They were dechorionated, pooled and then weighed by an electronic analytical balance

of Kv1.3. The conductancevoltage curves of activation were fitted by the Boltzmann equation: G=Gmax ~1zexp2} with arylhydroxamate ligand, showed high antitumor activity against several human tumors, nevertheless, no obvious toxicity to normal human cells, is probably as a potential anti-cancer agent against diverse tumors. Cell cycle control is the major regulatory mechanism in the cell growth process. Many cytotoxic agents and/or DNA-damaging agents arrest the cell cycle at the G0/G1, S, or G2/M phase and then induce cell apoptosis. Generally, mammalian cells respond to DNA-damaging agents by activating cell cycle checkpoints, acting by delaying cell cycle progression until errors have been corrected. Sequential activation of cyclin-dependent kinases is involved in cell cycle regulation and deregulated expression of these proteins is commonly observed in cancer cells. In mammalian cells, G2/M transition is controlled by Cdc2 ), which partners with cyclin B1. During G2 phase, the Cdc2/cyclin B1 complex is held in an inactive state by Cdc2 phosphorylation at two negative regulatory sites, threonine-14 and tyrosine-15. At the onset of mitosis, the protein phosphatase Cdc25C activates the Cdc2/cyclin B1 complex by removing the inhibitory phosphate groups from Thr-14 and Tyr-15 on Cdc2. The activity of Cdc25C in turn is tightly regulated by cell cycle-dependent phosphorylation events. The arrest at G2/M is regulated by the 1 Antitumor Mechanism of New Metal Compounds sequential activation and deactivation of Cdc family proteins and cyclin complexes, such as Cdc2/Sodium laureth sulfate site cyclinB complex, which are associated with the entrance into mitosis, thereby regulating the G2/M transition. The phosphorylation of Tyr-15 of Cdc2 suppresses activity of Cdc2/cyclinB1 kinase complex. Dephosphorylation of Tyr15 PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/19631915 of Cdc2 is catalyzed by Cdc25C phosphatases, and this reaction is believed to be the rate-limited step for the entrance into mitosis. G2/M cell cycle arrest mediated the phosphorylation of its downstream effector Chk2. Cdc25C is a phosphatase, its function is negatively regulated by p-Chk2induced phosphorylation at Ser-216 residue during S phase and DNA damage. Cell cycle progression is also regulated by the relative balance between the cellular concentrations of cyclin-dependent kinase inhibitors, such as members of the cyclin-dependent kinaseinteracting protein/cyclin-dependent kinase inhibitory protein and inhibitor of cyclin-dependent kinase families, and that of cyclinCDK complexes. The Cip/Kip family, including p21/WAF1 and p27/KIP, binds to cyclin-CDK complexes and prevents the kinase activation, subsequently blocks the progression of the cell cycle at the G2/M phases. Cdc2 is inhibited simultaneously by four transcriptional targets; those are p53, Gadd45, p21, and 14-3-3s. P53 is a transcription factor that up-regulating a number of important cell cycle-modulating genes such as p21. Part of the mechanism by which p53 blocks cells at the G2 checkpoint involves inhibition of Cdc2, the cyclin-dependent kinase required to enter mitosis. In the PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/19632179 absence of Cdc2 dephosphorylation by Cdc25C, and also the direct phosphorylation of cyclinB, the accumulation of Cdc2/cyclinB in the nucleus is prevented and entrance into mitosis is stalled. In addition to controlling the cell cycle to regulate the cell growth process, several therapeutic and chemopreventive agents could eliminate cancerous cells by inducing apoptosis. Cell apoptosis is an intracellular suicide pr