Pharmacotherapeutic values of berberine: A Chinese herbal medicine for the human cancer management.

Berberine (BBR), a traditional Chinese phytomedicine extracted from various parts of Berberis plants, is an isoquinoline alkaloid used for centuries to treat diabetes, hypercholesterolemia, hypertension, and so forth. It has recently received immense attention worldwide to treat cancer due to its potent pro-apoptotic, antiproliferative, and anti-inflammatory properties. BBR efficiently induces tumor apoptosis, replicative quiescence and abrogates cell proliferation, epithelial-mesenchymal transition, tumor neovascularization, and metastasis by modulating diverse molecular and cell signaling pathways. Furthermore, BBR could also reverse drug resistance, make tumor cells sensitive to current cancer treatment and significantly minimize the harmful side effects of cytotoxic therapies. This review comprehensively analyzed the pharmacological effects of BBR against the development, growth, progression, metastasis, and therapy resistance in wide varieties of cancer. Also, it critically discusses the significant limitations behind the development of BBR into pharmaceuticals to treat cancer and the future research directions to overcome these limitations.

Platycodin D Inhibits Vascular Endothelial Growth Factor-Induced Angiogenesis by Blocking the Activation of Mitogen-Activated Protein Kinases and the Production of Interleukin-8.

Platycodin D is a major constituent in the root of Platycodon grandiflorum and has diverse pharmacologic activities, including anti-inflammatory, anti-allergic, and antitumor activities. Vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) are potent angiogenic factors and contribute to tumor angiogenesis by directly and indirectly promoting angiogenic processes, including the proliferation, adhesion, migration, and tube formation of endothelial cells. Here, we found that platycodin D at noncytotoxic concentrations inhibited VEGF-induced proliferation, adhesion to the extracellular matrix proteins fibronectin and vitronectin, chemotactic motility, and tube formation of human umbilical vein endothelial cells (HUVECs). Platycodin D reduced the phosphorylation of extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal kinase (JNK) and the secretion of IL-8 in VEGF-stimulated HUVECs. Moreover, platycodin D inhibited tube formation and the phosphorylation of ERK and p38 in IL-8-stimulated HUVECs. The in vitro anti-angiogenic activity of platycodin D was confirmed by in vivo experimental models. Platycodin D inhibited the formation of new blood vessels into mouse Matrigel plugs with VEGF or IL-8. In mice injected with MDA-MB-231 human breast cancer cells, orally administered platycodin D inhibited tumor growth, the number of CD34 [Formula: see text]vessels, and the expression of VEGF and IL-8. Taken together, platycodin D directly and indirectly prevents VEGF-induced and IL-8-induced angiogenesis by blocking the activation of mitogen-activated protein kinases (MAPKs). Platycodin D may be beneficial for the prevention or treatment of tumor angiogenesis and angiogenesis-related human diseases.

Ethnopharmacological evaluation of antioxidant, anti-angiogenic, and anti-inflammatory activity of some traditional medicinal plants used for treatment of cancer in Togo/Africa.

