ABSTRACT
Background: It is well established that chronic exposure to tobacco induces head and neck cancers but the exact etiopathogenesis is not known. Though studies have shown expression of TIMP1, EPS8 and AXL in cancers, their role in tobacco-induced cancers is not known. We aimed this study to evaluate the role of these molecules in oral and oropharyngeal squamous cell cancers (SCC). Materials and Methods: In this single institutional study, 31 patients of oral and oropharyngeal SCC with history of chewing tobacco were included. Smokers were excluded from the study. After informed consent biopsies were taken from affected and contralateral normal mucosa. Paraffin blocks were made and tissue microarray (TMA) were constructed using these blocks. Immunohistochemistry (IHC) for TIMP1, EPS8, AXL kinase was carried out on these tissue microarrays. The intensity of staining was scored from 0 to 3+, related to expression of each of the three molecules. Results: The expression of TIMP1, EPS8 and AXL kinase was significantly more in the cancerous mucosa versus non-cancerous mucosa (P = 0.000 in all three) in oral and oropharyngeal SCC exposed to chewing tobacco. Conclusion: Immunohistochemical expression of these molecular markers in oral and oropharyngeal SCC correlated with their molecular based studies. Significant IHC expression of TIMP1, EPS8 and AXL establishes their role in the pathogenesis of oral and oropharyngeal squamous cell carcinomas. Novel targeted therapies may be researched that can detect and target these molecules at an earlier stage of pathogenesis of these tumors.
ABSTRACT
Background: Human epidermal growth factor receptor 2 (HER2)/neuprotooncogene (neu) is a proven molecular prognostic marker in breast, ovarian, gastric, and ovarian cancers. In head-and-neck cancers, varied expression is documented and therefore its prognostic role is debatable. Aim of the Study: To find the rate of overexpression of HER2/neu in head-and-neck cancers and to understand its prognostic role by evaluating its association with nodal stage and overall stage of the patient. Methodology: A total of 70 surgically resected cases of head-and-neck cancers were evaluated for expression of HER2/neu by immunohistochemistry. Scoring was done according to the American Society of Clinical Oncologists/College of American Pathologistsguidelines for Her2/neu testing in breast cancer. Results: Of the 70 cases studied, 57 were of oral cavity and 13 were laryngeal squamous cell cancers and 14 (20%) were Her2/neu positive. On correlating the expression of HER2/neu in T1/T2 (41 cases) versus T3/T4 (27 cases), the P value was found to be 0.8273 which was statistically insignificant. Furthermore, no statistically significant difference in expression of HER2/neu was found in between node negative and node positive cases (49 vs. 19 cases, respectively), with P = 0.512. Conclusion: In the current settings, HER2/neu is not found to be a prognostic marker in head-and-neck cancers. Standard immunohistochemistry staining protocols need to be established like in breast cancers to aid uniform reporting and further evaluate the role of this important protooncogene in head-and-neck cancers.