Expert to speak at GU on cancer vaccines that could be standard in next decade

Dr. Nora Disis has worked years to develop a breast cancer vaccine that teaches the body’s immune system to recognize and destroy breast cancer cells.

Director of the University of Washington Cancer Vaccine Institute, Disis will speak at 6:30 p.m. Wednesday at Gonzaga University on, “How Close Are We to a Breast Cancer Vaccine?”

The Seattle oncologist expects many cancer vaccines to become standard care in the next decade, but likely first for breast cancer . Breast cancer affects 1 in 8 women in the United States and caused 42,000 deaths in 2022.

“We now understand the type of immune response that we need to kill cancer, and it’s different from the type of immune response that we generate with infectious disease vaccines, which is generally an antibody response,” said Disis, named 2024 UW Medicine Inventor of the Year.

The UW-GU Health Partnership Next Generation Medicine talk is free at the Hemmingson Center and to live-stream, but registration is required. Disis plans to cover the latest cancer vaccine advances in the past eight years that have moved the work along rapidly.

“The type of immune response that we use for cancer vaccines is to generate what’s called a T Cell-immune response,” she said. “The second big breakthrough was when you create a vaccine, you have to immunize against something.

“For a long time, we didn’t know what to immunize against in different types of cancers. Now, hundreds of cancer immunogenic proteins have been identified. We can literally tailor-make a vaccine against specific types of tumors.”

Scientists recognize more about tumor-specific antigens, which are proteins or other molecules only found in cancer cells. Improved vaccine technologies also are paving ways to create safe vaccines more rapidly, she said, such as DNA-based or messenger RNA (mRNA) vaccines, the latter used for the first COVID-19 shots.

One goal is ensuring that a cancer vaccine can activate immune cells and train the body’s immune system to recognize cancer cells as dangerous. Disis said cancer vaccines are delivered as a shot, “like you go for your COVID or flu shot, but it’s not one time.”

“It’s like a shot in the arm once a month for three shots,” she added. “Then there are booster shots maybe every four to five months. With cancer patients, we’re still trying to figure out how long the booster shots need to go on, but they’ll probably have to get a booster shot after the initial vaccine regimen, maybe once a year.”

Many advanced clinical trials are showing promise, she said, including ones at the UW center investigating vaccines for breast and ovarian cancers.

“One of them is a vaccine directed against an antigen or immunogenic protein in a breast cancer called HER-2, responsible for about 30% of all breast cancers,” Disis said. “We have run several clinical trials that show that immunization or vaccines against HER-2 look very effective in preventing the disease from coming back in women who have more advanced HER-2-positive breast cancers.

Another vaccine called STEMVAC is directed at stem cells in cancer that have a tendency to be resistant to radiation and chemotherapy and metastasize early, she said. The idea is for the vaccine to train the immune system to recognize and kill these cells.

“We’re using that vaccine in a type of breast cancer called triple-negative breast cancer, which has a tendency to be a little more aggressive than other types of breast cancer,” Disis said.

A third promising vaccine, used following chemotherapy, targets a protein in ovarian cancer that causes it to spread in the abdomen. It shows promise in allowing patients to have longer survival without cancer recurrence.

She said most cancer vaccine clinical trials today target patients after chemotherapy and surgery in trying to keep the cancer from returning, but several trials are immunizing patients who never had cancer to prevent it.

It’s still too early to know vaccine implications for the BRCA1 and BRCA2 gene mutations that put women at high risk for breast and ovarian cancers. Disis hopes that doctors eventually can offer a vaccine to those patients.

Today, they’re often advised to get a double mastectomy or surgery to remove ovaries. Side effects include loss of estrogen and other protective hormones, with risks such as cardiovascular disease.

“I’d rather be able to offer a vaccine that if it won’t completely 100% protect you from the development of breast cancer,” Disis said. “Maybe it will protect you enough that we can push those radical surgeries to a point that would be closer to your menopause.”