Triple-negative breast cancer has low survival rates. There are no targeted therapeutics for this deadly breast cancer so far, because it doesn't have
any of the receptors on it that are normally targeted.
Targeted cancer therapies rely on specific markers on the surface of
cancer cells. Scientists can design antibodies that seek out those
markers and deliver therapeutic or imaging agents. However, some cancers
are not eligible for this kind of treatment because they lack surface
markers to target.
‘A way to tag and target elusive cancers with small-molecule sugars has been discovered. This opens treatment pathways for cancers that are not responsive to conventional targeted antibodies, such as triple-negative breast cancer.’
By hijacking a cancer cell's own metabolism, researchers have found a
way to tag and target elusive cancers with small-molecule sugars. This
opens treatment pathways for cancers that are not responsive to
conventional targeted antibodies, such as triple-negative breast cancer.
Led by Jianjun Cheng, a Hans Thurnauer Professor of Materials
Science and Engineering at the University of Illinois, researchers at
Illinois and collaborators in China published their findings in the
journal Nature Chemical Biology
The researchers found a way to mark the cells using a class of
small-molecule sugars called azides. Once metabolized in the cell, they
are expressed on the surface, and can be targeted by a molecule called
"It's very much like a key in a lock. They are very specific to each
other. DBCO and azide react with each other with high specificity. We
call it click chemistry," Cheng said. "The key question is, how do you
put azide just on the tumor?"
To make sure the azide would only be expressed on the surface of
cancer cells, the researchers added a protective group to the azide
sugar that could only be removed by tumor-specific enzymes. In normal
tissues, the azide sugar simply travels through. In tumor cells, it is
completely metabolized and expressed on the cell surface, creating
specific targets for DBCO to deliver a cargo of cancer-treating drugs or
The researchers tested the azide-based targeting system in mice with
tumors from colon cancer, triple-negative breast cancer and metastatic
"We found the tumors had very strong signals compared with other
tissues," Cheng said. "For the first time, we labeled and targeted
tumors with small molecule sugars in vivo, and we used the cancer cell's
own internal mechanisms to do it."