Angiogenesis In HUVEC Cells Research Articles

Transcription Factor MAZ Potentiates the Upregulated NEIL3-mediated Aerobic Glycolysis, thereby Promoting Angiogenesis in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is characterized by high vascularity and notable abnormality of blood vessels, where angiogenesis is a key process in tumorigenesis and metastasis. The main functions of Nei Like DNA Glycosylase 3 (NEIL3) include DNA alcoholization repair, immune response regulation, nervous system development and function, and DNA damage signal transduction. However, the underlying mechanism of high expression NEIL3 in the development and progression of HCC and whether the absence or silencing of NEIL3 inhibits the development of cancer remain unclear. Therefore, a deeper understanding of the mechanisms by which increased NEIL3 expression promotes cancer development is needed. Expression of NEIL3 and its upstream transcription factor MAZ in HCC tumor tissues was analyzed in bioinformatics efforts, while validation was done by qRT-PCR and western blot in HCC cell lines. The migration and tube formation capacity of HUVEC cells were analyzed by Transwell and tube formation assays. Glycolytic capacity was analyzed by extracellular acidification rate, glucose uptake, and lactate production levels. Chromatin immunoprecipitation (ChIP) and dual-luciferase reporter gene assays were utilized to investigate specific interactions between MAZ and NEIL3. NEIL3 and MAZ were substantially upregulated in HCC tissues and cells. NEIL3 was involved in modulating the glycolysis pathway, suppression of which reversed the stimulative impact of NEIL3 overexpression on migration and angiogenesis in HUVEC cells. MAZ bound to the promoter of NEIL3 to facilitate NEIL3 transcription. Silencing MAZ reduced NEIL3 expression and suppressed the glycolysis pathway, HUVEC cell migration, and angiogenesis. MAZ potentiated the upregulated NEIL3-mediated glycolysis pathway and HCC angiogenesis. This study provided a rationale for the MAZ/NEIL3/glycolysis pathway as a possible option for anti-angiogenesis therapy in HCC.

Exosomes Derived from Antler Mesenchymal Stem Cells Promote Wound Healing by miR-21-5p/STAT3 Axis.

Deer antlers, unique among mammalian organs for their ability to regenerate annually without scar formation, provide an innovative model for regenerative medicine. This study explored the potential of exosomes derived from antler mesenchymal stem cells (AMSC-Exo) to enhance skin wound healing. We explored the proliferation, migration and angiogenesis effects of AMSC-Exo on HaCaT cells and HUVEC cells. To investigate the skin repairing effect of AMSC-Exo, we established a full-thickness skin injury mouse model. Then the skin thickness, the epidermis, collagen fibers, CD31 and collagen expressions were tested by H&E staining, Masson's trichrome staining and immunofluorescence experiments. MiRNA omics analysis was conducted to explore the mechanism of AMSC-Exo in skin repairing. AMSC-Exo stimulated the proliferation and migration of HaCaT cells, accelerated the migration and angiogenesis of HUVEC cells. In the mouse skin injury model, AMSC-Exo stimulated angiogenesis and regulated the extracellular matrix by facilitating the conversion of collagen type III to collagen type I, restoring epidermal thickness to normal state without aberrant hyperplasia. Notably, AMSC-Exo enhanced the quality of wound healing with increased vascularization and reduced scar formation. MiRNAs in AMSC-Exo, especially through the miR-21-5p/STAT3 signaling pathway, played a crucial role in these processes. This study underscores the efficacy of AMSC-Exo in treating skin wounds, suggesting a new approach for enhancing skin repair and regeneration.

Mechanism of LEF1-AS1 regulating HUVEC cells by targeting miR-489-3p/S100A11 axis.

