Nanotechnology and tumor microcirculation.

Though much progress has been made in the development of anti-tumor chemotherapeutic agents, refractoriness is still a major clinical difficulty because little is known about the non-autonomous mechanisms involved. Abnormal capillary structures in tumors, for example, are well documented, but a thorough characterization of microcirculation, including functional consequences with particular regard to drug delivery and intratumor accumulation, is still required for many kinds of tumor. In this review, we highlight how use of synthesized nanoparticles, themselves a product of emerging nanotechnology, are beginning to open up new perspectives in understanding the functional and therapeutic consequences of capillary structure within tumors. Furthermore, nanoparticles promise exciting new clinical applications. I also stress the urgent necessity of developing clinically relevant tumor models, both in vivo and in vitro.