Biology of liver metastases.

A primary goal of cancer research is an increased understanding of the molecular mechanisms mediating the process of cancer metastasis. Analyses of colon cancer cells (the seeds) and the microenvironment (the soil) have increased our understanding of the biologic mechanisms mediating metastasis formation. Insight into the molecular mechanisms regulating the pathobiology of colon cancer metastasis, as well as a better understanding of the interaction between the metastatic cell and the host environment (including the vasculature), should provide a foundation for new therapeutic approaches. To the clinician, it is readily apparent that by the time metastases form, most steps in the metastatic cascade have completed. Therefore, therapy to down-regulate or interrupt the last stages of metastasis, proliferation and angiogenesis as well as mechanisms to disrupt cell survival signals seems the most promising areas of investigation.