2-Hydroxycinnamaldehyde inhibits the epithelial-mesenchymal transition in breast cancer cells

Cinnamon oil as a co-chemotherapy agent through inhibition of cell migration and MMP-9 expression on 4T1 cells

OBJECTIVES

The long-term and high-dose use of doxorubicin as chemotherapy for triple-negative breast cancer (TNBC) patients induces epithelial-to-mesenchymal transition (EMT) and stimulates cancer metastasis. Cinnamaldehyde is a major compound of cinnamon oil (CO) suppressing Snail and NFκB activity that are involved in cell migration. This study aims to explore the activity of CO as a co-chemotherapeutic agent on 4T1 breast cancer cells.

METHODS

The CO was obtained by water and steam distillation and was characterized phytochemically by gas chromatography-mass spectrometry (GC-MS). Cytotoxic activity of single CO or in combination with doxorubicin was observed by MTT assay. Cell migration and MMP-9 expression were measured by scratch wound healing and gelatin zymography assays. The intracellular reactive oxygen species (ROS) levels were observed by 2',7'-dichlorofluorescin diacetate (DCFDA) staining flowcytometry.

RESULTS

The phytochemical analysis with GC-MS showed that CO contains 14 compounds with cinnamaldehyde as the major compound. CO exhibited cytotoxicity on 4T1 cells with the IC₅₀ value of 25 μg/mL and its combination with doxorubicin decreased cell viability and inhibited cell migration compared to a single use. Furthermore, the combination of CO and doxorubicin inhibited MMP-9 expression and elevated intracellular ROS levels compared to control.

CONCLUSIONS

CO has the potential to be developed as a co-chemotherapy agent through inhibition of cell migration, and intracellular ROS levels elevation.

Regulation of ROS-Dependent JNK Pathway by 2'-Hydroxycinnamaldehyde Inducing Apoptosis in Human Promyelocytic HL-60 Leukemia Cells

The present study demonstrated that 2'-hydroxycinnamaldehyde (2'-HCA) induced apoptosis in human promyelocytic leukemia HL-60 cells through the activation of mitochondrial pathways including (1) translocation of Bim and Bax from the cytosol to mitochondria, (2) downregulation of Bcl-2 protein expression, (3) cytochrome c release into the cytosol, (4) loss of mitochondrial membrane potential (ΔΨ_m), and (5) caspase activation. 2'-HCA also induced the activation of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase1/2 (ERK1/2) in HL-60 cells. The pharmacological and genetic inhibition of JNK effectively prevented 2'-HCA-induced apoptosis and activator protein-1 (AP-1)-DNA binding. In addition, 2'-HCA resulted in the accumulation of reactive oxygen species (ROS) and depletion of intracellular glutathione (GSH) and protein thiols (PSH) in HL-60 cells. NAC treatment abrogated 2'-HCA-induced JNK phosphorylation, AP-1-DNA binding, and Bim mitochondrial translocation, suggesting that oxidative stress may be required for 2'-HCA-induced intrinsic apoptosis. Xenograft mice inoculated with HL-60 leukemia cells demonstrated that the intraperitoneal administration of 2'-HCA inhibited tumor growth by increasing of TUNEL staining, the expression levels of nitrotyrosine and pro-apoptotic proteins, but reducing of PCNA protein expression. Taken together, our findings suggest that 2'-HCA induces apoptosis via the ROS-dependent JNK pathway and could be considered as a potential therapeutic agent for leukemia.

2'-Hydroxycinnamaldehyde ameliorates imiquimod-induced psoriasiform inflammation by targeting PKM2-STAT3 signaling in mice

2′-Hydroxycinnamaldehyde (HCA), the active component isolated from the stem bark of Cinnamomum cassia, exerts anticancer effects through multiple mechanisms. We recently determined that HCA inhibits signal transducer and activator of transcription 3 (STAT3) signaling in prostate cancer cells. Because STAT3 overactivation has been closely associated with the development of psoriasis, a chronic autoimmune skin disease, we examined whether HCA ameliorates skin lesions in an imiquimod-induced psoriasis-like mouse model. The results showed that intraperitoneal administration of HCA alleviated imiquimod-induced psoriasis-like dermatitis, epidermal thickening, dermal infiltration of inflammatory cells, and proinflammatory cytokine production. Mechanistically, HCA inhibited pyruvate kinase isozyme M2 and STAT3 signaling, leading to the suppression of T cell activation, Th17 cell differentiation, and keratinocyte hyperproliferation. These results suggest that HCA may be a new treatment for psoriasis and other STAT3-mediated skin disorders, such as infection, inflammation and carcinogenesis.

