Breast tumour angiogenesis

Effects of iron deficiency and iron overload on angiogenesis and oxidative stress-a potential dual role for iron in breast cancer

Estrogen alone cannot explain the differences in breast cancer (BC) recurrence and incidence rates in pre- and postmenopausal women. In this study, we have tested a hypothesis that, in addition to estrogen, both iron deficiency due to menstruation and iron accumulation as a result of menstrual stop play important roles in menopause-related BC outcomes. We first tested this hypothesis in cell culture models mimicking the high-estrogen and low-iron premenopausal condition or the low-estrogen and high-iron postmenopausal condition. Subsequently, we examined this hypothesis in mice that were fed iron-deficient and iron-overloaded diets. We show that estrogen only slightly up-regulates vascular endothelial growth factor (VEGF), an angiogenic factor known to be important in BC recurrence. It is, rather, iron deficiency that significantly promotes VEGF by stabilizing hypoxia-inducible factor-1α. Conversely, high iron levels increase oxidative stress and sustain mitogen-activated protein kinase activation, which are mechanisms of known significance in BC development. Taken together, our results suggest, for the first time, that an iron-deficiency-mediated proangiogenic environment could contribute to the high recurrence of BC in young patients, and iron-accumulation-associated pro-oxidant conditions could lead to the high incidence of BC in older women.

ATF3, an adaptive-response gene, enhances TGF{beta} signaling and cancer-initiating cell features in breast cancer cells

The activating transcription factor 3 (ATF3) gene is induced by a variety of signals, including many of those encountered by cancer cells. We present evidence that ATF3 is induced by TGFβ in the MCF10CA1a breast cancer cells and plays an integral role for TGFβ to upregulate its target genes snail, slug and twist, and to enhance cell motility. Furthermore, ATF3 upregulates the expression of the TGFb gene itself, forming a positive-feedback loop for TGFβ signaling. Functionally, ectopic expression of ATF3 leads to morphological changes and alterations of markers consistent with epithelial-to-mesenchymal transition (EMT). It also leads to features associated with breast-cancer-initiating cells: increased CD24(low)-CD44(high) population of cells, mammosphere formation and tumorigenesis. Conversely, knockdown of ATF3 reduces EMT, CD24(low)-CD44(high) cells and mammosphere formation. Importantly, knocking down twist, a downstream target, reduces the ability of ATF3 to enhance mammosphere formation, indicating the functional significance of twist in ATF3 action. To our knowledge, this is the first report demonstrating the ability of ATF3 to enhance breast cancer-initiating cell features and to feedback on TGFβ. Because ATF3 is an adaptive-response gene and is induced by various stromal signals, these findings have significant implications for how the tumor microenvironment might affect cancer development.

Comparative biomarker expression and RNA integrity in biospecimens derived from radical retropubic and robot-assisted laparoscopic prostatectomies

BACKGROUND

Knowledge of preanalytic conditions that biospecimens are subjected to is critically important because novel surgical procedures, tissue sampling, handling, and storage might affect biomarker expression or invalidate tissue samples as analytes for some technologies.

METHODS

We investigated differences in RNA quality, gene expression by quantitative real-time PCR, and immunoreactive protein expression of selected prostate cancer biomarkers between tissues from retropubic radical prostatectomy (RRP) and robot-assisted laparoscopic prostatectomy (RALP). Sections of tissue microarray of 23 RALP and 22 RRP samples were stained with antibodies to androgen receptor (AR) and prostate-specific antigen (PSA) as intersite controls, and 14 other candidate biomarkers of research interest to three laboratories within the Australian Prostate Cancer BioResource tissue banking network. Quantitative real-time PCR was done for AR, PSA (KLK3), KLK2, KLK4, and HIF1A on RNA extracted from five RALP and five RRP frozen tissue cores.

RESULTS

No histologic differences were observed between RALP and RRP tissue. Biomarker staining grouped these samples into those with increased (PSA, CK8/18, CKHMW, KLK4), decreased (KLK2, KLK14), or no change in expression (AR, ghrelin, Ki67, PCNA, VEGF-C, PAR2, YB1, p63, versican, and chondroitin 0-sulfate) in RALP compared with RRP tissue. No difference in RNA quality or gene expression was detected between RALP and RRP tissue.

