2′-Benzoyloxycinnamaldehyde Induces Apoptosis in Human Carcinoma via Reactive Oxygen Species

Aberrant Methylation of Somatostatin Receptor 2 Gene Is Initiated in Aged Gastric Mucosa Infected with Helicobacter pylori and Consequential Gene Silencing Is Associated with Establishment of Inflammatory Microenvironment In Vitro Study

The loss-of-function variants are thought to be associated with inflammation in the stomach. We here aimed to evaluate the extent and role of methylation at the SSTR2 promoter in inflammation and gastric tumor formation. A whole-genome bisulfite sequencing analysis revealed that the SSTR2 promoter was significantly hypermethylated in gastric tumors, dysplasia, and intestinal metaplasia compared to non-tumor tissues from patients with gastric cancer. Using public data, we confirmed SSTR2 promoter methylation in primary gastric tumors and intestinal metaplasia, and even aged gastric mucosae infected with Helicobacter pylori, suggesting that aberrant methylation is initiated in normal gastric mucosa. The loss-of-function of SSTR2 in SNU638 cell-induced cell proliferation in vitro, while stable transfection of SSTR2 in AGS and MKN74 cells inhibited cell proliferation and tumorigenesis in vitro and in vivo. As revealed by a comparison of target genes differentially expressed in these cells with hallmark molecular signatures, inflammation-related pathways were distinctly induced in SSTR2-KO SNU638 cell. By contrast, inflammation-related pathways were inhibited in AGS and MKN74 cells ectopically expressing SSTR2. Collectively, we propose that SSTR2 silencing upon promoter methylation is initiated in aged gastric mucosae infected with H. pylori and promotes the establishment of an inflammatory microenvironment via the intrinsic pathway. These findings provide novel insights into the initiation of gastric carcinogenesis.

Targeting Redox Regulation as a Therapeutic Opportunity against Acute Leukemia: Pro-Oxidant Strategy or Antioxidant Approach?

Redox adaptation is essential for human health, as the physiological quantities of non-radical reactive oxygen species operate as the main second messengers to regulate normal redox reactions by controlling several sensors. An abnormal increase reactive oxygen species, called oxidative stress, induces biological injury. For this reason, variations in oxidative stress continue to receive consideration as a possible approach to treat leukemic diseases. However, the intricacy of redox reactions and their effects might be a relevant obstacle; consequently, and alongside approaches aimed at increasing oxidative stress in neoplastic cells, antioxidant strategies have also been suggested for the same purpose. The present review focuses on the molecular processes of anomalous oxidative stress in acute myeloid and acute lymphoblastic leukemias as well as on the oxidative stress-determined pathways implicated in leukemogenic development. Furthermore, we review the effect of chemotherapies on oxidative stress and the possibility that their pharmacological effects might be increased by modifying the intracellular redox equilibrium through a pro-oxidant approach or an antioxidant strategy. Finally, we evaluated the prospect of varying oxidative stress as an efficacious modality to destroy chemoresistant cells using new methodologies. Altering redox conditions may be advantageous for inhibiting genomic variability and the eradication of leukemic clones will promote the treatment of leukemic disease.

The Role of Bioactive Compounds from Dietary Spices in the Management of Metabolic Syndrome: An Overview

Metabolic syndrome (MetS) is a combination of physiologically dysregulated parameters that can include elevated fasting blood glucose, high blood pressure, central obesity, increased triglyceride levels, insulin resistance, diabetes, elevated low density lipoprotein levels, and reduced high density lipoprotein levels in the blood. Effective clinical management of MetS is critical as it is strongly associated with long lasting and fatal complications in patients. Alongside standard care of lifestyle changes and medication, dietary supplements derived from herbal resources could be an alternative therapeutic strategy that is safe, efficient, culturally acceptable, and has few side effects. Of the dietary supplements, spicy foods have always been considered a great source of functional bioactive compounds. Herbal therapy is broadly used in many countries as a treatment or as a preventive measure in the management of MetS risk factors, including blood glucose, blood pressure, and blood lipid levels. Herein, an attempt is made to evaluate the recent studies in the management of MetS with herbal alternatives, and to explore the possibility of their use as therapeutic treatments or supplements.

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.