The venous malformation is the most common congenital vascular malformation and exhibits the characteristics of local invasion and lifelong progressive development. Long noncoding RNA (lncRNA) regulates endothelial cells, vascular smooth muscle cells, macrophages, vascular inflammation, and metabolism and also affects the development of venous malformations. This study aimed to elucidate the role of the lncRNA LEF1-AS1 in the development of venous malformations and examine the interaction among LEF1-AS1, miR-489-3p, and S100A11 in HUVEC cells. Venous malformation tissues, corresponding normal venous tissues, and HUVEC cells were used. Agilent human lncRNA microarray gene chip was used to screen differential genes, RNA expression was detected using quantitative reverse transcription PCR, and protein expression was detected using Western blotting. The proliferation, migration, and angiogenesis of HUVEC cells were assessed using CCK8, transwell, and in vitro angiogenesis tests. A total of 1,651 lncRNAs were screened using gene chip analysis, of which 1015 were upregulated and 636 were downregulated. The lncRNA LEF1-AS1 was upregulated with an obvious difference multiple, and the fold-change value was 11.03273. The results of the analysis performed using the StarBase bioinformatics prediction website showed that LEF1-AS1 and miR-489-3p possessed complementary binding sites and that miR-489-3p and S100A11 also had complementary binding sites. The findings of tissue experiments revealed that the expressions of LEF1-AS1 and S100A11 were higher in tissues with venous malformations than in normal tissues, whereas the expression of miR-489-3p was lower in venous malformations than in normal tissues. Cell culture experiments indicated that LEF1-AS1 promoted the proliferation, migration, and angiogenesis of HUVEC cells. In these cells, LEF1-AS1 targeted miR-489-3p, which in turn targeted S100A11. LEF1-AS1 acted as a competitive endogenous RNA and promoted the expression of S100A11 by competitively binding to miR-489-3p and enhancing the proliferation, migration, and angiogenesis of HUVEC cells. Thus, LEF1-AS1 participated in the occurrence and development of venous malformation. The expression of LEF1-AS1 was upregulated in venous malformations, and the expression of S100A11 was increased by the adsorption of miR-489-3p to venous endothelial cells, thus enhancing the proliferation, migration, and angiogenesis of HUVEC cells. In conclusion, LEF1-AS1 is involved in the occurrence and development of venous malformations by regulating the miR-489-3p/S100A11 axis, which provides valuable insights into the pathogenesis of this disease and opens new avenues for its treatment.

Abstract P2-22-04: Functional effect of miR-1307-3p on breast cancer progression

Abstract Background: MiRNAs are non-coding RNA molecules and its function is the regulation of gene expression. In cancer, the deregulation of miRNAs allows them to act as oncogenes or tumor suppressors. From an analysis of the expression of miRNAs in breast cancer (BC) in The Cancer Genome Atlas (TCGA), it was identified that miR-1307-3p is significantly overexpressed in the tumor tissue compared to healthy tissue from patients. So far, in BC, it has only been reported that this miRNA inhibits SMYD4 and that it is involved in resistance to cisplatin through its effect on Mdm4. In this project we propose to identify the role of miR-1307-3p in proliferation, migration, invasion, angiogenesis, and possible targets involved in these processes in BC cells. Methods: RT-qPCR was used to evaluate basal levels of miR-1307-3p in the BC cell lines MDA-MB-231 and MCF-7, and the human epithelial breast MCF-10A cells. Later, we determined the effect of miR-1307-3p on proliferation, migration, and invasion in MDA-MB-231 and MCF-7, and angiogenesis in the HUVEC endothelial cells. All assays were carried out using the miR-1307-3p inhibitor. Finally, nine miRNA-target prediction databases were analyzed to identify potential miR-1307-3p target genes, and their expression was analyzed by RT-qPCR in a designed 384-well plate. Results: We found that miR-1307-3p is overexpressed in MDA-MB-231 and MCF-7, compared to MCF-10A cells. We also identified that transfection with the miR-1307-3p inhibitor causes a significant decrease in the processes of proliferation, migration, invasion, and angiogenesis, when compared with untreated or negative control transfected cells. For its part, prediction databases analysis allowed us to identify 19 potential targets of miR-1307-3p. Finally, by RT-qPCR, the overexpression of 3 and the downregulation of 2 genes were confirmed. Conclusions: MiR-1307-3p is overexpressed in BC cells. Furthermore, miR-1307-3p induces the processes of proliferation, migration and invasion in BC cells, and angiogenesis in HUVEC cells. These observations suggest that miR-1307-3p can acts as an onco-miRNA. In addition, the expression of 5 of the predicted target genes were altered by miR-1307-3p inhibitor. Further analysis to validate the implication of this miR-1307-3p targets are needed to understand its importance in BC. Citation Format: José Roberto Estupiñan Jimenez, Valeria Villarreal-García, Ricardo Noriega, Recep Bayraktar, Diana Reséndez-Pérez, Cristina Rodríguez-Padilla, José Manuel Vázquez-Guillén, Fermín Mar-Aguilar, Gabriel Lopez-Berestein, Pablo E. Vivas-Mejía, Vianey Gonzalez-Villasana. Functional effect of miR-1307-3p on breast cancer progression [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-22-04.

