Abstract
Integrins are adhesion receptors that transmit signals bidirectionally across the plasma membrane. In our previous report we have shown that the squamous lung cancer cell line, Calu‐1, binds to collagen type IV (Coll IV) through β1‐integrin and results in phosphorylation of focal adhesion kinase (FAK) (Ann Thorac Surg 2004; 78:450‐7). Considering the critical role of FAK in cell migration, proliferation, and survival, here we investigated potential mechanisms of its activation and regulation in Calu‐1 cells. We observed the phosphorylation of Tyr397 of FAK (the autophosphorylation site of FAK) and paxillin, the immediate downstream substrate of FAK following the adhesion of Calu‐1 cells to Coll IV. FAK remains phosphorylated during proliferation either on Coll IV or on uncoated plates for 72 h, as determined by peroxivanadate treatment. Exposure of Calu‐1 cells with 60 μM genistein, reduces FAK phosphorylation (7.6 fold) and cell proliferation. Extracellular signal regulated kinases (ERKs) were also phosphorylated after Coll IV attachment. Disruption of Calu‐1 cell cytoskeleton integrity by 1–5 μM Cytochalasin D resulted in the inhibition of cell adhesion (50% to 75%, p<0.19–6.6×10‐7) and ERKs phosphorylation (2 fold) without any effect on FAK phosphorylation. Protein Kinase C inhibitor, Calphostin C at 100 and 250 nM concentrations did not block Coll IV induced FAK phosphorylation, but activated the ERKs in a dose dependent manner. β1‐integrin is essential for Coll IV induced FAK activation, but it is not physically associated with FAK as determined by immunodetection assay. Collectively, this report defines the existence of multiple and potentially parallel Coll IV/β1‐integrin mediated signaling events in Calu‐1 cells, which involve FAK, ERKs, and PKC.
Keywords: lung cancer, metastasis, collagen type IV, focal adhesion kinase, extracellular signal regulated kinases, protein kinase C
References
- 1. Liotta LA, Stetler‐Stevenson WG. Tumor invasion and metastasis: an imbalance of positive and negative regulation. Cancer Res. 1991; 51: 5054–9. [PubMed] [Google Scholar]
- 2. Furuta SM, Ilic D, Kanazawa S, Takeda N, Yamamto T, Aizawa S. Mesodermal defect in late phase of gastrulation by a targeted mutation of focal adhesion kinase FAK. Oncogene. 1995; 11: 1989–95. [PubMed] [Google Scholar]
- 3. Guan J‐L, Shalloway D. Regulation of pp 125FAK both by cellular adhesion and by oncogenic transformation. Nature. 1992; 358: 690–2. [DOI] [PubMed] [Google Scholar]
- 4. Sanders MA, Basson MD. Collagen IV‐dependent ERK activation in human Caco‐2 intestinal epithelial cells requires focal adhesion kinase. J Biol Chem. 2000; 275: 38040–7. [DOI] [PubMed] [Google Scholar]
- 5. Akasaka T, van Leeuwen RL, Yoshinaga IG, Mihm MC, Byers HH. Focal adhesion kinase (p125FAK) expression correlates with motility of human melanoma cell lines. J Invest Darmatol. 1995; 105: 104–8. [DOI] [PubMed] [Google Scholar]
- 6. Weiner TM, Liu ET, Craven RJ, Cance WG. Expression of focal adhesion kinase gene and invasive cancer. Lancet 1993; 342: 1024–5. [DOI] [PubMed] [Google Scholar]
- 7. Owens LV, Xu L, Craven RG, Dent GA, Weiner TM, Kornberg L, Liu E, Cance WG. Overexpression of the focal adhesion kinase (p125FAK) in invasive human tumors. Cancer Res. 1995; 55: 2752–5. [PubMed] [Google Scholar]
- 8. Richardson A, Malik RK, Hildebrand JD, Parsons JT. Inhibition of cell spreading by expression of the C‐terminal domain of focal adhesion kinase (FAK) is rescued by coexpression of Src or catalytically inactive FAK: a role for paxillin tyrosine phosphorylation. Mol Cell Biol. 1997; 17: 6906–14. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9. Schlaepfer DD, Hunter T. FAK overexpression enhances Ras‐dependent integrin signaling to ERK2/mitogen‐activated protein kinase throgh interactions with and activation of c‐Src. J Biol Chem. 1997; 272: 13189–95. [DOI] [PubMed] [Google Scholar]
- 10. Schalaepfer DD, Jones KC, Hunter T. Multiple Grb2‐mediated integrin stimulated signaling pathways to ERK2/mitogen‐activated protein kinase: Summation of c‐Src and focal adhesion kinase‐initiated tyrosine phosphorylation events. Mol Cell Biol. 1998; 18: 1–32. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11. Miyamoto S, Teramoto H, Coso OA. Integrin function: molecular hierarchies of cytoskeletal and signaling molecules. J Cell Biol. 1995; 131: 791–05. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12. Clark EA, Hynes RO. Ras activation is necessary for integrin‐mediated activation of extracellular signal regulated kinase 2 and cytosolic phospholipase A2 but not for cytoskeletal organization. J Biol Chem. 1996; 271: 14814–8. [DOI] [PubMed] [Google Scholar]
