A recent study investigated why immunotherapy for breast cancer is not as effective as a cancer treatment.
Despite the recent advancements in immunotherapy and the new era of personalized medicine to treat different forms of cancer, breast cancer has proven to be a difficult opponent for this new therapy. Previous trials have shown that immunotherapy for breast cancer is not as effective as it is for other cancers, such as melanoma.
When cancer occurs in the body, our immune system often fails to recognize cancer cells as abnormal. Immunotherapy is a type of cancer treatment that boosts your body’s natural defences and helps your immune system fight cancer. Immunotherapy drugs work by inactivating mechanisms cancer cells use to hide from the immune system, enabling the immune system to then attack and fight cancer.
A recent study by interdisciplinary researchers in the United States aimed to investigate further why immunotherapy is not as effective for treating breast cancer. They looked at data collected from over 1,000 breast cancer patients and their findings were recently published in PLOS ONE.
Breast cancer hides from the immune system
The researchers found that the problem lies in how breast cancer hides from the immune system. Breast cancer behaves differently to other cancers which respond well to current immunotherapy. They found breast cancer uses various evasion mechanisms to avoid detection, with some types even using a combination of ways to hide from the immune system. Biomarkers identified enabled the researchers to cluster patients into seven subgroups based on the immune evasion mechanism.
Knowledge is power. Utilizing this data to understand more about breast cancer tumors and how they work enabled oncologists to better treat breast cancer patients and guide their choice of treatment. Therefore, shedding light on the rationale behind the design of combination treatment plans, either with the more traditional therapies such as chemotherapy and radiation or with new immunotherapy drugs. Hence, identifying biomarkers in breast cancer which can help guide treatments may also enable researchers to design new potential immunotherapy drugs, which would allow these breast cancer patients to be included in clinical trials and benefit from a treatment that has previously proved to be elusive.
More studies needed to understand why only some patients respond to treatment
However, even though immunotherapy has been a massive breakthrough for cancer treatment, personalization of cancer treatments is not where it should be. With so much data being available to researchers, there is still a big gap in understanding why some patients respond to treatment, while others do not. Further studies utilizing this data is necessary to help understand more about why immunotherapy for breast cancer is not currently as effective as it is for some other forms of cancer.
Written by Lacey Hizartzidis, PhD
- Bou-Dargham MJ, Liu Y, Sang QA, Zhang J. Subgrouping breast cancer patients based on immune evasion mechanisms unravels a high involvement of transforming growth factor-beta and decoy receptor 3. PLoS One. 2018 Dec 4;13(12):e0207799.doi: 10.1371/journal.pone.0207799.
- FSU researchers identify ways breast cancer avoids immune system detection. EurekAlertwebsitehttps://www.eurekalert.org/pub_releases/2018-12/fsu-fri121818.php. AccessedJanuary 27, 2019.