Abstract
Although it is well recognized that the tumor microenvironment plays a key role in regulating tumor progression, the mechanisms through which this occurs need to be defined. Current international research activities toward defining the role of the tumor microenvironment in cancer progression were the subject of the first Tianjin Forum on Tumor Microenvironment held at Nankai University in Tianjin, China, July 2 to 4, 2010. The importance of variety of processes, such as inflammation and angiogenesis, in the role of tumor progression was described for multiple tumor types including breast, prostate, and hepatic cancers, as well as the process of bone metastasis. Identification of novel signaling pathways that impact both angiogenesis and bone remodeling were presented. Several themes emerged from this meeting, such as: (i) tumor cells modify the microenvironment to enhance their own survival and progression; (ii) targeting host factors, in addition to targeting tumor cells, will have important therapeutic effects; and (iii) host cells distribution within the tumor has both prognostic and therapeutic significance. Several priorities for future research were defined including use of a systems biology approach to define the role of host factors in tumor progression, to define the importance of targeting both arms of the bone remodeling process for therapy of bone metastasis, and to determine how different cell subsets contribute to microenvironment-mediated regulation of tumor progression.