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Cells to Society: New centers explore two major areas of cancer disparities

New cancer risk maps? These maps of 1990, 2000, and 2011 dramatically show the steady increase in obesity rates of U.S. adults, defined as a body mass index (BMI) of 30 or more, which translates to 174 pounds for a 5-feet-4-inch adult and 220 pounds for a six-foot adult. For the full effect, see the animated sequence of annual maps at http://www.cdc.gov/obesity/data/trends.html. Courtesy of the U.S. CDC.

The earlier onset, higher rates, and worse outcomes of cancer in poor and minority populations in the United States may be well documented, but they are not well understood. Members of the Cancer Risk and Disparities Program are looking "upstream" of cancer risk factors to identify and remedy the underlying reasons, such as why more Americans are becoming obese or are continuing to smoke tobacco.

To help lower the cancer risk, researchers are exploring the social context of risk factors. They are looking at risk determinants over a life course and across populations groups, and are designing and testing innovative interventions. They are also working to translate and disseminate the findings into sustainable community based solutions. The Program is led by Lindsay Frazier, MD, ScM (DFCI) along with co-leaders David R. Williams, MPH, PhD (HSPH), and K. “Vish” Viswanath, PhD (DFCI).

Two newly funded research centers led by DF/HCC members—the Lung Cancer Disparities Center and the Harvard Transdisciplinary Research on Energetics and Cancer (TREC) Center—showcase some of the depth and breadth of the Program research. The Centers have recently dispatched teams across a broad spectrum of disparities-related investigations that reflect the changing dynamics of a pair of major public health threats: smoking and obesity.

Research tactics in both centers range from molecules to media and from genes to geography. Ambitious and multi-faceted studies explore key biological and social underpinnings and test innovative interventions scaling up from drugs to individual behaviors to the community context. Both centers also place a high priority on training the next generation of investigators in these fields.

Lung Cancer Disparities Center: Pulling the levers of social change

Lung cancer remains the most deadly cancer for men and women in the United States. “We're attempting to look at multiple places along the continuum of lung cancer to think about prevention and intervention, what we can do to get people to quit smoking, and to understand the basic biology of lung cancer and the potential treatment implications," says Williams, the center director.

Last year, the Lung Cancer Disparities Center commenced five projects with a mandate to directly tackle the racial-ethnic and socioeconomic disparities that contribute to the leading cause of cancer deaths, as well as to its main risk factor, smoking.

“As a society, our rates of smoking have gone down, and we have to celebrate that success,” Williams says. “On the other hand, most of the decline in cigarette smoking and mortality has come from among the higher education and income groups. Smoking is becoming increasingly concentrated in the lower socioeconomic levels, including socially disadvantaged racial and ethnic populations.”

One project in the Lung Cancer Disparities Center aims to reduce health disparities in tobacco use and other risk factors by intervening at the level of public discourse and community structure. A major objective of Project IMPACT is to help reframe the causes and solutions for health disparities with a focus on social context, such as improving access to cessation treatment, promoting tobacco control policies and reducing disparities in treatment.

“Most behavioral interventions focus on the individual: quit smoking, exercise more and eat healthy," says Viswanath, project leader. “Our focus is on the public agenda and political will. I think that's where the solution lies.”

Viswanath's team will train people in several dozen community-based organizations to work with the news media to highlight an issue of health inequality, as well as the social and policy contexts in which these inequalities occur. They will also develop a tool kit for reporters and test the effects. (See sidebar.)

“After the intervention is over, we will have trained dozens of people who will be skilled at working with media to advance the cause of addressing health disparities,” he says. The project builds on a six-year partnership between DF/HCC and HSPH researchers and the Lawrence community established as part of MassConnect (Massachusetts Community Networks to Eliminate Cancer Disparities Through Education, Research, and Training).

The details of the media message will be shaped in large part by a public opinion survey now underway. Nine teams of high school science students and community college students in Lawrence, Mass., have been knocking on neighborhood doors to finish baseline interviews of 1,100 households before Thanksgiving. Among other things, the questions assess people's tobacco use and their assumptions about the reasons for smoking and for not quitting. 

“We're curious to know how people now think about health disparities and health inequalities,” Viswanath says. “One, do people think about it at all? Two, if they think about it, how do they explain it? As humans, we try to explain the unknowns.” 

For example, do people in the Lawrence community attribute the greater proportion of smoking in poor and minority populations to discipline, willpower, or even enjoyment of risky behavior? Or might they explain the health disparities in tobacco to stress about money, family and jobs, or blame it on nefariously targeted tobacco promotions and advertising?

In year five of the project, the team will take another survey and also analyze the local media content to see if there is more attention to health disparities and support for actions to build the community capacity for sustained change. Viswanath and his team hypothesize that the intervention may help Lawrence citizens and the media  pay greater attention to health disparities and to the social conditions that lead to disparities than to individual factors, such as lack of will power. If it works, the intervention is portable to interventions can be applied to other risk factors underlying health care disparities, he says.

