Vascular endothelial growth factor (VEGF) signaling in tumor progression

Multi-functional self-assembled nanoparticles for pVEGF-shRNA loading and anti-tumor targeted therapy

Although RNA interference (RNAi) technology shows great potential in cancer treatment, the tumor target delivery and sufficient cytosolic transport of RNAi agents are still the main obstacles for its clinical applications. Herein, we report a functional supramolecular self-assembled nanoparticle vector for RNAi agent loading and tumor target therapy. Molecular block adamantane-grafted poly(ethylene glycol) (Ad-PEG) was modified with epidermal growth factor receptor (EGFR)-specific binding ligand GE11 or pH-sensitive fusogenic peptide GALA and then used for self-assembly with cyclodextrin-grafted branched polyethylenimine (CD-PEI), adamantane-grafted polyamidoamine dendrimer (Ad-PAMAM), and plasmid DNA containing a small hairpin RNA expression cassette against vascular endothelial growth factor (VEGF) into functional DNA-loaded supramolecular nanoparticles (GE11&GALA-pshVEGF@SNPs) based on molecular recognition and charge interaction. These functional peptides facilitated the target cell binding, internalization, and endosomal escape of GE11&GALA-pshVEGF@SNPs, resulting in increased reporter gene expression and efficient targeted gene silencing. The systemic delivery of the GE11&GALA-pshVEGF@SNPs can efficiently downregulate the intratumoral VEGF protein levels, reduce blood vessel formation, and significantly inhibit A549 xenograft tumor growth. These results reveal the potential of these multifunctional self-assembled nanoparticles as a nucleic acid drug delivery system for the treatment of lung cancer.

Association between vascular endothelial growth factor receptor 2 rs11941492 C/T polymorphism and Chinese Han patients in rheumatoid arthritis

The aim of the present study was to examine the association between vascular endothelial growth factor receptor 2 (VEGFR2) rs11941492 C/T polymorphism and rheumatoid arthritis (RA) risk in an eastern Chinese Han population. We examined VEGFR2 rs11941492 C/T polymorphism in 615 RA patients and 839 controls in an East Chinese Han population. The power analysis was used for evaluating the reliability of the results. Genotyping was performed using a custom-by-design 48-Plex single nucleotide polymorphism scan Kit. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression.Our results indicated that VEGFR2 rs11941492 C/T polymorphism (TT vs CC, P = .012, OR = 0.61, 95% CI = 0.41-0.89; TT vs CT + CC, P = .017, OR = 0.63, 95% CI = 0.43-0.92) was associated with a significantly decreased risk of RA. The power analysis showed that this study had a power of 98.5% to detect the effect of rs11941492 C/T polymorphism on RA susceptibility, assuming an OR of 0.61. After stratification analysis, a decreased risk of RA was associated with VEGFR2 rs11941492 TT genotype (TT vs CC) among female patients (TT vs CC, P = .007, OR = 0.53, 95% CI = 0.33-0.84), older patients (Yr ≥55) (TT vs CC, P = .039, OR = 0.58, 95% CI = 0.35-0.97), C-reactive protein-positive patients, anti-cyclic citrullinated peptide antibody-negative patients, rheumatoid factor-positive patients (TT vs CT + CC, P = .015, OR = 0.60, 95% CI = 0.39-0.90), functional class III + IV patients, patients with a DAS28 of ≥3.20, and those with an erythrocyte sedimentation rate of <25. However, our results were obtained from only a moderate-sized sample. Studies with larger sample sizes in other ethnic populations are needed to confirm these results. The VEGFR2 rs11941492 genotype is associated with decreased susceptibility to RA.

Discovery of arylamide-5-anilinoquinazoline-8-nitro derivatives as VEGFR-2 kinase inhibitors: Synthesis, in vitro biological evaluation and molecular docking

Herein, we embarked on a structural optimization campaign aiming at the discovery of novel anticancer agents with our previously reported XL-6f as a lead compound. A library of 23 compounds has been synthesized based on the highly conserved active site of VEGFR-2. Several title compounds exhibited selective inhibitory activities against VEGFR-2, which also displayed selective anti-proliferation potency against HepG2 cell. All synthesized compounds were evaluated for anti-angiogenesis capability. Compound 7o showed the most potent anti-angiogenesis ability, the efficient cytotoxic activities (in vitro against HUVEC and HepG2 cell lines with IC₅₀ values of 0.58 and 0.23 µM, respectively). The molecular docking analysis revealed 7o is a Type-II inhibitor of VEGFR-2 kinase. In general, these results indicated these arylamide-5-anilinoquinazoline-8-nitro derivatives are promising inhibitors of VEGFR-2 for the potential treatment of anti-angiogenesis.

Vascular Endothelial Growth Factor (VEGF) in Abdominal Fluid in Dogs with Oncological and Non-Oncological Diseases

The vascular endothelial growth factor (VEGF) is a multifunctional cytokine stimulating the growth of vascular endothelial cells, survival and proliferation, inhibiting apoptosis. It is one of the most potent stimulants of vascular permeability. VEGF is found at high levels in inflammatory and tumour-associated pleural and abdominal effusions and is involved in their occurrence. In the present study, the blood plasma and abdominal fluid VEGF levels were assayed in thirty-one client-owned dogs with neoplastic and non-neoplastic diseases by means of enzyme-linked immunosorbent assay (ELISA). The VEGF concentration in abdominal fluid of dogs (n=6) with ascites was 190.70±34.35 pg/ml, in dogs (n=6) with peritonitis: 1449.81±365.42 pg/ml and in dogs (n=9) with tumour-associated effusion: 1993.13±202.56 pg/ml. Blood plasma VEGF of healthy dogs (control group, n=10) was 36.79±5.72 pg/ml, in dogs with ascites: 57.92±2.88 pg/ml, in dogs with peritonitis: 76.98±7.24 pg/ml and in dogs with tumour-associated effusion: 173.50±40.9 pg/ml. There were substantial differences between blood plasma and abdominal fluid VEGF levels.

Apatinib Mesylate in the treatment of advanced progressed lung adenocarcinoma patients with EGFR-TKI resistance -A Multicenter Randomized Trial

Few pieces of evidence have been published on the use of Apatinib Mesylate (AM) against EGFR-TKI resistance in lung adenocarcinoma (LA) patients. Here, we investigate the clinical efficacy and safety of AM in the treatment of advanced progressed epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) resistant LA patients. We conducted a double-blind, randomized controlled trial in 68 patients admitted to 18 hospitals of Anhui province in China. The efficacy and safety of AM treatment were evaluated in terms of progression-free survival (PFS), objective response rate (ORR), and disease control rate (DCR), as well as related adverse events (AE). A literature knowledge database analysis and a pathway model reconstruction were performed to decipher the relevant mechanism may be involved. Our results showed that, compared to the control group, AM presented improved efficacy in PFS (P = 0.033), ORR (P < 0.001), and DCR (P < 0.001). No significant difference was observed between case and control group in terms of AE, and no drug-related death occurred. Pathway analysis supports that Apatinib can be repurposed for the treatment of LA. Our results suggested that AM could be a potential option for advanced progressed LA patients to combat EGFR-TKI resistance.

Regulation of antitumour CD8 T-cell immunity and checkpoint blockade immunotherapy by Neuropilin-1

Neuropilin-1 (Nrp-1) is a marker for murine CD4⁺FoxP3⁺ regulatory T (Treg) cells, a subset of human CD4⁺ Treg cells, and a population of CD8⁺ T cells infiltrating certain solid tumours. However, whether Nrp-1 regulates tumour-specific CD8 T-cell responses is still unclear. Here we show that Nrp-1 defines a subset of CD8⁺ T cells displaying PD-1^hi status and infiltrating human lung cancer. Interaction of Nrp-1 with its ligand semaphorin-3A inhibits migration and tumour-specific lytic function of cytotoxic T lymphocytes. In vivo, Nrp-1⁺PD-1^hi CD8⁺ tumour-infiltrating lymphocytes (TIL) in B16F10 melanoma are enriched for tumour-reactive T cells exhibiting an exhausted state, expressing Tim-3, LAG-3 and CTLA-4 inhibitory receptors. Anti-Nrp-1 neutralising antibodies enhance the migration and cytotoxicity of Nrp-1⁺PD-1^hi CD8⁺ TIL ex vivo, while in vivo immunotherapeutic blockade of Nrp-1 synergises with anti-PD-1 to enhance CD8⁺ T-cell proliferation, cytotoxicity and tumour control. Thus, Nrp-1 could be a target for developing combined immunotherapies.