An active compound found in cinnamon bark could help alleviate the symptoms of psoriasis according to a study in mice by researchers in South Korea. A team led by Eun Ju Bae and Byung-Hyun Park from Chonbuk National University in Jeonju administered 2′-hydroxycinnamaldehyde, a molecule derived from cinnamon, to mice with drug-induced psoriatic skin lesions. After the treatment, the mice showed fewer signs of skin irritation, with less inflammation and no detectable ill effects. The researchers showed that the drug blocked an enzyme that normally activates a central regulator of immune responses in the skin. Consequently, fewer proinflammatory T cells infiltrated the skin and epidermal cells did not grow out of control. The findings highlight the potential of a natural product to safely treat psoriasis and related inflammatory disorders.

Two Promising Anti-Cancer Compounds, 2-Hydroxycinnaldehyde and 2-Benzoyloxycinnamaldehyde: Where do we stand?

Natural bioactive compounds with anti-carcinogenic activity are gaining tremendous interest in the field of oncology. Cinnamon, an aromatic condiment commonly used in tropical regions, appeared incredibly promising as adjuvant for cancer therapy. Indeed, its whole or active parts (e.g., bark, leaf) exhibited significant anti-carcinogenic activity, which is mainly due to two cinnamaldehyde derivatives, namely 2-hydroxycinnaldehyde (HCA) and 2-benzoyloxycinnamaldehyde (BCA). In addition to their anti-cancer activity, HCA and BCA exert immunomodulatory, anti-platelets, and anti-inflammatory activities. Highly reactive α,ß-unsaturated carbonyl pharmacophore, called Michael acceptor, contribute to their therapeutic effects. The molecular mechanisms, underlying their anti-tumoral and anti-metastatic effects are miscellaneous, strongly suggesting that these compounds are multi-targeting compounds. Nevertheless, unravelling the exact molecular mechanisms of HCA and BCA remain a challenging matter which is necessary for optimal controlled-drug targeting delivery, safety, and efficiency. Eventually, their poor pharmacological properties (e.g., systemic bioavailability and solubility) represent a limitation, and depend both on their administration route (e.g., per os, intravenously) and the nature of the formulation (e.g., free, smart nano-). This concise review focused on the potential of HCA and BCA as adjuvants in Cancer. We described their medicinal effects as well as provide an update about their molecular mechanisms reported either in-vitro, ex-vivo, or in animal models.

Synthesis of Novel Biocompatible Thienopyrimidine Chromophores with Aggregation-Induced Emission Sensitive to Molecular Aggregation

Biocompatible luminogens with aggregation-induced emission (AIE) have several applications in the biology field, such as in detecting biomacromolecules bioprobes and in bio-imaging. Due to their bioactivities and light-emitting properties, many heterocyclic compounds are good candidates for such applications. However, heterocyclic π-conjugated systems with AIE behavior remain rare as strong intermolecular π-π interactions usually quench their emission. In this work, new thienopyrimidine heterocyclic compounds were synthesized and their structures were verified by elemental analysis and Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (NMR), and 13C NMR spectra. The photophysical properties of some compounds were investigated in the solution and solid states. Density functional theory calculations were also performed to confirm the observed photophysical properties of the compounds. The studied dyes displayed AIE properties with spectral shapes related to the aggregate structure and a quantum yield up to 10.8%. The emission efficiency of the powder is attributed to the incorporation of multiply rotatable and twisted aryl groups to the fused heterocyclic moieties. The dyes also showed high thermal stability and potent antimicrobial activities against numerous bacterial and fungal strains. Additionally, the cytotoxicity of the new compounds was evaluated against the Caco-2 cell line, and molecular docking was used to investigate the binding conformation of the most effective compound with the MNK2 enzyme. Therefore, the presented structures may potentially be used for bioapplications.

