Cross-Comparison of Inflammatory Skin Disease Transcriptomics Identifies PTEN as a Pathogenic Disease Classifier in Cutaneous Lupus Erythematosus.

Tissue transcriptomics is used to uncover molecular dysregulations underlying diseases. However, the majority of transcriptomics studies focus on single diseases with limited relevance for understanding the molecular relationship between diseases or for identifying disease-specific markers. In this study, we used a normalization approach to compare gene expression across nine inflammatory skin diseases. The normalized datasets were found to retain differential expression signals that allowed unsupervised disease clustering and identification of disease-specific gene signatures. Using the NS-Forest algorithm, we identified a minimal set of biomarkers and validated their use as diagnostic disease classifier. Among them, PTEN was identified as being a specific marker for cutaneous lupus erythematosus and found to be strongly expressed by lesional keratinocytes in association with pathogenic type I IFNs. In fact, PTEN facilitated the expression of IFN-ß and IFN-κ in keratinocytes by promoting activation and nuclear translocation of IRF3. Thus, cross-comparison of tissue transcriptomics is a valid strategy to establish a molecular disease classification and to identify pathogenic disease biomarkers.

Medical-legal partnerships: the role of mental health providers and legal authorities in the development of a coordinated approach to supporting mental health clients' legal needs in regional and rural settings.

INTRODUCTION: Medical-legal partnerships (MLP) are a model in which medical and legal practitioners are co-located and work together to support the health and wellbeing of individuals by identifying and resolving legal issues that impact patients' health and wellbeing. The aim of this article is to analyse the benefits of this model, which has proliferated in the USA, and its applicability in the context of rural and remote Australia. METHODS: This review was undertaken with three research questions in mind: What is an MLP? Is service provision for individuals with mental health concerns being adequately addressed by current service models particularly in the rural context? Are MLPs a service delivery channel that would benefit individuals experiencing mental health issues? RESULTS: The combined searches from all EBSCO Host databases resulted in 462 citations. This search aggregated academic journals, newspapers, book reviews, magazines and trade publications. After several reviews 38 papers were selected for the final review based on their relevance to this review question: How do MLPs support mental health providers and legal service providers in the development of a coordinated approach to supporting mental health clients' legal needs in regional and rural Australia? CONCLUSIONS: There is considerable merit in pursuing the development of MLPs in rural and remote Australia particularly as individuals living in rural and remote areas have far fewer opportunities to access support services than those people living in regional and metropolitan locations. MLPS are important channels of service delivery to assist in early invention of legal problems that can exacerbate mental health problems.

Oxidative deboronation of the peptide boronic acid proteasome inhibitor bortezomib: contributions from reactive oxygen species in this novel cytochrome P450 reaction.

Bortezomib (1) is a potent first-in-class dipeptidyl boronic acid proteasome inhibitor employed in the treatment of patients with relapsed multiple myeloma where the disease is refractory to conventional lines of therapy. The potency of 1 is owed primarily to the presence of the boronic acid moiety, one which is suited to establish a tetrahedral intermediate with the active site N-terminal threonine residue of the proteasome. Hence, deboronation of 1 represents a deactivation pathway for this chemotherapeutic agent. Deboronation of 1 affords a near equal mixture of diastereomeric carbinolamide metabolites (M1/M2) and represents the principal metabolic pathway observed in humans. In vitro results from human liver microsomes and human cDNA-expressed cytochrome P450 enzymes (P450) indicate a role for P450 in the deboronation of 1. Use of 18O-labeled oxygen under controlled atmospheres confirmed an oxidative mechanism in the P450-mediated deboronation of 1, as 18O was found incorporated in both M1 and M2. Chemically generated reactive oxygen species (ROS), such as those generated as byproducts during P450 catalysis, were also found to deboronate 1 resulting in the formation of M1 and M2. Known to undergo efficient redox cycling, P450 2E1 was found to catalyze the deboronation of 1 predominantly to the carbinolamide metabolites M1 and M2, as well as to a pair of peroxycarbinolamides, 2 and 3. The presence of superoxide dismutase (SOD) and catalase prevented the deboronation of 1, thus, supporting the involvement of ROS in the P450 2E1-catalyzed deboronation reaction. The presence of SOD and catalase also protected 1 against P450 3A4-catalyzed deboronation, albeit to a lesser extent. The remaining deboronation activity observed in the P450 3A4 reaction may suggest the involvement of the more conventional activated enzyme-oxidants previously described for P450. Our present findings indicate that the oxidase activity of P450 (i.e., formation of ROS) represents a mechanism of deboronation.

