Stem cells morph into cancer busters

PENN STATE (US) — Adult stem cells from mice converted to antigen-specific T cells may lead to a simpler, more efficient way to use the body’s immune system to fight cancer.

“Cancer immunotherapy is a promising method to treat cancer patients,” says Jianxsun Song, assistant professor of microbiology and immunology at Penn State.

“Tumors grow because patients lack the kind of antigen-specific T cells needed to kill the cancer. An approach called adoptive T cell immunotherapy generates the T cells outside the body, which are then used inside the body to target cancer cells.”


Because it is complex and expensive to expand T cell lines in the lab, researchers have searched for ways to simplify the process. Song and colleagues used induced pluripotent stem (iPS) cells, which are adult cells that are genetically changed to be stem cells.

“Any cell can become a stem cell,” Song explains. “It’s a very good approach to generating the antigen-specific T cells and creates an unlimited source of cells for adoptive immunotherapy.”

By inserting DNA, the mouse iPS cells are changed into immune cells that are injected into mice with tumors. After 50 days, 100 percent of the mice in the study were still alive, compared to 55 percent of control mice, which received tumor-reactive immune cells isolated from donors.

Findings are reported in the journal Cancer Research.

A limitation of this potential therapy is that it currently takes at least six weeks for the iPS cells to develop into T cells in the body. Also, potential side effects need to be considered. iPS cells may develop into other harmful cells in the body.

Researchers are now studying how to use the process in human cells.

The study was funded through the Pennsylvania Department of Health using Tobacco Settlement Funds, the W.W. Smith Charitable Trust, and the Melanoma Research Foundation.

More news from Penn State: