Wang S

Overexpression of macrophage migration inhibitory factor induces angiogenesis in human breast cancer.

Macrophage migration inhibitory factor (MIF) is known to be an important contributor to tumor progression. Overexpression of MIF has been reported in different types of tumors. However, the correlation between MIF expression and tumor pathologic features in patients with breast cancer has not been elucidated. In this study, we examined the expression of MIF, vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) in human tissues with or without tumor. In addition, we investigated the expression of MIF in MDA-MB-231, MCF-7 (breast cancer cell lines) and MCF-10A (epithelial cell line) cells, and its effect on VEGF and IL-8. We found that MIF was overexpressed in breast cancer tissues compared with normal ones. The level of MIF showed the positive correlation between the expression of IL-8 and tumor microvessel density (MVD). The patients with positive MIF expression in tumor tissues showed a significantly worse disease-free survival compared with negative ones. Increased MIF serum levels were also found to correlate with higher levels of IL-8 in the sera of the patients with breast cancer. In vitro experiments successfully detected MIF in breast cell lines. However, the expression level of it by normal epithelial cells was much less than that of cancer cells. Exogenous MIF did not cause endothelial tube formation and migration but induced a dose dependent increase in VEGF and IL-8 secretion in breast cancer cell lines. In summary, our studies show that human breast cancer tissue expresses MIF. Its in vitro effect on VEGF and IL-8 indicates that MIF may contribute to tumor in angiogenesis and thus play an important role in the pathogenesis of breast cancer.

Combination of stromal-derived factor-1α and vascular endothelial growth factor gene-modified endothelial progenitor cells is more effective for ischemic neovascularization

BACKGROUNDnRecruitment and entrapment of bone marrow-derived endothelial progenitor cells (EPCs) is important in vascular endothelial growth factor (VEGF)-induced angiogenesis. EPC mobilization and differentiation are modulated by stromal-derived factor-1alpha (SDF-1alpha/CXCL12), another important chemokine. In this study, we investigated the hypothesis that SDF-1alpha and VEGF might act synergistically on EPC-mediated vasculogenesis.nnnMETHODSnEPCs were isolated and cultured from human peripheral blood, then transduced with retroviral vectors pBabe containing human VEGF(165) complimentary DNA (Td/V-EPCs) and pBabe wild-type (Td/p-EPCs). EPC migration activity was investigated with a modified Boyden chamber assay. EPC apoptosis induced by serum starvation was studied by annexin V assays. The combined effect of local administration of SDF-1alpha and Td/V-EPC transplantation on neovascularization was investigated in a murine model of hind limb ischemia.nnnRESULTSnOver-expression of hVEGF(165) increased SDF-1alpha-mediated EPC migration. SDF-1alpha-mediated migration was significantly increased when EPCs were modified with VEGF (Td/V-EPCs) vs when VEGF was not present (Td/p-EPCs) or when VEGF alone was present (Td/V-EPCs; 196.8 +/- 15.2, 81.2 +/- 9.8, and 67.4 +/- 7.4/mm(2), respectively P < .001). SDF-1alpha combined with VEGF reduced serum starvation-induced apoptosis of EPCs more than SDF-1alpha or VEGF alone (P < .001). To determine the effect of this combination in vivo, SDF-1alpha was locally injected alone into the ischemic hind limb muscle of nude mice or combined with systemically injected Td/V-EPCs. The SDF-1alpha plus VEGF group showed significantly increased local accumulation of EPCs, blood-flow recovery, and capillary density compared with the other groups. The ratio of ischemic/normal blood flow in Td/V-EPCs plus SDF-1alpha group was significantly higher (P < .01), as was capillary density (capillaries/mm(2)), an index of neovascularization (Td/V-EPCs plus SDF-1alpha group, 863 +/- 31; no treatment, 395 +/-13; SDF-1alpha, 520 +/- 29; Td/p-EPCs, 448 +/- 28; Td/p-EPCs plus SDF-1alpha, 620 +/- 29; Td/V-EPCs, 570 +/- 30; P < .01). To investigate a possible mechanistic basis, we showed that VEGF up-regulated the receptor for SDF-1alpha, CXCR4, on EPCs in vitro.nnnCONCLUSIONnThe combination of SDF-1alpha and VEGF greatly increases EPC-mediated angiogenesis. The use VEGF and SDF-1alpha together, rather than alone, will be a novel and efficient angiogenesis strategy to provide therapeutic neovascularization.

