Laser-guided Cancer Drugs

Cancer treatment augmented by new photoimmunotherapy

(RxWiki News) One of the biggest problems with any medication is not knowing where it will end up in the body. With drugs designed to kill cells, such as chemotherapy, healthy cells are also killed - leading to unpleasant side effects.

That may be changing.

New research in an emerging field called photo-immunotherapy has successfully combined the latest anti-cancer drugs called monoclonal antibodies, with a molecule that activates when exposed to light.

Using this method, targeted radiation known as infrared light therapy can activate the chemotherapy in the region of the cancer alone, leaving the rest of the body unaffected. 

"Ask your oncologist about new treatments."

Hisataka Kobayashi, M.D. Ph.D., lead scientist of the Molecular Imaging Program, and his team from the National Cancer Institute successfully demonstrated the viability of the technique in studies on mice.

The molecule, made up of several components including the drug and light-activated dye, successfully attached to the cancer cells. When the cancer was exposed to a specific spectrum of light, the molecule went into action and the targeted cells died quickly, without harming nearby healthy cells.

In the study, researchers used a molecule called IR700 as the light-activated dye, attached to a monoclonal antibody.  Three different cancer markers were tested -  HER2, EGFR, and PSMA. The antibodies carry the drug to the cancer cells that have these markers, and sit there waiting to be activated by the special light. 

HER2 is seen in some forms of breast cancer. EGFR is frequently found in forms of lung, pancreatic and colon cancer, and PSMA is unique to prostate cancer.

Dr. Kobayashi states, “Although more testing will be needed, we believe this method has the potential to replace some surgical, radiation and chemotherapy treatments.”

Results from the study were published in the journal Nature Medicine in November 2011.

This research was funded by the National Cancer Institute.

Review Date: 
January 21, 2012