Geraniin inhibits TGF-β1-induced epithelial-mesenchymal transition and suppresses A549 lung cancer migration, invasion and anoikis resistance

Geraniin: A dietary ellagitannin as a modulator of signalling pathways in cancer progression

Cancer remains a global health challenge, necessitating the exploration of novel therapeutic agents. Current treatment options are unable to overwhelm and cure the cancer burden. Hence, identifying new bioactive molecular entities with potent anticancer activity is the need of the hour. Ellagitannin Geraniin (GN) is one such evidence-based novel bioactive molecular entity (BME) available from different natural sources that can effectively combat cancer. This narrative review attempts to investigate the potential of BME-GN from 2005 to 2023 as an efficient molecular anti-cancer therapeutic against diverse cancers. We provide information on GN's pharmacological advantages, metabolite profile, and capacity to modulate multiple molecular targets involved in the hallmarks of cancer. Using the search terms "Geraniin," "Gallic acid," "Ellagitannin," "pharmacological properties," "health," "antioxidant," "apoptosis," "disease management," "anti-proliferative," "in vitro," "anti-inflammatory," "anti-angiogenic," "in vivo," and "clinical trials," We searched the scientific literature using Scopus, Web of Science, Google Scholar, and PubMed. We removed publications that included overlap or equivalent content and used the most recent review on each issue as our primary reference. From an initial pool of 430 articles, 52 studies met the search criteria. These studies collectively provide substantial in vitro, in vivo, and clinical evidence of GN's potential to combat diverse cancers. Mechanistic insights revealed its involvement in fostering apoptosis, anti-inflammatory, and modulation of key signalling pathways implicated in the hallmarks of cancer. GN's pleiotropic pharmacological and molecular therapeutic properties strongly suggest its potential as a promising anticancer agent.

Targeting anoikis resistance as a strategy for cancer therapy

Anoikis, known as matrix detachment-induced apoptosis or detachment-induced cell death, is crucial for tissue development and homeostasis. Cancer cells develop means to evade anoikis, e.g. anoikis resistance, thereby allowing for cells to survive under anchorage-independent conditions. Uncovering the mechanisms of anoikis resistance will provide details about cancer metastasis, and potential strategies against cancer cell dissemination and metastasis. Here, we summarize the principal elements and core molecular mechanisms of anoikis and anoikis resistance. We discuss the latest progress of how anoikis and anoikis resistance are regulated in cancers. Furthermore, we summarize emerging data on selective compounds and nanomedicines, explaining how inhibiting anoikis resistance can serve as a meaningful treatment modality against cancers. Finally, we discuss the key limitations of this therapeutic paradigm and possible strategies to overcome them. In this review, we suggest that pharmacological modulation of anoikis and anoikis resistance by bioactive compounds could surmount anoikis resistance, highlighting a promising therapeutic regimen that could be used to overcome anoikis resistance in cancers.

Geraniin Alleviates Inflammation in Caco-2 Cells and Dextran Sulfate Sodium-Induced Colitis Mice by Targeting IL-1β

IL-1β is an important cytokine implicated in the progression of inflammatory bowel disease (IBD) and intestinal barrier dysfunction. The polyphenolic compound, geraniin, possesses bioactive properties, such as antitumor, antioxidant, anti-inflammatory, antihypertensive, and antiviral activities; however, its IL-1β-targeted anticolitis activity remains unclear. Here, we evaluated the inhibitory effect of geraniin in IL-1β-stimulated Caco-2 cells and a dextran sulfate sodium (DSS)-induced colitis mouse model. Geraniin blocked the interaction between IL-1β and IL-1R by directly binding to IL-1β and inhibited the IL-1β activity. It suppressed IL-1β-induced intestinal tight junction damage in human Caco-2 cells by inhibiting IL-1β-mediated MAPK, NF-kB, and MLC activation. Moreover, geraniin administration effectively reduced colitis symptoms and attenuated intestinal barrier injury in mice by suppressing elevated intestinal permeability and restoring tight junction protein expression through the inhibition of MAPK, NF-kB, and MLC activation. Thus, geraniin exhibits anti-IL-1β activity and anticolitis effect by hindering the IL-1β and IL-1R interaction and may be a promising therapeutic anti-IL-1β agent for IBD treatment.

Modulation of hypoxia-inducible factor-1 signaling pathways in cancer angiogenesis, invasion, and metastasis by natural compounds: a comprehensive and critical review

Tumor cells employ multiple signaling mediators to escape the hypoxic condition and trigger angiogenesis and metastasis. As a critical orchestrate of tumorigenic conditions, hypoxia-inducible factor-1 (HIF-1) is responsible for stimulating several target genes and dysregulated pathways in tumor invasion and migration. Therefore, targeting HIF-1 pathway and cross-talked mediators seems to be a novel strategy in cancer prevention and treatment. In recent decades, tremendous efforts have been made to develop multi-targeted therapies to modulate several dysregulated pathways in cancer angiogenesis, invasion, and metastasis. In this line, natural compounds have shown a bright future in combating angiogenic and metastatic conditions. Among the natural secondary metabolites, we have evaluated the critical potential of phenolic compounds, terpenes/terpenoids, alkaloids, sulfur compounds, marine- and microbe-derived agents in the attenuation of HIF-1, and interconnected pathways in fighting tumor-associated angiogenesis and invasion. This is the first comprehensive review on natural constituents as potential regulators of HIF-1 and interconnected pathways against cancer angiogenesis and metastasis. This review aims to reshape the previous strategies in cancer prevention and treatment.

Targeting the key players of phenotypic plasticity in cancer cells by phytochemicals

Plasticity of phenotypic traits refers to an organism's ability to change in response to environmental stimuli. As a result, the response may alter an organism's physiological state, morphology, behavior, and phenotype. Phenotypic plasticity in cancer cells describes the considerable ability of cancer cells to transform phenotypes through non-genetic molecular signaling activities that promote therapy evasion and tumor metastasis via amplifying cancer heterogeneity. As a result of metastable phenotypic state transitions, cancer cells can tolerate chemotherapy or develop transient adaptive resistance. Therefore, new findings have paved the road in identifying factors and agents that inhibit or suppress phenotypic plasticity. It has also investigated novel multitargeted agents that may promise new effective strategies in cancer treatment. Despite the efficiency of conventional chemotherapeutic agents, drug toxicity, development of resistance, and high-cost limit their use in cancer therapy. Recent research has shown that small molecules derived from natural sources are capable of suppressing cancer by focusing on the plasticity of phenotypic responses. This systematic, comprehensive, and critical review analyzes the current state of knowledge regarding the ability of phytocompounds to target phenotypic plasticity at both preclinical and clinical levels. Current challenges/pitfalls, limitations, and future perspectives are also discussed.

Securinega suffruticosa extract alleviates atopy-like lesions in NC/Nga mice via inhibition of the JAK1-STAT1/3 pathway

Securinega suffruticosa (SS) has well-known antioxidant, anti-vascular inflammation, and anti-bone resorption effects; however, the effects of SS in atopic dermatitis (AD) remain unknown. We examined the effects of SS on AD via application of Dermatophagoides farinae extract (DfE) to the ears and skin of NC/Nga mice. As a result of SS administration, DfE-induced AD mice had reduced ear thickness, epidermal thickness, scratching behavior, and transepidermal water loss. The serum levels of immunoglobulin E and thymic interstitial lymphopoietin (TSLP) were reduced by SS application. SS decreased mast cell and eosinophil recruitment to skin lesions. Phosphorylation of signal transducer and activation of transcription (STAT)1, STAT3, and Janus kinase 1 were reduced in the skin tissue of SS-administered mice, and downregulated filaggrin was restored. SS reduced the levels of interleukin-6, regulated on activation, normal T cell expressed and secreted chemokine, and TSLP in interferon-γ/tumor necrosis factor-α-induced keratinocytes. The main components of SS were rutin and geraniin. These study results indicated that SS extract attenuated AD and has potential as a therapeutic natural product candidate for AD.