Neuropilin-1 (Nrp-1) is a marker for CD4 + regulatory T cells. Here the authors show that Nrp-1 is co-expressed with PD-1 on a subset of CD8 tumour-infiltrating T lymphocytes and inhibits T-cell migration and cytotoxicity when bound by its ligand semaphorin-3A, while blockade of Nrp-1 synergises with anti-PD-1 to promote antitumour immunity in mouse tumour models.

Inhibition of host NOX1 blocks tumor growth and enhances checkpoint inhibitor-based immunotherapy

Blocking NOX1 with the novel small molecule inhibitor GKT771 inhibits tumor growth in mice by targeting tumor lymph/angiogenesis and promoting antitumor immune cells recruitment. GKT771 emerges as a novel and promising anticancer drug worth translating into the clinics.

NADPH oxidases catalyze the production of reactive oxygen species and are involved in physio/pathological processes. NOX1 is highly expressed in colon cancer and promotes tumor growth. To investigate the efficacy of NOX1 inhibition as an anticancer strategy, tumors were grown in immunocompetent, immunodeficient, or NOX1-deficient mice and treated with the novel NOX1-selective inhibitor GKT771. GKT771 reduced tumor growth, lymph/angiogenesis, recruited proinflammatory macrophages, and natural killer T lymphocytes to the tumor microenvironment. GKT771 treatment was ineffective in immunodeficient mice bearing tumors regardless of their NOX-expressing status. Genetic ablation of host NOX1 also suppressed tumor growth. Combined treatment with the checkpoint inhibitor anti-PD1 antibody had a greater inhibitory effect on colon carcinoma growth than each compound alone. In conclusion, GKT771 suppressed tumor growth by inhibiting angiogenesis and enhancing the recruitment of immune cells. The antitumor activity of GKT771 requires an intact immune system and enhances anti-PD1 antibody activity. Based on these results, we propose blocking of NOX1 by GKT771 as a potential novel therapeutic strategy to treat colorectal cancer, particularly in combination with checkpoint inhibition.

Design, synthesis and in vitro evaluation of 6-amide-2-aryl benzoxazole/benzimidazole derivatives against tumor cells by inhibiting VEGFR-2 kinase

Herein, we have carried out a structural optimization campaign to discover the novel anti-tumor agents with our previously screened YQY-26 as the hit compound. A library of thirty-seven 6-amide-2-aryl benzoxazole/benzimidazole derivatives has been designed and synthesized based on the highly conserved active site of VEGFR-2. Several title compounds exhibited selective inhibitory activities against VEGFR-2 than EGFR kinases, which also displayed selective anti-proliferation potency against the HUVEC and HepG2 than the A549 and MDA-MB-231 cancer cell lines. The newly synthesized compounds were evaluated for anti-angiogenesis capability by chick chorioallantoic membrane (CAM) assay. Among them, compounds 9d showed the most potent anti-angiogenesis ability (79% inhibition at 10 nM/eggs), the efficient cytotoxic activities (in vitro against the HUVEC and HepG2 cell lines with IC₅₀ values of 1.47 and 2.57 μM, respectively), and excellent VEGFR-2 kinase inhibition (IC₅₀ = 0.051 μM). The molecular docking analysis revealed that compound 9d is a Type II inhibitor of VEGFR-2 kinase. These results indicated that the 6-amide-2-arylbenzoxazole and 6-amide-2-aryl benzimidazole derivatives are promising inhibitors of VEGFR-2 kinase for the potential treatment of anti-angiogenesis.

Discovery of 6-Arylurea-2-arylbenzoxazole and 6-Arylurea-2-arylbenzimidazole Derivatives as Angiogenesis Inhibitors: Design, Synthesis and in vitro Biological Evaluation

We embarked on a structural optimization campaign aimed at the discovery of novel anti-angiogenesis agents with previously reported imidazole kinase inhibitors as a lead compound. A library of 29 compounds was synthesized. Several title compounds exhibited selective inhibitory activities against vascular endothelial growth factor receptor 2 (VEGFR-2) over epidermal growth factor receptor (EGFR) kinase; these compounds also displayed selective and potent antiproliferative activity against three cancer cell lines. The newly synthesized compounds were evaluated for anti-angiogenesis activity by chick chorioallantoic membrane (CAM) assay. Among them, 1-(2-(2-chlorophenyl)benzo[d]oxazol-5-yl)-3-(4-(trifluoromethoxy)phenyl)urea (compound 5 n) showed the most potent anti-angiogenesis capacity, efficient cytotoxic activities (in vitro against human umbilical vein endothelial cells (HUVEC), H1975, A549, and HeLa cell lines, with respective IC₅₀ values of 8.46, 1.40, 7.61, and 0.28 μm), and an acceptable level of VEGFR-2 kinase inhibition (IC₅₀ =0.25 μm). Molecular docking analysis revealed 5 n to be a type II inhibitor of VEGFR-2 kinase. In general, these results indicate that these 6-arylurea-2-arylbenzoxazole/benzimidazole derivatives are promising inhibitors of VEGFR-2 kinase for potential development into anti-angiogenesis drugs.

Preparation of Titanocene-Gold Compounds Based on Highly Active Gold(I)-N-Heterocyclic Carbene Anticancer Agents: Preliminary in vitro Studies in Renal and Prostate Cancer Cell Lines

Heterometallic titanocene-based compounds containing gold(I)-phosphane fragments have been extremely successful against renal cancer in vitro and in vivo. The exchange of phosphane by N-heterocyclic carbene ligands to improve or modulate their pharmacological profile afforded bimetallic complexes effective against prostate cancer, but less effective against renal cancer in vitro. Herein we report the synthesis of new bimetallic Ti-Au compounds by the incorporation of two previously reported highly active gold(I)-N-heterocyclic carbene fragments derived from 4,5-diarylimidazoles. The two new compounds [(η5 -C5 H5 )2 TiMe(μ-mba)Au(NHC)] (where NHC=1,3-dibenzyl-4,5-diphenylimidazol-2-ylidene, NHC-Bn 2 a; or 1,3-diethyl-4,5-diphenylimidazol-2-ylidene, NHC-Et 2 b) with the dual linker (-OC(O)-p-C6 H4 -S-) containing both a carboxylate and a thiolate group were evaluated in vitro against renal and prostate cancer cell lines. The compounds were found to be more cytotoxic than previously described Ti-Au compounds containing non-optimized gold(I)-N-heterocyclic fragments. We present studies to evaluate their effects on cell death pathways, migration, inhibition of thioredoxin reductase (TrxR) and vascular endothelial growth factor (VEGF) in the PC3 prostate cancer cell line. The results show that the incorporation of a second metallic fragment such as titanocene into biologically active gold(I) compounds improves their pharmacological profile.

