title: Insulin-like growth factor and epidermal growth factor signaling in breast cancer cell growth: focus on endocrine resistant disease.
abstract: Breast cancer is the most common type of cancer for women worldwide with a lifetime risk amounting to a staggering total of 10%. It is well established that the endogenous synthesis of insulin-like growth factor (IGF) and epidermal growth factor (EGF) polypeptide growth factors are closely correlated to malignant transformation and all the steps of the breast cancer metastatic cascade. Numerous studies have demonstrated that both estrogens and growth factors stimulate the proliferation of steroid-dependent tumor cells, and that the interaction between these signaling pathways occurs at several levels. Importantly, the majority of breast cancer cases are estrogen receptor- (ER-) positive which have a more favorable prognosis and pattern of recurrence with endocrine therapy being the backbone of treatment. Unfortunately, the majority of patients progress to endocrine therapy resistant disease (acquired resistance) whereas a proportion of patients may fail to respond to initial therapy (de novo resistance). The IGF-I and EGF downstream signaling pathways are closely involved in the process of progression to therapy resistant disease. Modifications in the bioavailability of these growth factors contribute critically to disease progression. In the present review therefore, we will discuss in depth how IGF and EGF signaling participate in breast cancer pathogenesis and progression to endocrine resistant disease.
authors.affiliation: Laboratory of Anatomy-Histology-Embryology, School of Medicine, University of Crete, 71003 Heraklion, Greece.
authors.forename: Kallirroi
authors.initials: K
authors.lastname: Voudouri
authors.affiliation: Laboratory of Anatomy-Histology-Embryology, School of Medicine, University of Crete, 71003 Heraklion, Greece.
authors.forename: Aikaterini
authors.initials: A
authors.lastname: Berdiaki
authors.affiliation: Laboratory of Pathology, School of Medicine, University of Crete, 71003 Heraklion, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Tzardi
authors.affiliation: Laboratory of Anatomy-Histology-Embryology, School of Medicine, University of Crete, 71003 Heraklion, Greece.
authors.forename: George N
authors.initials: GN
authors.lastname: Tzanakakis
authors.affiliation: Laboratory of Anatomy-Histology-Embryology, School of Medicine, University of Crete, 71003 Heraklion, Greece.
authors.forename: Dragana
authors.initials: D
authors.lastname: Nikitovic
mesh_terms: D001682:Biological Availability; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D066255:EGF Family of Proteins / Q000378:metabolism*; D004703:Endocrine System / Q000473:pathology*; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D066255:EGF Family of Proteins; D007334:Insulin-Like Growth Factor I