The molecular basis of copper-transport diseases

Copper (Cu) is a potentially toxic yet essential element. Menkes disease, a copper deficiency disorder, and Wilson disease, a copper toxicosis condition, are two human genetic disorders, caused by mutations of two closely related Cu-transporting ATPases. Both molecules efflux copper from cells. Quite diverse clinical phenotypes are produced by different mutations of these two Cu-transporting proteins. The understanding of copper homeostasis has become increasingly important in clinical medicine as the metal could be involved in the pathogenesis of some important neurological disorders such as Alzheimer's disease, motor neurone diseases and prion diseases.

Clincial pharmacogenetics and potential application in personalized medicine

The current `fixed-dosage strategy' approach to medicine, means there is much inter-individual variation in drug response. Pharmacogenetics is the study of how inter-individual variations in the DNA sequence of specific genes affect drug responses. This article will highlight current  pharmacogenetic knowledge on important drug metabolizing enzymes, drug transporters and drug targets to understand interindividual variability in drug clearance and responses in clinical practice and potential use in  personalized medicine. Polymorphisms in the cytochrome P450 (CYP) family may have had the most impact on the fate of pharmaceutical drugs. CYP2D6, CYP2C19 and CYP2C9 gene polymorphisms and gene duplications account for the most frequent variations in phase I metabolism of drugs since nearly 80% of drugs in use today are metabolised by these enzymes. Approximately 5% of Europeans and 1% of Asians lack CYP2D6 activity, and these  individuals are known as poor metabolizers. CYP2C9 is another clinically significant drug metabolising enzyme that demonstrates genetic variants. Studies into CYP2C9 polymorphism have highlighted the importance of the CYP2C9*2 and CYP2C9*3 alleles. Extensive polymorphism also occurs in a majority of Phase II drug metabolizing enzymes. One of the most important polymorphisms is thiopurine S-methyl transferases (TPMT) that catalyzes the S-methylation of thiopurine drugs. With respect to drug transport  polymorphism, the most extensively studied drug transporter is  P-glycoprotein (P-gp/MDR1), but the current data on the clinical impact is limited. Polymorphisms in drug transporters may change drug's distribution, excretion and response. Recent advances in molecular research have revealed many of the genes that encode drug targets demonstrate genetic polymorphism. These variations, in many cases, have altered the targets sensitivity to the specific drug molecule and thus have a profound effect on drug efficacy and toxicity. For example, the β2-adrenoreceptor, which is encoded by the ADRB2 gene, illustrates a clinically significant genetic variation in drug targets. The variable number tandem repeat polymorphisms in serotonin transporter (SERT/SLC6A4) gene are associated with response to antidepressants. The distribution of the common variant alleles of genes that encode drug metabolizing enzymes, drug transporters and drug targets has been found to vary among different populations. The promise of pharmacogenetics lies in its potential to identify the right drug at the right dose for the right individual. Drugs with a narrow therapeutic index are thought to benefit more from pharmacogenetic studies. For example, warfarin serves as a good practical example of how pharmacogenetics can be utilized prior to commencement of therapy in order to achieve maximum efficacy and minimum toxicity. As such, pharmacogenetics has the potential to achieve optimal quality use of medicines, and to improve the efficacy and safety of both prospective and licensed drugs.

Regulation of human pregnane X receptor and its target gene cytochrome P450 3A4 by Chinese herbal compounds and a molecular docking study

1. The pregnane X receptor (PXR) plays a critical role in the regulation of human cytochrome P450 3A4 (CYP3A4) gene. In this study, we investigated the effect of an array of compounds isolated from Chinese herbal medicines on the activity of PXR using a luciferase reporter gene assay in transiently transfected HepG2 and Huh7 cells and on the expression of PXR and CYP3A4 in LS174T cells. Furthermore, molecular docking was performed to investigate the binding modes of herbal compounds with PXR.

2. Praeruptorin A and C, salvianolic acid B, sodium danshensu, protocatechuic aldehyde, cryptotanshinone, emodin, morin, and tanshinone IIA significantly transactivated the CYP3A4 reporter gene construct in either HepG2 or Huh7 cells. The PXR mRNA expression in LS174T cells was significantly induced by physcion, protocatechuic aldehyde, salvianolic acid B, and sodium danshensu. However, epifriedelanol, morin, praeruptorin D, mulberroside A, tanshinone I, and tanshinone IIA significantly down-regulated the expression of PXR mRNA in LS174T cells.

3. All the herbal compounds tested can be readily docked into the ligand-binding cavity of PXR mainly through hydrogen bond and aromatic interactions with Ser247, Gln285, His407, and Arg401.

