Norcantharidin inhibits tumor angiogenesis via blocking VEGFR2/MEK/ERK signaling pathways

Nanoemulsion based lipid nanoparticles for effective demethylcantharidin delivery to cure liver cancer

Demethylcantharidin (DEM) is a widely used antitumor drug; however, its poor tumor targeting and serious organotoxicity limit its application. The aim of this study was to develop a new drug delivery system for efficient delivery of DEM. Nanoemulsion based lipid nanoparticles containing demethylcantharidin (DNLNs) were prepared by loading nanoemulsions into lipid nanoparticles. The cells proliferation, apoptosis, cycle, and uptake were investigated by Cell counting kit-8 (CCK-8), flow cytometry, and in situ fluorescence assays, respectively. Then, we established the H22 tumor-bearing mouse model to evaluate the antitumor efficacy of DNLNs and further studied its organ toxicity and distribution. DNLNs significantly inhibited the proliferation and promoted apoptosis of H22 cells, and H22 cells could take up more DNLNs. Compared with DEM, DNLNs had certain tumor-targeting properties, and the tumor inhibition rate increased by 23.24%. Moreover, DNLNs can increase white blood cell count and reduce organ toxicity. This study paves the way for nanoemulsion-based lipid nanoparticle (NLNs)-efficient DEM delivery to treat liver cancer.

Eriocitrin Inhibits Angiogenesis by Targeting VEGFR2-Mediated PI3K/AKT/mTOR Signaling Pathways

Eriocitrin, a flavanone found in peppermint and citrus fruits, is known to possess many physiological activities. However, the anti-angiogenic effects of eriocitrin are yet to be fully elucidated. Therefore, the objective of this research was to explore the anti-angiogenic effects of eriocitrin both in vitro and in vivo as well as its underlying mechanism. Anti-angiogenic effects of eriocitrin were evaluated utilizing in vitro models of angiogenesis, including inhibition of tube formation, and induction of apoptosis in human umbilical vein endothelial cells (HUVECs). A chorioallantoic membrane (CAM) assay in chick embryos was also performed to evaluate the in vivo effects of eriocitrin on angiogenesis. Results showed significant eriocitrin effects on proliferation, tube formation, migration, and apoptosis in HUVECs. Furthermore, in vivo analysis revealed that eriocitrin significantly suppressed the formation of new blood vessels. In particular, it regulated MAPK/ERK signaling pathway and VEGFR2, inhibited the downstream PI3K/AKT/mTOR signaling pathway, and activated apoptosis signals such as caspase cascades. In HUVECs, the expression of matrix metalloproteinases (MMP-2 and MMP-9) exhibited an inhibitory effect on angiogenesis through the suppression of the signaling pathway. Therefore, eriocitrin presents potential for development into an antiangiogenic therapeutic agent.

Tongluo Shenggu capsule promotes angiogenesis to ameliorate glucocorticoid-induced femoral head necrosis via upregulating VEGF signaling pathway

BACKGROUND

Tongluo Shenggu Capsule (TLSGC) is a product of Traditional Chinese patent medicine that has been effective in glucocorticoid-induced osteonecrosis of the femoral head (GIONFH) clinically for many years. It is made from water extracts of a well-used herbal and dietary supplement-pigeon pea leaves. Nevertheless, the material basis and pharmacological mechanisms of TLSGC ameliorating GIONFH needed to be better defined.

PURPOSE

To investigate the material basis and pharmacological mechanisms of TLSGC to ameliorate GIONFH.

METHODS

The chemical compositions in TLSGC were characterized using the LC-MS system. Based on integrating the relevant targets of TLSGC in MedChem Studio software and GIONFH-related genes in our previous work, a "drug targets-disease genes" interaction network was constructed. The candidate targets of TLSGC ameliorating GIONFH were filtrated by topological characteristic parameters and further experimental validated based on methylprednisolone-induced rat model and dexamethasone-inhibited human umbilical vein endothelial cells (HUVECs).

RESULTS

A total of 33 chemical compositions were characterized in TLSGC. Based on these compositions and GIONFH-related genes, 122 hub genes were selected according to topological parameters calculation. Biological functions were mainly enriched in four over-expressed modules of vascular damage, inflammation and apoptosis, bone metabolism and energy metabolism. The hub genes had the maximum enrichment degree in the VEGF-VEGFR2-PKC-Raf1-MEK-ERK signaling axis of the VEGF pathway. Experimentally, the therapeutic effects of TLSGC against GIONFH in rats were proved by micro-CT and pathological examination. Then, the protective effects of TLSGC on vascular damage were determined using angiography, CD31 immunohistochemistry, vascular function indicators in vivo, aortic ring test ex vivo, and the HUVECs activities in vitro including migration, invasion and tube formation. Mechanically, TLSGC effectively suppressed the downregulation of VEGF and VEGFR2 and their downstream targets, including Raf-1, PKC, p-MEK, and p-ERK proteins both in vivo and in vitro.

CONCLUSION

TLSGC could promote angiogenesis by upregulating the VEGF-VEGFR2-PKC-Raf-1-MEK-ERK signaling axis, thereby exerting an apparent curative effect on GIONFH.

Review targeted drug delivery systems for norcantharidin in cancer therapy

Norcantharidin (NCTD) is a demethylated derivative of cantharidin (CTD), the main anticancer active ingredient isolated from traditional Chinese medicine Mylabris. NCTD has been approved by the State Food and Drug Administration for the treatment of various solid tumors, especially liver cancer. Although NCTD greatly reduces the toxicity of CTD, there is still a certain degree of urinary toxicity and organ toxicity, and the poor solubility, short half-life, fast metabolism, as well as high venous irritation and weak tumor targeting ability limit its widespread application in the clinic. To reduce its toxicity and improve its efficacy, design of targeted drug delivery systems based on biomaterials and nanomaterials is one of the most feasible strategies. Therefore, this review focused on the studies of targeted drug delivery systems combined with NCTD in recent years, including passive and active targeted drug delivery systems, and physicochemical targeted drug delivery systems for improving drug bioavailability and enhancing its efficacy, as well as increasing drug targeting ability and reducing its adverse effects.