Transforming Growth Factor Beta and Epithelial to Mesenchymal Transition Alter Homologous Recombination Repair Gene Expression and Sensitize BRCA Wild-Type Ovarian Cancer Cells to Olaparib

Epithelial ovarian cancer (EOC) remains the most lethal gynecologic malignancy, largely due to metastasis and drug resistant recurrences. Fifteen percent of ovarian tumors carry mutations in BRCA1 or BRCA2, rendering them vulnerable to treatment with PARP inhibitors such as olaparib. Recent studies have shown that TGFβ can induce "BRCAness" in BRCA wild-type cancer cells. Given that TGFβ is a known driver of epithelial to mesenchymal transition (EMT), and the connection between EMT and metastatic spread in EOC and other cancers, we asked if TGFβ and EMT alter the susceptibility of EOC to PARP inhibition. Epithelial EOC cells were transiently treated with soluble TGFβ, and their clonogenic potential, expression, and function of EMT and DNA repair genes, and response to PARP inhibitors compared with untreated controls. A second epithelial cell line was compared to its mesenchymal derivative for EMT and DNA repair gene expression and drug responses. We found that TGFβ and EMT resulted in the downregulation of genes responsible for homologous recombination (HR) and sensitized cells to olaparib. HR efficiency was reduced in a dose-dependent manner. Furthermore, mesenchymal cells displayed sensitivity to olaparib, cisplatin, and the DNA-PK inhibitor Nu-7441. Therefore, the treatment of disseminated, mesenchymal tumors may represent an opportunity to expand the clinical utility of PARP inhibitors and similar agents.

A Focused Review on Molecular Signalling Mechanisms of Ginsenosides Anti-Lung Cancer and Anti-inflammatory Activities

BACKGROUND

Ginseng (Panax ginseng Meyer) is a cultivated medicinal herb that has been widely available in the Asian region since the last century. Ginseng root is used worldwide in Oriental medicine. Currently, the global mortality and infection rates for lung cancer and inflammation are significantly increasing. Therefore, various preventative methods related to the activity of ginsenosides have been used for lung cancer as well as inflammation.

METHODS

Web-based searches were performed on Web of Science, Springer, PubMed, and Scopus. A cancer statistical analysis was also conducted to show the current ratio of affected cases and death from lung cancer around the world.

RESULTS

Ginsenosides regulate the enzymes that participate in tumor growth and migration, such as nuclear factor kappa B (NF-κB), mitogen-activated protein kinase (p38 MAPK), c-Jun N-terminal kinase (JNK), extracellular signalregulated kinases 1/2 (ERK1/2), the gelatinase network metalloproteinase-2 (MMP-2/9) and activator protein 1 (AP-1). In addition, ginsenosides also possess anti-inflammatory effects by inhibiting the formation of proinflammatory cytokines (tumor necrosis factor-α) (TNF-α) and interleukin-1β (IL-1β) and controlling the activities of inflammatory signalling pathways, such as NF-κB, Janus kinase2/signal transducer, and activator of transcription 3 (Jak2/Stat3).

CONCLUSION

In several in vitro and in vivo models, P. ginseng showed potential beneficial effects in lung cancer and inflammation treatment. In this review, we provide a detailed and up-to-date summary of research evidence for antilung cancer and anti-inflammatory protective effects of ginsenosides and their potential molecular mechanisms.

Anoikis-Associated Lung Cancer Metastasis: Mechanisms and Therapies

Simple Summary

Anoikis is a programmed cell death process resulting from the loss of interaction between cells and the extracellular matrix. Therefore, it is necessary to overcome anoikis when tumor cells acquire metastatic potential. In lung cancer, the composition of the extracellular matrix, cell adhesion-related membrane proteins, cytoskeletal regulators, and epithelial–mesenchymal transition are involved in the process of anoikis, and the initiation of apoptosis signals is a critical step in anoikis. Inversely, activation of growth signals counteracts anoikis. This review summarizes the regulators of lung cancer-related anoikis and explores potential drug applications targeting anoikis.

Abstract

Tumor metastasis occurs in lung cancer, resulting in tumor progression and therapy failure. Anoikis is a mechanism of apoptosis that combats tumor metastasis; it inhibits the escape of tumor cells from the native extracellular matrix to other organs. Deciphering the regulators and mechanisms of anoikis in cancer metastasis is urgently needed to treat lung cancer. Several natural and synthetic products exhibit the pro-anoikis potential in lung cancer cells and in vivo models. These products include artonin E, imperatorin, oroxylin A, lupalbigenin, sulforaphane, renieramycin M, avicequinone B, and carbenoxolone. This review summarizes the current understanding of the molecular mechanisms of anoikis regulation and relevant regulators involved in lung cancer metastasis and discusses the therapeutic potential of targeting anoikis in the treatment of lung cancer metastasis.

miR-29b Modulates Bone Marrow Mesenchymal Stem Cells (BMSCs) Differentiation and Induces Nerve Repair in Diabetic Retina Rat Model

microRNAs are involved in diabetic retinopathy (DR). This study intends to analyze miR-29b’s role in bone marrow mesenchymal stem cells (BMSCs) differentiation in DR rat models to induce nerve repair. BMSCs from DR rat models were cultured and transfected with miR-29b mimics and inhibitors followed by measuring miR-29b level, cell proliferation and apoptosis. Retinal ganglion cells (RGC) were treated with high glucose for 24 h, and BMSCs and si-miR-29b-BMSC were cocultured for 24 h, respectively followed by assessing cell proliferation and apoptosis, inflammatory cytokines by ELISA, MDA, SOD, brain-derived neurotrophic factor (BDNF) and ciliary neurotrophic factor (CNTF) level by ELISA. MiR-29b was up-regulated in BMSCs of DR rats. miR-29b mimics significantly up-regulated miR-29b, inhibited cell proliferation and promoted apoptosis (P < 0.05), which were reversed by miR-29b inhibitor (P < 0.05). Co-culture of BMSCs with si-miR-29b-BMSC promoted RGC proliferation, inhibited apoptosis and IL-6 secretion, decreased MDA, increased SOD, BDNF and CNTF expression (P < 0.05) with more significant changes in si-miR-29b-BMSC group (P < 0.05). In conclusion, down-regulation of miR-29b promotes BMSCs proliferation in DR rat models, inhibits BMSCs apoptosis, and promotes the recovery of retinal ganglion cell function.

Anti-atherosclerotic effects of geraniin through the gut microbiota-dependent trimethylamine N-oxide (TMAO) pathway in mice

BACKGROUND

Cardiovascular disease is a leading cause of death, which signifies the urgent need for effective anti-atherosclerotic strategies. Gut microbiota-dependent trimethylamine-N-oxide (TMAO) is associated with atherosclerosis, and geraniin, a natural polyphenol with various biological activities, might play key role in this process.

PURPOSE

We aimed to investigate the pharmacological activity of geraniin in atherosclerosis through remodeling the gut microbiota.

METHODS

C57BL/6J ApoE^-/- mice were administrated geraniin for 12 weeks. The colon contents were analyzed via 16S rRNA sequencing. Pathological staining was performed to evaluate the atherosclerotic characteristics. Cytokine assays detected the levels of plasma inflammatory cytokines. RAW264.7 cells were cultured in vitro and treated with TMAO. Tandem Mass Tag quantitative proteomics analysis and western blot were performed to investigate the effect of TMAO in macrophages.

