CAR T-cell therapy has shown to be effective in mice with ovarian cancer, offering new hope to patients who require effective treatment.
CAR T-cell therapy is a new type of immunotherapy that involves extracting a patient’s immune cells (known as T cells) from the blood and injecting them in a laboratory with a new gene that specifically attacks a molecule called a chimeric antigen receptor (CAR) on the surface of the tumour cells. When returned to the patients, the T cells are more aggressive and attack the cancer cells better.
“This therapy is currently available for patients with blood cancer, and we want to investigate if we can use the method to treat ovarian cancer,” said the study’s joint last author Isabelle Magalhaes, a docent at the Department of Oncology-Pathology at Karolinska Institutet. “Despite many improvements to the available therapy, the prognosis for women with ovarian cancer is still poor.”
What are the current treatment options for ovarian cancer?
Current treatment options for ovarian cancer depend on various factors, including:
- The size and type of ovarian cancer you have,
- Where the cancer is,
- if it has spread,
- and your general health.
The main treatments are surgery and chemotherapy. Other treatments include targeted medicines and hormone treatments.
The type of surgery depends on the cancer and how its spreads. Ovarian cancer is more treatable if its diagnosed early. Surgery can be used to remove both ovaries and the fallopian tubes, and the cervix and the womb. Chemotherapy is a medicine that kills cancer cells. It can be given before and after surgery or used on its own.
Introducing CAR T-cell therapy as an ovarian cancer treatment
Many ovarian tumours contain mesothelin, and the researchers wanted to test three types of CAR molecules programmed to attack this particular protein. They exposed the ovarian cancer cells to the programmed CAR T-cells in test tubes and conducted several experiments on mice.
All three CAR T-cells significantly prolonged the lives of the mice with cancer compared to those in the control group, with the type called M1xx CAR T-cells proving to be most effective. The mice that were injected with T-cells that express that particular molecule saw a reduction in tumour size and lived even longer than others. Several of the mice were even cured. This indicates the important role of CAR T-cell therapy in cancer care.
“In several mice, there were no tumour cells left that we could detect, and the effect lasted just over three months after the treatment started. This is evidence that immunotherapy involving CAR T cells that attack the mesothelin protein is a promising one for ovarian cancer,” said Professor Mattsson.
“Hopefully, this discovery will pave the way for a clinical study,” he said. “Our goal is to predict the optimal conditions for producing CAR T cells able to infiltrate and attack the tumour and survive in the bodies of women with ovarian cancer.”