Hypoxia,hypoxia-inducible factor-1α and vascular endothelial growth factor in a murine model of Schistosoma mansoni infection

Schistosomiasis mansoni is a chronic parasitic disease where much of the symptomatology is attributed to granuloma formation, an immunopathological reaction against Schistosoma eggs. To more clearly understand the immunopathology of schistosomiasis, the tissue microenvironment generated by S. mansoni infected mice was investigated. Using the hypoxia marker pimonidazole, we provide immunohistochemical evidence that hypoxia occurred in inflammatory cells infiltrated around the eggs and cells surrounding granulomas in the liver, intestine, spleen and lungs of infected mice. Hypoxia-inducible factor-1α (HIF-1α) was mainly expressed in inflammatory cells surrounding the eggs and in hepatocytes surrounding cellular and fibrocellular granulomas in infected mouse liver. HIF-1α expression was also verified in granulomas in the other tissues tested (intestine, spleen and lungs). Vascular endothelial growth factor (VEGF) expression was observed in the extracellular space surrounding inflammatory cells in liver granuloma. The VEGF expression pattern verified in infected mouse liver was very similar to that observed in the other tissues tested. A strong positive correlation occurred between pimonidazole binding and HIF-1α and VEGF expression in the tissues tested, except for lung. This work is the first evidence that infection by a helminth parasite, S. mansoni, produces a hypoxic tissue microenvironment and induces HIF-1α and VEGF expression.     

Angiogenesis and expression of vascular endothelial growth factor, tumour necrosis factor-α and hypoxia inducible factor-1α in canine renal cell carcinoma

The aim of the present study was to determine the distribution and characteristics of microvessels in various histological types of canine renal cell carcinoma (RCC). The study compared microvessel density (MVD) and distribution of blood vessels according to histological type and evaluated the presence of angiogenesis-related proteins. Nine archival samples of canine RCC were studied. MVD was calculated as the mean number of blood vessels per mm(2). The diameter of blood vessels was calculated by determining either the length of the long axis of blood vessels (diameter(max)) or the mean distance from the centre of each blood vessel to the tunica adventia (diameter(mean)). A significant difference in MVD was evident between RCCs and normal kidneys (46.6 ± 28.0 versus 8.4 ± 2.2 microvessels/mm(2)). Diameter(max) in canine RCCs (34.1 ± 14.7 μm) was also significantly different from normal canine kidney (23.2 ± 3.4 μm). Vascular endothelial growth factor (VEGF) was expressed by tumour cells and vascular endothelial cells and tumour necrosis factor (TNF)-α expression was observed in vascular endothelial cells in both neoplastic and normal kidney. Although VEGF is involved in angiogenesis and correlates with tumour stage of development, no correlation was found between VEGF expression and MVD. Tumour-associated macrophages expressing TNF-α and hypoxia inducible factor 1α were identified in peritumoural tissue and may play an important role in angiogenesis.     

Levels and patterns of expression of hypoxia-inducible factor-1α, vascular endothelial growth factor, glucose transporter-1 and CD105 in adenoid cystic carcinomas with high-grade transformation

Costa A F, Tasso M G, Mariano F V, Soares A B, Chone C T, Crespo A N, Fresno M F, Llorente J L, Suárez C, de Araújo V C, Hermsen M & Altemani A
(2012) Histopathology  60, 816–837 Levels and patterns of expression of hypoxia‐inducible factor‐1α, vascular endothelial growth factor, glucose transporter‐1 and CD105 in adenoid cystic carcinomas with high‐grade transformation Aims: To compare the expression of proteins regulated by hypoxia between adenoid cystic carcinoma (ACC) with and without high‐grade transformation (HGT). Methods and results: In eight ACC–HGT and 18 ACC without HGT, expression of hypoxia‐inducible factor‐1 (HIF‐1α), vascular endothelial growth factor (VEGF), glucose transporter‐1 (GLUT‐1) and microvascular density (MVD) by CD105 (a hypoxia‐inducible protein expressed in angiogenic endothelial cells) was determined. Expression levels of HIF‐1α and VEGF as well as CD105‐MVD did not differ significantly between: (i) transformed and conventional areas (TA and CA, respectively) of ACC–HGT, (ii) CA and ordinary ACC. HIF‐1α was detected in 100% of cases and presented a diffuse expression pattern. No significant association was found between levels of HIF‐1α expression and tumour size, metastasis and recurrence. GLUT‐1 showed a prostromal expression pattern and was observed exclusively in TA (three of six cases) and in only three of 14 ACC. Conclusions: Both the absence of significant alterations in levels of expression of HIF‐1α, VEGF and CD105 and the patterns of expression of HIF‐1α and GLUT‐1 suggest that hypoxia may not play a key role in the process of high‐grade transformation of ACC. Although HIF‐1α expression is a common finding in ACC, it cannot be used as a marker of tumour aggressiveness.     

