Functional analysis of focal adhesion kinase (FAK) reduction by small inhibitory RNAs.
The focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that localizes to the points of cell contact with the extracellular matrix, called focal adhesions. Many factors induce tyrosine phosphorylation of FAK including growth factors, neuropeptides and integrin-dependent adhesion to the extracellular matrix. FAK has been implicated in several cellular processes such as invasion, motility, proliferation and apoptosis. In addition, FAK expression was shown to be elevated in a number of different human cancers, suggesting a role in the development of malignancy. We examined the biological functions of FAK using small inhibitory RNAs (siRNA) in cancer cells. Although FAK siRNA reduced the FAK protein levels by approximately 70% in several cancer cell lines, there was no clear evidence of apoptosis. However, in clonogenic and soft-agar assays in H1299, a lung cancer cell line, FAK siRNA treatment led to a 43% to 55% decrease in colony formation. Furthermore, FAK siRNA-treated cells displayed a decrease in migration when serum or EGF (epidermal growth factor) were used as chemo-attractants. Our results demonstrated that inhibition of FAK protein leads to alterations in cell growth and migration.
Han
Edward Kyu-Ho
EK
Abbott Laboratories, Global Pharmaceutical Research Division, Cancer Division, 100 Abbott Park Rd, Abbott Park, IL 60064, USA. edward.k.han@abbott.com
Mcgonigal
Thomas
T
Wang
Jieyi
J
Giranda
Vincent L
VL
Luo
Yan
Y
D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D014411:Neoplastic Stem Cells; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics*; D014162:Transfection
D034741:RNA, Small Interfering; D004815:Epidermal Growth Factor; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496050:PTK2 protein, human