_______________________________________________________________________________________________________________________________ OA Maced J Med Sci. 2015 Jun 15; 3(2):209-214. 209 ID Design 2012/DOOEL Skopje Open Access Macedonian Journal of Medical Sciences. 2015 Jun 15; 3(2):209-214. http://dx.doi.org/10.3889/oamjms.2015.044 Basic Science Tumor-Associated Macrophage (TAM) and Angiogenesis in Human Colon Carcinoma Manal A. Badawi, Dalia M. Abouelfadl, Sonia L. El-Sharkawy * , Wafaa E. Abd El-Aal, Naglaa F. Abbas Pathology Department, Medical Division, National Research Centre, Dokki, Giza, Egypt Citation: Badawi MA, Abouelfadl DM, El-Sharkawy SL, Abd El-Aal WE, Naglaa F. Abbas NF. Tumor-Associated Macrophage (TAM) and Angiogenesis in Human Colon Carcinoma. OA Maced J Med Sci. 2015 Jun 15; 3(2):209- 214. http://dx.doi.org/10.3889/oamjms.2015.044 Key words: Adenomatous polyps; cancer colon; macrophages; angiogenesis; CD68; Factor VIII. * Correspondence: Prof. Sonia El-Sharkawy. National Research Center, Pathology, Dokki, Cairo 2478, Egypt. Primary E-Mail: elsharkawy60@hotmail.com Received: 27-Mar-2015; Revised: 15-Apr-2015; Accepted: 16-Apr-2015; Online first: 27-Apr-2015 Copyright: © 2015 Manal A. Badawi, Dalia M. Abouelfadl, Sonia L. El-Sharkawy, Wafaa E. Abd El-Aal, Naglaa F. Abbas. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Competing Interests: The authors have declared that no competing interests exist. Abstract AIM: This study aimed to clarify how macrophages affect prognosis in cancer colon and their association with tumor angiogenesis. MATERIAL AND METHODS: Forty four biopsies of colon carcinoma and 15 of benign adenomatous polyps were investigated for macrophages infiltration and microvessels density using immunohistochemistry and image morphometric analysis. Macrophages and blood vessels were stained immunohistochemically by CD68 and F-VIII markers respectively. The morphometric analysis was carried out on the immunohistochemically stained slides using the Leica Qwin 500 Image Analyzer. Both of macrophages infiltration and microvessels density were correlated with histological tumor grade, stage and lymph node metastases and were correlated with each others. RESULTS: Macrophage infiltration was significantly higher in malignant cases than in benign polyps. High macrophage infiltration and hypervascularity were significantly correlated with T- staging and lymph nodes metastasis. A significant correlation was found between macrophage infiltration and microvessels densitie in malignant tumors where hypervascularity was significantly correlated with high macrophages infiltration. CONCLUSION: The significant correlation between macrophage infiltration and tumor angiogenesis suggests an interaction between macrophages and cancer cells stimulating microvessels formation, tumor invasion and metastasis in colon cancer. We recommend that macrophages infiltration should be evaluated to investigate their clinical value in development of individualized therapeutic regimens for management of colon carcinoma. Introduction The tumor microenvironment encompasses a wide variety of cells including malignant and non- malignant populations. Non-malignant populations include stromal cells, an expanding vasculature, and a leukocyte infiltrate. Macrophages comprise the dominant portion of the leukocyte population [1]. Tumor-associated macrophages (TAMs), macrophages existing tumor microenvironment, were first described in the early 1980s [2, 3]. Till now, TAMs have been found to play dual functions, both positively or negatively affect tumor growth through interactions with the micro-environment, and these actions are tissue specific [4-6]. Macrophages exist in two distinct polarized states: one is the classically activated (M1) state and the other is the alternatively activated (M2) state. M1 macrophages possess antitumor activity, whereas M2 macrophages promote tumor invasion and metastasis [7, 8]. However, most TAMs have a M2-like phenotype. CD68 is a pan-macrophage marker frequently used as a marker for TAMs, and CD68 recognizes both tumoricidal M1 and anti-inflammatory M2 macrophages [9, 10]. The vast majority of studies with numerous tumor types, including follicular lymphoma [11], gastric carcinoma [12], pancreatic cancer [13] and thyroid carcinoma [14] show that the presence of TAM in the tumor microenvironment is associated with a worse prognosis, some studies claim the opposite [15]. The specific role of TAMs in colon cancer is more