TOKYO -- Hyaluronic acid, a gooey substance widely used in cosmetic procedures and in skincare products, is effective at both encouraging and suppressing cancerous tumor growth, according to a study by a University of Tokyo team.
The findings, published in American science journal Developmental Cell on May 10, show that when the molecules of hyaluronic acid have a greater mass, they act as an ally to the body in controlling the growth of cancer cells. However, in instances such as when cells are inflamed, its molecules break down, and it becomes an adversary to the body, encouraging tumor growth. The head of the report's team, Masanori Hatakeyama, a professor of molecular oncology, said the findings are a warning, "Simply putting the substance into our bodies always carries risks."
Hyaluronic acid naturally occurs in our skin and joints, helping to protect cells and maintain moisture levels. In beauty care, it is injected below the skin in procedures to enlarge the breasts and reduce wrinkles.
When inside the body, the molecules in hyaluronic acid typically form a long, chain-like structure. This changes when an area is under stress including inflammation. In such cases, an excessive amount of degrading enzymes is created, breaking down the chain into smaller molecules.
The team's attention was in researching what abilities cells have to block the development of cancers. Based on results from analysis of cells in a human mammary gland, they found that larger hyaluronic acid activated cancer suppression in cells. Conversely, smaller molecules limited cancer suppression, allowing it to grow more quickly.
Furthermore, in the cells of faster growing high-grade cancers, an excessive amount of degrading enzymes are created, so that even if larger hyaluronic acid molecules are introduced to the body, they are broken down and only exacerbate the cancer's progress.
Professor Hatakeyama said, "There's no guarantee that tissue injected with hyaluronic acid won't become inflamed. Even if you introduce larger molecules, as long as they are broken down in the body, then the risk of cancer is increased."
The team added that lotions and other products applied to the skin containing the substance are not considered dangerous. The chances of it being absorbed into the body from its surface are very low.
(Japanese original by Yuka Saito, Science & Environment News Department)