Phenolic Extract(s) from Wild Blueberries promote(s) wound healing via vascularization

Wounds occur in over 15 million people with approximately $60 billion spent annually on wound care. Deficient vascularization is a significant factor that promotes chronic and non‐healing wounds, ultimately resulting in amputation. Currently, most clinical wound treatments are antibiotics for infection control. Therefore, chronic wounds such as diabetic foot ulcers, ischemic limbs, and pressure ulcers lack treatments for healing. Our lab reported that phenolic extracts (PE) from wild blueberries (WB) promote angiogenesis in HUVEC cells via cell migration, angiogenesis, and VEGF/P13K/AKT pathway. However, the in vivoeffect is still unknown. To investigate the in vivo pathways of PE from WB on vascularized wound healing, we extracted PE from WB by Folin‐Ciocalteu method, and incorporated them into a serum [hyaluronic (HA) gel] and a cream carrier. We grouped fifty‐six Sprague‐Dawley rats into seven groups as follows: Group1 as Control (nothing applied on the skin); Group 2 as the cream base, without the PE; Group 3 as the HA gel base, without PE; Group 4 as the HA gel base with 500 μg/ml of the PE; Group 5 as the cream base with 500 μg/ml of PE; Group 6 as the HA gel base with PE at 1000 μg/ml; and Group7 as the cream base with PE at 1000 μg/ml. We created dorsal surgical wounds on each rat and treated them accordingly for six days. Photographs were taken daily to assess wound closure. Percentage wound closure was determined using ImageJ. Thereafter, the tissues were excised and stained with H&E, visualized and quantified under light microscope for proliferating cells associated with vascular wound closure. We observed 12% increase in wound closure and significant increase in endothelial cells on the wound area with 500 μg/ml of PE in serum (HA gel) treatment when compared to the control without treatment. The results support the potential effect of PE to promote vascularized wound healing. Frozen tissues are currently being analyzed for genes and proteins associated with vascularization. This project is innovative because it provides new insights into the metabolomic pathways of PE treatment in rats used as a wound healing model. Results of this project may be beneficial to patients with chronic wounds promoting vascularization and wound healing, with all natural, inexpensive, no side effect wound healing products, using Phenolic extracted from WB.

Connexin46 Expression Enhances Cancer Stem Cell and Epithelial-to-Mesenchymal Transition Characteristics of Human Breast Cancer MCF-7 Cells.

Connexins (Cxs) are a family of proteins that form two different types of ion channels: hemichannels and gap junction channels. These channels participate in cellular communication, enabling them to share information and act as a synchronized syncytium. This cellular communication has been considered a strong tumor suppressor, but it is now recognized that some type of Cxs can be pro-tumorigenic. For example, Cx46 expression is increased in human breast cancer samples and correlates with cancer stem cell (CSC) characteristics in human glioma. Thus, we explored whether Cx46 and glioma cells, can set up CSC and epithelial-to-mesenchymal transition (EMT) properties in a breast cancer cell line. To this end, we transfected MCF-7 cells with Cx46 attached to a green fluorescent protein (Cx46GFP), and we determined how its expression orchestrates both the gene-expression and functional changes associated with CSC and EMT. We observed that Cx46GFP increased Sox2, Nanog, and OCT4 mRNA levels associated with a high capacity to form monoclonal colonies and tumorspheres. Similarly, Cx46GFP increased the mRNA levels of n-cadherin, Vimentin, Snail and Zeb1 to a higher migratory and invasive capacity. Furthermore, Cx46GFP transfected in MCF-7 cells induced the release of higher amounts of VEGF, which promoted angiogenesis in HUVEC cells. We demonstrated for the first time that Cx46 modulates CSC and EMT properties in breast cancer cells and thus could be relevant in the design of future cancer therapies.