Acacetin Inhibits the Growth of STAT3-Activated DU145 Prostate Cancer Cells by Directly Binding to Signal Transducer and Activator of Transcription 3 (STAT3)

Signal transducer and activator of transcription 3 (STAT3) plays a critical role in the formation and growth of human cancer. Therefore, STAT3 is a therapeutic target for cancer drug discovery. Acacetin, a flavone present in various plants, inhibits constitutive and inducible STAT3 activation in STAT3-activated DU145 prostate cancer cells. Acacetin inhibits STAT3 activity by directly binding to STAT3, which we confirmed by a pull-down assay with a biotinylated compound and two level-free methods, namely, a drug affinity responsive target stability (DARTS) experiment and a cellular thermal shift assay (CETSA). Acacetin inhibits STAT3 phosphorylation at the tyrosine 705 residue and nuclear translocation in DU145 cells, which leads to the downregulation of STAT3 target genes. Acacetin then induces apoptosis in a time-dependent manner. Interestingly, acacetin induces the production of reactive oxygen species (ROS) that are not involved in the acacetin-induced inhibition of STAT3 activation because the suppressed p-STAT3 level is not rescued by treatment with GSH or NAC, which are general ROS inhibitors. We also found that acacetin inhibits tumor growth in xenografted nude mice. These results suggest that acacetin, as a STAT3 inhibitor, could be a possible drug candidate for targeting STAT3 for the treatment of cancer in humans.

Recent developments in the medicinal chemistry of single boron atom-containing compounds

Various boron-containing drugs have been approved for clinical use over the past two decades, and more are currently in clinical trials. The increasing interest in boron-containing compounds is due to their unique binding properties to biological targets; for example, boron substitution can be used to modulate biological activity, pharmacokinetic properties, and drug resistance. In this perspective, we aim to comprehensively review the current status of boron compounds in drug discovery, focusing especially on progress from 2015 to December 2020. We classify these compounds into groups showing anticancer, antibacterial, antiviral, antiparasitic and other activities, and discuss the biological targets associated with each activity, as well as potential future developments.

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.

How the ascorbic acid and hesperidin do improve the biological activities of the cinnamon: theoretical investigation

DFT/B3LYP calculations have been performed on series of molecules of natural products containing cinnamon and citrus, namely, cinnamic aldehyd, ascorbic acid and hesperidin. This theoretical investigation predicts the biological activities of mixtures between cinnamon and ascorbic acid and between cinnamon and hesperidin based on already proven values for these molecules. The strength of the intermolecular interactions is evaluated in term of energy decomposition of the total interaction energy ΔE _int between molecules, which are mainly governed by electrostatic interactions. The HOMO-LUMO gaps explain that the possible charge transfer interactions that take place within the molecules are responsible for the molecular reactivity of the studied molecules. The chemical hardness, the chemical potential and the electrophilicity indexes are good indicators for biological activities showing their improvement to that of cinnamon itself. The mixture of hesperidin and cinnamon could be an excellent blood thinner with the regard to its polarity's enhancement.

Cascade of reactive oxygen species generation by polyprodrug for combinational photodynamic therapy

The redox status of cancer cells is well regulated by the balance between the reactive oxygen species (ROS) generation and elimination. Thus, the overall elevation of ROS level above the cellular tolerability threshold would lead to apoptotic or necrotic cell death. Herein, cinnamaldehyde (CA), a kind of oxidative stress amplified agent, was combined with photosensitizer pheophorbide A (PA) to promote the generation of ROS though synergistically endogenous and exogenous pathways. Firstly, acid-responsive polygalactose-co-polycinnamaldehyde polyprodrug (termed as PGCA) was synthesized, which could self-assemble into stable nanoparticles for the delivery of PA (termed as PGCA@PA NPs). The abundant expression of galactose receptor on tumor cells facilitated the positive targeting and cellular uptake efficiency of PGCA@PA NPs, after which PA could be synchronously released in company with the intracellular disassembly of PGCA NPs, due to the detaching of CA moieties under acidic microenvironment in endo/lysosomal compartment. Significantly increased ROS level was induced by the combined action of CA and PA with light irradiation, resulting in dramatically enhanced apoptosis of cancer cells. Importantly, intravenous injection of PGCA@PA NPs potently inhibited the tumor growth in hepatocellular carcinoma with negligible adverse effects. Moreover, combined with anti-programmed cell death protein 1 (anti-PD-1) therapy, PGCA@PA NPs treatment elicited anti-melanoma T-cell immune response and significantly promoted T cells infiltration in tumors. Hence, this novel polyprodrug nano delivery system was able to target and modulate the unique redox regulatory mechanisms of cancer cells through endogenous and exogenous pathways, providing a feasible approach to achieve synergetic therapeutic activity and selectivity.

