Epigenetic Biomarker Explains Racial Disparities in Patients with MM

Distinctive epigenetic pathways were discovered in African American and European American patients with multiple myeloma (MM), according to a Northwestern Medicine study published in the Journal of Hematology and Oncology.

The study carried out by Wei Zhang, Ph.D., and colleagues at Northwestern Medicine examined the contribution of 5-hydroxymethylcytosines (5hmC), a known epigenetic biomarker of cancers, to racial disparities in MM.

The researchers used 5hmC-Seal and next-generation sequencing to profile genome-wide 5hmC in circulating cell-free DNA (cfDNA) from 342 newly diagnosed patients with MMs. Two hundred and twenty-seven of these patients were European Americans, while one hundred and seventeen were African Americans. They also compared differential 5hmC modifications between MM and its precursors.

Although the diagnosis of MM is rare, previous studies have found that African Americans are two to three times more likely than European Americans to be diagnosed.

While risk variables such as socioeconomic status and obesity may contribute to the varied diagnosis rates in this patient population, they do not entirely explain the elevated risk in African Americans, according to Zhang.

The researchers identified about five hundred genes with different 5hmC levels; of these top five hundred genes, about ninety-five percent were distinct between European Americans and African Americans. Specifically, they discovered that African American patients had more amino acid metabolism pathways, whereas European American patients had more cancer-related signaling pathways.

According to the researchers, these findings helped them better understand the epigenetic contribution to racial disparities in MM and suggest epigenetic pathways that could be exploited as novel preventive strategies in high-risk populations.

“If we observe that population-specific 5hmC is related to differential patient survival, then we could actually utilize 5hmC as a novel biomarker that can help us monitor treatment response and detect patients with minimal residual disease in a population-specific way,” said Zhang.

 

Journal source: BMC

Source: Northwestern.edu