12 Jul Does Stiff Breast Tissue Increase Breast Cancer Risks?
Scientific findings have demonstrated a significant association between breast tissue stiffness and cancer risks. For example, in a reported study by the Minkin lab in 2014, their studies showed breast tissue stiffness led to higher risks of breast cancer in animal models, as well as risk prediction since tissue stiffness can increase the invasion and progression of cancers.1 Compared to soft low-dense breast tissue, cells found in stiff breast tissue behave much differently. Stiffer breast tissue leads to a higher number of cells, which in return increases the amount of collagen production, a primary culprit that stiffens tissue.
- Thus, this highly dense tissue microenvironment is proven to influence cell growth, survival, motility, differentiation, and even breast cancer development.
Clinical observations were in agreement with these findings that reported women with dense breast tissue actually have a 4-6 fold greater risks of developing breast cancer.2
Minkin’s research involving animal models may offer an insightful understanding of the mechanism as to why dense breast tissues may increase breast cancer risks, which is in agreement to known clinical data. Yet, how well can we actually correlate cancer research discoveries from animal tissue models to real-life human breast cancer morphology? Can we reliably use these research results on understanding breast cancer morphologies and tumor development in animal models to generate similar theories and an insightful understanding as to why women with denser breast tissue have higher risks to develop breast cancer?
The ability of doctors and scientists to examine whether there are any correlations between breast tissue stiffness and cancer risks by using animal versus human tissue models has been widely debated. Animal and human tissue and cells behave rather differently from each other and can exhibit contrasting mobility patterns and growth behaviors. Performing research studies in animal tissue models may provide some insight and cancer metastasis in a less expensive manner while offering researchers with more control to manipulate tumor development conditions. However, this may also present additional challenges when trying to predict similar conclusions in human tissue models.
In a recent 2018 study published in the journal, Biomaterials, scientists from the University of Notre Dame used fabricated human tissue models to understand the mechanism between cancer cells with connective breast tissue and its influence on tumor growth and metastasis.3 Using this model, they were able to control the stiffness of the tissue in order to imitate human breast tissue both under healthy and cancerous physiological conditions. Their observations were consistent with previous findings from other research studies which also reported stiffer breast tissue enables cancer cells to form since it can manipulate and mobilize more easily within the surrounding environment and other cells.
- However contrasting to other previous research findings, these the Notre Dame scientists believe that fat cells in breast-tissue actually influences tissue stiffness, a conclusion that slightly contrasted from similar research performed in animal tissue models.
This research observation also was in agreement with clinical data that correlated obesity to be associated with higher risks of cancer whereas most overweight women had a 58% greater increase in developing breast cancer.4
Scientists and doctors are constantly optimizing and developing new models, both animal, and humans, that will enable them to have the appropriate tools to better understand cancer morphology and tumor development. Yet, this continues to be rather challenging since there are many factors that must be considered that can influence tumor growth in real-life cancer patients.