Wogonin suppresses melanoma cell B16-F10 invasion and migration by inhibiting Ras-medicated pathways

Targeting extracellular matrix through phytochemicals: a promising approach of multi-step actions on the treatment and prevention of cancer

Extracellular matrix (ECM) plays a pivotal and dynamic role in the construction of tumor microenvironment (TME), becoming the focus in cancer research and treatment. Multiple cell signaling in ECM remodeling contribute to uncontrolled proliferation, metastasis, immune evasion and drug resistance of cancer. Targeting trilogy of ECM remodeling could be a new strategy during the early-, middle-, advanced-stages of cancer and overcoming drug resistance. Currently nearly 60% of the alternative anticancer drugs are derived from natural products or active ingredients or structural analogs isolated from plants. According to the characteristics of ECM, this manuscript proposes three phases of whole-process management of cancer, including prevention of cancer development in the early stage of cancer (Phase I); prevent the metastasis of tumor in the middle stage of cancer (Phase II); provide a novel method in the use of immunotherapy for advanced cancer (Phase III), and present novel insights on the contribution of natural products use as innovative strategies to exert anticancer effects by targeting components in ECM. Herein, we focus on trilogy of ECM remodeling and the interaction among ECM, cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs), and sort out the intervention effects of natural products on the ECM and related targets in the tumor progression, provide a reference for the development of new drugs against tumor metastasis and recurrence.

An immunomodulating peptide to counteract solar radiation-induced immunosuppression and DNA damage

Ultraviolet radiation (UVR) induces immunosuppression and DNA damage, both of which contribute to the rising global incidence of skin cancer including melanoma. Nucleotide excision repair, which is activated upon UVR-induced DNA damage, is linked to expression of interleukin-12 (IL-12) which serves to limit immunosuppression and augment the DNA repair process. Herein, we report an immunomodulating peptide, designated IK14800, that not only elicits secretion of IL-12, interleukin-2 (IL-2) and interferon-gamma (IFN-γ) but also reduces DNA damage in the skin following exposure to UVR. Combined with re-invigoration of exhausted CD4+ T cells, inhibition of UVR-induced MMP-1 release and suppression of B16F10 melanoma metastases, IK14800 offers an opportunity to gain further insight into mechanisms underlying the development and progression of skin cancers.

Deciphering the Mechanism of Wogonin, a Natural Flavonoid, on the Proliferation of Pulmonary Arterial Smooth Muscle Cells by Integrating Network Pharmacology and In Vitro Validation

Wogonin is one of the main active components of Scutellaria baicalensis, which has anti-inflammatory, anti-angiogenesis, and anti-fibrosis effects. Nevertheless, the effect of wogonin on pulmonary hypertension (PH) still lacks systematic research. This study aims to elucidate the potential mechanism of wogonin against PH through network pharmacology and further verify it through biological experiments in pulmonary arterial smooth muscle cells (PASMCs). The potential targets and pathways of wogonin against PH were predicted and analyzed by network pharmacology methods and molecular docking technology. Subsequently, the proliferation of PASMCs was induced by platelet-derived growth factor-BB (PDGF-BB). Cell viability and migration ability were examined. The method of Western blot was adopted to analyze the changes in related signaling pathways. Forty potential targets related to the effect of wogonin against PH were obtained. Based on the protein-protein interaction (PPI) network, gene-ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment, and molecular docking, it was shown that the effect of wogonin against PH is closely related to the proliferation of PASMCs and the hypoxia-inducible factor-1α (HIF-1α) pathway. A variety of results from biological experiments verified that wogonin can effectively inhibit the proliferation, migration, and phenotypic transformation of PDGF-BB-mediated PASMCs. In addition, the anti-proliferation effect of wogonin may be achieved by regulating HIF-1/ NADPH oxidase 4 (NOX4) pathway.

The Interplay between Tumour Microenvironment Components in Malignant Melanoma

Malignant melanoma has shown an increasing incidence during the last two decades, exhibiting a large spectrum of locations and clinicopathological characteristics. Although current histopathological, biochemical, immunohistochemical, and molecular methods provide a deep insight into its biological behaviour and outcome, melanoma is still an unpredictable disease, with poor outcome. This review of the literature is aimed at updating the knowledge regarding melanoma’s clinicopathological and molecular hallmarks, including its heterogeneity and plasticity, involving cancer stem cells population. A special focus is given on the interplay between different cellular components and their secretion products in melanoma, considering its contribution to tumour progression, invasion, metastasis, recurrences, and resistance to classical therapy. Furthermore, the influences of the specific tumour microenvironment or “inflammasome”, its association with adipose tissue products, including the release of “extracellular vesicles”, and distinct microbiota are currently studied, considering their influences on diagnosis and prognosis. An insight into melanoma’s particular features may reveal new molecular pathways which may be exploited in order to develop innovative therapeutic approaches or tailored therapy.

“MYH9 mutation and squamous cell cancer of the tongue in a young adult: a novel case report”

Background

The incidence of tongue cancer in young adults is on the rise. This trend is more pronounced in females. Although the aetiology is still unclear, there is mounting evidence that genetic syndromes can play a key role in development of oral cancers in this patient group. We report the first case of oral squamous cell carcinoma (oSCC) in a young adult with an MYH9-related disorder (MYH9-RD).

