endothelin-1 and Carcinoma--Ductal--Breast

Deregulation of the endothelin system, comprised of endothelin-1 (ET-1), its isoforms (ET-2 and ET-3) and their receptors (ET(A)R and ET(B)R), is under investigation in various types of human cancer. ET-1 has been suggested to participate in breast cancer development and progression, while Big ET-1, its biological precursor, has also been found elevated in breast cancer patients. In the present study, we investigated plasma ET-1 and Big ET-1 levels in patients with suspicious mammographic lesions, in order to assess their potential application as diagnostic biomarkers in the early estimation of breast disease. The study consisted of 94 patients (Group A to 30 patients with invasive ductal carcinoma: Group B, 30 with ductal carcinoma in situ; and group C, 34 with papilloma or ductal hyperplasia), who underwent an image-guided vacuum-assisted breast biopsy, and 30 healthy controls (group D). ET-1 and Big ET-1 plasma levels were measured with enzyme-linked immunosorbent assay. ET-1 levels did not exhibit significant differences between patients and healthy controls (Group A to 0.92 fmol/mL; Group B: 0.90 fmol/mL; Group C: 0.66 fmol/mL; and Group D: 0.86 fmol/mL). In contrast, Big ET-1 levels were significantly higher in patients with invasive or in situ carcinoma compared to healthy controls (Group A: 0.69 fmol/mL; Group B, 0.62 fmol/mL; and group D: 0.39 fmol/mL; p < 0.001 and p < 0.01). Plasma Big ET-1 may provide a useful tool for the early detection of invasive or noninvasive ductal breast cancer. The utilization of such a diagnostic tool would greatly assist in the modern management of breast cancer.

Topics: Adult; Aged; Biomarkers, Tumor; Breast Neoplasms; Carcinoma, Ductal, Breast; Carcinoma, Intraductal, Noninfiltrating; Early Detection of Cancer; Endothelin-1; Enzyme-Linked Immunosorbent Assay; Female; Humans; Middle Aged; Prognosis; Protein Precursors; Sensitivity and Specificity

The objective of this study was to investigate expression of various growth factors associated with angiogenesis and lymphangiogenesis and of their receptors in ductal carcinomas in situ of the breast (DCIS). We studied protein expression of basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF)-A, endothelin (ET)-1, and VEGF-C, and their receptors bFGF-R1, Flt-1, KDR, ET(A)R, ET(B)R, and Flt-4 immunohistochemically in 200 DCIS (pure DCIS: n=96; DCIS adjacent to an invasive component: n=104) using self-constructed tissue microarrays. Basic fibroblast growth factor-R1, VEGF-C, Flt-4, and ET(A)R were expressed in the tumour cells in the majority of cases, whereas bFGF and Flt-1 expression was rarely observed. VEGF-A, KDR, ET-1, and ET(B)R were variably expressed. The findings of VEGF-C and its receptor Flt-4 as lymphangiogenic factors being expressed in tumour cells of nearly all DCIS lesions and the observed expression of various angiogenic growth factors in most DCIS suggest that in situ carcinomas are capable of inducing angiogenesis and lymphangiogenesis. Moreover, we found a higher angiogenic activity in pure DCIS as compared to DCIS with concomitant invasive carcinoma. This association of angiogenic factors with pure DCIS was considerably more pronounced in the subgroup of non-high-grade DCIS (n=103) as compared with high-grade DCIS (n=94). Determination of these angiogenic markers may therefore facilitate discrimination between biologically different subgroups of DCIS and could help to identify a particularly angiogenic subset with a potentially higher probability of recurrence or of progression to invasiveness. For these DCIS, targeting angiogenesis may represent a feasible therapeutic approach for prevention of progression of DCIS to invasion.