RESULTS

The plasma TMAO level in mice significantly decreased after geraniin intervention. The predominant intestinal microflora from geraniin-treated mice were Bacteroides (65.3%) and Firmicutes (30.6%). Pathological staining demonstrated that administration of geraniin attenuated atherosclerotic characteristics. After geraniin treatment, plasma levels of IL-1β, IL-6, and TNF-α in mice were significantly reduced, and IL-10 levels were significantly increased. Proteomics analysis demonstrated the number of differentially expressed proteins after TMAO administration. In vitro study suggested that the atherogenic effect of TMAO could be attributed to changes in CD36, transmembrane protein 106a, apolipoprotein C1, macrophage scavenger receptor types I and II, and alpha-2-macroglobulin.

CONCLUSION

Geraniin might be an effective prospective drug against cardiovascular diseases, and the gut microbiota is a potential target to reduce the risk of atherosclerotic disease.

TGF-β1/SH2B3 axis regulates anoikis resistance and EMT of lung cancer cells by modulating JAK2/STAT3 and SHP2/Grb2 signaling pathways

The pathogenesis of lung cancer, the most common cancer, is complex and unclear, leading to limited treatment options and poor prognosis. To provide molecular insights into lung cancer development, we investigated the function and underlying mechanism of SH2B3 in the regulation of lung cancer. We indicated SH2B3 was diminished while TGF-β1 was elevated in lung cancer tissues and cells. Low SH2B3 level was correlated with poor prognosis of lung cancer patients. SH2B3 overexpression suppressed cancer cell anoikis resistance, proliferation, migration, invasion, and EMT, while TGF-β1 promoted those processes via reducing SH2B3. SH2B3 bound to JAK2 and SHP2 to repress JAK2/STAT3 and SHP2/Grb2/PI3K/AKT signaling pathways, respectively, resulting in reduced cancer cell anoikis resistance, proliferation, migration, invasion, and EMT. Overexpression of SH2B3 suppressed lung cancer growth and metastasis in vivo. In conclusion, SH2B3 restrained the development of anoikis resistance and EMT of lung cancer cells via suppressing JAK2/STAT3 and SHP2/Grb2/PI3K/AKT signaling cascades, leading to decreased cancer cell proliferation, migration, and invasion.

Geraniin inhibits whole blood IFN-γ and IL-6 and promotes IL-1β and IL-8, and stimulates calcium-dependent and sucrose-sensitive erythrocyte death

Correlations between circulating cytokine levels and disease states are well established, and pharmacological modulation of the immune response is thus an important aspect of the assessment of investigational new drugs. Moreover, chemotherapy-related anemia is a major obstacle in cancer treatment. Geraniin (GRN), a tannin extracted from Geranium and other plants, possesses promising antitumor potential. However, the effect of GRN on whole blood (WB) cytokine response and RBC physiology remains unexplored. Heparinized blood from consented, healthy adults was challenged with 100 ng/mL of lipopolysaccharide (LPS) with and without pretreatment with 10 μM of GRN for 24 h at 37 °C, and tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-1β (IL-1β), IL-6, IL-8, and IL-10 were assayed by ELISA. Moreover, single-cell RBC suspensions were treated with 5-100 μM of GRN for 24 or 48 h at 37 °C and cytotoxicity and canonical eryptotic markers were examined by flow cytometry. It was revealed that GRN significantly attenuated LPS-induced IFN-γ levels, increased IL-1β, decreased IL-6 only in absence of LPS, and aggravated LPS-induced IL-8 while together with LPS significantly diminished IL-10. Furthermore, GRN induced dose-responsive, Ca²⁺-dependent, and sucrose-sensitive hemolysis, along with phosphatidylserine exposure and Ca²⁺ accumulation with no appreciable cell shrinkage or oxidative damage. GRN was also selectively toxic to platelets, significantly delayed reticulocyte maturation, and significantly disrupted leukocyte proportions. In conclusion, GRN regulates the WB cytokine response and promotes premature hemolysis and eryptosis. This study provides insights into the therapeutic utility of GRN in a highly relevant cellular model system.

The role of polyphenols in overcoming cancer drug resistance: a comprehensive review

Chemotherapeutic drugs are used to treat advanced stages of cancer or following surgery. However, cancers often develop resistance against drugs, leading to failure of treatment and recurrence of the disease. Polyphenols are a family of organic compounds with more than 10,000 members which have a three-membered flavan ring system in common. These natural compounds are known for their beneficial properties, such as free radical scavenging, decreasing oxidative stress, and modulating inflammation. Herein, we discuss the role of polyphenols (mainly curcumin, resveratrol, and epigallocatechin gallate [EGCG]) in different aspects of cancer drug resistance. Increasing drug uptake by tumor cells, decreasing drug metabolism by enzymes (e.g. cytochromes and glutathione-S-transferases), and reducing drug efflux are some of the mechanisms by which polyphenols increase the sensitivity of cancer cells to chemotherapeutic agents. Polyphenols also affect other targets for overcoming chemoresistance in cancer cells, including cell death (i.e. autophagy and apoptosis), EMT, ROS, DNA repair processes, cancer stem cells, and epigenetics (e.g. miRNAs).

An overview on the role of plant-derived tannins for the treatment of lung cancer

Lung cancer is the leading cause of cancer-related death globally. Despite many advanced approaches to treat cancer, they are often ineffective due to resistance to classical anti-cancer drugs and distant metastases. Currently, alternative medicinal agents derived from plants are the major interest due to high bioavailability and fewer adverse effects. Tannins are polyphenolic compounds existing as specialized products in a wide variety of vegetables, fruits, and nuts. Many tannins have been found to possess protective properties, such as anti-inflammatory, anti-fibrotic, anti-microbial, anti-diabetic, and so on. This review aims to summarize the current knowledge addressing the anti-cancer effects of dietary tannins and their underlying molecular mechanisms. In vivo and in vitro studies provide evidences that anti-cancer effects of various tannins are predominantly mediated through negative regulation of transcription factors, growth factors, receptor kinases, and many oncogenic molecules. In addition, we also discussed the absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of tannins, clinical trial results as well as our perspective on future research with tannins.

Insights into the antitumor mechanism of ginsenosides Rg3

Panax ginseng, an ancient herb, belonging to Chinese traditional medicine, is an important herb that has a remarkable impact on various diseases. Ginsenoside Rg3, one of the most abundant ginsenosides, exerts significant functions in the prevention of various types of cancers with few side effects. In the present review, its functional molecular mechanisms are explored, including the improvement of antioxidant and anti-inflammation properties, immune regulation, induction of tumor apoptosis, prevention of tumor invasion and metastasis, tumor proliferation and angiogenesis, and reduction of chemoresistance and radioresistance. On the other hand, metabolism, pharmacokinetics and clinical indications of Rg3 are also discussed. The biological functional role of ginsenoside Rg3 may be associated with that it is a steroid glycoside with diverse biological activities and many signaling pathway can be regulated. Many clinical trials are highly needed to confirm the functions of ginsenoside Rg3.

