RESUMEN

CCN1, a secreted matrix-associated molecule, is involved in multiple cellular processes. Accumulating evidence supports that CCN1 plays an important role in tumorigenesis and progression of breast cancer. In this study, we have developed a novel CCN1 function-blocking monoclonal antibody (mAb), designated YM1B. YM1B binds to human CCN1 with high specificity, recognizing the native CCN1 structure with undisturbed disulfide linkages. Our analyses have mapped the YM1B recognition region to domain IV of CCN1, likely in proximity to the DM site. In breast cancer cells, CCN1 can induce actin reorganization, formation of lamellipodia, and cell migration/invasion through the αV integrins/Rac1/ERK signaling axis; these CCN1-dependent activities can be effectively suppressed by YM1B. Our results also suggest that YM1B may exert its CCN1-blocking effect by perturbing the interaction of CCN1 with vitronectin and fibronectin, which are ligands of αV integrins and instrumental for integrin activation. This CCN1-specific mAb may open a new potential avenue for therapeutic intervention of breast cancer progression.

Asunto(s)

Anticuerpos Monoclonales/farmacología , Movimiento Celular/efectos de los fármacos , Proteína 61 Rica en Cisteína/antagonistas & inhibidores , Citoesqueleto/efectos de los fármacos , Proteína de Unión al GTP rac1/metabolismo , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/metabolismo , Especificidad de Anticuerpos/inmunología , Sitios de Unión de Anticuerpos , Western Blotting , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proteína 61 Rica en Cisteína/inmunología , Proteína 61 Rica en Cisteína/metabolismo , Citoesqueleto/metabolismo , Epítopos/inmunología , Epítopos/metabolismo , Femenino , Fibronectinas/metabolismo , Humanos , Integrina alfaV/metabolismo , Células MCF-7 , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Unión Proteica/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Vitronectina/metabolismo