GST null genotype and antioxidants: Risk indicators for oral pre-cancer and cancer

<b>Objectives</b> : This study was undertaken to detect the gene polymorphism of detoxification enzymes and estimate the antioxidant enzyme status in patients with oral cancer, oral leukoplakia and oral submucous fibrosis (OSF). <b> Materials</b> <b> and</b> <b> Methods</b> : The <i>GSTM1</i> and <i>GSTT1</i> gene polymorphism was evaluated using polymerase chain reaction; the antioxidant enzyme was estimated using biochemical methods. Statistical analyses were performed using student <i>t</i>-test and odds-ratio to estimate relative risk (RR). <b> Results</b> : The RR at 95&#x0025; confidence interval (CI) for <i>GSTM1</i> and <i>GSTT1</i> was statistically significant for all groups. The mean values of glutathione were significantly raised in all groups. The mean values of ceruloplasmin and malonaldehyde was statistically significant among cancer and OSF patients but was insignificant in smokers and cases with leukoplakia. <b>Conclusion</b> : Several genes perform the same function which implies the need to test for several genetic polymorphisms to identify individuals at high risk. The level of antioxidant enzymes correlate with the degree of oxidative damage. The need for further studies is emphasised

Recent advances in diagnostic oral medicine

Oral medicine is an area of dentistry which is constantly changing. Over the past several years Oral medicine has expanded in both scope and complexity. Oral medicine involves the diagnosis and management of complex diagnostic and medical disorders affecting the mouth and jaws. Current decade has witnessed enormous advances in the diagnostic oral medicine, which have moved from the laboratory to the dental clinics and hospitals. It is important that these advances do not remain as domain of the specialists in this field. Every general dental practitioner should be aware of recent advances in diagnostic oral medicine in order to provide a high level of care. This paper discusses the recent technological advances in the field of oral medicine that have made an impact on clinical dental practice

Argyrophilic nuclear organizer region and p73 expression in head and neck squamous cell carcinomas: teammates or adversaries?

Head and neck squamous cell carcinoma (HNSCC) consists of squamous cell carcinomas (SCCs) arising in the upper aerodigestive tract and accounts for 5% of cancers worldwide. In Malaysia, cancers of the nasopharynx, larynx, tongue and oral cavity are among the top twenty most common cancers in men. Argyrophilic nuclear organizer regions (AgNORs) are increased from normal mucosa to premalignant lesions to malignant lesions and have been associated with tumor grade and prognosis of patients. Although p73 is not mutated in human cancers, high levels of p73 expression have been associated with tumor differentiation status and patient prognosis.To investigate the correlation between AgNORs and p73 immunoexpression.Fifty-two formalin-fixed, paraffin-embedded HNSCC cases and ten controls were collected from the Hospital.Tissue blocks were sectioned, dewaxed and rehydrated before silver nitrate staining to determine the AgNOR count and immunohistochemical staining to determine the p73 expression. Adopting the scoring system used by Chen . for p73 staining, the proportion of positively stained cells in the whole epithelial layer was determined. Staining was considered positive if >10% of epithelial cells were stained.Spearman's correlation coefficient was calculated using SPSS 18 software to determine the relationship between the p73 score against tumor differentiation, mean AgNOR counts and tumor grade and between the mean AgNOR count and p73 score.Positive results were found in the immunoexpression of p73. Positive results were seen with the staining of AgNOR; however, in comparison with the entire sample size, a significant correlation between mean AgNOR count and p73 immunohistochemical expression was not obtained.AgNOR count showed a linear and decreasing trend as the p73 score increases. This correlation was statistically insignificant

Anticancer activity of Ophiobolin A, isolated from the endophytic fungus <i>Bipolaris setariae</i>

<p>The present work describes the anticancer activity of Ophiobolin A isolated from the endophytic fungus <i>Bipolaris setariae.</i> Ophiobolin A was isolated using preparative HPLC and its structure was confirmed by HRMS, ¹H NMR, ¹³C NMR, COSY, DEPT, HSQC and HMBC. It inhibited solid and haematological cancer cell proliferation with IC₅₀ of 0.4–4.3 μM. In comparison, IC₅₀ against normal cells was 20.9 μM. It was found to inhibit the phosphorylation of S6 (IC₅₀ = 1.9 ± 0.2 μM), ERK (IC₅₀ = 0.28 ± 0.02 μM) and RB (IC₅₀ = 1.42 ± 0.1 μM), the effector proteins of PI3K/mTOR, Ras/Raf/ERK and CDK/RB pathways, respectively. It induced apoptosis and inhibited cell cycle progression in MDA-MB-231 cancer cells with concomitant inhibition of signalling proteins. Thus, this study reveals that anticancer activity of Ophiobolin A is associated with simultaneous inhibition of multiple oncogenic signalling pathways namely PI3K/mTOR, Ras/Raf/ERK and CDK/RB.</p