title: GRP78 promotes the invasion of pancreatic cancer cells by FAK and JNK.
abstract: The major characteristics of pancreatic cancer are its excessive local invasion and early systemic dissemination. The glucose-regulated protein is over-expressed in many human cancers including pancreatic cancer and correlated with invasion and metastasis in many cancers. To investigate the effect of Grp78 on the invasion of pancreatic cancer, we used western blot and Transwell assay. We found Grp78 is expressed at lower levels in capan-2 and higher expressed in MiaPaCa-2 cells, and Grp78 expression levels were correlated with the invasion potentials of tumor cells. Then,we increased the expression of Grp78 in capan-2 cells and decreased the expression of Grp78 in MiaPaCa-2 cells. We found that over-expression of Grp78 caused significant increase in the expression of TIMP-1, TIMP-2, MMP-14, MMP-2, and MMP-9 in Capan-2 cells. Consistently, knockdown of Grp78 decreased the expression of them in MiaPaCa-2 cells. Gelatin zymography showed Grp78 over-expression stimulated the activities of MMP-2 and MMP-9, while GRP78 knockdown reduced the activities of MMP-2 and MMP-9. Cytoskeleton staining showed that knockdown of Grp78 caused a marked increase in cytoskeleton F-actin stress fibers in MiaPaCa-2 cells. Consistently, GRP78 knockdown hyperactivated RhoA and inhibited significantly Rac activity. Grp78 over-expression decreases the RhoA and stimulated Rac activity. We also found that Grp78 modulated FAK and JNK signaling pathways. Over-expression of GRP78 in Capan-2 activated FAK and JNK. Finally, we demonstrated that knockdown of FAK by shRNA in combination with blockade of JNK signaling pathway with SP600125 completely inhibited GRP78-induced cancer cell invasion. GRP78 is involved in the regulation of pancreatic cancer invasion. FAK and JNK are the key downstream effectors of GRP78.
authors.affiliation: Gastrointestinal Surgery Department, First Hospital of China Medical University, No. 92 Bei'er Road, Heping District, Shenyang, Liaoning Province, People's Republic of China, lhd373271@sohu.com.
authors.forename: X P
authors.initials: XP
authors.lastname: Yuan
authors.forename: Ming
authors.initials: M
authors.lastname: Dong
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: J P
authors.initials: JP
authors.lastname: Zhou
mesh_terms: D000873:Anthracenes / Q000494:pharmacology; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002465:Cell Movement; D000091342:Endoplasmic Reticulum Chaperone BiP; D051417:Focal Adhesion Kinase 1 / Q000235:genetics / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D053511:Matrix Metalloproteinase 14 / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D008856:Microscopy, Fluorescence; D009361:Neoplasm Invasiveness; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D034622:RNA Interference; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism
chemical_list: D000873:Anthracenes; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; C432165:pyrazolanthrone; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; D048031:JNK Mitogen-Activated Protein Kinases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D053511:Matrix Metalloproteinase 14