The head and neck squamous cell carcinoma (HNSCC) transcriptome has been profiled extensively, nevertheless, identifying biomarkers that are clinically relevant and thereby with translational benefit, has been a major challenge. The objective of this study was to use a meta-analysis based approach to catalog candidate biomarkers with high potential for clinical application in HNSCC. Data from publically available microarray series (N = 20) profiled using Agilent (4X44K G4112F) and Affymetrix (HGU133A, U133A_2, U133Plus 2) platforms was downloaded and analyzed in a platform/chip-specific manner (GeneSpring software v12.5, Agilent, USA). Principal Component Analysis (PCA) and clustering analysis was carried out iteratively for segregating outliers; 140 normal and 277 tumor samples from 15 series were included in the final analysis. The analyses identified 181 differentially expressed, concordant and statistically significant genes; STRING analysis revealed interactions between 122 of them, with two major gene clusters connected by multiple nodes (MYC, FOS and HSPA4). Validation in the HNSCC-specific database (N = 528) in The Cancer Genome Atlas (TCGA) identified a panel (ECT2, ANO1, TP63, FADD, EXT1, NCBP2) that was altered in 30% of the samples. Validation in treatment naïve (Group I; N = 12) and post treatment (Group II; N = 12) patients identified 8 genes significantly associated with the disease (Area under curve>0.6). Correlation with recurrence/re-recurrence showed ANO1 had highest efficacy (sensitivity: 0.8, specificity: 0.6) to predict failure in Group I. UBE2V2, PLAC8, FADD and TTK showed high sensitivity (1.00) in Group I while UBE2V2 and CRYM were highly sensitive (>0.8) in predicting re-recurrence in Group II. Further, TCGA analysis showed that ANO1 and FADD, located at 11q13, were co-expressed at transcript level and significantly associated with overall and disease-free survival (p<0.05). The meta-analysis approach adopted in this study has identified candidate markers correlated with disease outcome in HNSCC; further validation in a larger cohort of patients will establish their clinical relevance.

Objective The purpose of this study was to determine association between cancer stem cells (CSCs) and their niche with progression of oral potentially malignant lesions. Materials and Methods Patients with histologically confirmed oral potentially malignant disorders, stratified into high/low risk lesions based on the degree of dysplasia and oral cancer were included in this study. Immunohistochemical profiling of markers of CSCs (CD44), endothelial cells (CD31) and CSC-vascular niche cross-talk (CXCR4 and SDF1) were carried out. Statistical analysis was performed to correlate the relationship of markers with histopathology grade (ANOVA, and χ2 test, unpaired t test) using GraphPad InStat v3.06. Results The study included 550 samples (349 patients) and analysis showed progressive increase in expression levels of CSC and its niche markers with increase in grade of dysplasia as compared to the normal cohort (p<0.05). Co-expression analysis revealed that, in comparison to the normal cohort, a larger percentage of patients showed increased expression of CD31 and CD44 (CD31high/CD44high; p<0.05) and of CXCR4 and SDF1 (CXCR4high/SDF1high; p=0.04), suggesting an association of the CSCs and the vascular niche. Further, distribution of patients with CD44high/CXCR4high (p<0.05) and CD31high/SDF1high (p=0.01) was significantly increased in the high-risk group (18%), suggesting a correlation between CD44+/CXCR4+ cells, the vascular niche and progression of oral dysplastic lesions. Conclusion The increased expression of CSCs, the vascular niche and their cross talk markers are associated with increase in severity of dysplasia suggesting their role in the progression of oral potentially malignant lesions and may hence be used in identifying high-risk OPMD.

Background and Objectives:Oral squamous cell carcinoma (OSCC) is one of the most common head and neck carcinomas and corresponds to 95% of all oral cancers with an increasing morbidity and mortality. Its prognosis is affected by several clinicopathologic factors, one of which is pattern of invasion (POI). The histological features of OSCC may differ widely, but there is general agreement that the most useful prognostic information can be deduced from the invasive front of the tumor. In this retrospective study, our aim was to compare the POI, the status of connective tissue and the status of inflammation at the tumor–host interface in primary and recurrent (secondary) OSCC and test the validity of POI, to serve as a potential marker to assess the prognosis of the patient.Materials and Methods:Differentiation of tumors, POI, status of connective tissue and inflammation was assessed in 168 cases of primary and recurrent cases of OSCC.Statistical Analysis:Fisher's exact test was used to determine the statistical significance and P < 0.05 was considered to be statistically significant.Results:Our study showed that majority of the primary and secondary tumors were well differentiated, 117 [95.9%] and 34 [73.9%], respectively. Predominant POI in the primary and secondary tumor group was Pattern II and least was Pattern V. Worst pattern in primary tumor and highest distribution was seen for Pattern III (53.3%), and least for Pattern V (0.00%). In secondary tumors, the predominant worst pattern was Pattern IV (50.0%) and least distribution was seen for Pattern I (0.00%). Connective tissue status for both primary and secondary tumors showed the predominance of loose type (85.2% and 79.2%) and least was variable type (0.8% and 0.6%), respectively. Status of inflammation in the primary tumor group showed a predominance of moderate grade of inflammation (50.0%) and very mild grade of inflammation (6.6%) was the least type. In the secondary tumor group, moderate grade (43.5%) of inflammation was predominant and very mild grade (5.4%) was the least. All the parameters showed a statistically significant difference on the application of Fisher's exact test between the two groups.Conclusion:Our study showed that POI could serve as an individual prognostic marker irrespective of the histologic differentiation of tumor. Tumor desmoplasia could be considered as an important reflection of the tumor-host interaction, especially in aggressive cancers. Host immune defense, especially tumor infiltrating lymphocytes must be noted as critical factors related to survival rate in OSCC patients. Assessment of mentioned parameters may lead to sound prognostic assessment and appropriate treatment planning thus reducing the possibility of recurrence or relapse. Hence, the parameters evaluated in our study could serve as independent or interdependent prognostic markers.

Resistance to chemotherapy leading to poor outcome and survival remains a challenge for developing strategies for therapeutic interventions in all types of cancer, including head and neck cancer. In vitro chemoresistant cell line models are an indispensable resource towards delineating the mechanisms involved in drug resistance/response and for the development of novel drugs. Current treatment for head and neck cancer includes chemotherapy with cisplatin, docetaxel and 5-fluorouracil (5-FU) and the response rates to these drugs in patients is 60-80%. The present study aimed to generate head and neck cancer triple drug-resistant cell lines in an effort towards elucidating the mechanisms underlying chemoresistance and providing a resourceful tool for drug design. Using two head and neck squamous cell carcinoma cell lines, Hep-2 (larynx) and CAL-27 (oral cavity), the present study sequentially exposed these cells to increasing concentrations of the combination of docetaxel, cisplatin and 5-FU (TPF) to generate triple drug-resistant cells, termed Hep-2 TPF resistant (TPFR) and CAL-27 TPFR. The effect of the drug treatments on the cell viability, apoptosis, cell cycle and the expression of genes associated with multidrug resistance were analyzed in the parental cells and drug-resistant counterparts.