As per new study patients with cervical cancer who make antibodies to sugars coatings appear to do better when they also receive internal radiation therapy.
National Institutes of Health and the Georgia Research Alliance supported the research.
The study was done on 578 Peruvian women with stage 2 and 3 disease.
It was conducted before treatment began and found those who ultimately fared best had naturally higher levels of antibodies that target 6 classes of sugars, or glycans, associated with cervical cancer.
The treatment of those who did best included a form of internal radiation called brachytherapy, known to rev up the immune response.
“All our cells are sugar coated and so are cancer cells, which use glycans for a variety of fundamental functions like cell proliferation, disease spread, and immune protection,” says Dr. Jin-Xiong She, director of the Center for Biotechnology and Genomic Medicine at the Medical College of Georgia at Augusta University.
The fact that these antibodies can neutralize glycans on cancer cells so they can’t be used may be the primary reason they are beneficial to cancer patients, says She, Georgia Research Alliance Eminent Scholar in Genomic Medicine and corresponding author of the study in the journal Gynecologic Oncology.
High levels of antibodies likely also indicate a generally high level of immune competency so patients can better fight the cancer, say She and first author Dr. Sharad Purohit, MCG biochemist. “It’s an indirect marker of antitumor immunity,” She says.
Pap smears, which look for precancerous cervical changes, have largely resulted in the significant decrease in the number of cases of cervical cancer and related deaths in the U.S. over the last 40 years, according to the Centers for Disease Control and Prevention.
But in less-developed countries like Peru, where screening, prevention vaccines and treatment are less available, about half of women have at least stage 2 cancer at diagnosis, which likely calls for a combination of surgery, external and internal radiation and chemotherapy. Still less than half of patients have access to those therapies, the scientists write.
Brachytherapy, in which radioactive material in the form of seeds, ribbons or capsules, is placed near or inside a tumor, is used in a variety of cancers in conjunction with and independent of external beam radiation, and is generally considered to have less side effects than external radiation. Most of the patients they studied received both internal and external radiation.
“Brachytherapy is a good treatment but it works better in patients who have antibodies,” says She. His and his colleagues’ long-term goals include helping all patients mount this natural, frontline immune response to cervical and other cancers.
The scientists looked at blood levels of anti-glycan antibodies in 276 patients with stage 2 and 292 patients with stage 3 cervical cancer treated at the Instituto Nacional de Enfermedades Neoplasiacas in Lima, Peru.
They screened for 177 glycans and ultimately found 13 anti-glycan antibodies against 6 classes of glycans associated with significantly better survival, and that the antibodies made a bigger impact on survival in patients with the more advanced stage 3 cervical cancer.
The system uses a patient’s blood or serum to find which sugars a patient is making antibodies to. She and his colleagues expect that broad-range glycan analysis may one day be part of an annual exam like a cholesterol level check.
Glycan antibodies are already used to determine good matches for blood transfusions and organ transplants.
Normally sugar coating helps cells know which other cells to bind to and helps them stick together, helps ensure cell contents stay inside, even provides protection from invaders like viruses and bacteria.
Cancer may also use glycans for protection, sending them out to help suppress the immune response and to essentially fertilize the tumor microenvironment by doing things like increasing signaling that promotes the growth of blood vessels and other essentials the tumor needs.