Topics: Adolescent; Adult; Aged; Biomarkers; Breast Neoplasms; Carcinoma in Situ; Carcinoma, Ductal, Breast; Endothelin-1; Female; Fibroblast Growth Factor 2; Humans; Middle Aged; Protein Array Analysis; Receptor Protein-Tyrosine Kinases; Receptor, Fibroblast Growth Factor, Type 1; Receptors, Fibroblast Growth Factor; Receptors, Vascular Endothelial Growth Factor; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factor C; Vascular Endothelial Growth Factor Receptor-1; Vascular Endothelial Growth Factor Receptor-2

Endothelins (ET-1, ET-2 and ET-3) are 21-amino acid vasoactive peptides that bind to G-protein-linked transmembrane receptors, ET-RA and ET-RB. As well as modulating vasoconstriction, endothelins regulate growth in several cell types and may also affect differentiation, inflammation and angiogenesis. Both macrophages and endothelins are found in areas of hypoxia in solid tumors and ET-2 expression may be modulated by hypoxia in some tumors. As the peptide structure of mature endothelins is similar to that of CXC chemokines, we asked if endothelins contribute to control of macrophage distribution in tumors. We found that ET-2 is a chemoattractant for macrophages and THP-1 monocytic cells, but not for freshly isolated monocytes. The chemotactic response to ET-2 shows a typical bell-shaped response curve. Experiments with endothelin receptor antagonists showed that migration to ET-2 is mediated via the ET-RB receptor. Moreover, monocytes do not express ET-RB. Chemotaxis towards ET-2 is via the MAPK pathway: p44 and p42 are phosphorylated when THP-1 cells are stimulated with ET-2, and the MAPKK inhibitor PD98059 stops chemotaxis. As with 'classical' chemokines, migration toET-2 is also inhibited by hypoxia and by pertussis toxin. As well as its chemotactic properties, ET-2 leads to activation of macrophages. In human breast tumors that express ET-2, endothelins and ET-RB expressing macrophages often co-localized. While shorter than 'classical' chemokines, ET-2 shares a similar peptide sequence with chemokines and may signal via a similar receptor and MAPK-mediated pathway. Furthermore, ET-2 expression by tumors may modulate the behavior of macrophages such that activated cells accumulate in areas of hypoxia.

Topics: Bacterial Proteins; Breast Neoplasms; Carcinoma, Ductal, Breast; Cell Hypoxia; Cell Line; Chemokines, CXC; Chemotactic Factors; Chemotaxis; Endothelin Receptor Antagonists; Endothelin-1; Endothelin-2; Enzyme Inhibitors; Female; Flavonoids; Humans; Macrophage Activation; Macrophages; MAP Kinase Signaling System; Membrane Proteins; Monocytes; Neoplasm Proteins; Oligopeptides; Peptides, Cyclic; Phosphorylation; Piperidines; Protein Processing, Post-Translational; Receptor, Endothelin A; Receptor, Endothelin B; Receptors, Endothelin; Structure-Activity Relationship

Endothelins (ETs) are peptides expressed in many tumours which may stimulate angiogenesis and desmoplasia. Because ETs have not been extensively studied mammary neoplasia, we assessed ET protein and mRNA expression and receptor mRNA expression in normal and neoplastic breast tissues.. Tissues from five normal breasts, six fibroadenomas, seven ductal carcinomas in situ (DCIS) and 25 invasive carcinomas were stained with anti-ET-1 and anti-ET-3 antibodies and analysed using a grading system. ET-1, ET-3, ETA and ETB mRNA expression was assessed by quantitative RT-PCR from eight carcinomas and five normals. Weak staining for ET-1 and ET-3 was detected in all normals. Moderate to strong staining was seen in 72% and 64% of carcinomas for ET-1 and ET-3, respectively. Most fibroadenomas showed weak positivity for ET-1 (83%) and ET-3 (67%). ET-1 and ET-3 mRNA levels were upregulated in carcinomas compared with normal breast. No ETA mRNA was not detected in any tissue. ETB mRNA was detected in normal breast and was increased in carcinomas.. These results suggest that the ET system is altered in breast carcinomas and this may be of importance in the progression from in-situ to invasive carcinoma.

Topics: Blotting, Southern; Breast; Breast Neoplasms; Carcinoma in Situ; Carcinoma, Ductal, Breast; Endothelin-1; Endothelin-3; Female; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; Receptor, Endothelin B; Receptors, Endothelin; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger