Basic Sciences





Geisinger Commonwealth School of Medicine
Medical Sciences Building
525 Pine St., Office 3062W, Lab 3064W
Scranton, PA 18509







Youngjin Cho, PhD, is assistant professor of cell biology in the Department of Basic Sciences. The current focus of Dr. Cho’s research is to elucidate the mechanism by which AFAP1, an actin cytoskeleton organizing protein, contributes to lipid metabolism. AFAP1 also plays a role in cancer progression by activating a prominent proto-oncogene called c-Src. Her current research is aimed at increasing our understanding of AFAP1’s role in fatty liver disease as well as diabetes and other metabolic disorders.


Osteoporosis and osteopenia, obesity


Immunology, small group-based learning, undergraduate medical education competency


Regulation of bone formation, regulation of adipogenesis and obesity (physiological role of Src family kinases and their adaptor proteins in bone formation, adipogenesis and lipogenesis), animal model of bone formation and adipogenesis


The actin filament associated protein 1(AFAP1) plays an important role in the organization of the actin cytoskeleton and the localization and activation of c-Src, a prominent proto-oncogene implicated in normal physiology as well as cancer progression. Utilizing an AFAP1 knockout mouse model where the expression of AFAP1 is ablated in every tissue, we have found that AFAP1 is necessary for normal lipid metabolism and trafficking. Mice deficient in AFAP1 have defects in mobilizing triglyceride-enriched vesicle to properly produce milk and display excess lipid accumulation in the liver. The current focus of Dr. Cho’s lab is to elucidate the exact mechanism by which AFAP1 contributes to lipid metabolism, as the knowledge gained from the research directly applies to our understanding of various human diseases including non-alcoholic hepatic steatosis.


1. Cunnick J, Kim S, Hadsell J, Cerra C, Reiser P, Flynn D, Cho Y (corresponding author). (2014) Actin filament-associated protein 1 is required for cSrc activity and secretory activation in the lactating mammary gland. Oncogene. doi:10.1038/onc.2014.205. PMID: 25043309
2. Snyder BN*, Cho Y*, Qian Y, Coad JE, Flynn DC, Cunnick JM. (2011) AFAP1L1 is a novel adaptor protein of the AFAP family that interacts with cortactin and localizes to invadosomes. Eur J Cell Biol 90:376-89. PMID:21333378
3. Clump AC, Yu JJ, Cho Y, Gao R, Jett J, Zot H, Cunnick JM, Snyder B, Clump AC Dodrill M, Gannett P, Coad JE, Shurina R, Figg WD, Reed E, and Flynn DC. (2010) A polymorphic variant of AFAP-110 enhances cSrc activity. Transl Oncol 3:276-285. PMID:20689769
4. Cunnick JM, Schmidhuber S, Chen G, Yu M, Yi SJ, Cho YJ, Kaartinen V, Minoo P, Warburton D, Groffen J, Heisterkamp N. ( 2009) Bcr and Abr cooperate in negatively regulating acute inflammatory responses. Mol Cell Biol 29:5742-5750. PMID:19703997
5. Dorfleutner A, Cho YJ., Vincent D, Cunnick J, Lin H, Weed S, Stehlik C. and Flynn DC. (2008) Phosphorylation of AFAP-110 affects podosome lifespan in A7r5 cells. Journal of Cell Science
121:2394-405. PMID:18577577
6. Flynn DC, Cho YJ, Vincent D, and Cunnick J. (2008) Podosomes and invadopodia: Related structures with common protein components that may promote breast cancer cellular invasion. Breast Cancer: Basic and clinical research 1: 1-13.
7. Kweon SM, Cho YJ, Minoo P, Groffen J, Heisterkamp N. (2008) Activity of the Bcr GTPase-activating domain is regulated through direct protein/protein interaction with the Rho guanine nucleotide dissociation inhibitor. J Biol Chem 283:3023-30. PMID:18070886
8. Cho YJ*, Cunnick J*, Kaartinen V, Groffen J, Heisterkamp N. (2007) Abr and Bcr, two homologous RacGAPs, control multiple cellular functions of murine macrophages. Mol Cell Biol. 27:899-911. PMID:17116687
9. Cunnick J, Kaur P, Cho YJ, Groffen J, Heisterkamp N. (2006) Use of bone marrow-derived macrophages to model murine innate immune responses. J Immunol Methods. 1-2:96-105. PMID:16563426
10. Cho YJ*, Zhang B*, Kaartinen V, Haataja L, de Curtis I, Groffen J, Heisterkamp N. (2005) Generation of rac3 null mutant mice: role of Rac3 in Bcr/Abl-caused lymphoblastic leukemia. Mol Cell Biol. 13:5777-85. PMID:15964830
11. Cho YJ*, Hemmeryckx B*, Groffen J, Heisterkamp N. (2005) Interaction of Bcr/Abl with C3G, an exchange factor for the small GTPase Rap1 through the adapter protein Crkl. Biochem Biophys Res Commun. 4:1276-83. PMID:15982636
12. Park YK, Cho YJ, Ahn TH, Park CK. (1999) Molecular interactions in ribose transport: the binding protein module symmetrically associates with the homodimeric membrane transporter. EMBO J, 18:4149-4156. PMID:10428954