Using CD47's protection to deliver anti-cancer drugs directly to tumor cells

October 9, 2012 by Marcia Goodrich
Ching-An Peng with students in his lab. Peng is studying new ways to get chemotherapy drugs to the site of a tumor.

(Medical Xpress)—For most of their natural lives, red blood cells hide safely under the radar of the body's immune system, thanks to a cloak of "don't eat me" protein called CD47. Ching-An Peng of Michigan Technological University wants to co-opt that clever trick to fight cancer.

Voracious called macrophages normally protect organisms by engulfing cell debris and pathogens. However, if they encounter something covered with CD47, such as a red blood cell, they tend to leave it alone. "I thought, 'Why not use CD47 to help deliver drugs?" said Peng. "We could camouflage them and avoid the immune response."

Nanoparticles hold great promise for delivering anti- directly to the site of a tumor. Getting them there, however, has been problematic, since macrophages stand at the ready to scoop the particles out of the blood stream before they can get to the the tumor and drop their cargo. Peng theorizes that if drug-bearing nanoparticles were coated with CD47, they could make it to the tumor unmolested.

CD47 also brings another weapon to the war against cancer. It binds to a special kind of protein found on tumors called an integrin. This integrin is involved with the network of that form around the tumor, blood vessels that provide the cancer with nutrients to fuel its out-of-control growth.

Thus, properly designed CD47-coated nanoparticles might deliver a one-two punch to cancer by 1) delivering and 2) choking off its food supply.

Research by Peng and his colleagues is in its early stages. They are using E. coli bacteria to mass produce CD47 in the lab using recombinant DNA technology. The next step will be to attach it to nanoparticles and expose them to macrophages, to see if the macrophages eat them up or—hopefully—ignore them.

Explore further: Research: Single antibody shrinks variety of human tumors transplanted into mice

Related Stories

Research: Single antibody shrinks variety of human tumors transplanted into mice

March 26, 2012
Human tumors transplanted into laboratory mice disappeared or shrank when scientists treated the animals with a single antibody, according to a new study from the Stanford University School of Medicine. The antibody works ...

Recommended for you

Vitamin C may encourage blood cancer stem cells to die

August 17, 2017
Vitamin C may "tell" faulty stem cells in the bone marrow to mature and die normally, instead of multiplying to cause blood cancers. This is the finding of a study led by researchers from Perlmutter Cancer Center at NYU Langone ...

Outdoor light at night linked with increased breast cancer risk in women

August 17, 2017
Women who live in areas with higher levels of outdoor light at night may be at higher risk for breast cancer than those living in areas with lower levels, according to a large long-term study from Harvard T.H. Chan School ...

Scientists develop novel immunotherapy technology for prostate cancer

August 17, 2017
A study led by scientists at The Wistar Institute describes a novel immunotherapeutic strategy for the treatment of cancer based on the use of synthetic DNA to directly encode protective antibodies against a cancer specific ...

Toxic formaldehyde is produced inside our own cells, scientists discover

August 16, 2017
New research has revealed that some of the toxin formaldehyde in our bodies does not come from our environment - it is a by-product of an essential reaction inside our own cells. This could provide new targets for developing ...

Cell cycle-blocking drugs can shrink tumors by enlisting immune system in attack on cancer

August 16, 2017
In the brief time that drugs known as CDK4/6 inhibitors have been approved for the treatment of metastatic breast cancer, doctors have made a startling observation: in certain patients, the drugs—designed to halt cancer ...

Researchers find 'switch' that turns on immune cells' tumor-killing ability

August 16, 2017
Molecular biologists led by Leonid Pobezinsky and his wife and research collaborator Elena Pobezinskaya at the University of Massachusetts Amherst have published results that for the first time show how a microRNA molecule ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.