Circulating tissue factor positive microparticles in patients with acute recurrent deep venous thrombosis

INTRODUCTIONnCirculating tissue factor positive microparticles (MPTF) were reported in a wide range of diseases with thrombotic tendency. Though D-dimer assay had a high negative predictive value for deep venous thrombosis (DVT) recurrence, there are currently no reliable positive predictors for recurrent DVT. We therefore quantified MPTF in patients with acute recurrent DVT to determine whether MPTF levels could be used to predict recurrent DVT.nnnMATERIALS AND METHODSnMicroparticles (MPs) were isolated from plasma of initial DVT patients (n=25), recurrent DVT patients (n=25) and sex- and age-matched healthy individuals (n=25), stained with annexin V, cell-specific monoclonal antibodies (MoAbs) and a MoAb directed against tissue factor (TF), and analyzed by flow cytometry. We also determined the plasma procoagulant activity with a Human TF Chromogenic Activity Assay Kit.nnnRESULTSnWe found total MPTF to be elevated in recurrent DVT patients versus normal individuals (P=0.001). The number of monocyte-derived MPTF in both initial and recurrent DVT was higher than in normal individuals (P<0.01, respectively). The platelet and endothelial cell derived MPTF in recurrent DVT were significantly increased relative to other MPTF (P<0.05), although there was no difference between initial DVT patients and normal individuals. We demonstrated elevated procoagulant activity of platelet-free plasma in DVT patients relative to normal individuals, and a positive correlation with MPTF.nnnCONCLUSIONSnThe elevated MPTF could be a potentially predictor for DVT recurrence. Further studies are needed to validate its sensitivity and specificity.

Epstein-Barr virus and breast cancer: Serological study in a high-incidence area of nasopharyngeal carcinoma

We investigated IgA and IgG levels against EBV viral capsid antigen (VCA) and nuclear antigen-1 (EBNA-1) in serum of 223 women with breast cancer (BC) and 309 controls in Guangzhou, China. VCA IgA levels were significantly associated with an elevated risk of BC, with adjusted ORs (95%CIs) of 1.70 (1.05-2.76) (seropositivity) and 2.21 (1.11-4.40) (unit increases in OD value). This association was stronger among young, lean, and HER2+ women. The EBNA-1 IgA levels in OD value, but not seropositivity, were associated with an increased risk of BC among ER+, PR+, and HER2+ patients. None of the IgG variables was related to BC. These results suggest the EBV association with BC in an endemic area of nasopharyngeal carcinoma.

In vitro differences between smooth muscle cells derived from varicose veins and normal veins

OBJECTIVEnThe theory of primary venous dilatation leading to secondary valvular incompetence and varicose vein formation has received more attention nowadays. Although many studies have investigated the role of the main components of the venous wall in the development of varicose veins, the leading cause remains unknown. The present study was designed to establish the role of smooth muscle cells (SMCs) of the tunica media on the pathogenesis of varicose veins by analyzing the phenotypic and functional differences between SMCs derived from varicose veins and normal veins.nnnMETHODSnSMCs were isolated and cultured from saphenous veins of patients with varicose veins and normal veins. Cell proliferation and migration rates were compared. Expression of phenotype-dependent markers and matrix metalloproteinase-2 (MMP) production were analyzed by immunoblotting. Total collagen synthesis was evaluated by measuring the radioactivity of L-[3, 4-(3)H]proline in the media and the cell layer.nnnRESULTSnSMCs derived from varicose veins demonstrated increased proliferation (2-fold, P < .01), migration (3-fold, P < .001), MMP-2 production (3-fold, P < .01), and collagen synthesis (>2-fold, P < .001), with decreased expression of phenotype-dependent markers compared with SMCs derived from normal veins (P < .05).nnnCONCLUSIONnSMCs derived from varicose veins are more dedifferentiated and demonstrate increased proliferative and synthetic capacity than SMCs derived from normal veins. These properties may contribute to the remodeling of the venous wall and the weakening of its antipressure capacity.

Endovascular treatment of arch and proximal thoracic aortic lesions.

