.3HCl is only moderately active as an inhibitor of P-gp at the blood-brain barrier.
-
Cancer Chemother. Pharmacol. · Jan 2004
Clinical TrialA phase II study of intravenous exatecan mesylate (DX-8951f) administered daily for 5 days every 3 weeks to patients with advanced ovarian, tubal or peritoneal cancer resistant to platinum, taxane and topotecan.
DX-8951f is a water-soluble camptothecin derivative with greater in vivo and in vitro activity than topotecan or irinotecan. The objectives of this phase II study were to determine the antitumor activity, safety and pharmacokinetic profile of DX-8951f administered intravenously for five consecutive days, every 3 weeks in patients with advanced ovarian, tubal and peritoneal cancer resistant to platinum, taxane and topotecan. ⋯ DX-8951f administered parenterally as a single agent daily at a dose of either 0.5 or 0.3 mg/m(2) per day for 5 days is feasible in patients with advanced ovarian, tubal and peritoneal cancer resistant to platinum, taxane and topotecan. Although no responses were observed, a significant number of patients had stable disease with a decrease in CA-125 levels. In this heavily pretreated population, DX-8951f has clinically relevant hematologic and gastrointestinal toxicities in about 25% of patients. DX-8951 appeared to have linear pharmacokinetic characteristics on the basis of multiple administrations.
-
Cancer Chemother. Pharmacol. · Jan 2004
Evaluation of the antiangiogenic effect of Taxol in a human epithelial ovarian carcinoma cell line.
Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) are major ligands for the endothelium-specific tyrosine kinase receptor Tie-2 and are important regulators of endothelial cell survival. In the presence of vascular endothelial growth factor (VEGF), vessel destabilization by Ang-2 has been hypothesized to induce an angiogenic response, but in the absence of VEGF, Ang-2 leads to vessel regression. In the present study, a human ovarian cancer cell line was used to investigate the possibility that Taxol might affect the expression of Ang-1, Ang-2, and VEGF. ⋯ Our results show that exposure of ovarian cancer cells to a low concentration of Taxol may inhibit the initiating event in angiogenesis, namely, vascular regression. This information might be valuable in the development of new therapeutic interventions for epithelial ovarian cancer.