Case presentation

A 19-year-old female with a germline MYH9 variant (missense variant in exon 2: c.287C > T, (p.Ser96Leu)) was referred to the head and neck surgery department for investigation of a painful, thick right tongue ulcer. She was diagnosed with Epstein syndrome, an MYH9-RD, at 12 years of age. Her main phenotypic features were profound thrombocytopenia and marked renal impairment. The tongue biopsy confirmed SCC. Preoperative positron emission tomography (PET) revealed avidity in the right tongue and ipsilateral level 2A neck lymph node. With substantial preoperative multidisciplinary input, she underwent cancer ablation and microvascular free flap reconstruction. Her pathology showed a 35 mm diameter, 14 mm thick moderately differentiated SCC with perineural and lymphovascular invasion. Two out of 38 right neck nodes were positive for metastasis with extranodal extension. None of the 34 left neck nodes was involved.

She had an uneventful recovery and was discharged home on day 6 postoperative day. On day 15 postoperative day, she had catastrophic bleeding in the neck with a respiratory arrest after a forceful cough. She required an emergency tracheostomy and returned to the theatre for haemostasis. Following a short inpatient stay, she was again discharged home and underwent adjuvant therapy consisting of external beam radiotherapy of 60Gy in 30 fractions. On clinical examination and PET at 6 months after surgery, she had no evidence of disease recurrence.

Conclusions

MYH9-RD can present with advanced locoregional oral cavity malignancy at an early age. The combination of profound thrombocytopenia and marked renal impairment can impact heavily on routine major head and neck cancer surgery and adjuvant treatment. This rare and challenging condition underlines the importance of early detection of cancer and multidisciplinary team input.

Antiproliferative Wnt inhibitor wogonin prevents eryptosis following ionophoric challenge, hyperosmotic shock, oxidative stress, and metabolic deprivation

Anemia is a common complication of chemotherapy and may arise due to premature or suicidal death of red blood cells (RBCs). Prevention of RBC death thus lends itself as a promising strategy to counteract anemia. Wogonin (WGN; 5,7-dihydroxy-8-methoxyflavone) is a Wnt inhibitor derived from Scutellaria baicalensis plant with potent cytotoxic and antitumor potential. However, the nature of interaction of WGN with human RBCs is unknown. RBCs from healthy participants were exposed to different hemolytic and eryptotic stimuli for 24 or 48 hr at 37°C in the presence and absence of 100 μM WGN. Calcium overload was induced by 2 μM ionomycin, hyperosmotic shock with excessive sucrose, oxidative stress by 2-phenethyl isothiocyanate (PEITC), and metabolic deprivation by exclusion of glucose. Hemolysis was estimated from extracellular hemoglobin, phosphatidylserine (PS) exposure by Annexin V-FITC, intracellular calcium by Fluo4/AM, and oxidative stress by 2',7'-dichlorodihydrofluorescein diacetate (H₂ DCFDA). While WGN did not rescue the cells from the hemolytic activity of ionomycin, it reduced PS externalization by interfering with calcium influx under both ionomycin treatment and metabolic exhaustion. WGN also significantly inhibited PS exposure upon hyperosmotic shock, but the effect was independent of calcium entry. Moreover, WGN exhibited antihemolytic and anti-eryptotic activities against PEITC without appreciable reduction in ROS levels. Altogether, WGN prevents PEITC-induced hemolysis and suppresses eryptosis due to calcium accumulation, hyperosmotic shock, oxidative stress, and metabolic exhaustion. These novel insights may open new avenues into the therapeutic application of WGN for conditions in which anemia is commonly encountered, most notably cancer. PRACTICAL APPLICATIONS: The herbal supplement Sho-Saiko-To (Xiaochaihu-tang) is commonly prescribed to relieve symptoms of liver disease. Flavonoids from the herbal constituents of Sho-Saiko-To have demonstrated considerable anti-inflammatory, antioxidant, antimicrobial, antitumor, and immunomodulatory properties. In this work, we identify WGN, a major flavonoid in Sho-Saiko-To, as a novel inhibitor of hemolysis and eryptosis of human erythrocytes. Since inordinate erythrocyte death is a major obstacle in therapeutic drug development, our findings argue for the use of WGN as a natural alternative, either as a primary or an adjuvant drug, for a wide assortment of pathological conditions including cancer.

Wogonin inhibits the growth of HT144 melanoma via regulating hedgehog signaling-mediated inflammation and glycolysis

Hedgehog (Hh) signaling has been proved to be closely associated with the occurrence of melanoma. Wogonin is one of the active components of flavonoids that extracts from Scutellariae radix. Previous studies showed that wogonin could inhibit the invasion and migration of B16F10 cells, and suppress the synthesis of melanin in A375 melanoma cells. However, the regulatory effects of Hh signaling in wogonin against melanoma and its potential mechanisms remain largely unknown. The present study aimed to investigate the effect of wogonin on the growth of HT144 melanoma, and to elucidate the role of Hh signaling in wogonin-induced antitumor effects by focusing on inflammation and glycolysis regulation. Wogonin inhibited the proliferation, colony formation and tumor growth of HT144 melanoma cells. Wogonin showed strong anti-inflammatory effect in HT144 melanoma, as shown by the decreased levels of pro-inflammatory factors, the increased level of anti-inflammatory factor and the decreased expression of inflammatory cytokines. Wogonin decreased the glucose consumption and the production of lactic acid and ATP, and decreased the activities of hexokinase (HK), phosphofructokinase(PFK) and pyruvate kinase (PK), and further inhibited the expression of monocarboxylate transporter 1 (MCT-1), MCT-4 and glucosecotransporter-1 (GLUT1), showing potent anti-glycolysis effect against HT144 melanoma. Wogonin inhibited the patched and Smo expression while increased Hhip expression in HT144 cells, suggesting that wogonin blocked the Hh signaling in HT144 cells. The Hh signaling inhibitor cyclopamine, like wogonin, inhibited the colony formation of HT144 cells, however, the inhibitory effect of wogonin on colony formation of HT144 cells was abrogated by the Hh signaling agonist SAG. In addition, SAG abrogated the inhibitory effect of wogonin on the secretion of inflammatory factors and the expression of inflammatory cytokines. Furthermore, SAG abrogated the inhibitory effect of wogonin on several key molecules controlling glycolysis. Overall, these findings suggested that the anti-tumor effect of wogonin can be attributed to the inhibition of Hh signaling-mediated regulation of inflammation and glycolysis in HT144 melanoma.

