Dr. Mark Noble, professor of Biomedical Genetics and director of the University of Rochester Medical Center Stem Cell and Regenerative Medicine Institute, and colleagues announced the confirmation of “chemo brain” produced by the breast cancer drug tamoxifen and the discovery of a drug already in clinical trials that eliminates the “chemo brain” effects of tamoxifen in the Sept. 17, 2013, edition of the Journal of Neuroscience.
“Chemo brain” describes the loss of mental acuity, memory loss, and loss of concentration that has been reported by women taking tamoxifen as a part of breast cancer therapy.
The researchers found that 75 percent of oligodendrocyte-type 2 astrocyte progenitor cells (O-2A/OPCs) that produce nerve myelin sheaths were killed in 48 hours after the administration of medicinally equivalent doses of tamoxifen to mice.
A search of a database of drugs in clinical trials found a substance known as AZD6244 that eliminated the death of O-2A/OPCs in mice.
The results are of consequence in protecting women with breast cancer from the side effects of tamoxifen and preventing the complications of depression, job loss, and other debilitating events that are the result of tamoxifen induced “chemo brain.” Secondarily and potentially as important, the discovery opens the door for testing and approval of tamoxifen type drugs that address other types of cancer and avoid the mental side effects of tamoxifen.