CONCLUSIONS

Changes in biomarker expression between RALP and RRP tissue exist at the immunoreactive protein level, but the etiology is unclear.

IMPACT

Future studies should account for changes in biomarker expression when using RALP tissues, and mixed cohorts of RALP and RRP tissue should be avoided.

Immunohistochemical expression of vascular endothelial growth factor and vascular endothelial growth factor receptor-2 in canine simple mammary gland adenocarcinomas

The expression of 5 markers associated with angiogenesis, proliferation, and apoptosis was studied in 26 canine simple mammary gland adenocarcinomas (SMGAs). The adenocarcinomas were graded histologically, and tissue sections were immunohistochemically stained for the expression of vascular endothelial growth factor (VEGF), VEGF receptor-2 (VEGFR-2), intra-tumor microvessel density, and tumor proliferation (PI) using antibodies against VEGF, VEGFR-2, von Willebrand factor, and Ki-67 antigen, respectively. Apoptotic indices (AI) were determined by an apoptosis assay. Markers VEGF and VEGFR-2 were detected in 96% and 100% of SMGAs, respectively. A high correlation between histologic grade and PI (r = 0.73), a moderate correlation between VEGF and histologic grade (r = 0.33), and between VEGF and PI (r = 0.42) were found. There was a significant difference in median PI among the 3 histologic grade groups (r < 0.05). Vascular endothelial growth factor may stimulate tumor cell proliferation through an autocrine loop, since VEGF and VEGFR-2 were expressed in most tumors.

DNA methylation analysis of the HIF-1α prolyl hydroxylase domain genes PHD1, PHD2, PHD3 and the factor inhibiting HIF gene FIH in invasive breast carcinomas

AIMS

Hypoxia-inducible factor-1 (HIF-1) activity is regulated by prolyl hydroxylase (PHD1, PHD2, PHD3) and factor inhibiting HIF-1 (FIH) that target the α subunit of HIF-1 (HIF-1α) for proteosomal degradation. We hypothesised that the elevated HIF-1α level is due in some tumours to epigenetic silencing by DNA hypermethylation of the promoter region of one or more of the PHDs and FIH genes. The aims were to define the presence or absence of promoter methylation of PHDs and FIH in cell lines of various sources and breast carcinomas and, if present, determine its effect on mRNA and protein expression.

METHODS AND RESULTS

Tumour cell lines (n = 20) and primary invasive breast carcinomas (n = 168) were examined for promoter region DNA methylation using methylation-sensitive high-resolution melting. There was evidence of PHD3 but not of PHD1, PHD2 or FIH DNA methylation in breast cancer (SkBr3) and leukaemic (HL60 and CCRF-CEM) cell lines, but there was no evidence of methylation in any of 168 breast cancers. Only the high-level PHD3 methylation seen in leukaemic cell lines correlated with absent mRNA and protein expression.

CONCLUSIONS

Methylation-induced epigenetic silencing of PHD1, PHD2, PHD3 and FIH is unlikely to underlie up-regulated HIF-1α expression in human breast cancer but may play a role in other tumour types.

Vascular endothelial growth factor in the serum of breast cancer patients

Here we present the results of comparative immunoenzyme assay of the initial serum levels of VEGF in breast cancer patients (stages T1N0M0 and T2N0M0) and apparently healthy women (controls). It was found that VEGF concentrations in the serum of patients with breast cancer stages T1N0M0 and T2N0M0 significantly surpassed the control levels. Increased levels of VEGF surpassing the threshold values were more often observed in patients with T2N0M0 breast cancer compared to patients with T1N0M0 tumor. At the same time, this marker cannot be used in the diagnostics of this disease because in only 21.4% patients serum level of VEGF surpassed the upper boundary for this growth factor observed in the serum of control women. Serum concentration of VEGF in patients with stages T1N0M0 and T2N0M0 breast cancer did not depend on patient's age and reproductive function and receptor status of the primary tumor (estrogen and progesterone receptors), but was closely associated with tumor histogenesis and differentiation degree. Significantly higher levels of VEGF were observed in patients with lobular infiltrative breast carcinoma compared to patients with ductal tumors and in patients with low-differentiated tumors compared to highly and moderately differentiated tumors. High initial concentrations of VEGF (>300 pg/ml) were more often detected in patients with T2N0M0 breast cancer developing relapses within the first 3 years of follow-up compared to patients without relapses during the corresponding period (p=0.001). These findings suggest that serum level of VEGF in patients with T2N0M0 breast cancer before treatment can be used as an additional marker in parallel with standard clinical and morphological signs of the disease for more precise prognosis of early relapse (during the first 3 years of follow-up).

Evaluation of morphine effect on tumour angiogenesis in mouse breast tumour model, EATC

Breast cancer is the leading cause of death among women, and morphine is used to relieve the pain of patients with cancer. The data on the effects of morphine on tumour growth and angiogenesis are contradictory. We determined in mouse breast cancer model whether analgesic doses of morphine would affect tumour angiogenesis, and then the correlation between microvessel density (MVD), Doppler sonography (DS) and 99mTc-Tetrofosmin (TF) uptake. Ehrlich ascites tumour cell xenografts, Pgp-negative tumour were divided into two groups: (a) Morphine sulphate [0.714 mg/kg/day (equivalent to 50 mg per day for a 70 kg human)], (b) no-morphine. For the determination of angiogenesis in mice tumour tissue, TF scintigraphy, microvessel density and DS were done. MVD was significantly different between groups (49.4±1.8 vs. 41.8±1.9, morphine and no-morphine groups, respectively, P<0.001). A strong correlation was found between late uptakes of mass at scintigraphy and degree of angiogenesis in histopathologic examination (r=0.52, P<0.01). There was statistically significant inverse correlation between degree of angiogenesis in histopathologic examination and washout ratio of TF (r=0.40, P<0.05). The higher values for angiogenesis are related to higher TF reuptake. There was no statistically significant correlation between DS and TF. A strong correlation was found between MVD and grade of DS (r=0.51, P<0.01). Our preclinical mice study indicates that morphine at clinically relevant doses stimulates angiogenesis, and angiogenesis triggered of morphine is demonstrated with MVD and DS, but not TF. However, uptake and washout of TF are compared with immunohistochemically assessed morphine-stimulated angiogenesis in tumour tissue.

Vascular Robo4 restricts proangiogenic VEGF signaling in breast

Formation of the vascular system within organs requires the balanced action of numerous positive and negative factors secreted by stromal and epithelial cells. Here, we used a genetic approach to determine the role of SLITs in regulating the growth and organization of blood vessels in the mammary gland. We demonstrate that vascularization of the gland is not affected by loss of Slit expression in the epithelial compartment. Instead, we identify a stromal source of SLIT, mural cells encircling blood vessels, and show that loss of Slit in the stroma leads to elevated blood vessel density and complexity. We examine candidate SLIT receptors, Robo1 and Robo4, and find that increased vessel angiogenesis is phenocopied by loss of endothelial-specific Robo4, as long as it is combined with the presence of an angiogenic stimulus such as preneoplasia or pregnancy. In contrast, loss of Robo1 does not affect blood vessel growth. The enhanced growth of blood vessels in Robo4(-/-) endothelium is due to activation of vascular endothelial growth factor (VEGF)-R2 signaling through the Src and FAK kinases. Thus, our studies present a genetic dissection of SLIT/ROBO signaling during organ development. We identify a stromal, rather than epithelial, source of SLITs that inhibits blood vessel growth by signaling through endothelial ROBO4 to down-regulate VEGF/VEGFR2 signaling.

