Xanthohumol induces apoptosis and S phase cell cycle arrest in A549 non-small cell lung cancer cells

Polyphenols as Therapeutics in Respiratory Diseases: Moving from Preclinical Evidence to Potential Clinical Applications

Respiratory diseases are the most common and severe health complication and a leading cause of death worldwide. Despite breakthroughs in diagnosis and treatment, few safe and effective therapeutics have been reported. Phytochemicals are gaining popularity due to their beneficial effects and low toxicity. Polyphenols are secondary metabolites with high molecular weights found at high levels in natural food sources such as fruits, vegetables, grains, and citrus seeds. Over recent decades, polyphenols and their beneficial effects on human health have been the subject of intense research, with notable successes in preventing major chronic non-communicable diseases. Many respiratory syndromes can be treated effectively with polyphenolic supplements, including acute lung damage, pulmonary fibrosis, asthma, pulmonary hypertension, and lung cancer. This review summarizes the role of polyphenols in respiratory conditions with sufficient experimental data, highlights polyphenols with beneficial effects for each, and identifies those with therapeutic potential and their underlying mechanisms. Moreover, clinical studies and future research opportunities in this area are discussed.

Xanthohumol, a prenylated flavonoid from hops (Humulus lupulus L.) exerts multidirectional pro-healing properties towards damaged zebrafish hair cells by regulating the innate immune response

Xanthohumol (XN) is a prominent prenylated flavonoid present in the hop plant (Humulus lupulus L.). Despite undoubted pro-healing properties of hop plant, there is still a need for clinical investigations confirming these effects as well as the underlying molecular mechanisms. The present study was designed to (1) establish the role of XN in non-invasive inflammation induced by chemical damage to zebrafish hair cells, (2) clarify if it influences cell injury severity, neutrophil migration, macrophage activation, cell regeneration, and (3) find out whether it modulates the gene expression profile of chosen immune and stress response markers. All experiments were performed on 3 dpf zebrafish larvae. After fertilization the embryos were transferred to appropriate XN solutions (0.1 μM, 0.3 μM and 0.5 μM). The 40 min 10 μM CuSO4 exposure evoked severe damage to posterior lateral line hair cells triggering a robust acute inflammatory response. Four readouts were selected as the indicators of XN role in the process of inflammation: 1) hair cell death, 2) neutrophil migration towards damaged hair cells, 3) macrophage activation and recruitment to damaged hair cells, 4) hair cell regeneration. The assessments involved in vivo confocal microscopy imaging and qPCR based molecular analysis. It was demonstrated that XN (1) influences death pathway of damaged hair cells by redirecting their severe necrotic phenotype into apoptotic one, (2) impacts the immune response via regulating neutrophil migration, macrophage recruitment and activation (3) modulates gene expression of immune system markers and (4) accelerates hair cell regeneration.

The Antiproliferative Effect of Chloroform Fraction of Eleutherine bulbosa (Mill.) Urb. on 2D- and 3D-Human Lung Cancer Cells (A549) Model

Since lung cancer is the leading cause of cancer-related death worldwide, research is being conducted to discover anticancer agents as its treatment. Eleutherine bulbosa, a Dayak folklore medicine, exhibited anticancer effects against several cancer cells; however, its anticancer potency against lung cancer cells has not been explored yet. This study aims to determine the anticancer potency of E. bulbosa bulbs against lung cancer cells (A549) using 2D and 3D culture models, as well as determine its active compounds using gas chromatography-mass spectrometry (GC-MS) analysis. Three fractions of E. bulbosa bulbs, namely chloroform, n-hexane, and ethyl acetate, were tested for cytotoxicity using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide (MTT) and CellTiter-Glo. The antiproliferative effects of the most cytotoxic fraction against the 2D culture model were determined by a clonogenic survival assay and propidium iodide/Hoechst 33342 double staining, whereas the effects against the 3D culture model were determined by microscopy, flow cytometry, and gene expression analysis. The chloroform fraction is the most cytotoxic against A549 cells than other fractions, and it inhibited colony formation and induced apoptosis of A549 cells. The chloroform fraction also inhibited the growth of the A549 spheroid by suppressing the spheroid size, inducing apoptosis, reducing the proportion of CD44 lung cancer stem cells, causing arrest at the S phase of the cell cycle, and suppressing the expression of the SOX2 and MYC genes. Furthermore, the GC-MS analysis detected 20 active compounds in the chloroform fraction, including the major compounds of eleutherine and isoeleutherine. In conclusion, the chloroform fraction of E. bulbosa bulbs exhibit its antiproliferative effect on 2D and 3D culture models of A549 cells, suggesting it could be a lung cancer chemopreventive agent.

