Periods of fasting have been shown to reprogram the immune system’s natural killer cells to better fight cancer in a new study conducted with mice by researchers at Memorial Sloan Kettering Cancer Center (MSK). Fasting and other dietary regimens are being explored as potential ways to starve cancer cells of the nutrients they need to grow and to enhance the effectiveness of cancer treatments. The study, led by postdoctoral fellow Rebecca Delconte, PhD, demonstrated that fasting can reprogram the metabolism of natural killer cells, enabling them to survive in harsh tumor environments and improve their ability to combat cancer.
The findings of the study provide valuable insights into how fasting may help the body defend against cancer by reducing fat and improving metabolism. Fasting was found to reprogram natural killer cells to better survive in the nutrient-deprived environment of tumors, making them more effective in fighting cancer. The study results also suggest that fasting could enhance immune responses and improve the efficacy of immunotherapy, although further research is needed to fully understand the mechanisms involved.
Natural killer cells, also known as NK cells, are a type of white blood cell that can target and eliminate abnormal or damaged cells, including cancer cells. Unlike T cells, which require prior exposure to an antigen to mount a specific immune response, NK cells can detect and destroy threats without prior contact. The presence of NK cells within tumors has been associated with better prognoses for cancer patients, highlighting the importance of understanding how these cells can be empowered to combat cancer more effectively.
In the study, mice with cancer were subjected to periods of fasting, which led to alterations in the metabolism and distribution of NK cells within their bodies. The fasting cycles prompted NK cells to utilize free fatty acids as an alternative fuel source in the absence of glucose, optimizing their anti-cancer response. Additionally, fasting caused NK cells to migrate to the bone marrow, where they were exposed to high levels of Interleukin-12, a key signaling protein that enhanced their production of Interferon-gamma, an anti-tumor cytokine.
While the study focused on mice, the researchers observed similar effects of fasting on NK cells in human blood samples from cancer patients, suggesting potential translational implications for cancer treatment in humans. The researchers anticipate that further exploration of fasting as a strategy to improve immune responses and make immunotherapy more effective could lead to the development of novel treatments for cancer patients. Clinical trials are already underway to assess the safety and efficacy of fasting in combination with standard cancer treatments, with future research aimed at identifying drugs that target the underlying mechanisms of fasting-induced immunomodulation.
Although promising, more clinical data is needed to fully understand the effects of fasting on cancer patients and to determine the optimal fasting approaches for individual situations. Patients are advised to consult with their healthcare providers to determine the safety and appropriateness of incorporating fasting into their cancer treatment plans. The potential of fasting to enhance the anti-cancer properties of natural killer cells presents exciting opportunities for the development of innovative strategies to improve cancer treatments and outcomes.