Curcumin Ameliorates Chronic Renal Failure in 5/6 Nephrectomized Rats by Regulation of the mTOR/HIF-1α/VEGF Signaling Pathway

Previous studies implicated the mammalian target of rapamycin (mTOR)/hypoxia-inducible factor-1α (HIF-1α)/vascular endothelial growth factor (VEGF) pathway in renal fibrosis and found that curcumin could suppress the expression of mTOR. Therefore, the aim of the present study was to investigate the therapeutic effects of curcumin against chronic renal failure (CRF) in a rat model induced by 5/6 nephrectomy through inhibition of mTOR/HIF-1α/VEGF signaling. A total of 70 male Sprague-Dawley rats were divided into seven groups: a sham group, a CRF group, and five treatment groups. Except for the sham rats, all rats underwent 5/6 nephrectomy to induce CRF. The 5/6 nephrectomized rats received treatment with curcumin vehicle, everolimus vehicle, curcumin, everolimus, or the combination of curcumin and everolimus. Everolimus, a specific inhibitor of mTOR, was used as a positive control. At the end of treatment, blood biochemical indexes, proteinuria and the kidney index were detected. Moreover, histological change was examined by hematoxylin and eosin staining, and protein expression levels were detected by Western blotting. The blood biochemical indexes, proteinuria, and kidney index were increased in the CRF group as compared to the sham group, which was accompanied by marked activation of the mTOR/HIF-1α/VEGF pathway. However, curcumin, as well as everolimus, restored or ameliorated these changes. These results indicate that activation of the mTOR/HIF-1α/VEGF signaling pathway plays an important role in the occurrence and development of CRF, and that curcumin has renoprotective effects by blocking activation of this pathway.

Pro-Apoptotic and Anti-Angiogenesis Effects of Olive Leaf Extract on Spontaneous Mouse Mammary Tumor Model by Balancing Vascular Endothelial Growth Factor and Endostatin Levels

It has been proven that olive associated products such as olive leaf extract (OLE) causes significant reduction in cancer cells viability and proliferation. Female BALB/c adult mice were divided into four groups. Three days prior to oral treatments, tumors were transplanted. First group were treated with distilled water and other three groups were received, respectively, 75, 150, and 225 mg/kg/day of OLE for three weeks. For assessment of anti-angiogenesis and pro-apoptotic effect of OLE on tumor tissue, tumor volume, cell mitosis and apoptosis, and also vascular endothelial growth factor (VEGF) and endostatin levels were assessed. OLE treatment with 150 and 225 mg/kg/day lead to significant reduction in tumor volume and cell mitosis compared with the control group, while the same doses significantly increase tumor cell apoptosis. OLE treatment with 150 mg/kg/day increase endostatin levels, while the same dose did not significantly decrease VEGF levels. The VEGF level is significantly reduced by the treatment with OLE 225 mg/kg/day for three weeks. Although, further studies are needed to clarify anti-angiogenesis and anti-apoptotic mechanism of OLE, consumption of OLE polyphenols after tumor transplantation reduced spontaneous mouse mammary tumor growth.

Crude microcystins extracted from Microcystis aeruginosa exert anti-obesity effects by downregulating angiogenesis and adipogenesis related signaling molecules in HUVEC and 3 T3-L1 cells

Background

Obesity is a risk factor for many diseases including diabetes, cancer, arthritis, and cardiovascular diseases. Angiogenesis nourishes adipose tissues and contributes to obesity; it can be prevented by suppressing the expression of associated signaling molecules. Natural products have garnered attention owing to their safety and efficacy in treating several diseases, including obesity.

Methods

Crude Microcystins were extracted from the blooming Microcystis aeruginosa under stress conditions, by ultrasonication following by solvent extraction. The microcystin extract was evaluated for its potential of inhibiting angiogenesis and adipogenesis. The antiangiogenic activity of the microcystins extract was investigated using human umbilical vein endothelial cells (HUVECs), and its anti-obesity activity was determined in vitro by quantification of the accumulated lipids in mouse 3 T3-L1 cells via Oil Red O staining method.

Results

The microcystin extract suppressed HUVECs proliferation and tubes formation in Matrigel in a dose-dependent manner. RT-PCR analysis revealed the downregulation of the mRNA expression of angiogenesis-related signaling molecules, such as PI3K, β-catenin, vascular endothelial growth factor receptor-2 (VEGFR-2), vascular endothelial-cadherin, Akt1, and NF-κB. Additionally, it inhibited the differentiation of premature 3 T3 cells and lipid accumulation in a dose-dependent manner. It suppressed adipogenesis and lipogenesis by reducing the expression level of peroxisome proliferator-activated receptor γ, CCAAT/enhancer binding protein α, and sterol regulatory element-binding protein.

Conclusions

Crude microcystin exerts anti-angiogenic and anti-obesity effects due to the inhibitory effects on the genes expression of associated signaling molecules and transcriptional factors.

Adding Nanotechnology to the Metastasis Treatment Arsenal

Metastasis is a major cause of cancer-related mortality, accounting for 90% of cancer deaths. The explosive growth of cancer biology research has revealed new mechanistic network information and pathways that promote metastasis. Consequently, a large number of antitumor agents have been developed and tested for their antimetastatic efficacy. Despite their exciting cytotoxic effects on tumor cells in vitro and antitumor activities in preclinical studies in vivo, only a few have shown potent antimetastatic activities in clinical trials. In this review, we provide a brief overview of current antimetastatic strategies that show clinical efficacy and review nanotechnology-based approaches that are currently being incorporated into these therapies to mitigate challenges associated with treating cancer metastasis.

Synthesis of a novel platinum(II) complex with 6,7-dichloro-5,8-quinolinedione and the study of its antitumor mechanism in testicular seminoma

A new platinum(II) complex, [Pt(ClClQ)(DMSO)Cl] (1), utilizing 6,7-dichloro-5,8-quinolinedione (ClClQ) as a ligand, has been synthesized and fully characterized. Single-crystal X-ray diffraction and other spectroscopic and analytical methods revealed that the coordination geometry of Pt(II) in complex 1 can also be described as a four-coordinated square planar geometry. The aim of the study was to explore the in vitro anticancer properties of complex 1. Our studies showed that complex 1 can regulate the viability of testicular seminoma cells in vitro, including cell proliferation and apoptosis. We further observed negative regulation by complex 1 of the expression levels of the key elements in the phosphoinositide-3 kinase (PI3K)/protein kinase B (Akt)/glycogen synthase kinase-3β (GSK3β) pathway, including phosphorylated phosphoinositide-3 kinase (p-PI3K), phosphorylated protein kinase B(p-Akt) and phosphorylated glycogen synthase kinase-3β (p-GSK3β). Moreover, the negative effect of complex 1 was reversed by LiCl, a GSK3β-specific inhibitor of the PI3K signaling pathway. Meanwhile, the levels of Bcl2 associated death promoter (Bad), cytochrome c, active-caspase-3 and active-caspase-9 increased significantly. In conclusion, we observed that complex 1 can regulate the viability of testicular seminoma cells through the PI3K/Akt/GSK3β signaling pathway and the mitochondria-mediated apoptotic pathway in vitro, and thus, complex 1 may have potential for use as a drug in the treatment of testicular germ cell tumors.

Circular RNAs in Cancer: emerging functions in hallmarks, stemness, resistance and roles as potential biomarkers

Circular RNAs (circRNAs) are a class of RNA molecules with closed loops and high stability. CircRNAs are abundantly expressed in eukaryotic organisms and exhibit both location- and step-specificity. In recent years, circRNAs are attracting considerable research attention attributed to their possible contributions to gene regulation through a variety of actions, including sponging microRNAs, interacting with RNA-binding proteins, regulating transcription and splicing, and protein translation. Growing evidence has revealed that circRNAs play critical roles in the development and progression of diseases, especially in cancers. Without doubt, expanding our understanding of circRNAs will enrich knowledge of cancer and provide new opportunities for cancer therapy. In this review, we provide an overview of the characteristics, functions and functional mechanisms of circRNAs. In particular, we summarize current knowledge regarding the functions of circRNAs in the hallmarks, stemness, resistance of cancer, as well as the possibility of circRNAs as biomarkers in cancer.

Periprostatic fat adipokine expression is correlated with prostate cancer aggressiveness in men undergoing radical prostatectomy for clinically localized disease

OBJECTIVES

To investigate the relationship between periprostatic adipose tissue (PPAT) adipokine expression and prostate cancer (PCa) aggressiveness using both pathological features of radical prostatectomy (RP) and multiparametric magnetic resonance imaging ( MRI) variables.

