Researchers have discovered a potential cancer link to allergies, that could lead to therapies based around antihistamines. Its been discovered that histamine may protect tumours from the immune system. By blocking the production of histamine in animal models, the researchers were able to interrupt a process that promotes skin cancer growth.
“This research is very exciting as it draws a connection between two diseases that aren’t commonly linked: allergy and cancer,” says Conrad. “However, it’s important to realize that this connection is very novel and further research is needed before we know if antihistamines can be used effectively in cancer therapies.”
Histamine is produced by mast cells, which are especially numerous in the nose, mouth and blood vessels to help defend against pathogens and aid in wound healing. The researchers found that histamine induces the activation, survival and proliferation of myeloid derived suppressor cells (MDSCs), which help promote tumorgrowth by suppressing the immune system. They also discovered that MDSCs tend to migrate toward mast cells, which help traffic the MDSCs to sites of inflammation such as the liver and tumors. The cycle continues as histamine released by mast cells further promotes the survival and proliferation of MDSCs. This occurs in two subpopulations of MDSCs, but most dramatically in the monocytic subpopulation. Through their experiments, the researchers showed that monocytic MDSCs can be decreased by over-the-counter antihistamines such as cetirizine (Zyrtec) and cimetidine (Tagamet).
In addition, the researchers found that patients experiencing allergic symptoms have more MDSCs circulating in their bloodstream than non-allergic patients.
MDSCs have generated a great deal of interest in recent years because they limit the effects of the immune response against cancer,” says study collaborator Harry D. Bear, M.D., Ph.D., member of the Developmental Therapeutics research program at Massey, professor and chair of the Division of Surgical Oncology at the VCU School of Medicine and director of the Breast Health Center at VCU Health System. “Now that we have shown that antihistamines can interfere with the production of MDSCs, we are hopeful that we may be able to use them to restore the immune system’s ability to fight off tumors.”
This breakthrough discovery of the possible cancer link to allergies may bring in a new era of research in the fight against cancer. The traditional approach of ‘killing’ the cancer cells using poisonous chemicals and radiation has been far from successful in our opinion and this lateral approach of allowing the bodies immune system to fight the cancer offers more hope.