Dual blockade of VEGFR1 and VEGFR2 by a novel peptide abrogates VEGF-driven angiogenesis, tumor growth, and metastasis through PI3K/AKT and MAPK/ERK1/2 pathway

FLT1-enriched extracellular vesicles induce a positive feedback loop between nasopharyngeal carcinoma cells and endothelial cells to promote angiogenesis and tumour metastasis

Distant metastasis is one of the main reasons for treatment failure in nasopharyngeal carcinoma (NPC) patients. Tumour angiogenesis is a key basis for the distant metastasis of NPC. However, the molecular mechanisms underlying the mutual interaction between endothelial and NPC cells in tumour angiogenesis and NPC metastasis are still unclear. Here, we found that extracellular vesicles (EVs) mediate intercellular communication between endothelial cells and NPC cells, thereby promoting NPC cell migration, invasion, colony formation, and angiogenesis. Further experiments indicated that EV-mediated information exchange between endothelial cells and NPC cells upregulated the expression of the vascular endothelial growth factor receptor FLT1 in both types of cells. Mechanistically, FLT1-enriched EVs promoted NPC metastasis through the PI3K/AKT pathway and increased tumour angiogenesis, tumour growth, and distant lung and liver metastasis of NPC in xenografted mice. This effect was achieved through the delivery and upregulation of FLT1 in both endothelial and NPC cells. Thus, our findings reveal that FLT1-enriched EVs induce a positive feedback loop between NPC cells and endothelial cells to promote tumour angiogenesis and tumour metastasis. These results increase our understanding of the intricate interplay between tumour angiogenesis and distant metastasis and have major implications for the diagnosis and management of NPC patients with increased levels of FLT1-enriched EVs.

FDI-6 inhibits VEGF-B expression in metastatic breast cancer: a combined in vitro and in silico study

Angiogenesis is the process by which new blood vessels are formed to meet the oxygen and nutrient needs of tissues. This process is vitally important in many physiological and pathological conditions such as tumor growth, metastasis, and chronic inflammation. Although the relationship of FDI-6 compound with FOXM1 protein is well known in the literature, its relationship with angiogenesis is not adequately elucidated. This study investigates the relationship of FDI-6 with angiogenesis and vascular endothelial growth factor B (VEGF-B) protein expression alterations. Furthermore, the study aims to elucidate the in silico interaction of FDI-6 with the VEGFR1 protein, a key player in initiating the angiogenic process, which is activated through its binding with VEGF-B. Our results demonstrate a significant effect of FDI-6 on cell viability. Specifically, we determined that the IC50 value of FDI-6 in HUVEC cells after 24 h of treatment is 24.2 μM, and in MDA-MB-231 cells after 24 h of application, it is 10.8 μM. These findings suggest that the cytotoxic effect of FDI-6 varies depending on the cell type. In wound healing experiments, FDI-6 significantly suppressed wound closure in MDA-MB-231 cells but did not show a similar effect in HUVEC cells. This finding suggests FDI-6 may have potential cell-type-specific effects. Molecular docking studies reveal that FDI-6 exhibits a stronger interaction with the VEGFR1 protein compared to its inhibitor, a novel interaction not previously reported in the literature. Molecular dynamic simulation results demonstrate a stable interaction between FDI-6 and VEGFR1. This interaction suggests that FDI-6 might modulate mechanisms associated with angiogenesis. Our Western blot analysis results show regulatory effects of FDI-6 on the expression of the VEGF-B protein. We encourage exploration of FDI-6 as a potential therapeutic agent in pathological processes related to angiogenesis. In conclusion, this study provides a detailed examination of the relationship between FDI-6 and both the molecular interactions and protein expressions of VEGF-B. Our findings support FDI-6 as a potential therapeutic agent in pathological processes associated with angiogenesis.

tRF-34-P4R8YP9LON4VHM Promotes Hepatocellular Carcinoma Progression and Tumour Cell-Induced Angiogenesis via the MEK/ERK Pathway

Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer and poses a significant global health challenge. In recent years, tRNA-derived small RNAs (tsRNAs) have gained significant attention due to their potential role in various cancers, including HCC. In this study, we reported that tRF-34-P4R8YP9LON4VHM expression was elevated in HCC tissues and cell lines. The association between tRF-34-P4R8YP9LON4VHM expression and HCC patients' clinicopathological parameters was determined using tissue microarrays of 90 patients, and we found that it was positively associated with the level of AFP, tumour size, microvascular density (MVD), and TNM stage. We performed CCK8, colony formation assay, EdU, cell cycle analysis, transwell assay, and tube formation assay to verify that tRF-34-P4R8YP9LON4VHM could enhance HCC proliferation, migration, invasion, and tumour cell-induced angiogenesis in vitro and in vivo. Mechanistically, tRF-34-P4R8YP9LON4VHM could downregulate DAB2IP expression by directly targeting its 3'-UTR, consequently activating the MEK/ERK signalling pathway and promoting the secretion of VEGFA from HCC cells into the supernatant. In conclusion, our research indicated that tRF-34-P4R8YP9LON4VHM might act as a crucial player in molecular mechanisms and provide novel treatment strategies for HCC patients.

MiR-25-3p regulates pulmonary arteriovenous malformation after Glenn procedure in patients with univentricular heart via the PHLPP2-HIF-1α axis

The detailed mechanism of pulmonary arteriovenous malformations after Glenn surgery (G-PAVMs) in cyanotic congenital heart disease (CHD) remains unclear. Microarray in situ hybridization was performed to assess the miRNA (miRNA) profiles of serum from pediatric patients (0-6 years of age) with G-PAVMs and after the Fontan procedure without G-PAVMs. In addition, we investigated the tube formation, migration, and proliferation of human lung microvascular endothelial cells (HMVEC-L) transfected with miR-25-3p mimic, miR-25-3p inhibitor, or PHLPP2 small interfering RNA, and examined HIF-1α/VEGF-A signaling after hypoxic stimulation. Serum miRNAs that showed ≥ 2-fold higher levels in patients with G-PAVMs than in other patients were selected. MiR-25-3p was significantly upregulated in the pulmonary artery sera of the post-Glenn group than in the post-Fontan group. We identified PHLPP2 as a direct target of miR-25-3p. PHLPP2 expression was significantly decreased in HMVEC-L transfected with miR-25-3p mimic compared to the control cells. HIF-1α and VEGF-A expression levels were increased in HMVEC-L transfected with miR-25-3p mimic compared to the control cells in a PHLPP2/Akt/mTOR signaling-dependent manner after hypoxic stimulation. MiR-25-3p promoted HMVEC-L angiogenesis, proliferation, and migration under hypoxic conditions. MiR-25-3p in the pulmonary arteries may contribute to G-PAVM development.

Synthesis, Radiolabeling, and Biodistribution Study of a Novel DOTA-Peptide for Targeting Vascular Endothelial Growth Factor Receptors in the Molecular Imaging of Breast Cancer

As angiogenesis plays a pivotal role in tumor progression and metastasis, leading to more cancer-related deaths, the angiogenic process can be considered as a target for diagnostic and therapeutic applications. The vascular endothelial growth factor receptor-1 (VEGR-1) and VEGFR-2 have high expression on breast cancer cells and contribute to angiogenesis and tumor development. Thus, early diagnosis through VEGFR-1/2 detection is an excellent strategy that can significantly increase a patient's chance of survival. In this study, the VEGFR1/2-targeting peptide VGB3 was conjugated with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), using 6-aminohexanoic acid (Ahx) as a spacer to prevent steric hindrance in binding. DOTA-Ahx-VGB3 was radiolabeled with Gallium-68 (68Ga) efficiently. An in vitro cell binding assay was assessed in the 4T1 cell line. The tumor-targeting potential of [68Ga]Ga-DOTA-Ahx-VGB3 was conducted for 4T1 tumor-bearing mice. Consequently, high radiochemical purity [68Ga]Ga-DOTA-Ahx-VGB3 (RCP = 98%) was prepared and stabilized in different buffer systems. Approximately 17% of the radiopeptide was internalized after 2 h incubation and receptor binding as characterized by the IC50 value being about 867 nM. The biodistribution and PET/CT studies revealed that [68Ga]Ga-DOTA-Ahx-VGB3 reached the tumor site and was excreted rapidly by the renal system. These features convey [68Ga]Ga-DOTA-Ahx-VGB3 as a suitable agent for the noninvasive visualization of VEGFR-1/2 expression.

Analysis on the pathogenesis and treatment progress of NRG1 fusion-positive non-small cell lung cancer

Lung cancer persistently leads as the primary cause of morbidity and mortality among malignancies. A notable increase in the prevalence of lung adenocarcinoma has become evident in recent years. Although targeted therapies have shown in treating certain subsets of non-small cell lung cancers (NSCLC), a significant proportion of patients still face suboptimal therapeutic outcomes. Neuregulin-1 (NRG1), a critical member of the NRG gene family, initially drew interest due to its distribution within the nascent ventricular endocardium, showcasing an exclusive presence in the endocardium and myocardial microvessels. Recent research has highlighted NRG1's pivotal role in the genesis and progression across a spectrum of tumors, influencing molecular perturbations across various tumor-associated signaling pathways. This review provides a concise overview of NRG1, including its expression patterns, configuration, and fusion partners. Additionally, we explore the unique features and potential therapeutic strategies for NRG1 fusion-positive occurrences within the context of NSCLC.