Expression of Hypoxia-inducible factor 1-�� and Vascular endothelial growth factor�CC in locally advanced breast cancer patients

BACKGROUND:

Locally advanced breast cancers are more prevalent in underdeveloped countries. Targeted therapy has been improved to identify hallmarks that are specific to these subtypes of tumors.

OBJECTIVES:

We aimed to prospectively assess the expression of Hypoxia inducible factor-1 α and vascular endothelial growth factor-C in locally advanced breast cancer patients.

METHODS:

Thirty women underwent incisional biopsies for the histopathological diagnosis of breast carcinoma and participated in neoadjuvant chemotherapy. The association of Hypoxia inducible factor-1 α and vascular endothelial growth factor-C with age, tumor size, histological grade, clinical staging, hormonal and axillary status, clinical and pathological response after neoadjuvant chemotherapy, expression of estrogen and progesterone receptors, and the presence of c-erbB-2 antigen was studied.

RESULTS:

Hypoxia inducible factor-1 α expression and Vascular endothelial growth factor-C expression were observed in 66.7% and 63.3% of all patients, respectively, and were marginally associated with each other (p = 0.06). Among the studied variables, only positive axillary status was associated with the presence of HIF-1α (p = 0.02). Complete pathological response was significantly associated (p = 0.04) with the expression of vascular endothelial growth factor-C prior to neoadjuvant chemotherapy.

CONCLUSION:

We concluded that Hypoxia inducible factor-1 α was associated with a poor prognosis and that vascular endothelial growth factor-C could be used as a predictive factor in locally advanced breast cancer patients with complete pathological response after neoadjuvant chemotherapy.     

Expression and function of transforming growth factor β in melioidosis

Melioidosis, caused by the Gram-negative bacterium Burkholderia pseudomallei, is an important cause of community-acquired sepsis in Southeast Asia and northern Australia. An important controller of the immune system is the pleiotropic cytokine transforming growth factor β (TGF-β), of which Smad2 and Smad3 are the major signal transducers. In this study, we aimed to characterize TGF-β expression and function in experimental melioidosis. TGF-β expression was determined in 33 patients with culture-proven infection with B. pseudomallei and 30 healthy controls. We found that plasma TGF-β concentrations were strongly elevated during melioidosis. In line with this finding, TGF-β expression in C57BL/6 mice intranasally inoculated with B. pseudomallei was enhanced as well. To assess the role of TGF-β, we inhibited TGF-β using a selective murine TGF-β antibody. Treatment of mice with anti-TGF-β antibody resulted in decreased lung Smad2 phosphorylation. TGF-β blockade appeared to be protective: mice treated with anti-TGF-β antibody and subsequently infected with B. pseudomallei showed diminished bacterial loads. Moreover, less distant organ injury was observed in anti-TGF-β treated mice as shown by reduced blood urea nitrogen (BUN) and aspartate transaminase (AST) values. However, anti-TGF-β treatment did not have an effect on survival. In conclusion, TGF-β is upregulated during B. pseudomallei infection and plays a limited but proinflammatory role during experimental melioidosis.     