Flavonoid GL-V9 suppresses invasion and migration of human colorectal cancer cells by inhibiting PI3K/Akt and MMP-2/9 signaling

Tumor distant metastasis is the primary cause of death in colorectal cancer (CRC) patients. GL-V9 is a newly synthesized flavonoid derivative with several beneficial biological functions including anti-tumor and anti-inflammation. However, the anti-metastatic effect of GL-V9 and related mechanisms in CRC remains unknown. In this study, the anti-invasive and anti-migratory activities of GL-V9 were investigated in CRC cells. Using MTT assay, cell wound healing assay, and transwell migration assay, we showed that GL-V9 suppressed CRC cell viability, migration, and invasion in a concentration-dependent manner. In addition, the protein expression levels as well as activities of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) were significantly reduced after GL-V9 treatment. Further analysis of the underlying mechanism revealed that GL-V9 inhibited PI3K/Akt signaling pathway upstream of MMP-2 and MMP-9. In conclusion, our study demonstrated that GL-V9 could suppress CRC cell invasion and migration through PI3K/Ak and MMP-2/9 axis. Therefore, GL-V9 might be a potential novel therapeutic agent against CRC metastasis.

Fascinating Chemopreventive Story of Wogonin: A Chance to Hit on the Head in Cancer Treatment

Cancer, global havoc, is a group of debilitating diseases that strikes family as well as society. Cancer cases are drastically increasing these days. Despite many therapies and surgical procedures available, cancer is still difficult to control due to limited effective therapies or targeted therapies. Natural products can produce lesser side effects to the normal cells, which are the major demerit of chemotherapies and radiation. Wogonin, a natural product extracted from the plant, Scutellaria baicalensis has been widely studied and found with a high caliber to tackle most of the cancers via several mechanisms that include intrinsic as well as extrinsic apoptosis signaling pathways, carcinogenesis diminution, telomerase activity inhibition, metastasis inhibition in the inflammatory microenvironment, anti-angiogenesis, cell growth inhibition and arrest of the cell cycle, increased generation of H₂O₂ and accumulation of Ca²⁺ and also as an adjuvant along with anticancer drugs. This article discusses the role of wogonin in various cancers, its synergism with various drugs, and the mechanism by which wogonin controls tumor growth.

Growth Hormone Upregulates Mediators of Melanoma Drug Efflux and Epithelial-to-Mesenchymal Transition In Vitro and In Vivo

Simple Summary

Growth hormone (GH) action is strongly implicated in the progression and therapy resistance in several types of solid tumors which overexpress the GH receptor (GHR). The aim of our study was to characterize the effects of GH and its downstream effector insulin-like growth factor 1 (IGF-1) on melanoma using in vitro and in vivo models. We confirmed an IGF-1-independent role of elevated circulating GH in upregulating key mechanisms of therapy resistance and malignancy with analyses conducted at the molecular and cellular level. We identified that GH upregulates key mechanisms of therapy resistance and metastases in melanoma tumors in an IGF-1 dependent and independent manner by upregulating multidrug efflux pumps and EMT transcription factors. Our study reveals that GH action renders an intrinsic drug resistance phenotype to the melanoma tumors—a clinically crucial property of GH verifiable in other human cancers with GHR expression.

Abstract

Growth hormone (GH) and the GH receptor (GHR) are expressed in a wide range of malignant tumors including melanoma. However, the effect of GH/insulin-like growth factor (IGF) on melanoma in vivo has not yet been elucidated. Here we assessed the physical and molecular effects of GH on mouse melanoma B16-F10 and human melanoma SK-MEL-30 cells in vitro. We then corroborated these observations with syngeneic B16-F10 tumors in two mouse lines with different levels of GH/IGF: bovine GH transgenic mice (bGH; high GH, high IGF-1) and GHR gene-disrupted or knockout mice (GHRKO; high GH, low IGF-1). In vitro, GH treatment enhanced mouse and human melanoma cell growth, drug retention and cell invasion. While the in vivo tumor size was unaffected in both bGH and GHRKO mouse lines, multiple drug-efflux pumps were up regulated. This intrinsic capacity of therapy resistance appears to be GH dependent. Additionally, epithelial-to-mesenchymal transition (EMT) gene transcription markers were significantly upregulated in vivo supporting our current and recent in vitro observations. These syngeneic mouse melanoma models of differential GH/IGF action can be valuable tools in screening for therapeutic options where lowering GH/IGF-1 action is important.