Role of plasminogen activator inhibitor-1 in methotrexate-induced epithelial-mesenchymal transition in alveolar epithelial A549 cells

There is increasing evidence that epithelial-mesenchymal transition (EMT) contributes to the development of organ fibrosis. We demonstrated that methotrexate (MTX) clearly induced EMT through the transforming growth factor (TGF)-β-related signaling pathway in human alveolar epithelial cell line, A549. However, critical factors associated with MTX-induced EMT have not yet been identified. In our study, we attempted to identify factors playing a crucial role in MTX-induced EMT in A549 cells. We focused on plasminogen activator inhibitor-1 (PAI-1) as the possible target for the prevention of MTX-induced EMT-related lung injury. Comprehensive gene expression analysis by microarray revealed that mRNA expression level of PAI-1 was clearly increased by MTX treatment. In addition, using several cloned A549 cells, we found a good correlation between MTX-induced increase in mRNA expression levels of α-smooth muscle actin (SMA), a representative EMT marker, and PAI-1. Furthermore, MTX upregulated mRNA and protein expression levels of PAI-1 in A549 cells; this upregulation was canceled by co-treatment with SB431542, a TGF-β-related signaling pathway inhibitor. Notably, tiplaxtinin, a PAI-1 inhibitor, and knockdown of urokinase-type plasminogen activator receptor (uPAR) prevented MTX-induced EMT in A549 cells. These findings indicate that MTX may induce EMT via upregulation of PAI-1 expression and interaction of PAI-1 with uPAR in A549 cells.

Nobiletin in Cancer Therapy: How This Plant Derived-Natural Compound Targets Various Oncogene and Onco-Suppressor Pathways

Cancer therapy is a growing field, and annually, a high number of research is performed to develop novel antitumor drugs. Attempts to find new antitumor drugs continue, since cancer cells are able to acquire resistance to conventional drugs. Natural chemicals can be considered as promising candidates in the field of cancer therapy due to their multiple-targeting capability. The nobiletin (NOB) is a ubiquitous flavone isolated from Citrus fruits. The NOB has a variety of pharmacological activities, such as antidiabetes, antioxidant, anti-inflammatory, hepatoprotective, and neuroprotective. Among them, the antitumor activity of NOB has been under attention over recent years. In this review, we comprehensively describe the efficacy of NOB in cancer therapy. NOB induces apoptosis and cell cycle arrest in cancer cells. It can suppress migration and invasion of cancer cells via the inhibition of epithelial-to-mesenchymal transition (EMT) and EMT-related factors such as TGF-β, ZEB, Slug, and Snail. Besides, NOB inhibits oncogene factors such as STAT3, NF-κB, Akt, PI3K, Wnt, and so on. Noteworthy, onco-suppressor factors such as microRNA-7 and -200b undergo upregulation by NOB in cancer therapy. These onco-suppressor and oncogene pathways and mechanisms are discussed in this review.

Piperine Inhibits TGF-β Signaling Pathways and Disrupts EMT-Related Events in Human Lung Adenocarcinoma Cells

Background: Piperine, an amide extracted from the Piper spices, exhibits strong anti-tumor properties. However, its effect on the epithelial–mesenchymal transition (EMT) process has never been investigated. Herein, we evaluate the toxic effect of piperine on lung adenocarcinoma (A549), breast adenocarcinoma (MDA-MB-231) and hepatocellular carcinoma (HepG2) cell lines, as well as its ability to inhibit EMT-related events induced by TGF-β1 treatment. Methods: The cell viability was investigated by MTT assay. Protein expression was evaluated by Western blot. Gene expression was monitored by real-time PCR. Zymography assay was employed to detect metalloproteinase (MMP) activity in conditioned media. Cell motility was assessed by the wound-healing and phagokinetic gold sol assays. Results: The results revealed that piperine was cytotoxic in concentrations over 100 µM, showing IC50 values for HepG2, MDA-MB-231 and A549 cell lines of 214, 238 and 198 µM, respectively. In order to investigate whether piperine would reverse the TGF-β1 induced-EMT, the A549 cell line was pretreated with sublethal concentrations of the natural amide followed by the addition of TGF-β1. Besides disrupting EMT-related events, piperine also inhibited both ERK 1/2 and SMAD 2 phosphorylation. Conclusions: These results suggest that piperine might be further used in therapeutic strategies for metastatic cancer and EMT-related disorders.

Ginsenosides Rk1 and Rg5 inhibit transforming growth factor-β1-induced epithelial-mesenchymal transition and suppress migration, invasion, anoikis resistance, and development of stem-like features in lung cancer

Background

Lung cancer has a high incidence worldwide, and most lung cancer-associated deaths are attributable to cancer metastasis. Although several medicinal properties of Panax ginseng Meyer have been reported, the effect of ginsenosides Rk1 and Rg5 on epithelial-mesenchymal transition (EMT) stimulated by transforming growth factor beta 1 (TGF- β1) and self-renewal in A549 cells is relatively unknown.

Methods

We treated TGF-β1 or alternatively Rk1 and Rg5 in A549 cells. We used western blot analysis, real-time polymerase chain reaction (qPCR), wound healing assay, Matrigel invasion assay, and anoikis assays to determine the effect of Rk1 and Rg5 on TGF-mediated EMT in lung cancer cell. In addition, we performed tumorsphere formation assays and real-time PCR to evaluate the stem-like properties.

Results

EMT is induced by TGF-β1 in A549 cells causing the development of cancer stem-like features. Expression of E-cadherin, an epithelial marker, decreased and an increase in vimentin expression was noted. Cell mobility, invasiveness, and anoikis resistance were enhanced with TGF-β1 treatment. In addition, the expression of stem cell markers, CD44, and CD133, was also increased. Treatment with Rk1 and Rg5 suppressed EMT by TGF-β1 and the development of stemness in a dose-dependent manner. Additionally, Rk1 and Rg5 markedly suppressed TGF-β1-induced metalloproteinase-2/9 (MMP2/9) activity, and activation of Smad2/3 and nuclear factor kappa B/extra-cellular signal regulated kinases (NF-kB/ERK) pathways in lung cancer cells.

Conclusions

Rk1 and Rg5 regulate the EMT inducing TGF-β1 by suppressing the Smad and NF-κB/ERK pathways (non-Smad pathway).

MicroRNA-144-3p suppressed TGF-β1-induced lung cancer cell invasion and adhesion by regulating the Src-Akt-Erk pathway

Lung cancer remains a leading cause to cancer-related death worldwide. The anti-cancer ability of microRNA-144-3p has been reported in many cancer types. This study focused on the mechanisms underlying miR-144-3p in inhibiting lung cancer. The expression levels of miR-144-3p and steroid receptor coactivator (Src) in different lung cancer cell lines and those in bronchial epithelial cells (16HBE) were compared. miR-144-3p mimic and siSrc were transfected into A549 cells. Under the conditions of transforming growth factor-β1 (TGF-β1). Small interfering transfection or TGF-β1 treatment, cell invasive and adhesive abilities were analyzed by Transwell and cell adhesion assays. miR-144-3p inhibitor and siSrc were co-transfected into A549 cells and the changes in cell invasion and adhesion were detected. The activation of Src-protein kinase B-extracellular-regulated protein kinases (Src-Akt-Erk) pathway was determined using Western blot. The downregulated miR-144-3p and upregulated Src were generally detected in lung cancer cell lines and were the most significant genes in A549 cells. Both miR-144-3p overexpression and Src inhibition could obviously inhibit the invasion and adhesion abilities of A549 cells in the presence or absence of the effects of TGF-β1. The inhibition of Src could block the promotive effects of miR-144-3p inhibitor and TGF-β1 on cell invasion and adhesion. Furthermore, we found that miR-144-3p could negatively regulate the phosphorylation levels of Akt and Erk. Our data indicated the essential role of Src in the mechanisms underlying TGF-β1-induced cell invasion and adhesion of lung cancer, and that miR-144-3p could effectively suppress TGF-β1-induced aggressive lung cancer cells by regulating Src expression.

