Faculty Research Interests

Mark B. Orringer, MD

Dr. Orringer is currently collaborating with David Beer, Ph.D., Director of the Thoracic Surgery Tumor Biology Program to define unique genetic markers in thoracic malignancies which may ultimately have both prognostic and therapeutic implications. This collaborative effort involves harvesting of fresh tumor tissue for DNA and RNA analysis in the thoracic surgery laboratory and concurrent correlation between clinical tumor stage, the presence of particular genetic markers, and prognosis.

Dr. Orringer is involved in a variety of clinical research projects involving assessment of the long-term efficacy of antireflux operations, particularly the combined Collis-Nissen repair, and optimal methods of resection and replacement of the esophagus, particularly using transhiatal esophagectomy and a cervical esophagogastric anastomosis for both benign and malignant disease. In addition, as Director of the Thoracic Oncology Program of the University of Michigan Cancer Center, Dr. Orringer coordinates several multidisciplinary clinical research protocols for the treatment of thoracic malignancies.

David G. Beer, PhD

Our research program is aimed at providing a greater understanding of the cellular and molecular events which are critical to the neoplastic development of esophageal and lung tissue. Normal and neoplastic tissues obtained from surgical resection and established cell lines serve as our model systems. We utilize nearly all types of molecular techniques in our research.

Risk Factors for Cancer Development in Patients with Barrett's Metaplasia: Our work has focused on intestinalized Barrett's metaplasia and the specific properties which put it at risk for developing towards neoplasia. This includes the ability to metabolically activate carcinogens and the presence of important cellular protective mechanisms. We utilize surgical specimens and our ability to place Barrett's metaplasia and normal esophageal tissue into organ culture. Chemoprevention studies are currently underway treating patient's with Barrett's metaplasia with agents which may reduce the further risk of cancer development. We also are investigating the cellular origin of Barrett's metaplasia. Genetic Events During Esophageal Cancer Development: we are identifying and cloning novel genes involved in esophageal adenocarcinoma development. Specific alterations involving gene amplification/loss in these tumors are being examined and may provide genetic markers of prognosis and/or potential responsiveness to chemotherapy or radiation therapy.

Lung Cancer: A major research focus is identifying genetic alterations which influence patient prognosis. We are examining factors which affect tumor cell invasion and metastasis as well as genetic events such as gene amplification and loss. We are employing gene chip and two-dimensional protein analysis as our primary tools for this research.

Andrew C. Chang, MD

Dr. Chang is currently working in collaboration with Dr. David Beer studying the pathogenesis of esophageal cancer. His particular interest is in studying the progression of disease from dysplasia in Barrett's esophagitis to the development of esophageal adenocarcinoma, utilizing microarray analysis and validation in order to identify potential targets for therapy and/or chemoprevention.

Clinical projects under development, in conjunction with the Geriatrics Center, include studies aimed at assessing outcomes after thoracic surgery among elderly patients and devising intervention strategies that will improve the surgical care and resident education of geriatric patients. Efforts are additionally underway to develop specialized computer-based training tools that will facilitate the teaching, assessment, and performance of advanced thoracoscopic surgery.