Anticancer Potential of Natural Chalcones: In Vitro and In Vivo Evidence

There is no doubt that significant progress has been made in tumor therapy in the past decades. However, the discovery of new molecules with potential antitumor properties still remains one of the most significant challenges in the field of anticancer therapy. Nature, especially plants, is a rich source of phytochemicals with pleiotropic biological activities. Among a plethora of phytochemicals, chalcones, the bioprecursors of flavonoid and isoflavonoids synthesis in higher plants, have attracted attention due to the broad spectrum of biological activities with potential clinical applications. Regarding the antiproliferative and anticancer effects of chalcones, multiple mechanisms of action including cell cycle arrest, induction of different forms of cell death and modulation of various signaling pathways have been documented. This review summarizes current knowledge related to mechanisms of antiproliferative and anticancer effects of natural chalcones in different types of malignancies including breast cancers, cancers of the gastrointestinal tract, lung cancers, renal and bladder cancers, and melanoma.

QSAR-driven synthesis of antiproliferative chalcones against SH-SY5Y cancer cells: Design, biological evaluation, and redesign

Neuroblastoma is one of the most frequent types of cancer found in infants, and traditional chemotherapy has limited efficacy against this pathology. Thus, the development of new compounds with higher activity and selectivity than traditional drugs is a current challenge in medicinal chemistry research. In this study, we report the synthesis of 21 chalcones with antiproliferative activity and selectivity against the neuroblastoma cell line SH-SY5Y. Then, we developed three-dimensional quantitative structure-activity relationship models (comparative molecular field analysis and comparative molecular similarity index analysis) with high-quality statistical values (q²  > 0.7; r²  > 0.8; r² _pred  > 0.7), using IC₅₀ and selectivity index (SI) data as dependent variables. With the information derived from these theoretical models, we designed and synthesized 16 new molecules to prove their consistency, finding good antiproliferative activity against SH-SY5Y cells on these derivatives, with three of them showing higher SI than the referential drugs 5-fluorouracil and cisplatin, displaying also a proapoptotic effect comparable to these drugs, as proven by measuring their effects on executor caspases 3/7 activity induction, Bcl-2/Bax messenger RNA levels alteration, and DNA fragmentation promotion.

Antioxidants in Hops: Bioavailability, Health Effects and Perspectives for New Products

Hop plant (Humulus lupulus L.) has been used by humans for ages, presumably first as a herbal remedy, then in the manufacturing of different products, from which beer is the most largely consumed. Female hops cones have different useful chemical compounds, an important class being antioxidants, mainly polyphenols. This narrative review describes the main antioxidants in hops, their bioavailability and biological effects, and the results obtained by now in the primary and secondary prevention of several non-communicable diseases, such as the metabolic syndrome related diseases and oncology. This article presents in vitro and in vivo data in order to better understand what was accomplished in terms of knowledge and practice, and what needs to be clarified by additional studies, mainly regarding xantohumol and its derivates, as well as regarding the bitter acids of hops. The multiple protective effects found by different studies are hindered up to now by the low bioavailability of some of the main antioxidants in hops. However, there are new promising products with important health effects and perspectives of use as food supplements, in a market where consumers increasingly search for products originating directly from plants.

Xanthohumol reduces inflammation and cell metabolism in HT29 primary colon cancer cells

Xanthohumol (XN) is a prenylated flavonoid known for its antioxidant and anti-inflammatory effects and has been studied as an anti-cancer agent. In this study, we aimed at analysing the effect of XN on a primary colorectal adenocarcinoma cell line, HT29, on cell viability, inflammatory and antioxidant gene expression, and metabolism. For this purpose, cells were treated with 10 nM and 10 µM XN, and cell viability, H₂O₂ production, lipid peroxidation and gene expression of inflammatory, antioxidant, and mitochondrial-related genes, as well as protein levels of metabolic enzymes, were determined. Results showed no significant effects on cell viability and a general decrease in pro-inflammatory, antioxidant and mitochondrial biogenesis gene expression with the lower concentration of XN. Furthermore, glucose and oxidative metabolism enzymes were also reduced. These results suggest that XN treatment, at low doses, could stop the proliferation and progression of HT29 cells by downregulating inflammatory signals and cell metabolism.