Chondroitin sulfate-based universal nanoparticle delivers angiogenic inhibitor and paclitaxel to exhibit a combination of chemotherapy and anti-angiogenic therapy

Blocking the tumor nutrient supply through angiogenic inhibitors is an effective treatment approach for malignant tumors. However, using angiogenic inhibitors alone may not be enough to achieve a significant tumor response. Therefore, we recently designed a universal drug delivery system combining chemotherapy and anti-angiogenic therapy to target tumor cells while minimizing drug-related side effects. This system (termed as PCCE) is composed of biomaterial chondroitin sulfate (CS), the anti-angiogenic peptide ES2, and paclitaxel (PTX), which collectively enhance antitumor properties. Interestingly, the PCCE system is conferred exceptional cell membrane permeability due to inherent characteristics of CS, including CD44 receptor-mediated endocytosis. The PCCE could respond to the acidic and high glutathione conditions, thereby releasing PTX and ES2. PCCE could effectively inhibit the proliferation, migration, and invasion of tumor cells and cause apoptosis, while PCCE can affect the endothelial cells tube formation and exert anti-angiogenic function. Consistently, more potent in vivo antitumor efficacy and non-toxic sides were demonstrated in B16F10 xenograft mouse models. PCCE can achieve excellent antitumor activity via modulating angiogenic and apoptosis-related factors. In summary, we have successfully developed an intelligent and responsive CS-based nanocarrier known as PCCE for delivering various antitumor drugs, offering a promising strategy for treating malignant tumors.

Mechanism of Paris polyphylla saponin II inducing autophagic to inhibit angiogenesis of cervical cancer

Paris polyphylla saponin II (PPII) has good biological activity in inhibiting tumor angiogenesis. However, the mechanism of its action is still unclear. This study first observed the inhibitory effect of PPII on cervical cancer cells (Hela) through the establishment of MTT and nude mouse subcutaneous transplantation tumor models. Afterwards, then, we collected Hela cell supernatant for culturing HUVEC cells and treated it with PPII. Observe the invasion, migration, and lumen formation ability of drugs through Transwell, cell scratch test, and angiogenesis experiment. MDC staining was used to observe positive staining in the perinuclear area, AO staining was used to observe acidic areas, and transmission electron microscopy staining was used to observe ultrastructure and autophagy. In addition, the effects of PPII on autophagy- and angiogenesis-related protein expression were detected by Western blotting and quantitative reverse transcriptase polymerase chain reaction. Finally, HUVECs were treated with autophagy inhibitors 3-MA, CQ, and PI3K inhibitor LY294002, respectively. The results showed that the autophagy level of cells treated with PPII was significantly increased. In addition, adding autophagy inhibitors can effectively inhibit angiogenesis in cervical cancer. Further research suggests that PPII induces autophagy in HUVEC cells by regulating the PI3K/AKT/mTOR signaling pathway, thereby affecting angiogenesis and inhibiting Hela cell proliferation, lumen formation, invasion, and migration.

The interaction of platelet-related factors with tumor cells promotes tumor metastasis

Platelets not only participate in thrombosis and hemostasis but also interact with tumor cells and protect them from mechanical damage caused by hemodynamic shear stress and natural killer cell lysis, thereby promoting their colonization and metastasis to distant organs. Platelets can affect the tumor microenvironment via interactions between platelet-related factors and tumor cells. Metastasis is a key event in cancer-related death and is associated with platelet-related factors in lung, breast, and colorectal cancers. Although the factors that promote platelet expression vary slightly in terms of their type and mode of action, they all contribute to the overall process. Recognizing the correlation and mechanisms between these factors is crucial for studying the colonization of distant target organs and developing targeted therapies for these three types of tumors. This paper reviews studies on major platelet-related factors closely associated with metastasis in lung, breast, and colorectal cancers.

SOD3 regulates FLT1 to affect bone metabolism by promoting osteogenesis and inhibiting adipogenesis through PI3K/AKT and MAPK pathways

Osteoporosis is a chronic disease that seriously affects the quality of life and longevity of the elderly, so exploring the mechanism of osteoporosis is crucial for drug development and treatment. Bone marrow mesenchymal stem cells are stem cells with multiple differentiation potentials in bone marrow, and changing their differentiation direction can change bone mass. As an extracellular superoxide dismutase, Superoxide Dismutase 3 (SOD3) has been proved to play an important role in multiple organs, but the detailed mechanism of action in bone metabolism is still unclear. In this study, the results of clinical serum samples ELISA and single cell sequencing chip analysis proved that the expression of SOD3 was positively correlated with bone mass, and SOD3 was mainly expressed in osteoblasts and adipocytes and rarely expressed in osteoblasts in BMSCs. In vitro experiments showed that SOD3 can promote osteogenesis and inhibit adipogenesis. Compared with WT mice, the mice that were knocked out of SOD3 had a significant decrease in bone mineral density and significant changes in related parameters. The results of HE and IHC staining suggested that knocking out SOD3 would lead to fat accumulation in the bone marrow cavity and weakened osteogenesis. Both in vitro and in vivo experiments indicated that SOD3 affects bone metabolism by promoting osteogenesis and inhibiting adipogenesis. The results of transcriptome sequencing and revalidation showed that SOD3 can affect the expression of FLT1. Through in vitro experiments, we proved that FLT1 can also promote osteogenesis and inhibit adipogenesis. In addition, through the repeated experiments, the interaction between the two molecules (SOD3 and FLT1) was verified again. Finally, it was verified by WB that SOD3 regulates FLT1 to affect bone metabolism through PI3K/AKT and MAPK pathways.

Small Molecule Tyrosine Kinase Inhibitors (TKIs) for Glioblastoma Treatment

In the last decade, many small molecules, usually characterized by heterocyclic scaffolds, have been designed and synthesized as tyrosine kinase inhibitors (TKIs). Among them, several compounds have been tested at preclinical and clinical levels to treat glioblastoma multiforme (GBM). GBM is the most common and aggressive type of cancer originating in the brain and has an unfavorable prognosis, with a median survival of 15-16 months and a 5-year survival rate of 5%. Despite recent advances in treating GBM, it represents an incurable disease associated with treatment resistance and high recurrence rates. For these reasons, there is an urgent need for the development of new pharmacological agents to fight this malignancy. In this review, we reported the compounds published in the last five years, which showed promising activity in GBM preclinical models acting as TKIs. We grouped the compounds based on the targeted kinase: first, we reported receptor TKIs and then, cytoplasmic and peculiar kinase inhibitors. For each small molecule, we included the chemical structure, and we schematized the interaction with the target for some representative compounds with the aim of elucidating the mechanism of action. Finally, we cited the most relevant clinical trials.

Antiproliferative Modulation and Pro-Apoptotic Effect of BR2 Tumor-Penetrating Peptide Formulation 2-Aminoethyl Dihydrogen Phosphate in Triple-Negative Breast Cancer

Breast cancer is the most common cancer in women, the so-called "Triple-Negative Breast Cancer" (TNBC) subtype remaining the most challenging to treat, with low tumor-free survival and poor clinical evolution. Therefore, there is a clear medical need for innovative and more efficient treatment options for TNBC. The aim of the present study was to evaluate the potential therapeutic interest of the association of the tumor-penetrating BR2 peptide with monophosphoester 2-aminoethyl dihydrogen phosphate (2-AEH2P), a monophosphoester involved in cell membrane turnover, in TNBC. For that purpose, viability, migration, proliferative capacity, and gene expression analysis of proteins involved in the control of proliferation and apoptosis were evaluated upon treatment of an array of TNBC cells with the BR2 peptide and 2-AEH2P, either separately or combined. Our data showed that, while possessing limited single-agent activity, the 2-AEH2P+BR2 association promoted significant cytotoxicity in TNBC cells but not in normal cells, with reduced proliferative potential and inhibition of cell migration. Mechanically, the 2-AEH2P+BR2 combination promoted an increase in cells expressing p53 caspase 3 and caspase 8, a reduction in cells expressing tumor progression and metastasis markers such as VEGF and PCNA, as well as a reduction in mitochondrial electrical potential. Our results indicate that the combination of the BR2 peptide with 2-AEH2P+BR2 may represent a promising therapeutic strategy in TNBC with potential use in clinical settings.

Vascular endothelial growth factor antagonist peptides inhibit tumor growth and metastasis in breast cancer through repression of c-src and STAT3 genes

BACKGROUND

Breast cancer is one of the most decisive causes of cancer death in women worldwide. Cancer progression and tumor metastasis depend on angiogenesis. Vascular endothelial growth factor (VEGF) and its receptors (VEGFR1 and VEGFR2) are critically required for tumor angiogenesis. Src is involved in many of the VEGF-mediated pathways. The VEGFRs activate Src via different mechanisms. Given that Src activates STAT3 (signal transducers and activators of transcription) repressing apoptosis and promoting the cell cycle, it may be an important object for cancer treatment.