Rational Design of Nanoparticles to Overcome Poor Tumor Penetration and Hypoxia-Induced Chemotherapy Resistance: Combination of Optimizing Size and Self-Inducing High Level of Reactive Oxygen Species

One tough question induced by the hypoxia in cancer tissue is resistance to anticancer drugs basing on the reactive oxygen species (ROS) mechanism. Furthermore, the hypoxic regions locate in the center of tumor where tumor cells are easily residual and survival due to the poor drug-delivery efficiency even with nanocarriers. In this paper, these problems were well addressed through the rational combination of the enhanced penetration, self-inducing high level of intracellular ROS, and synchronously pH-sensitive drug release, realized by a simple structural and accessible copolymer, poly(poly(ethylene glycol) methyl ether methacrylate-co-(2-methylpropenoic acid-glycerol-cinnamaldehyde)) (PgEMC). For one thing, PgEMC could self-assemble into stable nanoparticles with PEG shell and optimizing diameters of 60 nm to simultaneously facilitate long blood circulation and deep tumor penetration. Second, cinnamylaldehyde moieties could detach from PgEMC NPs in intracellular acidic environment and trigger high level of ROS to allay the doxorubicin (DOX) resistance induced by hypoxia in solid malignancies. Furthermore, the DOX payload in PgEMC NPs could be synchronously released with the intracellular disassembly of PgEMC NPs due to the detaching of cinnamylaldehyde moieties. In 4T1 cells treated with PgEMC/DOX NPs, remarkable elevation of ROS level and enhanced DOX sensitivity in hypoxia environment were observed in in vitro studies. The results of tumor spheroid penetration indicated that 60 nm sized DOX-loaded PgEMC NPs (PgEMC₆₀/DOX) could distribute into deep site of tumor at a high intensity. In vivo studies using a 4T1 breast tumor model, PgEMC₆₀/DOX NPs, showed significant inhibition over 95.4% of the tumor growth. These results reveal that integrating optimizing size, self-inducing ROS, and pH-sensitive drug release into one small-sized nanoparticle can efficiently overcome the poor tumor penetration and hypoxia-induced chemotherapy resistance.

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.

Carbon-dot-supported atomically dispersed gold as a mitochondrial oxidative stress amplifier for cancer treatment

Mitochondrial redox homeostasis, the balance between reactive oxygen species and antioxidants such as glutathione, plays critical roles in many biological processes, including biosynthesis and apoptosis, and thus is a potential target for cancer treatment. Here, we report a mitochondrial oxidative stress amplifier, MitoCAT-g, which consists of carbon-dot-supported atomically dispersed gold (CAT-g) with further surface modifications of triphenylphosphine and cinnamaldehyde. We find that the MitoCAT-g particles specifically target mitochondria and deplete mitochondrial glutathione with atomic economy, thus amplifying the reactive oxygen species damage caused by cinnamaldehyde and finally leading to apoptosis in cancer cells. We show that imaging-guided interventional injection of these particles potently inhibits tumour growth in subcutaneous and orthotopic patient-derived xenograft hepatocellular carcinoma models without adverse effects. Our study demonstrates that MitoCAT-g amplifies the oxidative stress in mitochondria and suppresses tumour growth in vivo, representing a promising agent for anticancer applications.

Modular synthesis of (E)-cinnamaldehydes directly from allylarenes via a metal-free DDQ-mediated oxidative process

An efficient synthesis of (E)-cinnamaldehydes by a metal-free DDQ-mediated oxidative transformation of allylarenes was developed. The protocol provides a practical method to prepare diverse (E)-cinnamaldehydes with broad functional group tolerance in good to excellent yields, including easy access to natural products randainal and geranyloxy sinapyl aldehyde from plant extracts. Finally, the mechanism of a single-electron transfer process was proposed.

