A recent discovery by stem cell scientists at Cedars-Sinai may help make cancer treatment more efficient and shorten the time it takes for people to recover from radiation and chemotherapy.
Published in the journal Nature Communications, the study by Dr. John Chute and his team (and co-funded by CIRM) revealed a mechanism through which the blood vessels in the bone marrow respond to injury, such as from chemotherapy or radiation.
Each year, about 650,000 cancer patients receive chemotherapy in an outpatient oncology clinic in the United States.
When people receive radiation or chemotherapy as part of their cancer treatment, their blood counts plummet. It typically takes several weeks for these counts to return to normal levels. During this period patients are at risk for developing infections that may lead to hospitalization, disruptions in chemotherapy schedules, and even death.
Chute and his colleagues found that when mice receive radiation treatment, the cells that line the inner walls of the blood vessels in the bone marrow produce a protein called semaphorin 3A. This protein tells another protein, called neuropilin 1, to kill damaged blood vessels in the bone marrow.
When the investigators blocked the ability of these blood vessel cells to produce neuropilin 1 or semaphorin 3A, or injected an antibody that blocks semaphorin 3A communication with neuropilin 1, the veins and arteries in the bone marrow regenerated faster following irradiation. In addition, blood counts increased dramatically after one week.
“We’ve discovered a mechanism that appears to control how blood vessels regenerate following injury,” said Chute, senior author of the paper. “Inhibiting this mechanism causes rapid recovery of the blood vessels and blood cells in bone marrow following chemotherapy or irradiation.”
In principle, Chute said, targeting this mechanism could allow patients to recover following chemotherapy in one to two weeks, instead of three or four weeks as currently experienced.
Christina M. Termini, a post-doctoral scientist at the David Geffen School of Medicine at UCLA, was the first author of this study. Read the source press release here.