Dana Farber. US: A new study by Dana-Farber Cancer Institute investigators demonstrates that vitamin D can protect some people with colorectal cancer by perking up the immune system’s vigilance against tumor cells.
The research, published today by the journal Gut,
represents the first time that a link between vitamin D and the immune
response to cancer has been shown in a large human population. The
finding adds to a growing body of research showing that vitamin D –
known as the “sunshine vitamin” because it is produced by the body in
response to sunlight exposure – plays a key role in cancer prevention.
“People
with high levels of vitamin D in their bloodstream have a lower overall
risk of developing colorectal cancer,” said the study’s senior author, Shuji Ogino, MD, PhD, MS,
of Dana-Farber, Harvard School of Public Health, and Brigham and
Women’s Hospital. “Laboratory research suggests that vitamin D boosts
immune system function by activating T cells that recognize and attack
cancer cells. In this study, we wanted to determine if these two
phenomena are related: Does vitamin D’s role in the immune system
account for the lower rates of colorectal cancer in people with high
circulating levels of the vitamin?”
Ogino and his colleagues
theorized that if the two phenomena were connected, then people with
high levels of vitamin D would be less likely to develop colorectal
tumors that are permeated with large numbers of immune system cells.
Colorectal tumors that do develop in these individuals would, by the same logic, be more resistant to the immune response.
To
determine if this is indeed the case, the research team drew on data
from 170,000 participants in the Nurses’ Health Study and Health
Professionals Follow-up Study, two long-term health-tracking research
projects. Within this population, researchers compared carefully
selected groups of 318 colorectal cancer patients and 624 individuals
who were free of cancer. All 942 of them had blood samples drawn in the
1990s, before any developed cancer. The investigators tested these
samples for 25-hydroxyvitamin D, (abbreviated 25(OH)D), a substance
produced in the liver from vitamin D.
They found that patients
with high amounts of 25(OH)D indeed had a lower-than-average risk of
developing colorectal tumors that were enriched with immune system
cells.
“This is the first study to show evidence of the effect of
vitamin D on anti-cancer immune function in actual patients, and
vindicates basic laboratory discoveries that vitamin D can interact with
the immune system to raise the body’s defenses against cancer,” Ogino
said. “In the future, we may be able to predict how increasing an
individual’s vitamin D intake and immune function can reduce his or her
risk of colorectal cancer.”
Funding for the study was provided by
the National Institutes of Health, the Friends of Dana-Farber Cancer
Institute, the Bennett Family Fund, the Entertainment Industry
Foundation, and the Paula and Russell Agrusa Fund for Colorectal Cancer
Research.
The co-lead authors of the study are Mingyang Song, MS,
of the Harvard School of Public Health, Reiko Nishihara, PhD, of
Dana-Farber and Harvard School of Public Health, Molin Wang, PhD, of
Harvard School of Public Health, and Andrew Chan, MD, MPH, of
Massachusetts General Hospital and Brigham and Women’s Hospital. The
co-senior authors with Ogino are Charles Fuchs, MD, MPH,
of Dana-Farber and Brigham and Women’s Hospital, Edward Giovannucci,
MD, ScD, of Harvard School of Public Health and Brigham and Women’s
Hospital; and Kana Wu, MD, PhD, of Harvard School of Public Health.
Co-authors are Zhi Rong Qian, MD, PhD, Kimmie Ng, MD, MPH,
Sun A. Kim, MD, PhD, Kosuke Mima, MD, PhD, and Yasutaka Sukawa, MD,
PhD, of Dana-Farber; Kentaro Inamura, MD, PhD, of Dana-Farber and the
National Cancer Institute; Xuehong Zhang, MD, ScD, of Brigham and
Women’s Hospital; and Katsuhiko Nosho, MD, PhD, of Sapporo Medical
University School of Medicine, Sapporo, Japan.