Andrographolide binds to ATP-binding pocket of VEGFR2 to impede VEGFA-mediated tumor-angiogenesis

The therapeutic potential of andrographolide in cancer treatment

Cancer poses a substantial global health challenge, necessitating the widespread use of chemotherapy and radiotherapy. Despite these efforts, issues like resistance development and severe side effects remain. As such, the search for more effective alternatives is critical. Andrographolide, a naturally occurring compound, has recently gained attention for its extensive biological activities. This review explores the role of andrographolide in cancer therapy, especially focusing on the molecular mechanisms that drive its anti-tumor properties. It also examines innovative methods to enhance andrographolide's bioavailability, thus boosting its effectiveness against cancer. Notably, andrographolide has potential for use in combination with various clinical drugs, and both preclinical and clinical studies provide strong evidence supporting its broader anticancer applications. Additionally, this paper proposes future research directions for andrographolide's anti-cancer effects and discusses the challenges in its clinical usage along with current research efforts to address these issues. In summary, this review underscores andrographolide's potential roles and contributes to the development of improved cancer treatment strategies.

Synthetic Modifications of Andrographolide Targeting New Potential Anticancer Drug Candidates: A Comprehensive Overview

This review collects the synthetic modifications performed on andrographolide, a natural molecule derived from Andrographis paniculata, for oncology applications. Various pharmacomodulations were carried out, and the products were tested on different cancer cell lines. The impact of these modifications was analyzed with the aim of mapping the positions essential for activity to facilitate future research in this field. However, this study makes it clear that, in addition to structural modifications of the molecule, which can result in varying degrees of effectiveness in targeting interactions, the lipophilic capacity of the structures obtained through hemisynthesis is of significant importance.

Breast cancer stem cells generate immune-suppressive T regulatory cells by secreting TGFβ to evade immune-elimination

Cancer stem cells (CSCs), being the primary contributors in tumor initiation, metastasis, and relapse, ought to have seminal roles in evasion of immune surveillance. Tumor-promoting CD4+CD25+FOXP3+ T-regulatory cells (Tregs) have been described to abolish host defense mechanisms by impeding the activities of other immune cells including effector T cells. However, whether CSCs can convert effector T cells to immune-suppressive Treg subset, and if yes, the mechanism underlying CSC-induced Treg generation, are limitedly studied. In this regard, we observed a positive correlation between breast CSC and Treg signature markers in both in-silico and immunohistochemical analyses. Mirroring the conditions during tumor initiation, low number of CSCs could successfully generate CD4+CD25+FOXP3+ Treg cells from infiltrating CD4+ T lymphocytes in a contact-independent manner. Suppressing the proliferation potential as well as IFNγ production capacity of effector T cells, these Treg cells might be inhibiting antitumor immunity, thereby hindering immune-elimination of CSCs during tumor initiation. Furthermore, unlike non-stem cancer cells (NSCCs), CSCs escaped doxorubicin-induced apoptosis, thus constituting major surviving population after three rounds of chemotherapy. These drug-survived CSCs were also able to generate CD4+CD25+FOXP3+ Treg cells. Our search for the underlying mechanism further unveiled the role of CSC-shed immune-suppressive cytokine TGFβ, which was further increased by chemotherapy, in generating tumor Treg cells. In conclusion, during initiation as well as after chemotherapy, when NSCCs are not present in the tumor microenvironment, CSCs, albeit present in low numbers, generate immunosuppressive CD4+CD25+FOXP3+ Treg cells in a contact-independent manner by shedding high levels of immune-suppressive Treg-polarizing cytokine TGFβ, thus escaping immune-elimination and initiating the tumor or causing tumor relapse.

