Previously, we described the isolation and characterization of the first zebrafish neuropilin gene, which we now call nrp1a, and found its protein to be a mediator of <em>vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> (VEGF)-dependent angiogenesis [Proc. Natl Acad. Sci. USA 99 (2002) 10470]. Subsequently, we have isolated three other full-length neuropilin genes (nrp1b, nrp2a, and nrp2b) and find that they map to independent zebrafish linkage groups. The nrp1s and nrp2s had differential spatio-temporal gene expression profiles with nrp1a being most prominent in the gut, brain, retina, hypochord, motorneurons, fin bud and mandibular cartilage, nrp1b in the brain, dorsal aorta, melanophores, ventral fin, and heart, nrp2a in the brain, retina, heart, and caudal vessels, and nrp2b in the brain, retina, gut, fin bud, melanophores, heart, and caudal vessels. In addition, we have identified an alternatively-spliced transcript of the nrp1b gene (denoted as nrp1b(s)) which is predicted to encode a soluble form of Nrp1b, containing only the a, b, and c extracellular domains. Transcript expression of nrp1b(s) was different from full-length nrp1b transcript, with prominence in the brain, developing mouth, heart, and fin bud. The NRP1s were tested for VEGF-binding ability. Both 125 kDa Nrp1a and <em>145</em> kDa Nrp1b bound 125I-labelled VEGFA165. In summary, two nrp1 and two nrp2 genes, with expression patterns similar to higher vertebrates, have been isolated from zebrafish.

<em>Vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> (VEGF) is implicated in numerous pathologies through complex relationships with cellular adhesion molecules (CAMs) and inflammation markers. These have not been assessed in non-pathological conditions. Our aim was the evaluation of associations between VEGF and CAM/inflammation molecules in a healthy population, and of possible genomic interplays in order to better apprehend the underlying mechanisms leading to the pathology. We examined the associations between VEGF and ICAM-1, VCAM-1, E-, L-, P-selectins, TNF-α, CRP and IL-6 plasma levels in 403 healthy individuals. Gene expression of CAM/inflammation molecules and VEGF isoforms (121, <em>145</em>, 165, and 189) were quantified in peripheral blood mononuclear cells (PBMCs). The effect of four genetic variants (explaining ≈ 50% of the heritability of circulating VEGF levels) and of their interactions on plasma and mRNA levels of CAM/inflammation molecules was examined. VEGF was associated with ICAM-1 and E-selectin in plasma. In PBMCs, VEGF(<em>145</em>) mRNA was associated with ICAM-1, L-selectin and TNF-α expression. Interactions of the genetic variants were shown to affect ICAM-1, E-selectin, IL-6 and TNF-α plasma levels, while rs4416670 was associated with L-selectin expression. These findings propose a biological connection between VEGF and CAM/inflammation markers. Common genetic and transcriptional mechanisms may link these molecules and control their effect in healthy conditions.

OBJECTIVE

Scatter factor (hepatocyte growth factor) (SF/HGF) is a multifunctional polypeptide growth factor that has been implicated in tumor proliferation, angiogenesis, invasiveness, and metastasis. Little is known of the expression of SF/HGF in human prostatic carcinoma. The aims of this investigation were to quantitate the level of SF/HGF expression in benign versus malignant human prostatic tissues and to assess regulation of SF/HGF expression by human prostatic stromal myofibroblasts.

METHODS

We determined the level of SF/HGF expression in 10 human prostatic tissue samples (5 benign, 5 carcinoma) by Western blot analysis. Five purified growth factors-basic fibroblast growth factor (bFGF), interleukin-1beta (IL-1beta), platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and endothelial growth factor (EGF)-were tested for their capacity to induce SF/HGF expression by a human prostatic stromal myofibroblastic cell line, as assessed by enzyme-linked immunosorbent assay. Supernatant from the normal PrEC prostatic epithelial cell line and the DU 145 carcinoma cell line were assayed for SF/HGF-inducing activity.

RESULTS

SF/HGF exhibited a mean fourfold overexpression in carcinoma tissues compared with benign prostatic tissue. Significant stimulation of SF/HGF expression by prostatic stromal myofibroblasts was detected for IL-1beta (8.1-fold), PDGF (6.2-fold), bFGF (4.0-fold), VEGF (3. 7-fold), and EGF (2.9-fold). DU 145-conditioned media, but not the PrEC-conditioned media, contained SF/HGF-inducing activity, which was determined to include IL-1beta, bFGF, and PDGF by antibody-blocking experiments.

CONCLUSIONS

SF/HGF is overexpressed in human prostatic carcinoma tissues. Prostatic carcinoma cell stimulation of SF/HGF expression by adjacent benign myofibroblastic cells as a type of epithelial-stromal paracrine interaction could potentially influence prostatic carcinoma cell behaviors.

BACKGROUND

Angiogenesis is important in tumor growth and metastasis. Germ-line polymorphisms critical to the angiogenesis pathway have been shown to confer prognostic information in multiple tumor types. These genes include vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS).

METHODS

We extracted DNA from 53 specimens obtained from 21 patients including a primary breast tumor, and/or a histologically involved lymph node, and/or a histologically normal lymph node. We subsequently genotyped all specimens to evaluate two polymorphisms in the eNOS gene and one polymorphism in the VEGF gene.