Graphical Abstract

Inhibition and potential treatment of colorectal cancer by natural compounds via various signaling pathways

Colorectal cancer (CRC) is a common type of malignant digestive tract tumor with a high incidence rate worldwide. Currently, the clinical treatment of CRC predominantly include surgical resection, postoperative chemotherapy, and radiotherapy. However, these treatments contain severe limitations such as drug side effects, the risk of recurrence and drug resistance. Some natural compounds found in plants, fungi, marine animals, and bacteria have been shown to inhibit the occurrence and development of CRC. Although the explicit molecular mechanisms underlying the therapeutic effects of these compounds on CRC are not clear, classical signaling transduction pathways such as NF-kB and Wnt/β-catenin are extensively regulated. In this review, we have summarized the specific mechanisms regulating the inhibition and development of CRC by various types of natural compounds through nine signaling pathways, and explored the potential therapeutic values of these natural compounds in the clinical treatment of CRC.

Preclinical evaluations of Norcantharidin liposome and emulsion hybrid delivery system with improved encapsulation efficiency and enhanced antitumor activity

BACKGROUND

Norcantharidin (NCTD) has a certain degree of hydrophilicity and poor lipophilicity, and has some side-effects, including short t_1/2, vascular irritation, cardiotoxicity and nephrotoxicity, which bring difficulties for formulation research. In this study, we aim to develop a novel nanocarrier to improve encapsulation efficiency, increase sterilization stability and enhance antitumor activity.

METHODS

Phospholipid complexes methods were used for increasing the lipophilicity of norcantharidin (NCTD), then NCTD phospholipid complexes were not only loaded in the oil phase and oil-water interface surface, but also encapsulated in phospholipid bilayers to obtain NCTD liposome-emulsion hybrid (NLEH) delivery system. The in vitro cytotoxicity and apoptosis, in vivo tissue distribution, tumor penetration, heterotopic and orthotopic antitumor studies were conducted to evaluate therapeutic effect.

RESULTS

NLEH exhibited an improved encapsulation efficiency (89.3%) and a better sterilization stability, compared to NCTD liposomes and NCTD emulsions. NLEH can achieve a better antitumor activity by promoting absorption (1.93-fold), prolonging blood circulation (2.08-fold), enhancing tumor-targeting accumulation (1.19 times), improving tumor penetration, and increasing antitumor immunity.

CONCLUSIONS

The liposome-emulsion hybrid (LEH) delivery system was potential carrier for NCTD delivery, and LEH could open opportunities for delivery of poorly soluble anticancer drugs, especially drugs that are more hydrophilicity than lipophilicity.

Endothelial ganglioside GM3 regulates angiogenesis in solid tumors

Cancer cells require oxygen and nutrients for growth, making angiogenesis one of the essential components of tumor growth. Gangliosides, constituting membrane lipid rafts, regulate intracellular signal transduction and are involved in the malignancy of cancer cells. While endothelial cells, as well as cancer cells, express vast amounts of gangliosides, the precise function of endothelial gangliosides in angiogenesis remains unclear. In this study, we focused on gangliosides of vascular endothelial cells and analyzed their functions on tumor angiogenesis. In human breast cancer, GM3 synthase was highly expressed in vascular endothelial cells as well as immune cells. Angiogenesis increased in GM3S-KO mice. In BAEC, RNA interference of GM3S showed increased cellular invasion and oxidative stress tolerance through activation of ERK. In the breast cancer model, GM3-KO mice showed an increase in tumor growth and angiogenesis. These results suggest that the endothelial ganglioside GM3 regulates tumor angiogenesis by suppressing cellular invasion and oxidative stress tolerance in endothelial cells.

Antitumor potential of the protein phosphatase inhibitor, cantharidin, and selected derivatives

Cantharidin is a potent natural protein phosphatase monoterpene anhydride inhibitor secreted by several species of blister beetle, with its demethylated anhydride analogue, (S)-palasonin, occurring as a constituent of the higher plant Butea frondosa. Cantharidin shows both potent protein phosphatase inhibitory and cancer cell cytotoxic activities, but possible preclinical development of this anhydride has been limited thus far by its toxicity. Thus, several synthetic derivatives of cantharidin have been prepared, of which some compounds exhibit improved antitumor potential and may have use as lead compounds. In the present review, the potential antitumor activity, structure-activity relationships, and development of cantharidin-based anticancer drug conjugates are summarized, with protein phosphatase-related and other types of mechanisms of action discussed. Protein phosphatases play a key role in the tumor microenvironment, and thus described herein is also the potential for developing new tumor microenvironment-targeted cancer chemotherapeutic agents, based on cantharidin and its naturally occurring analogues and synthetic derivatives.

