Angiogenesis in prolactinomas: regulation and relationship with tumour behaviour.
Tumours are dependent on angiogenesis for growth and inhibition of angiogenesis has become a target for antineoplastic therapy. In the pituitary, unlike other tissues, vascularization is lower in adenomas compared to the normal gland. Despite this finding, a relationship between increased vascularity and several aspects of prolactinoma behaviour such as size, invasiveness, surgical outcome and malignancy, has been demonstrated. The process of angiogenesis is the result of a balance of stimulating and inhibiting factors. It is likely that an interaction between gene expression (such as pituitary tumour transforming gene (PTTG) and a novel gene located within the Edpm5 quantitative trait locus), hormonal stimuli including oestrogens, dopamine, 16 kDa fragments of prolactin and proangiogenic and antiangiogenic growth factors (for example, vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF-2), determine the final angiogenic phenotype of prolactinomas, and thus subsequent tumour behaviour. The elucidation of all the factors involved in the regulation of angiogenesis and their interactions might open new possibilities in the treatment of prolactinomas, especially in those cases with resistance or intolerance to dopamine agonists.
de la Torre
N Garcia
NG
Servicio de Endocrinología, Hospital Clínico San Carlos, Profesor Martín Lagos s/n, 28040, Madrid, Spain.
Turner
H E
HE
Wass
J A H
JA
D004298:Dopamine / Q000235:genetics / Q000502:physiology; D018491:Dopamine Agonists / Q000627:therapeutic use; D019008:Drug Resistance, Neoplasm; D004967:Estrogens / Q000235:genetics / Q000502:physiology; D016222:Fibroblast Growth Factor 2 / Q000235:genetics / Q000502:physiology; D015972:Gene Expression Regulation, Neoplastic; D052138:Genes, Neoplasm; D006801:Humans; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000235:genetics / Q000502:physiology; D009389:Neovascularization, Pathologic / Q000235:genetics; D010911:Pituitary Neoplasms / Q000098:blood supply* / Q000235:genetics / Q000503:physiopathology*; D011388:Prolactin / Q000235:genetics / Q000502:physiology; D015175:Prolactinoma / Q000098:blood supply* / Q000235:genetics / Q000503:physiopathology*; D064249:Securin; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000502:physiology
D018491:Dopamine Agonists; D004967:Estrogens; D009363:Neoplasm Proteins; D064249:Securin; D042461:Vascular Endothelial Growth Factor A; C578002:pituitary tumor-transforming protein 1, human; D016222:Fibroblast Growth Factor 2; D011388:Prolactin; D004298:Dopamine