METHODS AND RESULTS

A series of VEGF antagonistic peptides, referred to as VGB 1,3 and 4, were designed to bind and block both VEGFR1 and VEGFR2 inhibiting the proliferation of different tumoral cells. We investigated c-Src and STAT3 gene expression changes in murine 4T1 tumors treated by the VGBs. The treated group received 1 and 10 mg kg-1 of the peptides, while the control mice received PBS, intraperitoneally for two weeks. Both of the groups underwent a resection of breast tissue 14 days after treatment. The results of qRT-PCR showed that the expression levels of c-Src and STAT3 genes were significantly decreased, in a dose-dependent manner, after treatment with the different types of VEGF antagonist peptides, compared to the control groups (P < 0.05). The groups treated with 1 mg kg-1 of all three types of VGB showed decreased expression of c-Src and STAT3 less than the groups receiving 10 mg kg-1 of the anti-angiogenic peptides.

CONCLUSIONS

In conclusion, peptides VGB1, 3, and 4, could be effective therapeutic molecules in breast cancer by inhibiting angiogenesis and progression of the disease.

Solute carrier family 35 member A2 (SLC35A2) is a prognostic biomarker and correlated with immune infiltration in stomach adenocarcinoma

BACKGROUND

Solute carrier family 35 member A2 (SLC35A2) located on the X chromosome is considered involved in the UDP-galactose transport from cytosol to Golgi apparatus and endoplasmic reticulum. It has been reported that the SLC35A2 expression is associated with carcinogenesis in recent studies, however, its specific roles in cancer progression have not been exhaustively elucidated. Herein, a system analysis was conducted to evaluate the role of SLC35A2 in prognostic, and immunology in stomach adenocarcinoma (STAD).

METHODS

The TIMER, GEPIA, UALCAN, Kaplan-Meier Plotter were employed to explore the SLC35A2 expression pattern and prognostic value in STAD. Genomic alterations were searched through the MEXPRESS and cBioPortal platforms. The LinkedOmics, GEPIA and Metascape databases were employed to explore the biological processes. The TIMER and TISIDB websites were utilized to investigate the relationships between SLC35A2 expression and immune cell infiltration. The associations between SLC35A2 expression and tumor mutational burden (TMB), microsatellite instability (MSI) in pan-cancer were explored using the SangerBox database.

RESULTS

Compared to the normal gastric mucosa, SLC35A2 expression was significantly increased in STAD tissues, accompanied by the robust relationships with tumor grade, histological subtypes, TP53 mutation status, TMB and prognosis. SLC35A2 and its co-expression genes played the primarily roles in purine metabolism and purinosome, including the asparagine N-linked glycosylation, protein processing in endoplasmic reticulum, regulation of transcription involved in G1/S transition of mitotic cell cycle, with the potential to participate in the regulation of VEGFA-VEGFR2 signaling pathway. Concurrently, SLC35A2 expression was correlated with macrophages and CD4+T lymphocytes infiltration in STAD.

CONCLUSIONS

Our study has proposed that SLC35A2 correlated with immune cell infiltration could serve as a prognostic biomarker in STAD.

Single-cell and bulk transcriptomics reveals M2d macrophages as a potential therapeutic strategy for mucosal healing in ulcerative colitis

Mucosal healing is essential for treating ulcerative colitis (UC), which results from imbalanced macrophage polarization and dysregulated inflammatory responses. However, the mechanisms of cellular communication and signal transduction that regulate mucosal healing among macrophage subtypes require further investigation. We use bulk and single-cell RNA sequencing analysis to reveal that macrophage subtypes vary in different UC states. At the same time, chemokine and angiogenesis signaling is strongly associated with M2 macrophage's infiltrated proportion. To get more insight into subtypes of macrophages in mucosal healing, we divided macrophages into M1, M2b, and M2d macrophages. Based on the differentially expressed genes (DEGs) between M2d and M1 macrophages, KEGG and GO analysis highlights M2d macrophages' ability to alleviate inflammation and promote epithelial healing. Trajectory analysis revealed opposite differentiation of macrophage subsets between UC and healthy groups, with M1 and M2d macrophages coexisting in the same differentiation branch under UC conditions. Along the pseudotime axis, CCL3 and VEGFA expression increased in UC, while IL10RA remained stable in UC but increased in healthy controls. CellChat identified CCL3-CCR1 has strong communication between M1 and M2d macrophages, while the IL10 signaling pathway is activated explicitly in M2d macrophages to mitigate inflammation and promote epithelial healing. We also speculate that high levels of VEGFA activate endothelial cells expressing VEGFR and worsen inflammation. To conclude, we suggested IL10 and VEGF signaling in M2d macrophages as potential therapeutic targets for mucosal healing. However, it is necessary to establish reliable methods for isolating and purifying M2d macrophages before these targets can be effectively utilized.

A VEGFB-Based Peptidomimetic Inhibits VEGFR2-Mediated PI3K/Akt/mTOR and PLCγ/ERK Signaling and Elicits Apoptotic, Antiangiogenic, and Antitumor Activities

Vascular endothelial growth factor receptor 2 (VEGFR2) mediates VEGFA signaling mainly through the PI3K/AKT/mTOR and PLCγ/ERK1/2 pathways. Here we unveil a peptidomimetic (VGB3) based on the interaction between VEGFB and VEGFR1 that unexpectedly binds and neutralizes VEGFR2. Investigation of the cyclic and linear structures of VGB3 (named C-VGB3 and L-VGB3, respectively) using receptor binding and cell proliferation assays, molecular docking, and evaluation of antiangiogenic and antitumor activities in the 4T1 mouse mammary carcinoma tumor (MCT) model showed that loop formation is essential for peptide functionality. C-VGB3 inhibited proliferation and tubulogenesis of human umbilical vein endothelial cells (HUVECs), accounting for the abrogation of VEGFR2, p-VEGFR2 and, subsequently, PI3K/AKT/mTOR and PLCγ/ERK1/2 pathways. In 4T1 MCT cells, C-VGB3 inhibited cell proliferation, VEGFR2 expression and phosphorylation, the PI3K/AKT/mTOR pathway, FAK/Paxillin, and the epithelial-to-mesenchymal transition cascade. The apoptotic effects of C-VGB3 on HUVE and 4T1 MCT cells were inferred from annexin-PI and TUNEL staining and activation of P53, caspase-3, caspase-7, and PARP1, which mechanistically occurred through the intrinsic pathway mediated by Bcl2 family members, cytochrome c, Apaf-1 and caspase-9, and extrinsic pathway via death receptors and caspase-8. These data indicate that binding regions shared by VEGF family members may be important in developing novel pan-VEGFR inhibitors that are highly relevant in the pathogenesis of angiogenesis-related diseases.

Structure-Based Design of Peptides Targeting VEGF/VEGFRs

Vascular endothelial growth factor (VEGF) and its receptors (VEGFRs) play a main role in the regulation of angiogenesis and lymphangiogenesis. Furthermore, they are implicated in the onset of several diseases such as rheumatoid arthritis, degenerative eye conditions, tumor growth, ulcers and ischemia. Therefore, molecules able to target the VEGF and its receptors are of great pharmaceutical interest. Several types of molecules have been reported so far. In this review, we focus on the structure-based design of peptides mimicking VEGF/VEGFR binding epitopes. The binding interface of the complex has been dissected and the different regions challenged for peptide design. All these trials furnished a better understanding of the molecular recognition process and provide us with a wealth of molecules that could be optimized to be exploited for pharmaceutical applications.

Suppression of Pathological Ocular Neovascularization by a Small Molecular Multi-Targeting Kinase Inhibitor, DCZ19903

Purpose

The administration of anti-vascular endothelial growth factor agents is the standard firs-line therapy for ocular vascular diseases, but some patients still have poor outcomes and drug resistance. This study investigated the role of DCZ19903, a small molecule multitarget kinase inhibitor, in ocular angiogenesis.

Methods

The toxicity of DCZ19903 was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assays, flow cytometry, Calcein-AM/PI staining, and terminal uridine nick-end labeling staining. Oxygen-induced retinopathy and laser-induced choroidal neovascularization models were adopted to assess the antiangiogenic effects of DCZ19903 by Isolectin B4 (GS-IB4) and hematoxylin-eosin staining. EdU assays, transwell migration assays, tube formation, and choroid sprouting assays were performed to determine the antiangiogenic effects of DCZ19903. The antiangiogenic mechanism of DCZ19903 was determined using network pharmacology approach and western blots.

Results

There was no obvious cytotoxicity or tissue toxicity after DCZ19903 treatment. DCZ19903 exerted the antiangiogenic effects in OIR model and choroidal neovascularization model. DCZ19903 inhibited the proliferation, tube formation, migration ability of endothelial cells, and choroidal explant sprouting. DCZ19903 plus ranibizumab achieved greater antiangiogenetic effects than DCZ19903 or ranibizumab alone. DCZ19903 exerted its antiangiogenic effects via affecting the activation of ERK1/2 and p38 signaling.

Conclusions

DCZ19903 is a promising drug for antiangiogenic treatment in ocular vascular diseases.