Bioactive Compounds: Natural Defense Against Cancer?

Cancer is a devastating disease that has claimed many lives. Natural bioactive agents from plants are gaining wide attention for their anticancer activities. Several studies have found that natural plant-based bioactive compounds can enhance the efficacy of chemotherapy, and in some cases ameliorate some of the side-effects of drugs used as chemotherapeutic agents. In this paper, we have reviewed the literature on the anticancer effects of four plant-based bioactive compounds namely, curcumin, myricetin, geraniin and tocotrienols (T3) to provide an overview on some of the key findings that are related to this effect. The molecular mechanisms through which the active compounds may exert their anticancer properties in cell and animal-based studies also discussed.

Reversal of Epithelial-Mesenchymal Transition by Natural Anti-Inflammatory and Pro-Resolving Lipids

Epithelial mesenchymal transition (EMT) is a key process in the progression of malignant cancer. Therefore, blocking the EMT can be a critical fast track for the development of anticancer drugs. In this paper, we update recent research output of EMT and we explore suppression of EMT by natural anti-inflammatory compounds and pro-resolving lipids.

Geraniin inhibits oral cancer cell migration by suppressing matrix metalloproteinase-2 activation through the FAK/Src and ERK pathways

Geraniin has been reported to have numerous biological activities, including antiviral, antihypertensive, antihyperglycaemic, liver protective, antidiabetic, and apoptotic activities. However, the anti-migration effects of geraniin on oral cancer remain elusive. In this study, we revealed the potential antitumor mechanisms of geraniin through the inhibition of the migration and invasion of human oral cancer cell lines SCC-9 and SCC-14. The results of gelatin zymography and Western blot assays revealed that geraniin significantly reduced the activity and expression of matrix metalloproteinase-2 (MMP-2) of oral cancer cells in a concentration-dependent manner. Furthermore, geraniin potently suppressed the phosphorylation of focal adhesion kinase (FAK), Src, and extracellular signal-regulated kinase (ERK)1/2 but did not affect the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase 1/2. Moreover, blocking the MAPK/ERK1/2 pathway significantly enhanced the anti-migration ability of geraniin in oral cancer cells. In conclusion, we demonstrated that geraniin inhibits the motility of SCC-9 and SCC-14 cells in vitro through a molecular mechanism that involves the attenuation of MMP-2 expression and activity mediated by decreased FAK/Src and ERK1/2 pathways.

Geraniin Attenuates Lipopolysaccharide-Induced Cognitive Impairment in Mice by Inhibiting Toll-Like Receptor 4 Activation

Geraniin has been reported to possess potent anti-inflammatory properties and to modulate the macrophage polarization. This study sought to evaluate the protective effects and underlying mechanisms of geraniin on lipopolysaccharide (LPS)-induced neuroinflammation and neurobiological alternations as well as cognitive impairment. Daily intragastrical administration with geraniin (20 mg kg^-1 day^-1) for 14 days significantly prolonged the duration in the target quadrant (26.53 ± 2.03 versus 37.09 ± 3.27%; p < 0.05) and increased crossing-target number (1.93 ± 0.22 versus 3.08 ± 0.17; p < 0.01) in the probe test of LPS-treated mice. Geraniin also ameliorated LPS-elicited neural/synaptic impairments and decreased levels of LPS-induced Aβ generation (p < 0.05), amyloid precursor protein (APP) (p < 0.05) and β-site amyloid precursor protein cleavage enzyme 1 (BACE1) (p < 0.05). Furthermore, geraniin suppressed the production of pro-inflammatory cytokines, including tumor necrosis factor α (TNF-α) (9.85 ± 0.58 versus 5.20 ± 0.52 pg/mg of protein; p < 0.01), interleukin (IL)-1β (16.31 ± 0.67 versus 8.62 ± 0.46 pg/mg of protein; p < 0.01), and IL-6 (12.12 ± 0.45 versus 7.43 ± 0.32 pg/mg of protein; p < 0.05), and inhibited glial cell activation. Moreover, geraniin effectively polarized the microglia toward an anti-inflammatory M2 phenotype. Further study revealed that geraniin targeted toll-like receptor 4 (TLR4)-mediated signaling and decreased the production of pro-inflammatory cytokines in BV-2 microglial cells. These results indicate that geraniin mitigates LPS-elicited neural/synaptic neurodegeneration, amyloidogenesis, neuroinflammation, and cognitive impairment and suggest geraniin as a therapeutic option for neuroinflammation-associated neurological disorders, such as Alzheimer's disease.

Geraniin Differentially Modulates Chromosome Stability of Colon Cancer and Noncancerous Cells by Oppositely Regulating their Spindle Assembly Checkpoint

Geraniin has been reported to specifically induce apoptosis in multiple human cancers, but the underlying mechanism is poorly defined. The spindle assembly checkpoint (SAC) is a surveillance system to ensure high-fidelity chromosome segregation during mitosis. Weakening of SAC to enhance chromosome instability (CIN) can be therapeutic because very high levels of CIN are lethal. In this study, we have investigated the effects of geraniin on the SAC of colorectal cancer HCT116 cells and noncancerous colon epithelial CCD841 cells. We find that treatment of HCT116 cells with geraniin leads to dose-dependent decrease of cell proliferation, colony formation, and anchorage-independent growth. Geraniin is found to induce apoptosis in mitotic and postmitotic HCT116 cells. Furthermore, geraniin weakens the SAC function of HCT116 cells by decreasing the transcriptional expression of several SAC kinases (particularly Mad2 and Bub1), which in turn leads to premature anaphase entry, mitotic aberrations, and CIN in HCT116 cells. In contrast, the proliferation of CCD841 cells is slightly inhibited by geraniin. Even more interestingly, geraniin increases the transcriptional expression of several SAC kinases (e.g., Mad1 and BubR1) to strengthen SAC efficiency, which contributes to the reduction of mitotic aberrations and CIN in CCD841 cells. Altogether, our findings reveal that the SAC pathway in human colon cancer and noncancerous cell lineages responses oppositely to geraniin treatment, resulting CIN promotion and suppression, respectively. Specific abrogation of SAC to induce catastrophic CIN in HCT116 cells may account for the selective anticancer action of geraniin.. Environ. Mol. Mutagen. 60:254-268, 2019. © 2018 Wiley Periodicals, Inc.

Emodin Inhibits Colon Cancer Cell Invasion and Migration by Suppressing Epithelial-Mesenchymal Transition via the Wnt/β-Catenin Pathway

Colon cancer (CC) is the third most common cancer worldwide. Emodin is an anthraquinone-active substance that has the ability to affect tumor progression. Our study aims to explore the effects and the relevant mechanism of emodin on the invasion and migration of CC in vitro and in vivo. In our study, we found that emodin inhibited the invasion and migration abilities of RKO cells and decreased the expression of matrix metalloproteinase-7 (MMP-7), MMP-9, and vascular endothelial growth factor (VEGF) in a dose-dependent manner. Further research suggested that emodin inhibited EMT by increasing the mRNA level of E-cadherin and decreasing the expression of N-cadherin, Snail, and β-catenin. Emodin also significantly inhibited the activation of the Wnt/β-catenin signaling pathway by downregulating the expression of related downstream target genes, including TCF4, cyclin D1, and c-Myc. A Wnt/β-catenin signaling pathway agonist abolished the effect of emodin on EMT and cell mobility, suggesting that emodin exerted its regulating role through the Wnt/β-catenin pathway. The CC xenograft model was established to study the antitumor efficiency of emodin in vivo. The in vivo study further demonstrated that emodin (40 mg/kg) suppressed tumor growth by inhibiting EMT via the Wnt/β-catenin signaling pathway in vivo. Taken together, we suggest that emodin inhibits the invasion and migration of CC cells in vitro and in vivo by blocking EMT, which is related with the inhibition of the Wnt/β-catenin signaling pathway.

