Investigation of the in vitro therapeutic efficacy of nilotinib in immortalized human NF2-null vestibular schwannoma cells

Vestibular schwannomas (VS) are a common posterior fossa brain tumor, and though benign can cause significant morbidity, particularly loss of hearing, tinnitus, vertigo and facial paralysis. The current treatment options for VS include microsurgical resection, stereotactic radiosurgery or close surveillance monitoring, with each treatment option carrying associated complications and morbidities. Most importantly, none of these options can definitively reverse hearing loss or tinnitus. Identification of a novel medical therapy, through the use of targeted molecular inhibition, is therefore a highly desirable treatment strategy that may minimize complications arising from both tumor and treatment and more importantly be suitable for patients whose options are limited with respect to surgical or radiosurgical interventions. In this study we chose to examine the effect of Nilotinib on VS. Nilotinib (Tasigna?) is a second-generation receptor tyrosine kinase (RTK) inhibitor with a target profile similar to that of imatinib (Gleevec?), but increased potency, decreased toxicity and greater cellular and tissue penetration. Nilotinib targets not only the BCR-ABL oncoprotein, but also platelet-derived growth factor (PDGF) receptor signalling. In this preclinical study, the human NF2-null schwannoma cell line HEI-193 subjected to nilotinib inhibition demonstrated decreased viability, proliferation and anchorage-independent growth, and increased apoptosis. A daily dose of nilotinib for 5 days inhibited HEI-I93 proliferation at a clinically-relevant concentration in a dose-dependent manner (IC(50) 3-5 μmol/L) in PDGF-stimulated cells. These anti-tumorigenic effects of nilotinib were correlated to inhibited activation of PDGFR-α and PDGFR-β and major downstream signalling pathways. These experiments support a therapeutic potential for Nilotinib in VS.     

Protective efficacy of probiotic alone or in conjunction with a prebiotic in Salmonella-induced liver damage

In view of the increasing interest in the bioecological and nutritional control of diseases, use of probiotics alone or in combination with prebiotics (synbiotics) appears as a therapeutic option for various diseases. In this study, an attempt was made to explore the protective potential of Lactobacillus acidophilus as a probiotic, inulin as a prebiotic and both L. acidophilus and inulin as synbiotic against Salmonella -induced liver damage in a murine model. The probiotic, prebiotic and synbiotic supplementation resulted in decreased bacterial translocation in the liver of mice challenged with Salmonella typhimurium and decreased levels of serum aminotransferases, suggesting their protective role against Salmonella infection. Mice supplemented with these preparations before Salmonella challenge also revealed decreased levels of lipid peroxidation, increased levels of superoxide dismutase and glutathione, along with reduced levels of nitric oxide. Thus, bacteriological and biochemical alterations correlated well with the histological evidence. Protection afforded by supplementation with the probiotic alone was found to be more effective. None of the observations was suggestive of the synergistic effect in the synbiotic-supplemented animals. Thus, it is indicated that the probiotic and the prebiotic used in the present study may act by different mechanisms involved in affording protection against Salmonella -induced liver damage.     

Polymorphisms of IL-6 174 G/C, IL-10 -592 C/A and risk of HIV/AIDS among North Indian population

A growing body of evidence suggests that host genetic factors play an important role both in susceptibility to HIV infection and progression to AIDS. The present study aimed at evaluating the role of IL-6 and IL-10 gene polymorphisms on the risk of HIV susceptibility and disease progression among North Indian patients. The polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) techniques were applied to genotype IL-6 and IL-10. 300 seropositive and an equal number of age- and sex-matched seronegative control subjects were recruited for this study. There was statistically no significant variation in the frequencies of IL-6 and IL-10 genotypes among cases and controls. However, statistically non-significant association for risk of rapid disease progression was observed due to the combined effect of the IL-6 homozygous CC genotype and CC of IL-10, OR = 1.62, 95% CI = 0.38–6.91. Therefore, combined effects of the CC of IL-6 and CC of IL-10 might reduce the hosts ability to hinder viral replication after infection.     

Significance of detection of immune-complexed 8 kDa hydatid-specific antigen for immunodiagnosis of hydatidosis

Abstract Three micro-enzyme-linked immunosorbent assay (micro-ELISA) systems were developed and evaluated for detection of specific free circulating antigen and circulating immune-complexes (CICs) of 8 kDa antigen in the sera of patients with hydatidosis. All (100%) the sera of 30 confirmed positive cases of hydatidosis had detectable levels of antigen in the acid-treated sera. However, 23 (77%) and 26 (87%) sera of 30 confirmed cases had free as well as CICs of 8 kDa antigen in the untreated and in the polyethylene glycol (PEG) precipitated sera, respectively. None of the sera from other patients with parasitic infections or viral hepatitis had any detectable levels of 8 kDa antigen in the untreated, acid-treated or PEG-precipitated serum samples. The investigations, therefore, suggested that the demonstration of circulating antigen employing monospecific antibodies to affinity purified 8 kDa antigen in acid-treated sera is more efficient as compared to detection of free circulating antigen of CICs in the untreated or in the PEG-precipitated sera which could provide a specific immunodiagnostic tool for ongoing hydatid infection.     

Polymorphisms in XPC and XPD genes modulate DNA damage in pesticide-exposed agricultural workers of Punjab,North-West India

Molecular Biology Reports - The genetic susceptibility of individuals to the genotoxic effect of pesticides may be modulated by variations in genes involved in nucleotide excision repair (NER)...     

Effect of capsid confinement on the chromatin organization of the SV40 minichromosome

Using small-angle X-ray scattering, we determined the three-dimensional packing architecture of the minichromosome confined within the SV40 virus. In solution, the minichromosome, composed of closed circular dsDNA complexed in nucleosomes, was shown to be structurally similar to cellular chromatin. In contrast, we find a unique organization of the nanometrically encapsidated chromatin, whereby minichromosomal density is somewhat higher at the center of the capsid and decreases towards the walls. This organization is in excellent agreement with a coarse-grained computer model, accounting for tethered nucleosomal interactions under viral capsid confinement. With analogy to confined liquid crystals, but contrary to the solenoid structure of cellular chromatin, our simulations indicate that the nucleosomes within the capsid lack orientational order. Nucleosomes in the layer adjacent to the capsid wall, however, align with the boundary, thereby inducing a ‘molten droplet’ state of the chromatin. These findings indicate that nucleosomal interactions suffice to predict the genome organization in polyomavirus capsids and underscore the adaptable nature of the eukaryotic chromatin architecture to nanoscale confinement.