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FAK signaling is critical for ErbB-2/ErbB-3 receptor cooperation for oncogenic transformation and invasion.

Benlimame N, He Q, Jie S, Xiao D, Xu YJ, Loignon M, Schlaepfer DD, Alaoui-Jamali MA - J. Cell Biol. (2005)

Bottom Line: The overexpression of members of the ErbB tyrosine kinase receptor family has been associated with cancer progression.This colocalization requires intact FAK.In summary, distinct FAK signaling has an essential function in ErbB-induced oncogenesis and invasiveness.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine, Lady Davis Institute of the Sir Mortimer B. Davis Jewish General Hospital, McGill University, Montreal, Quebec H3T 1E2, Canada.

ABSTRACT
The overexpression of members of the ErbB tyrosine kinase receptor family has been associated with cancer progression. We demonstrate that focal adhesion kinase (FAK) is essential for oncogenic transformation and cell invasion that is induced by ErbB-2 and -3 receptor signaling. ErbB-2/3 overexpression in FAK-deficient cells fails to promote cell transformation and rescue chemotaxis deficiency. Restoration of FAK rescues both oncogenic transformation and invasion that is induced by ErbB-2/3 in vitro and in vivo. In contrast, the inhibition of FAK in FAK-proficient invasive cancer cells prevented cell invasion and metastasis formation. The activation of ErbB-2/3 regulates FAK phosphorylation at Tyr-397, -861, and -925. ErbB-induced oncogenic transformation correlates with the ability of FAK to restore ErbB-2/3-induced mitogen-activated protein kinase (MAPK) activation; the inhibition of MAPK prevented oncogenic transformation. In contrast, the inhibition of Src but not MAPK prevented ErbB-FAK-induced chemotaxis. In migratory cells, activated ErbB-2/3 receptors colocalize with activated FAK at cell protrusions. This colocalization requires intact FAK. In summary, distinct FAK signaling has an essential function in ErbB-induced oncogenesis and invasiveness.

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Overexpression of ErbB-2, -3, and -2/3 in FAK+/+ and FAK−/− cells. (A) Cells expressing control retroviral particles or ErbB receptors were subjected to Western blotting using specific ErbB antibodies as described in Materials and methods. (B) Cells were fixed and double stained for ErbB-2 and -3 using specific antibodies and were examined by immunofluorescence microscopy. Note that FAK−/− and FAK+/+ control cells do not express any ErbB-2 or -3 receptors, whereas FAK−/−-2/3 and FAK+/+-2/3 exhibited strong labeling for both receptors. Bar, 40 μm. (C) Cells were serum starved for 24 h and kept unstimulated (control, C) or were stimulated with 20 ng/ml EGF (E) or HRG (H) for 10 min. Cell lysates were immunoprecipitated with anti-ErbB, and the blots were probed using antiphosphotyrosine antibody and reprobed with the corresponding ErbB-specific antibody.
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fig1: Overexpression of ErbB-2, -3, and -2/3 in FAK+/+ and FAK−/− cells. (A) Cells expressing control retroviral particles or ErbB receptors were subjected to Western blotting using specific ErbB antibodies as described in Materials and methods. (B) Cells were fixed and double stained for ErbB-2 and -3 using specific antibodies and were examined by immunofluorescence microscopy. Note that FAK−/− and FAK+/+ control cells do not express any ErbB-2 or -3 receptors, whereas FAK−/−-2/3 and FAK+/+-2/3 exhibited strong labeling for both receptors. Bar, 40 μm. (C) Cells were serum starved for 24 h and kept unstimulated (control, C) or were stimulated with 20 ng/ml EGF (E) or HRG (H) for 10 min. Cell lysates were immunoprecipitated with anti-ErbB, and the blots were probed using antiphosphotyrosine antibody and reprobed with the corresponding ErbB-specific antibody.

Mentions: Both FAK+/+ and FAK−/− cells express very low levels of ErbB-1, but -2, -3, and -4 were not detected by Western blot analysis (Fig. 1 A), making this model very appropriate to address the biological impact of ErbB overexpression. We focused on ErbB-2 and -3 overexpression based on preliminary data showing that FAK-proficient cells cooverexpressing the ErbB-2 and -3 combination were the most invasive in vivo and on the Boyden chamber assay compared with cells overexpressing the other ErbB receptor combinations (Fig. S1, available at http://www.jcb.org/cgi/content/full/jcb.200504124/DC1). FAK+/+ and FAK−/− cells were stably transduced with a retrovirus that expresses ErbB-2 or -3 receptor and enhanced GFP. Receptor expression in cells that were transduced with control retroviral particles or particles encoding ErbB-2 and/or -3 receptors was confirmed by Western blot assay (Fig. 1 A) and immunofluorescence analysis (Fig. 1 B).


