Past research has suggested that sulforaphane - a compound present in broccoli and other cruciferous vegetables - can help to prevent cancer or slow its progression. A new study may have discovered how.
Researchers from Oregon State University (OSU) found that sulforaphane reduced the expression of long noncoding RNAs (lncRNAs) in prostate cancer cells, which disrupted the cells' ability to form colonies - a hallmark of metastatic cancer.
Previously believed to be "junk DNA" with no significant function, lncRNAs have increasingly emerged as key players in the development of numerous cancers, including prostate, breast, stomach, and lung cancers.
Studies have suggested that lncRNAs can regulate gene expression - the process by which genes are switched on or off in order to do their jobs. When lncRNAs become dysregulated, it is believed that they can fuel disease development.
Not only does the new study provide further evidence of the role lncRNAs play in cancer, but it supports previous research hailing the anticancer effects of sulforaphane.
"It's obviously of interest that this dietary compound, found at some of its highest levels in broccoli, can affect lncRNAs," says principal study investigator Emily Ho, of the Moore Family Center for Whole Grain Foods, Nutrition and Preventive Health at OSU.
"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," she adds.
Ho and colleagues recently reported their results in The Journal of Nutritional Biochemistry.
Sulforaphane led to a fourfold reduction in colony formation
To reach their findings, the researchers conducted whole-genome sequencing on normal human epithelial prostate cells and prostate cancer cells.
They found that the prostate cancer cells showed high expression of lncRNAs, particularly one called LINC01116.
However, when the team administered sulforaphane to the prostate cancer cells, LINC01116 levels were reduced, leading to a fourfold reduction in the cells' ability to form colonies.
According to the researchers, their findings support the idea of IncRNAs as a target for cancer prevention, and they suggest that dietary intake of sulforaphane may be a feasible way to target these molecules.
Lead study author Laura Beaver, of the Linus Pauling Institute and College of Public Health and Human Sciences at OSU, says that their results may not only have implications for cancer prevention, but for cancer treatment.
"It would be of significant value if we could develop methods to greatly slow the progress of cancer, [and] help keep it from becoming invasive," she notes.
While further studies are needed to better understand how sulforaphane might prevent and slow cancer, the researchers believe that their findings help to shed some light.
The authors conclude:
"These discoveries illustrate that lncRNAs can play important roles in cancer development and may be useful targets for cancer prevention, detection, and treatment."