PROVIDENCE, R.I. [Brown University] A new study shows that adipose-derived human stem cells, which can become vital tissues such as bone, may be highly resistant to the common chemotherapy drug methotrexate (MTX). The preliminary finding from lab testing may prove significant because MTX causes bone tissue damage in many patients.
MTX is used to treat cancers including acute lymphoblastic leukemia, the most common form of childhood cancer. A major side effect of the therapy, however, is a loss of bone mineral density. Other bone building stem cells, such as bone marrow derived stem cells, have not withstood MTX doses well.
"Kids undergo chemotherapy at such an important time when they should be growing, but instead they are introduced to this very harsh environment where bone cells are damaged with these drugs," said Olivia Beane, a Brown University graduate student in the Center for Biomedical Engineering and lead author of the study. "That leads to major long-term side effects including osteoporosis and bone defects. If we found a stem cell that was resistant to the chemotherapeutic agent and could promote bone growth by becoming bone itself, then maybe they wouldn't have these issues."
Stem cell survivors
Originally Beane was doing much more basic research. She was looking for chemicals that could help purify adipose-derived stem cells (ASCs) from mixed cell cultures to encourage their proliferation. Among other things, she she tried chemotherapy drugs, figuring that maybe the ASCs would withstand a drug that other cells could not. The idea that this could help cancer patients did not come until later.
In the study published online in the journal Experimental Cell Research, Beane exposed pure human ASC cultures, "stromal vascular fraction" (SVF) tissue samples (which include several cell types including ASCs), and cultures of human fibroblast cells, to medically relevant concentrat
|Contact: David Orenstein|