DESCRIPTION (provided by applicant): The candidate, Dr. Ha, has demonstrated a long standing history of commitment to research and academic otolaryngology. This career development award, under the mentorship of Drs. David Sidransky and Joseph Califano is focused on the basic mechanisms underlying adenoid cystic carcinoma (ACC). ACC is a salivary gland malignancy characterized by persistent local, regional, and distant recurrence despite complete surgical resection and adjuvant radiotherapy. Attempts at improving loco regional control with chemotherapy have been disappointing, and to date, no systemic agent improves control of regional or distant metastases. Better characterization of the genetic alterations involved in ACC tumorigenesis will give us insight into the selection of effective adjuvant therapies or the development of novel therapy. Promoter hypermethylation as a means of tumor suppressor gene silencing is a significant factor in solid tumor carcinogenesis. We have preliminary evidence that promoter hypermethylation is an important means of tumor suppressor gene inactivation in ACC. The candidate proposes to evaluate commonly methylated tumor suppressor genes in an expanded cohort of ACC samples as well as perform genome wide screening in ACC cell lines in an effort to identify novel methylated genes. Functional and clinical correlation will then be applied to evaluate the biologic significance and prognostic value of these inactivated genes. The goal of this work is to comprehensively analyze the role of promoter hypermethylation in ACC. The impact on public health lies in establishing this groundwork that will lead to the identification of important biomarkers of tumor behavior and possible avenues of therapeutic intervention in the treatment of this disease. The process of performing these experiments will provide the candidate with the necessary guidance, coursework, and practical training towards becoming an independent investigator as well as furthering the basic science knowledge of adenoid cystic carcinoma.