Wogonoside Attenuates Cutaneous Squamous Cell Carcinoma by Reducing Epithelial-Mesenchymal Transition/Invasion and Cancer Stem-Like Cell Property

Purpose

Cutaneous squamous cell carcinoma (cSCC) is the most common second basal cell carcinoma in our population. Wogonoside, the main in vivo metabolite of wogonin, possesses anti-inflammatory, anti-angiogenesis and anti-cancer activities. Nevertheless, the effectiveness of wogonoside therapy on cSCC has not been clarified.

Methods

In this study, we investigated the effects of wogonoside on cell proliferation, invasion, epithelial–mesenchymal transition (EMT) and cancer stem-like cell (CSC) properties of SCL-1 and SCC12 cell lines, and the effects on tumor formation in vivo. In vitro, cells were treated with 0, 25, 50 and 100 μM wogonoside for 48 h. In vivo, SCL-1 cells were subcutaneously injected into the right thigh of mice to form xenograft tumors. Animals were randomly divided into two groups (n=10): the control group and the 80 mg/kg wogonoside group.

Results

The results showed that wogonoside attenuated proliferation, invasion and EMT of SCL-1 and SCC12 cell lines, and enhanced the rate of apoptosis. Meanwhile, wogonoside efficiently abolished the CSC traits of cSCC; the expression of CSC markers (ALDH1, SOX-2, Oct4 and CD44) and the percentage of CD133⁺ cells were remarkably downregulated. In addition, we found that wogonoside repressed the activation of both PI3K/AKT and Wnt/β-catenin pathways. In vivo, wogonoside significantly inhibited tumor formation.

Conclusion

The results indicated that wogonoside could attenuate cSCC by reducing EMT, invasion and CSC properties. The efficacy of intervention may be related to inhibition of the PI3K/Akt and Wnt/β-catenin pathways. These novel findings could furnish new ideas on the potential therapeutic application of wogonoside in cSCC cancellation and cancer intervention.

MYH9 suppresses melanoma tumorigenesis, metastasis and regulates tumor microenvironment

Non-muscle myosin IIA heavy chain (MYH9) has been implicated in many physiological and pathological functions including cell adhesion, polarity, motility to cancer. However, its role in melanoma remains unexplored. The aim of our study was to evaluate the role of MYH9 in melanoma tumor development and metastasis and further to find out the potential underlying mechanisms. In this study, we evaluated the in vitro migratory and invasive properties and in vivo tumor development and metastasis in C57BL/6 mice by silencing MYH9 in B16F10 melanoma cells. Knocking down MYH9 enhanced migration and invasiveness of B16F10 cells in vitro. Furthermore, MYH9 silencing accelerated tumor growth and metastasis in melanoma subcutaneous and intravenous mouse models. Next, oncogenes analysis revealed epithelial-mesenchymal transition and Erk signaling pathway are being regulated with MYH9 expression. Finally, MYH9 silencing in B16F10 cells modulates the tumor microenvironment by manipulating the leukocytes and macrophages infiltration in tumors. These findings established the opposing role of MYH9 as a tumor suppressor in melanoma suggesting specific MYH9 based approaches in therapeutics.

Perfusion and Inflation of the Mouse Lung for Tumor Histology

The ability to evaluate lung histology is critical for the fields of lung cancer research and cancer metastasis. It is equally important to perform necropsies rapidly and efficiently from studies without sacrificing the quality of the tissues procured. The goal of this protocol is to present a method to rapidly perfuse, inflate, and fix mouse lungs for downstream histological analysis. This method does not standardize lung inflation; thus, it does not require any special procedures or equipment and instead simply instills fixative directly through the trachea following perfusion through the heart. This allows for sufficient estimation of tumor size, histology, and scoring. This also allows for the collection of frozen tissue prior to lung tissue fixation. This method is limited in that it does not allow for later morphometric quantification of the lung; however, it is more than sufficient for lung tumor analysis from genetically engineered mouse models (GEMMs), syngeneic models, as well as xenograft tumor and metastasis studies.

Naturally occurring anti-cancer compounds: shining from Chinese herbal medicine

Numerous natural products originated from Chinese herbal medicine exhibit anti-cancer activities, including anti-proliferative, pro-apoptotic, anti-metastatic, anti-angiogenic effects, as well as regulate autophagy, reverse multidrug resistance, balance immunity, and enhance chemotherapy in vitro and in vivo. To provide new insights into the critical path ahead, we systemically reviewed the most recent advances (reported since 2011) on the key compounds with anti-cancer effects derived from Chinese herbal medicine (curcumin, epigallocatechin gallate, berberine, artemisinin, ginsenoside Rg3, ursolic acid, silibinin, emodin, triptolide, cucurbitacin B, tanshinone I, oridonin, shikonin, gambogic acid, artesunate, wogonin, β-elemene, and cepharanthine) in scientific databases (PubMed, Web of Science, Medline, Scopus, and Clinical Trials). With a broader perspective, we focused on their recently discovered and/or investigated pharmacological effects, novel mechanism of action, relevant clinical studies, and their innovative applications in combined therapy and immunomodulation. In addition, the present review has extended to describe other promising compounds including dihydroartemisinin, ginsenoside Rh2, compound K, cucurbitacins D, E, I, tanshinone IIA and cryptotanshinone in view of their potentials in cancer therapy. Up to now, the evidence about the immunomodulatory effects and clinical trials of natural anti-cancer compounds from Chinese herbal medicine is very limited, and further research is needed to monitor their immunoregulatory effects and explore their mechanisms of action as modulators of immune checkpoints.