MiR-381-3p suppresses biological characteristics of cancer in head-neck squamous cell carcinoma cells by targeting nuclear autoantigenic sperm protein (NASP)

MiR-381-3p and nuclear autoantigenic sperm protein (NASP) have regulatory functions in tumors. Whether NASP is targeted by miR-381-3p to influence biological characteristics of cancer in head-neck squamous cell carcinoma (HNSCC) cells was investigated. StarBase (version 3.0) found that the expression of NASP was increased with the down-regulation of miR-381-3p in laryngocarcinoma tissue, AMC-HN-3，FaDu，HNE-3，and Detroit 562 cell lines. MiR-381-3p could target NASP, reduce the expression of MMP-2 and MMP-9, Vimentin, repress the cell viability, invasion, and migration, and promote the expression of E-cadherin in AMC-HN-3 cells. Overexpressed NASP could increase the viability, migration and invasion rates in AMC-HN-3 cells, which could be partially reversed by overexpressed miR-381-3p. Thus, miR-381-3p targeted and suppressed NASP gene, reduced the viability, migration, invasion, EMT of HNSCC cells, demonstrating that miR-381-3p has the potential to be a therapeutic target in inhibiting the progression of HNSCC.

Development and validation of a bioanalytical HPLC method for simultaneous estimation of cinnamaldehyde and cinnamic acid in rat plasma: application for pharmacokinetic studies

A rapid, sensitive and accessible HPLC-UV method was developed and validated for simultaneous detection of CNAD and CA up to 1.0 ng ml⁻¹ in plasma samples.

Krüppel-like factors in breast cancer: Function, regulation and clinical relevance

Breast cancer has accounted for the leading cause of cancer-related mortality among women worldwide. Although the progress in its diagnosis and treatment has come at a remarkable pace during the past several decades, there are still a wide array of problems regarding its progression, metastasis and treatment resistance that have not yet been fully clarified. Recently, an increasing number of studies have revealed that some members of Krüppel-like factors(KLFs) are significantly associated with cell proliferation, apoptosis, metastasis, cancer stem cell regulation and prognostic and predictive value for patients in breast cancer, indicating their promising prognostic and predictive potential for breast cancer survival and outcome. In this review, we will summarize our current knowledge of the functions, regulations and clinical relevance of KLFs in breast cancer.

Anti-cancer effects of cinnamon: Insights into its apoptosis effects

Cancer is known as a leading cause of death worldwide. In the last two decades, the incidence of cancer has been dramatically increased mostly due to lifestyle changes. The importance of this issue has attracted further attention to discover novel therapies to prevent and treat cancers. According to previous studies, drugs used to treat cancer have shown significant limitations. Therefore, the role of herbal medicines alone or in combination with chemotherapy drugs has been extensively studied in cancer treatment. Cinnamon is a natural component showing a wide range of pharmacological functions including anti-oxidant, anti-microbial and anti-cancer activities. Impaired apoptosis plays critical roles in the initiation and progression of cancer. Increasing evidence indicates that cinnamon, as a therapeutic agent, has anti-cancer effects via affecting numerous apoptosis-related pathways in cancer cells. Here, we highlighted anticancer properties of cinnamon, particularly through targeting apoptosis-related mechanisms.

Combined treatment with 2'-hydroxycinnamaldehyde and temozolomide suppresses glioblastoma tumorspheres by decreasing stemness and invasiveness

INTRODUCTION

Glioblastoma (GBM) is the most common and aggressive human primary brain malignancy. The key properties of GBM, stemness and invasiveness, are known to be associated with a highly unfavorable prognosis. Notably, the process of epithelial-mesenchymal transition (EMT) is closely related to the progression of GBM. On the basis of reports that 2'-hydroxycinnamaldehyde (HCA) and its derivative, 2'-benzoyloxycinnamaldehyde (BCA), suppresses EMT in several human cancer cells, we sought to evaluate the therapeutic efficacy of HCA and BCA, alone and in combination with temozolomide (TMZ), on GBM tumorspheres (TSs).

METHODS

Two human GBM TSs were treated with HCA, BCA, or TMZ. Therapeutic effects were evaluated by measuring ATP levels, neurosphere formation, 3D-invasion in collagen matrix, and viability. Protein expression profiles after drug treatment were evaluated by western blotting. In vivo anticancer efficacy of drugs was examined in a mouse orthotopic xenograft model.

RESULTS

Combined treatment of GBM TSs with HCA or BCA and TMZ significantly reduced cell viability, stemness, and invasiveness. Expression levels of stemness-, invasiveness-, and mesenchymal transition-associated markers, Zeb1, N-cadherin, and β-catenin, were also substantially decreased by the combined treatment. The combined treatment also reduced tumor growth in a mouse orthotopic xenograft model.