Vascular endothelial growth factor receptor-2 in breast cancer

Investigations over the last decade have established the essential role of growth factors and their receptors during angiogenesis and carcinogenesis. The vascular endothelial growth factor receptor (VEGFR) family in mammals contains three members, VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1) and VEGFR-3 (Flt-4), which are transmembrane tyrosine kinase receptors that regulate the formation of blood and lymphatic vessels. In the early 1990s, the above VEGFR was structurally characterized by cDNA cloning. Among these three receptors, VEGFR-2 is generally recognized to have a principal role in mediating VEGF-induced responses. VEGFR-2 is considered as the earliest marker for endothelial cell development. Importantly, VEGFR-2 directly regulates tumor angiogenesis. Therefore, several inhibitors of VEGFR-2 have been developed and many of them are now in clinical trials. In addition to targeting endothelial cells, the VEGF/VEGFR-2 system works as an essential autocrine/paracrine process for cancer cell proliferation and survival. Recent studies mark the continuous and increased interest in this related, but distinct, function of VEGF/VEGFR-2 in cancer cells: the autocrine/paracrine loop. Several mechanisms regulate VEGFR-2 levels and modulate its role in tumor angiogenesis and physiologic functions, i.e.: cellular localization/trafficking, regulation of cis-elements of promoter, epigenetic regulation and signaling from Notch, cytokines/growth factors and estrogen, etc. In this review, we will focus on updated information regarding VEGFR-2 research with respect to the molecular mechanisms of VEGFR-2 regulation in human breast cancer. Investigations in the activation, function, and regulation of VEGFR-2 in breast cancer will allow the development of new pharmacological strategies aimed at directly targeting cancer cell proliferation and survival.

Vasohibin-1 as a potential predictor of aggressive behavior of ductal carcinoma in situ of the breast

Vasohibin-1 is a recently identified negative feedback regulator of angiogenesis induced by VEGF-A and bFGF. In this study, we first evaluated mRNA expression of vasohibin-1 and CD31 in 39 Japanese female breast carcinoma specimens including 22 invasive ductal carcinoma (IDC) and 17 ductal carcinoma in situ (DCIS) using a real-time quantitative RT-PCR (QRT-PCR) with LightCycler system. In addition, we also immunolocalized vasohibin-1 and CD31 and compared their immunoreactivity to nuclear grades and histological grades of 100 carcinoma cases (50 IDC and 50 DCIS). There were no statistically significant differences of CD31 mRNA expression and the number of CD31 positive vessels between DCIS and IDC (P = 0.250 and P = 0.191, respectively), whereas there was a statistically significant difference in vasohibin-1 mRNA expression and the number of vasohibin-1 positive vessels in DCIS and IDC (P = 0.022 and P < or = 0.001, respectively). There was a significant positive correlation between vasohibin-1 mRNA level and Ki-67 labeling index in DCIS (r(2) = 0.293, P < or = 0.001). In addition, vasohibin-1 mRNA expression was correlated with high nuclear and histological grades in DCIS cases and a significant positive correlation was detected between the number of vasohibin-1 positive vessels and Ki-67 labeling index or nuclear grade or Van Nuys classification of carcinoma cells (P < or = 0.001, respectively). These results all indicate the possible correlation between aggressive biological features in DCIS including increased tumor cell proliferation and the status of neovascularization determined by vasohibin-1 immunoreactivity.

Large meta-analysis of multiple cancers reveals a common, compact and highly prognostic hypoxia metagene

Background:

There is a need to develop robust and clinically applicable gene expression signatures. Hypoxia is a key factor promoting solid tumour progression and resistance to therapy; a hypoxia signature has the potential to be not only prognostic but also to predict benefit from particular interventions.

Methods:

An approach for deriving signatures that combine knowledge of gene function and analysis of in vivo co-expression patterns was used to define a common hypoxia signature from three head and neck and five breast cancer studies. Previously validated hypoxia-regulated genes (seeds) were used to generate hypoxia co-expression cancer networks.

Results:

A common hypoxia signature, or metagene, was derived by selecting genes that were consistently co-expressed with the hypoxia seeds in multiple cancers. This was highly enriched for hypoxia-regulated pathways, and prognostic in multivariate analyses. Genes with the highest connectivity were also the most prognostic, and a reduced metagene consisting of a small number of top-ranked genes, including VEGFA, SLC2A1 and PGAM1, outperformed both a larger signature and reported signatures in independent data sets of head and neck, breast and lung cancers.