Combination therapy with dacarbazine and statins improved the survival rate in mice with metastatic melanoma

Malignant melanoma is a highly aggressive skin cancer, and the overall median survival in patients with metastatic melanoma is only 6-9 months. Although molecular targeted therapies have recently been developed and have improved the overall survival, melanoma patients may show no response and acquisition of resistance to these drugs. Thus, other molecular approaches are essential for the treatment of metastatic melanoma. In the present study, we investigated the effect of cotreatment with dacarbazine and statins on tumor growth, metastasis, and survival rate in mice with metastatic melanomas. We found that cotreatment with dacarbazine and statins significantly inhibited tumor growth and metastasis via suppression of the RhoA/RhoC/LIM domain kinase/serum response factor/c-Fos pathway and enhanced p53, p21, p27, cleaved caspase-3, and cleaved poly(ADP-ribose) polymerase 1 expression in vivo. Moreover, the cotreatment significantly improved the survival rate in metastasis-bearing mice. Importantly, treatment with dacarbazine plus 100 mg/kg simvastatin or fluvastatin prevented metastasis-associated death in 4/20 mice that received dacarbazine + simvastatin and in 8/20 mice that received dacarbazine + fluvastatin (survival rates, 20% and 40%, respectively). These results suggested that cotreatment with dacarbazine and statins may thus serve as a new therapeutic approach to control tumor growth and metastasis in melanoma patients.

Anticancer effect of nor-wogonin (5, 7, 8-trihydroxyflavone) on human triple-negative breast cancer cells via downregulation of TAK1, NF-κB, and STAT3

BACKGROUND

Nor-wogonin, a polyhydroxy flavone, has been shown to possess antitumor activity. However, the mechanisms responsible for its antitumor activity are poorly studied. Herein, we investigated the mechanisms of nor-wogonin actions in triple-negative breast cancer (TNBC) cells.

METHODS

Effects of nor-wogonin on cell proliferation and viability of four TNBC cell lines (MDA-MB-231, BT-549, HCC70, and HCC1806) and two non-tumorigenic breast cell lines (MCF-10A and AG11132) were assessed by BrdU incorporation assays and trypan blue dye exclusion tests. Cell cycle and apoptosis analyses were carried out by flow cytometry. Protein expression was analyzed by immunoblotting.

RESULTS

Nor-wogonin significantly inhibited the growth and decreased the viability of TNBC cells; however, it exhibited no or minimal effects in non-tumorigenic breast cells. Nor-wogonin (40 μM) was a more potent anti-proliferative and cytotoxic agent than wogonin (100 μM) and wogonoside (100 μM), which are structurally related to nor-wogonin. The antitumor effects of nor-wogonin can be attributed to cell cycle arrest via reduction of the expression of cyclin D1, cyclin B1, and CDK1. Furthermore, nor-wogonin induced mitochondrial apoptosis, (as evidenced by the increase in % of cells that are apoptotic), decreases in the mitochondrial membrane potential (ΔΨm), increases in Bax/Bcl-2 ratio, and caspase-3 cleavage. Moreover, nor-wogonin attenuated the expression of the nuclear factor kappa-B and activation of signal transducer and activator of transcription 3 pathways, which can be correlated with suppression of transforming growth factor-β-activated kinase 1 in TNBC cells.

CONCLUSION

These results showed that nor-wogonin might be a potential multi-target agent for TNBC treatment.

The Cytotoxic and Antimigratory Activity of Brazilin-Doxorubicin on MCF-7/HER2 Cells

Purpose: Breast cancer cells with overexpression of HER2 are known to be more aggressive, invasive, and resistant to chemotherapeutic agent. Brazilin, the major compound in the Caesalpinia sappan L. (CS) heartwood, has been studied for it's anticancer activity. The purpose of this study was to investigate the cytotoxic and antimigratory activity of brazilin (Bi) in combination with doxorubicin (Dox) on MCF-7/HER2 cells.

Methods: Cytotoxic activities of Bi individually and in combination with Dox were examined by MTT assay. Synergistic effects were analyzed by combination index (CI). Apoptosis and cell cycle profiles were observed by using flow cytometry. Migrating and invading cells were observed by using a Boyden chamber assay. Levels of MMP2 and MMP9 activity were observed by using a gelatin zymography assay. Levels of HER2, Bcl-2, Rac1, and p120 protein expression were observed by using an immunoblotting assay.

Results: The results of the MTT assay showed that Bi inhibited MCF-7/HER2 cell growth in a dose-dependent manner with an IC50 of 54 ± 3.7 µM. Furthermore, the combination of Bi and Dox showed a synergistic effect (CI <1). Flow cytometric analysis of Bi and its combination with Dox showed cellular accumulation in the G2/M phase and induction of apoptosis through suppression of Bcl-2 protein expression. In the Boyden chamber assay, gelatin zymography, and subsequent immunoblotting assay, the combination Bi and Dox inhibited migration, possibly through downregulation of MMP9, MMP2, HER2, Rac1, and p120 protein expression.

Conclusion: We conclude that Bi enhanced cytotoxic activity of Dox and inhibited migration of MCF-7/HER2 cells. Therefore, we believe that it has strong potential to be developed for the treatment of metastatic breast cancer with HER2 overexpression.