Novel TGF-β1 inhibitor antagonizes TGF-β1-induced epithelial-mesenchymal transition in human A549 lung cancer cells

Transforming growth factor β1 (TGF-β1), a multifunctional cytokine, is known to promote tumor invasion and metastasis and induce epithelial-mesenchymal transition (EMT) in various cancer cells. Inhibition of TGF-β1 signaling is a new strategy for cancer therapy. Most cancer cells display altered or nonfunctional TGF-β1 signaling; hence, TGF-β1 inhibitors exert limited effects on these cells. Recent studies have suggested that developing a TGF-β1 inhibitor from natural compounds is a key step to create novel therapeutic agents. This study aimed to develop a new anti-TGF-β1 therapy for cancer. We found an improved analog of chalcones, compound 67, and investigated its effects in vitro. We demonstrated the inhibitory role of compound 67 through migration and invasion assays on TGF-β1-induced EMT of human A549 lung cancer cells. Compound 67 inhibited TGF-β1-induced smad2 phosphorylation, suppressed TGF-β1-induced EMT markers, matrix metalloproteinase-2 (MMP-2) and MMP-9, and inhibited migration and invasion of A549 cells. The study results showed that compound 67 is useful to prevent tumor growth and metastasis.

Hypaconitine inhibits TGF-β1-induced epithelial-mesenchymal transition and suppresses adhesion, migration, and invasion of lung cancer A549 cells

Epithelial-mesenchymal transition (EMT) has been implicated in tumor invasion and metastasis and provides novel strategies for cancer therapy. Hypaconitine (HpA), a diester-diterpenoid alkaloid isolated from the root of the Aconitum species, exhibits anti-inflammatory, analgesic, and especially, cardiotoxic activities. Here, we reported the anti-metastatic potentials of HpA in transforming growth factor-β1 (TGF-β1)-induced EMT in lung cancer A549 cells. The cytotoxic effect of HpA was determined by MTT assay. A549 cells were treated with TGF-β1 with or without HpA co-treatment, and the morphological alterations were observed with a microscopy. The expression of E-cadherin, N-cadherin, and NF-κB was determined by both Western blotting and immunofluorescence analyses. The adhesion, migration, and invasion were detected with Matrigel, wound-healing, and transwell assays, respectively. The expression of Snail was determined by Western blotting. The expression of NF-κB p65, IκBα, and p-IκBα in nuclear and cytosolic extracts was assessed by Western blotting. The results showed that low concentration of HpA (<16 μmol·L^-1) had no obvious cytotoxicity to A549 cells. Morphologically, TGF-β1 treatment induced spindle-shaped alteration in the cells. The upregulation of N-cadherin, NF-κB, and Snail and the downregulation of E-cadherin were detected after TGF-β1 treatment. The adhesion, migration and invasion abilities were also increased by TGF-β1. Besides, TGF-β1 induced expression of Snail in a time-dependent manner. Furthermore, TGF-β1 induced nuclear translocation of NF-κB p65. All these alterations were dramatically inhibited by HpA co-treatment. In addition, the NF-κB inhibitor PDTC showed similar inhibitory effect. In conclusion, these results showed that HpA inhibited TGF-β1-induced EMT in A549 cells, which was possibly mediated by the inactivation of the NF-κB signaling pathway, providing an evidence for anti-cancer effect of HpA.

Phoyunnanin E inhibits migration of non-small cell lung cancer cells via suppression of epithelial-to-mesenchymal transition and integrin αv and integrin β3

BACKGROUND

The conversion of the epithelial phenotype of cancer cells into cells with a mesenchymal phenotype-so-called epithelial-mesenchymal transition (EMT)-has been shown to enhance the capacity of the cells to disseminate throughout the body. EMT is therefore becoming a potential target for anti-cancer drug discovery. Here, we showed that phoyunnanin E, a compound isolated from Dendrobium venustum, possesses anti-migration activity and addressed its mechanism of action.

METHODS

The cytotoxic and proliferative effects of phoyunnanin E on human non-small cell lung cancer-derived H460, H292, and A549 cells and human keratinocyte HaCaT cells were investigated by MTT assay. The effect of phoyunnanin E on EMT was evaluated by determining the colony formation and EMT markers. The migration and invasion of H460, H292, A549 and HaCaT cells was evaluated by wound healing assay and transwell invasion assay, respectively. EMT markers, integrins and migration-associated proteins were examined by western blot analysis.

RESULTS

Phoyunnanin E at the concentrations of 5 and 10 μM, which are non-toxic to H460, H292, A549 and HaCaT cells showed good potential to inhibit the migratory activity of three types of human lung cancer cells. The anti-migration effect of phoyunnanin E was shown to relate to the suppressed EMT phenotypes, including growth in anchorage-independent condition, cell motility, and EMT-specific protein markers (N-cadherin, vimentin, slug, and snail). In addition to EMT suppression, we found that phoyunnanin E treatment with 5 and 10 μM could decrease the cellular level of integrin αv and integrin β3, these integrins are frequently up-regulated in highly metastatic tumor cells. We further characterized the regulatory proteins in cell migration and found that the cells treated with phoyunnanin E exhibited a significantly lower level of phosphorylated focal adhesion kinase (p-FAK) and phosphorylated ATP-dependent tyrosine kinase (p-AKT), and their downstream effectors (including Ras-related C3 botulinum (Rac-GTP); Cell division cycle 42 (Cdc42); and Ras homolog gene family, member A (Rho-GTP)) in comparison to those of the non-treated control.

CONCLUSIONS

We have determined for the first time that phoyunnanin E could inhibit the motility of lung cancer cells via the suppression of EMT and metastasis-related integrins. This new information could support further development of this compound for anti-metastasis approaches.

Delphinidin inhibits BDNF-induced migration and invasion in SKOV3 ovarian cancer cells

Brain-derived neurotrophic factor (BDNF), the TrkB ligand, is associated with aggressive malignant behavior, including migration and invasion, in tumor cells and a poor prognosis in patients with various types of cancer. Delphinidin is a diphenylpropane-based polyphenolic ring structure-harboring compound, which exhibits a wide range of pharmacological activities, anti-tumor, anti-oxidant, anti-inflammatory, anti-angiogenic and anti-mutagenic activity. However, the possible role of delphinidin in the cancer migration and invasion is unclear. We investigated the suppressive effect of delphinidin on the cancer migration and invasion. Thus, we found that BDNF enhanced cancer migration and invasion in SKOV3 ovarian cancer cell. To exam the inhibitory role of delphinidin in SKOV3 ovarian cancer migration and invasion, we investigated the use of delphinidin as inhibitors of BDNF-induced motility and invasiveness in SKOV3 ovarian cancer cells in vitro. Here, we found that delphinidin prominently inhibited the BDNF-induced increase in cell migration and invasion of SKOV3 ovarian cancer cells. Furthermore, delphinidin remarkably inhibited BDNF-stimulated expression of MMP-2 and MMP-9. Also, delphinidin antagonized the phosphorylation of Akt and nuclear translocation of NF-κB permitted by the BDNF in SKOV3 ovarian cancer cells. Taken together, our findings provide new evidence that delphinidin suppressed the BDNF-induced ovarian cancer migration and invasion through decreasing of Akt activation.