RESULTS

Chromatographs were generated in 145/159 (91%) samples. When assessing all polymorphisms by site, chromatographs were generated in 42/51 (83%) samples obtained from the primary tumor and 103/108 (95%) from lymph nodes. Chromatographs were generated in 46/53 (87%) samples from the T(-786)C polymorphism in the 5'-flanking region in the eNOS gene, 49/53 (92%) when assessing the Glu298Asp polymorphism in exon 7 in the eNOS gene and 50/53 samples (94%) for the C(936)T polymorphism in the VEGF gene. There was 100% concordance between analyses from the primary tumor, uninvolved lymph node, and involved lymph node from the same case.

CONCLUSIONS

We successfully extracted DNA and genotyped several polymorphisms in two genes important in angiogenesis. These genotypes were determined in breast tumors, but also in involved and uninvolved lymph nodes. There was concordance between the genotypes of germline DNA obtained from uninvolved lymph nodes and those determined in tumor samples, implying that the host angiogenic genotype imprints the tumor genotype.

Primary effusion lymphomas (PEL), rare lymphomas associated with Kaposi's sarcoma-associated herpesvirus (KSHV or HHV-8) infection, present as malignant lymphomatous effusions in body cavities. We have recently found that PEL effusions contain high levels of <em>vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em>/<em>vascular</em> permeability <em>factor</em> (VEGF/VPF). VEGF/VPF, an important regulator of tumor-angiogenesis in vivo, exerts its effects acting through the receptors KDR/Flk-1 and Flt-1 on the <em>endothelial</em> cell membrane. In vitro, the PEL cell lines BC-1, BCP-1 and BCBL-1 produce high levels of VEGF. RT-PCR analysis of RNA from the PEL cell lines amplified the three VEGF/VPF secreted isoforms, VEGF/VPF(121), VEGF/VPF(<em>145</em>) and VEGF/VPF(165). Two of the PEL cell lines express the VEGF/VPF receptor Flt-1, but VEGF did not stimulate proliferation in these cells. SCID/beige mice inoculated intraperitoneally with BCBL-1 cells developed effusion lymphoma of human cell origin with prominent bloody ascites. In contrast, none of the mice treated with a neutralizing anti-human VEGF/VPF antibody developed ascites and effusion lymphoma. Although the precise mechanisms by which VEGF/VPF can promote <em>vascular</em> permeability are not fully understood, VEGF/VPF stimulation of <em>vascular</em> leakage may be critical to the pathogenesis of PEL.

OBJECTIVE

This phase II study evaluated the combination of semaxanib, a small molecule tyrosine kinase inhibitor of vascular endothelial growth factor (VEGF) receptor-2, and thalidomide in patients with metastatic melanoma to assess the efficacy, tolerability, pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of the combination.

METHODS

Patients with metastatic melanoma, who had failed at least one prior biologic and/or chemotherapeutic regimen, were treated with escalating doses of thalidomide combined with a fixed dose of semaxanib.

RESULTS

Twelve patients were enrolled and received 44 courses of semaxanib at the fixed dose of 145 mg/m2 intravenously twice-weekly in combination with thalidomide, commencing at 200 mg daily with intrapatient dose escalation as tolerated. Treatment with semaxanib was initiated 1 day before thalidomide in the first course, permitting the assessment of the PKs of semaxanib alone (course 1) and in combination with thalidomide (course 2). The principal toxicities included deep venous thrombosis, headache, and lower extremity edema. Of ten patients evaluable for response, one complete response lasting 20 months and one partial response lasting 12 months were observed. Additionally, four patients had stable disease lasting from 2 to 10 months. The PKs of semaxanib were characterized by drug exposure parameters comparable to those observed in single-agent phase II studies, indicating the absence of major drug-drug interactions. Maximum semaximib plasma concentration values were 1.2-3.8 microg/ml in course 1 and 1.1-3.9 microg/ml in course 2. The mean terminal half-life was 1.3 ( +/- 0.31) h. Biological studies revealed increasing serum VEGF concentrations following treatment in patients remaining on study for more than 4 months.

CONCLUSIONS

The combination of semaxanib and thalidomide was feasible and demonstrated anti-tumor activity in patients with metastatic melanoma who had failed prior therapy. Further evaluations of therapeutic strategies that target multiple angiogenesis pathways may be warranted in patients with advanced melanoma and other malignancies.

BACKGROUND

Extravasation is a critical step in cancer metastasis, in which adhesion of intravascular cancer cells to the vascular endothelial cells is controlled by cell surface adhesion molecules. The role of interleukin-17 (IL-17), insulin, and insulin-like growth factor 1 (IGF1) in adhesion of prostate cancer cells to the vascular endothelial cells is unknown, which is the subject of the present study.

METHODS

Human umbilical vein endothelial cells (HUVECs) and human prostate cancer cell lines (PC-3, DU-145, LNCaP, and C4-2B) were analyzed for expression of vascular cell adhesion molecule 1 (VCAM-1), integrins, and cluster of differentiation 44 (CD44) using flow cytometry and Western blot analysis. The effects of IL-17, insulin, and IGF1 on VCAM-1 expression and adhesion of prostate cancer cells to HUVECs were examined. The interaction of VCAM-1 and CD44 was assessed using immunoprecipitation assays.

