Sickle Cells Deliver Chemotherapy in New Cancer Treatment
Drug-loaded cells burst inside tumors (October 8)
By loading sickle red blood cells with cancer-fighting drugs and programming them to burst open in tumors, scientists have found a way to deliver large amounts of chemotherapy into oxygen-starved tumors that have proven difficult to treat in humans.
The new method, described in the October issue of the Journal of Controlled Release, exploits the tendency of jagged, crescent-shaped sickle cells to target and stick to the walls of tumor blood vessels. When programmed with photoradiation, the drug-loaded sickle cells burst open in the tumor and delivered fourfold more drug to breast cancers in mice than did similarly treated normal red blood cells and free drug. This method could be used to deliver numerous chemotherapeutic agents to a broad spectrum of human tumors, the authors say.
The new findings were reported by investigators at the Jenomic Research Institute in Carmel, California, and at the University of Florida.
In the study, sickle cells were loaded with drugs and programmed to burst open 15 hours after injection, when most of the sickle cells had accumulated in the tumors. At this critical time point, the ruptured sickle cells spilled their drug cargo on the tumor cells, achieving drug levels in tumors that exceeded those of free drug and similarly treated normal red blood cells.
According to the researchers, the new treatment can be used in all humans, not just those with sickle cell anemia, since the sickle cells can be obtained from sickle cell precursor cells grown in the laboratory. Journal editor Kwon Park suggested that sickle cells may be more flexible than nanoparticles for delivering cancer-fighting drugs to oxygen-deprived tumors that are hard to treat in humans.
Source: PR Newswire; October 8, 2013.