2'-Hydroxycinnamaldehyde inhibits proliferation and induces apoptosis via signal transducer and activator of transcription 3 inactivation and reactive oxygen species generation

Inhibition of the signal transducer and activator of transcription 3 (STAT3) signaling pathway is a novel therapeutic strategy to treat human cancers with constitutively active STAT3. During the screening of natural products to find STAT3 inhibitors, we identified 2′‐hydroxycinnamaldehyde (HCA) as a STAT3 inhibitor, which was isolated from the stem bark of Cinnamomum cassia. In this study, we found that HCA inhibited constitutive and inducible STAT3 activation in STAT3‐activated DU145 prostate cancer cells. HCA selectively inhibited the STAT3 activity by direct binding to STAT3, which was confirmed by biochemical methods, including a pull‐down assay with biotin‐conjugated HCA, a drug affinity responsive target stability (DARTS) experiment and a cellular thermal shift assay (CETSA). HCA inhibited STAT3 phosphorylation at the tyrosine 705 residue, dimer formation, and nuclear translocation in DU145 cells, which led to a downregulation of STAT3 target genes. The downregulation of cell cycle progression and antiapoptosis‐related gene expression by HCA induced the accumulation of cells in the G0/G1 phase of the cell cycle and then induced apoptosis. We also found that reactive oxygen species (ROS) were involved in the HCA‐induced inhibition of STAT3 activation and cell proliferation because the suppressed p‐STAT3 level was rescued by glutathione or N‐acetyl‐L‐cysteine treatment, which are general ROS inhibitors. These results suggest that HCA could be a potent anticancer agent targeting STAT3‐activated tumor cells.

Novel cinnamaldehyde-based aspirin derivatives for the treatment of colorectal cancer

Colorectal cancer (CRC) is a leading cause of mortality worldwide. Current treatments of CRC involve anti-cancer agents with relatively good efficacy but unselectively target both cancer and non-cancer cells. Thus, there is a need to discover and develop novel CRC therapeutics that have potent anti-cancer effects, but show reduced off-target cell effects. Here, a novel series of cinnamaldehyde-based aspirin derivatives were designed and synthesized. Biological evaluation indicated that the most active compound 1f exhibited more than 10-fold increase in the anti-proliferation efficacy in HCT-8 cells compared to the parent compounds. Its effects were similarly reproduced in another CRC cell line, DLD-1, but with 7- to 11-fold less inhibitory activity in non-tumorigenic colon cells. Flow cytometry analysis showed that 1f induced cell cycle arrest and apoptosis, which was further validated with immunoblot analysis of the relative protein levels of cleaved caspase 3 and PARP as well as the ROS production in CRC cells. More so, 1f significantly inhibited the growth of implanted CRC in vivo in mouse xenograft model. Taken together, our results show that cinnamaldehyde-based aspirin derivatives such as 1f show promise as novel anti-CRC agent for further pharmaceutical development.

Isolation of anticancer and antimicrobial metabolites from Epicoccum nigrum; endophyte of Ferula sumbul

Owing to the importance of endophytes, current research was aimed to purify the secondary metabolites from targeted source. Ferula sumbul, a lipophilic extract of the endophyte was prepared in 10% methanol and partitioned with ethyl acetate and bioassay guided isolation was carried using standard protocols against bacterial, fungal and cancer cells. The active fractions consisted of three new metabolites (2-methyl-3-nonyl prodiginine, Bis (2-ethylhexyl) phthalate, and a meroterpenoid, Preaustinoid A). Their structures were confirmed with LCMS/MS. The purified metabolites showed valuable results against tested activities which concluded that these compounds have great potential and these may be applicable to textile (dyeing), pharmaceutical (drug, infectious agents) and food (preservatives) industries. This study reveals the potential of E. nigrum as an important source of bioactive compounds including 2-methyl-3-nonyl prodiginine, Bis (2-ethylhexyl) phthalate, and Preaustinoid A. This is first report of isolation of prodiginines as well as meroterpenoid and Bis (2-ethylhexyl) phthalate from Epicoccum nigrum.