ETHNOPHARMACOLOGICAL RELEVANCE: Cancer is a multistep disease and its management is exceedingly expensive. Nowadays medicinal plants are gaining more attention in drug discovery and approximately 70% of anticancer drugs were developed from natural products or plants. A strong candidate from medicinal plant with anticancer potential should have four major properties: antioxidant, anti-inflammatory, anti-angiogenic, and cytotoxic activities. AIM OF THE STUDY: In order to assess Togolese traditional healer's claims about the anticancer potential of medicinal plants and obtain candidate plants for anticancer drug discovery, some species were selected from surveys and evaluated for their antioxidant, anti-inflammatory, anti-angiogenic and cytotoxic activities. METHODS: Four species, Cochlospermum planchonii (CP), Piliostigma thonningii (PT), Paullinia pinnata (PP), and Securidaca longipedunculata (SL) were selected and analyzed to detect the phytochemical components. The mentioned bioactivities were evaluated using in vitro, ex vivo and in vivo assays. RESULTS: Relative to SL extract, CP and PT have shown significantly high polyphenols and flavonoids content. The DPPH, FRAP, and TAC of the extracts revealed that CP, PT, and PP have a potent antioxidant effect compared to SL. MDA analysis revealed the same antioxidant activity as CP, PT and PP showed a minor MDA level. The egg albumin denaturation assay showed that IC50 of CP and PP was significantly higher than control (P < 0.05). In contrast, the Bovine Serum Albumin (BSA) results showed a nonsignificant effect (P > 0.05). Notably, SL extract was nonsignificant to control in both Egg Albumin and BSA. Furthermore, angiogenesis assay showed that SL at 50 µg/ml and PP at 100 µg/ml effectively reduced the number of blood vessels than control and showed a potent anti-angiogenic effect (2.7-fold and 2.5-fold, respectively, P < 0.05). No cytotoxicity on PBMC was reported for CP, PP, and PT up to 1000 µg/ml, whereas SL at 1000 µg/ml exhibit benign cytotoxicity (P < 0.0001). CONCLUSION: This study provided in vitro evidence supporting further evaluation on cancer cell lines and tumors in vivo.

Targeting the Ang2/Tie2 Axis with Tanshinone IIA Elicits Vascular Normalization in Ischemic Injury and Colon Cancer.

Pathological angiogenesis, as exhibited by aberrant vascular structure and function, has been well deemed to be a hallmark of cancer and various ischemic diseases. Therefore, strategies to normalize vasculature are of potential therapeutic interest in these diseases. Recently, identifying bioactive compounds from medicinal plant extracts to reverse abnormal vasculature has been gaining increasing attention. Tanshinone IIA (Tan IIA), an active component of Salvia miltiorrhiza, has been shown to play significant roles in improving blood circulation and delaying tumor progression. However, the underlying mechanisms responsible for the therapeutic effects of Tan IIA are not fully understood. Herein, we established animal models of HT-29 human colon cancer xenograft and hind limb ischemia to investigate the role of Tan IIA in regulating abnormal vasculature. Interestingly, our results demonstrated that Tan IIA could significantly promote the blood flow, alleviate the hypoxia, improve the muscle quality, and ameliorate the pathological damage after ischemic insult. Meanwhile, we also revealed that Tan IIA promoted the integrity of vascular structure, reduced vascular leakage, and attenuated the hypoxia in HT-29 tumors. Moreover, the circulating angiopoietin 2 (Ang2), which is extremely high in these two pathological states, was substantially depleted in the presence of Tan IIA. Also, the activation of Tie2 was potentiated by Tan IIA, resulting in decreased vascular permeability and elevated vascular integrity. Mechanistically, we uncovered that Tan IIA maintained vascular stability by targeting the Ang2-Tie2-AKT-MLCK cascade. Collectively, our data suggest that Tan IIA normalizes vessels in tumors and ischemic injury via regulating the Ang2/Tie2 signaling pathway.

Largazole Inhibits Ocular Angiogenesis by Modulating the Expression of VEGFR2 and p21.

Ocular angiogenic diseases, characterized by abnormal blood vessel formation in the eye, are the leading cause of blindness. Although Anti-VEGF therapy is the first-line treatment in the market, a substantial number of patients are refractory to it or may develop resistance over time. As uncontrolled proliferation of vascular endothelial cells is one of the characteristic features of pathological neovascularization, we aimed to investigate the role of the class I histone deacetylase (HDAC) inhibitor Largazole, a cyclodepsipeptide from a marine cyanobacterium, in ocular angiogenesis. Our study showed that Largazole strongly inhibits retinal vascular endothelial cell viability, proliferation, and the ability to form tube-like structures. Largazole strongly inhibits the vessel outgrowth from choroidal explants in choroid sprouting assay while it does not affect the quiescent choroidal vasculature. Largazole also inhibits vessel outgrowth from metatarsal bones in metatarsal sprouting assay without affecting pericytes coverage. We further demonstrated a cooperative effect between Largazole and an approved anti-VEGF drug, Alflibercept. Mechanistically, Largazole strongly inhibits the expression of VEGFR2 and leads to an increased expression of cell cycle inhibitor, p21. Taken together, our study provides compelling evidence on the anti-angiogenic role of Largazole that exerts its function through mediating different signaling pathways.

