Cancer Treatments Under scrutiny as Research Uncovers Links to Heart Problems
Barcelona, Spain – Emerging research presented this week at the 2025 ESC Cardio-Oncology Annual Conference is shedding light on the mechanisms behind cardiovascular adverse events associated with several cancer therapies, prompting calls for increased cardiac monitoring of patients. Studies are focusing on both direct toxic effects and potential protective pathways, offering a more nuanced understanding of the risks and possibilities for mitigation.
One study highlighted notable cardiotoxic effects linked to the CDK4/6 inhibitor ribociclib, occurring through the CDK4/6-Rb-E2F1 pathway. researchers, led by Ms.Pet,presented findings suggesting a need for careful cardiac monitoring in patients receiving these agents (Pet E,2025 ESC Cardio-Oncology Annual Conference). This concern is supported by a recent meta-analysis published in the American journal of Cardiovascular Drugs which documented cardiovascular events associated with CDK4/6 inhibitors (Zhang C, et al., 2025).
However, not all findings point to increased risk. Dr. MB Heckmann’s research suggests a potential cardioprotective role for a dysfunctional GBP5 molecule, potentially reducing mortality from radiation-induced heart damage (heckmann MB, 2025 ESC Cardio-Oncology Annual Conference).
A third study, led by Dr. M Fleming, is investigating the link between ibrutinib, a BTK inhibitor used to treat blood cancers, and atrial fibrillation.The preclinical research revealed marked changes in mitochondrial structure following ibrutinib exposure, with a dose-dependent response observed in mean mitochondrial intensity (P* <.001 and *P < .0001 for ibrutinib at 1 and 10 μM, respectively). Principal component analysis further demonstrated significant differences (*P* < .0001) in mitochondrial structure between ibrutinib- and vehicle-treated atrial-specific cardiomyocytes.
“Ibrutinib exposure causes marked changes in multiple indices of mitochondrial structure, implicating altered mitochondrial function in the development of ibrutinib-related atrial fibrillation,” Dr. Fleming concluded. Importantly, Dr. Fleming also noted differences in the effects of ibrutinib versus acalabrutinib, another BTK inhibitor, suggesting potential variations in cardiac risk within the drug class (Fleming M, 2025 ESC Cardio-Oncology annual Conference).
the American Cancer Society reports a growing number of cancer survivors, highlighting the increasing importance of understanding and managing long-term side effects of treatment (American Cancer Society, https://www.cancer.org/research/cancer-facts-statistics/survivor-facts-figures.html, accessed July 3, 2025). These new findings underscore the need for continued research into cardio-oncology and the development of strategies to minimize cardiovascular risks for cancer patients.
Disclosures: Ms.Pet reported no conflicts of interest. Dr. Heckmann has received speaker honoraria from Bristol Myers Squibb and Daiichi Sankyo. Dr. Fleming has received research support from an american Heart Association Career Development Award and a Vanderbilt Clinical Oncology Research Center Career Development Program K12 Award.