2-Methoxycinnamaldehyde inhibits the TNF-α-induced proliferation and migration of human aortic smooth muscle cells

The abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) is a crucial event in the development of atherosclerosis, and tumor necrosis factor-α (TNF-α) is actively involved in this process by enhancing the proliferation and migration of VSMCs. 2-Methoxycinnamaldehyde (MCA) is a natural compound of Cinnamomum cassia. Although 2-hydroxycinnamaldehyde (HCA), another compound from Cinnamomum cassia, has been widely studied with regard to its antitumor activity, MCA has not attracted researchers' interest due to its mild toxic effects on cancer cells and its mechanisms of action remain unknown. In this study, we examined the effects of MCA on the TNF-α-induced proliferation and migration of human aortic smooth muscle cells (HASMCs). As shown by our results, MCA inhibited TNF-α-induced cell proliferation by reducing the levels of cyclin D1, cyclin D3, CDK4 and CDK6, and increasing the levels of the cyclin-dependent kinase inhibitors, p21 and p27, without resulting in cellular cytotoxicity. Furthermore, MCA decreased the level of secreted matrix metalloproteinase (MMP)-9 by inhibiting MMP-9 transcription. Unexpectedly, MCA did not affect the TNF-α-induced levels of mitogen-activated protein kinases (MAPKs). However, by showing that MCA potently inhibited the degradation of IκBα and the subsequent nuclear translocation of nuclear factor-κB (NF-κB), we demonstrated that MCA exerts its effects through the NF-κB signaling pathway. MCA also effectively inhibited platelet-derived growth factor (PDGF)-induced HASMC migration. Taken together, these observations suggest that MCA has the potential for use as an anti-atherosclerotic agent.

Nano-Fenton Reactors as a New Class of Oxidative Stress Amplifying Anticancer Therapeutic Agents

Cancer cells, compared to normal cells, are under oxidative stress associated with an elevated level of reactive oxygen species (ROS) and are more vulnerable to oxidative stress induced by ROS generating agents. Thus, manipulation of the ROS level provides a logical approach to kill cancer cells preferentially, without significant toxicity to normal cells, and great efforts have been dedicated to the development of strategies to induce cytotoxic oxidative stress for cancer treatment. Fenton reaction is an important biological reaction in which irons convert hydrogen peroxide (H2O2) to highly toxic hydroxyl radicals that escalate ROS stress. Here, we report Fenton reaction-performing polymer (PolyCAFe) micelles as a new class of ROS-manipulating anticancer therapeutic agents. Amphiphilic PolyCAFe incorporates H2O2-generating benzoyloxycinnamaldehyde and iron-containing compounds in its backbone and self-assembles to form micelles that serve as Nano-Fenton reactors to generate cytotoxic hydroxyl radicals, killing cancer cells preferentially. When intravenously injected, PolyCAFe micelles could accumulate in tumors preferentially to remarkably suppress tumor growth, without toxicity to normal tissues. This study demonstrates the tremendous translatable potential of Nano-Fenton reactors as a new class of anticancer drugs.

Vanadium compounds in medicine

Vanadium is a transition metal that, being ubiquitously distributed in soil, crude oil, water and air, also found roles in biological systems and is an essential element in most living beings. There are also several groups of organisms which accumulate vanadium, employing it in their biological processes. Vanadium being a biological relevant element, it is not surprising that many vanadium based therapeutic drugs have been proposed for the treatment of several types of diseases. Namely, vanadium compounds, in particular organic derivatives, have been proposed for the treatment of diabetes, of cancer and of diseases caused by parasites. In this work we review the medicinal applications proposed for vanadium compounds with particular emphasis on the more recent publications. In cells, partly due to the similarity of vanadate and phosphate, vanadium compounds activate numerous signaling pathways and transcription factors; this by itself potentiates application of vanadium-based therapeutics. Nevertheless, this non-specific bio-activity may also introduce several deleterious side effects as in addition, due to Fenton's type reactions or of the reaction with atmospheric O2, VCs may also generate reactive oxygen species, thereby introducing oxidative stress with consequences presently not well evaluated, particularly for long-term administration of vanadium to humans. Notwithstanding, the potential of vanadium compounds to treat type 2 diabetes is still an open question and therapies using vanadium compounds for e.g. antitumor and anti-parasitic related diseases remain promising.