Role of heat shock protein 27 in transforming growth factor-β-stimulated vascular endothelial growth factor release in osteoblasts

We have previously reported that transforming growth factor-β (TGF-β) stimulates heat shock protein?27 (HSP27) induction via p44/p42 mitogen-activated protein (MAP) kinase, p38 MAP kinase and stress-activated protein kinase/c-Jun N-terminal kinase in osteoblast-like MC3T3-E1 cells, and that the release of vascular endothelial growth factor (VEGF) is induced by TGF-β in these cells. In the present study, we investigated the effect of HSP27 knockdown on the TGF-β-stimulated VEGF release in these cells. Gene silencing using short interfering RNA against HSP27 (HSP27-siRNA) significantly suppressed the TGF-β-induced VEGF release. Immunofluorescence microscopy also revealed that HSP27-siRNA suppressed the TGF-β-stimulated VEGF induction as well as the reduction of HSP27 induction in these cells. However, the mRNA expression of VEGF stimulated by TGF-β was not reduced even in cells transfected with HSP27-siRNA. These results strongly suggest that HSP27 induction is critical for TGF-β-induced VEGF release in osteoblasts.     

Role of vascular endothelial growth factor in protein loss of Ménétrier's disease

Vascular endothelial growth factor (VEGF) promotes protein leakage from blood vessels and endothelial cell growth. The expression of transforming growth factor (TGF)-alpha and its receptor is increased in the gastric mucosa of patients with Ménétrier's disease. Since TGF-alpha stimulates the expression of VEGF mRNA in cultured keratinocytes, we hypothesized that VEGF may play an important role in the protein leakage of Ménétrier's disease. Immunohistochemistry was performed using specific antibodies against VEGF and CD31 in gastric tissue specimens from 7 patients with Ménétrier's disease and 10 controls. The effect of recombinant TGF-alpha on VEGF production by cultured lamina propria mononuclear cells (LPMCs) was assessed. VEGF expression was detected for LPMCs and occasional epithelial cells of the gastric mucosa of Ménétrier's patients. VEGF-positive LPMCs were increased in tissues from patients with Ménétrier's disease (P<0.001). Of the LPMCs, T-lymphocytes and macrophages were the major sources of VEGF. CD31-positive blood vessels were increased in Ménétrier's tissue. (P<0.05). Recombinant TGF-alpha induced the production of VEGF in cultured LPMCs (P<0.05). In conclusion, the increased expression of VEGF, as a result of overproduction of TGF-alpha, may play a key role in the pathophysiology of Ménétrier's disease.     

Dual functionalization of titanium with vascular endothelial growth factor and β-defensin analog for potential application in keratoprosthesis

Functionalization of material surfaces can improve their biointegration and bactericidal effect. To expand the biomedical applications of titanium in artificial cornea implantation surgery, titanium alloy substrates were coated with polydopamine and dual bound with recombinant vascular endothelial growth factor (VEGF) and anti-microbial peptide (AMP), SESB2V. Successful chemical binding was assessed with attenuated total reflectance-Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Coating thickness was assessed by atomic force microscopy. Cellular studies revealed that the functionalized substrates displayed the abilities to enhance primary human corneal fibroblast adhesion, proliferation, and viability. Angiogenesis assay with human mesenchymal stem cells was used to verify the biological functions of immobilized VEGF while bactericidal assay was evaluated for the anti-microbial activities of immobilized SESB2V peptide. We found that the titanium surface that was sequentially functionalized with VEGF and SESB2V had enhanced fibroblast proliferation and anti-microbial properties. The incorporation of such peptides into an artificial cornea implant is important for implant-tissue integration and wound healing. This may improve implant integration and reduce the risk of device infection following artificial cornea implantation.     