- 13. Lewis JM, Cheresh DA, Schwartz MA. Protein kinase C regulates αvβ5‐dependent cytoskeletal associations and focal adhesion kinase phosphorylation. J Cell Biol. 1996; 134: 1323–32. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14. Mukhopadhay NK, Gillchrist D, Gordon JG, Cheng CJ, Bueno R, Lu ML, Salgia R, Sugarbaker DJ, Jaklitsch MT. Integrin dependent tyrosine phosphorylation is a key regulatory event in collagen IV mediated adhesion and proliferation of human lung cancer cell line. Calu-1. Ann Thorac Surg. 2004; 78: 450–7. [DOI] [PubMed] [Google Scholar]
- 15. Sakamoto M, Ino Y, Ochiai A, Kanai Y, Akimoto S, Hirohashi S. Formation of focal adhesion and spreading of polarized human colon cancer cells in association with tyrosine phosphorylation of paxillin in response to phorbol ester. Lab Invest. 1996; 74: 199–08. [PubMed] [Google Scholar]
- 16. Miles AJ, Skubitz AP, Furcht LT, Fields GB. Promotion of cell adhesion by single‐stranded and triplehelical peptide models of basement membrane collagen alpha 1(IV) 531–543. Evidence for conformationally dependent and conformationally independent type IV collagen cell adhesion sites. J Biol Chem. 1994; 269: 30939–45. [PubMed] [Google Scholar]
- 17. Schaller MD, Hildebrand JD, Shannon JD, Fox JW, Vines RR, Parsons JT. Autophosphorylation of the focal adhesion kinase, pp125FAK, directs SH2‐dependent binding of pp60src. Mol Cell Biol. 1994; 14: 1680–8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18. Richardson A, Malik RK, Hildebrand JD, Parsons JT. Inhibition of cell spreading by expression of the Cterminal domain of focal adhesion kinase (FAK) is rescued by coexpression of Src or catalytically inactive FAK: a role for paxillin tyrosine phosphorylation. Mol Cell Biol. 1997; 17: 6906–14. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19. Schlaepfer DD, Hanks SK, Hunter T. Integrin‐mediated signal transduction linked to Ras pathway by Grb2 binding to focal adhesion kinase. Nature. 1994; 372: 786–91. [DOI] [PubMed] [Google Scholar]
- 20. Chen HC, Guan JL. Association of focal adhesion kinase with its potential substrate phosphatidylinositol 3‐kinase. Proc Natl Acad Sci USA. 1994; 91: 10148–52. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21. Polte ZTR, Hanks SK. Interaction between focal adhesion kinase and Crk‐associated tyrosine kinase substrate p130cas. Proc Natl Acad Sci USA. 1995; 92: 10678–82. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22. Tamura M, Gu J, Tran H, Yamada KM. PTEN gene and integrin signaling in cancer. J Natl Cancer Inst. 1999; 91: 1820–8. [DOI] [PubMed] [Google Scholar]
- 23. Renshaw MW, Price LS, Schwartz MA. Focal adhesion kinase mediates the integrin signaling requirement for growth factor activation of MAP kinase. J Cell Biol. 1999; 147: 611–8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 24. Zhang L, Bewick M, Lafrenie RM. Role of Raf‐1 and FAK in cell density dependent regulation of integrindependent activation of MAP kinase. Carcinogenesis. 2002; 23: 1251–8. [DOI] [PubMed] [Google Scholar]
- 25. Klemke RL, Cai S, Giannini AL, Gallagher PJ, de Lanerolle P, Cheresh DA. Regulation of cell motility by mitogen‐activated protein kinase. J Cell Biol. 1997; 137: 481–92. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26. Ilic D, Furuta Y, Kanazawa S, Takeda N, Sobue K, Nakatsji N, Nomur S, Fujimoto J, Okada M, Yamamoto T. Reduced cell motility and enhanced focal adhesion contact formation in cells from FAK‐deficient mice. Nature 1995; 377: 539–44. [DOI] [PubMed] [Google Scholar]
- 27. Gilmore AP, Romer LH. Inhibition of focal adhesion kinase (FAK) signaling in focal adhesions decreases cell motility and proliferation. Mol Biol Cell. 1996; 7: 1209–24. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 28. Vouri K, Ruoslanti E. Actvation of protein Kinase C proceeds α5β1 integrin‐mediated cell spreading on fibronectin. J Biol. Chem. 1993; 268: 459–62. [PubMed] [Google Scholar]