Researcher’s Profile

Tom K. Hei, PhD

Vice-Chairman of Radiation Oncology

In risk assessment studies, in vitro neoplastic transformation assays based on rodent fibroblasts are use to obtain quantitative dose response data for environmental carcinogens such as tobacco smoke, radon, asbestos fibers, and heavy metals. Immortalized human bronchial and breast epithelial cell models are used to examine the molecular mechanisms involved in the multistage nature of human carcinogenesis. Activation of oncogenes, loss of tumor suppressor genes, altered signal transduction pathways in radon and asbestos induced bronchial carcinogenesis are currently funded research projects. Emphases are on mechanisms of fiber mutagenesis, effects of reactive oxygen species in fiber toxicity, and the synergistic interaction of asbestos with other environmental carcinogens such as radon and cigarette smoke.

Research Statement: 

Environmental carcinogenesis, specifically mechanisms of chemical and radiation carcinogenesis mutagenesis at the cellular and molecular level. Fiber toxicology, particularly, the how and why of mineral fibers, including asbestos an other man-made fibers, in causing lung fibrosis and cancers of the lung and peritoneum. Molecular mechanisms of mutagenesis by various environmental carcinogens.