RESULTS

Insulin and IGF1 acted with IL-17 to increase VCAM-1 expression in HUVECs. PC-3, DU-145, LNCaP, and C4-2B cells expressed β1 integrin but not α4 integrin. CD44 was expressed by PC-3 and DU-145 cells but not by LNCaP or C4-2B cells. When HUVECs were treated with IL-17, insulin or IGF1, particularly with a combination of IL-17 and insulin (or IGF1), adhesion of PC-3 and DU-145 cells to HUVECs was significantly increased. In contrast, adhesion of LNCaP and C4-2B cells to HUVECs was not affected by treatment of HUVECs with IL-17 and/or insulin/IGF1. CD44 expressed in PC-3 cells physically bound to VCAM-1 expressed in HUVECs.

CONCLUSIONS

CD44-VCAM-1 interaction mediates the adhesion between prostate cancer cells and HUVECs. IL-17 and insulin/IGF1 enhance adhesion of prostate cancer cells to vascular endothelial cells through increasing VCAM-1 expression in the vascular endothelial cells. These findings suggest that IL-17 may act with insulin/IGF1 to promote prostate cancer metastasis.

BACKGROUND

Diabetic (DM) patients frequently lack autologous vascular tissue required for revascularization procedures and dialysis access creation. We have developed a tissue-engineered graft that uses adipose-derived stem cells (ASC) as endothelial cell substitutes. Here, we compare DM versus nondiabetic (NDM) ASC in terms of isolation efficiency, proliferation, commitment toward endothelial lineage, and seeding onto the luminal surface of a graft.

METHODS

ASC were isolated from liposuction specimens of vascular surgery patients. Proliferation was assessed by constructing growth curves over 14 d. ASC were differentiated in endothelial growth medium (EGM2). Endothelial commitment was assessed by measuring endothelial cell-specific gene expression (CD31, von Willebrand factor) and by cord formation on Matrigel. Finally, ASC were seeded onto a vascular scaffold, flow conditioned, and imaged with confocal microscopy.

RESULTS

Diabetes did not alter ASC isolation efficiency (224,028 ± 20,231 cells/g adipose for DM (n = 53) versus 259,345 ± 15,441 cells/g adipose for NDM (n = 145; P = 0.21). Growth curves for DM (n = 6) and NDM (n = 6) also appeared similar. After culture in EGM2, upregulation of CD31 and von Willebrand factor message was observed in NDM; these markers were found within the primary cultures of DM but no upregulation was observed after culture in EGM2. Both groups exhibited similar cord formation on Matrigel and retention to vascular scaffolds.

CONCLUSIONS

Isolation and proliferation studies suggest that adipose is a promising source of stem cells for tissue engineering in the DM population. The angiogenic potential of DM ASC appears intact; however, differences in acquisition of endothelial cell markers suggest that differentiation may be inhibited or delayed by diabetes.

OBJECTIVE

To evaluate the effect of reactive oxygen species such as hydrogen peroxide on the progression of human colon cancer.

METHODS

Human colon carcinoma cell lines, LS174T and HCT8, were treated respectively with 10(-5), 10(-7) or 10(-9) mol x L(-1) hydrogen peroxide for 24h,and co-cultured with human endothelial cell line ECV-304. The migration of ECV-304 induced by cancer cells was calculated and the expression level of vascular endothelial growth factor in cancer cells was determined by RT-PCR analysis and ELISA. Dactinomycin of 1.5mg x L(-1) which could block transcription of cancer cells was applied to observing the effects of H(2)O(2) on transcriptional activity and the relative half-life of VEGF mRNA. Finally,to evaluate the effect of H2O2 on NF-kappaB activity in colon cancer cells, NF-kappaB in cytoplasm and nucleus of the cells were detected with FITC-tagged antibody and its presence in the nucleus(Fn) vs cytoplasm(Fc) was monitored by measuring the green fluorescence integrated over the nucleus by laser scanning cytometry(LSC).

RESULTS

Exogenouse hydrogen peroxide of low concentration increased the migration of endothelial cell induced by colon cancer cells. When cancer cells were treated with 10(-5) mol x L(-1) H2O2, the migration number of endothelial cells induced by LS174T cells was 203+/-70 and the number induced by HCT8 cells was 145+/-65. The two values were significantly higher than those treated with other concentrations of H2O2 (P<0.01). The expression of vascular endothelial growth factor in cancer cells, which could be blocked by dactinomycin, were increased to a certain degree, while the relative half-life of VEGF mRNA was not prolonged after treatment with hydrogen peroxide. The activity of NF-kappaB in colon cells rose after the cells were exposed to hydrogen peroxide for 24h. The Fn values in HCT8 cells were 91+/-13 (0 mol x L(-1) H2O2) and 149+/-40(10(-5) mol x L(-1) H2O2)(P<0.05), in LS174T cells were 127+/-35(0 mol x L(-1) H2O2) and 192+/-11(10(-5)mol x L(-1) H2O2) (P<0.05). It is similar to the case of VEGF expression in cancer cells.

CONCLUSIONS

Hydrogen peroxide increases vascular endothelial growth factor expression in colon cancer cells, and it is likely that reactive oxygen species such as hydrogen peroxide facilitates the development of colon cancer.