The anticancer mechanism of 2'-hydroxycinnamaldehyde in human head and neck cancer cells

Cinnamaldehyde has been shown to effectively induce apoptosis in a number of human cancer cells. In the present study, cinnamaldehyde derivative-induced apoptosis and its signaling pathways were assessed in p53-wild (SGT) and p53-mutant (YD-10B) human head and neck cancer cells. The cinnamaldehyde derivatives, 2'-hydroxycinnamaldehyde (HCA) and 2'-benzoyloxycinnamaldehyde (BCA), exhibited powerful anti-proliferative effects on SGT and YD-10B cells. The apoptotic effect induced by HCA or BCA was supported by caspase-3, -7, -9 and PARP activation, and confirmed by Annexin V-FITC/PI double staining. HCA induced the expression of p21 in both SGT and YD-10B cells. Furthermore, HCA induced the level of pro-apoptotic Bak1 expression while decreasing the level of anti-apoptotic Bcl-2 in both cell lines, suggesting that HCA induced the cell death pathway in a p53-independent manner. HCA also induced the expression of LC3B in SGT and YD-10B cells. Following pre-incubation with the autophagy inhibitor 3-MA, HCA-induced apoptosis was largely increased in SGT cells, while inhibited in YD-10B cells, suggesting that autophagy may actively contribute to HCA-induced apoptosis. Taken together, these observations suggest that HCA may be an effective therapeutic agent in the treatment of head and neck cancer regardless of p53 status.

Cinnamon: Mystic powers of a minute ingredient

Cinnamon, due to its exotic flavor and aroma, is a key ingredient in the kitchen of every household. From the beginning of its use in 2800 BC by our ancestors for various purposes such as anointment, embalming and various ailments, it has instigated the interest of many researchers. Recently many trials have explored the beneficial effects of cinnamon in Parkinsons, diabetes, blood, and brain. After extensive research on PubMed and Google scholar, data were collected regarding its antioxidant, anti-inflammatory, antilipemic, antidiabetic, antimicrobial, and anticancer effect. This systematic review underlines the surplus health benefits of this clandestine ingredient and the scope of further research in these clinical scenarios.

Hydrogen peroxide-responsive anticancer hyperbranched polymer micelles for enhanced cell apoptosis

Hydrogen peroxide-responsive nanomicelles from hyperbranched polymers were developed for effective cancer therapy through enhanced apoptotic cell death.

Aryl-acetic and cinnamic acids as lipoxygenase inhibitors with antioxidant, anti-inflammatory, and anticancer activity

Cinnamic acids have been identified as interesting compounds with cytotoxic, anti-inflammatory, and antioxidant properties. Lipoxygenase pathway, catalyzing the first two steps of the transformation of arachidonic acid into leukotrienes is implicated in several processes such as cell differentiation, inflammation and carcinogenesis. Development of drugs that interfere with the formation or effects of these metabolites would be important for the treatment of various diseases like asthma, psoriasis, ulcerative colitis, rheumatoid arthritis, atherosclerosis, cancer, and blood vessel disorders. Till now, asthma consists of the only pathological case in which improvement has been shown by lipoxygenase LO inhibitors. Thus, the research has been directed towards the development of drugs that interfere with the formation of leukotrienes. In order to explore the anti-inflammatory and cytotoxic effects of antioxidant acrylic/cinnamic acids a series of derivatives bearing the appropriate moieties have been synthesized via the Knoevenagel condensation and evaluated for their biological activities. The compounds have shown important antioxidant activity, anti-inflammatory activity and very good inhibition of soybean lipoxygenase while some of them were tested for their anticancer activity.

Novel cinnamic acid derivatives as antioxidant and anticancer agents: design, synthesis and modeling studies

Cinnamic acids have been identified as interesting compounds with antioxidant, anti-inflammatory and cytotoxic properties. In the present study, simple cinnamic acids were synthesized by Knoevenagel condensation reactions and evaluated for the above biological activities. Compound 4ii proved to be the most potent LOX inhibitor. Phenyl- substituted acids showed better inhibitory activity against soybean LOX, and it must be noted that compounds 4i and 3i with higher lipophilicity values resulted less active than compounds 2i and 1i. The compounds have shown very good activity in different antioxidant assays. The antitumor properties of these derivatives have been assessed by their 1/IC50 inhibitory values in the proliferation of HT-29, A-549, OAW-42, MDA-MB-231, HeLa and MRC-5 normal cell lines. The compounds presented low antitumor activity considering the IC50 values attained for the cell lines, with the exception of compound 4ii. Molecular docking studies were carried out on cinnamic acid derivative 4ii and were found to be in accordance with our experimental biological results.

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.

