Tumor Microenvironment

The concept that tumor-host interactions are crucial in tumor progression is now well-accepted. In fact, the English Surgeron Stephen Paget first proposed the “seed and soil” hypothesis in 1889, which states that cancer cells (“the seeds”) metastasize systemically and grow best in the most tumor-promoting host organs or the most “fertile soil.”
In this context, tumor cells corrupt or transform their microenvironment in order to generate new blood vessels to support their oxygen requirements. Closely linked to this idea, we and others have begun to view cancer as a “parasitic disease” that “steals” energy-rich metabolites from the host microenvironment.
The tumor stroma, which is composed of fibroblasts, adipocytes, endothelial cells and macrophages, lies in extremely close proximity to cancer cells, and can directly promote tumor growth. Recent studies indicated that the tumor microenvironment can help determine clinical outcome in human cancer patients and may also confer drug-resistance and treatment failure, leading to tumor recurrence and metastasis.
Thus, a better understanding of the tumor microenvironment is required for us to achieve the goals of personalized medicine, with more effective individualized patient based diagnostics and therapeutics.