What are the center's research initiatives?
The Swetland Center’s research spans a number of areas that contribute to emerging understanding of our health and the environment. Dr. Li's translational research focus includes studies at the molecular, individual, and population levels. Areas of focus and specific research studies are described below.
- Carcinogenesis: How Normal Cells become Cancer
- Chemoprevention: Finding Ways to Stop or Delay Cancer Development
- Energy Imbalance: Finding Links to Cancer
- Gene-Environment Interactions
Carcinogenesis: How Normal Cells Become Cancer
Carcinogenesis is the process by which normal cells become cancer cells. Research in this area seeks to understand that process with a goal of finding opportunities for prevention and cure.
Is retinol binding protein 4 a link between adiposity and cancer?
A possible link between obesity and cancer development may be a binding protein called Retinol Binding Protein 4 (RBP4). This protein is normally created in the liver, but it can also be created in fat cells. It typically functions to transport molecules throughout the body, but when it is present in high levels, it has been shown to impact cancer-causing pathways. Therefore, as fat cells increase, as in obesity, so does the risk of developing cancer.
Serum levels of retinol-binding protein 4 (RBP4) and risk of colon adenoma.
RBP4 is a transport molecule found circulating in the bloodstream. Its possible linkage to obesity and colon cancer was determined via a case study. It was found that patients with a high BMI had higher levels of circulating RBP4 when compared to patients with a lower BMI. It was also found that those with higher levels of RBP4 had a significant association risk for colon adenoma.
Chemoprevention: Finding Ways to Stop or Delay Cancer
These studies explore ways to prevent or limit cancer using drugs, chemical agents or food nutrients.
Combined use of vitamin D3 and metformin exhibits synergistic chemopreventive effects on colorectal neoplasia in rats and mice.
Vitamin D3 and metformin have typically been used for regulating metabolism and diabetes respectively. Their possible combined beneficial effect against colon cancer was tested. This was done using two different mouse studies in which colon cancer was induced. When the mice were treated with combination drug therapy, there was a beneficial effect against the development of early colon cancer. This suggests that these drugs may be chemopreventive for colon cancer.
Energy Imbalance: Finding Links to Cancer
An imbalance between the amount of food we eat and the amount of energy we use has shown to be linked to cancer. These studies explore that connection and may show potential ways to decrease risk.
Prevalence of metabolic syndrome among urban community residents in China.
Metabolic syndrome (MetS) is a collection of metabolic risk factors that may advance to diabetes, heart disease, and cancer. There has recently been a rapid rise in obesity and hypertension among China’s population, however there is limited Mets data. Metabolic risk factors were analyzed in a large-scale study of adults and the prevalence of MetS was recorded based on age, smoking, family history of diabetes and education. The results indicate that Mets is highly prevalent, reaching epidemic proportions in urban communities.
Insulin Resistance, Central Obesity, and Risk of Colorectal Adenomas.
Limited data exists on the linkage between insulin resistance (IR) and colorectal adenomas, however there have been indications that IR may directly result in obesity-related colorectal cancer. In order to test this relationship, an IR index (HOMA-IR) and waist-to-hip ratios (WHR) were used in comparison to screening colonoscopies in a large-scale study. The results indicate that those with increased levels of IR and higher WHR were more likely to have adenomas.
Short duration of sleep increases risk of colorectal adenoma.
There have been multiple associations between poor sleep quality and increased risk of obesity, cardiovascular disease, diabetes and total mortality. In order to determine if any linkage exists between sleep quality and colorectal cancer, a large-scale study of patients undergoing screening was completed. The study found that those who averaged less than six hours of sleep a night were 50 percent more likely to develop colorectal cancer. This finding indicates that sleep duration is a significant risk factor for colorectal cancer.
Gene mutations that lead to disease can be passed from parents to their children. Identification of these mutations allows for better screening of patients as well as potential new drug treatments.
Genome-wide association study of colorectal cancer identifies six new susceptibility loci.
There has long been an association between genetics and risk of developing colorectal cancer, however the exact location of where most of these genes lay within the DNA is vastly unknown. Entire DNA sequencing was done for patients with and without cancer. This revealed six new susceptibility locations with statistically significant data. These findings may provide possible insight into the underlying molecular causes of colorectal cancer.
A genome-wide association study for colorectal cancer identifies a risk locus in 14q23.1.
In order to determine whether more colorectal cancer-causing genes exist entire DNA sequencing was completed for over 30,000 patients. A specific gene and its location were found in cancerous colon tissue of these patients. It was extrapolated from this data that the gene encoded a protein-coding gene involved in survival and proliferation of cancer cells.
Screening tests identify disease at an early stage, often before symptoms or signs develop. Research in this area is important to better identify and treat disease.
Stool DNA-based versus colonoscopy-based colorectal cancer screening: Patient perceptions and preferences.
In order to determine use viability of stool DNA (sDNA)-based versus colonoscopy-based colorectal cancer screening, patient opinion was considered. 623 patients were surveyed across multiple ethnicities. The results indicated that participants found the sDNA test more suitable than a colonoscopy. These findings may allow for reduced racial disparities in colorectal cancer.
Cross-cancer genome-wide analysis of lung, ovary, breast, prostate and colorectal cancer reveals novel pleiotropic associations.
In order to determine whether there is a widespread relation between common pathways influencing multiple cancers, a two-stage approach was conducted. The entire genome was evaluated to find associations between markers for different forms of cancer. Four distinct associations were found relating gene mutations from one cancer to another.