Wogonin suppresses the LPS‑enhanced invasiveness of MDA‑MB‑231 breast cancer cells by inhibiting the 5‑LO/BLT2 cascade

Wogonin, a naturally occurring bioactive monoflavonoid isolated from Scutellariae radix (roots of Scutellariae baicalensis Georgi), has known anticancer effects. However, the molecular signaling mechanism by which wogonin inhibits invasiveness in breast cancer cells remains unclear. In the present study, it was observed that wogonin exerted an inhibitory effect on the lipopolysaccha-ride (LPS)-enhanced invasiveness of MDA-MB-231 cells. In addition, wogonin inhibited the synthesis of interleukin-8 (IL-8) and matrix metallopeptidase-9 (MMP-9), which are critical for promoting invasiveness in MDA-MB-231 cells. Wogonin also suppressed the expression of leukot-riene B4 receptor 2 (BLT2) and the synthesis of its ligand, by inhibiting 5-lipoxygenase (5-LO) in LPS-stimulated MDA-MB-231 cells. Notably, wogonin attenuated the production of IL-8 and MMP-9 by inhibiting the BLT2/extracellular signal-regulated kinase (ERK)-linked cascade. Finally, in vivo, LPS-driven MDA-MB-231 cell metastasis was markedly suppressed by wogonin administration. Overall, the present results suggested that wogonin inhibited the 5-LO/BLT2/ERK/IL-8/MMP-9 signaling cascade and demonstrated that this cascade may be an important target through which wogonin exerts its anticancer effects in breast cancer.

BM microenvironmental protection of CML cells from imatinib through Stat5/NF-κB signaling and reversal by Wogonin

Constitutive Stat5 activation enhanced cell survival and resistance to imatinib (IM) in chronic myelogenous leukemia (CML) cells. However, the mechanism of Stat5 activation in mediating resistance to IM in bone marrow (BM) microenvironment has not been evaluated precisely. In this study, we reported HS-5-derived conditioned medium (CM) significantly enhanced IM resistance in K562 and KU812. Interestingly, upregulation of the proportion of CD34+ subpopulation was found in CML cells. Subsequently, the BCR/ABL-independent activation of Stat5 increased P-glycoprotein (P-gp) activity in CM-mediated protection of CML stem cells (LSCs) from IM. Further research revealed Stat5 activation increased the DNA binding activity of NF-κB though binding of p-Stat5 and p-RelA in nucleus. Moreover, highly acetylated RelA was required for Stat5-mediated RelA nuclear binding. The study further confirmed that Wogonin potentiated the inhibitory effects of IM on leukemia development by suppressing Stat5 pathway both in CM model and the K562 xenograft model. In summary, results clearly demonstrated BCR/ABL-independent Stat5 survival pathway could contribute to resistance of CML LSCs to IM in BM microenvironment and suggested that natural durgs effectively inhibiting Stat5 may be an attractive approach to overcome resistance to BCR/ABL kinase inhibitors.

Wogonoside inhibits invasion and migration through suppressing TRAF2/4 expression in breast cancer

Background

Twist1 is involved in tumor initiation and progression, which especially contributes to tumor invasion and metastasis. Wogonoside is the main in-vivo metabolite of wogonin, and it is also a natural product with potential treatment effects against cancer.

Methods

In this study, we investigated the in-vitro anti-invasion and in-vivo anti-metastasis effects of wogonoside on breast cancer cells and uncovered its underlying mechanism.

Results

The results showed that wogonoside could suppress the growth and metastasis of breast tumor in the orthotopic model of MDA-MB-231 cells. We found that wogonoside could reduce the overexpression of TNF-α, TRAF2 and TRAF4 in later stage of tumor, and improved tumor microenvironment. Therefore, TNF-α was utilized to induce metastases of breast cancer cell in vitro. Wogonoside could inhibit invasion and migration in TNF-α-induced MDA-MB-231, MDA-MB-435, and BT-474 cells. Mechanically, wogonoside inactivated NF-κB signaling through decreasing the protein expression of TRAF2/4, which further inhibited Twist1 expression. Consequently, wogonoside could down-regulate MMP-9, MMP-2, vimentin and CD44v6 expression in TNF-α-induced MDA-MB-231 and MDA-MB-435 cells. Then, these findings were proved in TNF-α + TGF-β1-induced MCF7 cells.

Conclusions

Wogonoside might be a potential therapeutic agent for the treatment of tumor metastasis in breast cancer.

Wogonin suppresses stem cell-like traits of CD133 positive osteosarcoma cell via inhibiting matrix metallopeptidase-9 expression

Background

Several efforts have been deployed to cure osteosarcoma, a high-grade malignant bone tumour in children and adolescents. However, some challenges such as drug resistance, relapse, and tumour metastasis remain owing to the existence of cancer stem cells (CSC). There is an urgent need to develop cost-effective and safe therapies.

Methods

Wogonin, an extract from the root of Scutellaria baicalensis, has long been considered as a promising natural and safe compound for anti-tumourigenesis, particularly to inhibit tumour invasion and metastasis. Hoechst 33,342 staining, wound healing assay, sphere formation assay, western blotting, and gelatin zymography assays were performed in CD133 positive osteosarcoma cell.

Results

In this study, we examined the effect of Wogonin on the mobility of human osteosarcoma CSC. Wogonin induces apoptosis of human osteosarcoma CSC, inhibits its mobility in vitro via downregulation of MMP-9 expression, and represses its renewal ability.