OBJECTIVEnTo analyze at one institution the endovascular treatment for aortic arch and proximal thoracic aortic lesions, categorize open arch reconstruction, and make preliminary recommendations based on pathology (dissection vs aneurysm), and anatomical extent of disease.nnnMETHODSnA retrospective review of aortic arch and descending thoracic aortic lesions managed with endovascular treatment between June 2002 and June 2007.nnnRESULTSnThirty-four patients received endovascular repair for aortic dissection (n = 28) and aneurysm (n = 6). Open supra-aortic transposition or debranching of the great vessels was performed in 14 cases of dissection (50%) and six cases (100%) of aneurysm. In 14 dissections, the entry tear was located in the distal aortic arch, enabling the left subclavian artery to be sealed without reconstruction. The procedures were successful in 33 patients (97.1%); one intraoperative death occurred. Type I endoleaks were found intraoperatively in eight cases. After management with balloon angioplasty and by extending the stent implantation, the endoleaks resolved in four cases and decreased in four cases. One patient with Stanford type A dissection died from an unknown cause 3 months after treatment. The overall survival rate was 94.1% (32/34), and all bypass grafts remained patent during the follow-up period.nnnCONCLUSIONSnEndovascular stent grafting is a safe and effective method for the treatment of aortic arch lesions. Transposition of the supra-aortic great vessels can be effectively combined with endovascular stent grafting to ensure both cerebral blood supply and enough landing area for the stent graft.

Preoperative angiography and transarterial embolization in the management of carotid body tumor: a single-center, 10-year experience.

BACKGROUND:Sixty percent of paragangliomas are located unilaterally at the carotid bifurcation. These are referred to as carotid body tumors (CBTs). OBJECTIVE:To present our 10-year experience in the management of patients with CBTs, and to evaluate the efficacy of angiography and preoperative embolization technique in this retrospective study. METHODS:Sixty-two patients with surgically removed CBTs (Shamblin class II and III), were divided into two groups. Group I, the preoperative embolization group, included 33 patients with 11 class II lesions and 25 class III lesions. Group II, the group that had surgery only, without preoperative embolization, included 29 patients with 9 class II lesions and 21 class III lesions. Comparisons were made between the groups in terms of mean intraoperative blood loss, mean operation time, mean postoperative hospital stay, and clinical complications. RESULTS:In group I, post-embolization angiography demonstrated complete tumor devascularization in 25 (76%) lesions and partial devascularization in 11 (24%) lesions. All but 1 (2%) lesion were completely excised. Mean intraoperative blood loss, mean operation time, and mean hospital stay were 354.8 ± 334.4 mL, 170.3 ± 75.4 min, 8.0 ± 2.1days in group I and 656.4 ± 497.4 mL, 224.6 ± 114.0 min, 9.5 ± 3.5days in group II, respectively. In group II, 27 lesions (91%) were completely removed. The transient ischemic attack (TIA) and cranial nerve injury incidence rates were 10.3% and 13.8% in group II and only 3% for TIA in group I. CONCLUSION:These results suggest angiography is highly valuable for the diagnosis of CBT. Preoperative selective embolization of CBT is an effective and safe adjunct for surgical resection, especially for Shamblin class II and III tumors.

Antithrombotic effect of grape seed proanthocyanidins extract in a rat model of deep vein thrombosis

OBJECTIVEnProanthocyanidins are abundantly found in grape seeds and have been suggested to inhibit the pathogenesis of systemic diseases. We investigated the antithrombotic effects of proanthocyanidins in a rat model of deep vein thrombosis (DVT) and examined the underlying mechanisms.nnnMETHODSnDVT was induced in rat model by inferior vena cava (IVC) ligation. Grape seed proanthocyanidins extract (GSPE, 400 mg/kg/d) dissolved in saline (2 mL) was orally administered to the experimental rats. Control rats were administrated saline (2 mL) only. The thrombi were harvested and weighed. The IVC was analyzed histologically and by transmission electron microscopy. The cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay. Expression of cellular adhesion molecules (CAMs) in thrombi was examined by Western blot.nnnRESULTSnGSPE significantly reduced thrombus length and weight (P < .01) and protected the integrity of the endothelium. GSPE inhibited thrombogenesis-promoting factors P-selectin, von Willebrand factor, and CAMs, and promoted thrombogenesis-demoting factors CD34, vascular endothelial growth factor receptor-2, and ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type one motif, member 13). Compared with the control, GSPE significantly lowered the cytokines IL-6 (74.19 ± 13.86 vs 189.54 ± 43.76 pg/mL; P < .01), IL-8 (80.71 ± 21.42 vs 164.56 ± 39.54 pg/mL; P < .01), and TNF-α (43.11 ± 17.58 vs 231.84 ± 84.11 pg/mL; P < .01).nnnCONCLUSIONSnGSPE significantly inhibited the propagation of thrombus induced by IVC ligation in a rat model. The antithrombotic properties of proanthocyanidins are likely to be directly associated with endothelial protection and regeneration, platelet aggregation, and inhibition of inflammatory cell and thrombus adhesion. Thus, proanthocyanidins may have a clinical application in DVT treatment.