CONCLUSION

Our findings suggest that HCA and BCA, combined with TMZ, are potential therapeutic agents in the treatment of GBM.

Can crude alkaloids extract of Rhazya stricta induce apoptosis in pancreatic cancer: In vitro study?

Cancer is a complicateddisease that reveals genetic variability even among the cells within the same tumor. Pancreatic cancer is the 12^th cause of cancer deaths over the world. As a result of the incomplete recovery and the many side effects of current clinical treatment approaches, Herbal diet therapy as a single or adjuvant therapy show high significant output in cancer treatment. Our study focused on the role of the crude alkaloid extract of Rhazya stricter (R. stricta) on pancreatic cancer cells using MTT assay. The cytotoxic effect of different concentrations of R. Strict crude alkaloid on the pancreatic cancer cells showed significant decrease in cell viability with dose dependent manner and the effect was observed at higher concentration of crude R. Stricta alkaloids. On the other hand, no significant cytotoxic effect was observed with the normal WISH cells at all R. Stricta crude alkaloid concentrations with IC50. Moving on, in AsPC-1cells under the same concentrations mRNA expression was increased by 1.5 and 6 folds with 10 and 100 μg/ Ml treatment when compared with control. Under the same experimental conditions, the anti- apoptotic marker Bcl-2 showed high significant decrease in mRNA expression in both PANC-1 and AsPC-1 pancreatic cancer cells. The present study indicated that the crude alkaloids extract of R. stricta significantly induce apoptotic cell death in pancreatic cancer cells.

Anticancer and Anti-Inflammatory Activities of Some New Pyrazolo[3,4-b]pyrazines

New derivatives of pyrazolo[3,4-b]pyrazines and related heterocycles were synthesized using 5-amino-3-methyl-4-nitroso-1-phenyl-pyrazole (1) as a starting material. The 5-acetyl derivative 15 was shown to be a useful key intermediate for the synthesis of several derivatives of pyrazolopyrazines. Some of the prepared compounds were evaluated for their anti-inflammatory and anti-breast cancer MCF-7 cell line activities. SAR study showed that compounds 15 and 29 exhibited remarkable anti-inflammatory activity, where 15 showed the same activity as that of the reference drug indomethacin. On the other hand, compounds 25i, 25j showed very significant inhibitory activity (p < 0.001) against MCF-7 breast cancer cell line.

Melatonin inhibits breast cancer cell invasion through modulating DJ-1/KLF17/ID-1 signaling pathway

Breast cancer is the most common neoplastic disorder diagnosed in women. The main goal of this study was to explore the effect of melatonin against breast cancer metastasis and compared this with the actions of taxol (a well-known chemotherapeutic drug), and the impact of their combination against breast cancer metastasis. Melatonin showed no cytotoxic effect while taxol showed antiproliferative and cytotoxic effects on MCF-7 and MDA-MB-231 cells. Furthermore, melatonin inhibited the generation of reactive oxygen species. Melatonin and taxol clearly decreased cell migration and invasion at low doses, especially those matching the normal physiological concentration at night. Melatonin and taxol markedly reduced DJ-1 and ID-1 and increased KLF17 messenger RNA and protein expression levels. The present results also showed that melatonin and taxol induced GSK3-β nuclear and Snail cytosolic localization. These changes were accompanied by a concurrent rise in E-cadherin expression. The above data show that normal levels of melatonin may help in preventing breast cancer metastasis through inhibiting DJ-1/KLF17/ID-1 signaling pathway. The combination of melatonin and taxol is a potent candidate against breast cancer metastasis, better than using melatonin or taxol as a single drug.

