Helicobacter Pylori and Colorectal Cancer Risk Among Diverse Populations
Posted: Monday, November 19, 2018
Specific strains of the bacteria Helicobacter pylori were found to be associated with increased odds of developing colorectal cancer, with the strength of association varying between different races/ethnicities. These results are based on a study published in Gastroenterology by Meira Epplein, PhD, of the Cancer Control and Population Sciences Program, Duke Cancer Institute, Durham, North Carolina, and colleagues.
H pylori samples from 4,063 incident cases of colorectal cancer and 4,063 matched controls were analyzed using multiplex serologic assays. The majority of the study participants were white (75%), with 10% African American, 8% Asian, and 5% Latino. For both control and colorectal cancer groups, 4 in 10 cases were H pylori seropositive. General H pylori seropositivity varied substantially by race/ethnicity, being lowest in whites and Asian Americans and higher in African Americans and Latinos.
Seropositivity to four individual H pylori proteins—VacA, GroEL, Omp, and HcpC—were significantly associated with 10% to 11% increased odds of colorectal cancer in the total consortium but differed between races/ethnicities. Specifically, strong antibody responses to H pylori virulence factor VacA were significantly associated with odds of colorectal cancer, with those in the highest quartile of antibody response having a 25% higher change of colorectal cancer development.
“It was surprising to find VacA antibodies increased the odds of colorectal cancer in African Americans and Asian Americans, and not in whites and Latinos,” Dr. Epplein said in a Duke Health press release. “This is a big question: Are people harboring different bacteria based on genetic origin or heritage? This is part of what we need to figure out.”