Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 11 2016 08 15 846 852 Maryam Khalili Nazanin Mahdavi Assistant Professor, Department of Oral and Maxillofacial Pathology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Razieh Beheshti Fereshteh Baghai Naini 2016 04 13 2016 04 13 Objectives: Squamous cell carcinoma (SCC) is the most common malignant neoplasm of the oral cavity and a public health threat. Tumor progression is believed to be influenced by angiogenesis as well as tumor cell proliferation; however, the correlation of these two factors in tongue SCC still remains unclear. This study aimed to assess the correlation of these two factors in tongue SCC. Materials and Methods: Twenty-four paraffin block sections of tongue SCC were stained with monoclonal antibodies against CD105 and Ki-67. In order to assess the expressions of CD105 and Ki-67 to evaluate CD105 microvessel density (MVD), positively stained microvessels were counted in a predominantly vascular area (hot spot) in each specimen at ×400 magnification. The proliferation index was expressed as a percentage of Ki-67 positive cells. Data were analyzed by t-test and Pearson’s correlation coefficient (P<0.05). Results: The CD105 MVD was related to histological grading as well as Ki67 labeling index (LI; P= 0.045 and P=0.047, respectively). Both CD105 MVD and KI67 LI were unrelated to sex (P=0.41 and P=0.78, respectively) and age (P=0.20 and P=0.36, respectively) of the patients. No correlation was found between CD105 MVD and Ki67 LI (P=0.86). Conclusion: The mean CD105 MVD was significantly lower in poorly differentiated tumors. This finding suggests that CD105 MVD may serve as a valuable prognostic factor in tongue SCC. Absence of correlation between MVD and tumor cell proliferation indicates that these processes may be guided by unrelated mechanisms. https://fid.tums.ac.ir/index.php/fid/article/view/1179 https://fid.tums.ac.ir/index.php/fid/article/download/1179/844