Chordomas are locally invasive tumors that have a tendency to relapse despite optimal treatment. Specific biological markers might be used to describe their behavior. There is currently no agreement regarding the best way to manage intracranial chordomas. We studied the expression of <em>vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> receptor 2 (VEGFR-2), inducible nitric oxide synthase (iNOS), and Ki-M1P in <em>145</em> paraffin-embedded tumors. The purpose of our study was to determine: (a) the role of potent angiogenic <em>factors</em> VEGFR-2 and iNOS and their relationship to each other in skull base chordoma and (b) the role of monocytes/macrophages as a potential iNOS source in the angiogenic process. A series of 74 chordoma patients for a total of <em>145</em> lesions (including 71 recurrent lesions) and 10 specimens from embryonic notochord were investigated for the expression of iNOS, VEGFR-2, Ki-M1P, and CD-34 using immunohistochemistry. In the majority of the chordomas, correlations were found between iNOS and the immunoreactivity of Ki-M1P (r = 0.5303, P < 0.0001). Furthermore, the expressions of Ki-M1P was correlated with VEGFR-2 (r = 0.4181, P < 0.0001). Our results indicate that chordomas may respond to receptor tyrosine kinase inhibitors such as VEGFR-2 or modulators of other downstream signaling molecules. The future of VEGFR-2 and iNOS inhibitors as therapeutic agents in the treatment of chordoma will be clearer over the next years as results of the current clinical trials become available and as the <em>factors</em> regulating angiogenesis and the interactions between these <em>factors</em> are elucidated. However, appropriate functional experiments remain to be conducted to prove such a hypothesis.

BACKGROUND

Peritumoral liver tissue could play a potential role in hepatocellular carcinoma (HCC) progression and patient survival via angiogenesis- and lymphangiogensis-related factors. The prognostic role of these factors in hepatocytes and stromal cells in HCC patients after curative resection remains to be explored.

METHODS

Tumor tissue and surrounding peritumoral tissue were obtained from 145 resected HCC patients without lymph node metastasis (LNM) and 37 resected HCC patients with LNM. Tissue microarrays were constructed from duplicate cores of tumor tissue and surrounding peritumoral tissue from each resected specimen. Immunohistochemistry and real-time polymerase chain reaction were used to evaluate the expression of vascular endothelial growth factor-A (VEGF-A), VEGF-C, VEGF receptor-1(VEGFR-1), VEGFR-2, and VEGFR-3. Macrophage infiltration was determined by CD68 staining. Correlations between the expression of these factors and overall survival (OS) and time to recurrence (TTR) were studied.

RESULTS

The peritumoral expression of VEGF-A, VEGF-C, VEGFR-1, VEGFR-2, and VEGFR-3 were significantly higher than expression of these factors in tumors. VEGFR-1 was mostly located in peritumoral macrophages, while VEGF-C and VEGFR-3 were mostly located in peritumoral hepatocytes. HCC with high peritumoral co-expression of VEGF-C, VEGFR-1, and VEGFR-3 was associated with higher peritumoral distribution of macrophages (0.87%±0.26% versus 0.45%±0.20%), LNM (32.4% versus 12.0%), shorter TTR (10.2 months versus 34.5 months), and poor prognosis (19.4 months versus 49.3 months).

CONCLUSIONS

Expression of VEGF-C, VEGFR-1, and VEGFR-3 in peritumoral liver tissue is associated with a unique type of HCC that has a poorer outcome after hepatectomy.

<AbstractText>Adipose-derived stem cells (ASCs) are a potential adult mesenchymal stem cell source for restoring <em>endothelial</em> function in ischemic tissues. However, the mechanism that promotes ASCs differentiation toward <em>endothelial</em> cells (ECs) is not known.</AbstractText><AbstractText>To investigate the mechanisms of ASCs differentiation into ECs.</AbstractText><AbstractText>ASCs were isolated from clinical lipoaspirates and cultured with DMEM or <em>endothelial</em> cell-conditioned medium. <em>Endothelial</em> cell-conditioned medium induced downregulation of miR-<em>145</em> in ASCs and promoted <em>endothelial</em> differentiation. We identified bFGF (basic fibroblast <em>growth</em> <em>factor</em>) released by ECs as inducer of ASCs differentiation through receptor-induced AKT (protein kinase B) signaling and phosphorylation of FOXO1 (forkhead box protein O1) suppressing its transcriptional activity and decreasing miR-<em>145</em> expression. Blocking bFGF-receptor or PI3K/AKT signaling in ASCs increased miR-<em>145</em> levels. Modulation of miR-<em>145</em> in ASCs, using a miR-<em>145</em> inhibitor, regulated their differentiation into ECs: increasing proliferation, migration, inducing expression of EC markers (VE-cadherin, VEGFR2 [<em>vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> receptor 2], or VWF [von Willebrand <em>Factor</em>]), and tube-like formation. Furthermore, in vivo, downregulation of miR-<em>145</em> in ASCs enhanced angiogenesis in subcutaneously implanted plugs in mice. In a murine hindlimb ischemia model injection of ASCs with downregulated miR-<em>145</em> induced collateral flow and capillary formation evidenced by magnetic resonance angiography. Next, we identified ETS1 (v-ets avian erythroblastosis virus E26 oncogene homolog 1) as the target of miR-<em>145</em>. Upregulation of miR-<em>145</em> in ASCs, by mimic miR-<em>145</em>, suppressed ETS1 expression and consequently abolished EC differentiation and the angiogenic properties of <em>endothelial</em> cell-conditioned medium-preconditioned ASCs; whereas, overexpression of ETS1 reversed the abrogated antiangiogenic capacity of miR-<em>145</em>. ETS1 overexpression induced similar results to those obtained with miR-<em>145</em> knockdown.</AbstractText><AbstractText>bFGF released by ECs induces ASCs differentiation toward ECs through miR-<em>145</em>-regulated expression of ETS1. Downregulation of miR-<em>145</em> in ASCs induce <em>vascular</em> network formation in ischemic muscle.</AbstractText>