Exploring the potential of Andrographis paniculata for developing novel HDAC inhibitors: an in silico approach

Cancer is one of the dreaded diseases of the twentieth century, emerging the major global causes of human morbidity. Cancer research in the last 15 years has provided unprecedented information on the role of epigenetics in cancer initiation and progression. Histone deacetylases (HDACs) are recognized as important epigenetic markers in cancer, whose overexpression leads to increased metastasis and angiogenesis. In the current study, thirty-four (34) compounds from Andrographis paniculata were screened for the identification of potential candidate drugs, targeting three Class I HDACs (Histone deacetylases), namely HDAC1 (PDB id 5ICN), HDAC3 (PDB id 4A69) and HDAC8 (PDB id 5FCW) through computer-assisted drug discovery study. Results showed that some of the phytochemicals chosen for this study exhibited significant drug-like properties. In silico molecular docking study further revealed that out of 34 compounds, the flavonoid Andrographidine E had the highest binding affinities towards HDAC1 (-9.261 Kcal mol-1) and 3 (-9.554 Kcal mol-1) when compared with the control drug Givinostat (-8.789 and -9.448 Kcal mol-1). The diterpenoid Andrographiside displayed the highest binding affinity (-9.588 Kcal mol-1) to HDAC8 compared to Givinostat (-8.947 Kcal mol-1). Statistical analysis using Principal Component Analysis tool revealed that all 34 phytocompounds could be clustered in four statistical groups. Most of them showed high or comparable inhibitory potentials towards HDAC target protein. Finally, the stability of top-ranked complexes (Andrographidine E-HDAC1 and HDAC3; Andrographiside-HDAC8) at the physiological condition was validated by Molecular Dynamic Simulation and MM-PBSA study.Communicated by Ramaswamy H. Sarma.

Effect of sunitinib against Echinococcus multilocularis through inhibition of VEGFA-induced angiogenesis

BACKGROUND

Alveolar echinococcosis (AE) is a lethal zoonosis caused by the fox tapeworm Echinococcus multilocularis. The disease is difficult to treat, and an effective therapeutic drug is urgently needed. Echinococcus multilocularis-associated angiogenesis is required by the parasite for growth and metastasis; however, whether antiangiogenic therapy is effective for treating AE is unclear.

METHODS

The in vivo efficacy of sunitinib malate (SU11248) was evaluated in mice by secondary infection with E. multilocularis. Enzyme-linked immunosorbent assays (ELISAs) were used to evaluate treatment effects on serum IL-4 and vascular endothelial growth factor A (VEGFA) levels after SU11248 treatment. Gross morphological observations and immunohistochemical staining were used to evaluate the impact of SU11248 on angiogenesis and the expression of pro-angiogenic factors VEGFA and VEGF receptor 2 (VEGFR2) in the metacestode tissues. Furthermore, the anthelmintic effects of SU11248 were tested on E. multilocularis metacestodes in vitro. The effect of SU11248 on the expression of VEGFA, VEGFR2, and phosphorylated VEGFR2 (p-VEGFR2) in liver cells infected with protoscoleces in vitro was detected by western blotting, reverse transcription quantitative polymerase chain reaction (RT-qPCR), and enzyme-linked immunosorbent assay (ELISA). The influence of SU11248 on endothelial progenitor cell (EPC) proliferation and migration was determined using CCK8 and transwell assays.

RESULTS

In vivo, SU11248 treatment markedly reduced neovascular lesion formation and substantially inhibited E. multilocularis metacestode growth in mice. Further, it exhibited high anti-hydatid activity as efficiently as albendazole (ABZ), and the treatment resulted in reduced protoscolex development. In addition, VEGFA, VEGFR2, and p-VEGFR2 expression was significantly decreased in the metacestode tissues after SU11248 treatment. However, no effect of SU11248 on serum IL-4 levels was observed. In vitro, SU11248 exhibited some anthelmintic effects and damaged the cellular structure in the germinal layer of metacestodes at concentrations below those generally considered acceptable for treatment (0.12-0.5 μM). Western blotting, RT-qPCR, and ELISA showed that in co-cultured systems, only p-VEGFR2 levels tended to decrease with increasing SU11248 concentrations. Furthermore, SU11248 was less toxic to Reuber rat hepatoma (RH) cells and metacestodes than to EPCs, and 0.1 μM SU11248 completely inhibited EPC migration to the supernatants of liver cell and protoscolex co-cultures.

CONCLUSIONS

SU11248 is a potential candidate drug for the treatment of AE, which predominantly inhibits parasite-induced angiogenesis. Host-targeted anti-angiogenesis treatment strategies constitute a new avenue for the treatment of AE.