Network analysis and the impact of Aflibercept on specific mediators of angiogenesis in HUVEC cells.

Angiogenesis, inflammation and endothelial cells’ migration and proliferation exert fundamental roles in different diseases. However, more studies are needed to identify key proteins and pathways involved in these processes. Aflibercept has received the approval of the US Food and Drug Administration (FDA) for the treatment of wet AMD and colorectal cancer. Moreover, the effect of Aflibercept on VEGFR2 downstream signalling pathways has not been investigated yet. Here, we integrated text mining data, protein‐protein interaction networks and multi‐experiment microarray data to specify candidate genes that are involved in VEGFA/VEGFR2 signalling pathways. Network analysis of candidate genes determined the importance of the nominated genes via different centrality parameters. Thereupon, several genes—with the highest centrality indexes—were recruited to investigate the impact of Aflibercept on their expression pattern in HUVEC cells. Real‐time PCR was performed, and relative expression of the specific genes revealed that Aflibercept modulated angiogenic process by VEGF/PI3KA/AKT/mTOR axis, invasion by MMP14/MMP9 axis and inflammation‐related angiogenesis by IL‐6‐STAT3 axis. Data showed Aflibercept simultaneously affected these processes and determined the nominated axes that had been affected by the drug. Furthermore, integrating the results of Aflibercept on expression of candidate genes with the current network analysis suggested that resistance against the Aflibercept effect is a plausible process in HUVEC cells.

SFLT01 modulates invasion and metastasis in prostate cancer DU145 cells by inhibition of VEGF/GRP78/MMP2&9 axis

BackgroundAbout 90% of cancer-related deaths are due to metastasis of cancer cells, and angiogenesis is a critical step in this process. sFLT01 is a novel fusion protein and a dual-targeting agent that neutralizes both VEGF and PlGF proangiogenic activities. GRP78 dual effect in tumor growth and angiogenesis could be activated under VEGF stimulation. The current study was designed to investigate the inhibitory impact of sFLT01 protein on VEGF/GRP78 axis. To this point, sFLT01 construct was synthesized, recombinant plasmid was expressed in eukaryotic host cells, sFLT01-HisTag protein was extracted and analyzed. The functional activity of sFLT01 on VEGF-enhanced tube formation and angiogenesis of HUVEC cells were examined. Eventually, the inhibitory impact of sFLT01 on growth, invasiveness, and migration of human prostate cancer cell line, DU145, was assessed. Real-time PCR evaluated the level of GRP78 and its effect on the downstream factors; matrix metallopeptidase proteins 2&9 (MMP2&9) along with tissue inhibitor of metalloproteinase proteins1&2 (TIMP1&2) under sFLT01 stimulation.ResultsAccording to the data, sFLT01 protein showed modulatory impact on proliferation, invasion, and migration of DU145 cells along with the potential of HUVECs angiogenesis. Real-Time PCR analysis depicted a significant downregulation in GRP78, MMP2 and MMP9 transcripts’ levels, and a subsequent elevation of TIMP1 and TIMP2 expression under sFLT01 stimulation was detected.ConclusionOverall, these data indicated that the inhibitory impact of sFLT01 on cancer cells growth and invasiveness could be mediated through the modulation of VEGF/GRP78/MMP2&9 axis and activation of TIMPs.