An UPLC Method for Determination of Geraniin in Rat Plasma and its Application to Pharmacokinetic Studies

Introduction:

Geraniin has many biological activities including anti-osteoporotic and anti-hyperglycemic efficacies.

Materials and Methods:

A rapid and simple method for the determination of geraniin in rat plasma using ultra performance liquid chromatography coupled to ultraviolet detector was developed. The plasma sample, spiked with epicatechin as an internal standard, was subjected to ethyl acetate extraction prior to analysis. Chromatographic separation was performed on the HSS T3 column and monitored at a wavelength of 280 nm. The limit of detection and lower limit of quantification was 0.07 μg/mL and 0.2 μg/mL in rat plasma, respectively.

Conclusion:

Good linearity was obtained in the range of 0.2 - 200 μg/mL, and the correlation coefficient was better than 0.997. The intra-day and inter-day precisions decreased 9.8%. The accuracy of QC samples ranged from 84.4% to 87.1%. The extraction recovery ranged from 88.4% to 90.3% and the matrix effect ranged from 84.4% to 87.2%. The analyte was stable in rat plasma when stored at room temperature for 12 hours, 4°C for 24 hours and -20°C for 15 days. t1/2 and t1/2 for i.v. was 0.21 ± 0.10 and 7.20 ± 2.20 h, respectively. Plasma clearance (CL) was 0.03 ± 0.02 L/h/kg and apparent volume of distribution (Vz) was 0.05 + 0.01 L/kg. The developed method was successfully applied to the pharmacokinetic study of geraniin in rats.

Geraniin suppresses ovarian cancer growth through inhibition of NF-κB activation and downregulation of Mcl-1 expression

This study investigated the anticancer effects of geraniin on ovarian cancer cells and the signaling pathways involved. Ovarian cancer cells were treated with different concentrations of geraniin for 48 h and examined for viability, apoptosis, mitochondrial membrane depolarization, and gene expression. Xenograft tumor studies were performed to determine the anticancer activity of geraniin in vivo. Geraniin significantly decreased cancer cell viability in a concentration-dependent fashion. Geraniin significantly triggered apoptosis, which was accompanied by loss of mitochondrial membrane potential and increased cytochrome c release and caspsase-3 activity. Mechanistically, geraniin significantly downregulated Mcl-1 and impaired NF-κB p65 binding to the mcl-1 promoter. Overexpression of Mcl-1 significantly reversed geraniin-induced apoptosis in OVCAR3 cells. In addition, geraniin retarded ovarian cancer growth and reduced expression of phospho-p65 and Mcl-1. Collectively, geraniin elicits growth suppression in ovarian cancer through inhibition of NF-κB and Mcl-1 and may provide therapeutic benefits for this malignancy.

Dioscin suppresses TGF-β1-induced epithelial-mesenchymal transition and suppresses A549 lung cancer migration and invasion

Epithelial-to-mesenchymal transition (EMT), an important cellular process, occurs during cancer development and progression, has a crucial role in metastasis by enhancing the motility of tumor cells. Dioscin is a polyphenolic component isolated from Phyllanthus amarus, which exhibits a wide range of pharmacological and physiological activities, such as anti-tumor, anti-inflammatory, anti-obesity, anti-fungal, and anti-viral activities. However, the possible role of dioscin in the EMT is unclear. We investigated the suppressive effect of dioscin on the EMT. Transforming growth factor-beta 1 (TGF-β1) is known to induce EMT in a number of cancer cell types and promote lung adenocarcinoma migration and invasion. To verify the inhibitory role of dioscin in lung cancer migration and invasion, we investigated the use of dioscin as inhibitors of TGF-β1-induced EMT in A549 lung cancer cells in vitro. Here, we found that dioscin prominently increased expression of the epithelial marker E-cadherin and expression of the mesenchymal marker N-cadherin and Snail during the TGF-β1-induced EMT. In addition, dioscin inhibited the TGF-β1-induced increase in cell migration and invasion of A549 lung cancer cells. Also, dioscin remarkably inhibited TGF-β1-regulated activation of MMP-2/9, Smad2, and p38. Taken together, our findings provide new evidence that dioscin suppresses lung cancer migration, and invasion in vitro by inhibiting the TGF-β1-induced EMT.

Geraniin Inhibits LPS-Induced THP-1 Macrophages Switching to M1 Phenotype via SOCS1/NF-κB Pathway

M1 macrophage polarization is proved to promote inflammation in atherosclerosis process. In this study, we evaluated the inhibitory effect of geraniin, a bioactive polyphenolic compound, on the LPS-induced switch of THP-1 macrophages to M1 phenotype, and we propose a molecular basis for its action. Flow cytometry analysis indicated that geraniin significantly inhibited LPS-induced M1 macrophage polarization. Geraniin downregulated the protein and the mRNA level of typical cytokines of M1 macrophage, including tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6), indicating that geraniin can suppress typical mediators of M1 macrophage at the transcriptional level. Moreover, geraniin inhibited LPS-induced reactive oxygen species (ROS) and nitric oxide (NO) production, as well as inducible nitric oxide synthase (iNOS) activity, in THP-1 macrophages. Furthermore, western blot analysis indicated that geraniin decreased both LPS-induced phosphorylation of NF-κB-p65 and NF-κB-p65 expression without affecting the level of IκB-α. This suggested that geraniin inhibited NF-κB, a transcription factor pivotal in the LPS-induced expression of pro-inflammatory genes and an important player in M1 macrophage polarization. Moreover, an electrophoretic mobility shift assay (EMSA) demonstrated that geraniin blocked the LPS-induced translocation of NF-κB to the nucleus. Moreover, we found that geraniin up-regulated the expression of SOCS1, an upstream regulator of NF-κB activation that can directly bind to NF-κB-p65 and downregulate it, thus inhibiting NF-κB activation. In conclusion, geraniin inhibits LPS-induced THP-1 macrophages switching to M1 phenotype through SOCS1/NF-κB pathway.

Morus alba Leaf Lectin (MLL) Sensitizes MCF-7 Cells to Anoikis by Inhibiting Fibronectin Mediated Integrin-FAK Signaling through Ras and Activation of P38 MAPK

Lectins are a unique class of carbohydrate binding proteins/glycoproteins, and many of them possess anticancer properties. They can induce cell cycle arrest and apoptosis, inhibit protein synthesis, telomerase activity and angiogenesis in cancer cells. In the present study, we have demonstrated the effect of Morus alba leaf lectin (MLL) on anoikis induction in MCF-7 cells. Anoikis induction in cancer cells has a significant role in preventing early stage metastasis. MLL treatment in monolayers of MCF-7 cells caused significant detachment of cells in a time and concentration dependent manner. The detached cells failed to re-adhere and grew even to culture plates coated with different matrix proteins. DNA fragmentation, membrane integrity studies, annexin V staining, caspase 9 activation and upregulation of Bax/Bad confirmed that the detached cells underwent apoptosis. Upregulation of matrix metalloproteinase 9 (MMP-9) caused a decrease in fibronectin (FN) production which facilitated the cells to detach by blocking the FN mediated downstream signaling. On treatment with MLL, we have observed downregulation of integrin expression, decreased phosphorylation of focal adhesion kinase (FAK), loss in FAK-integrin interaction and active Ras. MLL treatment downregulated the levels of phosphorylated Akt and PI3K. Also, we have studied the effect of MLL on two stress activated protein kinases p38 MAPK and JNK. p38 MAPK activation was found to be elevated, but there was no change in the level of JNK. Thus our study substantiated the possible antimetastatic effect of MLL by inducing anoikis in MCF-7 cells by activation of caspase 9 and proapoptotic Bax/Bad by blockage of FN mediated integrin/FAK signaling and partly by activation of p38 MAPK.