Norcantharidin: research advances in pharmaceutical activities and derivatives in recent years

Cantharidin (CTD) is the main bioactive component of Cantharides, which is called Banmao in Traditional Chinese Medicine (TCM). Norcantharidin (NCTD) is a structural modifier of CTD. To compare with CTD, NCTD has lighter side effects and stronger bioactivity in anti-cancer through inhibiting cell proliferation, causing apoptosis and autophagy, overwhelming migration and metastasis, affecting immunity as well as lymphangiogenesis. Examples of these effects include suppressing Protein Phosphatase 2A and modulating Wnt/beta catenin signal, with Caspase family proteins, AMPK pathway and c-Met/EGFR pathway involving respectively. Moreover, NCTD has the effects of immune enhancement, anti-platelet aggregation and inhibition of renal interstitial fibrosis with distinct signaling pathways. The immunological effects induced by NCTD are related to the regulation of macrophage polarization and LPS-mediated immune response. The antiplatelet activity that NCTD induced is relevant to the inhibition of platelet signaling and the downregulation of α2 integrin. Furthermore, some of novel derivatives designed and synthesized artificially show stronger biological activities (e.g., anticancer effect, enzyme inhibition effect, antioxidant effect) and lower toxicity than NCTD itself. Plenty of literatures have reported various pharmacological effects of NCTD, particularly the anticancer effect, which has been widely concerned in clinical application and laboratory research. In this review, the pharmaceutical activities and derivatives of NCTD are discussed, which can be reference for further study.

Insight into norcantharidin, a small-molecule synthetic compound with potential multi-target anticancer activities

Norcantharidin (NCTD) is a demethylated derivative of cantharidin, which is an anticancer active ingredient of traditional Chinese medicine, and is currently used clinically as a routine anti-cancer drug in China. Clarifying the anticancer effect and molecular mechanism of NCTD is critical for its clinical application. Here, we summarized the physiological, chemical, pharmacokinetic characteristics and clinical applications of NCTD. Besides, we mainly focus on its potential multi-target anticancer activities and underlying mechanisms, and discuss the problems existing in clinical application and scientific research of NCTD, so as to provide a potential anticancer therapeutic agent for human malignant tumors.

Sophocarpine Inhibits Tumorgenesis of Colorectal Cancer via Downregulation of MEK/ERK/VEGF Pathway

Colorectal cancer (CRC) is one of the most common malignant tumors and the third leading cause of cancer-related deaths in the world. It was reported that sophocarpine could attenuate the progression of CRC in mice. However, the mechanisms by which sophocarpine regulate the proliferation and migration in CRC remain unclear. Thus, this study aimed to investigate anti-tumor mechanisms of sophocarpine in CRC cells. CCK-8 assay, wound healing assay and transwell migration were used to detect cell proliferation and migration, respectively. In addition, Western blotting and enzyme-linked immunosorbent assay (ELISA) were used to further detect protein expressions and cytokines in vitro. The results revealed that sophocarpine significantly inhibited proliferation in HCT116 and SW620 cells, respectively. Meanwhile, sophocarpine inhibited CRC cells migration via downregulation of the levels of N-cadherin, matrix metalloproteinase (MMP)-9, phosphorylated extracellular signal-regulated kinase (p-ERK), p-mitogen-activated protein kinase kinase (MEK), vascular endothelial growth factor (VEGF)-A, VEGF-C and VEGF-D. Moreover, overexpression of MEK reversed the anti-migration effects of sophocarpine on CRC cells via upregulation of VEGF-A/C/D. Our findings indicated that sophocarpine could inhibit CRC cells migration via downregulation of MEK/ERK/VEGF pathway. Thus, sophocarpine may act as a potential agent for the treatment of CRC.

Downregulation of CKS1B restrains the proliferation, migration, invasion and angiogenesis of retinoblastoma cells through the MEK/ERK signaling pathway

Retinoblastoma (RB) is a common neoplasm that is exhibited in individuals globally. Increasing evidence demonstrated that cyclin‑dependent kinase regulatory subunit 1B (CKS1B) may be involved in the pathogenesis of various tumor types, including multiple myeloma and breast cancer. In the present study, the hypothesis that CKS1B downregulation would effectively inhibit the proliferation, invasion and angiogenesis of RB cells through the mitogen‑activated protein kinase kinase (MEK)/extracellular signal‑regulated kinase (ERK) signaling pathway was examined. Initial investigation of the expression profile of CKS1B in RB and adjacent retina tissues was performed using reverse transcription‑quantitative polymerase chain reaction and western blot analysis. A total of three RB cell lines, SO‑RB50, Y79 and HXO‑RB44, were examined for selection of the cell line with the highest expression of CKS1B, and human normal retinal vascular endothelial cells (ACBRI‑181) were also evaluated. CKS1B short hairpin RNA (shRNA) sequences (shRNA CKS1B‑1, shRNA CKS1B‑2 and shRNA CKS1B‑3) and negative control shRNA sequences were constructed and transfected into cells at the third generation to evaluate the role of shCKS1B and the MEK/ERK signaling pathway in RB. Furthermore, the effect of shCKS1B on cell proliferation, migration, invasion, apoptosis and angiogenesis was investigated. CKS1B was determined to be highly expressed in RB tissue, compared with adjacent retina tissue. SO‑RB50 and HXO‑RB44 cells treated with shRNA CKS1B‑1 and shRNA CKS1B‑2 were selected for the present experiments. Activation of the MEK/ERK signaling pathway increases the expression of MEK, ERK, B‑cell lymphoma 2, proliferating cell nuclear antigen, cyclin D1, vascular endothelia growth factor and basic fibroblast growth factor, enhances cell proliferation, migration, invasion and lumen formation, and decreases apoptosis. Following silencing CKS1B, the aforementioned conditions were reversed. The key observations of the present study demonstrated that shCKS1B can inhibit the proliferation, invasion and angiogenesis of RB cells by suppressing the MEK/ERK signaling pathway. Thus, CKS1B represents a potential research target in the development of therapeutics for RB.

