Imidazo[2,1-b]thiazole guanylhydrazones as RSK2 inhibitors.

The activity of a series of imidazo[2,1-b]thiazole guanylhydrazones as inhibitors of p90 ribosomal S6 kinase 2 (RSK2) is described. It was found that a small subset of compounds show both potent inhibition of RSK2 kinase activity and tumor cell growth in vitro. Detailed study of one of the most active compounds indicates a high degree of selectivity for inhibition of RSK2 compared to a spectrum of other related kinases.

Cellular inhibition of checkpoint kinase 2 (Chk2) and potentiation of camptothecins and radiation by the novel Chk2 inhibitor PV1019 [7-nitro-1H-indole-2-carboxylic acid {4-[1-(guanidinohydrazone)-ethyl]-phenyl}-amide].

Chk2 is a checkpoint kinase involved in the ataxia telangiectasia mutated pathway, which is activated by genomic instability and DNA damage, leading to either cell death (apoptosis) or cell cycle arrest. Chk2 provides an unexplored therapeutic target against cancer cells. We recently reported 4,4'-diacetyldiphenylurea-bis(guanylhydrazone) (NSC 109555) as a novel chemotype Chk2 inhibitor.

Gene expression-signature of belinostat in cell lines is specific for histone deacetylase inhibitor treatment, with a corresponding signature in xenografts.

Belinostat is a hydroxamate-type histone deactylase inhibitor (HDACi), which has recently entered phase I and II clinical trials. Microarray-based analysis of belinostat-treated cell lines showed an impact on genes associated with the G2/M phase of the cell cycle and downregulation of the aurora kinase pathway. Expression of 25 dysregulated genes was measured in eight differentially sensitive cell lines using a novel high-throughput assay that combines multiplex reverse transcriptase-PCR and fluorescence capillary electrophoresis.

Identification of a Bis-guanylhydrazone [4,4'-Diacetyldiphenylurea-bis(guanylhydrazone); NSC 109555] as a novel chemotype for inhibition of Chk2 kinase.

Chk2 is a protein kinase involved in the ATM-dependent checkpoint pathway (http://discover.nci.nih.

Altered expression of neuronal nitric oxide synthase in the duodenum longitudinal muscle-myenteric plexus of obesity induced diabetes mouse: implications on enteric neurodegeneration.

Type 2 diabetes caused by obesity shows autonomic neuropathy. Molecular mechanism involved in enteric neurodegeneration is not clear. Neuronal nitric oxide synthase (nNOS) is one of the important agents involved in gastrointestinal function.

7-hydroxystaurosporine (UCN-01) inhibition of Akt Thr308 but not Ser473 phosphorylation: a basis for decreased insulin-stimulated glucose transport.

7-hydroxystaurosporine (UCN-01) infused for 72 hours by continuous i.v. infusion induced insulin resistance during phase I clinical trials.

Perifosine, a novel alkylphospholipid, inhibits protein kinase B activation.

Perifosine is a novel p.o. bioavailable alkylphospholipid.

Evidence for the existence of a new receptor for CGRP, which is not CRLR.

Receptors for calcitonin gene-related peptide (CGRP), a neuropeptide known to be the most potent vasodilator, are abundantly expressed in cerebellum. A monoclonal antibody to cerebellar CGRP receptors specifically detects a 66 kDa protein from rat cerebellum and other rat and human tissues, but not from SK-N-MC cells which express calcitonin receptor-like receptor (CRLR), a recently described component of CGRP receptors. In contrast, mRNA expression for CRLR was abundant in SK-N-MC cells, but it was undetectable in rat cerebellum.

Expression and regulation of calcitonin gene-related Peptide receptor in rat placentas.

Calcitonin gene-related peptide (CGRP), one of the most potent vasodilators known, exerts its biological action by interacting with its receptors. Recent reports suggest the existence of two types of CGRP receptors, CGRP-A and CGRP-B. The current study was designed to examine whether CGRP-B receptors are present in the rat placenta, and if they are, whether they are modulated by gestational age and by sex-steroid hormones.

Calcitonin gene-related peptide in pregnancy and its emerging receptor heterogeneity.

Calcitonin gene-related peptide (CGRP) is the most potent vasodilator, and there is a growing body of evidence that this peptide might have multiple other functions. During pregnancy, circulating CGRP levels in rats increase up to the time of delivery, followed by a sharp decline at term and postpartum. In addition, the sensitivity of various vascular beds to CGRP in rats appears to increase with advancing pregnancy.