Early growth response protein 1 upregulation and nuclear translocation by 2'-benzoyloxycinnamaldehyde induces prostate cancer cell death

2'-Benzoyloxycinnamaldehyde (BCA) induces apoptosis in human cancer cells through ROS generation. BCA upregulates proapoptotic genes such as activating transcription factor 3 (ATF3), NSAID-activated gene 1 protein (NAG-1), and growth arrest and DNA-damage-inducible protein alpha (GADD45A) in prostate cancer cells. These genes are known to be induced by transcription factor early growth response protein 1 (EGR1). BCA induces significant EGR1 upregulation, while EGR1 knockdown decreases the induction of these genes with concurrent alleviation of cell death by BCA. Antioxidant glutathione pretreatment with BCA removes EGR1 expression increase, suggesting that EGR1 upregulation is dependent on oxidative stress generated by BCA. In prostate cancer cells, EGR1 localizes in the cytoplasm; however, BCA remarkably upregulates EGR1 nuclear translocalization, suggesting its possible effect as a transcriptional activator. BCA induces transient upregulation of importin-7 (IPO7) which is critical for EGR1 nuclear translocation, and IPO7 knockdown led to a significant decrease in chemosensitivity to BCA. Taken together, our findings suggest that BCA induces prostate cancer cell death via EGR1 upregulation and nuclear translocalization, followed by activation of proapoptotic target genes.

Induction of tumor cell death through targeting tubulin and evoking dysregulation of cell cycle regulatory proteins by multifunctional cinnamaldehydes

Multifunctional trans-cinnamaldehyde (CA) and its analogs display anti-cancer properties, with 2-benzoyloxycinnamaldehyde (BCA) and 5-fluoro-2-hydroxycinnamaldehyde (FHCA) being identified as the ortho-substituted analogs that possess potent anti-tumor activities. In this study, BCA, FHCA and a novel analog 5-fluoro-2-benzoyloxycinnamaldehyde (FBCA), were demonstrated to decrease growth and colony formation of human colon-derived HCT 116 and mammary-derived MCF-7 carcinoma cells under non-adhesive conditions. The 2-benzoyloxy and 5-fluoro substituents rendered FBCA more potent than BCA and equipotent to FHCA. The cellular events by which these cinnamaldehydes caused G(2)/M phase arrest and halted proliferation of HCT 116 cells were thereby investigated. Lack of significant accumulation of mitosis marker phospho-histone H3 in cinnamaldehyde-treated cells indicated that the analogs arrested cells in G(2) phase. G(2) arrest was brought about partly by cinnamaldehyde-mediated depletion of cell cycle proteins involved in regulating G(2) to M transition and spindle assembly, namely cdk1, cdc25C, mad2, cdc20 and survivin. Cyclin B1 levels were found to be increased, which in the absence of active cdk1, would fail to drive cells into M phase. Concentrations of cinnamaldehydes that brought about dysregulation of levels of cell cycle proteins also caused tubulin aggregation, as evident from immunodetection of dose-dependent tubulin accumulation in the insoluble cell lysate fractions. In a cell-free system, reduced biotin-conjugated iodoacetamide (BIAM) labeling of tubulin protein pretreated with cinnamaldehydes was indicative of drug interaction with the sulfhydryl groups in tubulin. In conclusion, cinnamaldehydes treatment at proapoptotic concentrations caused tubulin aggregation and dysegulation of cell cycle regulatory proteins cdk1 and cdc25C that contributed at least in part to arresting cells at G(2) phase, resulting in apoptotic cell death characterized by emergence of cleaved forms of caspase 3 and poly (ADP-ribose) polymerase (PARP). Results presented in this study have thus provided further insights into the intricate network of cellular events by which cinnamaldehydes induce tumor cell death.

2'-Benzoyloxycinnamaldehyde-mediated DJ-1 upregulation protects MCF-7 cells from mitochondrial damage