Anti-Cancer Agent: The Labdane Diterpenoid-Andrographolide

In spite of the progress in treatment strategies, cancer remains a major cause of death worldwide. Therefore, the main challenge should be the early diagnosis of cancer and the design of an optimal therapeutic strategy to increase the patient's life expectancy as well as the continuation of the search for increasingly active and selective molecules for the treatment of different forms of cancer. In the recent decades, research in the field of natural compounds has increasingly shifted towards advanced and molecular level understandings, thus leading to the development of potent anti-cancer agents. Among them is the diterpene lactone andrographolide, isolated from Andrographis paniculata (Burm.f.) Wall. ex Nees that showed shows a plethora of biological activities, including not only anti-cancer activity, but also anti-inflammatory, anti-viral, anti-bacterial, neuroprotective, hepatoprotective, hypoglycemic, and immunomodulatory properties. Andrographolide has been shown to act as an anti-tumor drug by affecting specific molecular targets that play a part in the development and progression of several cancer types including breast, lung, colon, renal, and cervical cancer, as well as leukemia and hepatocarcinoma. This review comprehensively and systematically summarized the current research on the potential anti-cancer properties of andrographolide highlighting its mechanisms of action, pharmacokinetics, and potential side effects and discussing the future perspectives, challenges, and limitations of use.

The use of machine learning modeling, virtual screening, molecular docking, and molecular dynamics simulations to identify potential VEGFR2 kinase inhibitors

Targeting the signaling pathway of the Vascular endothelial growth factor receptor-2 is a promising approach that has drawn attention in the quest to develop novel anti-cancer drugs and cardiovascular disease treatments. We construct a screening pipeline using machine learning classification integrated with similarity checks of approved drugs to find new inhibitors. The statistical metrics reveal that the random forest approach has slightly better performance. By further similarity screening against several approved drugs, two candidates are selected. Analysis of absorption, distribution, metabolism, excretion, and toxicity, along with molecular docking and dynamics are performed for the two candidates with regorafenib as a reference. The binding energies of molecule1, molecule2, and regorafenib are - 89.1, - 95.3, and - 87.4 (kJ/mol), respectively which suggest candidate compounds have strong binding to the target. Meanwhile, the median lethal dose and maximum tolerated dose for regorafenib, molecule1, and molecule2 are predicted to be 800, 1600, and 393 mg/kg, and 0.257, 0.527, and 0.428 log mg/kg/day, respectively. Also, the inhibitory activity of these compounds is predicted to be 7.23 and 7.31, which is comparable with the activity of pazopanib and sorafenib drugs. In light of these findings, the two compounds could be further investigated as potential candidates for anti-angiogenesis therapy.

Apoptotic and Cell Cycle Effects of Triterpenes Isolated from Phoradendron wattii on Leukemia Cell Lines

Current antineoplastic agents present multiple disadvantages, driving an ongoing search for new and better compounds. Four lupane-type triterpenes, 3α,24-dihydroxylup-20(29)-en-28-oic acid (1), 3α,23-dihydroxy-30-oxo-lup-20(29)-en-28-oic acid (2), 3α,23-O-isopropylidenyl-3α,23-dihydroxylup-20(29)-en-28-oic acid (3), and 3α,23-dihydroxylup-20(29)-en-28-oic acid (4), previously isolated from Phoradendron wattii, were evaluated on two cell lines of chronic (K562) and acute (HL60) myeloid leukemia. Compounds 1, 2, and 4 decreased cell viability and inhibit proliferation, mainly in K562, and exhibited an apoptotic effect from 24 h of treatment. Of particular interest is compound 2, which caused arrest in active phases (G2/M) of the cell cycle, as shown by in silico study of the CDK1/Cyclin B/Csk2 complex by molecular docking. This compound [3α,23-dihydroxy-30-oxo-lup-20(29)-en-28-oic acid] s a promising candidate for incorporation into cancer treatments and deserves further study.

