10-Propargylaminopterin and alkyl homologues of methotrexate as inhibitors of folate metabolism

Acetylenic antifolates as anticancer agents

Folates are crucial cofactors involved in the de novo generation of purine and deoxythymidine monophosphate, which are essential for DNA synthesis. Antifolates are structural analogues of folate derivatives that act as inhibitors of folate-dependent enzymes and constitute the oldest antimetabolite class of anticancer agents. This review focuses on antifolates with remarkable anticancer activities that include a terminal alkyne function in their molecular structure. The properties of CB3717, a tremendous inhibitor of thymidylate synthase, are described, and the development of raltitrexed and pralatrexate, a dihydrofolate reductase inhibitor approved by the U.S. Food and Drug Administration (FDA) as the first drug for the treatment of relapsed and refractory peripheral T cell lymphoma are presented.

A novel thiazolidine compound induces caspase-9 dependent apoptosis in cancer cells

The forward chemogenomics strategy allowed us to identify a potent cytotoxic thiazolidine compound as an apoptosis-inducing agent. Chemical structures were designed around a thiazolidine ring, a structure already noted for its anticancer properties. Initially, we evaluated these novel compounds on liver, breast, colon and endometrial cancer cell lines. The compound 3 (ALC67) showed the strongest cytotoxic activity (IC(50) ∼5 μM). Cell cycle analysis with ALC67 on liver cells revealed SubG1/G1 arrest bearing apoptosis. Furthermore we demonstrated that cytotoxicity of this compound was due to the activation of caspase-9 involved apoptotic pathway, which is death receptor independent.

Pharmacokinetics of methotrexate and 7-hydroxy-methotrexate in plasma and bone marrow of children receiving low-dose oral methotrexate

The absorption, distribution, and elimination kinetics of low-dose p.o. methotrexate (MTX) were repeatedly studied in 19 children during maintenance treatment of childhood acute lymphoblastic leukemia. Plasma concentrations, urinary elimination, and bone marrow concentrations of MTX and 7-hydroxymethotrexate (7-OH-MTX) were monitored during 24 h following a routine p.o. dose (30 mg/m2) using high-pressure liquid chromatography. Significant interindividual variability was found in time to peak concentration (30-180 min), peak concentration (0.41-2.77 microM), and to a lesser extent the half-lives (t1/2 alpha: 32.8-86.1 min; t1/2 beta: 43.6-350.0 min; t1/2 absorption: 25.2-60.3 min) and plasma area under the concentration-time curve from zero to infinity (195.6-818.5 microM.min). Significant amounts of 7-OH-MTX were detected in plasma, with a mean area under the concentration-time curve from zero to infinity of 208 microM.min compared with 365.6 microM.min for MTX. High concentrations of 7-OH-MTX were present in bone marrow 24 h after oral MTX (15/19 patients) and were at least five fold those in plasma and three fold the concentration of MTX in bone marrow. In four patients occasionally neither MTX nor metabolite could be detected. Repeated examination of these pharmacokinetic parameters in plasma and bone marrow showed that the intraindividual variability was small.