Chemicals found in the American food supply could play a role in the prognosis of prostate cancer, suggests a peer-reviewed article published in the International Journal of Molecular Sciences by researchers from the FIU Robert Stempel College of Public Health & Social Work.
Prostate cancer is the second leading cause of cancer deaths in American men. In 2021, 248,530 new cases were reported — a nearly 30% increase from the previous year. Men 65 years and older are most likely to be diagnosed with the disease. However, compared with white men, Black men are at greater risk of developing it and are more than twice as likely to die from it. Studies have shown that risk factors like age, BMI, race/ethnicity, obesity, diet, socioeconomic status and access to health care can be attributed to the increased risk.
The FIU study applied a risk assessment approach to examine exposures to environmental phenols (e.g., BPA) and parabens in American men diagnosed with prostate cancer. The study revealed both chemicals, alone and in combination, as possible risk factors for the disease.
The study used a 2005-2015 comprehensive dataset from the National Health and Nutrition Survey (NHANES), which helps the Centers for Disease Control and Prevention (CDC) monitor the health and nutrition of the American public. Among the 4,592 male survey participants, 152 self-reported a prostate cancer diagnosis.
Researchers at FIU analyzed the urine sample data of the participants and discovered a significant association of higher levels of environmental phenols and parabens in the urine samples of the prostate cancer patients. In addition, they found that higher levels of environmental phenols and parabens were consistent with the severity of prostate cancer, particularly in participants 65 years and older.
“Through our analysis, we saw an association between these chemicals and the disease, but we also wanted to understand what the triggering mechanism for prostate cancer might be,” said Alok Deoraj, professor of environmental health sciences and the lead author of the study. “What are the significant genes which may be involved?”
The researchers turned to various bioinformatic databases to uncover which genes were influenced by exposures to environmental phenols and parabens.
Using databases like the Comparative Toxicogenomic Database, the Cancer Genome Atlas, Cytoscape and UALCAN, researchers found 81 genes that were triggered by exposures to environmental phenols and parabens. In addition, higher expression of a set of hub genes— BUB1B, TOP2A, UBE2C, RRM2, and CENPF— were determined in the aggressive stages of prostate cancer tissues, hinting at their potential role in the severity of the disease prognosis.
Dia Alwadi, first author of the study and an FIU doctoral student of environmental health sciences, recognizes that the study has its limitations, including the use of self-reported data and challenges with establishing food exposure as the primary route of chemical exposure. Furthermore, the researchers suggest more research is needed to validate their results.
“Moving forward, we will focus more on the molecular pathways to evaluate what regulatory or other environmental factors might play a role in prostate cancer prognosis with these chemicals,” said Deoraj. “This would be our next stage in the follow-up study, especially if we can get access to more human data from patient databases.”
The U.S. Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA) estimate more than 10,000 chemicals are added directly or indirectly to the American food supply chain. Many of these chemicals, like environmental phenols and parabens, are known to disrupt hormones and are suspected to play a role in the development of cancers and other chronic diseases.
According to Alwadi, both chemicals can be found in everyday foods consumed by Americans.
“Environmental phenols, particularly Bisphenol A (BPA), are found in plastics and can seep into the food supply through canned foods, water bottles, and food storage,” he said. “While parabens, for example, are broadly used in food and beverage processing, pharmaceutical products, and personal care products.”
Both are listed under the EPA’s Toxic Substances Control Act, which monitors the impacts of chemicals in human health and the environment.
“Chemicals have improved our quality of life and have helped with the shelf life of food and medicine,” said Deoraj. “But the challenge we have is that we don’t have the toxicity profiles of the majority of those chemicals that we are exposed to on a daily basis. So, as public health professionals, we need to understand the toxic profiles of everyday chemicals so that we can help create prevention plans for the mitigation of their exposures to humans and their presence in our environment.”