Pitt Researchers Use Gene Editing To Target Highly Aggressive Cancers

May 15, 2017

University of Pittsburgh researchers have found a gene editing technique that could be used to treat aggressive forms of cancer.

Using CRISPR-Cas9 genome editing technology, researchers shrunk tumors in mice by up to 30 percent by removing specific “fusion genes” that are often present in cancer cells and replacing them.

Fusion genes occur when two previously separate genes merge and produce abnormal proteins that can cause cancer.

Pitt pathology professor Jian-Hua Luo and his team had previously identified eight fusion genes that are linked to prostate cancer.

“(We were) trying to … understand why some of the prostate cancers are aggressive and some of them are not,” Luo said.

While the tumors in the mice did not disappear completely using the experimental therapy, Luo said there might be a way around that.

“This could be improved if we apply a multiple targeting strategy,” Luo said. “For example, in one cancer cell you have four or five fusion genes … so each fusion gene has about a 21 to 35 percent chance of being hit, so that improves quite significantly if multiple targeting is being applied.”

Luo said, due to funding restrictions, his team focused on just one particular fusion gene, but estimated that there might be 6,000 different types of fusion genes present in cancer cells.

He said one advantage of his technique is that it is highly adaptable; any type of fusion gene could be targeted. Though he noted that less aggressive cancers tend to have fewer fusion genes.

“In fact, the more aggressive the type of cancer, the better,” Luo said.

Luo said gene editing has advantages over traditional cancer treatments such as chemotherapy and radiation. He said they did not observe any negative side effects in the mice during the experiment, because the technique only targeted cancer cells and not healthy cells.

Chemotherapy and radiation target proteins produced by genes, whereas gene editing targets the genes themselves.

“Other types of cancer treatments target the foot soldiers of the army,” said Luo. “Our approach is to target the command center, so there is no chance for the enemy’s soldiers to regroup in the battlefield for a comeback.”

Luo said the next step is to run a clinical trial, but said it could be two to three years before that begins.