Cancer vaccine based on sugar on the way
Carcinomas, types of cancer which include prostate, lung, ovarian and breast cancer, among others, will be treatable and curable by a new vaccine which is based on molecules of sugar residing on the surface of cancer cells. Scientists from Moores Cancer Center at the University of California are set to develop a new kind of immunotherapy primarily for prostate cancer, but applicable for other types of cancer.
The leader of the research team, Alessandra Franco, MD, PhD, along with her co-workers spent the last 10 years proving that T-cells (“killer”) can recognize sugars on tumor cell surfaces. Her team pioneered and developed the notion that conventional T-cells recognize not only peptides, or pieces of proteins, but also sugars, specifically small carbohydrates called tumor-associated carbohydrate antigens (TACA) expressed on carcinoma cell surfaces. Ideally, this recognition enables the T-cell to attach to and kill the cancer cell.
The scientists have designed “glycopeptides,” compounds in which sugars are linked to peptides that are recognized by T-cells. When given as part of a vaccine therapy, these glycopeptides rouse immune system T-cells into recognizing TACA on tumor cell surfaces, attacking and killing the cancer cells.
There are numerous immunotherapies for cancer in this moment of time, but they are all focused on making antibodies recognize proteins on tumor cells.
“A limitation with current immunotherapies is that every tumor expresses different protein antigens, which all need to be characterized,” said Franco. “It is difficult for the immune system to discriminate, to tell that cancer cells are ‘non-self’ and should be destroyed. What’s nice about T-cells recognizing sugars and why it’s so important in cancer is because the same molecules are uniquely expressed in a large variety of cancers.”
The research is supposed to last two years. In the first year, the team plans to gather as much laboratory data as possible. In the second year, the clinical trials should begin.
“The beauty of this approach is that the same vaccine may prevent metastasis,” she said, noting that tumor cells can use sugar or carbohydrate antigens to spread. “If ultimately proven successful, this could be used in a first attempt to try to address vaccination on a large scale to prevent cancer.”
The whole project is funded by Gateway for Cancer Research from Illinois.
Source: cancer.ucsd.edu