PATIENTS AND METHODS

Sixty-nine men were recruited to assess immunohistochemical expression of tumour necrosis factor (TNF)α and vascular endothelial growth factor (VEGF) of periprostatic fat of RP specimens. Per cent immunopositivity was quantified on scanned slides using the Aperio Positive Pixel Count algorithm for PPAT TNFα, VEGF and androgen receptors. Periprostatic fat volume (PFV) was segmented on contiguous T₁ -weighted axial MRI slices from the level of the prostate base to apex. PFV was normalized to prostate volume (PV) to account for variations in PV (normalized PFV = PFV/PV). MRI quantitative values (K_ep , K_trans and apparent diffusion coefficient) were measured from the PCa primary lesion using Olea Sphere software. Patients were stratified into three groups according to RP Gleason score (GS): ≤6, 7(3 + 4) and ≥7(4 + 3).

RESULTS

The mean rank of VEGF and TNFα was significantly different between the groups [H(2) = 11.038, P = 0.004] and [H(2) = 13.086, P = 0.001], respectively. Patients with stage pT₃ had higher TNFα (18.2 ± 8.95) positivity than patients with stage pT₂ (13.27 ± 10.66; t [67] = -2.03, P = 0.047). TNFα expression significantly correlated with K_trans (ρ = 0.327, P = 0.023). TNFα (P = 0.043), and VEGF (P = 0.02) correlated with high grade PCa (GS ≥ 7) in RP specimens and also correlated significantly with upgrading of GS from biopsy to RP histology.

CONCLUSIONS

The expression levels of TNFα and VEGF on immunostaining significantly correlated with aggressivity of PCa. As biomarkers, these indicate the risk of having high grade PCa in men undergoing RP.

A literature analysis on anti-vascular endothelial growth factor therapy (anti-VEGF) using a bibliometric approach

We performed the current study to assess the citation performance of research works on anti-vascular endothelial growth factor (anti-VEGF) therapy. We searched Web of Science (WoS) to identify relevant publications and analyze them with reference to their publication year, journal title, citation count, WoS category, and article type. The bibliometric software (VOSviewer) was used for citation analyses of countries and journals and to generate a term map that visualizes the recurring terms appearing in the titles and abstracts of published articles. The literature search resulted in 7364 articles, with a mean citation count of 26.2. Over half of them (50.2%) were published during the past 5 years. Original articles constituted the majority (67.8%). The publications were mainly classified into WoS categories of ophthalmology (43.2%) and oncology (20.6%). The most prolific ophthalmology and cancer journals were Investigative Ophthalmology & Visual Science (7.3%) and Cancer Research (1.4%), respectively. The correlation between journal impact factor and citation count was weak to moderate (for journals with impact factor up to 5 and 10, respectively), and open-access articles had significantly more citations than non-open-access articles (p < 0.001). The frequently targeted tumors by anti-VEGF therapy included metastatic colorectal cancer (196; 49.2 citations per article (CPA)), breast cancers (167; 37.2 CPA), and renal cell carcinoma (122; 38.2 CPA). The frequently targeted eye pathologies were age-related macular degeneration (828; 18.2 CPA), diabetic macular edema (466; 10.8 CPA), and diabetic retinopathy (358; 31.9 CPA). These results indicate that anti-VEGF therapy has a wide range of applications and its publications are highly cited.

Aurora kinase inhibitor VX‑680 suppresses the proliferation and migration of HUVECs and angiogenesis

Angiogenesis serves a key role in tumor growth and metastasis. VX‑680, a potent inhibitor targeting the Aurora kinase family, is widely used in the inhibition of tumor progression. However, the effect of VX‑680 on angiogenesis remains unknown. The present study identified that VX‑680 inhibited human umbilical vein endothelial cell (HUVEC) proliferation and promoted HUVEC apoptosis by inducing the cleavage of PARP and caspase‑3. VX‑680 also markedly decreased the migration and tube formation of HUVECs in a dose‑dependent manner. In addition, VX‑680 significantly suppressed the formation of blood vessels in a dose‑dependent manner confirmed by a chicken embryo chorioallantoic membrane assay in vivo. Furthermore, VX‑680 inhibited the expression levels of vascular endothelial growth factor and phosphorylated RAC‑α serine/threonine‑protein kinase in HUVECs. These results suggested that VX‑680 suppressed angiogenesis and may be a potential novel anti‑angiogenic agent.

3D-ASL perfusion correlates with VEGF expression and overall survival in glioma patients: Comparison of quantitative perfusion and pathology on accurate spatial location-matched basis

BACKGROUND

There is a need for an imaging-based tool for measuring vascular endothelial growth factor (VEGF) expression and overall survival (OS) in patients with glioma.

PURPOSE

To assess the correlation between cerebral blood flow (CBF), measured by 3D pseudo-continuous arterial spin-labeling (3D-ASL), and VEGF expression in gliomas on the basis of coregistered localized biopsy, and investigate whether CBF correlated with survival month (SM) in glioma patients.

STUDY TYPE

Prospective cohort.

SUBJECTS

Thirty-seven patients with gliomas from whom 63 biopsy specimens were obtained.

SEQUENCE

3D-ASL acquired with a 3.0T MR unit.

ASSESSMENT

Biopsy specimens were grouped as high-grade (HGG) or low-grade glioma (LGG). CBF measurements were spatially matched with VEGF expression by coregistered localized biopsies, and the CBF value was correlated with quantitative VEGF expression for each specimen. Patients' survival information was derived and connected with CBF.

STATISTICAL TESTS

Patients' OS was analyzed by Kaplan-Meier and Cox-regression methods. VEGF expression and CBF were compared in both LGG and HGG. The Spearman rank correlation was calculated for CBF and VEGF expression, SM. Significance level, P < 0.05.

RESULTS

CBF-derived 3D-ASL positively correlated significantly with VEGF expression in both LGG (31 specimens) and HGG (32 specimens), r = 0.604 (P < 0.001) and r = 0.665 (P < 0.001), respectively. LGG and HGG together gave a correlation coefficient r = 0.728 (P < 0.001). Median survival for LGG and HGG patients was 34.19 and 17.17 months, respectively (P = 0.037); CBF value negatively correlated significantly with SM with r = -0.714 (P < 0.001) regardless of glioma grade. CBF was an independent risk factor for OS with HR = 1.027 (P = 0.044), 1.028 (P = 0.010) for univariate/multivariate regression analysis.

DATA CONCLUSION

CBF determined by 3D-ASL correlates with VEGF expression in glioma and is an independent risk factor for OS in these patients.

LEVEL OF EVIDENCE

1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;50:209-220.

Type IIA - Type IIB protein tyrosine kinase inhibitors hybridization as an efficient approach for potent multikinase inhibitor development: Design, synthesis, anti-proliferative activity, multikinase inhibitory activity and molecular modeling of novel indolinone-based ureides and amides

Pursuing on our efforts regarding development of novel multikinase inhibitors, herein we report the design and synthesis of novel 2-indolinone-based ureides 6a-u and amides 10a-j. In this work we adopt a hybridization strategy between type IIA PTK inhibitor (sorafenib) and type IIB PTK inhibitors (sunitinib and nintedanib). This was implemented via linking the indolinone core, in both sunitinib and nintedanib, which is well-fitted in the hinge region in the kinase domain front cleft and the biaryl urea extension, in sorafenib, which is accommodated in the gate area and the hydrophobic back pocket. Molecular docking of the designed hybrid compounds in VEGFR-2 and FGFR-1 active sites revealed, as planned, their ability to establish the binding interactions achieved by both original type IIA and type IIB inhibitors. The designed compounds were evaluated for their multikinase inhibitory activity towards VEGFR-2, PDGFR-b and FGFR-1 and anti-proliferative activity towards HepG2, MCF-7, A549 and A498 cancer cell lines. The ureido analogue 6u emerged as the most potent multikinase inhibitor in the ureido series with VEGFR-2, FGFR-1 and PDGFR-b IC₅₀ of 0.18, 0.23 and 0.10 μM, respectively. Whereas, the amido congener 10j emerged as the most potent multikinase inhibitor in the amide series with VEGFR-2, FGFR-1 and PDGFR-b IC₅₀ of 0.28, 0.46 and 0.09 μM, respectively. While, indolinone 6u was the most potent derivative towards HepG2 cells (IC₅₀ = 2.67 ± 0.14 μM), 6r stood out as the most potent indolinone against A498 cells (IC₅₀ = 0.78 ± 0.02 μM). Additionally, the target indolinones displayed non-significant cytotoxic impact towards human normal melanocyte (HFB4). ADME prediction study of the designed compounds showed that they are not only with promising multikinase inhibitory activity but also with favorable pharmacokinetic and drug-likeness properties. Compounds 6r and 10j are revealed to be the best compounds in terms of multikinase activity and pharmacokinetics.