Dual inhibition of Akt and ERK signaling induces cell senescence in triple-negative breast cancer

Activated Akt and ERK signaling pathways are closely related to breast cancer progression, and Akt or ERK inhibition induces cell senescence. However, the crosstalk between the Akt and ERK signaling pathways in cell senescence and how to simultaneously suppress Akt and ERK signaling in triple-negative breast cancer (TNBC) are undefined. In this study, we found that norcantharidin (NCTD) effectively induced cell senescence and cell cycle arrest in TNBC in vitro, which was accompanied by a decline in phosphorylated Akt and ERK1/2 and a rise in p21 and p16. The inhibitors LY294002 and U0126 imitated the effect of NCTD when these two inhibitors were combined regardless of crosstalk between these two signaling pathways. In addition, NCTD inhibited the growth of xenografts via downregulation of phosphorylated Akt and ERK1/2 and upregulation of p21 in vivo. However, NCTD upregulated the level of soluble signaling factors of the senescence-associated secretory phenotype (SASP) in a NF-κB-independent manner. Collectively, these findings demonstrate that NCTD induced cell senescence and cell cycle arrest mainly by simultaneously blocking Akt and ERK signaling in TNBC, suggesting that NCTD may be used as a potential adjuvant therapy in TNBC.

Efficacy and Safety of Aidi Injection Combined with Transcatheter Arterial Chemoembolization on Primary Hepatic Carcinoma: A Systematic Review and Meta-Analysis

Objectives

To evaluate the efficacy and safety of Aidi injection (ADI) combined with transcatheter arterial chemoembolization (TACE) for primary hepatic carcinoma (PHCC).

Methods

We conducted a literature search in EMBASE, PubMed, CENTRAL, MEDLINE, CNKI, Wanfang, and VIP databases from the earliest possible year to April 2018. Randomized controlled trials (RCTs) involving ADI combined with TACE versus TACE alone for patients with PHCC were included. The Cochrane Risk of Bias tool was applied for quality assessment.

Results

22 studies involving 1611 participants were included. The clinical response rate (RR = 1.28, 95% CI: 1.17-1.40; P < 0.00001), KPS score (RR = 1.78, 95% CI: 1.59-2.00; P < 0.00001), survival rate (RR = 1.27, 95% CI: 1.16-1.39; P < 0.00001), immune function (MD = 1.24, 95% CI: 0.98-1.51; P < 0.00001), and adverse effects (RR = 0.62, 95% CI: 0.57-0.68; P < 0.00001) of ADI plus TACE showed significant difference when compared with TACE alone.

Conclusions

ADI combined with TACE in the treatment of PHCC improved the clinical response rate and safety compared to TACE alone. However, due to poor methodological quality of many of the included RCTs, more rigorously designed and large-scale RCTs are warranted to examine this beneficial effect in the future.

Targeting VEGF/VEGFRs Pathway in the Antiangiogenic Treatment of Human Cancers by Traditional Chinese Medicine

Bearing in mind the doctrine of tumor angiogenesis hypothesized by Folkman several decades ago, the fundamental strategy for alleviating numerous cancer indications may be the strengthening application of notable antiangiogenic therapies to inhibit metastasis-related tumor growth. Under physiological conditions, vascular sprouting is a relatively infrequent event unless when specifically stimulated by pathogenic factors that contribute to the accumulation of angiogenic activators such as the vascular endothelial growth factor (VEGF) family and basic fibroblast growth factor (bFGF). Since VEGFs have been identified as the principal cytokine to initiate angiogenesis in tumor growth, synthetic VEGF-targeting medicines containing bevacizumab and sorafenib have been extensively used, but prominent side effects have concomitantly emerged. Traditional Chinese medicines (TCM)–derived agents with distinctive safety profiles have shown their multitarget curative potential by impairing angiogenic stimulatory signaling pathways directly or eliciting synergistically therapeutic effects with anti-angiogenic drugs mainly targeting VEGF-dependent pathways. This review aims to summarize (a) the up-to-date understanding of the role of VEGF/VEGFR in correlation with proangiogenic mechanisms in various tissues and cells; (b) the elaboration of antitumor angiogenesis mechanisms of 4 representative TCMs, including Salvia miltiorrhiza, Curcuma longa, ginsenosides, and Scutellaria baicalensis; and (c) circumstantial clarification of TCM-driven therapeutic actions of suppressing tumor angiogenesis by targeting VEGF/VEGFRs pathway in recent years, based on network pharmacology.

Norcantharidin induce apoptosis in human nasopharyngeal carcinoma through caspase and mitochondrial pathway

While Nasopharyngeal carcinoma (NPC) is uncommon in western countries, it is endemic in Southeast Asia and Southern China. Previous study of norcantharidin (NCTD), isolated from blister beetles, has proved its anticancer effect on various tumors. However, the effect of NCTD in NPC has never been studied. The purpose of this study is to inspect the suppression activity of NCTD on NPC, along with the underlying mechanism. NPC cell line NPC-BM was treated with NCTD. NCTD remarkably inhibited proliferation and induce apoptosis in NPC-BM cell. Activation of caspase-3, -8, -9 was observed through western blotting. The expression of antiapoptotic protein Bcl-XL was significantly reduced, but expression of proapoptotic protein Bak was increased after treatment of NCTD. The cytotoxic effect of NCTD on NPC-BM cell is mainly due to apoptosis, mediated by caspase and mitochondrial pathway. These results suggested that NCTD could be a potential anticancer agent for NPC.

Effect of norcantharidin on the proliferation, apoptosis, and cell cycle of human mesangial cells

AIMS

Norcantharidin (NCTD) regulates immune system function and reduces proteinuria. We sought to investigate the effect of NCTD on proliferation, apoptosis and cell cycle of cultured human mesangial cells (HMC) in vitro.