FOXP3/HAT1 Axis Controls Treg Infiltration in the Tumor Microenvironment by Inducing CCR4 Expression in Breast Cancer

Infiltrating T-regulatory cells in the tumor microenvironment is a key impediment to immunotherapy and is linked to a poor prognosis. We found that tumor-infiltrating Tregs express a higher expression of the chemokine receptor CCR4 than peripheral Tregs in breast cancer patients. CCL22 and CCL17 are released by tumor cells and tumor-associated macrophages, attracting CCR4+ Tregs to the tumor site. The Treg lineage-specific transcription factor FOXP3 changes the CCR4 promoter epigenetically in conjunction with HAT1 to provide a space for FOXP3 binding and activation of the CCR4 gene. To increase CCR4 expression in Tregs, the FOXP3/HAT1 axis is required for permissive (K23 and K27) or repressive (K14 and K18) acetylation of histone-3. In murine breast and melanoma tumor models, genetic ablation of FOXP3 reduced CCR4+ Treg infiltration and tumor size while also restoring anti-tumor immunity. Overexpression of FOXP3, on the other hand, increased CCR4+ Treg infiltration, resulting in a decreased anti-tumor immune response and tumor progression. These findings point to FOXP3 playing a new role in the tumor microenvironment as a transcriptional activator of CCR4 and a regulator of Treg infiltration.

Andrographolide Promotes Interaction Between Endothelin-Dependent EDNRA/EDNRB and Myocardin-SRF to Regulate Pathological Vascular Remodeling

Introduction

Pathological vascular remodeling is a hallmark of various vascular diseases. Smooth muscle cell (SMC) phenotypic switching plays a pivotal role during pathological vascular remodeling. The mechanism of how to regulate SMC phenotypic switching still needs to be defined. This study aims to investigate the effect of Andrographolide, a key principle isolated from Andrographis paniculate, on pathological vascular remodeling and its underlying mechanism.

Methods

A C57/BL6 mouse left carotid artery complete ligation model and rat SMCs were used to determine whether Andrographolide is critical in regulating SMC phenotypic switching. Quantitative real-time PCR, a CCK8 cell proliferation assay, BRDU incorporation assay, Boyden chamber migration assay, and spheroid sprouting assay were performed to evaluate whether Andrographolide suppresses SMC proliferation and migration. Immunohistochemistry staining, immunofluorescence staining, and protein co-immunoprecipitation were used to observe the interaction between EDNRA, EDNRB, and Myocardin-SRF.

Results

Andrographolide inhibits neointimal hyperplasia in the left carotid artery complete ligation model. Andrographolide regulates SMC phenotypic switching characterized by suppressing proliferation and migration. Andrographolide activates the endothelin signaling pathway exhibited by dramatically inducing EDNRA and EDNRB expression. The interaction between EDNRA/EDNRB and Myocardin-SRF resulted in promoting SMC differentiation marker gene expression.

Conclusion

Andrographolide plays a critical role in regulating pathological vascular remodeling.

Andrographolide: A review of its pharmacology, pharmacokinetics, toxicity and clinical trials and pharmaceutical researches

Andrographis paniculata (Burm. f.) Wall. ex Nees, a renowned herb medicine in China, is broadly utilized in traditional Chinese medicine (TCM) for the treatment of cold and fever, sore throat, sore tongue, snake bite with its excellent functions of clearing heat and toxin, cooling blood and detumescence from times immemorial. Modern pharmacological research corroborates that andrographolide, the major ingredient in this traditional herb, is the fundamental material basis for its efficacy. As the main component of Andrographis paniculata (Burm. f.) Wall. ex Nees, andrographolide reveals numerous therapeutic actions, such as antiinflammatory, antioxidant, anticancer, antimicrobial, antihyperglycemic and so on. However, there are scarcely systematic summaries on the specific mechanism of disease treatment and pharmacokinetics. Moreover, it is also found that it possesses easily ignored security issues in clinical application, such as nephrotoxicity and reproductive toxicity. Thereby it should be kept a lookout over in clinical. Besides, the relationship between the efficacy and security issues of andrographolide should be investigated and evaluated scientifically. In this review, special emphasis is given to andrographolide, a multifunctional natural terpenoids, including its pharmacology, pharmacokinetics, toxicity and pharmaceutical researches. A brief overview of its clinical trials is also presented. This review intends to systematically and comprehensively summarize the current researches of andrographolide, which is of great significance for the development of andrographolide clinical products. Noteworthy, those un-cracked issues such as specific pharmacological mechanisms, security issues, as well as the bottleneck in clinical transformation, which detailed exploration and excavation are still not to be ignored before achieving integration into clinical practice. In addition, given that current extensive clinical data do not have sufficient rigor and documented details, more high-quality investigations in this field are needed to validate the efficacy and/or safety of many herbal products.