Presence of trophoblast in the uterine lumen affects VEGF-C expression in porcine endometrium

Early pregnancy is associated with morphological and functional changes within the uterus, accompanied by angiogenesis, increased vascular permeability and activation of immune tolerance. Intensive angiogenesis leads to accelerated vascular leakage and accumulation of interstitial fluid in endometrium. To protect the trophoblast from the harmful effect of extracellular fluid, process known as lymphangiogenesis is crucial. These studies are focused on VEGF-C, factor responsible of lymphatic vessels creating, and its receptors: Flk1 (VEGFR2) and Flt4 (VEGFR3) during the time of implantation as well as the effect of trophoblast signals (IFNG and E2) on VEGF-C production. Endometrial samples were collected from mature gilts from days 8, 10, 12, 14 of estrous cycle and pregnancy. Real-Time PCR analysis revealed increased mRNA expression of VEGF-C on days 10, 12, 14 of pregnancy compared to corresponding days of estrous cycle. The highest VEGF-C mRNA expression was observed on 14 day of pregnancy (p < 0.05). Increased mRNA expression of Flk1 and Flt4 was noticed on day 14 of pregnancy in comparison to day 10. Enhanced Flk1 mRNA expression during 14 day of pregnancy was observed compared to corresponding day of estrous cycle (p < 0.05). No significant difference on the protein level was revealed. VEGF-C and its receptors were localized mainly in luminal and glandular epithelial cells, but their presence were confirmed also in endothelial cells of blood and lymphatic vessels and 14 d trophoblasts. In vitro studies revealed positive effect of IFNG on VEGF-C mRNA expression in stromal cells and protein content in medium after stromal cells culture (p < 0.05). Our studies demonstrated the presence of VEGF-C system in porcine endometrium and indicated its possible important role during the time of implantation.

Bimetallic titanocene-gold phosphane complexes inhibit invasion, metastasis, and angiogenesis-associated signaling molecules in renal cancer

Following promising recent in vitro and in vivo studies of the anticancer efficacies of heterometallic titanocene-gold chemotherapeutic candidates against renal cancer, we report here on the synthesis, characterization, stability studies and biological evaluation of a new titanocene complex containing a gold-triethylphosphane fragment [(η-C₅H₅)₂TiMe(μ-mba)Au(PEt₃)] (4) Titanofin. The compound is more stable in physiological fluid than those previously reported, and it is highly cytotoxic against a line of human clear cell renal carcinoma. We describe here preliminary mechanistic data for this compound and previously reported [(η-C₅H₅)₂TiMe(μ-mba)Au(PPh₃)] (2) Titanocref which displayed remarkable activity in an in vivo mouse model. Mechanistic studies were carried out in the human clear cell renal carcinoma Caki-1 line for the bimetallic compounds [(η-C₅H₅)₂TiMe(μ-mba)Au(PR₃)] (PR₃ = PPh₃2 Titanocref and PEt₃4 Titanofin), the two monometallic gold derivatives [Au(Hmba)(PR₃)] (PR₃ = PPh₃1 cref; PEt₃3 fin), titanocene dichloride and Auranofin as controls. These studies indicate that bimetallic compounds Titanocref (2) and Titanofin (4) are more cytotoxic than gold monometallic derivatives (1 and 3) and significantly more cytotoxic than titanocene dichloride while being quite selective. Titanocref (2) and Titanofin (4) inhibit migration, invasion, and angiogenic assembly along with molecular markers associated with these processes such as prometastatic IL(s), MMP(s), TNF-α, and proangiogenic VEGF, FGF-basic. The bimetallic compounds also strongly inhibit the mitochondrial protein TrxR often overexpressed in cancer cells evading apoptosis and also inhibit FOXC2, PECAM-1, and HIF-1α whose overexpression is linked to resistance to genotoxic chemotherapy. In summary, bimetallic titanocene-gold phosphane complexes (Titanocref 2 and Titanofin 4) are very promising candidates for further preclinical evaluations for the treatment of renal cancer.

Physcomitrella patens, a versatile synthetic biology chassis

During three decades the moss Physcomitrella patens has been developed to a superb green cell factory with the first commercial products on the market. In the past three decades the moss P. patens has been developed from an obscure bryophyte to a model organism in basic biology, biotechnology, and synthetic biology. Some of the key features of this system include a wide range of Omics technologies, precise genome-engineering via homologous recombination with yeast-like efficiency, a certified good-manufacturing-practice production in bioreactors, successful upscaling to 500 L wave reactors, excellent homogeneity of protein products, superb product stability from batch-to-batch, and a reliable procedure for cryopreservation of cell lines in a master cell bank. About a dozen human proteins are being produced in P. patens as potential biopharmaceuticals, some of them are not only similar to their animal-produced counterparts, but are real biobetters with superior performance. A moss-made pharmaceutical successfully passed phase 1 clinical trials, a fragrant moss, and a cosmetic moss-product is already on the market, highlighting the economic potential of this synthetic biology chassis. Here, we focus on the features of mosses as versatile cell factories for synthetic biology and their impact on metabolic engineering.

Oestrogen Inhibits VEGF Expression And Angiogenesis In Triple-Negative Breast Cancer By Activating GPER-1

Triple-negative breast cancer (TNBC) is the most malignant type of breast cancer with ample vascularisation and high vascular endothelial growth factor (VEGF) expression. The sex steroid hormone oestrogen is involved in several cellular activities associated with TNBC regulation. However, the role of oestrogen in VEGF expression and angiogenesis in TNBC remains unclear. In this study, we found that treatment with 17β-oestradiol (E2) inhibited VEGF mRNA and protein expression in the TNBC cell lines MDA-MB-468 and MDA-MB-436. To further elaborate on the phenomenon of E2-regulated angiogenesis, we showed that conditioned medium from the TNBC cell line MDA-MB-468 treated with E2 inhibits the tube formation ability of human umbilical vein endothelial cells (HUVECs). Additionally, the G-protein-coupled oestrogen receptor-1 (GPER-1)-specific agonist G-1 has a function similar to that of E2. While G-15, the selective antagonist of GPER-1, notably reversed the inhibitory effects of E2 and G-1 on VEGF expression and tube formation, suggesting that GPER-1 is involved in the E2-induced angiogenesis suppression in TNBC cells. Moreover, E2 inhibited in vivo tumour growth and angiogenesis and reduced the expression levels of VEGF, NF-κB/p65, STAT3, and the endothelial marker CD34 in MDA-MB-468 xenograft tumours. Our findings provide important evidence that E2 can inhibit VEGF expression and angiogenesis in TNBC by activating GPER-1, offering additional insight into tumour angiogenesis and targets for drug intervention in TNBC.