METHODS

HMC cells were divided into a normal control group, and various concentrations of NCTD group (2.5, 5, 10, 20, or 40 μg/mL). Cell proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, apoptosis was detected by Annexin V/propidium iodide (PI) assays, and morphological analysis was performed by Hoechest 33258 staining. Finally, cell cycle was analyzed by flow cytometry.

RESULTS

NCTD dose and time dependently inhibits HMC proliferation significantly (p < .05). Apoptosis dose and time dependently increased after NCTD treatment. Cell-cycle analysis revealed that the number of cells in the G2 phase increased significantly, whereas the fraction of cells in the S phase decreased, especially 24 h after 5 μg/ml NCTD treatment.

CONCLUSION

NCTD inhibits HMC cell proliferation, induces apoptosis, and affects the cell cycle.

Norcantharidin induces mitochondrial-dependent apoptosis through Mcl-1 inhibition in human prostate cancer cells

Norcantharidin (NCTD) is the demethylated form of cantharidin that exhibits anticancer potential in many cancer cell types. Recent reports suggest that NCTD targeting ROS/AMPK and DNA replication signaling pathway could be an effective strategy for the treatment of PCa cells. However, supportive evidence is limited to the effect of NCTD that induction of apoptosis through suppression of the Mcl-1. Here, we show that NCTD induced PCa cell apoptosis and triggered caspase activation, which was associated with mitochondria dysfunction. Mechanistic investigations suggested that NCTD modulated the Akt signaling via increased nuclear translocation and interaction with the myeloid cell leukemia-1 (Mcl-1) promoter by FOXO4, resulting in an apoptotic effect. Moreover, miR-320d, which targets Mcl-1, was significantly upregulated after NCTD treatment. Overexpression of miR-320d by NCTD induced mitochondria dysfunction and apoptosis, which was notably attenuated with a miR-320d inhibitor. In vivo xenograft analysis revealed that NCTD significantly reduced tumor growth in mice with PC3 tumor xenografts. Taken together, our results provide new insights into the critical role of NCTD in suppressing Mcl-1 via epigenetic upregulation of miR-320d, resulting in PCa cell apoptosis.

ROCK inhibition as a potential therapeutic target involved in apoptosis in hemangioma

Gene expression was examined in hemangiomas (HA), benign, birthmark-like tumors occurring in infancy, and confirmed in HA-derived endothelial cells (HDEC), for which cell proliferation and apoptosis were also assessed. Protein and mRNA accumulation of Rho-associated protein kinase (ROCK), vascular endothelial growth factor (VEGF), Ki-67 and proliferating cell nuclear antigen was significantly higher in proliferating phase HAs than in involuting phase HAs. In contrast, p53 and caspase-3 exhibited higher levels of accumulation in involuting than proliferating HAs. Cell apoptotic indexes were low in proliferating phase HAs and increased in involuting phase HAs. HDECs were treated with the ROCK inhibitor Y-27632. Y-27632 induced p53 expression and downregulated VEGF expression, significantly inhibited cell proliferation, and induced cell apoptosis in HA cells. The inhibitor effects were confirmed in HAs from HDEC-injected nude mice. These results indicated that ROCK is involved in p53-mediated apoptosis and VEGF expression in HA cells and suggested that such inhibition may be exploited for future HA therapies.

Bidirectional regulation of angiogenesis by phytoestrogens through estrogen receptor-mediated signaling networks

Sex hormone estrogen is one of the most active intrinsic angiogenesis regulators; its therapeutic use has been limited due to its carcinogenic potential. Plant-derived phytoestrogens are attractive alternatives, but reports on their angiogenic activities often lack in-depth analysis and sometimes are controversial. Herein, we report a data-mining study with the existing literature, using IPA system to classify and characterize phytoestrogens based on their angiogenic properties and pharmacological consequences. We found that pro-angiogenic phytoestrogens functioned predominantly as cardiovascular protectors whereas anti-angiogenic phytoestrogens played a role in cancer prevention and therapy. This bidirectional regulation were shown to be target-selective and, for the most part, estrogen-receptor-dependent. The transactivation properties of ERα and ERβ by phytoestrogens were examined in the context of angiogenesis-related gene transcription. ERα and ERβ were shown to signal in opposite ways when complexed with the phytoestrogen for bidirectional regulation of angiogenesis. With ERα, phytoestrogen activated or inhibited transcription of some angiogenesis-related genes, resulting in the promotion of angiogenesis, whereas, with ERβ, phytoestrogen regulated transcription of angiogenesis-related genes, resulting in inhibition of angiogenesis. Therefore, the selectivity of phytoestrogen to ERα and ERβ may be critical in the balance of pro- or anti-angiogenesis process.

Norcantharidin Inhibits SK-N-SH Neuroblastoma Cell Growth by Induction of Autophagy and Apoptosis