Vascular Endothelial Growth Factor, a Key Modulator of the Anti-Tumor Immune Response.

During tumor growth, angiogenesis is required to ensure oxygen and nutrient transport to the tumor. Vascular endothelial growth factor (VEGF) is the major inducer of angiogenesis and appears to be a key modulator of the anti-tumor immune response. Indeed, VEGF modulates innate and adaptive immune responses through direct interactions and indirectly by modulating protein expressions on endothelial cells or vascular permeability. The inhibition of the VEGF signaling pathway is clinically approved for the treatment of several cancers. Therapies targeting VEGF can modulate the tumor vasculature and the immune response. In this review, we discuss the roles of VEGF in the anti-tumor immune response. In addition, we summarize therapeutic strategies based on its inhibition, and their clinical approval.

Selenium nanoparticles with various morphology for antiangiogenesis through bFGF-mediated P13K/AKT signaling pathways.

Selenium nanoparticles (Se NPs) have potential antitumor activity and immune properties. However, the mechanism between its antitumor activity and nanoparticle morphology has not been evaluated. Therefore, a simple method was used to synthesize three special shapes of Se NPs, which are fusiform, flower and spherical. Compared with fusiform selenium nanoparticles (Se NPs (S)) and flower-shaped selenium nanoparticles (Se NPs (F)), spherical selenium nanoparticles (Se NPs (B)) have better cell absorption effect and stronger antitumor activity. HRTEM showed that Se NPs (B) entered the nucleus through endocytosis and inhibited tumor angiogenesis by targeting basic fibroblast growth factor (bFGF). Se NPs (B) can competitively inhibit the binding of bFGF to fibroblast growth factor receptor through direct binding to bFGF, down-regulate the expression of bFGF in human umbilical vein endothelial cells (HUVEC), and significantly reduce the MAPK/Erk and P13K/AKT pathways activation of signaling molecules to regulate HUVEC cell migration and angiogenesis. These findings indicate that Se NPs have a special role in antitumor angiogenesis. This research provides useful information for the development of new strategies for effective drug delivery nanocarriers and therapeutic systems.

Moscatilin Inhibits Metastatic Behavior of Human Hepatocellular Carcinoma Cells: A Crucial Role of uPA Suppression via Akt/NF-κB-Dependent Pathway.

Hepatocellular carcinoma (HCC) frequently shows early invasion into blood vessels as well as intrahepatic metastasis. Innovations of novel small-molecule agents to block HCC invasion and subsequent metastasis are urgently needed. Moscatilin is a bibenzyl derivative extracted from the stems of a traditional Chinese medicine, orchid Dendrobium loddigesii. Although moscatilin has been reported to suppress tumor angiogenesis and growth, the anti-metastatic property of moscatilin has not been elucidated. The present results revealed that moscatilin inhibited metastatic behavior of HCC cells without cytotoxic fashion in highly invasive human HCC cell lines. Furthermore, moscatilin significantly suppressed the activity of urokinase plasminogen activator (uPA), but not matrix metalloproteinase (MMP)-2 and MMP-9. Interestingly, moscatilin-suppressed uPA activity was through down-regulation the protein level of uPA, and did not impair the uPA receptor and uPA inhibitory molecule (PAI-1) expressions. Meanwhile, the mRNA expression of uPA was inhibited via moscatilin in a concentration-dependent manner. In addition, the expression of phosphorylated Akt, rather than ERK1/2, was inhibited by moscatilin treatment. The expression of phosphor-IκBα, and -p65, as well as κB-luciferase activity were also repressed after moscatilin treatment. Transfection of constitutively active Akt (Myr-Akt) obviously restored the moscatilin-inhibited the activation of NF-κB and uPA, and cancer invasion in HCC cells. Taken together, these results suggest that moscatilin impedes HCC invasion and uPA expression through the Akt/NF-κB signaling pathway. Moscatilin might serve as a potential anti-metastatic agent against the disease progression of human HCC.