Low doses of Paclitaxel repress breast cancer invasion through DJ-1/KLF17 signalling pathway

Paclitaxel (taxol) is an important agent against many tumours, including breast cancer. Ample data documents that paclitaxel inhibits breast cancer metastasis while others prove that paclitaxel enhances breast cancer metastasis. The mechanisms by which paclitaxel exerts its action are not well established. This study focuses on the effect of paclitaxel, particularly the low doses on breast cancer metastasis and the mechanisms that regulate it. Current results show that, paclitaxel exerts significant cytotoxicity even at low doses in both MCF-7 and MDA-MB-231 cells. Interestingly, paclitaxel significantly inhibits cell invasion and migration, decreases Snail and increases E-cadherin mRNA expression levels at the indicated low doses. Furthermore, paclitaxel-inhibiting breast cancer metastasis is associated with down-regulation of DJ-1 and ID-1 mRNA expression level with a concurrent increase in KLF17 expression. Under the same experimental conditions, paclitaxel induces KLF17 and concurrently represses ID-1 protein levels. Our results show for the first time that paclitaxel inhibits breast cancer metastasis through regulating DJ-1/KLF17/ID-1 signalling pathway; repressed DJ-1 and ID-1 and enhanced KLF17 expression.

Targeting epithelial-mesenchymal plasticity in cancer: clinical and preclinical advances in therapy and monitoring

The concept of epithelial-mesenchymal plasticity (EMP), which describes the dynamic flux within the spectrum of phenotypic states that invasive carcinoma cells may reside, is being increasingly recognised for its role in cancer progression and therapy resistance. The myriad of events that are able to induce EMP, as well as the more recently characterised control loops, results in dynamic transitions of cancerous epithelial cells to more mesenchymal-like phenotypes through an epithelial-mesenchymal transition (EMT), as well as the reverse transition from mesenchymal phenotypes to an epithelial one. The significance of EMP, in its ability to drive local invasion, generate cancer stem cells and facilitate metastasis by the dissemination of circulating tumour cells (CTCs), highlights its importance as a targetable programme to combat cancer morbidity and mortality. The focus of this review is to consolidate the existing knowledge on the strategies currently in development to combat cancer progression via inhibition of specific facets of EMP. The prevalence of relapse due to therapy resistance and metastatic propensity that EMP endows should be considered when designing therapy regimes, and such therapies should synergise with existing chemotherapeutics to benefit efficacy. To further improve upon EMP-targeted therapies, it is imperative to devise monitoring strategies to assess the impact of such treatments on EMP-related phenomenon such as CTC burden, chemosensitivity/-resistance and micrometastasis in patients.

Cinnamaldehydes in Cancer Chemotherapy

Cinnamaldehyde and cinnamaldehyde-derived compounds are candidates for the development of anticancer drugs that have received extensive research attention. In this review, we summarize recent findings detailing the positive and negative aspects of cinnamaldehyde and its derivatives as potential anticancer drug candidates. Furthermore, we describe the in vivo pharmacokinetics and metabolism of cinnamaldehydes. The oxidative and antioxidative properties of cinnamaldehydes, which contribute to their potential in chemotherapy, have also been discussed. Moreover, the mechanism(s) by which cinnamaldehydes induce apoptosis in cancer cells have been explored. In addition, evidence of the regulatory effects of cinnamaldehydes on cancer cell invasion and metastasis has been described. Finally, the application of cinnamaldehydes in treating various types of cancer, including breast, prostate, and colon cancers, has been discussed in detail. The effects of cinnamaldehydes on leukemia, hepatocellular carcinoma, and oral cancer have been summarized briefly. Copyright © 2016 John Wiley & Sons, Ltd.

A Novel Cinnamon-Related Natural Product with Pim-1 Inhibitory Activity Inhibits Leukemia and Skin Cancer

The Pim-1 kinase regulates cell survival, proliferation, and differentiation and is overexpressed frequently in many malignancies, including leukemia and skin cancer. In this study, we used kinase profiling analysis to demonstrate that 2'-hydroxycinnamicaldehyde (2'-HCA), a compound found in cinnamon, specifically inhibits Pim-1 activity. Cocrystallography studies determined the hydrogen bonding pattern between 2'-HCA and Pim-1. Notably, 2'-HCA binding altered the apo kinase structure in a manner that shielded the ligand from solvent, thereby acting as a gatekeeper loop. Biologically, 2'-HCA inhibited the growth of human erythroleukemia or squamous epidermoid carcinoma cells by inducing apoptosis. The compound was also effective as a chemopreventive agent against EGF-mediated neoplastic transformation. Finally, 2'-HCA potently suppressed the growth of mouse xenografts representing human leukemia or skin cancer. Overall, our results offered preclinical proof of concept for 2'-HCA as a potent anticancer principle arising from direct targeting of the Pim-1 kinase.