VEGF165b, a splice variant of VEGF-A, promotes lung tumor progression and escape from anti-angiogenic therapies through a β1 integrin/VEGFR autocrine loop

Vascular endothelial growth factor-A (VEGF-A) is highly subjected to alternative pre-mRNA splicing that generates several splice variants. The VEGF_xxx and VEGF_xxxb families encode splice variants of VEGF-A that differ only at the level of six amino acids in their C-terminal part. The expression level of VEGF_xxx splice variants and their function as pro-angiogenic factors during tumor neo-angiogenesis have been well-described. The role of VEGF_xxxb isoforms is less well known, but they have been shown to inhibit VEGF_xxx-mediated angiogenesis, while being partial or weak activators of VEGFR receptors in endothelial cells. On the opposite, their role on tumor cells expressing VEGFRs at their surface remains largely unknown. In this study, we find elevated levels of VEGF₁₆₅b, the main VEGF_xxxb isoform, in 36% of non-small cell lung carcinoma (NSCLC), mainly lung adenocarcinoma (46%), and show that a high VEGF₁₆₅b/VEGF₁₆₅ ratio correlates with the presence of lymph node metastases. At the molecular level, we demonstrate that VEGF₁₆₅b stimulates proliferation and invasiveness of two lung tumor cell lines through a VEGFR/β1 integrin loop. We further provide evidence that the isoform-specific knockdown of VEGF₁₆₅b reduces tumor growth, demonstrating a tumor-promoting autocrine role for VEGF₁₆₅b in lung cancer cells. Importantly, we show that bevacizumab, an anti-angiogenic compound used for the treatment of lung adenocarcinoma patients, increases the expression of VEGF₁₆₅b and activates the invasive VEGFR/β1 integrin loop. Overall, these data highlight an unexpected role of the VEGF₁₆₅b splice variant in the progression of lung tumors and their response to anti-angiogenic therapies.

Therapeutic implication of vascular endothelial growth factor receptor-1 (VEGFR-1) targeting in cancer cells and tumor microenvironment by competitive and non-competitive inhibitors

The vascular endothelial growth factor receptor-1 (VEGFR-1) is a tyrosine kinase receptor for VEGF-A, VEGF-B, and placental growth factor (PlGF) ligands that is expressed in endothelial, myelomonocytic and tumor cells. VEGF-B and PlGF exclusively bind to VEGFR-1, whereas VEGF-A also binds to VEGFR-2. At variance with VEGFR-2, VEGFR-1 does not play a relevant role in physiological angiogenesis in the adult, while it is important in tumor-associated angiogenesis. VEGFR-1 and PlGF are expressed in a variety of tumors, promote invasiveness and contribute to resistance to anti-VEGF-A therapy. The currently approved antiangiogenic therapies for the treatment of a variety of solid tumors hamper VEGF-A signaling mediated by both VEGFR-2 and VEGFR-1 [i.e., the monoclonal antibody (mAb) anti-VEGF-A bevacizumab, the chimeric molecule aflibercept and several small molecule tyrosine kinase inhibitors] or exclusively by VEGFR-2 (i.e., the mAb anti-VEGFR-2 ramucirumab). However, molecules that interfere with VEGF-A/VEGFR-2 signaling determine severe adverse effects due to inhibition of physiological angiogenesis and their efficacy is hampered by tumor infiltration of protumoral myeloid cells. Blockade of VEGFR-1 may exert anti-tumor activity by multiple mechanisms: a) inhibition of tumor-associated angiogenesis; b) reduction of myeloid progenitor mobilization and tumor infiltration by VEGFR-1 expressing M2 macrophages, which contribute to tumor progression and spreading; c) inhibition of invasiveness, vasculogenic mimicry and survival of VEGFR-1 positive tumor cells. As a consequence of these properties, molecules targeting VEGFR-1 are expected to produce less adverse effects and to counteract resistance towards anti-VEGF-A therapies. More interestingly, selective VEGFR-1 inhibition might enhance the efficacy of immunotherapy with immune checkpoint inhibitors. In this review, we will examine the experimental evidence available so far that supports targeting VEGFR-1 signal transduction pathway for cancer treatment by competitive inhibitors that prevent growth factor interaction with the receptor and non-competitive inhibitors that hamper receptor activation without affecting ligand binding.

Structure and function of vascular endothelial growth factor and its receptor system

Vascular endothelial growth factor and its receptor (VEGF-VEGFR) system play a critical role in the regulation of angiogenesis and lymphangiogenesis in vertebrates. Each of the VEGF has specific receptors, which it activates by binding to the extracellular domain of the receptors, and, thus, regulates the angiogenic balance in the early embryonic and adult stages. However, de-regulation of the VEGF-VEGFR implicates directly in various diseases, particularly cancer. Moreover, tumor growth needs a dedicated blood supply to provide oxygen and other essential nutrients. Tumor metastasis requires blood vessels to carry tumors to distant sites, where they can implant and begin the growth of secondary tumors. Thus, investigation of signaling systems related to the human disease, such as VEGF-VEGFR, will facilitate the development of treatments for such illnesses. [BMB Reports 2018; 51(2): 73-78].

FOXP3 inhibits angiogenesis by downregulating VEGF in breast cancer

Forkhead box P3 (FOXP3), an X-linked tumor suppressor gene, plays an important role in breast cancer. However, the biological functions of FOXP3 in breast cancer angiogenesis remain unclear. Here we found that the clinical expression of nuclear FOXP3 was inversely correlated with breast cancer angiogenesis. Moreover, the animal study demonstrated that FOXP3 significantly reduced the microvascular density of MDA-MB-231 tumors transplanted in mice. The cytological experiments showed that the supernatant from FOXP3-overexpressing cells exhibited a diminished ability to stimulate tube formation and sprouting in HUVECs in vitro. In addition, expression of vascular endothelial growth factor (VEGF) was downregulated by FOXP3 in breast cancer cell lines. Luciferase reporter assays and chromatin immunoprecipitation assays demonstrated that FOXP3 can directly interact with the VEGF promoter via specific forkhead-binding motifs to suppress its transcription. Importantly, the inhibitory effects of FOXP3 in the supernatant on tube formation and sprouting in HUVECs could be reversed by adding VEGF in vitro. Nuclear FOXP3 expression was inversely correlated with VEGF expression in clinical breast cancer tissues, and FOXP3 downregulation and VEGF upregulation were both correlated with reduced survival in breast cancer data sets in the Kaplan–Meier plotter. Taken together, our data demonstrate that FOXP3 suppresses breast cancer angiogenesis by downregulating VEGF expression.

Tivozanib for the treatment of renal cell carcinoma

INTRODUCTION

Renal cell carcinoma (RCC) represents a heterogeneous group of cancers with distinct histological features, molecular alterations, prognosis, and response to therapy. Target agents directed against vascular endothelial growth factor and its receptor and mammalian target of rapamycin (mTOR) inhibitors have completely changed the landscape of RCC. However, the rate of complete response is still low, thus supporting the research of novel therapeutic agents. Area covered: The authors describe the chemical features of tivozanib, its pharmacodynamic and pharmacokinetic properties, and the results obtained in human phase I-III clinical trials. Tivozanib received its first global approval in EU, Iceland, and Norway on 28 August 2017 for the first-line treatment of adult patients with advanced RCC and for adult patients who are VEGFR and mTOR inhibitor-naive following disease progression after one prior treatment with cytokines. Expert opinion: The US Food and Drug Administration did not approve tivozanib due to the lack of a significant advantage in terms of survival compared to sorafenib. To date, the role of tivozanib in the pharmaceutical landscape of mRCC appears to be very limited. However, ongoing trials on the association between tivozanib and immunotherapy may represent a promising strategy to be assessed in future clinical trials.

VEGFA and VEGFR2 RNAscope determination in gastric cancer

Gastric cancer is the fifth most common cancer and third leading cause of cancer-related death worldwide. Several studies on angiogenic blocking agents in gastric cancer revealing promising results by the use of monoclonal antibodies against VEGFA or its receptor VEGFR2 or against VEGFA activating pathway. The validation of biomarkers useful to better organize the clinical trials involving anti-angiogenic therapies is crucial. Molecular markers such as RNA are increasingly used for cancer diagnosis, prognosis, and therapy guidance as in the case of the targeted therapies concerning the inhibition of angiogenesis. The aim of this study is to set the conditions for evaluating the expression of VEGFA and VEGFR2 in gastric cancer specimens and in healthy gastric mucosa by the use of RNAscope, a novel RNA in situ hybridization (ISH) method that allows the visualization of a specific gene expression in individual cells. We found the increased expression of VEGFA in the tubular glands and VEGFR2 in the endothelium of gastric cancer samples mainly in the T2, T3 and T4 stages of tumor progression as compared to the healthy controls. These results obtained by the application of this highly sensitive method for oligonucleotide detection the role of angiogenesis in gastric cancer progression already highlighted by conventional immunohistochemical methods, and offer significant promise as a new platform for developing and implementing RNA-based molecular diagnostics also in the conditions in which immunohistochemistry is not applicable.