Single-cell transcriptional profiling reveals the heterogeneity in embryonal rhabdomyosarcoma

ABSTRACT

Rhabdomyosarcoma is the most common soft tissue sarcoma in children, and embryonal rhabdomyosarcoma is the most typical type of rhabdomyosarcoma. The heterogeneity, etiology, and origin of embryonal rhabdomyosarcoma remain unknown.After obtaining the gene expression data of every cell in the tumor tissue by single-cell RNA sequencing, we used the Seurat package in R studio for quality control, analysis, and exploration of the data. All cells are divided into tumor cells and non-tumor cells, and we chose tumor cells by marker genes. Then, we repeated the process to cluster the tumor cells and divided the subgroups by their differentially expressed genes and gene ontology/Kyoto Encyclopedia of Genes and Genomes analysis. Additionally, Monocle 2 was used for pseudo-time analysis to obtain the evolution trajectory of cells in tumor tissues.Tumor cells were divided into 5 subgroups according to their functions, which were characterized by high proliferation, sensing and adaptation to oxygen availability, enhanced epigenetic modification, enhanced nucleoside phosphonic acid metabolism, and ossification. Evolution trajectory of cells in tumor tissues is obtained.We used pseudo-time analysis to distinguish between mesenchymal stem cells and fibroblasts, proved that embryonal rhabdomyosarcoma in the pelvic originated from skeletal muscle progenitor cells, showed the evolutionary trajectory of embryonal rhabdomyosarcoma, and improved the method of evaluating the degree of malignancy of embryonal rhabdomyosarcoma.

Andrographolide and its derivatives: Current achievements and future perspectives

Natural product andrographolide isolated from the plant Andrographis paniculata shows a plethora of biological activities, including anti-tumor, anti-bacterial, anti-inflammation, anti-virus, anti-fibrosis, anti-obesity, immunomodulatory and hypoglycemic activities. Based on extensive chemical structural modifications, a series of andrographolide derivatives with improved bioavailability and druggability has been developed. Moreover, greater understanding of their mechanisms of action at the molecular and cellular level has been thoroughly investigated. In this review, we give an outlook for the therapeutical potential of andrographolide and its derivatives in diverse diseases and highlighted the drug design, pharmacokinetic and mechanistic studies for the past ten years, together with a brief overview of the pharmacological effects. Notably, we focused to provide a critical enlightenment of the area of andrographolide and its derivatives with the intent of indicating the future perspectives, challenges and limitations. We believe that this review paper will benefit drug discovery where andrographolide was used as a template, shed light on the identification of drug targets for andrographolide and its analogs, as well as increase our knowledge for using them for therapeutic application, including the treatment for various forms of cancers.

Transcriptional regulation of VEGFA expression in T-regulatory cells from breast cancer patients

The initiation of new blood vessel formation (neo-angiogenesis) is one of the primary requirements for the establishment of tumor. As the tumor grows beyond a certain size, a hypoxic-condition arises in the inner core of tumor, triggering the release of chemokines, which attract T-regulatory (Treg) cells in the tumor-site. The presence of FOXP3, a lineage-specific transcription factor, expressing Treg cells in various types of tumor implements immunosuppressive and tumor-promoting strategies. One such strategy is the invitation of endothelial cells for neo-vascularization in the tumor site. Here we report that as the disease progresses, Treg cells from breast cancer patients are capable of secreting high-amount of VEGFA. The VEGFA promoter lacks Treg-specific transcription factor FOXP3 binding site. FOXP3 in association with locus-specific transcription factor STAT3 binds to VEGFA promoter to induce its transcription in Treg cells obtained from breast cancer patients. Treg cell-secreted VEGFA induces neo-angiogenesis from endothelial cells under in-vitro conditions. Targeting Tregs in mice with breast tumor reduces tumor growth as well as the level of neo-angiogenesis in the tumor tissue.