FAK signaling is critical for ErbB-2/ErbB-3 receptor cooperation for oncogenic transformation and invasion.

Benlimame N, He Q, Jie S, Xiao D, Xu YJ, Loignon M, Schlaepfer DD, Alaoui-Jamali MA - J. Cell Biol. (2005)

Overexpression of ErbB-2, -3, and -2/3 in FAK+/+ and FAK−/− cells. (A) Cells expressing control retroviral particles or ErbB receptors were subjected to Western blotting using specific ErbB antibodies as described in Materials and methods. (B) Cells were fixed and double stained for ErbB-2 and -3 using specific antibodies and were examined by immunofluorescence microscopy. Note that FAK−/− and FAK+/+ control cells do not express any ErbB-2 or -3 receptors, whereas FAK−/−-2/3 and FAK+/+-2/3 exhibited strong labeling for both receptors. Bar, 40 μm. (C) Cells were serum starved for 24 h and kept unstimulated (control, C) or were stimulated with 20 ng/ml EGF (E) or HRG (H) for 10 min. Cell lysates were immunoprecipitated with anti-ErbB, and the blots were probed using antiphosphotyrosine antibody and reprobed with the corresponding ErbB-specific antibody.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2171271&req=5

fig1: Overexpression of ErbB-2, -3, and -2/3 in FAK+/+ and FAK−/− cells. (A) Cells expressing control retroviral particles or ErbB receptors were subjected to Western blotting using specific ErbB antibodies as described in Materials and methods. (B) Cells were fixed and double stained for ErbB-2 and -3 using specific antibodies and were examined by immunofluorescence microscopy. Note that FAK−/− and FAK+/+ control cells do not express any ErbB-2 or -3 receptors, whereas FAK−/−-2/3 and FAK+/+-2/3 exhibited strong labeling for both receptors. Bar, 40 μm. (C) Cells were serum starved for 24 h and kept unstimulated (control, C) or were stimulated with 20 ng/ml EGF (E) or HRG (H) for 10 min. Cell lysates were immunoprecipitated with anti-ErbB, and the blots were probed using antiphosphotyrosine antibody and reprobed with the corresponding ErbB-specific antibody.
Mentions: Both FAK+/+ and FAK−/− cells express very low levels of ErbB-1, but -2, -3, and -4 were not detected by Western blot analysis (Fig. 1 A), making this model very appropriate to address the biological impact of ErbB overexpression. We focused on ErbB-2 and -3 overexpression based on preliminary data showing that FAK-proficient cells cooverexpressing the ErbB-2 and -3 combination were the most invasive in vivo and on the Boyden chamber assay compared with cells overexpressing the other ErbB receptor combinations (Fig. S1, available at http://www.jcb.org/cgi/content/full/jcb.200504124/DC1). FAK+/+ and FAK−/− cells were stably transduced with a retrovirus that expresses ErbB-2 or -3 receptor and enhanced GFP. Receptor expression in cells that were transduced with control retroviral particles or particles encoding ErbB-2 and/or -3 receptors was confirmed by Western blot assay (Fig. 1 A) and immunofluorescence analysis (Fig. 1 B).

Bottom Line: The overexpression of members of the ErbB tyrosine kinase receptor family has been associated with cancer progression.This colocalization requires intact FAK.In summary, distinct FAK signaling has an essential function in ErbB-induced oncogenesis and invasiveness.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine, Lady Davis Institute of the Sir Mortimer B. Davis Jewish General Hospital, McGill University, Montreal, Quebec H3T 1E2, Canada.

ABSTRACT
The overexpression of members of the ErbB tyrosine kinase receptor family has been associated with cancer progression. We demonstrate that focal adhesion kinase (FAK) is essential for oncogenic transformation and cell invasion that is induced by ErbB-2 and -3 receptor signaling. ErbB-2/3 overexpression in FAK-deficient cells fails to promote cell transformation and rescue chemotaxis deficiency. Restoration of FAK rescues both oncogenic transformation and invasion that is induced by ErbB-2/3 in vitro and in vivo. In contrast, the inhibition of FAK in FAK-proficient invasive cancer cells prevented cell invasion and metastasis formation. The activation of ErbB-2/3 regulates FAK phosphorylation at Tyr-397, -861, and -925. ErbB-induced oncogenic transformation correlates with the ability of FAK to restore ErbB-2/3-induced mitogen-activated protein kinase (MAPK) activation; the inhibition of MAPK prevented oncogenic transformation. In contrast, the inhibition of Src but not MAPK prevented ErbB-FAK-induced chemotaxis. In migratory cells, activated ErbB-2/3 receptors colocalize with activated FAK at cell protrusions. This colocalization requires intact FAK. In summary, distinct FAK signaling has an essential function in ErbB-induced oncogenesis and invasiveness.

Show MeSH
Related in: MedlinePlus