4. These findings suggest that herbal medicines can significantly regulate PXR and CYP3A4 and this has important implication in herb–drug interactions.

Emerging engineered magnetic nanoparticulate probes for molecular MRI of atherosclerosis : how far have we come?

Atherosclerosis is a chronic, progressive, immunoinflammatory disease of the large and medium-sized arteries, and a major cause of cardiovascular diseases. Atherosclerosis often progresses silently for decades until the occurrence of a major catastrophic clinical event such as myocardial infarction, cardiac arrest and stroke. The main challenge in the diagnosis and management of atherosclerosis is to develop a safe, noninvasive technique that is accurate and reproducible, which can detect the biologically active high-risk vulnerable plaques (with ongoing active inflammation, angiogenesis and apoptosis) before the occurrence of an acute clinical event. This Journal Article reviews the events involved in the pathogenesis of atherosclerosis in light of recently advanced understanding of the molecular pathogenesis of the disease. Next, we elaborate on the interesting developments in molecular MRI, by describing the recently engineered magnetic nanoparticulate probes targeting clinically promising molecular and cellular players/processes, involved in early atherosclerotic lesion formation to plaque rupture and erosion.

Identification of unprecedented anticancer properties of high molecular weight biomacromolecular complex containing bovine lactoferrin (HMW-bLf)

With the successful clinical trials, multifunctional glycoprotein bovine lactoferrin is gaining attention as a safe nutraceutical and biologic drug targeting cancer, chronic-inflammatory, viral and microbial diseases. Interestingly, recent findings that human lactoferrin oligomerizes under simulated physiological conditions signify the possible role of oligomerization in the multifunctional activities of lactoferrin molecule during infections and in disease targeting signaling pathways. Here we report the purification and physicochemical characterization of high molecular weight biomacromolecular complex containing bovine lactoferrin (≥250 kDa), from bovine colostrum, a naturally enriched source of lactoferrin. It showed structural similarities to native monomeric iron free (Apo) lactoferrin (∼78-80 kDa), retained anti-bovine lactoferrin antibody specific binding and displayed potential receptor binding properties when tested for cellular internalization. It further displayed higher thermal stability and better resistance to gut enzyme digestion than native bLf monomer. High molecular weight bovine lactoferrin was functionally bioactive and inhibited significantly the cell proliferation (p<0.01) of human breast and colon carcinoma derived cells. It induced significantly higher cancer cell death (apoptosis) and cytotoxicity in a dose-dependent manner in cancer cells than the normal intestinal cells. Upon cellular internalization, it led to the up-regulation of caspase-3 expression and degradation of actin. In order to identify the cutting edge future potential of this bio-macromolecule in medicine over the monomer, its in-depth structural and functional properties need to be investigated further.

Ionic liquids for energy, materials, and medicine.

As highlighted by the recent ChemComm web themed issue on ionic liquids, this field continues to develop beyond the concept of interesting new solvents for application in the greening of the chemical industry. Here some current research trends in the field will be discussed which show that ionic liquids research is still aimed squarely at solving major societal issues by taking advantage of new fundamental understanding of the nature of these salts in their low temperature liquid state. This article discusses current research trends in applications of ionic liquids to energy, materials, and medicines to provide some insight into the directions, motivations, challenges, and successes being achieved with ionic liquids today.

Molecular insights and oligonucleotide based targeted gene therapy against cancer

The thesis helps to unravel the function of T lymphoma invasion and metastasis protein (TIAM1) and nucleolin, a nucleolar protein in retinoblastoma tumorigenesis. Aptamer based targeted imaging; drug and gene delivery to retinoblastoma and epithelial cancer cells was attained. The work work finally opened up avenues for cancer stem cell targeting using aptamers, imaging of cancer cells using novel bio-orthogonal agent and use of aptamer for blocking the miRNA-17-92 cluster maturation.

Molecular regulation of survivin targeted nano-therapy in advanced prostate cancer

 The increasing complexities of prostate cancer disease progression necessitates more stable and less toxic therapeutic strategies. The current study demonstrated for the first time, the survivin targeted anti-cancer therapeutic activity of the bio-molecular drugs such as SurR9-C84A and bovine lactoferrin in inducing prostate cancer specific apoptosis. Moreover, improved therapeutic efficacy was conferred to these bio-molecules either by their encapsulation in stem cell targeted bio-compatible nanoparticles, or by the synthesis of protein-cytotoxic drug conjugates. This study also highlighted the role played by miRNAs in the regulation of iron metabolism and apoptosis, mediated by the selective activation of p53 and PTEN pathways.

