Washington: A dietary compound found in broccoli may help prevent prostate cancer by influencing a type of RNAs that likely play a critical role in triggering cells to become malignant and spread, a new study claims.
Researchers from Oregon State University in the US said the long, non-coding RNAs (lncRNAs) were once thought to be a type of “junk DNA” of no particular value or function.
Growing evidence shows that lncRNAs, which number in the thousands, have a major role in cell biology and development, often by controlling what genes are turned on, or “expressed” to carry out their genetic function.
Scientists now believe that when these lncRNAs are dysregulated they can contribute to multiple disease processes, including cancer.
Unlike many chemotherapeutic drugs that affect healthy cells as well as malignant ones and can cause undesired side effects, the control of lncRNAs may offer a new way to specifically prevent or slow the progression of malignant cells.
“This could be a turning point in our understanding of how cancer may be triggered and spreads,” said Emily Ho, director of the Moore Family Centre for Whole Grain Foods, Nutrition and Preventive Health at OSU.
“It is obviously of interest that this dietary compound, found at some of its highest levels in broccoli, can affect lncRNAs. This could open the door to a whole range of new dietary strategies, foods or drugs that might play a role in cancer suppression or therapeutic control,” said Ho.
This research showed that one lncRNA, called LINC01116, is upregulated in a human cell line of prostate cancer, but can be decreased by treatment with sulforaphane.
The data “reinforce the idea that lncRNAs are an exciting new avenue for chemoprevention research, and chemicals derived from diet can alter their expression,” scientists said.
“We showed that treatment with sulforaphane could normalise the levels of this lncRNA,” said Laura Beaver, lead author on the study published in the Journal of Nutritional Biochemistry.
“This may relate to more than just cancer prevention. It would be of significant value if we could develop methods to greatly slow the progress of cancer, help keep it from becoming invasive,” said Beaver.
The impact of diet on lncRNA expression has been largely unknown until now, the researchers said. In this study, they identified a four-fold decrease in the ability of prostate cancer cells to
form colonies when LINC01116 was disrupted.
Among men, prostate cancer is the second most frequently diagnosed cancer globally, researchers said.
An increased consumption of cruciferous vegetables such as broccoli, which are high in sulforaphane, appears to be associated with a lower risk of developing prostate cancer.
That same lncRNA, they noted, is also overexpressed in studies of several other types of cancer, including brain, lung and colon cancer.