Azide-mediated unusual in situ transformation of Mannich base to Schiff-Mannich base and isolation of their Cu(II) complexes: crystal structure, theoretical inspection and anticancer activities

A new "end-off" compartmental Mannich ligand (HL1) namely 3-((bis(2-methoxyethyl)amino)methyl)-5-bromo-2-hydroxybenzaldehyde containing two methoxyethyl pendant arms and one-CHO functionality has been synthesized through conventional C-C and C-N coupling reactions. On treatment with Cu(ClO₄)₂, HL1 yields a dinuclear μ-phenolatocopper(II) complex having the molecular formula [Cu₂(L¹)₂](ClO₄)₂(H₂O)_1.5 (1). Surprisingly, the ligand HL1 is radically transformed into a new asymmetric Schiff-Mannich base ligand (HLF) in the presence of NaN₃ and Cu(ClO₄)₂ forming a unique dinuclear centro-symmetric Cu(II) complex [Cu(L^F)]₂ (2) as evident from single-crystal X-ray diffraction (SCXRD) analysis. A probable mechanistic rationalization has been proposed on the basis of theoretical calculations, which suggests systematic fragmentation of HL1 in the presence of azide residue and re-condensation of the fragmented units to yield the final Cu-HL^F complex (2). SCXRD analysis portrays a large inter-metallic distance in complex 2 in comparison with complex 1 (5.493 vs. 2.989 Å, respectively) along with other distinct structural features. After physicochemical characterization both the complexes have been exploited to evaluate their possible anticancer proficiency on lung adenocarcinoma cell line (A549). Complex 1 distinctly impeded the proliferation of lung adenocarcinoma cells in a dose-dependent manner more efficiently than complex 2. Due to the behavior of complex 1 as potential therapeutics, cellular transformations of A549 cells have been systematically investigated. As evidenced from various in vitro experiments, the cell death mechanism triggered by complex 1 turned out to be apoptosis, as indicated by the DNA fragmentation, chromatin condensation, membrane blebbing and imbalanced cell cycle distribution as well as retard migration in A549 cells.

Xanthohumol from Hop: Hope for cancer prevention and treatment

Cancer is a major public health concern due to high mortality and poor quality of life of patients. Despite the availability of advanced therapeutic interventions, most treatment modalities are not efficacious, very expensive, and cause several adverse side effects. The factors such as drug resistance, lack of specificity, and low efficacy of the cancer drugs necessitate developing alternative strategies for the prevention and treatment of this disease. Xanthohumol (XN), a prenylated chalcone present in Hop (Humulus lupulus), has been found to possess prominent activities against aging, diabetes, inflammation, microbial infection, and cancer. Thus, this manuscript thoroughly reviews the literature on the anti-cancer properties of XN and its various molecular targets. XN was found to exert its inhibitory effect on the growth and proliferation of cancer cells via modulation of multiple signaling pathways such as Akt, AMPK, ERK, IGFBP2, NF-κB, and STAT3, and also modulates various proteins such as Notch1, caspases, MMPs, Bcl-2, cyclin D1, oxidative stress markers, tumor-suppressor proteins, and miRNAs. Thus, these reports suggest that XN possesses enormous therapeutic potential against various cancers and could be potentially used as a multi-targeted anti-cancer agent with minimal adverse effects.

(+)-Usnic acid modulates the Nrf2-ARE pathway in FaDu hypopharyngeal carcinoma cells

Naturally occurring phytochemicals of different origin and structure, arctigenin, bergenin, usnic acid and xanthohumol, were shown to affect Nrf2 pathway in the context of various diseases, but their effect on this pathway in cancer cells was not extensively investigated. This study aimed to evaluate the effect of these compounds on Nrf2 expression and activation in hypopharyngeal FaDu squamous cell carcinoma cells. FaDu cells were treated with 2 or 10 μM arctigenin, bergenin, (+)-usnic acid or xanthohumol for 24 h. While arctigenin, bergenin, and xanthohumol did not affect either Nrf2 expression or activation, (+)-usnic acid treatment increased its transcript level and increased the nuclear/cytosol Nrf2 protein ratio—the measure of Nrf2 pathway activation. Consequently, (+)-usnic acid enhanced the transcription and translation of Nrf2 target genes: NQO1, SOD, and to a lesser extent, GSTP. The treatment of FaDu cells with (+)-usnic acid decreased both GSK-3β transcript and protein level, indicating its possible involvement in Nrf2 activation. All the tested compounds decreased Bax mRNA but did not change the level of Bax protein. (+)-Usnic acid tended to increase the percentage of early apoptotic cells and LC3 protein, autophagy marker. Significant induction of p53 also was observed after treatment with (+)-usnic acid. In summary, the results of this study indicate that low concentrations of (+)-usnic acid activate Nrf2 transcription factor, most probably as a result of ROS accumulation, but do not lead to FaDu hypopharyngeal carcinoma cells death.