Conclusions

We demonstrated that Wogonin decreases the renewal capacity of CSC. By inhibiting the formation of and reducing the size of spheres, Wogonin at a concentration of 40–80 μM effectively minimizes potential risk from CSC. Taken together, we have demonstrated a new approach for developing a potential therapy for osteosarcoma.

Anti-tumor activity of wogonin, an extract from Scutellaria baicalensis, through regulating different signaling pathways

Wogonin is a plant flavonoid compound extracted from Scutellaria baicalensis (Huang-Qin or Chinese skullcap) and has been studied thoroughly by many researchers till date for its anti-viral, anti-oxidant, anti-cancerous and neuro-protective properties. Numerous experiments conducted in vitro and in vivo have demonstrated wogonin's excellent tumor inhibitory properties. The anti-cancer mechanism of wogonin has been ascribed to modulation of various cell signaling pathways, including serine-threonine kinase Akt (also known as protein kinase B) and AMP-activated protein kinase (AMPK) pathways, p53-dependent/independent apoptosis, and inhibition of telomerase activity. Furthermore, wogonin also decreases DNA adduct formation with a carcinogenic compound 2-Aminofluorene and inhibits growth of drug resistant malignant cells and their migration and metastasis, without any side effects. Recently, newly synthesized wogonin derivatives have been developed with impressive anti-tumor activity. This review is the succinct appraisal of the pertinent articles on the mechanisms of anti-tumor properties of wogonin. We also summarize the potential of wogonin and its derivatives used alone or as an adjunct therapy for cancer treatment. Furthermore, pharmacokinetics and side effects of wogonin and its analogues have also been discussed.

Apoptotic Mechanism of Human Leukemia K562/A02 Cells Induced by Magnetic Ferroferric Oxide Nanoparticles Loaded with Wogonin

Background:

Traditional Chinese medicine wogonin plays an important role in the treatment of leukemia. Recently, the application of drug-coated magnetic nanoparticles (MNPs) to increase water solubility of the drug and to enhance its chemotherapeutic efficiency has attracted much attention. Drugs coated with MNPs are becoming a promising way for better leukemia treatment. This study aimed to assess the possible molecular mechanisms of wogonin-coated MNP-Fe₃O₄ (Wog-MNPs-Fe₃O₄) as an antileukemia agent.

Methods:

After incubated for 48 h, the antiproliferative effects of MNPs, wogonin, or Wog-MNPs-Fe₃O₄ on K562/A02 cells were determined by methyl thiazolyl tetrazolium (MTT) assay. The apoptotic rates of K562/A02 cells treated with either wogonin or Wog-MNPs-Fe₃O₄ were determined by flow cytometer (FCM) assay. The cell cycle arrest in K562/A02 cells was determined by FCM assay. The elementary molecular mechanisms of these phenomena were explored by Western blot and reverse transcriptase polymerase chain reaction (RT-PCR).

Results:

With cell viabilities ranging from 98.76% to 101.43%, MNP-Fe₃O₄ was nontoxic to the cell line. Meanwhile, the wogonin and Wog-MNPs-Fe₃O₄ had little effects on normal human embryonic lung fibroblast cells. The cell viabilities of the Wog-MNPs-Fe₃O₄ group (28.64–68.36%) were significantly lower than those of the wogonin group (35.53–97.28%) in a dose-dependent manner in 48 h (P < 0.001). The apoptotic rate of K562/A02 cells was significantly improved in 50 μmol/L Wog-MNPs-Fe₃O₄ group (34.28%) compared with that in 50 μmol/L wogonin group (23.46%; P < 0.001). Compared with those of the 25 and 50 μmol/L wogonin groups, the ratios of G0/G1-phase K562/A02 cells were significantly higher in the 25 and 50 μmol/L Wog-MNPs-Fe₃O₄ groups (all P < 0.001). The mRNA and protein expression levels of the p21 and p27 in the K562/A02 cells were also significantly higher in the Wog-MNPs-Fe₃O₄ group compared with those of the wogonin group (all P < 0.001).

Conclusions:

This study demonstrated that MNPs were the effective drug delivery vehicles to deliver wogonin to the leukemia cells. Through increasing cells arrested at G0/G1-phase and inducing apoptosis of K562/A02 cells, MNPs could enhance the therapeutic effects of wogonin on leukemia cells. These findings indicated that MNPs loaded with wogonin could provide a promising way for better leukemia treatment.

Bifunctional effects of O-methylated flavones from Scutellaria baicalensis Georgi on melanocytes: Inhibition of melanin production and intracellular melanosome transport