Conclusion:

Combined knowledge of multiple genes' function from in vitro experiments together with meta-analysis of multiple cancers can deliver compact and robust signatures suitable for clinical application.

Computer-aided Image Processing of Angiogenic Histological

This article reviews the questions regarding the image evaluation of angiogeneic histological samples, particularly the ovarian epithelial cancer. Review is focused on the principles of image analysis in the field of histology and pathology. The definition, classification, pathogenesis and angiogenesis regulation in the ovaries are also briefly discussed. It is hoped that the complex image analysis together with the patient's clinical parameters will allow an acquiring of a clear pathogenic picture of the disease, extension of the differential diagnosis and become a useful tool for the evaluation of drug effects. The challenge of the assessment of angiogenesis activity is the heterogeneity of several objects: parameters derived from patient's anamnesis as well as of pathology samples. The other unresolved problems are the subjectivity of the region of interest selection and performance of the whole slide scanning.

KEYWORDS

Angiogenesis; Image processing; Microvessel density; Cancer; Pathology.

A distinct microvascular pattern accompanied by aggressive clinical course in breast carcinomas: a fact or a coincidence?

The aim of this study was to evaluate the potential relationship of microvascular growth patterns with survival in invasive breast carcinomas. Thirty-one invasive ductal carcinoma cases, followed up at least for 38 months, constituted our series. All cases had been studied for ER/PR and HER2/neu expression. Clinicopathological and survival data were obtained from the archives. Tissue sections from all cases were stained with CD34 antibody to highlight the microvascular network and to measure microvessel density (MVD). The cases were then classified according to the dominance of one of the five recognizable microvascular patterns. Cox proportional hazard regression model, Fisher's exact test, and multivariate general linear model (GLM) were used to uncover the effects of the variables, such as nodal status, distant metastasis, angiogenic patterns, and MVD, on survival. There was an association between only one of the microvascular patterns and aggressive clinical course. Increased blood-filled capillaries with some clustering in the tumor might be a predictor of aggressive biological behavior in invasive breast carcinomas. Similar studies investigating larger series are needed before a generalized conclusion can be made.

No evidence for promoter region methylation of the succinate dehydrogenase and fumarate hydratase tumour suppressor genes in breast cancer

Background

Succinate dehydrogenase (SDH) and fumarate hydratase (FH) are tricarboxylic acid (TCA) cycle enzymes that are also known to act as tumour suppressor genes. Increased succinate or fumarate levels as a consequence of SDH and FH deficiency inhibit hypoxia inducible factor-1α (HIF-1α) prolyl hydroxylases leading to sustained HIF-1α expression in tumours. Since HIF-1α is frequently expressed in breast carcinomas, DNA methylation at the promoter regions of the SDHA, SDHB, SDHC and SDHD and FH genes was evaluated as a possible mechanism in silencing of SDH and FH expression in breast carcinomas.

Findings

No DNA methylation was identified in the promoter regions of the SDHA, SDHB, SDHC, SDHD and FH genes in 72 breast carcinomas and 10 breast cancer cell lines using methylation-sensitive high resolution melting which detects both homogeneous and heterogeneous methylation.

Conclusion

These results show that inactivation via DNA methylation of the promoter CpG islands of SDH and FH is unlikely to play a major role in sporadic breast carcinomas.

Tumor vascular permeability to a nanoprobe correlates to tumor-specific expression levels of angiogenic markers

Background

Vascular endothelial growth factor (VEGF) receptor-2 is the major mediator of the mitogenic, angiogenic, and vascular hyperpermeability effects of VEGF on breast tumors. Overexpression of VEGF and VEGF receptor-2 is associated with the degree of pathomorphosis of the tumor tissue and unfavorable prognosis. In this study, we demonstrate that non-invasive quantification of the degree of tumor vascular permeability to a nanoprobe correlates with the VEGF and its receptor levels and tumor growth.

