Cancer Cell Biology
Area of interest
Claudins are the major structural and functional components of tight junctions and are widely expressed in epithelial and endothelial cells and they show tissue-specific distribution patterns. Altered expression and distribution of different claudins have been found in a wide variety of human cancer. Claudin-7 is highly expressed in lung and kidney. Deletion of claudin-7 gene in mice (claudin-7-/-) resulted in hyperproliferation of lung alveolar epithelial cells and the infiltration of neutrophilic leukocytes. While homozygous claudin-7-/- mice die within two weeks after birth, heterozygous claudin-7+/- mice showed an increased incidence of developing lung and kidney tumors. Based on these observation, we are testing the hypothesis that claudin-7 may play a role as a tumor suppressor in cancer.
Lung cancer accounts for more than one-fourth of all cancer deaths and is the leading cause of cancer death worldwide for both men and women. In our current research, we are using a variety of cell based assays to determine if the properties of cell cycle, apoptosis, and cell adhesion and invasion are altered when claudin-7 is stably expressed in human lung cancer cell line NCI-H1299. We are investigating whether claudin-7 expression can suppress NCI-H1299 cell growth in athymic nude mice. We are also analyzing the growth and metastatic properties of Lewis Lung Cancer cell line (LLCL1) with or without stably expressing clauidn-7 after they are inoculated into our heterozygous claudin-7+/- mice, to determine if claudin-7 expression is sufficient to inhibit LLC1 tumor growth in an immuno-competent mouse model.
Identification of claudin-7 as a tumor suppressor and to understand its mechanisms in inhibiting cancer cell growth will help shed lights on how to block lung cancer from progression to metastasis, and therefore, have significant implications for lung cancer therapy.
Awards and Honors
- 1989 Grass Foundation Scholarship recipient, Hopkins Marine Station of Stanford University
- 1991 Travel Award for International Gap Junction Conference, Asilomar, CA
- 1992 Travel Award for 32nd ASBMB/Biophysical Society Joint Meeting, Houston, TX
- 1994-1995 NIH Fellowship recipient
- 1996 Travel Award for International Gap Junction Conference, France. (Invited Speaker)
- 2000 Travel Award for Keystone Symposia. Intercellular Junction. (Invited Speaker)
- 2003-2005 Faculty Research Award from East Carolina University Brody School of Medicine
- 2005-2006 Faculty Author Recognition Award Division of Health Sciences at East Carolina University
- 2007-2008 Research Development Award from the Division of Research and Graduate Studies of East Carolina University