PATHOBIOLOGY IN FOCUS Experimental approaches to the study of cancer–stroma interactions: recent findings suggest a pivotal role for stroma in carcinogenesis

An increasing body of research indicates that stroma surrounding cancer cells plays an important role in the development and subsequent behavior of the tumor. Studies using a wide range of techniques, including stromal cell isolation, modification of stromal-specific gene expression, and recreation of specific microenvironment conditions in culture, have demonstrated that stroma can promote cancer and that the expression patterns within the stroma can influence clinical outcome. Major hurdles in the study of the cancer stroma revolve around the cellular complexity of the tumor microenvironment, both in modeling the microenvironment and discovering/isolating pure populations of stromal cell types.