Shedding light on the EpCAM: An overview

The epithelial cell adhesion molecule (EpCAM) is a Type I transmembrane superficial glycoprotein antigen that is expressed on the surface of basolateral membrane of multiple epithelial cells with some exceptions such as epidermal keratinocytes, hepatocytes, thymic cortical epithelial cells, squamous stratified epithelial cells, and myoepithelial cells that do not express the molecule. The molecule plays a pivotal role in the structural integrity, adhesion of the epithelial tissues and their interaction with the underlying layers. EpCAM prevents claudin-7 and claudin-1 molecules from degradation, thereby, decreasing the number of tight junctions and cellular interconnections, and promoting the cells toward carcinogenic transformation. Moreover, the mutations in the EpCAM gene lead to congenital tufting enteropathy, severe intestinal epithelium homeostasis disorders, and Lynch and Lynch syndrome. Overexpression of EpCAM on stem cells of some cancers and the presence of this molecule on circulating tumor cells (CTCs) makes it a promising candidate for cancer diagnosis as well as tracing and isolation of CTCs.     

Serological detection of Sharka quarantine disease (Plum pox virus) on stone fruit trees in Golestan province

Sharka disease is one of the most damaging diseases of fruit trees in the world, which is caused by Plum pox virus (PPV) that belongs to the genus Potyvirus in the family Potyviridae. Each year, this virus decreases the yield and causes substantial economic damages to its host plants worldwide. This virus is quarantined in Iran but in recent years, suspicious symptoms of the disease were observed in different grown areas, such as Golestan province. During 2010, 420 samples with mosaic, chlorosis, necrosis, ring pattern, blotches, etc. symptoms were collected from the gardens in Golestan province that included 100 samples from plum, 100 from peach and 240 from nectarine. These samples were evaluated using a double-antibody sandwich-ELISA (DAS-ELISA) method and a polyclonal antibody. The results of this survey indicated that among the total of 420 samples, none of them showed positive reaction in DAS-ELISA test.     

The role of FOXP3 rs3761548 and rs2294021 polymorphisms in pediatrics acute lymphoblastic leukemia: association with risk and response to therapy

FOXP3 X-linked gene has crucial roles in the development and function of regulatory T cells. We investigated the association of FOXP3 rs3761548, rs3761549 and rs2294021 single nucleotide polymorphisms (SNPs) with acute lymphoblastic leukemia (ALL) susceptibility and response to therapy. Genotyping was performed in 247 patients and 210 healthy subjects. We observed a higher frequency of rs3761548 A carriers and rs2294021 C carriers (p?<?0.04) in male patients, and lower frequencies of rs3761548 AC genotype (p?=?0.04) and rs2294021 CT genotype (p?=?0.01) in female patients compared to controls. ACC (p?=?0.04) and ATC haplotypes (p?=?0.002) were associated with susceptibility to ALL. There was a significant correlation between the genotypes of rs3761548 and rs2294021 SNPs with event-free survival (EFS) and overall survival (OS). The rs3761548 A genotype in male patients was associated with increased risk of relapse (p?<?0.0001), shorter EFS, increased death rate (p?=?0.002) and shorter OS compared to C genotype (p?=?0.001). Similar significant results were observed for the relation of rs2294021 C genotype with response to therapy in male patients. In females, patients with rs3761548 AC genotype had longer EFS (p?=?0.02) and those with rs2294021 CT had longer EFS and OS (p?<?0.005). According to haplotype analysis, patients carrying ACC or ATC haplotypes had the highest number of WBCs and shorter EFS or OS, and patients with CCT haplotype had the lowest number of WBCs and longer EFS or OS. These results provided evidence for the impact of these polymorphisms on susceptibility and response to therapy in children with ALL.

     

Reduction of the prenatal hypoxic-ischemic brain edema with noscapine

Cytotoxic free radicals and release of several neurotransmitters such as bradykinin contribute to the pathogenesis of hypoxic-ischemic brain damage. We have studied the efficacy of noscapine, an opium alkaloid and a bradykinin antagonist, in reducing post-hypoxic-ischemic damage in developing brain of 7-d-old rat pups. Hypoxic-ischemic injury to the right cerebral hemisphere was produced by legation of the right common carotid artery followed by 3 h of hypoxia with 8% oxygen. Thirty to 45 min before hypoxia the rat pups received noscapine (dose = 0.5-2 mg/kg) or saline. Pups were scarified at 24 h post recovery for the assessment of cerebral damage by histological methods. Our results showed that noscapine was an effective agent in reducing the extent of brain injury after hypoxic-ischemic insult to neonatal rats. Therefore, it is concluded that noscapine may be a useful drug in the managements of patients after stroke.     