Methodology/Principal Findings

We designed an imaging nanoprobe and a methodology to detect the intratumoral deposition of a 100 nm-scale nanoprobe using mammography allowing measurement of the tumor vascular permeability in a rat MAT B III breast tumor model. The tumor vascular permeability varied widely among the animals. Notably, the VEGF and VEGF receptor-2 gene expression of the tumors as measured by qRT-PCR displayed a strong correlation to the imaging-based measurements of vascular permeability to the 100 nm-scale nanoprobe. This is in good agreement with the fact that tumors with high angiogenic activity are expected to have more permeable blood vessels resulting in high intratumoral deposition of a nanoscale agent. In addition, we show that higher intratumoral deposition of the nanoprobe as imaged with mammography correlated to a faster tumor growth rate. This data suggest that vascular permeability scales to the tumor growth and that tumor vascular permeability can be a measure of underlying VEGF and VEGF receptor-2 expression in individual tumors.

Conclusions/Significance

This is the first demonstration, to our knowledge, that quantitative imaging of tumor vascular permeability to a nanoprobe represents a form of a surrogate, functional biomarker of underlying molecular markers of angiogenesis.

Angiogenesis in the progression of breast ductal proliferations

Angiogenesis, the formation of blood vessels, is necessary for a tumor to grow, but when angiogenesis first appears in the progression of breast ductal carcinomas is unknown. To determine when this occurs, the authors examined microvessel density (MVD) by CD31 and CD105 immunostaining in normal ducts, 32 cases of usual hyperplasia, 19 cases of atypical hyperplasia, and 29 cases of ductal carcinoma in situ (DCIS). Simple hyperplasia had a 22-fold greater MVD than normal ducts (P < .0001). An increase during the progression of ductal changes was highly significant (P < .0001). To determine a possible mechanism, immunohistochemistry for vascular endothelial growth factor (VEGF) was evaluated. VEGF staining intensity of ductal epithelium increased during the progression from normal to hyperplastic to DCIS. This study shows that the first significant increase in angiogenesis occurs very early in the evolution of ductal proliferations as ductal cells become hyperplastic.

Apoptosis-inducing high (.)NO concentrations are not sustained either in nascent or in developed cancers

Nitric oxide ((.)NO) induces apoptosis at high concentrations by S-nitrosating proteins such as glyceraldehyde-3-phosphate dehydrogenase. This literature analysis revealed that failure to sustain high (.)NO concentrations is common to all cancers. In cervical, gastric, colorectal, breast, and lung cancer, the cause of this failure is the inadequate expression of inducible nitric oxide synthase (iNOS), resulting from the inhibition of iNOS expression by TGF-beta1 at the mRNA level. In bladder, renal, and prostate cancer, the reason for the insufficient (.)NO levels is the depletion of arginine, resulting from arginase overexpression. Arginase competes with iNOS for arginine, catalyzing its hydrolysis to ornithine and urea. In gliomas and ovarian sarcomas, low (.)NO levels are caused by inhibition of iNOS by N-chlorotaurine, produced by infiltrating neutrophils. Stimulated neutrophils express myeloperoxidase, catalyzing H2O2 oxidation of Cl- to HOCl, which N-chlorinates taurine at its concentration of 19 mM in neutrophils. In squamous cell carcinomas of the skin, ovarian cancers, lymphomas, Hodgkin's disease, and breast cancers, low (.)NO concentrations arise from the inhibition of iNOS by N-bromotaurine, produced by eosinophil-peroxidase-expressing infiltrating eosinophils. Eosinophil peroxidase catalyzes the H2O2 oxidation of Br- to HOBr, which N-brominates taurine to N-bromotaurine at its concentration of 15 mM in eosinophils. In microvascularized tumors, the (.)NO concentration is further depleted; (.)NO is rapidly consumed by red blood cells (RBCs) through S-nitrosation of RBC glutathione and hemoglobin, and by oxidation to nitrate by RBC oxyhemoglobin. Angiogenesis-inhibiting antibodies are currently used to treat cancers; their mode of action is not, as previously thought, reduction of the tumor O2 or nutrient supply. They actually decrease the loss of (.)NO to RBCs.

