Next-gen cancer treatments could be only 5 to 10 years away

The next generation of light-activated cancer treatments sounds years away, but in what can be called a breakthrough, scientists at the University of East Anglia got several steps closer.

How will it work? When LED lights embedded near a tumor are switched on, it activates biotherapeutic drugs. These are highly targeted and would be more effective and precise than current immunotherapies.

Antibody fragments can form a covalent bond with their target

"Current cancer treatments like chemotherapy kill cancer cells, but they can also damage healthy cells in your body such as blood and skin cells," Dr. Amit Sachdeva, from UEA's School of Chemistry, who is the principal scientist for the study, said in a statement.

"This means that they can cause side effects including hair loss, feeling tired and sick, and they also put patients at increased risk of picking up infections. There has therefore been a very big drive to create new treatments that are more targeted and don't have these unwanted side effects."

Now, antibodies and antibody fragments have already been developed to treat cancer. The UEA team has engineered "one of the first antibody fragments that bind to and forms a covalent bond with its target - upon irradiation with UV light of a specific wavelength," as per the release.

Which translates into - drug molecules that could be permanently fixed to a tumor.

The treatment would work well for skin cancers and those with a solid tumor

"In other words, you could activate antibodies to attack tumor cells by shining light – either directly onto the skin, in the case of skin cancer, or using small LED lights that could be implanted at the site of a tumor inside the body. This would allow cancer treatment to be more efficient and targeted because it means that only molecules in the vicinity of the tumor would be activated, and it wouldn't affect other cells," Sachdeva explained.

Sachdeva stressed that the treatment would work for cancers like that of the skin or where there is a solid tumor but not for blood cancers like leukemia. 

If the next stage of research goes well, the 'next generation' light-activated immunotherapies could treat cancer patients within five to ten years. 

The study is published in the journal Nature Chemical Biology.

Study Abstract:

Design of biomolecules that perform two or more distinct functions in response to light remains challenging. Here, we have introduced concurrent photoactivity and photoreactivity into an epidermal growth factor receptor (EGFR)-targeting antibody fragment, 7D12. This was achieved by site-specific incorporation of photocaged tyrosine (pcY) for photoactivity and p-benzoyl-ʟ-phenylalanine (Bpa) for photoreactivity into 7D12. We identified a position for installing Bpa in 7D12 that has minimal effect on 7D12–EGFR binding affinity in the absence of light. Upon exposure to 365-nm light, this Bpa-containing 7D12 mutant forms a covalent bond with EGFR in an antigen-specific manner. We then developed a method for site-specific incorporation of pcY and Bpa at two distinct sites in 7D12. Finally, we demonstrated that in the absence of light, this pcY- and Bpa-containing mutant of 7D12 does not bind to EGFR, but irradiation with 365-nm light activates (1) specific binding and (2) covalent bond formation with EGFR.