RESUMO
Transforming growth factor-beta1 (TGF-beta1) plays an essential role in tumor progression and metastasis. Integrins are the major adhesive molecules in mammalian cells. Here we found that TGF-beta1 increased the migration and cell surface expression of alphavbeta3 integrin in human chondrosarcoma cells (JJ012 cells). Phosphatidylinositol 3-kinase inhibitor (PI3K; Ly294002) or Akt inhibitor inhibited the TGF-beta1-induced increase the migration of chondrosarcoma cells. TGF-beta1 stimulation increased the phosphorylation of p85 subunit of PI3K, and serine 473 of Akt. In addition, treatment of JJ102 cells with NF-kappaB inhibitor (PDTC) or IkappaB protease inhibitor (TPCK) inhibited TGF-beta1-induced cells migration and integrins expression. Treatment of JJ012 cells with TGF-beta1-induced IkappaB kinase alpha/beta (IKKalpha/beta) phosphorylation, IkappaBalpha phosphorylation, p65 Ser(536) phosphorylation, and kappaB-luciferase activity. The TGF-beta1-mediated increases in IKKalpha/beta phosphorylation and p65 Ser(536) phosphorylation were inhibited by Ly294002 and Akt inhibitor. Cotransfection with p85 and Akt mutants also reduced the TGF-beta1-induced kappaB-luciferase activity. Taken together, these results suggest that the TGF-beta1 acts through PI3K/Akt, which in turn activates IKKalpha/beta and NF-kappaB, resulting in the activations of alphavbeta3 integrins and contributing the migration of chondrosarcoma cells.
Assuntos
Movimento Celular/efeitos dos fármacos , Condrossarcoma/metabolismo , Integrina alfaVbeta3/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Linhagem Celular Tumoral , Condrossarcoma/patologia , Humanos , Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição RelA/metabolismo , Regulação para CimaRESUMO
Bone metastases are common complications of breast cancer. Integrins are the major adhesive molecules in mammalian cells. Here we found that osteoblast conditioned medium (OBCM) increased the migration and cell surface expression of beta1 or beta3 integrin in human breast cancer cells (MDA-MB-231 cells). beta1 or beta3 integrin monoclonal antibodies (mAbs) or small interference RNA (siRNA) against beta1 or beta3 integrin inhibited the OBCM-induced increase in the migration of breast cancer cells. Transforming growth factor-beta1 (TGF-beta1) siRNA could remarkably blocked OBCM-induced chemomigration and beta1 and beta3 integrin expression in breast cancer cells. Stimulation of cells with OBCM caused an increase in Akt and extracellular signal-regulated kinase (ERK) phosphorylation in a time-dependent manner. In addition, treatment of MDA-MB-231 cells with phosphatidylinositol 3-kinase inhibitor (LY294002), ERK inhibitor (PD98059), NF-kappaB inhibitor (PDTC), or IkappaB protease inhibitor (TPCK) inhibited OBCM-induced cells migration and integrins expression. Treatment of MDA-MB-231 cells with OBCM induced IkappaB kinase alpha/beta (IKK alpha/beta) phosphorylation, IkappaBalpha phosphorylation, IkappaBalpha degradation, p65 Ser(536) phosphorylation, and kappaB-luciferase activity. The OBCM-mediated increases in IKK alpha/beta phosphorylation, p65 Ser(536) phosphorylation, and kappaB-luciferase activity were inhibited by LY294002 and PD98059. In addition, TGF-beta1 siRNA also reduced the OBCM-induced ERK, Akt, IKKalpha/beta, IkappaBalpha, and p65 phosphorylation. Taken together, these results suggest that the osteoblast-derived TGF-beta1 acts through Akt and ERK, which in turn activates IKKalpha/beta and NF-kappaB, resulting in the activations of beta1 and beta3 integrins and contributing the migration of breast cancer cell.
Assuntos
Neoplasias da Mama/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Integrina beta1/metabolismo , Integrina beta3/metabolismo , NF-kappa B/metabolismo , Osteoblastos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Western Blotting , Neoplasias da Mama/patologia , Movimento Celular , Meios de Cultivo Condicionados/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Citometria de Fluxo , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Luciferases/metabolismo , Camundongos , Inibidor de NF-kappaB alfa , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , Fosforilação , Transdução de Sinais , Transfecção , Células Tumorais Cultivadas , Regulação para CimaRESUMO
The chemokine stromal-derived factor-1alpha (SDF-1alpha) and its receptor, CXCR4, play a crucial role in adhesion and migration of human cancer cells. Integrins are the major adhesive molecules in mammalian cells. Here we found that SDF-1alpha increased the migration and cell surface expression of beta1 or beta3 integrin in human lung cancer cells (A549 cells). CXCR4-neutralizing antibody, CXCR4 specific inhibitor (AMD3100) or small interfering RNA against CXCR4 inhibited the SDF-1alpha-induced increase in the migration of lung cancer cells. Stimulation of cells with SDF-1alpha caused an increase in extracellular signal regulated kinase (ERK) phosphorylation in a time-dependent manner. In addition, treatment of A549 cells with ERK inhibitor (PD98059), NF-kappaB inhibitor (PDTC) or IkappaB protease inhibitor (TPCK) inhibited SDF-1alpha-induced cells migration and integrins expression. Treatment of A549 cells with SDF-1alpha induced IkappaB kinase alpha/beta (IKK alpha/beta) phosphorylation, IkappaBalpha phosphorylation, IkappaBalpha degradation, p65 Ser(536) phosphorylation, and kappaB-luciferase activity. The SDF-1alpha-mediated increases in IKK alpha/beta phosphorylation, p65 Ser(536) phosphorylation, and kappaB-luciferase activity were inhibited by PD98059 and ERK2 mutant. Taken together, these results suggest that SDF-1alpha acts through CXCR4 to activate ERK, which in turn activates IKKalpha/beta and NF-kappaB, resulting in the activations of beta1 and beta3 integrins and contributing the migration of lung cancer cell.