The growing interest in skin lightening has recently renewed attention on the esthetic applications of Chinese herbal medicine. Although Scutellaria baicalensis Georgi is used for antipyretic and antiinflammatory purposes, its whitening effect remains unclear. This study reports three major findings: (1) S. baicalensis has a potent inhibitory effect on melanogenesis; (2) wogonin and its glycoside are the active components of S. baicalensis; and (3) O-methylated flavones from S. baicalensis, such as wogonin, inhibit intracellular melanosome transport. Using a melanin quantification assay, we showed that S. baicalensis potently inhibits melanogenesis in B16F10 cells. Componential analyses revealed that the main components of S. baicalensis are baicalin, wogonoside, baicalein, wogonin, and oroxylin A. Among these five flavones, wogonin and wogonoside consistently inhibited melanogenesis in both B16F10 melanoma cells and primary melanocytes. Wogonin exhibited the strongest inhibition of melanin production and markedly lightened the color of skin equivalents. We identified microphthalmia-associated transcription factor and tyrosinase-related proteins as potential targets of wogonin- and wogonoside-induced melanogenesis suppression. In culture, we found that the melanosomes in wogonin-treated B16F10 cells were localized to the perinuclear region. Immunoblotting analyses revealed that wogonin significantly reduced in melanophilin protein, which is required for actin-based melanosome transport. Other actin-based melanosome transport-related molecules, i.e., Rab27A and myosin Va, were not affected by wogonin. Cotreatment with MG132 blocked the wogonin-induced decrease in melanophilin, suggesting that wogonin promotes the proteolytic degradation of melanophilin via the calpain/proteasomal pathway. We determined that the structural specificities of the mono-O-methyl group in the flavone A-ring and the aglycone form were responsible for reducing melanosome transport. Furthermore, wogonin and two wogonin analogs, mono-O-methyl flavones, strongly suppressed melanosome transport. Our findings suggest the applicability of S. baicalensis in the esthetic field. Thus, we propose a novel pharmacologic approach for the treatment of hyperpigmentation.

The inhibitory effect of 7,7″-dimethoxyagastisflavone on the metastasis of melanoma cells via the suppression of F-actin polymerization

7,7″-Dimethoxyagastisflavone (DMGF), a biflavonoid isolated from Taxus × media cv. Hicksii, induces apoptotic and autophagic cell death. However, whether DMGF suppresses tumor metastasis is unclear. The aim of this study was to investigate the anti-metastatic activities of DMGF on the metastatic processes of melanoma cells in vivo and in vitro. A transwell assay showed that DMGF could effectively attenuate the motility of B16F10 cells, and the results of real-time PCR revealed that DMGF also suppressed the expressions of matrix metalloproteinase-2 (MMP-2). Moreover, DMGF did not influence tube formation but inhibited the migration of endothelial cells. Furthermore, animal models were used to monitor the effects of DMGF on tumor metastasis, and all models showed that DMGF significantly suppressed the metastatic behaviors of B16F10 cells, including intravasation, colonization, and invasion of the lymphatic duct. In addition, DMGF could also reduce the densities of the blood vessels in the tumor area in vivo. Further investigation of the molecular mechanisms of anti-metastatic activity revealed that DMGF can down-regulate the levels of key modulators of the Cdc42/Rac1 pathway to interfere in F-actin polymerization and suppress the formation of lamellipodia by reducing the phosphorylation of CREB. These data suggested that DMGF presents anti-metastatic activities in B16F10 melanoma cells. Here, we demonstrated that DMGF can inhibit the metastasis of highly invasive melanoma cancer cells through the down-regulation of F-actin polymerization. Considering these findings, DMGF may be further developed to serve as a chemoprevention drug for patients with metastatic melanoma.

Advances of wogonin, an extract from Scutellaria baicalensis, for the treatment of multiple tumors

As the major bioactive compound of Scutellaria baicalensis that has been approved to be effective as an anti-inflammatory and antiviral inhibitor in cardiovascular diseases, wogonin (WG) showed potent and promising antitumor effects both in vitro and in vivo. It has been proved that WG has the ability to inhibit the growth of tumor cells, induce apoptosis, and suppress angiogenesis. The molecular mechanisms involve reactive oxygen species, Ca²⁺, NF-κB, tumor necrosis factor-related apoptosis-inducing ligand, and tumor necrosis factor-alpha. Furthermore, the synergistic effect of WG with 5-fluorouracil, etoposide, and adriamycin to enhance chemotherapy and reverse drug resistance has also been confirmed. In this review, we summarize the advances in recent years on the antitumor effect of WG on multiple tumors; in addition, we also present information regarding the synergistic and chemosensitizing effects of WG with other drugs to illustrate its potential use in the clinic.

Reduction of metastatic and angiogenic potency of malignant cancer by Eupatorium fortunei via suppression of MMP-9 activity and VEGF production

Eupatorium fortunei has long been used to treat nausea and poor appetite, and has been prescribed as a diuretic and detoxifying drug in Chinese medicine. Recent studies have demonstrated that E. fortunei possesses anti-bacterial, anti-oxidant, and anti-diabetic activities, as well as cytotoxicity to human leukemia cells. However, at non-toxic concentrations, the effects of an aqueous extract of E. fortunei (WEF) on the metastatic and angiogenic potential of malignant tumor cells have not been reported. In this study, we found that WEF suppressed the metastatic properties, including anchorage-independent colony formation, migration, and invasion, by downregulating the proteolytic activity of MMP-9. NF-κB activation and the phosphorylation of p38 and JNK were reduced significantly by WEF. Additionally, WEF inhibited tumor-induced angiogenesis markedly, affecting HUVEC migration, tube formation by HUVECs, and microvessel sprouting from rat aortic rings via a reduction in VEGF in tumors. In a pulmonary metastasis model, daily administration of WEF at 50 mg/kg markedly decreased metastatic colonies of intravenously injected B16F10 cells on the lung surface in C57BL/6J mice. Further, none of the WEF-administered mice exhibited systemic toxicity. Taken together, our results indicate that WEF is a potential therapeutic herbal product that may be useful for controlling malignant metastatic cancer.