Novel clinical therapeutics targeting the epithelial to mesenchymal transition

The epithelial to mesenchymal transition (EMT) is implicated in many processes, ranging from tissue and organogenesis to cancer and metastatic spread. Understanding the key regulatory mechanisms and mediators within this process offers the opportunity to develop novel therapeutics with broad clinical applicability. To date, several components of EMT already are targeted using pharmacologic agents in fibrosis and cancer. As our knowledge of EMT continues to grow, the potential for novel therapeutics will also increase. This review focuses on the role of EMT both as a necessary part of development and a key player in disease progression, specifically the similarity in pathways used during both processes as targets for drug development. Also, the key role of the tumor microenvironment with EMT is outlined, focusing on both co-factors and cell types with the ability to modulate the progression of EMT in cancer and metastatic disease. Lastly, we discuss the current status of clinical therapies both in development and those progressed to clinical trial specifically targeting pathologic EMTs including small molecule inhibitors, non-coding RNAs, exogenous co-factors, and adjunctive therapies to current chemotherapeutics.

Gain-of-function of mutant p53: mutant p53 enhances cancer progression by inhibiting KLF17 expression in invasive breast carcinoma cells

Kruppel-like-factor 17 (KLF17) is a negative regulator of metastasis and epithelial-mesenchymal-transition (EMT). However, its expression is downregulated in metastatic breast cancer that contains p53 mutations. Here, we show that mutant-p53 plays a key role to suppress KLF17 and thereby enhances cancer progression, which defines novel gain-of-function (GOF) of mutant-p53. Mutant-p53 interacts with KLF17 and antagonizes KLF17 mediated EMT genes transcription. Depletion of KLF17 promotes cell viability, decreases apoptosis and induces drug resistance in metastatic breast cancer cells. KLF17 suppresses cell migration and invasion by decreasing CD44, PAI-1 and Cyclin-D1 expressions. Taken together, our results show that KLF17 is important for the suppression of metastasis and could be a potential therapeutic target during chemotherapy.

Reduced Krüppel-like factor 17 (KLF17) expression correlates with poor survival in patients with gastric cancer

BACKGROUND AND AIMS

To investigate the expression and prognostic significance of Krüppel-like factor 17 (KLF17) in human gastric cancer.

METHODS

KLF17 expressions in 158 paraffin-embedded gastric cancer samples were analyzed using immunohistochemistry. In addition, KLF17 expressions patterns in three fresh gastric cancer tissues and noncancerous gastric mucosa were examined by Western blotting. The correlation between KLF17 expression and clinicopathological factors as well as patient survival was investigated.

RESULTS

Immunohistochemical staining data indicated that KLF17 expression was significantly decreased in 98 of 158 gastric adenocarcinoma cases. Reduced KLF17 expression in fresh gastric cancer tissues was confirmed by Western blotting. Reduced expression of KLF17 was strongly correlated with tumor size, pN stage and lymphovascular invasion. Multivariate Cox regression analysis identified KLF17 expression as an independent prognostic factor for both overall survival (HR = 0.481, 95% CI = 0.225-0.665, p = 0.009) and disease-free survival (HR = 0.438, 95% CI = 0.254-0.758, p = 0.003).

CONCLUSION

The reduced expression of KLF17 protein in gastric cancer was correlated with tumor size, pN stage and lymphovascular invasion and was an independent predictor for poor survival in patients undergoing surgery for gastric cancer.

LRP1-dependent pepsin clearance induced by 2'-hydroxycinnamaldehyde attenuates breast cancer cell invasion