Two other projects in the Lung Cancer Disparities Center examine the role of health care providers within the context of larger social, demographic, and geographic factors. To help people implement their doctor's advice to quit smoking, Jennifer Haas, MD, MSc (BWH), is testing automated calls based on electronic health records that feature voice-interactive responses and include referrals to a social worker able to help address additional barriers to quitting. Meanwhile, John Ayanian, MD, MPP (BWH) is digging into key clinical factors and the context of care, including places of care and of residence, that may be contributing to survival disparities in lung cancer.

In another major project in the Center, Matthew Meyerson, MD, PhD (DFCI) and his team are drilling down to look for gene mutation patterns in lung adenocarcinoma that may cluster around racial-ethnic or socioeconomic differences. At the neighborhood level, Jarvis Chen, ScD (HSPH) and Nancy Krieger, PhD (HSPH) will develop methods to improve routine monitoring of cancer survival by providing more accurate estimates of both racial and socioeconomic disparities in lung cancer survival.

TREC Center: Clarifying links between obesity and cancer

Unlike tobacco, obesity hasn't been a major blip on the radar screen of most cancer researchers for long. “Obesity has skyrocketed in the past few decades,” Hu says. “Epidemiology and basic science show strong links between obesity and cancer, especially colorectal cancer, postmenopausal breast cancer, and endometrial cancer. Converging evidence and the changing obesity landscape in the United States have led us to the realization that if we want to reduce the burden of cancer, we must deal with obesity as an important risk factor.”

In June, the Harvard TREC Center became one of four funded by the National Cancer Institute (NCI) to look at the effects of energy balance and obesity on cancer risk and prevention. And this summer, the NCI elevated the question, “How does obesity contribute to cancer risk?” to a final list of 24 “provocative questions”—unsolved, paradoxical or neglected research questions that deserve a closer look and designated funding.

Two months ago, the Harvard Transdisciplinary Research on Energetics and Cancer (TREC) Center launched four projects with an overarching goal to provide insights into the relationship between obesity and cancer to help improve survival of cancer and reduce obesity in patients and the general population. The TREC Center isn't specifically tasked with addressing health disparities, but obesity is one of the conditions with some of the highest health disparities, says center director Frank Hu, MD, PhD (HSPH).

“Obesity has more than doubled in the last 30 years," says Hu. The latest U.S. statistics count one-third of people as overweight and one third as obese. “Minorities, especially African Americans and Hispanics, suffer disproportionately high rates of obesity and the related disorders, including cancer. Fifty percent of U.S. African American women are obese. And obesity is higher among lower socioeconomic groups, urban city populations, the Midwest and the South," he says.

The four projects in the Harvard TREC Center span an age continuum that ranges from a cohort of children to two long-term studies of health professionals and includes an interventional clinical trial for survivors of colorectal cancer. In all projects, researchers will be evaluating similar biomarkers of cancer risk and survival.

One interesting feature of two projects is the potential effect of sleep. “There is increasing scientific literature implicating sleep deprivation in increased obesity and type 2 diabetes," Hu says. Changing the circadian rhythms in animals, for example, increases inflammation and insulin resistance and leads to changes in hormones related to appetite and energy regulation. Sleep deprived people have reduced levels of leptin, an appetite suppressing hormone.

In children who have been followed from birth to age 11, a team headed by Elsie Taveras, MD, MPH (HMS), will study how the length and patterns of sleep may correlate with childhood obesity and cancer biomarkers. In another project, Hu and his colleagues will look at the connection between sleep and cancer biomarkers in a group of 750 middle-aged women from the Nurses' Health Study. That project will also evaluate the neighborhood effect and social and built environments. “Obesity and energy balance may mediate the effect of socioeconomic factors and the built environment on cancer," Hu says.

Turning to the Physicians' Health Study, Jing Ma, MD, PhD (BWH), will investigate whether obesity among men diagnosed with prostate cancer has any long-term impact on cancer recurrence and survival. For the fourth project, Jeffrey Meyerhardt, MD, MPH (DFCI), and Jennifer Ligibel, MD (DFCI), will recruit colorectal cancer survivors to test the effects of metformin, a diabetes drug, alone and in combination with exercise on insulin levels. (See Spotlight.)

Leading the way in reframing and reducing cancer disparities

Between them the centers are exploring the complexity of specific pathways through which upstream social factors shape health and are seeking to identify priorities for intervention. Future plans call for expansion on several fronts, including a new Think Tank to link community concerns to the work of DF/HCC investigators, additional collaborations with disease-based research programs, more translational research on the bio-behavioral aspects of cancer risk and disparities, and causal links between stress, discrimination biological pathways and adverse outcomes.

For more information about the Lung Cancer Disparities Center, see http://cancercontrol.cancer.gov/populationhealthcenters/cphhd/centers-hu.html.

For more information about the TREC center, see the national web site at http://www.trecscience.org/.

— Carol Cruzan Morton