Norcantharidin, a low-toxic analog of the active anticancer compound cantharidin in Mylabris, can inhibit proliferation and induce apoptosis of multiple types of cancer cells. However, the anticancer activities of norcantharidin with respect to neuroblastoma, and its underlying mechanisms, have not been investigated. Therefore, our study was designed to determine the efficacy of norcantharidin on SK-N-SH neuroblastoma cell death and to elucidate detailed mechanisms of activity. In the present study, norcantharidin suppressed the proliferation and cloning ability of SK-N-SH cells in a dose-dependent manner, apparently by reducing the mitochondrial membrane potential and arresting SK-N-SH cells at the G2/M stage, accompanied by elevated expressions of p21 and decreased expressions of cyclin B1 and cell division control 2. Treatment by norcantharidin induced significant mitophagy and autophagy, as demonstrated by a decrease in Translocase Of Outer Mitochondrial Membrane 20 (TOM20), increased beclin1 and LC3-II protein expression, reduced protein SQSTM1/p62 expression, and accumulation of punctate LC3 in the cytoplasm of SK-N-SH cells. In addition, norcantharidin induced apoptosis through regulating the expression of B-cell lymphoma 2-associated X protein/B-cell lymphoma 2 and B-cell lymphoma 2-associated X protein/myeloid cell leukemia 1 and activating caspase-3 and caspase-9-dependent endogenous mitochondrial pathways. We also observed an increase in phosphor-AMP-activated protein kinase accompanied with a decrease in phosphor-protein kinase B and mammalian target of rapamycin expression after treatment with norcantharidin. Subsequent studies indicated that norcantharidin participates in cellular autophagy and apoptosis via activation of the c-Jun NH2-terminal kinases/c-Jun pathway. In conclusion, our results demonstrate that norcantharidin can reduce the mitochondrial membrane potential, induce mitophagy, and subsequently arouse cellular autophagy and apoptosis; the AMP-activated protein kinase, protein kinase B/mammalian target of rapamycin, and c-Jun NH2-terminal kinases/c-Jun signaling pathways are widely involved in these processes. Thus, the traditional Chinese medicine norcantharidin could be a novel therapeutic strategy for treating neuroblastoma.

Therapeutic targets of Traditional Chinese Medicine for colorectal cancer

OBJECTIVE

To explore the role of Traditional Chinese Medicine (TCM) in the prevention and treatment of colorectal cancer and identify possible therapeutic targets of TCM to provide clues for the use of TCM for colorectal cancer prevention and treatment in the clinic and to find novel directions for new drug discovery for colorectal cancer.

METHODS

We used PubMed and Google to search for and collect scientific publications for a full evalu- ation of current evidence in the literature indicating the potential role of Chinese herbal medicines and their respective ingredients as effective candidates for colorectal cancer prevention and treatment.

RESULTS

We extracted a detailed description of potential therapeutic Chinese herbal medicines and their constituent ingredients that target different mechanisms in colorectal cancer such as gene mutation, dysregulation of signaling pathways, metabolism disorders, and the inflammatory microenvironment, including both conventional and non-conventional approaches.

CONCLUSION

TCM may be a promising complementary and alternative therapy for the treatment of colorectal cancer.

Norcantharidin inhibits renal interstitial fibrosis by downregulating PP2Ac expression

Norcantharidin (NCTD) has been proven to be able to attenuate renal interstitial fibrosis, but the exact molecular mechanism is still unknown. This study investigated the relationship between the anti-fibrotic effect of NCTD and its inhibition on PP2Ac expression. Here, PP2Ac was found to be positively correlated with extracellular matrix accumulation in the rat unilateral ureteral obstruction (UUO) model. Additional experiments showed that the PP2A inhibitor (okadaic acid) can ameliorate renal interstitial fibrosis by inhibiting the expression of fibronectin (FN) and collagen I (Col-I) and reversing tubular epithelial-to-mesenchymal transition in vivo and in vitro. In vitro experiments also demonstrated that ectopic over-expression of PP2Ac has a profibrotic effect in HK-2 cells. Moreover, NCTD was able to downregulate PP2Ac expression, decrease FN, Col-I, α-SMA expression, and increase E-cadherin expression in a dose-dependent manner both in vivo and in vitro. In particular, it was demonstrated that NCTD induced no evident changes in the expression of FN, Col-I, α-SMA and E-cadherin in HK-2 cells after PP2Ac was knocked down by shRNA. These results indicated that NCTD exerts an anti-fibrosis effect via inhibition of PP2Ac expression. Thus, PP2Ac could be a promising target for intervention in renal interstitial fibrosis.

Intraarterial administration of norcantharidin attenuates ischemic stroke damage in rodents when given at the time of reperfusion: novel uses of endovascular capabilities

OBJECT Matrix metalloprotease-9 (MMP-9) plays a critical role in infarct progression, blood-brain barrier (BBB) disruption, and vasogenic edema. While systemic administration of MMP-9 inhibitors has shown neuroprotective promise in ischemic stroke, there has been little effort to incorporate these drugs into endovascular modalities. By modifying the rodent middle cerebral artery occlusion (MCAO) model to allow local intraarterial delivery of drugs, one has the ability to mimic endovascular delivery of therapeutics. Using this model, the authors sought to maximize the protective potential of MMP-9 inhibition by intraarterial administration of an MMP-9 inhibitor, norcantharidin (NCTD). METHODS Spontaneously hypertensive rats were subjected to 90-minute MCAO followed immediately by local intraarterial administration of NCTD. The rats' neurobehavioral performances were scored according to the ladder rung walking test results and the Garcia neurological test for as long as 7 days after stroke. MRI was also conducted 24 hours after the stroke to assess infarct volume and BBB disruption. At the end of the experimental protocol, rat brains were used for active MMP-9 immunohistochemical analysis to assess the degree of MMP-9 inhibition. RESULTS NCTD-treated rats showed significantly better neurobehavioral scores for all days tested. MR images also depicted significantly decreased infarct volumes and BBB disruption 24 hours after stroke. Inhibition of MMP-9 expression in the ischemic region was depicted on immunohistochemical analysis, wherein treated rats showed decreased active MMP-9 staining compared with controls. CONCLUSIONS Intraarterial NCTD significantly improved outcome when administered at the time of reperfusion in a spontaneously hypertensive rat stroke model. This study suggests that supplementing endovascular revascularization with local neuroprotective drug therapy may be a viable therapeutic strategy.

