African-Americans are substantially more likely to develop and die of gastrointestinal cancers than other populations, a disparity that has persisted for years, say Long Island scientists who are launching an ambitious investigation of the human genome to find out why.
"We are not looking at socioeconomic status," said Dr. Jennie Williams, a cancer geneticist at Stony Brook University School of Medicine, who is hypothesizing that the answers may be indelibly inscribed in the genome.
Williams said she and her collaborators will focus on colon and pancreatic cancers, two gastrointestinal cancers that more frequently strike and kill African-Americans.
While these malignancies are devastating for anyone who develops them, data from the American Cancer Society reveal that African-Americans die at notably higher rates. For example, the death rate for black men with colorectal cancer is nearly 30 per 100,000, compared with 19.5 per 100,000 for white men.
Black women have a 19.8 per 100,000 death rate, according to the society's data, compared with 13.6 for white women. Colorectal cancer is the third most common cause of cancer in the United States.
Pancreatic cancer, silent and lethal, has a higher incidence rate among black patients than among all populations, Stony Brook scientists say. However, only 7 percent survive five years after diagnosis regardless of ethnicity, experts say.
The Pancreatic Cancer Action Network, an advocacy group, reports a pancreatic cancer incidence rate among African-Americans that is 31 percent to 65 percent higher than other racial groups, but those numbers could not be confirmed Thursday.
Williams is working with a team of researchers at Stony Brook and with scientists at Cold Spring Harbor Laboratory and SUNY Downstate in Brooklyn. They will study genes associated with colon and pancreatic cancers. The initiative is funded by the National Cancer Institute and a SUNY Health Network of Excellence grant.
Yet as these medical investigators begin examining two devastating cancers, they have been stymied by a key obstacle. Scientists who study cancer often use tissue samples developed from cell lines of the population under study.
But Stony Brook scientists say they have been unable to locate colorectal cancer cell lines propagated from tumors of African-Americans, samples that are needed to effectively examine any unique genetic features associated with the cancer.
Private, public and nonprofit institutions that grow the cells for cancer research did not develop cell lines from African-Americans, despite the population being hit hardest by the cancer, Williams said.
Dr. Ellen Li, chief of gastroenterology and hepatology at Stony Brook, said the new research effort is expected to change the lack of colorectal cancer cell lines. "This is a very important study and my role is to make things happen so we can get it done," Li said.
Because of the multi-institutional collaboration, she said the team effort will likely "break this barrier by attaining tissue samples from relevant patient populations, from both Stony Brook and Downstate."
In effect, she said, the local research will provide the most robust cell lines of the cancer in U.S. history.
The cell-line issue is less problematic with pancreatic cancer, Williams said, because that arm of the research is part of an ongoing Cold Spring Harbor investigation led by Dr. David Tuveson, deputy director of the lab's cancer center.
Tuveson has examined so-called pancreatic organoids derived from healthy human pancreatic stem cells, which are biological blank slates capable of morphing into complex tissues under certain lab conditions.