EZH2-TROAP Pathway Promotes Prostate Cancer Progression Via TWIST Signals

Trophinin-associated protein (TROAP) has been shown to be overexpressed and promotes tumor progression in some tumors. We performed this study to assess the biological and clinical significance of TROAP in prostate cancer. We downloaded TROAP mRNA expression data from TCGA and GEO databases. We analyzed expressions of TROAP and other genes in prostate cancer tumors at different stages and assessed Gleason scores. We used Celigo image, Transwell, and rescue assays, and flow cytometry detection to assess growth, apoptosis, proliferation, migration, and invasion of the prostate cancer cells. We identified and validated up- and down-stream genes in the TROAP pathway. The mRNA data suggested that TROAP expression was markedly upregulated in prostate cancer compared with its expression in normal tissues, especially in cancers with high stages and Gleason scores. Moreover, a high TROAP expression was associated with poor patient survival. Results of our in vitro assay showed that TROAP knockdown inhibited DU145 and PC3 cell proliferation and viability via cell apoptosis and S phase cycle arrest. The Transwell assay showed that TROAP knockdown inhibited cell migration and invasion, probably through MMP-9 and E-Cadherin modulation. Overexpression of TWIST partially abrogated the inhibitory effects of TROAP knockdown on prostate cancer cells. Our integrative mechanism dissection revealed that TROAP is in a pathway downstream of EZH2 and that it activates the TWIST/c-Myc pathway to regulate prostate cancer progression. In all, we identified TROAP as a driver of prostate cancer development and progression, providing a novel target for prostate cancer treatments.

Xanthohumol: A Metabolite with Promising Anti-Neoplastic Potential

The overwhelming globalburden of cancer has posed numerous challenges and opportunities for developing anti-cancer therapies. Phytochemicalshave emerged as promising synergistic compounds with potential anti-cancer effects to supplement chemo- and immune-therapeutic regimens. Anti cancer synergistic effects have been investigated in the interaction between phytocompounds derived from flavonoids such as quercetin, apigenin, kaempferol, hesperidin, emodin etc., and conventional drugs. Xanthohumol is one of the prenylatedphytoflavonoid that has demonstrated key anti-cancer activities in in vitro (anti proliferation of cancer cell lines) and in vivo(animal models of xenograft tumours)studies, and has been explored from different dimensions for targeting cancer subtypes. In the last decade, xanthohumol has been investigated how it induces the anti-cancer effects at cellular and molecular level.The different signalling cascades and targets of xanthohumolare summarized in thisreview.Overall, this reviewsummarizes the current advances made in the field of natural compounds with special reference to xanthohumol and its promising anti-cancer effectsto inhibit tumour progression.The present review hasalso touched upon the potential of xanthohumol transitioning into a lead candidate from nano-therapy viewpoint along with the challenges which need to be addressed for extensive pre-clinical and clinical anti-cancer studies.

Prenylated flavonoids in foods and their applications on cancer prevention

Functional foods play an important role in health care and chronic diseases prevention, particularly cancer. Prenylated flavonoids are presented in many food resources. They are recognized as neutraceuticals due to their diverse health benefits. Up to now, more than 1000 prenylated flavonoids have been identified in plants. Their food resources are reviewed in this paper. Due to the good safety and cancer prevention effect of prenylated flavonoids, this paper reviews the cancer prevention activities and mechanisms reported in last decade. The structure-activity relationship is discussed. Due to the limited availability in nature, the heterologously biosynthetic technique of prenylated flavonoids is discussed in this review. Inclusion of dietary prenylated flavonoids into human diet is highly desirable. This paper combines the up-to-date information and give a clear image regarding prenylated flavonoids as neutraceuticals.

Humulus lupulus L. as a Natural Source of Functional Biomolecules

Hops (Humulus lupulus L.) are used traditionally in the brewing industry to confer bitterness, aroma, and flavor to beer. However, in recent years, it has been reported that female inflorescences contain a huge variety of bioactive compounds. Due to the growing interest of the consumers by natural ingredients, intense research has been carried out in the last years to find new sources of functional molecules. This review collects the works about the bioactive potential of hops with applications in the food, pharmaceutical, or cosmetic industries. Moreover, an overview of the main extraction technologies to recover biomolecules from hops is shown. Bioactivities of hop extracts such as antibacterial, antifungal, cardioprotective, antioxidant, anti-inflammatory, anticarcinogenic, and antiviral are also summarized. It can be concluded that hops present a high potential of bioactive ingredients with high quality that can be used as preservative agents in fresh foods, extending their shelf life, and they can be incorporated in cosmetic formulation for skincare as well.

