The answer to this question is yes. I am not suggesting that mushrooms can cure cancer but they can have positive impact on helping the immune system fight cancer. How is this possible you ask? Well, to answer that question you need to understand how tumor cells promote tumor development. Tumor cells release inflammatory cell signaling molecules called cytokines such as transforming growth factor-β (TGF-β) and interleukin-10 (IL-10) which transforms macrophages into a type that promotes cancer. There are two types of macrophages: M1 and M2. M1 is characterized by resisting the development of tumors and M2 is characterized by the development of tumors. As with tumor cells, M2 macrophages also secrete transforming growth factor-β (TGF-β) and interleukin-10 (IL-10) and this adds fuel to the fire. This leads to tumor cells evading detection by the immune system and spreading of tumors (metastases). So, is there a way for the body to create an anti-tumor environment full of M1 macrophages? The answer is yes and this is where mushrooms can help. It turns out that mushrooms contain a polysaccharide called beta-glucan which can change the tumor environment by making more M1 macrophages.