According to CDC, the rate of developing new stomach cancer in Hispanics was 3.7% more than that for NHWs with an almost two-fold increase in mortality. From 1992 to 2011, the incidence of stage IV gastric cancer increased 4.2% among young Hispanic men and the median survival rate of patients with gastric carcinoma in Hispanics being only 51 months compared to 99 months for NHWs. The prevalence of H. pylori infection within Hispanics (30.3%) is three-fold higher than NHWs (9.2%) and this is considered as one of the main reasons of high gastric cancer rate among Hispanics. The goal of this project is to develop an in vivo (Fluorescence Molecular Tomography/FMT), a gastric microbiome and in vitro (electrochemical biosensor) analysis technology to detect nitroso compound, a metabolic chemical secreted by H. Pylori, to screen the potential risk of gastric cancer among Hispanic. We hypothesize that early detection of nitroso compound among Hispanic can prevent the risk of gastric cancer and mitigate in early ahead.  The goal of this project is to (1) delineate the effect of nitroso compound in gastric microbiome among Hispanic and NHWs. Collecting the microbes from the stomach of Hispanic and NHW gastric cancer patients, we will use proteomic analysis to identify the nitroso compounds responsible for the severity of gastric cancer and disparity. (2) Develop an electrochemical biosensor to analysis nitroso compound. For in vitro screening, we envision to develop an electrochemical sensor-based tools to quantify the amount of nitroso compound within the gastric juice be collected from the gastric cancer. (3) To validate the as developed tools utilizing gastric juices collected from patients. For in vivo imaging, we aim to develop a nitroso compound specific near-infrared FMT imaging nanoprobe to detect and assess the severity of gastric cancer noninvasively in a nitroso-compound induced animal model of gastric cancer model.

Impact: The development of early detection modality will facilitate to screening a larger group of Hispanic population yearly to identify individuals who may be at risk or at early stage of gastric cancer.