2'-Benzoyloxycinnamaldehyde (BCA) is a promising antitumor agent which induces cancer cells apoptosis via reactive oxygen species (ROS) generation. BCA shows more effective antiproliferation in MDA-MB-435 than in MCF-7 breast cancer cells. DJ-1 has been known to protect cells against oxidative stress as an antioxidant because of its cysteine residues sensitive to oxidative stress. In the present study, we evaluated the mechanism of DJ-1 for cell protection from oxidative stress after BCA treatment in MCF-7 cell. BCA upregulates the expression of DJ-1 in MCF-7 cells. However, DJ-1 expression decreased continuously for 24 h after BCA treatment in MDA-MB-435 cells. DJ-1 knockdown sensitized MCF-7 cells to BCA, on the contrary, DJ-1 overexpression induced MDA-MB-435 cells less sensitive to BCA. Confocal microscopic observation showed that only in MCF-7 cells BCA increased the overlapped signal between mitochondria and DJ-1 protein. Mitochondrial membrane potential (MMP) was decreased in MDA-MB-435 cells by BCA, and DJ-1 overexpression inhibited BCA-induced MMP decrease in these cells. On the contrary, DJ-1 knockdown in MCF-7 induced MMP perturbation by BCA. These findings suggest that DJ-1 upregulation protects MCF-7 cells from BCA via inhibiting mitochondrial damage.

Chemoprevention against hepatocellular carcinoma

Since the majority of hepatocellular carcinoma (HCC) arises from a background of chronic liver diseases caused by infection with hepatitis C virus (HCV) and hepatitis B virus (HBV), chemoprevention targeting patients at high risk of HCC is feasible. In this review article, we summarize current knowledge of chemoprevention against HCC mostly using phytochemicals which have less toxicity than pharmaceutical agents. We describe in vivo and in vitro evidence and proposed mechanisms of beneficial effects of several compounds on the liver, including acyclic retinoid (ACR), angiotensin-converting enzyme inhibitors (ACEIs), caffeine, capsaicin, cepharanthine (CEP), cinnamaldehyde, curcumin, diallyl sulfide (DAS), eicosapentaenoic acid (EPA), epigallocatechin-3-gallate (EGCG), genistein, lycopene, resveratrol, silymarin, sulforaphane (SFN), and xanthohumol (XN). Because antihepatocarcinogenic effects by these compounds are mostly based on experimental studies, clinical evidence is urgently necessary.

Exceptional production of both prodigiosin and cycloprodigiosin as major metabolic constituents by a novel marine bacterium, Zooshikella rubidus S1-1

A Gram-negative, red-pigment-producing marine bacterial strain, designated S1-1, was isolated from the tidal flat sediment of the Yellow Sea, Korea. On the basis of phenotypic, phylogenetic, and genetic data, strain S1-1 (KCTC 11448BP) represented a new species of the genus Zooshikella. Thus, we propose the name Zooshikella rubidus sp. nov. Liquid chromatography and mass spectrometry of the red pigments produced by strain S1-1 revealed that the major metabolic compounds were prodigiosin and cycloprodigiosin. In addition, this organism produced six minor prodigiosin analogues, including two new structures that were previously unknown. To our knowledge, this is the first description of a microorganism that simultaneously produces prodigiosin and cycloprodigiosin as two major metabolites. Both prodigiosin and cycloprodigiosin showed antimicrobial activity against several microbial species. These bacteria were approximately 1.5-fold more sensitive to cycloprodigiosin than to prodigiosin. The metabolites also showed anticancer activity against human melanoma cells, which showed significantly more sensitivity to prodigiosin than to cycloprodigiosin. The secondary metabolite profiles of strain S1-1 and two reference bacterial strains were compared by liquid chromatography-mass spectrometry. Multivariate statistical analyses based on secondary metabolite profiles by liquid chromatography-mass spectrometry indicated that the metabolite profile of strain S1-1 could clearly be distinguished from those of two phylogenetically related, prodigiosin-producing bacterial strains.

2-Hydroxycurcuminoid induces apoptosis of human tumor cells through the reactive oxygen species-mitochondria pathway

2-Hydroxycinnamaldehyde (HCA) and curcumin have been reported to have antitumor effects against various human tumor cells in vitro and in vivo by generation of ROS. Aldehyde-free HCA analogs were synthesized based on the structure of curcumin, which we have called 2-hydroxycurcuminoids. The hydroxyl group of curcuminoids enhances the ability to generate ROS. 2-Hydroxycurcuminoid (HCC-7) strongly inhibited the growth of SW620 colon tumor cells with a GI(50) value of 7μM, while the parent compounds, HCA and curcumin, displayed GI(50) values of 12 and 30μM, respectively. HCC-7 was found to induce apoptosis through the reactive oxygen species-mitochondria pathway and cell cycle arrest at G2/M phase.