<em>Vascular</em> participation manifested by a runny nose (rhinorrhea) is a prominent feature of the acute consequences of rhinovirus infection. <em>Vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> (VEGF) is an angiogenic <em>factor</em> that also induces potent increases in <em>vascular</em> permeability; it is a candidate mediator of rhinorrhea in response to rhinovirus infection as well as contributing to enhanced <em>vascular</em> leakage in rhinovirus-linked asthma exacerbations. It has been shown that rhinovirus induces significant increases in both VEGF protein and mRNA in primary airway fibroblasts [Ghildyal et al. (2005): J Med Virol 75:608-615]. The current studies assessed VEGF responses to rhinovirus in primary culture airway epithelium, in epithelial and fibroblast cell lines and in rhinovirus-infected nasal secretions. Epithelial and fibroblast cells were infected with rhinovirus serotype 16 and VEGF protein and isoforms assessed by ELISA and RT-PCR, respectively. VEGF protein was released by both epithelial and fibroblast cell lines and primary airway epithelial cells in culture but was not increased following rhinovirus infection. PCR products coding for four or five of the six known VEGF isoforms were produced (121, <em>145</em>, 165 and 183, and/or 189 amino acids) in cell lines and primary culture cells, but no specific isoform was linked to rhinovirus infection. Nasal VEGF was also measured in a cohort of asthmatics with verified rhinovirus and respiratory syncytial virus (RSV) infection. VEGF was not raised following rhinovirus infection alone, but was increased significantly if concomitant RSV infection was present. The data suggest that fibroblasts rather than the epithelium may play a key role in VEGF mediated <em>vascular</em> responses after rhinovirus infection. This may aid recruitment of inflammatory cells and contribute to airway inflammation and bronchial obstruction.

Little is known about the <em>vascular</em> and metabolic adaptations that take place in the fetal heart to maintain cardiac function in response to increased load. Chronic fetal anemia has previously been shown to result in increased ventricular mass, increased myocardial <em>vascular</em>ization, and increased myocardial expression of hypoxia-inducible <em>factor</em>-1 (HIF-1) and <em>vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> (VEGF). We therefore sought to determine whether chronic fetal anemia induces expression of HIF-1-regulated angiogenic <em>factors</em> and glycolytic enzymes in the fetal myocardium. Anemia was produced in chronically instrumented fetal sheep by daily isovolemic hemorrhage (80-100 ml) for either 3 (n = 4) or 7 days (n = 11) beginning at 134 days of gestation (term <em>145</em> days). Catheterized, nonbled twins served as controls. Isovolemic hemorrhage over 7 days resulted in decreased fetal hematocrit (37 +/- 1 to 20 +/- 1%) and arterial oxygen content (6.5 +/- 0.4 to 2.8 +/- 0.2 ml O2/dl). Myocardial blood flow and <em>vascular</em>ization were significantly increased after 7 days of anemia. Myocardial HIF-1 protein expression and VEGF (left ventricular), VEGF receptor-1 (right ventricular), and VEGF receptor-2 (right ventricular, left ventricular) mRNA levels were elevated (P < 0.05) in 7-day anemic compared with control animals. Myocardial expressions of the glycolytic enzymes aldolase, lactate dehydrogenase A, phosphofructokinase (liver), and phosphoglycerol kinase were also significantly elevated after 7 days of anemia. Despite the absence of a significant increase in myocardial HIF-1alpha protein in 3-day anemic fetuses, expressions of VEGF, VEGF receptor-1, and the glycolytic enzymes were greater in 3-day compared with 7-day anemic animals. These data suggest that HIF-1 likely participates in the fetal myocardial response to anemia by coordinating an increase in gene expressions that promote capillary <em>growth</em> and anaerobic metabolism. However, <em>factors</em> other than HIF-1 also appear important in the regulation of these genes. We speculate that the return of mRNA levels of angiogenic and glycolytic enzymes toward control levels in the 7-day anemic fetus is explained by a significantly increased resting myocardial blood flow, resulting from coronary <em>vascular</em> <em>growth</em> and increased coronary conductance, and a return to a state of adequate oxygen and nutrient delivery, obviating the need for enhanced transcription of genes encoding angiogenic and glycolytic enzymes.

BACKGROUND

One of the most studied pro-angiogenic factors involved in the development of colorectal cancer is the vascular endothelial growth factor (VEGF). The small molecule tyrosine kinase inhibitor semaxanib (SU5416) is one of the several agents targeting the VEGF signaling pathway, and its development centered mostly in the treatment of colorectal cancer.

METHODS

We designed and conducted an NCI-sponsored trial to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of semaxanib given twice weekly in combination with weekly irinotecan in patients with advanced colorectal cancer who had failed at least one prior treatment. The irinotecan dose was fixed at 125 mg/m(2) given weekly for 4 weeks followed by 2 weeks of rest. Patients with prior pelvic irradiation received a reduced dose of 100 mg/m(2). The semaxanib dose was escalated, going from 85 to 110 mg/m(2) and finally to 145 mg/m(2).

RESULTS

Ten patients were treated in our study and all were evaluable for toxicity. There were no drug-related Grade 4 toxicities. There was one episode of Grade 3 headache and one episode of Grade 3 vomiting. The most common Grades 1 and 2 toxicities included diarrhea, abdominal cramping, anemia and nausea. Nine patients completed at least one 6 week cycle of treatment and were considered evaluable for response. Among those nine, two had a partial response, three had stable disease and four had progressive disease after the first cycle.

