"For decades, we've had cancer vaccines that fail to work, and we haven't really understood why," said Dr. Lynn Schuchter, a medical oncologist at the University of Pennsylvania and chair of the cancer research committee for the American Society of Clinical Oncology.
But recent advances in understanding and harnessing the immune system's power could be changing that, according to Schuchter, who was not involved in the new study.
"These are pretty dramatic results in the mouse model [of human cancers]," she said. "Studies like this are paving the way for effective vaccine approaches."
However, animal research does not always pan out in human trials.
The researchers, led by Dr. Ugur Sahin, of Johannes Gutenberg University in Mainz, Germany, used an approach that targets specific mutations in a given tumor.
The mutations unique to cancer cells are an "ideal" target for vaccines, according to Sahin's team. That's because the mutations are absent in healthy cells, and could stimulate the immune system to recognize tumors as foreign invaders and attack them.
However, since each person's cancer has a unique set of mutations, scientists are working toward customized vaccines -- tailored to target an individual patient's tumor.
Earlier this month, researchers reported initial results on just such a therapy. They developed personalized vaccines for three people with advanced melanoma, the deadliest form of skin cancer.
In each case, the vaccine triggered an increase in T-cells that could recognize the patient's cancer cells -- though the researchers stressed it's not yet clear whether the approach can actually beat back melanoma and extend people's lives.
The vaccines used in the current study are molecularly different from those in the melanoma trial, explained Dr. Alexandra Snyder Charen, an oncologist and immunotherapy researcher at Memorial Sloan Kettering Cancer Center, in New York City.
The latest approach could potentially "stimulate the whole immune system,