Expression of long non-coding RNA SFTA1P and its function in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is a major type of lung cancer with high morbidity and mortality. Long non-coding RNAs (lncRNAs) have been reported to be important in development and progression of NSCLC. However, the role of lncRNA SFTA1P remains unclear. This study aims to explore the clinical roles, biological function, and mechanism of SFTA1P in NSCLC. SFTA1P expression was estimated by the quantitative real-time polymerase chain reaction (qRT-PCR) of 90 pairs of tissue samples, the Cancer Genome Atlas (TCGA) database and microarray. After overexpressing SFTA1P, NSCLC cell proliferation, cycle, and apoptosis were detected. We found that the expression of SFTA1P was significantly downregulated in NSCLC tissues with high diagnostic value (AUC = 0.87), which was consistent with the results of TCGA and microarray data. For the analysis of clinical features, the results revealed that SFTA1P expression was closely related to the pathological type (P < 0.01). Furthermore, the cell function results suggested that the overexpression of SFTA1P triggered cell cycle arrest in the S-phase (P < 0.05). From a mechanistic perspective, the results showed that the PI3K-AKT signaling pathway was inhibited after overexpression of SFTA1P in NSCLC. Taken together, this work supported that SFTA1P may play a suppressing role in the tumorigenesis of NSCLC by modulating PI3K-AKT signaling pathway to influence cell cycle, which provides a potential and prospective biomarker for NSCLC.

Glycopolymer decorated multiwalled carbon nanotubes for dual targeted breast cancer therapy

Carbon-based nanomaterials (CNMs) have attracted great attention in biomedical applications such as cancer imaging and therapy. CNMs, which are currently used in a wide range of applications, suffer from drawbacks of toxicity and low biocompatibility. Either noncovalent or covalent functionalization of CNMs with hydrophilic and biocompatible polymers which help to block hydrophobic interactivity between CNMs and cells can greatly increase their biocompatibility by eliminating their probable toxicity towards living organisms. In this report, we present a comparison of both noncovalent and covalent functionalization approaches in order to introduce a biocompatible glycoblock copolymer onto multi-walled carbon nanotubes (CNTs) in order to enhance their potential in therapies. An anticancer drug (doxorubicin, Dox) was conjugated with two different end functionalized poly(1-O-methacryloyl-β-d-fructopyranose-b-(2-methacryloxyethoxy))benzaldehyde glycoblock copolymers, which were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization, by either noncovalent or covalent tethering. CNTs were coated separately with the synthesized drug-conjugated glycoblock copolymers and folic acid (FA) to obtain an efficient drug delivery platform for dual-targeting of glucose transporter protein (GLUT5) and folic acid receptors (FR) in breast cancer. A library of synthesized monomers, polymers and prepared glycoblock copolymer coated CNTs (hybrid-CNTs) using both approaches were comprehensively characterized by various techniques. Transmission electron microscopy measurements showed the homogeneous, smooth morphology of the prepared Dox-conjugated glycoblock copolymer coating of CNTs and confocal laser scanning microscopy images displayed successful cellular internalization of hybrid-CNTs in the MCF-7 and MDA-MB-231 human breast cancer cell lines. This research demonstrates the potential of hybrid-CNTs as a biocompatible drug delivery system as well as in vitro use of Dox-conjugated vehicles for dual receptor mediated breast cancer therapy.

The Role of Polyphenol (Flavonoids) Compounds in the Treatment of Cancer Cells

Cancer remains a second leading cause of deaths and major public health problem. It occurs due to extensive DNA damage caused by ultraviolet radiations, ionizing radiations, environmental agents, therapeutic agents, etc. Among all cancers, the most frequently diagnosed cancers are lung (12.7%), breast (10.9%), colorectal (9.7%), and gastric cancer (7.81%). Natural compounds are most favorable against cancer on the count of their anti-cancerous ability, easy to avail and efficient. Among natural compounds, polyphenols (flavonoids, catechin, hesperetin, flavones, quercetin, phenolic acids, ellagic acid, lignans, stilbenes, etc.) represent a large and diverse group used in the prevention and treatment of cancer. Natural flavonoids are derived from different plant sources and from various medicinal plants including Petroselinum crispum, Apium graveolens, Flemingia vestita, Phyllanthus emblica, etc. Natural flavonoids possess antioxidant, anti-inflammation, as well as anti-cancerous activities through multiple pathways, they induce apoptosis in breast, colorectal, and prostate cancers, lower the nucleoside diphosphate kinase-B activity in lung, bladder and colon cancers, inhibit cell-proliferation and cell cycle arrest by suppressing the NF-kB pathway in various cancers, etc. The current review summarized the anticancer activities of natural polyphenols and their mechanisms of action.

Combinatorial Epigenetics Impact of Polyphenols and Phytochemicals in Cancer Prevention and Therapy

Polyphenols are potent micronutrients that can be found in large quantities in various food sources and spices. These compounds, also known as phenolics due to their phenolic structure, play a vital nutrient-based role in the prevention of various diseases such as diabetes, cardiovascular diseases, neurodegenerative diseases, liver disease, and cancers. However, the function of polyphenols in disease prevention and therapy depends on their dietary consumption and biological properties. According to American Cancer Society statistics, there will be an expected rise of 23.6 million new cancer cases by 2030. Due to the severity of the increased risk, it is important to evaluate various preventive measures associated with cancer. Relatively recently, numerous studies have indicated that various dietary polyphenols and phytochemicals possess properties of modifying epigenetic mechanisms that modulate gene expression resulting in regulation of cancer. These polyphenols and phytochemicals, when administrated in a dose-dependent and combinatorial-based manner, can have an enhanced effect on epigenetic changes, which play a crucial role in cancer prevention and therapy. Hence, this review will focus on the mechanisms of combined polyphenols and phytochemicals that can impact various epigenetic modifications such as DNA methylation and histone modifications as well as regulation of non-coding miRNAs expression for treatment and prevention of various types of cancer.

