Feinberg researchers’ method may help cure cancer in mice

Ben Figa

A team of Northwestern researchers at the Feinberg School of Medicine has developed a new technique that may help cure mice of cancer, according to a Dec. 15 scientific journal.

Cancer Research magazine reported that urology Prof. Chung Lee and his colleagues have discovered a powerful new gene therapy technique that causes the immune system to attack cancer cells. The treatment must undergo further development and pre-clinical trials before it receives approval for human testing.

Cancer cells block white blood cells through immunosuppressors, one of which is called TGF-beta. The NU researchers are trying to determine if a newly discovered gene could cause white blood cells to outsmart the TGF-beta immunosuppressor.

“All cancerous cells produce TGF-beta — it’s like a firewall,” said Victoria Liu, a researcher in Lee’s lab. “Immune cells will run into the firewall and be bumped back. We use a gene that causes the immune cell to be insensitive to TGF-beta, so the immune cell can go through the firewall.”

The experiment involved inserting a mutated gene into bone marrow cells. Those cells were then transplanted into mice.

Mice in the experimental group that received an injection of melanoma achieved a 70 percent survival rate and virtually were free of widely spread lesions in their lungs. Mice injected with prostate cancer after the treatment fared even better, achieving an 80 percent survival rate.

All mice that didn’t receive the treatment died from cancer after being injected with melanoma or prostate cells. Despite those telling statistics, researchers cautioned that they must be satisfied with pre-clinical testing on animals before pursuing the first phase of human testing.

“We are working on the pre-clinic study right now, and it may take a couple more years to go to a Phase I human trial,” Liu said.

The scientists currently are focused on identifying the cells needed for immune response.

“We don’t know which immune cells to make insensitive to TGF-beta,” Lee said. “We have made the entire bone marrow population insensitive … but we want to know which cells are necessary.”

Further research will include applying the gene therapy to mice who develop prostate cancer spontaneously and correcting the gene inducible so it can be activated and deactivated.

Lee and other researchers from the urology department said they hope their work will continue to produce notable results.

“All of the researchers want to cure cancer,” Liu said. “However, the road is really bumpy. Hopefully our lab can contribute to the big picture of curing cancer.”