CONCLUSIONS

Both irinotecan and semaxanib could be given at their full single-agent recommended doses without significant toxicity, and the combination showed signs of clinical activity. However, owing to discouraging results from Phase III trials, it is unlikely that this combination will be further explored.

BACKGROUND

Angiogenesis is of crucial importance for tumor growth and development of metastases. Vascular endothelial growth factor (VEGF) has a potent angiogenic activity and mutations of the p53 gene has been thought to upregulate VEGF. The purpose of our study was to evaluate the prognostic significance of these tumor biomarkers for angiogenesis relative to the information derived from established clinicopathological parameters in gastric cancer.

METHODS

In this study, we conducted an immunohistochemical investigation of VEGF and p53 expression in 145 tissue samples obtained from gastric cancer patients undergoing curative surgical treatment. To evaluate angiogenesis, microvessel density (MVD) was counted by staining endothelial cells immunohistochemically using anti-CD34 monoclonal antibody.

RESULTS

High MVD was significantly associated with depth of tumor invasion and distant metastasis (p = 0.004, 0.021, respectively). Moreover, overall survival for patients with high MVD were significantly lower than that of low MVD (p = 0.048). Positive expression of VEGF correlated significantly with lymph node and distant metastasis (p = 0.040, 0.048, respectively). However, no significant correlation was found between p53 expression and various clinicopathological parameters. VEGF positive tumors showed a higher MVD than VEGF negative tumors (p = 0.028). The expression of p53 did not correlate with VEGF expression. Also, the relationship between the status of p53 expression and MVD had not statistically significant differences. In the multivariate analysis, status of VEGF, p53 expression and MVD were not an independent prognostic factor.

CONCLUSIONS

VEGF seems to be an important, clinically relevant inducer of angiogenesis and angiogenesis assessed by the MVD may be a useful marker for predicting metastasis in gastric cancer. However, further studies are warranted to clarify the impact of p53 on the angiogenesis and the prognostic significance of angiogenesis in gastric cancer.

BACKGROUND

It was previously shown that human adipose-derived stromal cell (hADSC)-conditioned medium (CM) promotes wound healing. An essential part of the wound healing process is neovascularization in the wound bed.

METHODS

We hypothesized that CM prepared from hADSCs cultured as spheroids in three-dimensional suspension bioreactors (spheroid CM) would contain much higher concentrations of angiogenic growth factors secreted by hADSCs, induce a higher extent of neovascularization in the wound bed, and improve wound healing as compared with CM prepared by conventional monolayer culture (monolayer CM).

RESULTS

The concentrations of angiogenic growth factors (i.e., vascular endothelial growth factor, basic fibroblast growth factor, and hepatocyte growth factor) in spheroid CM were 20- to 145-fold higher than those in monolayer CM. Either fresh medium, monolayer CM, or spheroid CM was administered to full-thickness wounds created on the dorsal aspects of athymic mice. The monolayer CM promoted wound healing as compared with fresh medium or no treatment. Importantly, wound closure was faster, and dermal and epidermal regeneration was improved in the spheroid CM-treated mice compared with that in the monolayer CM-treated mice.

CONCLUSIONS

The improved wound healing by spheroid CM may be attributed, at least in part, to enhanced neovascularization in the wound beds. The spheroid-based CM approach showed potential as a therapy for skin wound repair.

BACKGROUND

Insulin-like growth factors (IGFs) are important mitogens and are involved in normal and malignant cellular proliferation. IGFs and IGF binding proteins (IGFBPs) regulate the prostatic cell growth and reduction/blocking of IGFs has been suggested to be of therapeutic value in prostate cancer. beta,beta-dimethyl acryl shikonin, an extract from the roots of plant Arnebia nobilis has been shown to have anticancer properties but was found to be toxic. Subsequently, several analogoues of beta,beta-dimethyl acryloyl shikonin were synthesized and one of them shikonin analogue 93/637 (SA) was significantly less toxic compared to beta,beta-dimethyl acryloyl shikonin.

METHODS

We have investigated the effect of SA on prostate cancer cell (DU 145, LNCaP and PC-3) growth and expression of IGFs (IGF-I, IGF-II and IGF-I receptor (IGF-IR)), IGFBP-3 and vascular endothelial growth factor (VEGF).

RESULTS

SA had growth inhibitory effect on PC-3 cells in a dose dependent manner. It also showed slight inhibitory effect on the growth of DU 145 and LNCaP cells at low doses ranging from 250 nM to 1 microM and has moderate inhibitory effect at concentrations 2.5 microM and above. Lactate dehydrogenase (LDH) activity assays indicated cellular damage, only at higher concentrations of SA that are greater than 1 microM. Gene expression studies by RT-PCR have demonstrated a decrease in mRNAs of IGF-II in DU 145, IGF-I, and IGF-IR in LNCaP, and IGF-II and VEGF in PC-3 cells and an increase in IGFBP-3 in both DU 145 and PC-3 cells by treatment with SA.

CONCLUSIONS

The results demonstrate the inhibitory effect of SA on cellular growth and IGFs specifically in PC-3 cells and suggest a potential therapeutic use in treatment of prostate cancer.