Xanthorrhizol Suppresses Vascular Endothelial Growth Factor-Induced Angiogenesis by Modulating Akt/eNOS Signaling and the NF-[Formula: see text]B-Dependent Expression of Cell Adhesion Molecules.

Angiogenesis plays a crucial role in tumor growth and metastasis. Vascular endothelial growth factor (VEGF)-stimulated endothelial cell proliferation and migration are critical steps in tumor angiogenesis. Here, we investigated the anti-angiogenic activity of xanthorrhizol, a sesquiterpenoid isolated from the Indonesian medicinal plant Curcuma xanthorrhiza. Xanthorrhizol at noncytotoxic concentrations inhibited the proliferation, migration, and formation of capillary-like tubes in VEGF-treated human umbilical vein endothelial cells (HUVECs). Xanthorrhizol inhibited the phosphorylation of Akt and endothelial nitric oxide synthase (eNOS) and the expression of vascular cell adhesion molecule (VCAM)-1 and E-selectin in VEGF-treated HUVECs. The expression and transcriptional activity of NF-[Formula: see text]B were downregulated by xanthorrhizol in VEGF-treated HUVECs. Furthermore, xanthorrhizol significantly inhibited VEGF-induced angiogenesis in the chorioallantoic membrane of fertilized eggs and Matrigel plugs subcutaneously injected into mice. Xanthorrhizol inhibited tumor volume and tumor-derived angiogenesis in mice inoculated with breast cancer cells. The in vitro and in vivo anti-angiogenic activities of xanthorrhizol were as potent as those of curcumin, a well-known anticancer agent derived from C. longa. Taken together, xanthorrhizol inhibits VEGF-induced angiogenesis of endothelial cells by blocking the activation of the PI3K/Akt/eNOS axis and subsequent upregulation of adhesion molecules induced by the transcriptional activation of NF-[Formula: see text]B. Xanthorrhizol is a promising anti-angiogenic agent and can serve as a beneficial agent to enhance anticancer treatments.

Autophagy-induced p62 accumulation is required for curcumol to regulate KLF5-mediated angiogenesis in liver sinusoidal endothelial cells.

Liver pathological angiogenesis is considered to be one of the key events in the development of liver fibrosis. Autophagy is a defense and stress regulation mechanism. However, whether autophagy regulates pathological angiogenesis in liver fibrosis is still questionable. Here, we aimed to study how curcumol regulated liver sinusoidal endothelial cells (LSECs) angiogenesis through autophagy. We found that curcumol (10, 20 and 40 µM) could inhibit the expression of angiogenesis markers in the LSECs. Importantly, we showed that curcumol might influence LSEC pathological angiogenesis by regulating autophagy level. Furthermore, we indicated that the transcription factor Krüppel-like factor 5 (KLF5) was considered as a key target for curcumol to regulate LSEC angiogenesis. Interestingly, we also suggested that autophagy was as a potential mechanism for curcumol to restrain KLF5 expression. Increased autophagy level could impair the suppression effect of curcumol on KLF5. Fascinatingly, our results indicated that curcumol inhibited autophagy and led to p62 accumulation, which might be a regulation mechanism of KLF5 degradation. Finally, in mice liver fibrosis model, we unanimously showed that curcumol (30 mg/kg) inhibited pathological angiogenesis by reducing LSEC autophagy level and suppressing KLF5 expression. Collectively, these results provided a deeper insight into the molecular mechanism of curcumol to inhibit LSEC pathological angiogenesis during liver fibrosis.