Synthesis and biological activity of selective pipecolic acid-based TNF-alpha converting enzyme (TACE) inhibitors

A series of novel, selective TNF-alpha converting enzyme inhibitors based on 4-hydroxy and 5-hydroxy pipecolate hydroxamic acid scaffolds is described. The potency and selectivity of TACE inhibition is dramatically influenced by the nature of the sulfonamide group which interacts with the S1' site of the enzyme. Substituted 4-benzyloxybenzenesulfonamides exhibit excellent TACE potency with >100x selectivity over inhibition of matrix metalloprotease-1 (MMP-1). Alkyl substituents on the ortho position of the benzyl ether moiety give the most potent inhibition of TNF-alpha release in LPS-treated human whole blood.     

Oxygen and nitrate-dependent regulation of <Emphasis Type="Italic">dmsABC</Emphasis> operon expression in <Emphasis Type="Italic">Escherichia coli</Emphasis>: sites for Fnr and NarL protein interactions

Background  

Escherichia coli can respire anaerobically using dimethyl sulfoxide (DMSO) or trimethylamine-N-oxide (TMAO) as the terminal electron acceptor for anaerobic energy generation. Expression of the dmsABC genes that encode the membrane-associated DMSO/TMAO reductase is positively regulated during anaerobic conditions by the Fnr protein and negatively regulated by the NarL protein when nitrate is present.     

Synthesis and biological activity of piperazine-based dual MMP-13 and TNF-alpha converting enzyme inhibitors

A series of novel MMP-13 and TNF-alpha converting enzyme inhibitors based on piperazine 2-hydroxamic acid scaffolds are described. The TACE, MMP-1 and MMP-13 activity of these inhibitors as well as the effect of substitution of the piperazine nitrogen and the P-1' benzyloxy tailpiece is discussed. Moderate in vivo activity is observed with several members of this group.     

The joys of HexNAc. The synthesis and function of N-andO-glycan branches

This review covers discoveries made over the past 30–35 years that were important to our understanding of the synthetic pathway required for initiation of the antennae or branches on complex N-glycans and O-glycans. The review deals primarily with the author's contributions but the relevant work of other laboratories is also discussed. The focus of the review is almost entirely on the glycosyltransferases involved in the process. The following topics are discussed. (1) The localization of the synthesis of complex N-glycan antennae to the Golgi apparatus. (2) The evolutionary boundary at the stage in N-glycan processing where there is a change from oligomannose to complex N-glycans; this switch correlates with the appearance of multicellular organisms. (3) The discovery of the three enzymes which play a key role in this switch, N-acetylglucosaminyltransferases I and II and mannosidase II. (4) The yellow brick road which leads from oligomannose to highly branched complex N-glycans with emphasis on the enzymes involved in the process and the factors which control the routes of synthesis. (5) A short discussion of the characteristics of the enzymes involved and of the genes that encode them. (6) The role of complex N-glycans in mammalian and Caenorhabditis elegans development. (7) The crystal structure of N-acetylglucosaminyltransferase I. (8) The discovery of the enzymes which synthesize O-glycan cores 1, 2, 3 and 4 and their elongation.     

Hepatocyte growth factor stimulates the growth and activates mitogen-activated protein kinase in human hepatoma cells

Hepatocyte growth factor (HGF) is a potent mitogen for hepatocytes and various epithelial cells. Unexpectedly, it has been reported to inhibit the growth of hepatoma cells in vitro. To clarify this phenomenon, we examined the effects of recombinant baculovirus-expressed HGF on the growth of 6 human hepatoma cell lines. The growth of Hep3B and HepG2 cells was markedly stimulated to 1.8- and 1.7-fold, respectively, PLC/PRF/5 to 1.4-fold, and SK-Hep-1 to 1.2-fold in a dose-dependent manner under HGF concentrations below 20 ng/ml. Neither HuH-7 nor HCC36 were affected. None of these cells were inhibited. All these cells expressed c-Met, the membrane receptor for HGF, and their c-Met would be activated to be phosphorylated upon addition of HGF. They also contained the ERK2 subgroup of mitogen-activated protein kinases (MAPKs). When HGF was added, their ERK2 would also be phosphorylated. The extent of ERK2 phosphorylation was partially correlated to their growth response to HGF. In conclusion, HGF could stimulate the growth of certain human hepatoma cells, probably through activation of c-Met and MAPKs.     

Experimental vaccine strategies for cancer immunotherapy

Recently, cancer immunotherapy has emerged as a therapeutic option for the management of cancer patients. This is based on the fact that our immune system, once activated, is capable of developing specific immunity against neoplastic but not normal cells. Increasing evidence suggests that cell-mediated immunity, particularly T-cell-mediated immunity, is important for the control of tumor cells. Several experimental vaccine strategies have been developed to enhance cell-mediated immunity against tumors. Some of these tumor vaccines have generated promising results in murine tumor systems. In addition, several phase I/II clinical trials using these vaccine strategies have shown extremely encouraging results in patients. In this review, we will discuss many of these promising cancer vaccine strategies. We will pay particular attention to the strategies employing dendritic cells, the central player for tumor vaccine development.     

Characterization of HTT Inclusion Size,Location, and Timing in the zQ175 Mouse Model of Huntington′s Disease: An In Vivo High-Content Imaging Study

Huntington’s disease (HD) is an autosomal dominant neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the huntingtin gene. Major pathological hallmarks of HD include inclusions of mutant huntingtin (mHTT) protein, loss of neurons predominantly in the caudate nucleus, and atrophy of multiple brain regions. However, the early sequence of histological events that manifest in region- and cell-specific manner has not been well characterized. Here we use a high-content histological approach to precisely monitor changes in HTT expression and characterize deposition dynamics of mHTT protein inclusion bodies in the recently characterized zQ175 knock-in mouse line. We carried out an automated multi-parameter quantitative analysis of individual cortical and striatal cells in tissue slices from mice aged 2–12 months and confirmed biochemical reports of an age-associated increase in mHTT inclusions in this model. We also found distinct regional and subregional dynamics for inclusion number, size and distribution with subcellular resolution. We used viral-mediated suppression of total HTT in the striatum of zQ175 mice as an example of a therapeutically-relevant but heterogeneously transducing strategy to demonstrate successful application of this platform to quantitatively assess target engagement and outcome on a cellular basis.     

A brief review

This article serves as a brief history and review of EBM—how EBM developed, its strengths and limitations, and the need for constant improvements. Hopefully, this review will have enhanced your understanding of EBM and its importance and stimulated you to apply EBM to your own practice. As more data and therapies become available, and as clinical guidelines continue to evolve based on EBM, we should expect patient outcomes to improve.