2'-Hydroxycinnamaldehyde inhibits breast cancer cell invasion. This study examined whether 2'-hydroxycinnamaldehyde, acting as a Michael acceptor, interferes with the ligand binding of low-density lipoprotein receptor-related protein 1 to mediate breast cancer cell invasion. Low-density lipoprotein receptor-related protein 1, one of the direct molecular targets of 2'-hydroxycinnamaldehyde, is a multifunctional endocytic receptor. Changes in the thiol oxidation status of cell surface receptor proteins may function as a molecular switch, influencing ligand(s) binding. The oxidation status of extracellular cysteine thiol groups in MCF-7 and MDA-MB-231 cells was examined using a fluorescence-activated cell sorter with thiol-specific fluorescent probes; Matrigel invasion and wound-healing assays were performed to determine the effects of 2'-hydroxycinnamaldehyde on in vitro cell migration. The molecular mechanisms by which 2'-hydroxycinnamaldehyde acts were evaluated by transient knockdown using siRNA or inhibition of low-density lipoprotein receptor-related protein 1 by receptor-associated protein treatment. 2'-Hydroxycinnamaldehyde increased α-2-macroglobulin binding to low-density lipoprotein receptor-related protein 1, which was alleviated by pretreatment of cells with N-acetylcystein. 2'-Hydroxycinnamaldehyde decreased the extracellular pepsin concentration significantly in a low-density lipoprotein receptor-related protein 1- and α-2-macroglobulin-dependent manner. The anti-invasive effect of 2'-hydroxycinnamaldehyde was mitigated with receptor-associated protein pretreatment, suggesting that low-density lipoprotein receptor-related protein 1 is essential for the effects of 2'-hydroxycinnamaldehyde. From these data, we suggest that 2'-hydroxycinnamaldehyde increases the cysteine thiol oxidation status of low-density lipoprotein receptor-related protein 1 extracellular domains, which results in α-2-macroglobulin ligand binding stimulation. Therefore, pepsin clearance in a low-density lipoprotein receptor-related protein 1-α-2-macroglobulin-dependent manner might be an important molecular mechanism in 2'-hydroxycinnamaldehyde exerting its anti-invasive action on breast cancer cells. Furthermore, our data may provide an opportunity to promote the importance of the thiol oxidation status of cell surface receptor proteins for regulating cellular signaling pathways that are important in cancer progression.

EGR1-dependent PTEN upregulation by 2-benzoyloxycinnamaldehyde attenuates cell invasion and EMT in colon cancer

There has been little evidence to support EGR1 and PTEN function on the EMT of cancer cells. We tried to evaluate how these genes affect cancer cell invasion and EMT through investigating the molecular mechanism(s) of 2'-benzoyloxycinnamaldehyde (BCA). Matrigel invasion and wound healing assay, and in vivo mice model were used to evaluate the effect of BCA on colon cancer cell migration. The molecular mechanism(s) of BCA were evaluated by knock-down or overexpression of EGR1 and PTEN. BCA at 50 nM increased E-cadherin and EGR1 expression without cytotoxicity. Cell migration was inhibited significantly by BCA both in vitro and in vivo. Moreover, BCA inhibits Snail and Vimentin expression, as well as β-catenin nuclear accumulation. Suppression of EGR1 by siRNA attenuated the inhibition of matrigel invasion by BCA, indicating that EGR1 is responsible for BCA effect. PTEN was upregulated by BCA treatment or EGR1 overexpression. In addition, shPTEN transfection stimulated EMT and cell invasion in vitro. Our data suggest that BCA leads to a remarkable upregulation of EGR1 expression, and that EMT and invasion is decreased via EGR1-dependent PTEN activation. These data showed a critical role of EGR1-PTEN signaling pathway in the EMT of colon cancer, as well as metastasis.

Synthesis of metal nanoparticles inside living human cells based on the intracellular formation process

Intracellular and extracellular formation of Au and Ag NPs with different sizes and shapes using human cells has been developed as green method, which does not require the use of any reducing agents. Also, the cell lysis is used for production of different metal NPs. Our results demonstrate that treatment of human cells with various metal ions cause cell fixation.

Beta-elemene blocks epithelial-mesenchymal transition in human breast cancer cell line MCF-7 through Smad3-mediated down-regulation of nuclear transcription factors

Epithelial-mesenchymal transition (EMT) is the first step required for breast cancer to initiate metastasis. However, the potential of drugs to block and reverse the EMT process are not well explored. In the present study, we investigated the inhibitory effect of beta-elemene (ELE), an active component of a natural plant-derived anti-neoplastic agent in an established EMT model mediated by transforming growth factor-beta1 (TGF-β1). We found that ELE (40 µg/ml ) blocked the TGF-β1-induced phenotypic transition in the human breast cancer cell line MCF-7. ELE was able to inhibit TGF-β1-mediated upregulation of mRNA and protein expression of nuclear transcription factors (SNAI1, SNAI2, TWIST and SIP1), potentially through decreasing the expression and phosphorylation of Smad3, a central protein mediating the TGF-β1 signalling pathway. These findings suggest a potential therapeutic benefit of ELE in treating basal-like breast cancer.