Angiogenesis plays a central role in a variety of physiologic and pathologic disease states. Because the <em>growth</em> and metastasis of malignant neoplasms require the presence of an adequate blood supply, pharmacologic inhibition of tumor-induced angiogenesis represents a promising target for antineoplastic therapy. A number of approaches to such inhibition are therefore under active investigation. <em>Vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> (VEGF) and its receptor VEGFR-2 are among the best characterized of the various key elements in benign and neoplastic angiogenesis. In 1997, clinical trials were initiated to evaluate an anti-VEGF monoclonal antibody and a VEGFR-2 antagonist as therapy for patients with different types of solid tumors and hematologic neoplasms. Dose selection for these cytostatic agents requires translation from preclinical models, as these agents are likely to require chronic dosing at an optimal biological dose, rather than a maximally tolerated dose. For example, SU5416, a novel small-molecule inhibitor of VEGFR-2, administered at <em>145</em> mg/m2 intravenously twice weekly, is well tolerated and achieves the concentration levels required to inhibit <em>endothelial</em> cell proliferation in preclinical models. Because the mechanism of action of angiogenesis inhibitors is complementary to that of classic cytotoxic chemotherapy, preclinical models and subsequent clinical trials frequently explore combinations of these agents with cytotoxic chemotherapy, hoping to achieve additive or synergistic antitumor activity. It is hoped that the combination of angiogenesis inhibitors with cytotoxic chemotherapeutic agents will significantly improve survival and quality of life for cancer patients. As a result of favorable results from Phase 1 and 2 studies, randomized, multicenter clinical investigations of angiogenesis inhibitors are ongoing.

BACKGROUND

Systemic sclerosis (SSc) and mixed connective tissue disease (MCTD) are chronic immune-mediated disorders complicated by vascular organ damage. The aim of this study was to examine the serum levels of the markers of neoangiogenesis: endostatin and vascular endothelial growth factor (VEGF), in our unselected cohorts of SSc and MCTD.

METHODS

Sera of SSc patients (N = 298) and MCTD patients (N = 162) from two longitudinal Norwegian cohorts were included. Blood donors were included as controls (N = 100). Circulating VEGF and endostatin were analyzed by enzyme immunoassay.

RESULTS

Mean endostatin levels were increased in SSc patients 93.7 (37) ng/ml (P < .001) and MCTD patients 83.2 (25) ng/ml (P < .001) compared to controls 65.1 (12) ng/ml. Median VEGF levels were elevated in SSc patients 209.0 (202) pg/ml compared to MCTD patients 181.3 (175) pg/ml (P = .017) and controls 150.0 (145) pg/ml (P < .001). Multivariable analysis of SSc subsets showed that pulmonary arterial hypertension (coefficient 15.7, 95 % CI: 2.2-29.2, P = .023) and scleroderma renal crisis (coefficient 77.6, 95 % CI: 59.3-100.0, P < .001) were associated with elevated endostatin levels. Multivariable analyses of MCTD subsets showed that digital ulcers were associated with elevated endostatin levels (coefficient 10.5, 95 % CI: 3.2-17.8, P = .005). The risk of death increased by 1.6 per SD endostatin increase (95 % CI: 1.2-2.1, P = .001) in the SSc cohort and by 1.6 per SD endostatin increase (95 % CI: 1.0-2.4, P = .041) in the MCTD cohort after adjustments to known risk factors.

CONCLUSIONS

Endostatin levels were elevated in patients with SSc and MCTD, particularly SSc patients with pulmonary arterial hypertension and scleroderma renal crisis, and MCTD patients with digital ulcers. Elevated endostatin levels were also associated with increased all-cause mortality during follow-up in both groups of patients. We propose that endostatin might indicate the degree of vascular injury in SSc and MCTD patients.

<AbstractText>To summarize the rates of atrophy, risk <em>factors</em>, and atrophy-associated visual outcomes in patients with neo<em>vascular</em> age-related macular degeneration (nAMD) who received anti-<em>vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> (VEGF) treatment for macular neo<em>vascular</em>ization (MNV).</AbstractText><AbstractText>Age-related macular degeneration is a leading cause of vision loss worldwide, and VEGF inhibitors are the primary treatment for nAMD. However, atrophy is observed frequently in eyes treated with anti-VEGF therapy, prompting questions regarding a causative role for these therapies in atrophy development.</AbstractText><AbstractText>PubMed was searched for articles published in the past 5 years (January 1, 2014, through January 10, 2019). Studies including atrophy outcome(s) in patients with age-related macular degeneration who received anti-VEGF treatment were included. Review articles, retrospective studies, case reports or studies, preclinical studies, prevalence data reports, and non-English studies were excluded. Randomization was not required.</AbstractText><AbstractText>Overall, <em>145</em> studies were identified; 29 publications were included, with cohorts ranging from 8 to 1185 eyes. Imaging methods used to assess atrophy varied across studies. All studies confirmed the occurrence of atrophy, and when available, longitudinal data from the included studies demonstrated an increase in atrophy incidence over time. Key risk <em>factors</em> or phenotypes associated with atrophy were fellow eye atrophy, reticular pseudodrusen, increased injections, and type 3 lesion. In addition, visual acuity loss was noted with foveal atrophy.</AbstractText><AbstractText>All studies demonstrated that atrophy occurs in the context of MNV treated with anti-VEGF therapy; however, it is not clear whether anti-VEGF treatment is causative of atrophy versus being associated with atrophy development. The included studies were not designed or powered to assess atrophy as a primary outcome. In addition, it is difficult to determine whether prognostic <em>factors</em> directly affect atrophy. Furthermore, patient populations in clinical trials do not necessarily represent real-world patients. Although phenotypes and risk <em>factors</em> may help to identify those at greater risk of atrophy developing, it is important to recognize that adequately treating exudative MNV remains the best option to optimize vision outcomes in patients with nAMD, particularly given the risk of vision loss with undertreatment observed in the real world.</AbstractText>