Three proline rotamases involved in calcium homeostasis play differential roles in stress tolerance,virulence and calcineurin regulation of Beauveria bassiana

FK506‐sensitive proline rotamases (FPRs), also known as FK506‐binding proteins (FKBPs), can mediate immunosuppressive drug resistance in budding yeast but their physiological roles in filamentous fungi remain opaque. Here, we report that three FPRs (cytosolic/nuclear 12.15‐kD Fpr1, membrane‐associated 14.78‐kD Fpr2 and nuclear 50.43‐kD Fpr3) are all equally essential for cellular Ca²⁺ homeostasis and contribute significantly to calcineurin activity at different levels in the insect‐pathogenic fungus Beauveria bassiana although the deletion of fpr1 alone conferred resistance to FK506. Radial growth, conidiation, conidial viability and virulence were less compromised in the absence of fpr1 or fpr2 than in the absence of fpr3, which abolished almost all growth on scant media and reduced growth moderately on rich media. The Δfpr3 mutant was more sensitive to Na⁺, K⁺, Mn²⁺, Ca²⁺, Cu²⁺, metal chelate, heat shock and UVB irradiation than was Δfpr2 while both mutants were equally sensitive to Zn²⁺, Mg²⁺, Fe²⁺, H₂O₂ and cell wall‐perturbing agents. In contrast, the Δfpr1 mutant was less sensitive to fewer stress cues. Most of 32 examined genes involved in DNA damage repair, Na⁺/K⁺ detoxification or osmotolerance and Ca²⁺ homeostasis were downregulated sharply in Δfpr2 and Δfpr3 but rarely so affected in Δfpr1, coinciding well with their phenotypic changes. These findings uncover important, but differential, roles of three FPRs in the fungal adaptation to insect host and environment and provide novel insight into their essential roles in calcium signalling pathway.     

Impact of ABCB1 and CYP2B6 Genetic Polymorphisms on Methadone Metabolism,Dose and Treatment Response in Patients with Opioid Addiction: A Systematic Review and Meta-Analysis

Background

Genetic variability may influence methadone metabolism, dose requirements, and risk of relapse.

Objectives

To determine whether the CYP2B6*6 or ABCB1 (rs1045642) polymorphisms are associated with variation in methadone response (plasma concentration, dose, or response to treatment).

Methods

Two independent reviewers searched Medline, EMBASE, CINAHL, PsycINFO, and Web of Science databases. We included studies that reported methadone plasma concentration, methadone response, or methadone dose in relation to the CYP2B6*6 or ABCB1 polymorphisms.

Results

We screened 182 articles and extracted 7 articles for inclusion in the meta-analysis. Considerable agreement was observed between the two independent raters on the title (kappa, 0.82), abstract (kappa, 0.43), and full text screening (kappa, 0.43). Trough (R) methadone plasma concentration was significantly higher in CYP2B6*6 homozygous carriers when compared to non-carriers (standardized mean difference [SMD] = 0.53, 95% confidence interval [CI], 0.05–1.00, p = 0.03) with minimal heterogeneity (I² = 0%). Similarly, trough (S) methadone plasma concentration was higher in homozygous carriers of the *6 haplotype when compared to non-carriers, (SMD = 1.44, 95% CI 0.27–2.61, p = 0.02) however significant heterogeneity was observed (I² = 69%). Carriers of the CYP2B6*6 haplotype were not found to be significantly different from non-carriers with respect to dose or response to treatment. We found no significant association between the ABCB1 polymorphism and the trough (R), (S) plasma concentrations, methadone dose, or methadone response.

Conclusion

Although the number of studies included and sample size were modest, this is the first meta analysis to show participants homozygous for the CYP2B6*6 genotype have higher trough (R) and (S) methadone plasma concentrations, suggesting that methadone metabolism is significantly slower in *6 homozygous carriers.     

Isolation and characterization of the mycobacterial phagosome: segregation from the endosomal/lysosomal pathway

Mycobacteria have the ability to persist within host phagocytes, and their success as intracellular pathogens is thought to be related to the ability to modify their intracellular environment. After entry into phagocytes, mycobacteria-containing phagosomes acquire markers for the endosomal pathway, but do not fuse with lysosomes. The molecular machinery that is involved in the entry and survival of mycobacteria in host cells is poorly characterized. Here we describe the use of organelle electrophoresis to study the uptake of Mycobacterium bovis bacille Calmette Guerin (BCG) into murine macrophages. We demonstrate that live, but not dead, mycobacteria occupy a phagosome that can be physically separated from endosomal/lysosomal compartments. Biochemical analysis of purified mycobacterial phagosomes revealed the absence of endosomal/lysosomal markers LAMP-1 and β-hexosaminidase. Combining subcellular fractionation with two-dimensional gel electrophoresis, we found that a set of host proteins was present in phagosomes that were absent from endosomal/lysosomal compartments. The residence of mycobacteria in compartments outside the endosomal/lysosomal system may explain their persistence inside host cells and their sequestration from immune recognition. Furthermore, the approach described here may contribute to an improved understanding of the molecular mechanisms that determine the intracellular fate of mycobacteria during infection.