Division of Experimental Pathology
Yong Kook Kwon, Ph.D.
Rm. S446, S-BST
200 lothrop street
Pittsburgh, PA 15261
The main focus of the Dr.DeFrances's lab is to elucidate the role of PIK3IP1 (phosphatidylinositol-3-kinase interacting protein 1) in PI3-kinase signal transduction pathway.
Our lab has discovered that PIK3IP1 modulates PI3-kinase by virtue of a region of homology it shares with the p85 regulatory subunit of PI3-Kinase.
PIK3IP1 binds to the catalytic p110 PI3-kinase subunit and downregulates its enzymatic activity in vitro and in vivo. The expression levels of PIK3IP1 in human liver tumors were reduced. In transgenic mice, overexpression of PIK3IP1 in hepatocytes suppressed HCC development and limited hepatocyte proliferation.
We perform biochemical experiments to unveil the molecular mechanism of the inhibitory function of PIK3IP1.
In addition, we investigate the physiological function of PIK3IP1 in hepatocytes by using a conditional knock-out mouse model.