Mapping the binding site of melanocortin 4 receptor agonists: a hydrophobic pocket formed by I3.28(125), I3.32(129), and I7.42(291) is critical for receptor activation.

The melanocortin 4 receptor is involved in the control of the feeding behavior and energy homeostasis. It is regulated by internal agonist (alpha-MSH) and antagonists (Agouti). Peptide agonists bind in a beta-turn conformation that organizes the characteristic message sequence (His-L/DPhe-Arg-Trp) in an optimal arrangement for binding and activation of the receptor. Our goal is to determine the most likely binding modes of peptide and small molecule agonists to use this information to guide our structure-based drug design efforts. Previous studies have identified some residues that are likely to be involved in peptide agonist binding, giving an initial estimate of the main contacts between peptides and receptor. However, a more detailed description of the orientation of the peptide in a beta-turn conformation in the binding site, as well as of the small molecule agonists, and it is commonalities with the peptide agonist binding modes is necessary to serve as the basis for structure-based drug design. In the current study we combine site-directed mutagenesis with molecular modeling studies to determine the most likely binding mode of peptide and small molecule agonists, and we found that Y6.58(268), Y7.38(287), I3.28(125), I3.32(129), and I7.42(291) also line the binding site and are likely to have direct contacts with the MC4R agonists. Of particular interest are residues I3.28(125), I3.32(129), and I7.42(291), which form a hydrophobic pocket where I7.42(291), on top of the NPXXY motif, is likely to act as a new rotamer switch implicated in the activation of the receptor.

Human metabolism of the proteasome inhibitor bortezomib: identification of circulating metabolites.

Bortezomib [N-(2,3-pyrazine)carbonyl-L-phenylalanine-L-leucine boronic acid] is a potent first-in-class dipeptidyl boronic acid proteasome inhibitor that was approved in May 2003 in the United States for the treatment of patients with relapsed multiple myeloma where the disease is refractory to conventional lines of therapy. Bortezomib binds the proteasome via the boronic acid moiety, and therefore, the presence of this moiety is necessary to achieve proteasome inhibition. Metabolites in plasma obtained from patients receiving a single intravenous dose of bortezomib were identified and characterized by liquid chromatography/mass spectrometry (LC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Metabolite standards that were synthesized and characterized by LC/MS/MS and high field nuclear magnetic resonance spectroscopy (NMR) were used to confirm metabolite structures. The principal biotransformation pathway observed was oxidative deboronation, most notably to a pair of diastereomeric carbinolamide metabolites. Further metabolism of the leucine and phenylalanine moieties produced tertiary hydroxylated metabolites and a metabolite hydroxylated at the benzylic position, respectively. Conversion of the carbinolamides to the corresponding amide and carboxylic acid was also observed. Human liver microsomes adequately modeled the in vivo metabolism of bortezomib, as the principal circulating metabolites were observed in vitro. Using cDNA-expressed cytochrome P450 isoenzymes, it was determined that several isoforms contributed to the metabolism of bortezomib, including CYP3A4, CYP2C19, CYP1A2, CYP2D6, and CYP2C9. The development of bortezomib has provided an opportunity to describe the metabolism of a novel boronic acid pharmacophore.

A Molecular Chameleon: Chromophoric Sensing by a Self-Complexing Molecular Assembly.

A color change from purple to green takes place on addition of tetrathiafulvalene (TTF) to the macrobicyclic receptor 14+ , which is composed of a cyclobis(paraquat-p-phenylene) tetracation that shares one of its paraphenylene rings with a 1,5-naphthoparaphenylene-[36]crown-10 macrocycle. The TTF molecule forces the macrobicycle to turn inside out (see schematic drawing below) and displaces the self-complexed 1,5-dioxynaphthalene ring system from the center of the tetracationic cyclophane.