Membrane-Bound Complement Regulatory Proteins in Breast Cancer: Are They Best Therapeutic Targets?

*Sofia Álvarez-Lorenzo, Rebeca Elizabeth Montalvo-Castro, Jeannie Jiménez-López, María Adriana Medina-Mondragón and Nohemí Salinas-Jazmín*

### **Abstract**

Breast cancer is one of the most aggressive diseases in women, responsible for thousands of deaths annually and millions of new diagnoses; its treatment presents multiple obstacles due to late diagnosis and the various mechanisms of tumor resistance. In breast cancer the membrane-bound complement regulatory proteins (mCRP) have been proposed as biomarkers of malignant cellular transformation. These are molecules capable of inhibiting therapeutic efficacy, from both antibodies and cytotoxic drugs. Therefore, these proteins are potential targets to increase therapeutic efficacy and avoid cancer progression. We will gather information about mCRP: (i) structural features; (ii) expression levels in breast cancer and relationship with prognosis; (iii) therapeutic resistance mechanisms; and (iv) strategies to down-regulate mCRP in both activity and expression.

**Keywords:** breast cancer, mCRP, therapeutic resistance, therapeutic mAb, systemic treatments
