Eating broccoli and other cruciferous vegetables can lower a man’s risk of developing prostate cancer, thanks to a phenotype linked to the highly enriched levels of sulforaphane in these vegetables.
Now, scientists at Oregon State University (OSU) suggest that sulforaphane exerts its effects by targeting damaging levels of long non-coding RNAs (lncRNAs). Their study, “Long noncoding RNAs and sulforaphane: a target for chemoprevention and suppression of prostate cancer,” appeared in The Journal of Nutritional Biochemistry.
The team analyzed the whole RNA content of normal human prostate epithelial cells and prostate cancer cells, both when treated with sulforaphane or with an innocuous substance, in this case dimethylsulfoxide. It found that sulforaphane changed the expression of about 100 lncRNAS and normalized the levels of some lncRNAs whose expression was altered in cancer cells.
“It’s obviously of interest that this dietary compound, found at some of its highest levels in broccoli, can affect lncRNAs,” Emily Ho, the study’s principal investigator, said in a press release. “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.”
Ho directs OSU’s Moore Family Center for Whole Grain Foods, Nutrition and Preventive Health, and is also a professor in the College of Public Health and Human Sciences.
The levels of one particular lncRNA. LINC01116 — whose expression is increased in several cancers — dropped after sulforaphane treatment.
“We showed that treatment with sulforaphane could normalize the levels of this lncRNA,” said Laura Beaver, the study’s lead author and a research associate in the Linus Pauling Institute and College of Public Health and Human Sciences. “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.”
Researchers showed that LINC01116 promotes prostate cancer, since decreasing LINC01116 expression decreased proliferation of cancer cells.
Even more importantly, they showed that eating more broccoli and other cruciferous vegetables lowered the risk of developing prostate cancer.
“Taken together, this literature and our own study begin to paint a picture of the important and previously unappreciated role of lncRNAs in the body’s response to diet,” researchers concluded. “These discoveries illustrate that lncRNAs can play important roles in cancer development and may be useful targets for cancer prevention, detection and treatment.”