Clinicopathological significance of PTEN and bcl2 expressions in oral squamous cell carcinoma

A high frequency of mutations at the PTEN locus has been noticed in carcinoma of oral. However, the role of PTEN alternations and its association with outcome variables in the genesis of oral carcinoma is not understood fully. The purpose of our study was to examine the impact of PTEN and Bcl2 in the genesis of Squamous cell carcinoma of oral. Total numbers of 60 histopathologically confirmed cases of Squamous Cell Carcinoma and 15 cases of inflammatory lesion of oral specimens were studied. We assessed PTEN and bcl2 overexpression by the use of anti-PTEN and anti-bcl2 antibody through immunohistochemistry as directed by the manufacturer. There was progressive loss of PTEN expression from inflammatory lesion to OSCC (p<0.05). Significant differences were found for PTEN expression between inflammatory lesion and OSCC. The difference in expression pattern of PTEN in gender did not reach statistical significance (p>0.05). The expression of bcl2 was found to be restricted to tumor cells in well and moderately differentiated tumors. The intense expression of bcl2 was observed throughout the tumor cell in poorly differentiated tumors.The Overexpression of bcl2 and loss of PTEN expression were correlated to poor differentiation, lymph node involvement and late stages. Thus, alteration of PTEN and bcl2 is likely an important molecular event in pathogenesis and carcinogenesis of oral carcinoma.     

Molecular interactions of dioxins and DLCs with the ketosteroid receptors: an in silico risk assessment approach

Dioxins and dioxin-like compounds (DLCs) are the ones with poor water solubility and low volatility, resistant to physical, chemical and biological processes, persistent in the environment even under extreme conditions. Due to lipophilic nature, they get adhered to the fatty material and concentrate through biomagnification and bioaccumulation, thereby easily getting incorporated into food chains, paving the way to endocrine disruption via modulation of various human receptors. This in turn leads to certain adverse health effects. In the present study, a total of 100 dioxins and DLCs were taken and their binding pattern was assessed with the ketosteroid receptors, i.e. androgen (hAR), glucocorticoid (hGR), progesterone (hPR) and mineralocorticoid (hMR) in comparison to the corresponding natural steroids and a known endocrine disrupting xenobiotic, Bisphenol A (BPA). Most of the DLCs, particularly those bearing hydroxyl (-OH) group showed considerable affinities with ketosteroid receptors. On comparing D scores of all the dioxins and DLCs against all four receptors, compound 8-hydroxy-3,4-dichlorodibenzofuran(8-OH-DCDF) exhibited least D score of -9.549?kcal mol^?1 against hAR. 3,8-Dihydroxy-2-chlorodibenzofuran(3,8-DiOH-CDF), 4′-hydroxy-2,3,4,5-tetrachlorobiphenyl (4′-OH-TCB) and 4-hydroxy-2,2′,5′-trichlorobiphenyl(4-OH-TCB) also showed comparable molecular interactions with the ketosteroid receptors. These interactions mainly include H-bonding, π–π stacking, hydrophobic, polar and van der Waals’ interactions. In contrast, BPA and some natural ligands tested in this study showed lower binding affinities with these receptors than certain DLCs reported herein, i.e. certain DLCs might be more toxic than the proven toxic agent, BPA. Such studies play a pivotal role in the risk assessment of exposure to dioxins and DLCs on human health.     

Altered sensitivity to nitric oxide donors,induced by intravascular infusion of quantum dots,in murine mesenteric arteries

Quantum dots (QDs) are utilised in imaging diagnostics, tissue engineering and medical therapeutics, however, their influence on vascular function is not ascertained. Here, we examined small mesenteric arterial responses after acute intravascular exposure to QDs. Incubation in mercaptoundecanoic acid (MUA)-coated QDs (at 15 μg/mL) had no influence on endothelial-dependent dilator responses (Acetylcholine; Ach) but led to an attenuated relaxation to the nitric oxide donor, sodium nitroprusside (SNP). Conversely, incubation in POSS-PCU coated QDs (at 15 μg/mL) led to attenuated Ach responses (10^? 11–10^? 3 M; n = 5, P < 0.05), but had no influence on SNP-induced relaxation. At lower concentrations of POSS-PCU coated QDs (5 μg/mL), Ach responses were preserved. We demonstrate that acute exposure to QDs, can attenuate vasodilation but not vasoconstriction, and is dependent on their surface coatings. Our findings have implications in QD use for imaging diagnostics in disease states, where SNP based drugs are used in therapeutic intervention.From the Clinical EditorIn this paper, the influence of quantum dots on vascular function is investigated---an important aspect to consider with the growing utility of quantum dots in imaging diagnostics, tissue engineering and medical therapeutics.     

Malignant melanoma representing with testicular metastasis: a case report and review of the literature

We present the case of a 52-year-old man, with a history of malignant melanoma, who presented with a testicular lump. Radical orchidectomy confirmed a metastatic malignant melanoma. We discuss salient features of this disease in the light of the published literature.