Written by: Rebecca Hoffa, rhoffa@purdue.edu
Colorectal cancer is the third most common cancer diagnosis in the United States, not including skin cancers, according to the American Cancer Society, and there are expected to be more than 150,000 new cases of colon or rectal cancer by the year 2024. Although there has been an increase on the number of people getting screened. decrease in the incidence of colorectal cancer overall, early onset colorectal cancer cases continue to climb.
Patricia Wolf, an assistant professor in Purdue University’s Department of Nutritional Science, is working to reduce this statistic, especially for marginalized and underserved communities. With a recent grant of $917,000 from the American Cancer Society, Wolf is investigating how the metabolism of cysteine, a protein in the diet, interacts with the gut microbiome, or the microorganisms in the human digestive tract, to influence the incidence of colorectal cancer.
![Patricia Wolf headshot](https://www.purdue.edu/hhs/news/wp-content/uploads/2024/03/BP5_7939-1.png)
Patricia MacTyre(Photo provided)
“I’m interested in cysteine metabolism because when microbes break it down, they create cysteine - hydrogen sulfide – and my previous work has shown that these microbes are abundant in the gut and may be associated with cancer,” said Wolf. “Our previous work, which first looked at differences in the gut microbiome between non-Hispanic whites and blacks, showed that some of these cysteine-metabolizing bacteria were associated with cancer in Black participants. I wanted to follow this up and start thinking about why these microbes might be more abundant and whether that is related to dietary intake.”
Based on her previous work, Wolf thinks that the foods available in communities play a role in the risk of colorectal cancer. She explained that individuals with limited access to whole foods who eat more processed foods are more likely to have increased amounts of cysteine.
“Cysteine is not only abundant in high-protein foods—it’s also a food additive,” Wolf said. “I’m thinking it might be an understudied area: How do food additives affect the gut microbiome?”
Pius Sarfo Buobu, a graduate student in the College of Health and Human Sciences, was drawn to Wolf’s research because of his clinical nutrition background and passion for population nutrition and translational research. He said he is excited to dive deeper into understanding the direct implications of diet in underserved communities and populations as part of Wolf’s research team.
“The food environment defines what you have available, what you have access to and the types of food you can choose from.” Buobu said. “What kind of grocery stores and restaurants do you have in your neighborhood? Is it dominated by fast food joints? It is likely that all these factors can influence the development of colorectal cancer. For example, if you have a lot of fast food joints, you could be eating a lot more processed foods and a high-fat diet, which has been linked to developing colorectal cancer. It’s not like the food is acting alone. It affects the microbiome of the gut, and the microbes there may influence the development of colorectal cancer.”
![Head shot by Pius Sarfo Buobu](https://www.purdue.edu/hhs/news/wp-content/uploads/2024/03/Doc1-1-e1709300326911.png)
Pius Sarfo Buobu(Photo provided)
Wolf was also awarded an AgSEED grant from the Purdue College of Agriculture, in which she hopes to further explore rural food environments and how they affect colorectal cancer risk, overcoming even some of the demographic disparities she investigated. in the past.
“There is very limited data on the gut microbiome in general in underserved communities,” Wolf said. “Targeting these communities will hopefully provide more data to the field in general that will push us to understand some of these mechanisms. I want to make sure that my work ultimately serves these communities.”
Wolf and Buobu noted that past research literature has shown that healthy diets are important for taking protective measures against the occurrence of colorectal cancer, especially diets rich in fiber sources, such as whole grains, fruits and vegetables.
“Based on what I’m interested in, the Mediterranean dietary pattern seems to have the right ratios of amino acids to protect against some of these risk factors, assuming that what the microbes are doing varies, ” said Wolf.
Wolf often looks to the future as her work continues to develop, and her goals are to change policy and the food industry to help lower colorectal cancer rates.
“I always see potential connections to how it might affect underserved communities, but I’m also curious about early-onset colorectal cancer, which is considered the leading cause of cancer in people under 50 years old by 2030, and part of it. our preliminary data show that these bacteria are associated with early-onset colorectal cancer,” said Wolf. “I hope we can continue with it and find ways we can use food to make a difference.”