Restricted blood flows release cancer growth, the study reveals

The restricted blood circulation accelerates tumor growth by aging the immune system. The results highlight the risks for patients with vascular diseases and potential new therapies.

A new study by Nyu Langone Health Reports which restricts blood flow can accelerate the aging of bone marrow, reducing the ability of the immune system to fight cancer.

Research, published on August 19 Jacc-Cardiooncologynoted that peripheral ischemia – restricted circulation in the arteries of the legs – used breast tumors in mice to grow twice the speed observed in mice with normal blood flow. These results are based on a survey in 2020 by the same team, which has shown that ischemia during a heart attack produced similar effects.

How ischemia develops

Ischemia develops when fatty substances, such as cholesterol, accumulate inside the walls of the artery. This accumulation triggers an inflammation and a formation of clots, which limits the delivery of blood rich in oxygen. When ischemia occurs in the legs, it results in a disease of the peripheral artery, a condition that affects millions of Americans and increases the probability of heart attack or stroke.

“Our study shows that the altered blood circulation leads to the growth of cancer, it doesn’t matter where it occurs in the body,” explains the corresponding author Kathryn J. Moore, PhD, the cardiology teacher of Jean and David Blechman in the Medicine department of Leon H. Charney Division of Cardiology, Nyu Grossman School of Medicine. “This link between diseases of the peripheral artery and the growth of breast cancer highlights the critical importance of treating metabolic and vascular risk factors in the context of a complete cancer treatment strategy.”

Investigators also discovered that the restricted circulation moves the balance of immune cell populations in a manner that weakens the body’s ability to fight against infections and cancer. These alterations closely resemble the changes in immune function which normally occur with aging.

Systemic bias of immune cells

To investigate how cardiovascular disease Influence the progression of cancer, the researchers have created a mouse model carrying breast tumors and induces temporary ischemia in a posterior limb. They then compared the tumor development between animals with limited traffic and those with normal blood flow.

The results extend to what is known about the immune system, which has evolved to defend itself against bacteria and invading viruses and, under healthy conditions, to recognize and destroy cancer cells. These defense mechanisms depend on stem cell reserves in the bone marrow which can be activated if necessary to generate populations of crucial white globules throughout life.

In typical circumstances, the immune system against infection or injury by increasing inflammation to eliminate harmful agents and later reducing it to protect healthy tissues. This balance is based on a mixture of immune cells which amplify or suppress inflammation. The researchers discovered that the limited blood flow disturbs this balance by reprogramming the stem cells of the bone marrow. The discrepancy promotes the production of “myeloid” immune cells (monocytes, macrophages, neutrophils), which weakens immune defenses, while reducing the generation of lymphocytes such as T cells which are vital for the assembly of strong anti-cancer responses.

The tumor environment moves to the abolition

The local environment in tumors has shown a similar discrepancy, accumulating more immune cells – including LY6CHI monocytes, T4 / 80 + MHCIILO macrophages of M2 type and regulatory T cells – which protect cancer from immune attack.

Other experiences have shown that these immune changes were durable. Ischemia not only changed the expression of hundreds of genes, deploying immune cells in a more tolerant state to cancer, but also reorganized the structure of chromatin – protein scaffolding which controls DNA access, which makes it more difficult for immune cells to activate the genes involved in the fight against cancer.

“Our results reveal a direct mechanism by which ischemia leads to the growth of cancer, reprogramming stem cells in a way that resembles aging and promotes immune tolerance,” explains the first author Alexandra Newman, PHD, a postdoctoral scholarship holder in Dr. Moore’s laboratory. “These results open the door to new strategies in the prevention and treatment of cancer, such as prior cancer screening for patients with peripheral arterial disease and using modulative therapies by inflammation to counter these effects.”

In the future, the research team hopes to help to design clinical studies that evaluate if existing therapies targeted by inflammation can counter post-ischemic changes stimulating tumor growth.

Reference: “Development of cancer in atherosclerotic cardiovascular diseases: Jacc: short form of short cardiooncology” by Jessie M. Dalman, Ba and Kathryn J. Moore, August 19, 2025, Cardio oncology.
DOI: 10.1016/J.JACCAO .2025.05.016

The study was supported by the American Heart Association Grants 915560, 25CDA1437452, 23Post1029885, 25Pre1373174 and 23Scefia1153739; as well as by National Health Institutes subsidies T32GM136542, F30HL167568, T32HL098129; R01 HL151078, R01 HL161185, R35 HL161185, R01HL153712, R01HL172335, R01HL172365 and P01HL131481. The work was also supported by the SARNOFF CARDIOVASCULAR RESEACHE FOUNDATION, LEDUCQ Foundation Network, and Laura and Isaac Perlmutter Cancer Center Grant P30CA016087.

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