Translational Relevance

These findings suggest that DCZ19903 possesses great antiangiogenic potential for treating ocular vascular diseases.

Targeting Vascular endothelial growth factor A with soluble vascular endothelial growth factor receptor 1 ameliorates nerve injury-induced neuropathic pain

Neuropathic pain is a distressing medical condition with few effective treatments. The role of Vascular endothelial growth factor A (VEGFA) in inflammation pain has been confirmed in many researches. However, the mechanism of VEGFA affects neuropathic pain remains unclear. In this study, we demonstrated that VEGFA plays an important role in spare nerve injury (SNI)-induced neuropathic pain, which is mediated by enhanced expression and colocalized of VEGFA, p-AKT and TRPV1 in SNI-induced neuropathic pain model. Soluble VEGFR1 (sFlt1) not only relieved mechanical hyperalgesia and the expression of inflammatory markers, but ameliorated the expression of VEGFA, VEGFR2, p-AKT, and TRPV1 in spinal cord. However, these effects of sFlt1 can be blocked by rpVEGFA and by 740 Y-P. Therefore, our study indication that targeting VEGFA with sFlt1 reduces neuropathic pain development via the AKT/TRPV1 pathway in SNI-induced nerve injury. This study elucidates a new therapeutic target for neuropathic pain.

The reversal of anti-HER2 resistance in advanced HER2-positive breast cancer using apatinib: two cases reports and literature review

BACKGROUND

Human epidermal growth factor receptor 2 (HER2)-targeted treatment has yielded a notable clinical benefit in patients with HER2-positive breast cancer. However, nearly 50% of patients still suffer disease progression due to resistance to HER2-targeted therapy. After the failure of macromolecular monoclonal antibodies (mAbs) therapy, we can choose small molecule tyrosine kinase inhibitors (TKIs) to reverse HER2 resistance. When small molecule TKIs resistance, we can use mAb combined with small molecule TKI, or antibody-drug conjugates (ADCs) to reverse HER2 resistance. However, then due to the availability and price of ADCs, patients may not use them. Consequently, new therapeutic approaches are required to overcome HER2-targeted therapy resistance. Vascular endothelial growth factor and its receptors (VEGF/VEGFRs) promote tumor angiogenesis. They can also activate downstream signaling pathways to promote tumorigenesis. VEGFR is a key regulator of the tyrosine kinase signaling pathway and may be a potential target in HER2-positive breast cancer. Apatinib is a small molecule TKI that specifically binds to VEGFR2 and thus exerts an antitumor effect. Although there is no definite indication for apatinib in breast cancer, it has a good benefit in advanced gastric cancer.

CASE DESCRIPTION

The two patients we reported were both HER2-positive breast cancer who we followed for more than 10 years. After the failure of multi-line anti-HER2 treatment, apatinib combined with anti-HER2 treatment had PFS of 8.4 months and 10.6 months, respectively. One patient had grade 2 hand-foot syndrome. The other had grade 2 leukopenia and grade 2 thrombocytopenia, both of them improved after control. And the best response of them were PR and SD, respectively.

CONCLUSIONS

Our cases demonstrate that, in HER2-positive breast cancer patients with HER2-targeted resistance, apatinib may be able to reverse HER2 resistance. These two cases suggest an alternative method for clinical HER2-targeted treatment of drug-resistant breast cancer patients and provide new insights for future research.

A Potential Anticancer Mechanism of Finger Root (Boesenbergia rotunda) Extracts against a Breast Cancer Cell Line

Breast cancer is the most common type of cancer women suffer from worldwide in 2020 and the 4th leading cause of cancer death. Boesenbergia rotunda is an herb with high potential as an anticancer agent. This study explores the potential bioactive compounds in B. rotunda as anti-breast cancer agents using in silico and in vitro approaches. The in silico study was used for active compound analysis, selection of anticancer compound candidates, prediction of target protein, functional annotation, molecular docking, and molecular dynamics simulation, respectively. The in vitro study was conducted by measurement toxicity, rhodamine 123, and apoptosis assays on T47D cells. Based on the KNApSAcK database, B. rotunda contained 20 metabolites, which are dominated by chalcone and flavonoid groups. Seven of them were predicted to have anticancer activity, namely, sakuranetin, cardamonin, alpinetin, 2S-pinocembrin, 7.4'-dihydroxy-5-methoxyflavanone, 5.6-dehydrokawain, and pinostrobin chalcone. These compounds targeted proteins related to cancer progression pathways such as the PI3K/Akt, FOXO, JAK/STAT, and estrogen signaling pathways. Therefore, these compounds are predicted to inhibit growth and induce apoptosis of cancer cells through their interactions with MMP12, MMP13, CDK4, JAK3, VEGFR1, VEGFR2, and KCNA3. Anticancer activity of B. rotunda through in vitro study confirmed that B. rotunda extract is strong cytotoxic and induces apoptosis of breast cancer cell lines. This study concludes that Boesenbergia rotunda has potency as an anticancer candidate.

Small biomarkers with massive impacts: PI3K/AKT/mTOR signalling and microRNA crosstalk regulate nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumours of the head and neck in Southeast Asia and southern China. The Phosphatidylinositol 3-kinase/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signalling pathway is involved in processes related to tumour initiation/progression, such as proliferation, apoptosis, metastasis, and drug resistance, and is closely related to the clinicopathological features of NPC. In addition, key genes involved in the PI3K/AKT/mTOR signalling pathway undergo many changes in NPC. More interestingly, a growing body of evidence suggests an interaction between this signalling pathway and microRNAs (miRNAs), a class of small noncoding RNAs. Therefore, in this review, we discuss the interactions between key components of the PI3K/AKT/mTOR signalling pathway and various miRNAs and their importance in NPC pathology and explore potential diagnostic biomarkers and therapeutic targets.

Anti-tumor and anti-metastatic activity of the FGF2 118-126 fragment dependent on the loop structure

Fibroblast Growth Factor /FGF Receptor 1 (FGF2/FGFR1) system regulates the growth and metastasis of different cancers. Inhibition of this signaling pathway is an attractive target for cancer therapy. Here, we aimed to reproduce the 118-126 fragment of FGF2 to interfere with the FGF2-FGFR1 interaction. To determine whether the loop structure affects the function of this fragment, we compared cyclic (disulfide-bonded) and linear peptide variants. The cyclic peptide (referred to as BGF1) effectively inhibited the FGF2-induced proliferation of HUVECs, 4T1 mammary carcinoma, U87 glioblastoma, and SKOV3 ovarian carcinoma cells. It led to apoptosis induction in HUVECs, whereas the linear peptide (referred to as BGF2) was ineffective. In a murine 4T1 tumor model, BGF1 inhibited tumor growth more effectively than Avastin and increased animals' survival without causing weight loss, but the linear peptide BGF2 had no significant anti-tumor effects. According to immunohistochemical studies, the anti-tumor properties of BGF1 were associated with suppression of tumor cell proliferation (Ki-67 expression), angiogenesis (CD31 expression), and apoptosis induction (as was shown by increased p53 expression and TUNEL staining and decreased Bcl-2 expression). The potential of BGF1 to suppress tumor invasion was indicated by quantitative analysis of the metastasis-related proteins, including FGFR1, pFGFR1, NF-κB, p-NF-κB, MMP-9, E-cadherin, N-cadherin, and Vimentin, and supported by small animal positron emission tomography (PET) used 18Fluorodeoxyglucose (18F-FDG). These results demonstrate that the functional properties of the 118-126 region of FGF2 depend on the loop structure and the peptide derived from this fragment encourages further preclinical investigations.

Astrocytes Protect Human Brain Microvascular Endothelial Cells from Hypoxia Injury by Regulating VEGF Expression

Hypoxic-ischemic stroke has been associated with changes in neurovascular behavior, mediated, in part, by induction of the vascular endothelial growth factor (VEGF). The objective of this study was to investigate the effects of human astrocytes on the proliferation, apoptosis, and function of human microvascular endothelial cells (hBMEC) in vitro. Human microvascular endothelial cells (hBMEC) and human normal astrocytes (HA-1800) were used to establish in vitro cocultured cell models. The coculture model was used to simulate hypoxic-ischemic stroke, and it was found that astrocytes could promote hBMEC proliferation, inhibit apoptosis, reduce cell damage, and enhance antioxidant capacity by activating the VEGF signaling pathway. When VEGF is knocked out in astrocytes, the protective effect of astrocytes on hBMEC was partially lost. In conclusion, our study confirms the protective effect of hBMEC and laid a foundation for the study of hypoxic-ischemic stroke.

Synthetic Peptides That Antagonize the Angiotensin-Converting Enzyme-2 (ACE-2) Interaction with SARS-CoV-2 Receptor Binding Spike Protein

The SARS-CoV-2 viral spike protein S receptor-binding domain (S-RBD) binds ACE2 on host cells to initiate molecular events, resulting in intracellular release of the viral genome. Therefore, antagonists of this interaction could allow a modality for therapeutic intervention. Peptides can inhibit the S-RBD:ACE2 interaction by interacting with the protein-protein interface. In this study, protein contact atlas data and molecular dynamics simulations were used to locate interaction hotspots on the secondary structure elements α1, α2, α3, β3, and β4 of ACE2. We designed a library of discontinuous peptides based upon a combination of the hotspot interactions, which were synthesized and screened in a bioluminescence-based assay. The peptides demonstrated high efficacy in antagonizing the SARS-CoV-2 S-RBD:ACE2 interaction and were validated by microscale thermophoresis which demonstrated strong binding affinity (∼10 nM) of these peptides to S-RBD. We anticipate that such discontinuous peptides may hold the potential for an efficient therapeutic treatment for COVID-19.