Exosome-derived miR-181a promotes angiogenesis of glioma

Objective: To explore the effect of exosome-derived miR-181a on angiogenesis and tumor progression in gliomas.Methods: 83 cases of glioma tissues and 13 cases of peritumoral tissues resected in the Second Affiliated Hospital of Hainan Medical University from August 2017 to December 2019, glioma cells U87, A172, U251, LN229, U373 and microglial cell line HM, were selected to detect the expression of miR-181a in tumor tissues and cells by qPCR method. Glioma U373 cells with miR-181a overexpression or knockdown were constructed, and exosomes were isolated and identified. The effects of exsome-derived miR-181a on angiogenesis of HUVEC cells were investigated by tubule formation and chicken chorioallantoic membrane assay in vitro. Nude mice bearing U373 cell transplanted xenograft was constructed to observe the effect of exsome-derived miR-181a on angiogenesis and tumor growth in vivo. Results: The expression of miR-181a in glioma tissues and cells was significantly higher than that in normal tissues and normal glial HM cells (all P<0.01). The exsome-derived miR-181a could significantly promote the tubule formation of HUVEC cells (P<0.01) and the angiogenesis of chicken chorioallantoic membrane (all P<0.01). In vivo experiments showed that the growth of xenografts was promoted (P<0.05) and the amount of angiogenesis in the tumor tissues was increased in the nude mice after being transfused with exsome-derived miR-181a (P<0.01). Conclusion: miR-181a plays an important role in promoting angiogenesis of gliomas and may be a potential target for diagnosis and treatment of gliomas.

The mechanism of lncRNA‐CRNDE in regulating tumour‐associated macrophage M2 polarization and promoting tumour angiogenesis

M2 macrophages can promote liver cancer metastasis by promoting tumour angiogenesis; however, the mechanism underlying macrophage polarization has not been completely revealed. In this study, we mainly explored the mechanism underlying long non‐coding RNA‐CRNDE (lncRNA‐CRNDE) in regulating M2 macrophage polarization and promoting liver cancer angiogenesis. The expression of CRNDE was up‐regulated or down‐regulated in THP‐1 cells (CRNDE‐/‐‐THP‐1 cells and pcDNA3.1‐CRNDE‐THP‐1). THP‐1 cells were co‐cultured with liver cancer cell line H22, and M2 polarization was induced in THP‐1 by IL‐4/13 to simulate tumour‐induced macrophage polarization. As a result, after CRNDE overexpression, THP‐1 cell viability was up‐regulated, the expression of M2 membrane marker CD163 was up‐regulated, and the proportion of F4/80 + CD163+ cells was also up‐regulated. ELISA assay showed that the expression of M2 markers (including TGF‐β1 and IL‐10) and chemokines (including CCl22 and CCL22) was up‐regulated, and the expression of key signals (including STAT6, JAK‐1, p‐AKT1, and Arg‐1) was also up‐regulated, which were significantly different compared with the control group (Con). In addition, the intervention effect of CRNDE on THP‐1 was consistent between co‐culture with H22 cells and IL‐4/13 induction assay. The induced M2 THP‐1 cells were co‐cultured with HUVEC. As a result, THP‐1 cells with CRNDE overexpression can promote the migration and angiogenesis of HUVEC cells in vitro and simultaneously up‐regulate the expression of Notch1, Dll4 and VEGFR2, indicating that THP‐1 M2 polarization induced by CRNDE could further promote angiogenesis. The H22 cell tumour‐bearing mouse model was constructed, followed by injection of CRNDE anti‐oligosense nucleotides and overexpression plasmids to interfere CRNDE expression in tumour‐bearing tissues. Consequently, down‐regulation of CRNDE could down‐regulate tumour volume, simultaneously down‐regulate the expression of CD163 and CD31 in tissues, decrease the expression of key proteins (including JAK‐1, STAT‐6, p‐STAT6 and p‐AKT1), and down‐regulate the expression of key angiogenesis‐related proteins (including VEGF, Notch1, Dll4 and VEGFR2). In this study, we found that CENDE could indirectly regulate tumour angiogenesis by promoting M2 polarization of macrophages, which is also one of the mechanisms of microenvironmental immune regulation in liver cancer.