Expression of laminin β2: A novel marker of hypoxia in pituitary adenomas

Some studies indicate that pituitary adenoma tissues are hypovascular and have lower oxygen saturation relative to the normal pituitary gland and suggest that this may induce hypoxia. Our previous study showed that laminin β2 mRNA is upregulated under hypoxic conditions (1% oxygen) but not under normoxic conditions (21% oxygen) in the HP-75 cell line. In the present study, we further investigated the expression of laminin β1, 2, or 3 chain,under hypoxic and normoxic conditions in HP-75 cells using Western blotting. We found that only laminin β2 had a significantly higher expression under hypoxia than under normoxia in the HP-75 cell line. The expression of laminin β chains was investigated by fluorescent immunohistochemistry of paraffin-embedded sections of tissue from pituitary adenomas of 42 cases (30 cases without apoplexy and 12 with apoplexy) categorized according to Knosp grading and tumor size. We found that only laminin β2 expression correlated significantly with tumor size, but did not correlate with apoplexy and invasiveness. In conclusion, laminin β2 can be regarded as a surrogate marker of hypoxia-as its level is significantly elevated under hypoxic conditions, and it is predominantly expressed in pituitary macroadenomas.     

Expression of vascular endothelial growth factor (VEGF), hypoxia inducible factor 1 alpha (HIF-1α), and transforming growth factors β1 (TGFβ1) and β3 (TGFβ3) in gestational trophoblastic disease

The aim of this study was to investigate the relationship between the expression of vascular endothelial growth factor (VEGF), transforming growth factor β (TGF-β1 and TGF-β3), and hypoxia inducible factor 1 alpha (HIF-1α) in gestational trophoblastic diseases to highlight the possible histogenesis.     

Differential expression of hypoxia-inducible factor 1α in non-small cell lung cancer and small cell lung cancer

OBJECTIVES:

The aim of this study was to compare the expression of hypoxia-inducible factor 1α and vascular endothelial growth factor in small cell lung cancer and subtypes of non-small cell lung cancer and examine their relationships with clinicopathologic factors, response to treatment and survival.

METHODS:

We examined samples obtained by bronchial endoscopic biopsy from 55 patients with inoperable lung cancer (16 with adenocarcinoma, 17 with squamous cell carcinoma, and 22 with small cell lung cancer). Hypoxia-inducible factor 1α and vascular endothelial growth factor were detected using immunohistochemistry. The diagnosis, treatment, and follow-up of patients were conducted according to the standard practice.

RESULTS:

A significant difference (p = 0.022) in hypoxia-inducible factor 1α expression was observed between non-small cell lung cancer (75.8% positive) and small cell lung cancer (45.5% positive). The frequency of hypoxia-inducible factor 1α nuclear expression was 88.2% in squamous cell carcinoma, 62.5% in adenocarcinoma, and 45.5% in small cell lung cancer. A significant correlation was observed between hypoxia-inducible factor 1α and vascular endothelial growth factor expression (Fisher''s exact test, p = 0.001) when all types of lung cancer were examined, either collectively or separately.

CONCLUSIONS:

The expression of hypoxia-inducible factor-1α differs significantly between subtypes of lung cancer. These findings could help elucidate the biology of the different types of non-operable lung carcinomas and have implications for the design of new therapeutic approaches for lung cancer.     

β-arrestin1 over-expression is associated with an unfavorable prognosis in lung adenocarcinomas and correlated with vascular endothelial growth factor

The aim of this study was to examine β-arrestin1 expression in patients with lung adenocarcinoma (ADC) and explore the relationship of β-arrestin1 protein with clinicopathologic factors, vascular endothelial growth factor (VEGF) and prognosis. A total of 105 surgically resected lung adenocarcinoma patients were recruited for the study. The expression of β-arrestin1 and VEGF were determined by immunohistochemistry (IHC). The score measuring the β-arrestin1 and VEGF were calculated by combining the percentage of positive cells and the intensity of staining. Kaplan-Meier method and multivariable Cox proportional hazards regression analyses were used to examine the relationship between β-arrestin1 and survival. The results demonstrated that a notably higher level of β-arrestin1 expression was found in lung ADC tissues. We also found that an elevated nuclear Β-arrestin1 correlates with higher intratumoral VEGF (P = 0.007). β-arrestin 1 over-expression indicated a poor 5-year overall survival (P = 0.016), and the Cox regression model confirmed that β-arrestin1 over-expression were independent prognostic factor for tumor progression (P = 0.027) and unfavorable overall survival (P = 0.015). We conclude that β-arrestin1 had a high expression in ADC and β-arrestin1 may be a promising biomarker to identify individuals with poor prognosis for patients with ADC.