The in vivo performance of small-caliber nanofibrous polyurethane vascular grafts.

BackgroundIn a previous in vitro study, we confirmed that small-caliber nanofibrous polyurethane (PU) vascular grafts have favorable mechanical properties and biocompatibility. In the present study, we examined the in vivo biocompatibility and stability of these grafts.MethodsForty-eight adult male beagle dogs were randomly divided into two groups receiving, respectively, polyurethane (PU) or polytetrafluoroethylene (PTFE) grafts (nu2009=u200924 animals / group). Each group was studied at 4, 8, 12, and 24 weeks after graft implantation. Blood flow was analyzed by color Doppler ultrasound and computed tomography angiography. Patency rates were judged by animal survival rates. Coverage with endothelial and smooth muscle cells was characterized by hematoxylin-eosin and immunohistological staining, and scanning electron microscopy (SEM).ResultsPatency rates were significantly higher in the PU group (pu2009=u20090.02 vs. PTFE group). During the first 8 weeks, endothelial cells gradually formed a continuous layer on the internal surface of PU grafts, whereas coverage of PTFE graft by endothelial cells was inhomogeneous. After 12 weeks, neointimal thickness remained constant in the PU group, while PTFE group showed neointimal hyperplasia. At 24 weeks, some anastomotic sites of PTFE grafts became stenotic (pu2009=u20090.013 vs. PU group). Immunohistological staining revealed a continuous coverage by endothelial cells and an orderly arrangement of smooth muscle cells on PU grafts. Further, SEM showed smooth internal surfaces in PU grafts without thrombus or obvious neointimal hyperplasia.ConclusionsSmall-caliber nanofibrous PU vascular grafts facilitate the endothelialization process, prevent excessive neointimal hyperplasia, and improve patency rates.

Somatic mutations in exon 17 of the TEK gene in vascular tumors and vascular malformations

OBJECTIVEnAs a common disease, the molecular etiology of noninherited vascular anomalies is still poorly understood. Recently, somatic mutations in exon 17 of the endothelial cell tyrosine kinase receptor Tie-2 (encoded by TEK) were identified in 49.1% of patients with common sporadic venous malformation, a subtype of vascular anomalies. We assessed whether such a mutational region also had a role in the Chinese population or in other subtypes of noninherited vascular anomalies (vascular tumors and vascular malformations).nnnMETHODSnDirect sequencing of polymerase chain reaction (PCR)-amplified DNA, extracted from 139 lesions in 129 individuals with noninherited vascular anomalies (vascular tumors or vascular malformations) and 60 control samples, was used for detecting the mutations in exon 17 of the TEK gene. Mutations were confirmed by allele-specific PCR. Clone sequences were then used for the mutations identified for the first time. We also explored the associations between these mutations and clinical characteristics (gender, onset age, number of lesions, severity, category, and recurrence of the disease) in both vascular tumors and vascular malformations.nnnRESULTSnTwo somatic TEK mutations (Y897C, R915C) were identified in vascular tumors, and seven somatic TEK mutations (Y897H, Y897C, L914F, R915C, S917I, R918C, R918H) were identified in vascular malformations. Among these mutations, R918C (2,752 C > T) and R918H (2,753 G > A) were first identified in noninherited vascular anomalies. Somatic TEK mutations were detected in lesions from 4 of 23 (17.4%) vascular tumors and 35 of 106 (33.0%) vascular malformations, where most mutations were single substitutions in vascular tumors (100%) and vascular malformations (88.6%), while the remainders were double substitutions. In addition to the reported venous malformation, such mutations were identified in some other subtypes of vascular anomalies, including vascular tumors (infantile hemangioma, pyogenic granuloma, and epithelioid hemangioma) and vascular malformations (capillary malformation, arteriovenous malformation, capillary lymphatic malformation, and capillary arteriovenous malformation). By contrast, these mutations were absent from the control tissues or blood. However, mutations showed no association (P > .05) with clinical characteristics in vascular anomalies or either of its two types (vascular tumors or vascular malformations).nnnCONCLUSIONSnOur study revealed that somatic mutations in exon 17 of the TEK gene were more common in noninherited vascular anomalies than previously reported. Furthermore, such substitutions may shed new light on the molecular etiology, diagnosis, and potential therapeutic targets of vascular anomalies.