Recent highlights of experimental research for inhibiting tumor growth by using Chinese medicine

To give an overview of contemporary experimental research using Chinese medicine (CM) for the treatment of cancer. As an integral part of mainstream medicine in the People's Republic of China, CM emphasizes improvements in holistic physical condition instead of merely killing tumor cells, which is consistent with the current medical model that advocates patient-oriented treatment. Great progress has been made in experimental research, and the principle aspects include anti-tumor angiogenesis, inducing apoptosis and differentiation, reversing multidrug resistance, and improving immune function. As a current hot topic in cancer research, tumor microenvironment (TME) highlights the mutual and interdependent interaction between tumor cells and their surrounding tissues, and the CM treatment concept bears a striking resemblance to it. To date, primary points of TME include extracellular matrix remodeling, inflammation, hypoxia, and angiogenesis, but trials using CM with a focus on TME are rare. Despite considerable recent development, experimental research on CM for solving cancer issues appears insufficient. Greater efforts in this field are urgently needed.

A potential small-molecule synthetic antilymphangiogenic agent norcantharidin inhibits tumor growth and lymphangiogenesis of human colonic adenocarcinomas through blocking VEGF-A,-C,-D/VEGFR-2,-3 "multi-points priming" mechanisms in vitro and in vivo

Background

Tumor lymphangiogenesis plays an important role in promoting growth and metastasis of tumors, but no antilymphangiogenic agent is used clinically. Based on the effect of norcantharidin (NCTD) on lymphangiogenesis of human lymphatic endothelial cells (LECs), we firstly investigated the antilymphangiogenic activity of NCTD as a tumor lymphangiogenic inhibitor for human colonic adenocarcinomas (HCACs).

Methods

In vivo and in vitro experiments to determine the effects of NCTD on tumor growth and lymphangiogenesis of the in-situ colonic xenografts in nude mice, and lymphatic tube formation of the three-dimensional (3-D) of the co-culture system of HCAC HT-29 cells and LECs were done. Proliferation, apoptosis, migration, invasion, Ki-67, Bcl-2 and cell cycle of LECs and the co-culture system in vitro were respectively determined. Streparidin-peroxidase staining, SABC, western blotting and RT-PCR were respectively used to examine the expression of LYVE-1, D2-40, CK20 (including their LMVD), and VEGF-A, VEGF-C, VEGF-D, VEGFR-2 and VEGFR-3 in vitro and in vivo.

Results

NCTD inhibited tumor growth and lymphangiogenesis of the in-situ colonic xenografts in vivo, and these observations were confirmed by facts that lymphatic tube formation, proliferation, apoptosis, migration, invasion, S-phase cell cycle, and Ki-67 and Bcl-2 expression in vitro, and LYVE-1, D2-40, CK20 expression and their LMVD in vitro and in vivo were inhibited and affected. Furthermore, the expression of VEGF-A, VEGF-C, VEGF-D, VEGFR-2 and VEGFR-3 at protein/mRNA levels in the process of lymphatic tube formation in vitro and tumor lymphangiogenesis in vivo was downregulated; NCTD in combination with mF4-31C1 or Sorafenib enhanced these effects.

Conclusions

NCTD inhibits tumor growth and lymphangiogenesis of HCACs through “multi-points priming” mechanisms i.e. affecting related malignant phenotypes, inhibiting Ki-67 and Bcl-2 expression, inducing S-phase cell cycle arrest, and directly or indirectly downregulating VEGF-A,-C,-D/VEGFR-2,-3 signaling pathways. The present finding strongly suggests that NCTD could serve as a potential antilymphangiogenic agent for tumor lymphangiogenesis and is of importance to explore NCTD is used for antitumor metastatic comprehensive therapy for HCACs.

Berberine Inhibits Invasion and Metastasis of Colorectal Cancer Cells via COX-2/PGE2 Mediated JAK2/STAT3 Signaling Pathway

Berberin, extracted from Chinese herbal medicine Coptis chinensis, has been found to have anti-tumor activities. However, the underlying mechanisms have not been fully elucidated. Our current study demonstrated that berberin inhibited the in vitro and in vivo growth, migration/invasion of CRC cells, via attenuating the expression levels of COX-2/PGE₂, following by reducing the phosphorylation of JAK2 and STAT3, as well as the MMP-2/-9 expression. We further clarified that an increase of COX-2/PGE₂ expression offset the repressive activity of Berberin on JAK2/STAT3 signaling, and a JAK2 inhibitor AZD1480 blocked the effect of COX-2/PGE₂ on MMP-2/-9 expression. In summary, Berberin inhibited CRC invasion and metastasis via down-regulation of COX-2/PGE₂- JAK2/STAT3 signaling pathway.

Water extract of Cinnamomum cassia suppresses angiogenesis through inhibition of VEGF receptor 2 phosphorylation

Angiogenesis, the process of new blood vessel formation, has been a major target for cancer therapy. Antiangiogenic herbal medicines are useful in the treatment of cancer. In this study, we found that a water extract of Cinnamomum cassia (CCWE) was a potent inhibitor of angiogenesis. In cultured human umbilical vein endothelial cells, CCWE suppressed vascular endothelial growth factor (VEGF)-induced proliferation, migration, invasion, tube formation, and intracellular signaling events such as phosphorylation of ERK, p38 and VEGFR2, and activation of matrix metalloproteinase. Furthermore, CCWE inhibited VEGF-induced vessel sprouting of rat aorta ex vivo. These findings might be of particular interest for drug development because VEGF signaling is a potential target for treatment of angiogenesis-associated diseases.