Combined treatment with zingerone and its novel derivative synergistically inhibits TGF-β1 induced epithelial-mesenchymal transition, migration and invasion of human hepatocellular carcinoma cells

The epithelial-mesenchymal transition (EMT) is an important cellular process during which polarized epithelial cells become motile mesenchymal cells, which promote cancer metastasis. Ginger, the rhizome of Zingiber officinale, is extensively used in cooking worldwide and also as a traditional medicinal herb with antioxidant, anti-inflammatory and anticancer properties. Several pungent compounds have been identified in ginger, including zingerone, which has anticancer potential. However, the role of zingerone in EMT is unclear. We investigated the synergistic effect of zingerone and its derivative on EMT. Transforming growth factor-beta 1 (TGF-β1) induces the EMT to promote hepatocellular carcinoma metastasis, including migration and invasion. To understand the repressive role of the combination of zingerone and its derivative (ZD 2) in hepatocellular carcinoma metastasis, we investigated the potential use of each compound of ginger, such as zingerone, ZD 2 and 6-shogaol, or the mixture of zingerone and ZD 2 (ZD 2-1) as inhibitors of TGF-β1 induced EMT development in SNU182 hepatocellular carcinoma cells in vitro. We show that ZD 2-1, but not zingerone, ZD 2 and 6-shogaol significantly increased expression of the epithelial marker E-cadherin and repressed Snail upregulation and expression of the mesenchymal marker N-cadherin during initiation of the TGF-β1 induced EMT. In addition, ZD 2-1 inhibited the TGF-β1 induced increase in cell migration and invasion of SNU182 hepatocellular carcinoma cells. Furthermore, ZD 2-1 significantly inhibited TGF-β1 regulated matrix metalloproteinase-2/9 and activation of Smad2/3. We also found that ZD 2-1 inhibited nuclear translocation of NF-κB, activation of p42/44 MAPK/AP1 signaling pathway in the TGF-β1 induced EMT. Our findings provide new evidence that combined treatment with ZD 2, novel zingerone derivative, and zingerone synergistically suppresses hepatocellular carcinoma metastasis in vitro by inhibiting the TGF-β1 induced EMT.

Doxycycline reverses epithelial-to-mesenchymal transition and suppresses the proliferation and metastasis of lung cancer cells

The gelatinase inhibitor doxycycline is the prototypical antitumor antibiotic. We investigated the effects of doxycycline on the migration, invasion, and metastasis of human lung cancer cell lines and in a mouse model. We also measured the effect of doxycycline on the transcription of epithelial-mesenchymal transition (EMT) markers, and used immunohistochemistry to determine whether EMT reversal was associated with doxycycline inhibition. Doxycycline dose-dependently inhibited proliferation, migration, and invasion of NCI-H446 human small cell lung cancer cells. It also suppressed tumor growth from NCI-H446 and A549 lung cancer cell xenografts without altering body weight, inhibited Lewis lung carcinoma cell migration, and prolonged survival. The activities of the transcription factors Twist1/2, SNAI1/2, AP1, NF-κB, and Stat3 were suppressed by doxycycline, which reversed EMT and inhibited signal transduction, thereby suppressing tumor growth and metastasis. Our data demonstrate functional targeting of transcription factors by doxycycline to reverse EMT and suppress tumor proliferation and metastasis. Thus, doxycycline selectively targets malignant tumors and reduces its metastatic potential with less cytotoxicity in lung cancer patients.

The relationship between vasculogenic mimicry and epithelial-mesenchymal transitions

Vasculogenic mimicry (VM) is a vascular‐like structure which can mimic the embryonic vascular network pattern to nourish the tumour tissue. As a unique perfusion way, VM is correlated with tumour progression, invasion, metastasis and lower 5‐year survival rate. Notably, epithelial‐mesenchymal transition (EMT) regulators and EMT‐related transcription factors are highly up‐regulated in VM‐forming tumour cells, which demonstrated that EMT may play a crucial role in VM formation. Therefore, the up‐regulation of EMT‐associated adhesion molecules and other factors can also make a contribution in VM‐forming process. Depending on these discoveries, VM and EMT can be utilized as therapeutic target strategies for anticancer therapy. The purpose of this article is to explore the advance research in the relationship of EMT and VM and their corresponding mechanisms in tumorigenesis effect.

Nobiletin inhibits epithelial-mesenchymal transition of human non-small cell lung cancer cells by antagonizing the TGF-β1/Smad3 signaling pathway

Epithelial-mesenchymal transition (EMT) is a critical cellular process in cancer metastasis, during which epithelial polarized cells become motile mesenchymal cells. Since transforming growth factor-β (TGF-β) is a potent inducer of EMT, blocking of TGF-β/Smad signaling has become a promising cancer therapy. Nobiletin, a polymethoxy flavonoid from Citrus depressa, has been shown to be valuable for cancer treatment, yet the mechanism remains unclear. In the present study, lung adenocarcinoma A549 and H1299 cells were used to evaluate the effect of nobiletin on EMT induced by TGF-β1. Nobiletin successfully inhibited TGF-β1-induced EMT, migration, invasion and adhesion in vitro, accompanied by attenuation of MMP-2, MMP-9, p-Src, p-FAK, p-paxillin, Snail, Slug, Twist and ZEB1 expression. Nobiletin inhibited the transcriptional activity of Smads without changing the phosphorylation status or translocation of Smads induced by TGF-β1. Moreover, Smad3 is requisite in TGF-β1-stimulated EMT. Smad3 overexpression meaningfully impaired the ability of nobiletin to reverse TGF-β1-induced EMT. In vivo, nobiletin prohibited the growth of metastatic nodules in the lungs of nude mice. Moreover, nobiletin inhibited tumor growth and reversed EMT in mice bearing A549-Luc xenografts, as revealed by IVIS imaging and immunohistochemical analysis. Collectively, the data suggest that nobiletin prevents EMT by inactivating TGF-β1/Smad3 signaling.

Sanguiin H6 suppresses TGF-β induction of the epithelial-mesenchymal transition and inhibits migration and invasion in A549 lung cancer

In the epithelial-mesenchymal transition (EMT), an important cellular process, epithelial cells become mesenchymal cells. This process is also critically involved in cancer metastasis. Sanguiin H6 is a compound derived from ellagitannin, which is found in berries. Sanguiin H6 shows various pharmacological properties, including anti-angiogenic activity. Because the possible role of sanguiin H6 in the EMT and the underlying molecular mechanisms are unclear, we investigated the effect of sanguiin H6 on the EMT. Transforming growth factor-beta 1 (TGF-β1) induces the EMT and promotes lung adenocarcinoma migration and invasion through the Smad2/3 signaling pathway. Thus, to understand the inhibitory effects of sanguiin H6 on lung cancer migration and invasion, we investigated the ability of sanguiin H6 to inhibit TGF-β1-induced EMT in the A549 cell line. We found that sanguiin H6 significantly prevented the activation of Smad2/3 signaling pathway by TGF-β1. Additionally, sanguiin H6 increased the expression of the epithelial marker E-cadherin and repressed the expression of Snail and the mesenchymal marker N-cadherin during TGF-β1-induced EMT. Moreover, sanguiin H6 regulated the expression of EMT-dependent genes induced by TGF-β1. Finally, sanguiin H6 inhibited the migration and invasion of TGF-β1-stimulated A549 cells. Taken together, our findings provide new evidence that sanguiin H6 suppresses lung cancer migration and invasion in vitro by inhibiting TGF-β1 induction of the EMT.