Flavonoids and the Risk of Gastric Cancer: An Exploratory Case-Control Study in the MCC-Spain Study

Several epidemiological studies have investigated the association between the dietary flavonoid intake and gastric cancer (GC) risk; however, the results remain inconclusive. Investigating the relationship between the different classes of flavonoids and the histological types and origin of GC can be of interest to the research community. We used data from a population-based multi-case control study (MCC-Spain) obtained from 12 different regions of Spain. 2700 controls and 329 GC cases were included in this study. Odds ratios (ORs) were calculated using the mixed effects logistic regression considering quartiles of flavonoid intakes and log2. Flavonoid intake was associated with a lower GC risk (ORlog2 = 0.76; 95% CI = 0.65-0.89; ORq4vsq1 = 0.60; 95%CI = 0.40-0.89; ptrend = 0.007). Inverse and statistically significant associations were observed with anthocyanidins, chalcones, dihydroflavonols and flavan-3-ols. The isoflavanoid intake was positively associated with higher cancer risk, but without reaching a statistical significance. In general, no differences were observed in the GC risk according to the location and histological type. The flavonoid intake seems to be a protective factor against GC within the MCC-study. This effect may vary depending on the flavonoid class but not by the histological type and location of the tumor. Broader studies with larger sample size and greater geographical variability are necessary.

Phenolic Compounds from Humulus lupulus as Natural Antimicrobial Products: New Weapons in the Fight against Methicillin Resistant Staphylococcus aureus, Leishmania mexicana and Trypanosoma brucei Strains

New anti-infective agents are urgently needed to fight microbial resistance. Methicillin-resistant Staphylococcus aureus (MRSA) strains are particularly responsible for complicated pathologies that are difficult to treat due to their virulence and the formation of persistent biofilms forming a complex protecting shell. Parasitic infections caused by Trypanosoma brucei and Leishmania mexicana are also of global concern, because of the mortality due to the low number of safe and effective treatments. Female inflorescences of hop produce specialized metabolites known for their antimicrobial effects but underexploited to fight against drug-resistant microorganisms. In this study, we assessed the antimicrobial potential of phenolic compounds against MRSA clinical isolates, T. brucei and L. mexicana. By fractionation process, we purified the major prenylated chalcones and acylphloroglucinols, which were quantified by UHPLC-UV in different plant parts, showing their higher content in the active flowers extract. Their potent antibacterial action (MIC < 1 µg/mL for the most active compound) was demonstrated against MRSA strains, through kill curves, post-antibiotic effects, anti-biofilm assays and synergy studies with antibiotics. An antiparasitic activity was also shown for some purified compounds, particularly on T. brucei (IC₅₀ < 1 to 11 µg/mL). Their cytotoxic activity was assessed both on cancer and non-cancer human cell lines.

Highly Cancer Selective Antiproliferative Activity of Natural Prenylated Flavonoids

Xanthohumol (XN) and four minor hops prenylflavonoids: α,β-dihydroxanthohumol (2HXN), isoxanthohumol (IXN), 8-prenylnaringenin (8PN), and 6-prenylnaringenin (6PN), were tested for antiproliferative activity towards human cancer and normal cell lines. Nonprenylated naringenin (NG) was used as a model compound. Xanthohumol, α,β-dihydroxanthohumol and 6-prenylnaringenin were the most active compounds. Xanthohumol exhibited higher antiproliferative activity than cisplatin (CP) against five cancer cell lines: ovarian resistant to cisplatin A2780cis, breast MDA-MB-231 and T-47D, prostate PC-3, and colon HT-29. Isoxanthohumol was more potent than cisplatin against breast cancer cell lines MDA-MB-231 and T-47D whereas 6-prenylnaringenin was stronger than cisplatin against breast cancer cell line T-47D. It was found that tested chalcones possessed highly selective antiproliferative activity towards all tested breast cancer lines compared to the normal breast MCF 10A cell line (the calculated selectivity index ranged from 5 to 10). Low antiproliferative activity of naringenin indicates the importance of the prenyl group with respect to antiproliferative activity.