Norcantharidin inhibits Wnt signal pathway via promoter demethylation of WIF-1 in human non-small cell lung cancer

Wingless-type (Wnt) family of secreted glycoproteins is a group of signal molecules implicated in oncogenesis. Abnormal activation of Wnt signal pathway is associated with a variety of human cancers, including non-small cell lung cancer (NSCLC). Wnt antagonists, such as the secreted frizzled-related protein (SFRP) family, Wnt inhibitory factor-1 (WIF-1) and cerberus, inhibit Wnt signal pathway by directly binding to Wnt molecules. Norcantharidin (NCTD) is known to possess anticancer activity but less nephrotoxicity than cantharidin. In this study, we found that NCTD inhibited cell proliferation, induced apoptosis, arrested cell cycle and suppressed cell invasion/migration in vitro. Additionally, Wnt signal pathway transcription was also suppressed. NCTD treatment blocked cytoplasmic translocation of beta-catenin into the nucleus. Alterations of apoptosis-related proteins, such as Bax, cleaved caspase-3 (pro-apoptotic) and Bcl-2 (anti-apoptotic), had been detected. Furthermore, the expression levels of WIF-1 and SFRP1 were significantly increased in NCTD-treated groups compared with negative control (NC) groups. Abnormal methylation was observed in NC groups, while NCTD treatment promoted WIF-1 demethylation. The present study revealed that NCTD activated WIF-1 via promoter demethylation, inhibiting the canonical Wnt signal pathway in NSCLC, which may present a new therapeutic target in vivo.

Prospects for multitarget lipid-raft-coated silica beads: a remarkable online biomaterial for discovering multitarget antitumor lead compounds

Application of lipid raft biomaterial with multiple cancer-related receptors for screening novel multitarget antitumour lead compounds.

Norcantharidin induces growth inhibition and apoptosis of glioma cells by blocking the Raf/MEK/ERK pathway

Background

Malignant gliomas represent the most common primary brain tumors. The prognosis of patients with malignant gliomas is poor in spite of current intensive therapy and novel therapeutic modalities are needed. Here we report that norcantharidin is effective in growth inhibition of glioma cell lines in vitro.

Methods

Glioma cell lines (U87 and C6) were treated with norcantharidin. The effects of norcantharidin on the proliferation and apoptosis of glioma cells were measured by 3-[4,5-dimethylthiazol-2-thiazolyl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and flow cytometry. Western blotting was employed to determine the signaling pathway changes.

Results

The results showed that norcantharidin effectively inhibited cell growth and induced apoptosis in glioma cells, which was concurrent with inhibition of the expression of phospho-MEK and phospho-ERK. Furthermore, the expression anti-apoptotic proteins Bcl-2 and Mcl-1 significantly reduced, but no changes in Bcl-xL and Bax.

Conclusions

Our findings demonstrate that norcantharidin is effective for growth inhibition of glioma cell lines and suggest that norcantharidin may be a new therapeutic option for patients with glioma.

Knockdown of VEGFR2 inhibits proliferation and induces apoptosis in hemangioma-derived endothelial cells

Angiogenesis is a process of development and growth of new capillary blood vessels from pre-existing vessels. Angiogenic growth factors play important roles in the development and maintenance of some malignancies, of which vascular endothelial growth factor (VEGF)/VEGFR2 interactions are involved in proliferation, migration, and survival of many cancer cells. The aim of this study was to investigate the function of VEGFR2 in human hemangiomas (HAs). Using immunohistochemistry assay, we examined the expression levels of VEGF, VEGFR2, Ki-67, glucose transporter-1 (Glut-1), phosphorylated protein kinase B (p-AKT) and p-ERK in different phases of human HAs. Positive expression of VEGF, VEGFR2, Ki-67, Glut-1, p-AKT and p-ERK was significantly increased in proliferating phase HAs, while decreased in involuting phase HAs (P=0.001; P=0.003). In contrast, cell apoptotic indexes were decreased in proliferating phase HAs, but increased in involuting phase HAs (P&lt;0.01). Furthermore, we used small hairpin RNA (shRNA)-mediated VEGFR2 knockdown in primary HA-derived endothelial cells (HemECs) to understand  the  role  of  VEGF/VEGFR2 signaling. Knockdown of VEGFR2 by Lv-shVEGFR2 inhibited cell viability and induced apoptosis in primary HemECs companied with decreased expression of p-AKT, p-ERK, p-p38MAPK and Ki-67 and increased expression of caspase-3 (CAS-3). Overexpression of VEGFR2 promoted cell viability and blocked apoptosis in Lv-VEGFR2-transfected HemECs. Taken together, our findings demonstrate that, increased expression of VEGFR2 is involved in the development of primary HemECs possibly through regulation of the AKT and ERK pathways, suggesting that VEGFR2 may be a potential therapeutic target for HAs. 

Norcantharidin inhibits tumor angiogenesis via blocking VEGFR2/MEK/ERK signaling pathways

Norcantharidin (NCTD), the demethylated form of Cantharidin, a reagent isolated from blister beetles, has been shown to be an anti-tumor agent capable of inhibiting proliferation as well as inducing apoptosis in many cancer cell lines. However, little is known about the effect of NCTD in tumor angiogenesis. In this study, we demonstrated that NCTD inhibited vascular endothelial growth factor (VEGF)-induced cell proliferation, migration, invasion, and capillary tube formation of primary human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner. Furthermore, we showed NCTD inhibited tumor growth and angiogenesis of colon cancer cells (LOVO) in vivo. We then mechanistically described that NCTD specifically abrogated the phosphorylation/activation of vascular endothelial growth factor receptor-2 (VEGFR2)/MEK/ERK pathway kinases, with little effect on the phosphorylation of p38 MAPK and Akt, and on Cox-2 expression. In summary, our results indicate that NCTD is a potential inhibitor of tumor angiogenesis by blocking VEGFR2/MEK/ERK signaling.