A systematic review of proteomic biomarkers in oral squamous cell cancer.

BACKGROUND: Head and neck squamous cell cancer (HNSCC) is the most common cancer associated with chewing tobacco, in the world. As this is divided in to sites and subsites, it does not make it to top 10 cancers. The most common subsite is the oral cancer. At the time of diagnosis, more than 50% of patients with oral squamous cell cancers (OSCC) had advanced disease, indicating the lack of availability of early detection and risk assessment biomarkers. The new protein biomarker development and discovery will aid in early diagnosis and treatment which lead to targeted treatment and ultimately a good prognosis. METHODS: This systematic review was performed as per PRISMA guidelines. All relevant studies assessing characteristics of oral cancer and proteomics were considered for analysis. Only human studies published in English were included, and abstracts, incomplete articles, and cell line or animal studies were excluded. RESULTS: A total of 308 articles were found, of which 112 were found to be relevant after exclusion. The present review focuses on techniques of cancer proteomics and discovery of biomarkers using these techniques. The signature of protein expression may be used to predict drug response and clinical course of disease and could be used to individualize therapy with such knowledge. CONCLUSIONS: Prospective use of these markers in the clinical setting will enable early detection, prediction of response to treatment, improvement in treatment selection, and early detection of tumor recurrence for disease monitoring. However, most of these markers for OSCC are yet to be validated.

Co-circulation of dengue virus serotypes in Central India: Evidence of prolonged viremia in DENV-2.

In view of paucity of information on serotype distribution of Dengue virus (DENV) in Central India, we undertook a cross-sectional study to identify clinical and virological characteristics of DENV serotypes that circulated in this region during the 2016 outbreak. Suspected cases were screened by ELISA for NS1 antigen and anti-DENV IgM antibodies. Serologically confirmed cases were subjected to RT-PCR based detection and serotyping. The RT-PCR results were confirmed by nucleotide sequencing. Genome-wide association was undertaken with DENV sequences from ViPR database and the immune evasion potential of infecting serotypes was ascertained by computing antigenic variability in B cell and Cytotoxic T cell (CTL) epitopes of all DENV proteins. The immunological basis of more prolonged viremia in DENV2-infected patients was also addressed through sequencing of NS2a gene and comparing the CTL activity in NS2a sequences identified among patients with ≤5 days and >5 days of illness. Among 166 serologically confirmed Dengue patients, 75 were positive for DENV RNA. Serotyping revealed predominance of DENV-1 and DENV-2, followed by DENV-3. Co-infection with multiple serotypes was observed in 15.5% of cases. In ~40% cases, DENV RNA was detectable beyond 5 days, among whom majority were DENV-2 infected (p = .044). Highest prevalence of antigenic variability was observed in B cell and CTL epitopes of DENV-2. The potential association between prolonged viremia and higher ability for immune evasion in DENV-2 patients was further corroborated with the observation of poorer HLA-I binding affinity in CTL epitopes observed in NS2a sequences retrieved from patients with >5 days of illness, compared to those with ≤5 days. This is the first report from central India revealing circulation of all DENV serotypes and high prevalence of co-infection with multiple serotypes. We also observed prolonged viremia upon DENV-2 infection, which could be potentially associated with its superior immune evasion potential.