According to the American Cancer Society, breast cancer is the most common cancer in women in the United States. Every 1 in 3 females are diagnosed with over 300,000 new cases of breast cancer each year. Breast cancer typically occurs in middle-aged to older women and is atypical for women under 45. Like all cancers, individuals can live a healthy lifestyle and reduce their risk of breast cancer, however, prevalence still occurs. In many cases, breast cancer is hereditary caused by mutations passed down to the child.
Unfortunately, there is no cure and over 40,000 women die annually, as a result of breast cancer. However, early detection and advanced technology has improved treatment over the last few decades. Currently, the standard of care for most stages of breast cancer includes tumor resection and high dose of chemotherapy or a regimen of combination therapy. Thus, many patients have a high 5-year survival rate. However, later stages of breast cancer and more aggressive subtypes are difficult to treat as tumors can evolve to resist therapy. Although, the advent of combination therapy, particularly with chemotherapy and immunotherapy, has improved treatment outcomes in patients, not all tumors respond. Scientists are working to learn more about these un-responsive cancers and how to enhance current treatments.
A recent study in Nature Communications, by Dr. Pauliina Munne and others, provides insight into why some patients with breast cancer do not respond to therapy. Munne is a scientist in the Translational Cancer Medicine Program at the University of Helsinki. Her work focuses on the immune response in breast cancer. Specifically, her team looks for biomarkers to target and improve standard-of-care therapy for breast cancer patients.
Immunotherapy is a more recent form of cancer treatment, which redirects the immune system toward the tumor. Under optimal tumor conditions, cancer cells secrete proteins and molecules to promote tumor proliferation and spread throughout the body. The cancer generates a favorable environment that suppresses the immune system around it. Immunotherapy reactivates that immune system to recognize and target the tumor.
Munne and her team used a series of laboratory techniques and computer analyses to determine that immunotherapy response is not only dictated on chemical signaling within the tumor, but also on the stiffness of tumor tissue. After analyzing patient samples, soft tissue plays a crucial role in the tumor microenvironment by allowing cancer cells to ‘hide’ from immune cells. Further investigation found that soft tissue tumors were more likely to metastasize since the cells change their morphology and function to spread to distal tissue locations. This is very interesting because stiff breast tissue is associated with an increased risk of breast cancer. Therefore, this discovery can have major implications on current treatment.
Munne and others have discovered that soft tissue can contribute to unresponsive therapy outcomes. This discovery can now help physicians better identify patients that would respond to specific therapies. A different approach to selecting for cancer treatments would improve outcomes and minimize burden on patients. Consequently, this observation has the potential to improve personalized medicine and treat patients with aggressive forms of breast cancer.
Study, Nature Communications, Pauliina Munne, University of Helsinki