Cancer stem cell and its niche in malignant progression of oral potentially malignant disorders.

OBJECTIVE: The purpose of this study was to determine association between cancer stem cells (CSCs) and their niche with progression of oral potentially malignant disorders. 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 disorders and may hence be used in identifying high-risk OPMD.

Combined surgery and radiation improves survival of tonsil squamous cell cancers.

OBJECTIVE: The study evaluated the addition of surgery (S) to radiation (RT) on survival of squamous cell carcinomas (SCC) of tonsillar-fossa (TF) in a modern cohort with similar epidemiology and treatment as current patients. STUDY DESIGN: Retrospective analysis utilizing Surveillance, Epidemiology, and End Results (SEER) Program data. RESULTS: For all stages combined TF patients who received S+RT had superior OS (p < 0.01) and DSS (p < 0.01). For each stage OS and DSS was superior for S+RT (p < 0.05). In multivariate analysis, HRs for OS were statistically significantly higher for TF patients (stage 2, 3, and 4) receiving RT alone (p < 0.001). MATERIALS AND METHODS: TF SCC patients treated with either S+RT or RT alone between 2004 and 2011 were examined (n = 6,476). Primary outcome measures included overall survival (OS) and disease specific survival (DSS). Cox proportional hazard ratios (HR) were estimated for patients treated with S+RT compared to RT alone. CONCLUSIONS: OS and DSS were superior for all stages combined and for stages 2, 3, and 4 in TF patients who received S+RT compared to RT alone.

Current state and future of photodynamic therapy for the treatment of head and neck squamous cell carcinoma.

Photodynamic therapy has shown promise in the treatment of early head and neck squamous cell carcinoma (SCC). In photodynamic therapy (PDT), a light sensitive drug (photosensitizer) and visible light cause cancer cell death by the creation of singlet oxygen and free radicals, inciting an immune response, and vascular collapse. In this paper, we review several studies that demonstrate the effectiveness of PDT in the treatment of early stage SCC of the head and neck, with some showing a similar response rate to surgery. Two cases are presented to illustrate the effectiveness of PDT. Then, new advances are discussed including the discovery of STAT3 crosslinking as a potential biomarker for PDT response and interstitial PDT for locally advanced cancers.