Current Trends on Repurposing and Pharmacological Enhancement of Andrographolide

Andrographolide, the main bioactive component separated from Andrographis paniculata in 1951, has been scrutinized with a modern drug discovery approach for anti-inflammatory properties since 1984. Identification of new uses of existing drugs can be facilitated by searching for evidence linking them to known or yet undiscovered drug targets and human disease states to develop new therapeutic indications.Furthermore, a wide spectrum of biological properties of andrographolide such as anticancer, antibacterial, antiviral, hepatoprotective, antioxidant, anti-malarial, anti-atherosclerosis are also reported. However, poor water solubility and instability limit its clinical application. It becomes crucial to enhance its pharmacological function and find a new treatment option for more diseases. Therefore, this article reviews the major recent developments in andrographolide, including repurposing applications in different diseases and underlying mechanisms, particularly focusing on pharmacological enhancement of andrographolide such as derivatives, chemical modifications with potent biological activity and drug delivery. The repurposing and pharmacological enhancement of andrographolide would not only have exciting therapeutic potential to different diseases to facilitate drug marketing, but also decrease the economic burden on healthcare worldwide.

Synergistic potential of dual andrographolide and melatonin targeting of metastatic colon cancer cells: Using the Chou-Talalay combination index method

Colorectal cancer (CRC) mortality has diminished for decades due to new and improved treatment profiles. However, CRC still ranks as the third most diagnosed cancer in the US. Therefore, a new therapeutic approach is needed to overcome colospheroids inhibition and drug resistance. It is well documented that andrographolide (AGP) and melatonin (MLT) have anti-carcinogenic properties. Our goal was to evaluate their synergistic effects on metastatic colon cancer cells (mCRC) and colospheroids. HT-29 and HCT-15 mCRC cells were simultaneously treated with serial dilutions of AGP and MLT for 24, 48 and 72 h. Cell viability was monitored using the MTT assay. The Chou-Talalay method for drug combination is based on the median effect equation, providing a theoretical basis for the combination index and the isobologram equation. This allows quantitative determination of drug interactions using the CompuSyn software, where CI < 1, = 1, and >1 indicates synergistic, additive, and antagonistic effects respectively. Our results demonstrate that AGP and MLT in combination show synergism with CI values of 0.35293 and 0.34152 for HT-29 and HCT-15 respectively and a fractional inhibition of Fa = 0.50-0.90, as shown by the Fa-CI plot and isobologram. The synergism value was validated in colospheroids (HT-29-s and HCT-15-s) based on morphology, viability, and colony formation and in 5-FU drug resistant cell (HT-29R and HCT-116R) viability. The mechanism(s) of decreased cell viability are due to the induction of ER stress proteins and angiogenic inhibition. Our results provide rationale for using AGP in combination with MLT on mCRC.

Diarylureas as Antitumor Agents

The diarylurea is a scaffold of great importance in medicinal chemistry as it is present in numerous heterocyclic compounds with antithrombotic, antimalarial, antibacterial, and anti-inflammatory properties. Some diarylureas, serine-threonine kinase or tyrosine kinase inhibitors, were recently reported in literature. The first to come into the market as an anticancer agent was sorafenib, followed by some others. In this review, we survey progress over the past 10 years in the development of new diarylureas as anticancer agents.

Inhibiting the NLRP3 inflammasome with MCC950 ameliorates retinal neovascularization and leakage by reversing the IL-1β/IL-18 activation pattern in an oxygen-induced ischemic retinopathy mouse model

Activation of the nucleotide-binding domain leucine-rich repeat and pyrin domain containing receptor 3 (NLRP3) inflammasome plays an important role in ocular neovascularization. In our study, we found that the expression and activation levels of NLRP3 inflammasome components, including NLRP3, an apoptosis-associated speck-like protein (ASC) containing caspase activation and recruitment domain (CARD) and caspase-1 (CAS1), were significantly upregulated. In addition, we found interleukin (IL)-1β activity increased while IL-18 activity decreased in the retinas of oxygen-induced ischemic retinopathy (OIR) mice. MCC950, an inhibitor of NLRP3, reversed the IL-1β/IL-18 activation pattern, inhibited the formation of retinal neovascularization (RNV), decreased the number of acellular capillaries and reduced leakage of retinal vessels. Moreover, MCC950 could regulate the expression of endothelial cell- and pericyte function-associated molecules, such as vascular endothelial growth factor (VEGF), VEGF receptor (VEGFR)1, VEGFR2, matrix metalloproteinase (MMP)2, MMP9, tissue inhibitor of metalloproteinases (TIMP)1, TIMP2, platelet-derived growth factor receptor-β (PDGFR-β), platelet-derived growth factor-B (PDGF-B), and angiopoietin2 (Ang2). In vitro, recombinant human (r)IL-18 and rIL-1β regulated the expression of endothelial cell- and pericyte function-associated molecules and the proliferation and migration of endothelial cells and pericytes. We therefore determined that inhibiting the NLRP3 inflammasome with MCC950 can regulate the function of endothelial cells and pericytes by reversing the IL-1β/IL-18 activation pattern to ameliorate RNV and leakage; thereby opening new avenues to treat RNV-associated ocular diseases.

