Injecting antibodies and T cells with cancer stem cells may signal a new paradigm for anticancer immunotherapy, according to a recent study.
“This is a major breakthrough in immunotherapy research, because we were able to use purified cancer stem cells to generate a vaccine, which strengthened the potency of antibodies and T cells that selectively targeted cancer stem cells,” said lead investigator Qiao Li, PhD, Research Assistant Professor, Department of Surgery, University of Michigan, Ann Arbor.
Cancer stem cells, which differ from embryonic stem cells, remain present after chemotherapy or radiation treatment, and ultimately resistant to such therapy. Some scientists suggest that these cells are unique in regenerating tumors that lead to disease relapse. Destroying these cells may be a new way of preventing recurrence.
Li and colleagues prepared a vaccine using cancer stem cells from 2 immunocompetent mouse models. “We found that these enriched cancer stem cells were immunogenic and far more effective as an antigen source compared with the unselected tumor cells normally used in previous immunotherapy trials,” said Dr Li. “When antibodies were primed with cancer stem cells, they were capable of targeting cancer stem cells and conferring antitumor immunity.”
Enriched cancer stem cells were effective as an antigen source in inducing antitumor immunity. In addition, cytotoxic T lymphocytes harvested from vaccinated cancer stem cells were able to kill the cancer stem cells in vitro. Ning N, et al. Cancer Res. 2012;72:1853-1864.