Inhibitory Effect of Ursolic Acid on the Migration and Invasion of Doxorubicin-Resistant Breast Cancer

The cause of death in most breast cancer patients is disease metastasis and the occurrence of multidrug resistance (MDR). Ornithine decarboxylase (ODC), which is involved into multiple pathways, is closely related to carcinogenesis and development. Ursolic acid (UA), a natural triterpenoid compound, has been shown to reverse the MDR characteristics of tumor cells. However, the effect of UA on the invasion and metastasis of tumor cells with MDR is not known. Therefore, we investigated the effects of UA on invasion and metastasis, ODC-related polyamine metabolism, and MAPK-Erk-VEGF/MMP-9 signaling pathways in a doxorubicin-resistant breast cancer cell (MCF-7/ADR) model. The obtained results showed that UA significantly inhibited the adhesion and migration of MCF-7/ADR cells, and had higher affinities with key active cavity residues of ODC compared to the known inhibitor di-fluoro-methyl-ornithine (DFMO). UA could downregulate ODC, phosphorylated Erk (P-Erk), VEGF, and matrix metalloproteinase-9 (MMP-9) activity. Meanwhile, UA significantly reduced the content of metabolites of the polyamine metabolism. Furthermore, UA increased the intracellular accumulation of Dox in MCF-7/ADR cells. Taken together, UA can inhibit against tumor progression during the treatment of breast cancer with Dox, and possibly modulate the Erk-VEGF/MMP-9 signaling pathways and polyamine metabolism by targeting ODC to exert these effects.

Apoptosis induction in human lung and colon cancer cells via impeding VEGF signaling pathways

There is ample evidence to suggest that vascular endothelial growth factor (VEGF) is a potent mitogen factor in vasculogenesis and angiogenesis and that blockade of VEGF-mediated signals can also prevent tumor growth via enforcing cell apoptosis. In the current study, we assessed the suppressing effect of VGB4, a VEGF antagonist peptide with the binding ability to both VEGF receptor1 and VEGF receptor2, on VEGF-induced proliferation and migration of the human lung adenocarcinoma cell line A549 and the human colon adenocarcinoma cell line HT29 using MTT assay, colony formation assay, and Scratch-wound assay. To evaluate the apoptotic inductive effect of VGB4 on A549 and HT29 cells, apoptosis analysis was carried out by flow cytometry and TUNEL assay. Likewise, p53 and PTEN expression level was examined by immunofluorescence microscopy. In addition, the level of proteins involved in VEGF signaling pathways related to apoptosis was investigated using western blot analysis. Our results indicated that VGB4 markedly inhibited VEGF-induced proliferation and migration, and induced apoptosis of A549 and HT29 cells dose dependently. Encouragingly, significant downregulation of B-cell lymphoma 2 (Bcl2), X-linked inhibitor of apoptosis, Procaspase9, and procaspase3, as well as upregulation of PTEN and P53 tumor suppressors, BCL2 associated X, Cytochrome c, cleaved caspase9, and cleaved caspase3 in VGB4-treated A549 and HT29 cells, further confirmed the profound inductive influence of VGB4 on apoptotic pathways. These findings along with the results from our previous studies show that VGB4 may be considerable for cancer therapy.

Conjugation of VEGFR1/R2-targeting peptide with gold nanoparticles to enhance antiangiogenic and antitumoral activity

BACKGROUND

Inhibition of tumor angiogenesis through simultaneous targeting of vascular endothelial growth factor receptor (VEGFR)-1 and -2 is highly efficacious. An antagonist peptide of VEGFA/VEGFB, referred to as VGB3, can recognize and neutralize both VEGFR1 and VEGFR2 on the endothelial and tumoral cells, thereby inhibits angiogenesis and tumor growth. However, improved efficacy and extending injection intervals is required for its clinical translation. Given that gold nanoparticles (GNPs) can enhance the efficacy of biotherapeutics, we conjugated VGB3 to GNPs to enhance its efficacy and extends the intervals between treatments without adverse effects.

RESULTS

GNP-VGB3 bound to VEGFR1 and VEGFR2 in human umbilical vein endothelial (HUVE) and 4T1 mammary carcinoma cells. GNP-VGB3 induced cell cycle arrest, ROS overproduction and apoptosis and inhibited proliferation and migration of endothelial and tumor cells more effectively than unconjugated VGB3 or GNP. In a murine 4T1 mammary carcinoma tumor model, GNP-VGB3 more strongly than VGB3 and GNP inhibited tumor growth and metastasis, and increased animal survival without causing weight loss. The superior antitumor effects were associated with durable targeting of VEGFR1 and VEGFR2, thereby inhibiting signaling pathways of proliferation, migration, differentiation, epithelial-to-mesenchymal transition, and survival in tumor tissues. MicroCT imaging and inductively coupled plasma mass spectrometry showed that GNP-VGB3 specifically target tumors and exhibit greater accumulation within tumors than the free GNPs.

CONCLUSION

Conjugation to GNPs not only improved the efficacy of VGB3 peptide but also extended the intervals between treatments without adverse effects. These results suggest that GNP-VGB3 is a promising candidate for clinical translation.

Combination of ShuangDan Capsule and Sorafenib Inhibits Tumor Growth and Angiogenesis in Hepatocellular Carcinoma Via PI3K/Akt/mTORC1 Pathway

Hepatocellular carcinoma (HCC) is a high mortality liver cancer. The existing treatments (transplantation, chemotherapy, and individualized treatment) with limitations. However, drug combination provides a viable option for hepatocellular carcinoma treatment. A Chinese patent medicine, ShuangDan Capsules (SDC), has been clinically prescribed to hepatocellular carcinoma patients as adjuvant therapy and has shown good antitumor activity. The purpose of this study was to investigate whether SDC could improve the anti-cancer effect and mitigate adverse reactions of sorafenib on HCC in vivo. Magnetic resonance imaging (MRI), immunohistochemistry, and western blot were executed to reveal the potential mechanisms of the combination of SDC and sorafenib on HCC. Tumors appeared hyperintense on T2 sequence images relative to the adjacent normal liver in MRI. Combination of SDC and sorafenib inhibited the progression of DEN (Diethylnitrosamine)-induced HCC. In the HepG2 xenografts model, sorafenib plus SDC exhibited greater suppression on tumor growth than individual treatment accompanied with decreased expression of VEGF, VEGFA, Ki67, CD31 and increased expression of caspase-3. Furthermore, PI3K/Akt/mTORC1 pathway was inhibited by co-administration. Sorafenib monotherapy elicited hepatotoxicity for specific expression in the up-regulated level of aspartate transaminase (AST) and AST/glutamic-pyruvic transaminase (ALT) ratio, but the co-administration could remedy this adverse effect. These dates indicated that the combination of SDC and sorafenib might offer a potential therapy for HCC.

Crosstalk between miRNA and PI3K/AKT/mTOR signaling pathway in cancer

Phosphoinositide-3 kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway is one of the most important proliferative signaling pathways with critical undeniable function in various aspects of cancer initiation/progression, including proliferation, apoptosis, metastasis, angiogenesis, and drug resistance. On the other hand, numerous genetic alterations in the key genes involved in the PI3K/AKT/mTOR signaling pathway have been identified in multiple solid and hematological tumors. In addition, accumulating recent evidences have demonstrated a reciprocal interaction between this signaling pathway and microRNAs, a large group of small non-coding RNAs. Therefore, in this review, it was attempted to discuss about the interaction between key components of PI3K/AKT/mTOR signaling pathway with various miRNAs and their importance in cancer biology.

A Cyclic Peptide Epitope of an Under-Explored VEGF-B Loop 1 Demonstrated In Vivo Anti-Angiogenic and Anti-Tumor Activities

Pathological angiogenesis is mainly initiated by the binding of abnormal expressed vascular endothelial growth factors (VEGFs) to their receptors (VEGFRs). Blocking the VEGF/VEGFR interaction is a clinically proven treatment in cancer. Our previous work by epitope scan had identified cyclic peptides, mimicking the loop 1 of VEGF-A, VEGF-B and placental growth factor (PlGF), inhibited effectively the VEGF/VEGFR interaction in ELISA. We described here the docking study of these peptides on VEGFR1 to identify their binding sites. The cellular anti-angiogenic activities were examined by inhibition of VEGF-A induced cell proliferation, migration and tube formation in human umbilical vein endothelial cells (HUVECs). The ability of these peptides to inhibit MAPK/ERK1/2 signaling pathway was examined as well. On chick embryo chorioallantoic membrane (CAM) model, a cyclic peptide named B-cL1 with most potent in vitro activity showed important in vivo anti-angiogenic effect. Finally, B-cL1 inhibited VEGF induced human gastric cancer SGC-7901 cells proliferation. It showed anti-tumoral effect on SGC-7901 xenografted BALB/c nude mouse model. The cyclic peptides B-cL1 constitutes an anti-angiogenic peptide drug lead for the design of new and more potent VEGFR antagonists in the treatment of angiogenesis related diseases.

