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Increased oxidative stress and altered anti-oxidant defense systems have been implicated in the pathogenesis of several diseases including cancer. Therefore, the aim of our study is to evaluate the antioxidant enzyme levels such as superoxide dismutase (SOD) and catalase in blood samples and tissues collected from oral squamous cell carcinoma patients and compared with healthy controls.The collected blood samples and tumor tissues from the diseased individuals and the normal controls are analyzed for malondialdehyde (MDA) and nitric oxide (NO), which is the indicator of oxidative and nitrosative stress respectively. The anti-oxidant enzymes SOD and catalase levels are measured by UV visible spectrophotometer. Subsequently, immuno-histostaining for antioxidant enzymes were performed in oral squamous cell carcinoma biopsies and sections were analyzed.The levels of MDA and NO were significantly elevated in the blood and tissue samples of OSCC patients. The antioxidant enzymes SOD and catalase were significantly reduced in OSCC tissues; while in erythrocytes catalase level is reduced whereas the SOD level is increased. Further, the reduced immuno-histostaining was observed for catalase and SOD in OSCC tissues when compared to normal oral epithelium.The enhanced levels of MDA and NO revealed that increased oxidative stress in conjunction with the reduced antioxidant defense mechanism in OSCC patients, might be involved in cancer progression. Our results suggest that detection of reactive oxygen species (ROS) and antioxidant enzymes levels might be a valuable marker in cancer prognosis and for improving therapeutic strategies in oral cancer.

BackgroundTo investigate the clinical features and the underlying causal gene of a family with hereditary late-onset deafness in Inner Mongolia of China, and to provide evidence for the early genetic screening and diagnosis of this disease.MethodsFamily data were collected to draw a pedigree. Audiological testing and physical examination of the family members were conducted following questionnaire. Genomic DNA was extracted from peripheral blood of 5 family members (3 patients and 2 normal control) and subjected to whole genome sequencing for identifying deafness casual genes. The pathogenic variant in the deafness gene was further confirmed by Sanger sequencing.ResultsThe family is composed of a total of 6 generations, with 53 traceable individuals. In this family,19 of them were diagnosed with post lingual deafness with the age of onset between 10 and 40 years, displaying delayed and progressive hearing loss. Patients with hearing loss showed bilateral symmetry and mild to severe sensorineural deafness. The pattern of deafness inheritance in this family is autosomal dominant. Whole genome sequencing identified a novel pathogenic frameshift mutation, c.158_159delAA (p.Gln53Arg fs*100) in the gene OSBPL2 (Oxysterol-binding protein-related protein 2, NM_144498.2), which is absent from genomic data of 201 unrelated normal subjects. This pathogenic variant was further validated by Sanger sequencing, and was found to co-segregate in this family.ConclusionsWhole genome sequencing identified a two-nucleotide deletion in OSBPL2 (c.158_159delAA) as the pathogenic variant for deafness in the family. Our finding expands the mutational spectrum of OSBPL2 and contributes to the pathogenic variant list in genetic counseling for deafness screening.Electronic supplementary materialThe online version of this article (10.1186/s12881-019-0781-3) contains supplementary material, which is available to authorized users.