Xanthohumol, a prenylated flavonoid from Hops, exerts anticancer effects against gastric cancer in vitro

Xanthohumol (Xn), a prenylated flavonoid isolated from Hops (Humulus lupulus L.), has demonstrated potent anticancer activity in multiple types of cancer. However, the effect of Xn on gastric cancer (GC) remains unknown. The aim of the present study was to investigate the effect of Xn on GC cell proliferation, apoptosis and metastasis. It was observed that Xn decreased the viability of GC cells, with very low or no toxicity to normal gastric epithelial cells GES‑1 at a concentration of 1‑100 µM. The proliferation of AGS cells was inhibited by Xn, as indicated by the decreased number of EdU‑positive cells. Xn treatment increased the number of apoptotic cells, downregulated the expression of Bcl‑2 and upregulated the expression of Bax, suggesting induction of apoptosis. The results from the wound healing and Transwell assays indicated that Xn suppressed AGS cell metastasis. Moreover, Xn induced reactive oxygen species (ROS) overproduction and inhibited nuclear factor (NF)‑κB signaling in AGS cells, which was reversed by the ROS inhibitor N‑acetylcysteine (NAC). NAC suppressed the effect of Xn on the proliferation, apoptosis and metastasis of AGS cells. Taken together, these results suggest that Xn exerts anticancer effects against GC via induction of ROS production and subsequent inhibition of NF‑κB signaling. Therefore, Xn may be a promising candidate treatment against GC progression.

Anticancer Activity and Mechanism of Xanthohumol: A Prenylated Flavonoid From Hops (Humulus lupulus L.)

It has been observed that many phytochemicals, frequently present in foods or beverages, show potent chemopreventive or therapeutic properties that selectively affect cancer cells. Numerous studies have demonstrated the anticancer activity of xanthohumol (Xn), a prenylated flavonoid isolated from hops (Humulus lupulus L.), with a concentration up to 0.96 mg/L in beer. This review aims to summarize the existing studies focusing on the anticancer activity of Xn and its effects on key signaling molecules. Furthermore, the limitations of current studies and challenges for the clinical use of Xn are discussed.

Design, synthesis, and structure-activity relationships of 2-benzylidene-1-indanone derivatives as anti-inflammatory agents for treatment of acute lung injury

Purpose

The purpose of this study was to design and synthesize novel 2-benzylidene-1-indanone derivatives for treatment of acute lung injury.

Methods

A series of 39 novel 2-benzylidene-indanone structural derivatives were synthesized and evaluated for anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated murine primary macrophages.

Results

Most of the obtained compounds effectively inhibited the LPS-induced expression of IL-6 and TNF-α. The most active compound, 8f, was found to significantly reduce LPS-induced pulmonary inflammation, as reflected by reductions in the concentration of total protein, inflammatory cell count, as well as the lung wet/dry ratio in bronchoalveolar lavage (BAL) fluid. Furthermore, 8f effectively inhibited mRNA expression of several inflammatory cytokines after LPS challenge in vitro and in vivo. Administration of 8f also blocked LPS-induced activation of the proinflammatory NF-κB/MAPK signaling pathway.

Conclusion

The simple synthetic preparation and biological properties of these derivatives make these 2-benzylidene-indanone scaffolds promising new entities for the development of anti-inflammatory therapeutics for the treatment of acute lung injury.

Xanthohumol induces paraptosis of leukemia cells through p38 mitogen activated protein kinase signaling pathway

Xanthohumol as a natural polyphenol demonstrates an anticancer activity, but its underlying mechanism remains unclear. In this study, we showed that xanthohumol (XN) induces paraptosis of leukemia cells. The paraptosis is one cell death which is characterized by dilation of the endoplasmic reticulum and/or mitochondria. The results demonstrated that XN treatment significantly inhibited cell proliferation and triggered extensive cytoplasmic vacuolation of HL-60 leukemia cells, but it did not cause the cleavage of caspase-3 protein or apoptosis. In contrast, XN treatment resulted in LC3-II accumulation through blocking of autophagosome maturation. Interestingly, the induction of cytoplasmic vacuolization by XN is not associated with autophagy modulated by XN, therefore, XN-induced cell death of HL-60 leukemia cells is not the classical apoptotic cell death. Intriguingly, XN treatment triggered the dilatation of endoplasma reticulum (ER) and induced ER stress by upregulating C/EBP homologous protein and unfolded protein response regulator Grp78/Bip. Furthermore, XN treatment triggered p38 mitogen activated protein kinase and its specific inhibitor inhibited the paraptosis of HL-60 leukemia cells by XN. In conclusion, we for the first time demonstrated that XN treatment can induce paraptosis of leukemia cells through activation of p38 MAPK signaling.