MDA-MB-231 and 8701BC breast cancer lines promote the migration and invasiveness of ECV304 cells on 2D and 3D type-I collagen matrix

Tumor angiogenesis is a multiphasic process, having the extracellular matrix remodeling as critical step. Different classes of proteolytic enzymes in matrix digestion/remodeling are involved. The role of lytic enzymes and their activation mode have not been completely elucidated. Herein, the crosstalk between endothelia and tumor cells, by realization of bi- and three-dimensional endothelial and breast cancer cells co-cultures, were studied in vitro. Particularly, the effects of two tumor conditioned media (TCM) were assessed about endothelial proliferation, migration, and invasiveness. An increase in expression of pro-MMP9 was detected when endothelial cells were cultured in the presence of both TCM; such as an up-regulation of MMP1 and MMP14 and a down-regulation of MMP7. Moreover the increased MMP2 gene expression from one of them and the stimulation MMP3 synthesis from the other one were observed; an increases of β3-integrin, VEGFA, and DPP4 molecules were detected when endothelia cells are cultured with both TCM. The selection/characterization of elements present in conditioned media from breast cancer cells differently affect endothelial cells, make them potential effectors useful in breast cancer treatment.

The promising future of microalgae: current status, challenges, and optimization of a sustainable and renewable industry for biofuels, feed, and other products

Microalgae have recently attracted considerable interest worldwide, due to their extensive application potential in the renewable energy, biopharmaceutical, and nutraceutical industries. Microalgae are renewable, sustainable, and economical sources of biofuels, bioactive medicinal products, and food ingredients. Several microalgae species have been investigated for their potential as value-added products with remarkable pharmacological and biological qualities. As biofuels, they are a perfect substitute to liquid fossil fuels with respect to cost, renewability, and environmental concerns. Microalgae have a significant ability to convert atmospheric CO2 to useful products such as carbohydrates, lipids, and other bioactive metabolites. Although microalgae are feasible sources for bioenergy and biopharmaceuticals in general, some limitations and challenges remain, which must be overcome to upgrade the technology from pilot-phase to industrial level. The most challenging and crucial issues are enhancing microalgae growth rate and product synthesis, dewatering algae culture for biomass production, pretreating biomass, and optimizing the fermentation process in case of algal bioethanol production. The present review describes the advantages of microalgae for the production of biofuels and various bioactive compounds and discusses culturing parameters.

New insights into the regulatory role of microRNA in tumor angiogenesis and clinical implications

Angiogenesis is essential for tumor growth and metastasis. Understanding the regulation of tumor angiogenesis has become increasingly important. MicroRNAs (miRNAs) are small noncoding RNAs that function in diverse biological processes via post-transcriptional regulation. Extensive studies have revealed two important regulatory roles of miRNAs in tumor angiogenesis: miRNAs in tumor cells affect the activity of endothelial cells via non-cell-autonomous mechanisms, and miRNAs in endothelial cells regulate the cell-autonomous behavior. Recent advances have further highlighted the role of tumor-derived extracellular vesicles in the regulation of tumor angiogenesis via transferring miRNAs to endothelial cells. In this review, we summarize the regulatory role of miRNA in tumor angiogenesis, with a highlight on clinical implications of miRNAs as biomarkers for anti-angiogenic therapy response, and as therapeutic interventions against tumor angiogenesis in vivo.

Antitumor effects of Tubeimoside-1 in NCI-H1299 cells are mediated by microRNA-126-5p-induced inactivation of VEGF-A/VEGFR-2/ERK signaling pathway

Tubeimoside-1 (TBMS1), a triterpenoid saponin isolated from the tuber of Bolbostemma paniculatum (Maxim) Franquet, serves an universal suppressive role in multiple cancer types, including lung cancer. However, the mechanism involved in non-small cell lung cancer (NSCLC) cells by which TBMS1 elicits its antitumor effects is not yet completely understood. The present study indicated that 10 µmol/l TBMS1 significantly enhanced apoptosis and notably blocked the migration and invasion of NCI-H1299 cells. These effects were reversed following transfection with miR-126-5p inhibitor into TBMS1-treated NCI-H1299 cells. Vascular endothelial growth factor-A (VEGF-A) is a target gene for miR-126-5p. Notably, results suggested that the downregulated VEGF-A and VEGFR-2 in TBMS1-treated NCI-H1299 cells were upregulated after inhibiting miR-126-5p, and overexpression of VEGF-A or VEGFR-2 could significantly reduce apoptosis and promote the migration and invasion of TBMS1-treated NCI-H1299 cells. Furthermore, TBMS1 combined with TBHQ (an ERK activator) dramatically suppressed TBMS1-induced apoptosis and stimulated TBMS1-reduced migration and invasion in NCI-H1299 cells, suggesting that TBMS1 inhibits the ERK signaling pathway and represses the growth and metastasis of NCI-H1299 cells. Further study demonstrated that either inhibiting miR-126-5p or overexpressing VEGF-A and VEGFR-2 in TBMS1-treated NCI-H1299 cells elevated the mRNA expression levels and phosphorylation levels of MEK1, as well as ERK. To conclude, TBMS1 increases miR-126-5p expression, whereas overexpressing miR-126-5p inactivates VEGF-A/VEGFR-2/ERK signaling pathway, which ultimately actuates the pro-apoptotic and anti-metastatic effects in NCI-H1299 cells. Therefore, the present findings provide a theoretical foundation for TBMS1 as a potential candidate in NSCLC treatment.

G Protein-Coupled Receptors at the Crossroad between Physiologic and Pathologic Angiogenesis: Old Paradigms and Emerging Concepts

G protein-coupled receptors (GPCRs) have been implicated in transmitting signals across the extra- and intra-cellular compartments, thus allowing environmental stimuli to elicit critical biological responses. As GPCRs can be activated by an extensive range of factors including hormones, neurotransmitters, phospholipids and other stimuli, their involvement in a plethora of physiological functions is not surprising. Aberrant GPCR signaling has been regarded as a major contributor to diverse pathologic conditions, such as inflammatory, cardiovascular and neoplastic diseases. In this regard, solid tumors have been demonstrated to activate an angiogenic program that relies on GPCR action to support cancer growth and metastatic dissemination. Therefore, the manipulation of aberrant GPCR signaling could represent a promising target in anticancer therapy. Here, we highlight the GPCR-mediated angiogenic function focusing on the molecular mechanisms and transduction effectors driving the patho-physiological vasculogenesis. Specifically, we describe evidence for the role of heptahelic receptors and associated G proteins in promoting angiogenic responses in pathologic conditions, especially tumor angiogenesis and progression. Likewise, we discuss opportunities to manipulate aberrant GPCR-mediated angiogenic signaling for therapeutic benefit using innovative GPCR-targeted and patient-tailored pharmacological strategies.

Expression, purification and functionality of bioactive recombinant human vascular endothelial growth factor VEGF165 in E. coli

Vascular endothelial growth factor (VEGF) is associated with tumour growth and metastasis. Because VEGF is the major player in both angiogenesis and vascular permeability and the most explored factor in angio-inhibitory therapies, many expression procedures have been developed to produce functional VEGF₁₆₅ in convenient yield. In this study, recombinant human VEGF₁₆₅ was cloned and expressed in Escherichia coli (BL21)-DE3 cells and large scale production was performed by fermentation. A high yield of active soluble protein was obtained after protein extraction employing both lysozyme and sonication treatment. Inclusion bodies were also isolated from the cell lysate and subjected to a simple protocol of solubilisation and refolding. Single-step purification was performed using nickel affinity chromatography and the purified proteins were able to recognize monoclonal Anti-poly-His antibody. The biological activity of the VEGF₁₆₅ was successfully tested using the Chicken chorioallantoic membrane assay, wound-healing migration and proliferation assay on human umbilical vein endothelial cells (HUVEC).