Autocrine human growth hormone promotes tumor angiogenesis in mammary carcinoma

Accumulating literature implicates pathological angiogenesis and lymphangiogenesis as playing key roles in tumor progression. Autocrine human growth hormone (hGH) is a wild-type orthotopically expressed oncogene for the human mammary epithelial cell. Herein we demonstrate that autocrine hGH expression in the human mammary carcinoma cell line MCF-7 stimulated the survival, proliferation, migration, and invasion of a human microvascular endothelial cell line (HMEC-1). Autocrine/paracrine hGH secreted from mammary carcinoma cells also promoted HMEC-1 in vitro tube formation as a consequence of increased vascular endothelial growth factor-A (VEGF-A) expression. Semiquantitative RT-PCR analysis demonstrated that HMEC-1 cells express both hGH and the hGH receptor (hGHR). Functional antagonism of HMEC-1-derived hGH reduced HMEC-1 survival, proliferation, migration/invasion, and tube formation in vitro. Autocrine/paracrine hGH secreted by mammary carcinoma cells increased tumor blood and lymphatic microvessel density in a xenograft model of human mammary carcinoma. Autocrine hGH is therefore a potential master regulator of tumor neovascularization, coordinating two critical processes in mammary neoplastic progression, angiogenesis and lymphangiogenesis. Consideration of hGH antagonism to inhibit angiogenic processes in mammary carcinoma is therefore warranted.

Vasohibin-1 in human breast carcinoma: a potential negative feedback regulator of angiogenesis

Vasohibin-1 is a recently identified negative feedback inhibitor or suppressor of angiogenesis induced by vascular endothelial growth factor (VEGF)-A. The status of vasohibin-1 in human breast carcinoma has not been examined. We examined 151 breast specimens including 98 cases of invasive ductal carcinoma (IDC), 12 of ductal carcinoma in situ (DCIS), 16 of fibroadenoma (FA), six of inflammatory lesion, nine of fibrocystic change and seven of non-pathological breast tissue. We immunolocalized vasohibin-1 and compared its immunoreactivity to that of VEGF-A, basic fibroblastic growth factor (bFGF), VEGF receptor 2 (Flk-1), CD31, CD34 and Ki-67/MIB-1. The correlation of vasohibin-1 immunoreactivity with overall survival (OS), and disease-free survival (DFS) of the patients with breast carcinoma was also evaluated. In addition, we evaluated Ki-67 and CD31, and Ki-67 and vasohibin-1 double-immunostaining for further characterization of neovascularization. Vasohibin-1 was detected in endothelial cells of human breast and its immunodensity was significantly higher in IDC and inflammatory lesions than the other types (P<0.001). In addition, a significant positive correlation was detected between vasohibin-1 and VEGF-A, bFGF or Flk-1 (P<0.001). There was also positive associations between vasohibin-1 and OS (P=0.004) and between vasohibin-1 and DFS (P Collapse

Key Words Collapse

MESH Headings

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Breast Neoplasms/blood supply
• Breast Neoplasms/mortality
• Cell Cycle Proteins/analysis
• Cell Cycle Proteins/physiology
• Feedback, Physiological
• Female
• Humans
• Middle Aged
• Neoplasm Staging
• Neovascularization, Pathologic/etiology
• Platelet Endothelial Cell Adhesion Molecule-1/analysis
• Vascular Endothelial Growth Factor A/analysis
• Vascular Endothelial Growth Factor A/antagonists & inhibitors

Collapse

Grants Collapse

Affiliation(s)

Kentaro Tamaki Department of Surgical Oncology, Tohoku University School of Medicine, and Department of Pathology, Tohoku University Hospital, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan.
Takuya Moriya
Yasufumi Sato
Takanori Ishida
Yohei Maruo
Kousuke Yoshinaga
Noriaki Ohuchi
Hironobu Sasano

Collapse