Long Non-coding RNA IRAIN Inhibits VEGFA Expression via Enhancing Its DNA Methylation Leading to Tumor Suppression in Renal Carcinoma

Aims: Long non-coding RNA IRAIN (lncRNA IRAIN) plays a critical role in numerous malignancies. However, the function of lncRNA IRAIN in renal carcinoma (RC) remains enigmatic. The purpose of this study is to characterize the effects of lncRNA IRAIN on RC progression.

Methods: The expression pattern of lncRNA IRAIN and the vascular endothelial growth factor A (VEGFA) in RC tissues and cells was characterized by RT-qPCR and Western blot analysis. The roles of lncRNA IRAIN and VEGFA in the progression of RC were studied by gain- or loss-of-function experiments. Bioinformatics data analysis was used to predict CpG islands in the VEGFA promoter region. MSP was applied to detect the level of DNA methylation in RC cells. The interaction between lncRNA IRAIN and VEGFA was identified by RNA immunoprecipitation and RNA-protein pull down assays. Recruitment of DNA methyltransferases (Dnmt) to the VEGFA promoter region was achieved by chromatin immunoprecipitation. The subcellular localization of lncRNA IRAIN was detected by fractionation of nuclear and cytoplasmic RNA. Cell viability was investigated by CCK-8 assay, cell migration was tested by transwell migration assay, and apoptosis was analyzed by flow cytometry. The expression of epithelial–mesenchymal transition-related and apoptotic factors was evaluated by Western blot analysis. Finally, the effect of the lncRNA IRAIN/VEGFA axis was confirmed in an in vivo tumor xenograft model.

Results: LncRNA IRAIN was poorly expressed in RC tissues and cells with a primary localization in the nucleus, while VEGFA was highly expressed. Overexpression of lncRNA IRAIN or knockdown of VEGFA inhibited cell proliferation and migration and induced the apoptosis of RC cells. Bioinformatics analysis indicated the presence of CpG islands in the VEGFA promoter region. Lack of methylation at specific sites in the VEGFA promoter region was detected through MSP assay. We found that lncRNA IRAIN was able to inhibit VEGFA expression through recruitment of Dnmt1, Dnmt3a, and Dnmt3b to the VEGFA promoter region. LncRNA IRAIN was also able to suppress RC tumor growth via repression of VEGFA in an in vivo mouse xenograft model.

Conclusion: Our data shows that by downregulating VEGFA expression in RC, the lncRNA IRAIN has tumor-suppressive potential.

Quinoline-Based Molecules Targeting c-Met, EGF, and VEGF Receptors and the Proteins Involved in Related Carcinogenic Pathways

The quinoline ring system has long been known as a versatile nucleus in the design and synthesis of biologically active compounds. Currently, more than one hundred quinoline compounds have been approved in therapy as antimicrobial, local anaesthetic, antipsychotic, and anticancer drugs. In drug discovery, indeed, over the last few years, an increase in the publication of papers and patents about quinoline derivatives possessing antiproliferative properties has been observed. This trend can be justified by the versatility and accessibility of the quinoline scaffold, from which new derivatives can be easily designed and synthesized. Within the numerous quinoline small molecules developed as antiproliferative drugs, this review is focused on compounds effective on c-Met, VEGF (vascular endothelial growth factor), and EGF (epidermal growth factor) receptors, pivotal targets for the activation of important carcinogenic pathways (Ras/Raf/MEK and PI3K/AkT/mTOR). These signalling cascades are closely connected and regulate the survival processes in the cell, such as proliferation, apoptosis, differentiation, and angiogenesis. The antiproliferative biological data of remarkable quinoline compounds have been analysed, confirming the pivotal importance of this ring system in the efficacy of several approved drugs. Furthermore, in view of an SAR (structure-activity relationship) study, the most recurrent ligand–protein interactions of the reviewed molecules are summarized.

