Cancer research has entered an era of rapid innovation, with scientists unveiling promising new therapies and uncovering surprising benefits of lifestyle interventions for survivors. On October 8, 2025, two major studies from leading institutions—MIT and Harvard Medical School, and the University of British Columbia (UBC) Okanagan—shed light on breakthroughs that could reshape the future of cancer treatment and survivorship.
For years, immunotherapy has stood at the forefront of the fight against cancer, with treatments like CAR-T cells revolutionizing care for blood cancers such as lymphoma and leukemia. But as reported by MIT and Harvard Medical School researchers in Nature Communications, a new weapon is emerging: engineered CAR-NK (chimeric antigen receptor-natural killer) cells. These immune cells, when reprogrammed, can hunt down and destroy cancer cells with remarkable precision. Yet, a persistent challenge has dogged their use—rejection by the patient’s own immune system.
Traditional approaches to creating CAR-NK or CAR-T cells require extracting a patient’s blood, isolating NK cells, and genetically engineering them to express a CAR protein that targets cancer. This process, which can take weeks, is not only time-consuming but also limits the viability of the resulting cells. As a workaround, scientists have explored using NK cells from healthy donors. However, these donor cells are often attacked by the recipient’s immune system before they can do their job.
The MIT and Harvard team, led by Professor Jianzhu Chen and Dr. Rizwan Romee, tackled this problem head-on. According to MIT, their innovation involves a one-step engineering process that makes donor CAR-NK cells nearly invisible to the host immune system. By using siRNA to suppress the expression of HLA class 1 proteins—surface markers that usually alert T cells to foreign invaders—and incorporating genes for the CAR, along with either PD-L1 or single-chain HLA-E (SCE), all on a single DNA construct, the researchers created CAR-NK cells that not only avoid immune rejection but also kill cancer cells more effectively and safely.
“This enables us to do one-step engineering of CAR-NK cells that can avoid rejection by host T cells and other immune cells. And, they kill cancer cells better and they’re safer,” said Professor Chen, as quoted by MIT.
To test their approach, the team engineered CAR-NK cells to target CD-19, a protein commonly found on cancerous B cells in lymphoma. In preclinical trials using mice with humanized immune systems, these modified CAR-NK cells maintained their population for at least three weeks and nearly eliminated cancer. In contrast, mice receiving either unmodified NK cells or those with only the CAR gene saw their donor NK cells wiped out within two weeks, allowing cancer to spread unchecked.
One of the most notable findings was the safety profile of these engineered cells. The study found that they were much less likely to trigger cytokine release syndrome, a dangerous and sometimes life-threatening complication of immunotherapy. “Because of CAR-NK cells’ potentially better safety profile, Chen anticipates that they could eventually be used in place of CAR-T cells,” MIT reported.
The implications are significant. If these results translate to humans, doctors could one day have access to “off-the-shelf” CAR-NK cell therapies—ready-made treatments that can be administered as soon as a diagnosis is made. This would be a dramatic shift from the current model, where patients must wait weeks for personalized cell engineering.
The research team is now preparing for clinical trials in collaboration with Dana-Farber Cancer Institute and is also exploring the use of CAR-NK cells for autoimmune diseases such as lupus. Funding for the study came from organizations including Skyline Therapeutics, the Koch Institute Frontier Research Program, and the National Cancer Institute.
While cutting-edge therapies like CAR-NK cells offer hope for eradicating cancer, another study out of UBC Okanagan, published on the same day in Nutrition and Cancer, highlights the ongoing challenges faced by survivors—particularly women recovering from breast cancer. Dr. Sarah Purcell and her team investigated how exercise might help breast cancer survivors manage a common and troubling side effect of treatment: weight gain.
Breast cancer survivors, especially those undergoing long-term estrogen-blocking endocrine therapy, often experience weight gain, which in turn raises the risk of obesity, heart disease, diabetes, and even cancer recurrence. “Breast cancer survivors generally have favourable overall survival rates,” Dr. Purcell explained to UBC. “However, many have an elevated risk of weight gain, which can lead to obesity and eventual further complications such as heart disease and diabetes.”
The cause of this weight gain has remained elusive, but Dr. Purcell’s research offers a new clue. Her team studied female breast cancer survivors—most of whom were premenopausal before diagnosis and were currently receiving endocrine therapy—and compared them to adults with obesity or high body weights. The results were eye-opening.
After exercise, breast cancer survivors showed higher levels of the appetite-suppressing hormone Peptide YY (PYY) than women without a history of cancer. “Our study shows that exercise can do more than build strength for these survivors—it may also help control appetite,” Dr. Purcell said. The effect was unexpected, as estrogen-blocking therapies are typically associated with weight gain, not weight loss. Yet, the survivors’ hormone levels revealed a stronger appetite-suppressing response after physical activity, and they ate less relative to their body size.
“The breast cancer survivors had higher PYY levels right after exercise, which suggests their appetite-suppressing response lasted longer,” Dr. Purcell noted. “This unexpected result shows a novel interaction between exercise and estrogen suppression that has not been seen in healthy groups before.”
Although participants did not report feeling less hungry, their bodies responded differently, suggesting that exercise may help manage treatment-related weight changes by tapping into natural appetite-control systems. The findings underscore the importance of regular physical activity—not just for improving strength and cardiovascular health, but also as a tool for appetite regulation and weight management during and after cancer treatment.
Both studies, published on October 8, 2025, point to a future where cancer care is increasingly personalized, blending high-tech immunotherapies with lifestyle interventions tailored to survivors’ unique needs. As researchers push forward with clinical trials and further investigations, patients and clinicians alike have new reasons to hope—and new tools to fight back against cancer and its lingering effects.
These advances, from the lab bench to the yoga mat, are reshaping what it means to survive and thrive after cancer.