Abstract 2528: Tumor-derived exosomal miR-619-5p promotes tumor angiogenesis and metastasis through the inhibition of RCAN1.4

Abstract Tumor-derived exsosomes (TEXs) contain enriched miRNAs act as novel non-invasive biomarkers for cancer diagnosis, and they are involved in cancer progression. In this study, we aimed to investigate which and how exosomal miRNA affect cancer progression in non-small cell lung cancer (NSCLC). We found that the only of A549 cell-released exosomes promote an angiogenic phenotype in HUVEC cells compared to other lung cancer cell-released exosomes. Using a miRNA array and RNA sequencing approach, we identified that specific miRNAs can modulate angiogenesis in A549 cell-released exosomes. Among these miRNAs, miR-619-5p significantly induced angiogenesis in HUVEC cells. Subsequently, RCAN1.4 was identified as a target of miR-619-5p and the suppression of RCAN1.4 inhibited the angiogenesis of HUVEC cells. Furthermore, the suppression of RCAN1.4 by miR-619-5p promoted the cellular mobility and proliferation in in vitro, as well as in vivo, tumor growth and metastasis in non-small cell lung cancer (NSCLC) cells. In patients with non-small cell lung cancer (NSCLC), the level of RCAN1.4 expression was significantly lower in tumor tissues than normal lung tissues, whereas the level of miR-619-5p was a significant higher in tumor tissue than normal lung tissues. We also found that there was a significant inverse correlation between the expression of miR-619-5p and that of RCAN1.4. In addition, miR-619-5p expression was higher in exosomes isolated from plasma of patients with NSCLC than normal. Finally, hypoxia condition led to enhance the amount of miR-619-5p within NSCLC cells-derived exosomes. In conclusion, exosomal miR-619-5p promotes tumor growth and metastasis of NSCLC by regulating RCAN1.4 in endothelial and tumor cells, and it can serve as a diagnosis and prognostic indicator for NSCLC patients. Citation Format: Sang Yong Jung, Dong Ha Kim, Yong-Hee Cho, Yun Jung Choi, Seon Ye Kim, Ki Jung Sung, Chae Won Lee, Hyeon Jeong Lee, Chang-Min Choi, Jae Cheol Lee, Jin Kyung Rho. Tumor-derived exosomal miR-619-5p promotes tumor angiogenesis and metastasis through the inhibition of RCAN1.4 [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2528.

Macrophage colony stimulating factor enhances non-small cell lung cancer invasion and metastasis by promoting macrophage M2 polarization

Objective: To investigate the key cytokine which polarizes M2 macrophages and promotes invasion and metastasis in non-small cell lung cancer (NSCLC). Methods: After co-culture with A549 cells in vitro, the proportion of CD14(+) CD163(+) M2 macrophages in monocytes and macrophage colony stimulating factor (M-CSF) levels in culture supernatant were detected by flow cytometry, ELISA assay and real-time qPCR, respectively. The effects of CD14(+) CD163(+) M2 macrophages on invasion of A549 cells and angiogenesis of HUVEC cells were measured by transwell assay and tubule formation assay, respectively. The clinical and prognostic significance of M-CSF expression in NSCLC was further analyzed. Results: The percentage of CD14(+) CD163(+) M2 macrophages in monocytes and the concentration of M-CSF in the supernatant followed by co-culture was (12.03±0.46)% and (299.80±73.76)pg/ml, respectively, which were significantly higher than those in control group [(2.80±1.04)% and (43.07±11.22)pg/ml, respectively, P< 0.05]. Human recombinant M-CSF promoted M2 polarization of macrophages in vitro. M2 macrophages enhanced the invasion of A549 cells (66 cells/field vs. 26 cells/field) and the angiogenesis of HUVEC cells (22 tubes/field vs. 8 tubes/field). The mRNA expression of M-CSF in stage Ⅰ-Ⅱ patients (16.23±4.83) was significantly lower than that in stage Ⅲ-Ⅳ (53.84±16.08; P<0.05). M-CSF levels were associated with poorer overall survival and disease-free survival in NSCLC patients (P<0.05). Conclusions: Tumor-derived M-CSF can induce CD14(+) CD163(+) M2 polarization of macrophages, which can further promote the metastasis and angiogenesis of NSCLC. M-CSF could be used as a potential therapeutic target of NSCLC.