EIF3D promotes the progression of preeclampsia by inhibiting of MAPK/ERK1/2 pathway

Preeclampsia (PE) has been recognized as one of the main reasons for neonatal and maternal mortality and morbidity. This study intended to identify certain genes that correlated with the pathogenesis of PE, and disclose the underlying mechanisms. The GSE14776 and GSE65271 datasets were obtained from the Gene Expression Omnibus database. Venn diagram analysis was performed to identify the differently expressed genes. The potential pathways were analyzed by Gene set enrichment analysis software. The expression of eukaryotic translation initiation factor 3 subunit D (EIF3D) in tissues and cells was respectively tested by immunohistochemistry and the quantitative real-time PCR. Cell transfection was utilized to alter the expression of EIF3D. Cell proliferation, invasion and migration were respectively tested by MTT, EdU, transwell and wound healing assays. Tube formation assay was utilized to determine the tube formation capacity of HTR-8/SVneo cells. ELISA was employed for determination of the concentration of Angiotensin (ANG)-1. Moreover, the expression of EIF3D, proliferation-, metastasis-, tube formation- and MAPK/ERK1/2 pathway-related proteins were measured utilizing western blot. EIF3D was selected in this study. EIF3D was upregulated in placentas tissues collected from patients with PE. EIF3D upregulation observably repressed the proliferation, invasion, migration, wound healing and tube formation of HTR-8/SVneo cells, and the expression of their associated proteins. Besides, the concentration of ANG-1, and the ratios of phosphorylated-ERK1/2 and phosphorylated-MEK1/MEK1 were also markedly lowered by EIF3D upregulation. Whereas, EIF3D knockdown exerted the opposite effects, and these effects were distinctly counteracted by ERK1/2 inhibitor SC-221593 treatment. In conclusion, these observations manifested that EIF3D upregulation might have repressed the progression of PE through modulation of MAPK/ERK1/2 pathway.

Curcumin in Combination With Omacetaxine Suppress Lymphoma Cell Growth, Migration, Invasion, and Angiogenesis via Inhibition of VEGF/Akt Signaling Pathway

Background

Both omacetaxine (HHT) and curcumin were shown to exhibit anti-proliferative effect on lymphoma cells. However, the role of combination of HHT with curcumin (HHT/curcumin combination) on lymphoma cells remains unclear. Thus, this study aimed to investigate the effect of HHT/curcumin combination on the proliferation, migration, and angiogenesis of lymphoma cells.

Methods

Cell counting kit-8 (CCK-8), Ki67 immunofluorescence and transwell assays were used to assess the viability, proliferation and migration of U937 and Raji cells respectively. In addition, tube formation assay was used to determine the effects of HHT/curcumin combination on angiogenesis in human umbilical vein endothelial cells (HUVECs).

Results

In this study, we found that HHT/curcumin combination significantly inhibited the proliferation, migration and invasion in U937 and Raji cells (all P < 0.01). In addition, combination treatment markedly inhibited the secreted levels of vascular endothelial growth factor (VEGF)-(A-D) (all P < 0.01) in Raji cells. Moreover, combination treatment exhibited anti-tumor effects in Raji cells, as shown by the decreased signals of phosphorylated VEGF receptor 2 (p-VEGFR2) and phosphorylated protein kinase B (p-Akt) (all P < 0.01). Meanwhile, combination treatment inhibited VEGFA levels (P < 0.01) in exosomes derived from Raji cells. Application of exosomes with downregulated VEGF to HUVECs notably inhibited proliferation, migration and tube formation of HUVECs, evidenced by the decreased signals of p-Akt, angiogenin-1, matrix metallopeptidase 2 (MMP2) and matrix metallopeptidase 9 (MMP9) (all P < 0.01).

Conclusion

Our findings indicated that combination of HHT and curcumin could inhibit lymphoma cell growth and angiogenesis via inhibition of VEGF/Akt signaling pathway. These results suggested that HHT combined with curcumin might be regarded as a promising therapeutic approach for the treatment of lymphoma.

Geniposide downregulates the VEGF/SphK1/S1P pathway and alleviates angiogenesis in rheumatoid arthritis in vivo and in vitro

The VEGF/SphK1/S1P pathway is closely related to angiogenesis in rheumatoid arthritis (RA), but the precise underlying mechanisms are unclear at present. Here, we explored the involvement of the VEGF/SphK1/S1P cascade in RA models and determined the effects of GE intervention. Our results showed abnormal expression of proteins related to this pathway in RA synovial tissue. Treatment with GE effectively regulated the signal axis, inhibited angiogenesis, and alleviated RA symptoms. In vitro, TNF-ɑ enhanced the VEGF/SphK1/S1P pathway in a co-culture model of fibroblast-like synoviocytes (FLS) and vascular endothelial cells (VEC). GE induced downregulation of VEGF in FLS, restored the dynamic balance of pro-/antiangiogenic factors, and suppressed SphK1/S1P signaling in VEC, resulting in lower proliferation activity, migration ability, tube formation ability, and S1P secretion ability of VEC cells. Additionally, SphK1-specific small interfering RNA (siRNA) blocked the VEGF/SphK1/S1P cascade, which can effectively alleviate the stimulatory effect of FLS on VEC and further enhanced the therapeutic effect of GE. Taken together, our results demonstrate that GE suppresses the VEGF/SphK1/S1P pathway and alleviates the stimulation of VEC by FLS, thereby preventing angiogenesis and promoting therapeutic effects against RA.

LncRNA MALAT1 inhibits hypoxia/reoxygenation-induced human umbilical vein endothelial cell injury via targeting the microRNA-320a/RAC1 axis

Angiogenesis is believed to protect against hypoxia/reoxygenation (H/R)-induced cell injury. MALAT1 and microRNA-320a (miR-320a) are involved in cancer angiogenesis. To investigate the function of the MALAT1/miR-320a axis in H/R-induced cell injury, human umbilical vein endothelial cell (HUVEC) angiogenesis was detected using the Cell Counting Kit-8 (CCK-8), Transwell migration, cell adhesion and tube formation assays. The expression of MALAT1 and miR-320a was revealed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The direct binding relationship between miR-320a and MALAT1 was detected by RNA immunoprecipitation (RIP) and dual luciferase reporter assays. The data indicated that H/R induces angiogenesis injury and that the expression of MALAT1 was augmented in H/R-stimulated HUVECs. Overexpression of MALAT1 alleviated H/R-stimulated HUVEC dysfunction, whereas silencing of MALAT1 exerted the opposite effects. MALAT1 also reduced miR-320a levels in HUVECs. Overexpression of miR-320a repressed the function of MALAT1 on H/R-stimulated HUVECs, whereas inhibition of miR-320a exerted the opposite effect. Additionally, miR-320a inhibition alleviated H/R-stimulated HUVEC injury via RAC1. Taken together, this investigation concluded that MALAT1 represses H/R-stimulated HUVEC injury by targeting the miR-320a/RAC1 axis.

Third-generation EGFR inhibitor HS-10296 in combination with famitinib, a multi-targeted tyrosine kinase inhibitor, exerts synergistic antitumor effects through enhanced inhibition of downstream signaling in EGFR-mutant non-small cell lung cancer cells

BACKGROUND

As a highly heterogeneous disease, lung cancer has a multitude of cellular components and patterns of gene expression which are not dependent on a single mutation or signaling pathway. Thus, using combined drugs to treat lung cancer may be a practical strategy.

METHODS

The combined antitumor effects of HS-10296, a third-generation EGFR inhibitor targeting EGFR T790M mutation, with the multitargeted tyrosine kinase inhibitor (TKI) famitinib in non-small cell lung cancer (NSCLC) were evaluated by in vitro methods such as cell proliferation, apoptosis, angiogenesis assays, and in vivo animal efficacy studies.

RESULTS

Famitinib strengthened the effects of HS-10296 on inhibiting proliferation and inducing apoptosis of NSCLC cells, possibly by synergistic inhibition of AKT and ERK phosphorylation. Meanwhile, HS-10296 significantly potentiated the effects of famitinib on inhibiting the proliferation and migration of HUVEC, which may be through synergistic inhibition of ERK phosphorylation in HUVEC, suggesting that HS-10296 may improve the inhibition of angiogenesis by famitinib. Moreover, combination of HS-10296 and famitinib exerted synergistic antitumor activity in NCI-H1975 and PC-9 xenograft models, and this effect may be accomplished by synergistic inhibition of phosphorylation of AKT and ERK and tumor angiogenesis in tumor tissues.

CONCLUSIONS

Collectively, our results indicate that HS-10296 and famitinib exhibit significant synergistic antitumor activity, suggesting that the third-generation EGFR inhibitor combined with VEGFR inhibitor provides a promising strategy in the treatment of EGFR-mutant NSCLC.

