Study reveals that chemotherapy works in an unexpected way

It's generally thought that anticancer chemotherapies work like antibiotics do, by directly killing off what's harmful. But new research published online on April 4 in the Cell Press journal Immunity shows that effective chemotherapies actually work by mobilizing the body's own immune cells to fight cancer. Researchers found that chemo-treated dying tumors secrete a factor that attracts certain immune cells, which then ingest tumor proteins and present them on their surfaces as alert signals that an invader is present. This new understanding of how chemotherapy works with our immune systems could prompt new tactics for treating cancer.

"Successful chemotherapeutics convert the tumor into a , hence mobilizing the host's immune system against the cancer," explains senior author Dr. Guido Kroemer, of the Institut Gustave Roussy, in France.

Dr. Kroemer and his colleagues found that when chemotherapy kills and bursts open , the cells release a factor called ATP. The factor recruits to the tumor site, where they are educated to acquire their function—namely, to ingest and present tumor proteins on their surfaces. The researchers found that when these trained immune cells are blocked, chemotherapy (specifically, anthracyclines) cannot efficiently reduce the growth of tumors in mice. Also, when these trained immune cells are injected into other mice, the mice can fight off cancer cells that are subsequently injected.

The findings point to a new strategy to improve cancer treatments. "Anticancer therapies and immunotherapies might be combined in a way to optimize the local recruitment and function of immune cells—for instance, by increasing extracellular ATP levels—with the goal of boosting the chemotherapy-induced anticancer immune response," says Dr. Kroemer. Also, measuring the recruitment of immune cells to tumor sites after chemotherapy might help predict how well a patient's cancer will respond to the treatment.

More information: Immunity, Ma et al.: "Anticancer chemotherapy induced intratumoral recruitment and differentiation of antigen presenting cells." dx.doi.org/10.1016/j.immuni.2013.03.003

add to favorites email to friend print save as pdf

Related Stories

Immune-response genes affecting breast tumor eradication

May 03, 2012

Breast cancer patients whose tumors express high levels of genes related to immune response are more likely to have their tumor completely eradicated by pre-operative chemotherapy compared to patients with low expression ...

Mechanism for esophageal cancer uncovered

Apr 11, 2011

A gene thought to be associated with cancer development can be a tumor suppressor gene in mice, researchers have discovered. Understanding which genes are involved in spreading cancer could lead to future therapies.

Chemotherapy might help cancer vaccines work

May 16, 2008

Chemotherapy given in conjunction with cancer vaccines may boost the immune system’s response, potentially improving the effectiveness of this promising type of cancer therapy, according to a study by researchers in the ...

Tumor environment keeps tumor-fighting T cells away

Sep 19, 2011

Tumors have an arsenal of tricks to help them sidestep the immune system. A study published on September 19 in the Journal of Experimental Medicine reveals a new trick -- the ability to keep tumor-fighting T cells out by ...

Recommended for you

Invading worms cause the body to shut down defenses

6 hours ago

When parasitic worms invade muscle tissue, white blood cells called eosinophils rush to the scene. A study published in the Journal of Immunology this month reveals that these cells actually start a chai ...

Skin exposure may contribute to early risk for food allergies

Oct 08, 2014

Many children may become allergic to peanuts before they first eat them, and skin exposure may be contribute to early sensitization, according to a study in mice led by Mount Sinai researchers and published today in the Journal of ...

User comments