"Cancer 2015": a prospective, population-based cancer cohort-phase 1: feasibility of genomics-guided precision medicine in the clinic

"Cancer 2015" is a longitudinal and prospective cohort. It is a phased study whose aim was to pilot recruiting 1000 patients during phase 1 to establish the feasibility of providing a population-based genomics cohort. Newly diagnosed adult patients with solid cancers, with residual tumour material for molecular genomics testing, were recruited into the cohort for the collection of a dataset containing clinical, molecular pathology, health resource use and outcomes data. 1685 patients have been recruited over almost 3 years from five hospitals. Thirty-two percent are aged between 61-70 years old, with a median age of 63 years. Diagnostic tumour samples were obtained for 90% of these patients for multiple parallel sequencing. Patients identified with somatic mutations of potentially "actionable" variants represented almost 10% of those tumours sequenced, while 42% of the cohort had no mutations identified. These genomic data were annotated with information such as cancer site, stage, morphology, treatment and patient outcomes and health resource use and cost. This cohort has delivered its main objective of establishing an upscalable genomics cohort within a clinical setting and in phase 2 aims to develop a protocol for how genomics testing can be used in real-time clinical decision-making, providing evidence on the value of precision medicine to clinical practice.

Cancer 2015: a longitudinal whole-of-system study of genomic cancer medicine

Genomic cancer medicine promises revolutionary change in oncology. The impacts of 'personalized medicine', based upon a molecular classification of cancer and linked to targeted therapies, will extend from individual patient outcomes to the health economy at large. To address the 'whole-of-system' impact of genomic cancer medicine, we have established a prospective cohort of patients with newly diagnosed cancer in the state of Victoria, Australia, about whom we have collected a broad range of clinical, demographic, molecular, and patient-reported data, as well as data on health resource utilization. Our goal is to create a model for investigating public investment in genomic medicine that maximizes the cost:benefit ratio for the Australian community at large.

Cancer cachexia: a molecular nutrition approach to cancer-related muscle loss

The project identified changes in molecular markers of antioxidant status and muscle atrophy during cancer-associated weight-loss, and confirmed omega-3 EPA as an effective treatment for muscle-loss in experimental cancer cachexia. The project also identified the PG-SGA nutrition tool as a powerful predictor of patient outcomes and survival in clinical cachexia.

Molecular architecture of Aβ fibrils grown in cerebrospinal fluid solution and in a cell culture model of Aβ plaque formation

OBJECTIVES: The detailed structure of brain-derived Aβ amyloid fibrils is unknown. To approach this issue, we investigate the molecular architecture of Aβ(1-40) fibrils grown in either human cerebrospinal fluid solution, in chemically simple phosphate buffer in vitro or extracted from a cell culture model of Aβ amyloid plaque formation. METHODS: We have used hydrogen-deuterium exchange (HX) combined with nuclear magnetic resonance, transmission electron microscopy, seeding experiments both in vitro and in cell culture as well as several other spectroscopic measurements to compare the morphology and residue-specific conformation of these different Aβ fibrils. RESULTS AND CONCLUSIONS: Our data reveal that, despite considerable variations in morphology, the spectroscopic properties and the pattern of slowly exchanging backbone amides are closely similar in the fibrils investigated. This finding implies that a fundamentally conserved molecular architecture of Aβ peptide fold is common to Aβ fibrils.

Targeting Survivin and molecular regulation of de-differentiated grade IV Astrocytoma (Glioblastoma)

The study unprecendently provided evidence about the molecular understanding of a dedifferentiation phenotype of glioblastoma-a highly aggressive brain tumour with 12-15 months of patient survival after diagnosis. Further, the efficacies of survivin targeting molecules SurR9-C84A and a natural non-toxic protein bovine lactoferrin as a safe bio-drug to target glioblastoma were evaluated

Chasing the personalized medicine dream through biomarker validation in colorectal cancer.

Colorectal cancer (CRC) is a major health burden worldwide. The optimal approach to the diagnosis, management, and treatment of CRC involves multidisciplinary and integrated management practices. The field is rapidly changing because of recent advancements in delineating the molecular basis of tumorigenesis, introduction of targeted therapy, varied patient response to mainstay chemotherapeutics, biological drugs, and the effective combination regimes being used for treatment. Recent meta-analysis studies, which tend to establish few clinically useful predictor biomarkers, identify inconsistent results and limitations of the trials. Therefore, molecular pathological epidemiology discipline initiatives are promising. Here, we provide an overview of the potential of biomarker validation for personalized medicine by focusing largely on metastatic (m)CRC. We also highlight new candidate predictive and prognostic biomarkers.