FBXW7 inhibits invasion, migration and angiogenesis in ovarian cancer cells by suppressing VEGF expression through inactivation of β-catenin signaling

F-box and WD repeat domain containing 7 (FBXW7) is a tumor suppressor gene frequently inactivated in several human malignancies. The present study aimed to investigate the role of FBXW7 in the invasion, migration and angiogenesis of ovarian cancer (OC) cells, and to identify its potential molecular mechanisms. First, the expression levels of FBXW7 and vascular endothelial growth factor (VEGF) were detected in several human OC cell lines using western blotting. Subsequently, FBXW7 was overexpressed to determine VEGF expression in SKOV3 cells. Transwell, wound healing and tube formation assays were performed following transfection with FBXW7 and VEGF overexpression plasmids to assess invasion, migration and angiogenesis in SKOV3 cells, respectively. Western blot analysis was performed to detect the expression levels of epithelial-to-mesenchymal transition and angiogenesis-associated proteins. In addition, the expression levels of β-catenin and c-Myc were assessed, and lithium chloride (LiCl), an agonist of β-catenin signaling, was used to elucidate the molecular mechanisms by which FBXW7 mediates its antitumor activity in OC. The results demonstrated that FBXW7 expression was markedly downregulated, whilst VEGF expression was markedly upregulated in OC cell lines compared with that in normal ovarian cells. Overexpression of FBXW7 significantly decreased VEGF expression in SKOV3 cells. Notably, overexpression of VEGF reversed the inhibitory effects of FBXW7 overexpression on the invasion, migration and angiogenesis of OC cells, accompanied by upregulated expression levels of N-cadherin, slug, CD31, VEGF receptor 1 (VEGFR1) and VEGFR2, and downregulated expression levels of E-cadherin. Furthermore, overexpression of FBXW7 markedly suppressed β-catenin and c-Myc expression, whereas the decreased expression levels of VEGF, VEGFR1 and VEGFR2 following overexpression of FBXW7 were increased after treatment of SKOV3 cells with LiCl. Overall, the results of the present study suggested that FBXW7 inhibited invasion, migration and angiogenesis of OC cells by suppressing VEGF expression through inactivation of β-catenin signaling. Thus, FBXW7 may be used as a novel therapeutic target for the treatment of OC.

Construction of competitive endogenous RNA network reveals regulatory role of long non-coding RNAs in intracranial aneurysm

BACKGROUND

Rupture of intracranial aneurysm (IA) is the main cause of devastating subarachnoid hemorrhage, which urges our understanding of the pathogenesis and regulatory mechanisms of IA. However, the regulatory roles of long non-coding RNAs (lncRNAs) in IA is less known.

RESULTS

We processed the raw SRR files of 12 superficial temporal artery (STA) samples and 6 IA samples to count files. Then the differentially expressed (DE) mRNAs, miRNAs, and lncRNAs between STAs and IAs were identified. The enrichment analyses were performed using DEmRNAs. Next, a lncRNA-miRNA-mRNA regulatory network was constructed using integrated bioinformatics analysis. In summary, 341 DElncRNAs, 234 DEmiRNAs, and 2914 DEmRNAs between the STA and IA. The lncRNA-miRNA-mRNA regulatory network of IA contains 91 nodes and 146 edges. The subnetwork of hub lncRNA PVT1 was extracted. The expression level of PVT1 was positively correlated with a majority of the mRNAs in its subnetwork. Moreover, we found that several mRNAs (CCND1, HIF1A, E2F1, CDKN1A, VEGFA, COL1A1 and COL5A2) in the PVT1 subnetwork served as essential components in the PI3K-Akt signaling pathway, and that some of the non-coding RNAs (ncRNAs) (PVT1, HOTAIR, hsa-miR-17, hsa-miR-142, hsa-miR-383 and hsa-miR-193b) interacted with these mRNAs.

CONCLUSION

Our annotations noting ncRNA's role in the pathway may uncover novel regulatory mechanisms of ncRNAs and mRNAs in IA. These findings provide significant insights into the lncRNA regulatory network in IA.

Effect of Babao Dan on angiogenesis of gastric cancer in vitro by regulating VEGFA/VEGFR2 signaling pathway

BACKGROUND

To further elucidate the anti-angiogenesis effect of Babao Dan (BBD) in vitro, gastric cancer (GC) cells and human umbilical vein endothelial cells (HUVECs) were used to evaluate the regulation role of BBD by vascular endothelial growth factor A (VEGFA)/vascular endothelial growth factor receptor 2 (VEGFR2) signaling pathway.

METHODS

After induced by VEGFA, GC cells (AGS, MGC80-3 and BGC823) were treated by different concentrations of BBD and then were detected cell viability, migration and VEGFA level. And the anti-angiogenesis effect of BBD was evaluated with HUVECs. To furtherly mimic the tumor microenvironment of angiogenesis, VEGFA as an inducer (10 ng/mL) was used to trigger a cascade of angiogenesis of HUVECs in vitro.

RESULTS

The viability and migration of GC cells with VEGFA-induced or non-induced and VEGFA levels in GC cells were significantly inhibited by BBD with concentration-dependent manner (P<0.01). BBD significantly inhibited the HUVECs viability with concentration-dependent manner (P<0.01), which was consistent with the inhibitory action on augmentation of cell viability induced by VEGFA (P<0.01). BBD exhibited the similar inhibitory trend on cyto behavioral variability such as wound repairing (P<0.05), migration (P<0.01) and tube formation (P<0.01) and activation effect on cell apoptosis rate (P<0.01) with VEGFA-induced or non-induced. Moreover, BBD notably regulated the levels of VEGFA, VEGFR2, matrix metalloprotein 2 (MMP2) and matrix metalloprotein 9 (MMP9) of HUVECs on present or absent of VEGFA with dose-dependent manner.

CONCLUSIONS

BBD inhibited GC growth against VEGFA-induced angiogenesis of HUVECs by VEGFA/VEGFR2 signaling pathway in vitro.

Considering both small and large scale motions of vascular endothelial growth factor (VEGF) is crucial for reliably predicting its binding affinities to DNA aptamers

Considering both small and large scale motions of VEGF is crucial to predict its relative binding affinities to DNA aptamer variants with docking.

Pathological angiogenesis and inflammation in tissues

The role of angiogenesis in the growth of organs and tumors is widely recognized. Vascular-organ interaction is a key mechanism and a concept that enables an understanding of all biological phenomena and normal physiology that is essential for human survival under pathological conditions. Recently, vascular endothelial cells have been classified as a type of innate immune cells that are dependent on the pathological situations. Moreover, inflammatory cytokines and signaling regulators activated upon exposure to infection or various stresses play crucial roles in the pathological function of parenchymal cells, peripheral immune cells, stromal cells, and cancer cells in tissues. Therefore, vascular-organ interactions as a vascular microenvironment or tissue microenvironment under physiological and pathological conditions are gaining popularity as an interesting research topic. Here, we review vascular contribution as a major factor in microenvironment homeostasis in the pathogenesis of normal as well as cancerous tissues. Furthermore, we suggest that the normalization strategy of pathological angiogenesis could be a promising therapeutic target for various diseases, including cancer.

Veettil V, Noumi E, A. Al-Motair K, Aouadi K, Kadri A, De Feo V, Snoussi M. Allium subhirsutum L. as a Potential Source of Antioxidant and Anticancer Bioactive Molecules: HR-LCMS Phytochemical Profiling, In Vitro and In Vivo Pharmacological Study

This study investigated Allium subhirsutum L. (AS) anticancer and antioxidant effects and inhibition of tumor angiogenesis in a murine model of skeletal metastases due to inoculation of Walker 256/B cells. Phytochemical composition of AS extract (ASE) was studied by High Resolution-Liquid Chromatography Mass Spectroscopy (HR-LCMS). Total phenolic and flavonoid contents (TPC and TFC) were determined. In vitro, the antioxidant properties were evaluated by reducing power and antiradical activity against DPPH. Cancer cells' proliferation, apoptosis, metastatic development and angiogenesis were evaluated using Walker 256/B and MatLyLu cells. The p-coumaric acid was the major phenolic acid (1700 µg/g extract). ASE showed high levels of TPC and TFC and proved potent antioxidant effects. ASE inhibited Walker 256/B and MatLyLu cells' proliferation (Half-maximal inhibitory concentration: IC50 ≃ 150 µg/mL) and induced apoptosis. In silico and in vivo assays confirmed these findings. ASE effectively acts as a chemo-preventive compound, induces apoptosis and attenuates angiogenesis and osteolytic metastases due to Walker 256/B malignant cells.

