Preliminary Validation of Biomarkers Predictive of Barrett's Esophagus Progression to Dysplasia and Adenocarcinoma
Recognizing that novel potential biomarkers are continually being identified and will need to be validated in a rapid, efficient, and scientifically rigorous manner, the NCI has made an enormous commitment to the development of a network that will facilitate biomarker development and validation in multiple organ sites. As part of the National Cancer Institute-funded Early Detection Research Network (EDRN), the Great Lakes-New England Clinical Epidemiological Center (GLNE CEC) proposes a research program that provides the structure for validating and discovering potential surrogate endpoint biomarkers ("biomarkers"). Although examples of such biomarkers are currently in clinical use (i.e. CEA, CA-125), there are limitations to all of them. Our consortium focuses specifically on gastrointestinal neoplasia.
This phase of the proposed research has three goals:
1. Establish the feasibility of measuring the biomarkers in a multi-center clinical trial.
2. Estimate the variance of the biomarkers in cohorts defined by sex, race, age and histologic diagnosis (non-Barrett’s controls, Barrett’s intestinal metaplasia, Barrett’s intestinal dysplasia [low and high-grade] and adenocarcinoma).
3. Determine if the distributions of the biomarkers differ significantly among patients with different histologic diagnoses.
In this protocol, biological samples will consist of serum, plasma, urine, and biopsies from Barrett’s esophagus (metaplasia, low and high-grade dysplasia) patients, from patients with esophageal adenocarcinoma, and from non-Barrett’s controls. Samples will be assayed for villin, p53, Hsp27, cyclooxygenase-2, and Cyclin D1. Samples will also be used for two biomarker discovery projects, one exploring genetic expression using genomic microarrays and a second using two-dimensional gene arrays to discover and characterize amplified proteins associated with esophageal carcinogenesis. Fifty subjects will be studied in each stratum with an estimated total of 300 subjects. If a given biomarker, or panel of markers, is shown in these studies to be potentially reliable, future phases of this research will focus on validation of the marker in a larger cross-sectional cohort studied longitudinally.