Culture of human cervical cancer cells, SiHa, in the presence of fibronectin activates MMP-2.
OBJECTIVE
Several studies indicate that integrin receptors are involved in the regulation of matrix metalloproteinase (MMP) expression. Integrin-ECM ligand interaction leads to phosphorylation of focal adhesion kinase (FAK) and activation of mitogen activated protein kinase pathways. In this present communication, we cultured human cervical cancer cells, SiHa, in the presence of fibronectin to study fibronectin-integrin mediated modulation of MMP activity.


METHODS
SiHa cells were cultured in serum-free medium (SFCM) in the presence of fibronectin, SFCM was collected and gelatin zymography was performed. Western blot, RT-PCR and immunocytochemistry were performed with SiHa cells cultured in the presence of fibronectin.


RESULTS
The culture of SiHa cells in the presence of 50 microg/1.5 ml fibronectin led to expression of pro-MMP-9 and activation of MMP-2 within 2 h. When cells were treated with ERK inhibitor (PD98059) and grown in the presence of fibronectin MMP-2 activation was partially inhibited, but when cells were treated with PI-3K inhibitor (LY294002) and grown in the presence of fibronectin MMP-2 activation was appreciably reduced. Tyrosine phosphorylation of FAK, PI-3K and ERK and nuclear trafficking of ERK were increased in SiHa cells grown in the presence of fibronectin. Increased MT1-MMP mRNA expression and processing of MT1-MMP were also observed in SiHa cells grown in the presence of fibronectin.


CONCLUSIONS
Our findings indicate that the culture of SiHa cells in SFCM in the presence of fibronectin perhaps generates a signalling cascade which leads to the expression of pro-MMP-9 and the activation of MMP-2 within 2 h. The signalling pathways activated seem to be the FAK/ERK/PI-3K pathway.
Mitra
Aparna
A
Department of Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, 37 S.P. Mukherjee Road, Kolkata, 700 026, India.
Chakrabarti
Jayati
J
Banerji
Aniruddha
A
Das
Shamik
S
Chatterjee
Amitava
A
D015153:Blotting, Western; D002448:Cell Adhesion; D016895:Culture Media, Serum-Free; D004789:Enzyme Activation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005260:Female; D005353:Fibronectins / Q000378:metabolism*; D051417:Focal Adhesion Kinase 1 / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D014407:Tumor Cells, Cultured; D002583:Uterine Cervical Neoplasms / Q000201:enzymology / Q000378:metabolism*
D016895:Culture Media, Serum-Free; D005353:Fibronectins; D019869:Phosphatidylinositol 3-Kinases; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; D048049:Extracellular Signal-Regulated MAP Kinases; D020778:Matrix Metalloproteinase 2