Anti-carcinogenic and anti-angiogenic properties of the extracts of Acorus calamus on gastric cancer cells.

Acorus calamus (A. calamus) has been used as a medicinal plant in Asia for its effects on digestive system for the last 2000 years. To investigate the anti-cancer activity of rhizome of A. calamus, the ethanolic and methanolic extracts and essential oil of the rhizome were prepared and their effects were assessed on human gastric cancer cell line (AGS). The viability of cells which were treated with the extracts and the essential oil was assessed by MTT assay. To evaluate the anti-angiogenic property of the extracts, in vitro tube formation assay was done. Cell cycle distribution and the expression of Oct4 and Nucleostemin, after treatments, were checked by flowcytometry and quantitative RT-PCR, respectively. Furthermore, analysis of essential oil from A.calamus was done by GC-MS. Our results showed that the growth of AGS cells was inhibited by the extracts and essential oil and the extracts inhibited the angiogenesis in HUVEC cells. Our data revealed that the extracts and essential oil of A. calamus caused G1 arrest in AGS cells and downregulation of Oct4 and NS after treatment. By GC-MS analysis, we found new compounds such as epiprezizaene, valencene and isocyclocitral in essential oil of A. All together, our results showed that the extracts of A. calamus have anti-proliferative and anti-angiogenic effects on cancer cells.

Structure–activity relationship of Garcinia xanthones analogues: Potent Hsp90 inhibitors with cytotoxicity and antiangiogenesis activity

Hsp90 has long been recognized as an attractive and crucial molecular target for cancer therapy. Gambogic acid (GA), the main active compound of Gamboge hanburyi, has been reported as a natural inhibitor of Hsp90. Here, we present the structure–activity relationship of Garcinia xanthones analogues as Hsp90 inhibitors and identify that compound 25, with a simplified skeleton, had an improved inhibitory effect toward Hsp90. Compound 25 inhibited the ATPase activity of Hsp90 with an IC50 value of 3.68±0.18μM. It also exhibited potent antiproliferative activities in some solid tumor cells. In SK-BR-3 cells with high Hsp90 expression, compound 25 induced the degradation of Hsp90 client proteins including Akt and Erk1/2 without causing the heat shock response. Additionally, compound 25 inhibited angiogenesis in HUVEC cells through Hsp90 regulation of the HIF-1α pathway. These results demonstrate that compound 25 as an Hsp90 inhibitor with a new structure could be further studied for the development of tumor therapy.

Marine bromophenol bis(2,3-dibromo-4,5-dihydroxybenzyl) ether, represses angiogenesis in HUVEC cells and in zebrafish embryos via inhibiting the VEGF signal systems.

Bis(2,3-dibromo-4,5-dihydroxybenzyl) ether (BDDE) is a bromophenol compound derived from marine algae. Our previous reports have shown that BDDE possessed anticancer activity in vitro. However, its antiangiogenesis activity and possible mechanisms remain unclear. The present study demonstrated that BDDE displayed in vitro antiangiogenesis capabilities by significantly inhibiting HUVEC cells proliferation, migration, and tube formation, without any effect on the preformed vascular tube. Western blot analysis revealed that BDDE decreased the protein level of VEGF and VEGFR but not that of EGFR, FGFR, and IGFR. In addition, BDDE inactivated the VEGF downstream signaling molecules including mTOR and Src, whereas activated Akt and ERK. Moreover, BDDE blocked subintestinal vessel formation in zebrafish embryos in vivo and showed toxicity under high concentrations of BDDE. The results of this present study indicated that BDDE, which has unique chemical structure different from current antiangiogenesis agents, could be used as a potential drug candidate for cancer prevention and therapy.