Bisphenol A induces proliferative effects on both breast cancer cells and vascular endothelial cells through a shared GPER-dependent pathway in hypoxia

Based on the breast cancer cells and the vascular endothelial cells are both estrogen-sensitive, we proposed a close reciprocity existed between them in the tumor microenvironment, via shared molecular mechanism affected by environmental endocrine disruptors (EDCs). In this study, bisphenol A (BPA), via triggering G-protein estrogen receptor (GPER), stimulated cell proliferation and migration of bovine vascular endothelial cells (BVECs) and breast cancer cells (SkBr-3 and MDA-MB-231) and enhanced tumor growth in vivo. Moreover, the expression of both hypoxia inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) were up-regulated in a GPER-dependent manner by BPA treatment under hypoxic condition, and the activated GPER induced the HIF-1α expression by competitively binding to caveolin-1 (Cav-1) and facilitating the release of heat shock protein 90 (HSP90). These findings show that in a hypoxic microenvironment, BPA promotes HIF-1α and VEGF expressions through a shared GPER/Cav-1/HSP90 signaling cascade. Our observations provide a probable hypothesis that the effects of BPA on tumor development are copromoting relevant biological responses in both vascular endothelial and breast cancer cells.

Molecular regulation and role of angiogenesis in reproduction

Angiogenesis is an essential process for proper functioning of the female reproductive system and for successful pregnancy realization. The multitude of factors required for physiological angiogenesis and the complexity of regulation of their temporal-spatial activities contribute to aberrations in human fertilization and pregnancy outcomes. In this study, we reviewed the current knowledge of the temporal expression patterns, functions, and regulatory mechanisms of angiogenic factors during foliculogenesis, early implantation/placentation and embryo development, as well as recurrent spontaneous abortions. Angiogenic factors including vascular endothelial growth factors and angiopoietins have documented roles in the development of primordial follicles into mature antral follicles. They also participate in decidualization, which is accompanied by the creation of an extensive network of vessels in the stromal bed that support the growth of the embryo and the placenta, and maintain early pregnancy. During placentation angiogenic and angiomodulatory cytokines, T and B lymphocytes and macrophages affect angiogenesis in a context-dependent manner. Defects in angiogenesis at the maternal-fetal interface contribute to miscarriage in humans. The establishment of more polymorphisms in the genes involved in angiogenesis/vasculogenesis, and their pathological phenotype and expression could give opportunities for prediction, creating a therapeutic strategy, and treatment of diseases related to female reproductive health and problematic conception.

BRCA mutations in the manifestation and treatment of ovarian cancer

BRCA genes are important for the integrity and stability of genetic material and play key roles in repairing DNA breaks via high fidelity homologous recombination. BRCA mutations are known to predispose carriers to gynecological malignancies, accounting for a majority of hereditary OC cases. Known to be lethal, OC is difficult to detect and control. Testing for BRCA mutations is a key step in the risk assessment, prognosis, treatment and prevention of OC and current clinical guidelines recommend BRCA mutation testing for all OCs of epithelial origin. Studies have established that ovarian tumors harboring BRCA mutations have distinct molecular and histo-pathological features that can be exploited for effective, targeted treatment. Deficiencies in DNA repair pathways that arise as a result of BRCA mutations make them hypersensitive to DNA-damaging treatments such as platinum chemotherapy and PARP inhibitors. Different combinations of treatment regimens which have the potential to greatly improve prognosis and disease outcomes are currently being evaluated. However, the issue of developing resistance to these treatments remains unresolved. This review emphasizes unique features of BRCA mutated OC and outlines the lay of the land in terms of diagnosis and treatment, while aiming to unravel the challenges that are part of its management.

The mechanisms of IL-17A on promoting tumor metastasis

In recent decades, extensive studies have indicated that IL-17A plays an important role in tumor progression and metastasis, but the underlying mechanisms are not immediately clear. In this review, we examined the literature from the recent years concerning the study of IL-17A in four kinds of tumor transfer paths, including hematogenous metastasis, lymphatic metastasis, local invasion and transcoelomic metastasis, to summarize the roles and underlying mechanisms of IL-17A on tumor metastasis.

Downregulation of microRNA-195 promotes angiogenesis induced by cerebral infarction via targeting VEGFA

Angiogenesis, the formation of new blood vessels from preexisting endothelium, is a process that involves a series of interassociated and mutually interactive pathophysiological processes. It is accepted that microRNAs (miRNAs) regulate endothelial cell behavior, including their involvement in angiogenesis. However, it remains unclear whether miRNAs are involved in the regulation of angiogenesis following cerebral ischemia. Therefore, the present study aimed to investigate the role of miRNAs in angiogenesis and the underlying mechanism following cerebral ischemia. Expression profiles of miRNAs in rat brain samples following middle cerebral artery occlusion (MCAO) were investigated using a miRNA microarray. The expression of candidate miRNA, miR‑195 was further validated using reverse transcription‑quantitative polymerase chain reaction. Then, the effects of miR‑195 on cell migration and tube formation of human umbilical vein vascular endothelial cells (HUVECs) were investigated following miR‑195 silencing, and overexpression. The specific target genes of miR‑195 were predicted using microRNA prediction bioinformatics software (http://www.microrna.org/microrna/home.do), and then confirmed using a dual‑luciferase reporter assay and rescue experiment. It was demonstrated that miR‑195 was significantly downregulated in the brains of rats following MCAO and in hypoxia‑induced HUVECs. Furthermore, it was revealed that miR‑195 overexpression inhibited the invasion ability and tube formation of HUVECs in vitro, while miR‑195 silencing enhanced these functions. In addition, vascular endothelial growth factor A (VEGFA) was identified as a direct target of miR‑195 and was negatively correlated with miR‑195 expression. In addition, the rescue experiment revealed that overexpression of VEGFA reversed the inhibitory effects of miR‑195 overexpression on the invasion ability and tube formation of HUVECs. The present study has provided a novel insight into the promoting roles of miR‑195 downregulation on angiogenesis following cerebral infarction and suggests that the miR‑195/VEGFA signaling pathway is a putative therapeutic target in cerebral ischemia.

Elevated TATA-binding protein expression drives vascular endothelial growth factor expression in colon cancer

The TATA-binding protein (TBP) plays a central role in eukaryotic gene transcription. Given its key function in transcription initiation, TBP was initially thought to be an invariant protein. However, studies showed that TBP expression is upregulated by oncogenic signaling pathways. Furthermore, depending on the cell type, small increases in cellular TBP amounts can induce changes in cellular growth properties towards a transformed phenotype. Here we sought to identify the specific TBP-regulated gene targets that drive its ability to induce tumorigenesis. Using microarray analysis, our results reveal that increases in cellular TBP concentrations produce selective alterations in gene expression that include an enrichment for genes involved in angiogenesis. Accordingly, we find that TBP levels modulate VEGFA expression, the master regulator of angiogenesis. Increases in cellular TBP amounts induce VEGFA expression and secretion to enhance cell migration and tumor vascularization. TBP mediates changes in VEGFA transcription requiring its recruitment at a hypoxia-insensitive proximal TSS, revealing a mechanism for VEGF regulation under non-stress conditions. The results are clinically relevant as TBP expression is significantly increased in both colon adenocarcinomas as well as adenomas relative to normal tissue. Furthermore, TBP expression is positively correlated with VEGFA expression. Collectively, these studies support the idea that increases in TBP expression contribute to enhanced VEGFA transcription early in colorectal cancer development to drive tumorigenesis.