Imatinib exhibit synergistic pleiotropy in the prevention of colorectal cancer by suppressing proinflammatory, cell survival and angiogenic signaling

Recent global incidences and mortality rates have placed colorectal cancer (CRC) at third and second positions, respectively, among both sexes of all ages. Resistance during chemotherapy is a big problem in the treatment and disease-free survival of CRC patients. Discovery of new anticancer drug(s) is a time taking process and therefore, invites studies for repurposing the known therapeutics. The present study was conceived to analyze the anticancer role of Imatinib in experimental CRC at early stages. Different experimental procedures e.g. tumor incidences or histoarchitectural changes, gene and protein expression analysis, estimations of intracellular calcium, ROS, mitochondrial membrane potential, apoptotic index and molecular docking was performed to support the hypothesis. It was observed that Imatinib could function as an immunomodulator by breaking the feed-back loop between the proinflammatory cytokines (IL-1β and TNF-α) and transcription factors (NF-κB, Jak3/Stat3) knowingly involved in increased cell proliferation during tumorigenesis via activating different intracellular signaling. Also, Imatinib could independently deregulate the other cell survival and proliferation signaling e.g. PI3-K/Akt/mTOR, Wnt/β-catenin and MAPK. Proinflammatory cytokines orchestrated intracellular signaling also involve angiogenic factors to be upregulated during CRC which were also seemed to be independently suppressed by Imatinib. Restoration of physiological apoptosis by increasing the release of intracellular calcium to generate ROS thereby reducing the mitochondrial membrane potential for the release of cytochrome c and activation of caspase-3 was also reported with Imatinib administration. Thus, it may be suggested that Imatinib show synergistic pleiotropy in suppressing the interlinked tumorigenic signaling pathways independently.

Stage-specific regulation of Gremlin1 on the differentiation and expansion of human urinary induced pluripotent stem cells into endothelial progenitors

Human urinary induced pluripotent stem cells (hUiPSCs) produced from exfoliated renal epithelial cells present in urine may provide a non-invasive source of endothelial progenitors for the treatment of ischaemic diseases. However, their differentiation efficiency is unsatisfactory and the underlying mechanism of differentiation is still unknown. Gremlin1 (GREM1) is an important gene involved in cell differentiation. Therefore, we tried to elucidate the roles of GREM1 during the differentiation and expansion of endothelial progenitors. HUiPSCs were induced into endothelial progenitors by three stages. After differentiation, GREM1 was obviously increased in hUiPSC-induced endothelial progenitors (hUiPSC-EPs). RNA interference (RNAi) was used to silence GREM1 expression in three stages, respectively. We demonstrated a stage-specific effect of GREM1 in decreasing hUiPSC-EP differentiation in the mesoderm induction stage (Stage 1), while increasing differentiation in the endothelial progenitors' induction stage (Stage 2) and expansion stage (Stage 3). Exogenous addition of GREM1 recombinant protein in the endothelial progenitors' expansion stage (Stage 3) promoted the expansion of hUiPSC-EPs although the activation of VEGFR2/Akt or VEGFR2/p42/44MAPK pathway. Our study provided a new non-invasive source for endothelial progenitors, demonstrated critical roles of GREM1 in hUiPSC-EP and afforded a novel strategy to improve stem cell-based therapy for the ischaemic diseases.

Neurotrophic Effects of Vascular Endothelial Growth Factor B and Novel Mimetic Peptides on Neurons from the Central Nervous System

Vascular endothelial growth factor B (VEGFB) is a pleiotropic trophic factor, which in contrast to the closely related VEGFA is known to have a limited effect on angiogenesis. VEGFB improves survival in various tissues including the nervous system, where the effect was observed mainly for peripheral neurons. The neurotrophic effect of VEGFB on central nervous system neurons has been less investigated. Here we demonstrated that VEGFB promotes neurite outgrowth from primary cerebellar granule, hippocampal, and retinal neurons in vitro. VEGFB protected hippocampal and retinal neurons from both oxidative stress and glutamate-induced neuronal death. The VEGF receptor 1 (VEGFR1) is required for VEGFB-induced neurotrophic and neuroprotective effects. Using a structure-based approach, we designed short peptides, termed Vefin1-7, mimicking the binding interface of VEGFB to VEGFR1. Vefins were analyzed for their secondary structure and binding to VEGF receptors and compared with previously described peptides derived from VEGFA, another ligand of VEGFR1. We show that Vefins have neurotrophic and neuroprotective effects on primary hippocampal, cerebellar granule, and retinal neurons in vitro with potencies comparable to VEGFB. Similar to VEGFB, Vefins were not mitogenic for MCF-7 cancer cells. Furthermore, one of the peptides, Vefin7, even dose-dependently inhibited the proliferation of MCF-7 cells in vitro. Unraveling the neurotrophic and neuroprotective potentials of VEGFB, the only nonangiogenic factor of the VEGF family, is promising for the development of neuroprotective peptide-based therapies.

A Qualitative Transcriptional Signature for Predicting Prognosis and Response to Bevacizumab in Metastatic Colorectal Cancer

Bevacizumab is the molecular-targeted agent used for the antiangiogenic therapy of metastatic colorectal cancer. But some patients are resistant to bevacizumab, it needs an effective biomarker to predict the prognosis and responses of metastatic colorectal cancer (mCRC) to bevacizumab therapy. In this work, we developed a qualitative transcriptional signature to individually predict the response of bevacizumab in patients with mCRC. First, using mCRC samples treated with bevacizumab, we detected differentially expressed genes between response and nonresponse groups. Then, the gene pairs, consisting of at least one differentially expressed gene, with stable relative expression orderings in the response samples but reversal stable relative expression orderings in the nonresponse samples were identified, denoted as pairs-bevacizumab. Similarly, we screened the gene pairs significantly associated with primary tumor locations, donated as pairs-LR. Among the overlapped gene pairs between the pairs-bevacizumab and pairs-LR, we adopted a feature selection process to extract gene pairs that reached the highest F-score for predicting bevacizumab response status in mCRC as the final gene pair signature (GPS), denoted as 64-GPS. In two independent datasets, the predicted response group showed significantly better overall survival than the nonresponse group (P = 6.00e-4 in GSE72970; P = 0.04 in TCGA). Genomic analyses showed that the predicted response group was characterized by frequent copy number alternations, whereas the nonresponse group was characterized by hypermutation. In conclusion, 64-GPS was an objective and robust predictive signature for patients with mCRC treated with bevacizumab, which could effectively assist in the decision of clinical therapy.

PPAR Beta/Delta and the Hallmarks of Cancer

Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor family. Three different isoforms, PPAR alpha, PPAR beta/delta and PPAR gamma have been identified. They all form heterodimers with retinoic X receptors to activate or repress downstream target genes dependent on the presence/absence of ligands and coactivators or corepressors. PPARs differ in their tissue expression profile, ligands and specific agonists and antagonists. PPARs attract attention as potential therapeutic targets for a variety of diseases. PPAR alpha and gamma agonists are in clinical use for the treatment of dyslipidemias and diabetes. For both receptors, several clinical trials as potential therapeutic targets for cancer are ongoing. In contrast, PPAR beta/delta has been suggested as a therapeutic target for metabolic syndrome. However, potential risks in the settings of cancer are less clear. A variety of studies have investigated PPAR beta/delta expression or activation/inhibition in different cancer cell models in vitro, but the relevance for cancer growth in vivo is less well documented and controversial. In this review, we summarize critically the knowledge of PPAR beta/delta functions for the different hallmarks of cancer biological capabilities, which interplay to determine cancer growth.

Targeting signaling pathways of VEGFR1 and VEGFR2 as a potential target in the treatment of breast cancer

Tumor angiogenesis allows tumor cells to grow and migrate toward the bloodstream and initiate metastasis. The interactions of vascular endothelial growth factors (VEGF) A and B, as the important regulating factors for blood vessel growth, with VEGFR1 and VEGFR2 trigger angiogenesis process. Thus, preventing these interactions led to the effective blockade of VEGF/VEGFRs signaling pathways. In this study, the inhibitory effect of a 23-mer linear peptide (VGB4), which binds to both VEGFR1 and VEGFR2, on VEGF-stimulated Human Umbilical Vein Endothelial Cells (HUVECs) and highly metastatic human breast cancer cell MDA-MB-231 proliferation was examined using MTT assay. To assess the anti-migratory potential of VGB4, HUVECs and also MDA-MB-231 cells wound healing assay was carried out at 48 and 72 h. In addition, downstream signaling pathways of VEGF associated with cell migration and invasion were investigated by quantification of mRNA and protein expression using real-time quantitative PCR and western blot in 4T1 tumor tissues and MDA-MB-231 cells. The results revealed that VGB4 significantly impeded proliferation of HUVECs and MDA-MB-231 cells, in a dose- and time-dependent manner, and migration of HUVECs and MDA-MB-231 cells for a prolonged time. We also observed statistically significant reduction of the transcripts and protein levels of focal adhesion kinase (FAK), Paxillin, matrix metalloproteinase-2 (MMP-2), RAS-related C3 botulinum substrate 1 (Rac1), P21-activated kinase-2 (PAK-2) and Cofilin-1 in VGB4-treated 4T1 tumor tissues compared to controls. The protein levels of phospho-VEGFR1, phospho-VEGFR2, Vimentin, β-catenin and Snail were markedly decreased in both VGB4-treated MDA-MB-231 cells and VGB4-treated 4T1 tumor tissues compared to controls as evidenced by western blotting. These results, in addition to our previous studies, confirm that dual blockage of VEGFR1 and VEGFR2, due to the inactivation of diverse signaling mediators, effectively suppresses tumor growth and metastasis.