Osteocyte-induced angiogenesis via VEGF–MAPK-dependent pathways in endothelial cells

Recently, it has been suggested osteocytes control the activities of bone formation (osteoblasts) and resorption (osteoclast), indicating their important regulatory role in bone remodelling. However, to date, the role of osteocytes in controlling bone vascularisation remains unknown. Our aim was to investigate the interaction between endothelial cells and osteocytes and to explore the possible molecular mechanisms during angiogenesis. To model osteocyte/endothelial cell interactions, we co-cultured osteocyte cell line (MLOY4) with endothelial cell line (HUVECs). Co-cultures were performed in 1:1 mixture of osteocytes and endothelial cells or by using the conditioned media (CM) transfer method. Real-time cell migration of HUVECs was measured with the transwell migration assay and xCELLigence system. Expression levels of angiogenesis-related genes were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The effect of vascular endothelial growth factor (VEGF) and mitogen-activated phosphorylated kinase (MAPK) signaling were monitored by western blotting using relevant antibodies and inhibitors. During the bone formation, it was noted that osteocyte dendritic processes were closely connected to the blood vessels. The CM generated from MLOY4 cells-activated proliferation, migration, tube-like structure formation, and upregulation of angiogenic genes in endothelial cells suggesting that secretory factor(s) from osteocytes could be responsible for angiogenesis. Furthermore, we identified that VEGF secreted from MLOY4-activated VEGFR2-MAPK-ERK-signaling pathways in HUVECs. Inhibiting VEGF and/or MAPK-ERK pathways abrogated osteocyte-mediated angiogenesis in HUVEC cells. Our data suggest an important role of osteocytes in regulating angiogenesis.

α‐Tocopheryl phosphate – an activated form of vitamin E important for angiogenesis?

Vitamin E (α‐tocopherol, αT) was originally discovered as a dietary factor essential for reproduction in rats. The molecular basis for reproductive failure during vitamin E deficiency was later described to be associated with impaired formation of an extensive placental vascular network. Recently, small amounts of a novel αT derivative, alpha‐tocopheryl phosphate (αTP), have been detected in plasma and animal tissues as well as in foods. We have now assessed the effects of αT and αTP on gene expression in THP‐1 monocytes using gene arrays. The expression of the vascular endothelial growth factor (VEGF) was induced by αTP at mRNA and protein level leading to enhanced angiogenesis in HUVEC cells. Induction of VEGF by αTP was the consequence of stimulation of the PI3K/Akt signalling pathway. The treatment with αTP, but not with αT, significantly induced a VEGF‐promoter luciferase construct transfected into HEK293 cells. We propose that αT is activated by phosphorylation to αTP which may act as an active cofactor or lipid mediator influencing cellular signaling and gene expression leading, in selected tissues, to increased angiogenesis and most likely vasculogenesis. Increased VEGF expression induced by αTP may explain not only the essential effects of vitamin E on reproduction, but also increased cell survival during ischemia/reperfusion injury in brain and muscle cells. Supported by USDA Contract #58‐1950‐7‐707.

Abstract 4071: Prohibitin peptides induce apoptosis in cancer cells and inhibit angiogenesis

Abstract Prohibitin is a potential tumor suppressor protein that can repress E2F-mediated transcription and arrest cell proliferation. E2F1 binding domain of prohibitin is a coiled-coil structure and prohibitin functions through this domain to repress E2F1 transcription activity by recruiting HDAC1. The coiled- coil domain (175-217aa) by itself exhibited growth suppressive properties and showed a reduction in colony formation when transfected into breast cancer cells, T47D cells. It was shown that a synthetic peptide (42aa), designated as H1-6, corresponding to the coiled- coil domain induced apoptosis in four different human cell lines; MCF7, HAEC, BL18 and WI38 cells. Hence we decided to synthesize peptides of 14-mer (H1-2, H3-4, H5-6) and 7-mer (H2, H5) from the coiled coil domain of prohibitin and study their effect on cells. We found that each one of the prohibitin peptides (20μM) induced a marked increase in apoptosis in a panel of breast, lung and prostate cancer cell lines when compared to the control peptide (CP1). Interestingly, the peptides had no effect on breast epithelial cells, MCF10A. Treatment of MDA-MB-231 cells with 20μM of each prohibitin peptide individually reduced the invasive capability of these cells when compared to the control peptide. We also investigated their effect on angiogenesis in HUVEC cells and found that these peptides could significantly inhibit angiogenesis in vitro. In conclusion, these results suggest that these peptides could be of significant therapeutic value. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4071.