The Prowess of Andrographolide as a Natural Weapon in the War against Cancer

There has been a paradigm shift in our understanding about the multifaceted nature of cancer, and a wealth of information has revealed that single-target drugs are not good enough to provide satisfactory clinical outcomes and therapeutic effects for complex diseases which involve multiple factors. Therefore, there has been a reignition to search for natural products having premium pharmacological activities aim to efficiently target multiple deregulated cellular signaling pathways. Andrographolide, a diterpene lactone from Andrographis paniculata was brought into to the limelight because of its ability to inhibit cancer cell proliferation and induce apoptosis. Here we reviewed andrographolide on cellular pathways regulation including Wnt/β-catenin, mTOR, VEGF-mediated intracellular signaling, as well as TRAIL-mediated apoptosis to inhibit cancer development.

The role and mechanism of asymmetric dimethylarginine in fetal growth restriction via interference with endothelial function and angiogenesis

PURPOSE

Fetal growth restriction (FGR) is a high-risk pregnancy, and placental dysfunction is the main cause of FGR. The upregulation of asymmetric dimethylarginine (ADMA) is linked to FGR pathology, but the mechanism needs to be investigated.

METHODS

The levels of ADMA and other related molecules were measured in human biological samples. We further used human umbilical vein endothelial cells (HUVECs) to reveal the mechanism of ADMA-induced FGR in vitro.

RESULTS

Compared with the control group, FGR patients had higher placental resistance, and ADMA levels were increased in the maternal blood, cord blood, and placenta; additionally, nitric oxide (NO) production decreased, accompanied by a decreased expression of endogenous NO synthase (eNOS). The expression of vascular growth factor (VEGF) and placental growth factor (PLGF) in the maternal blood during the third trimester and umbilical cord of the FGR group was lower than the control group. The PLGF levels in the placentas of the FGR group were also reduced, while the expression of soluble fms-like tyrosine kinase-1 (sFlt-1) increased. In in vitro cell experiments, NO production was obviously lower when the cells were exposed to 100 μM of ADMA, with no difference in eNOS expression. There was a dose-dependent decrease in PLGF expression with increasing doses of ADMA, and the levels of sFlt-1 increased. Moreover, we confirmed that tube formation in HUVECs was lower after ADMA treatment compared with the control group.

CONCLUSION

The accumulation of ADMA during pregnancy has an adverse effect on fetal development via interference with placental endothelial function and angiogenesis.

AGS-30, an andrographolide derivative, suppresses tumor angiogenesis and growth in vitro and in vivo

Poor bioavailability and limited efficacy are challenges associated with using andrographolide as a therapeutic agent. We recently synthesized AGS-30, a new andrographolide derivative, in our laboratory. In this study we investigated the potential anti-tumor effect of AGS-30 and the underlying mechanisms, particularly those related to angiogenesis. Results from our in vitro experiments showed that AGS-30 exerted anti-angiogenic effects by inhibiting endothelial cell proliferation, migration, invasion, and tube formation. Phosphorylation and activation of angiogenesis-related signaling molecules (e.g., vascular endothelial growth factor [VEGF] receptor 2, mitogen-activated protein kinase kinase 1/2, extracellular signal-regulated kinase 1/2, mechanistic target of rapamycin [mTOR], protein kinase B [Akt], and p38) were markedly reduced by AGS-30. Meanwhile, AGS-30 potently inhibited cell proliferation and phosphorylation of cell survival-related proteins (e.g., Akt, mTOR, and ERK1/2) and decreased the expression of VEGF in HT-29 colon cancer cells. AGS-30 blocked microvessel sprouting in a rat aortic ring model and blood vessel formation in zebrafish embryos and a mouse Matrigel plug model. Additionally, AGS-30 suppressed tumor growth and angiogenesis in HT-29 colon cancer cell xenografts in nude mice. These effects were not observed when same concentration of andrographolide, the parent compound of AGS-30, was used. Thus, AGS-30 exerted a strong antitumor effect by inhibiting tumor cell growth and angiogenesis and is a candidate compound for the treatment of cancer.