Physical biology in cancer. 1. Cellular physics of cancer metastasis.

One of the major challenges in cancer research today is developing new therapeutic strategies to control metastatic disease, the spread of cancer cells from a primary tumor to seed in a distant site. Advances in diagnosis and treatment options have increased the survival rate for most patients with local tumors; however, less progress has been made in treatment of disseminated disease. According to the SEER Cancer Statistics Review, 1975-2010, in the case of breast and prostate cancers, only one in four patients diagnosed with distant metastatic disease will survive more than five years. Current research efforts largely focus on identifying biological targets, such as specific genes and signaling pathways that drive two key steps of metastasis, invasion from the primary tumor and growth in the secondary site. On the other hand, there are phenotypic traits and dynamics in the metastatic process that are not encoded by single genes or signaling pathways but, rather, a larger system of events and biophysical characteristics. Connecting genomic and pathway investigations with quantitative physical phenotypic characteristics of cells, the physical microenvironment, and the physical spatiotemporal interactions of the metastatic process provides a stronger complementary understanding of the disease.