The tumor microenvironment and proinflammatory signals significantly alter glycosylation of cell-surface proteins on <em>endothelial</em> cells. By altering the <i>N</i>-glycosylation machinery in the endoplasmic reticulum and Golgi, proinflammatory cytokines promote the modification of <em>endothelial</em> glycoproteins such as <em>vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> receptor 2 (VEGFR2) with sialic acid-capped <i>N</i>-glycans. VEGFR2 is a highly <i>N-</i>glycosylated receptor tyrosine kinase involved in pro-angiogenic signaling in physiological and pathological contexts, including cancer. Here, using glycoside hydrolase and kinase assays and immunoprecipitation and MS-based analyses, we demonstrate that <i>N</i>-linked glycans at the Asn-247 site in VEGFR2 hinder VEGF ligand-mediated receptor activation and signaling in <em>endothelial</em> cells. We provide evidence that cell surface-associated VEGFR2 displays sialylated <i>N</i>-glycans at Asn-247 and, in contrast, that the nearby sites Asn-<em>145</em> and Asn-160 contain lower levels of sialylated <i>N</i>-glycans and higher levels of high-mannose <i>N</i>-glycans, respectively. Furthermore, we report that VEGFR2 Asn-247-linked glycans capped with sialic acid oppose ligand-mediated VEGFR2 activation, whereas the uncapped asialo-glycans favor activation of this receptor. We propose that <i>N</i>-glycosylation, specifically the capping of <i>N-</i>glycans at Asn-247 by sialic acid, tunes ligand-dependent activation and signaling of VEGFR2 in <em>endothelial</em> cells.

OBJECTIVE

This study was designed to observe whether estrogen can enhance the proliferation of hemangioma vascular endothelial cells (VECs) and, if so, the possible inhibiting effect of tamoxifen against estrogen.

METHODS

Two skin hemangiomas with positive estrogen receptor staining from 2 infants were used for VECs culture. Based on different culture conditions and treatment, the subcultured VECs of passage 3 derived from a hemangioma were divided into 5 groups: group 1, control without endothelial cell growth supplement (ECGS) in medium; group 2, estradiol (E2) without ECGS; group 3, control with ECGS in medium; group 4, E2 with ECGS; group 5, E2 and 4OH-tamoxifen with ECGS. Cell counts and 3H-TdR incorporations were determined on culture days 3, 6, and 9. VECs from the other hemangioma were divided into 2 groups: group 3, control with ECGS in medium; group 4, E2 with ECGS.

RESULTS

At the end of the 9-day study, the cell counts (x10(4)/mL) of the 5 groups were 6.31+/-1.24, 6.52+/-1.08, 15.62+/-1.88, 36.77+/-3.96, and 6.88+/-1.20, respectively. 3H-TdR incorporations (cpm) were 511+/-127, 538+/-26, 1,350+/-67, 2,729+/-145, and 575+/-64, respectively. The results of the other hemangioma were similar to those of the first one. Our data showed that without ECGS in medium, E2 had no effect on the proliferation of VECs (group 1 v group 2, P>.05); with ECGS in medium, E2 yielded a 2-fold increase in the proliferation of VECs (group 3 v group 4, P<.01); when 4OH-tamoxifen was added, the proliferation of VECs was suppressed dramatically (group 4 vgroup 5, P<.01).

CONCLUSIONS

Estrogen in vitro can promote the proliferation of hemangioma VECs. This promoting effect of estrogen may depend on certain growth factors, which can be inhibited by tamoxifen.

The identification of agents with antiproliferative activity against <em>endothelial</em> cells has significant value for the treatment of many angiogenesis-dependent pathologies. Herein, we describe the discovery of a series of thalidomide analogues possessing inhibitory effects against both <em>endothelial</em> and prostate cancer cells. More specifically, several analogues exhibited low micromolar to mid-nanomolar potency in the inhibition of human micro<em>vascular</em> <em>endothelial</em> cell (HMEC) proliferation, both in the presence and absence of <em>vascular</em> <em>endothelial</em> <em>growth</em> <em>factor</em> (VEGF), with the tetrafluorophthalimido class of compounds demonstrating the greatest potency. Additionally, all the compounds were screened against two different androgen independent prostate cancer cell lines (PC-3 and DU-<em>145</em>). Again, the tetrafluorophthalimido analogues exhibited the greatest effect with GI(50) values in the low micromolar range. Thalidomide was found to demonstrate selective inhibition of androgen receptor positive LNCaP prostate cancer cells. Furthermore, we showed that, as an example, tetrafluorophthalimido analogue 19 was able to completely inhibit the prostate specific antigen (PSA) secretion by the LNCaP cell line, while thalidomide demonstrated a 70% inhibition. We have also demonstrated that a correlation exists between HMEC and prostate cancer cell proliferation for this structural class. Altogether, our study suggests that these analogues may serve as promising leads for the development of agents that target both androgen dependent and independent prostate cancer and blood vessel <em>growth</em>.