Advanced glycation end products decrease collagen I levels in fibroblasts from the vaginal wall of patients with POP via the RAGE, MAPK and NF-κB pathways

The present study was carried out to observe the impact of advanced glycation end products (AGEs) on collagen I derived from vaginal fibroblasts in the context of pelvic organ prolapse (POP), and explore the downstream effects on MAPK and nuclear factor-κB (NF-κB) signaling. After treating primary cultured human vaginal fibroblasts (HVFs) derived from POP and non-POP cases with AGEs, cell counting was carried out by sulforhodamine B. The expression levels of collagen I, receptor of advanced glycation end products (RAGE), matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were detected by western blot analysis and PCR. RAGE, MAPK and NF-κB were molecularly and pharmacologically-inhibited by siRNA, SB203580 and PDTC, respectively, and downstream changes were detected by western blot analysis and PCR. Inhibition of HVF proliferation by AGEs occurred more readily in POP patients than that noted in the controls. After treatment with AGEs, collagen I levels decreased and MMP-1 levels increased to a greater extent in the HVFs of POP than that noted in the controls. During this same period, RAGE and TIMP-1 levels remained stable. Following treatment with AGEs and RAGE pathway inhibitors by siRNA, SB203580 and PDTC, the impact induced by AGEs was diminished. The inhibition of p-p38 MAPK alone was not able to block the promoting effect of AGEs on the levels of NF-κB, which suggests that AGEs may function through other pathways, as well as p-p38 MAPK. On the whole, this study demonstrated that AGEs inhibited HVF proliferation in POP cases and decreased the expression of collagen I through RAGE and/or p-p38 MAPK and NF-κB-p-p65 pathways. Our results provide important insights into the collagen I metabolism in HVFs in POP.

In vitro Antioxidant and Antiproliferative Activities of Various Solvent Fractions from Clerodendrum viscosum Leaves

Background:

Free radicals such as reactive oxygen and nitrogen species, generated in the body, play an important role in the fulfillment of various physiological functions but their imbalance in the body lead to cellular injury and various clinical disorders such as cancer, neurodegenaration, and inflammation.

Objective:

The objective of this study is to fight this problem, natural antioxidant from plants can be considered as possible protective agents against various diseases such as cancer which might also modify the redox microenvironment to reduce the genetic instability. This study was designed to evaluate the antioxidant and antiproliferative potential of Clerodendrum viscosum fractions against various carcinomas.

Materials and Methods:

In this present study, 70% methanolic extract of C. viscosum leaves have been fractionated to obtain hexane, chloroform, ethyl acetate, butanol, and water fractions, which were tested for their antioxidant and anticancer properties.

Results:

It was observed that chloroform and ethyl acetate fractions showed good free radical scavenging properties as well as inhibited the proliferation of human lung cancer (A459), breast (MCF-7), and brain (U87) cells. Moreover, they arrested the cell cycle at G2/M phase of breast and brain cancer. These inhibitory effects were further confirmed by bromodeoxyuridine uptake imaging. Phytochemical investigations further indicate the presence of tannic acid, quercetin, ellagic caid, gallic acid, reserpine, and methyl gallate which might be the reason for these fractions’ antioxidant and antiproliferative activities.

Conclusion:

Clerodendrum viscosum leaf chloroform and Clerodendrum viscosum leaf ethyl acetate fractions from C. viscosum showed good reactive oxygen species and reactive nitrogen species scavenging potential. Both the fractions arrested cell cycle at G2/M phase in MCF-7 and U87 cells which lead to induce apoptosis.

SUMMARY

Crude extract of Clerodendrum viscosum leaves was fractionated using different solvents

Among them, chloroform and ethyl acetate fractions exhibited excellent free radical scavenging properties

The same fractions inhibited the proliferation of human lung cancer (A459), breast (MCF-7), and brain (U87) cells

Chloroform and ethyl acetate fractions arrested the cell cycle at G2/M phase of breast and brain cancer

Phytochemical investigations further indicate the presence of several bioactive principles present in them.

Abbreviations used: CVLME: Clerodendrum viscosum leaf methanolic extract; CVLH: Clerodendrum viscosum leaf hexane; CVLC: Clerodendrum viscosum leaf chloroform; CVLE: Clerodendrum viscosum leaf ethyl acetate; CVLB: Clerodendrum viscosum leaf butanol; CVLW: Clerodendrum viscosum leaf water; BrdU: Bromodeoxyuridine; WST-1: Water soluble tetrazolium salt.

Induction of Apoptosis and Cell Cycle Arrest by Flavokawain C on HT-29 Human Colon Adenocarcinoma via Enhancement of Reactive Oxygen Species Generation, Upregulation of p21, p27, and GADD153, and Inactivation of Inhibitor of Apoptosis Proteins

Chalcones have been shown to exhibit anti-cancer properties by targeting multiple molecular pathways. It was, therefore, of interest to investigate flavokawain C (FKC), a naturally occurring chalcone, which can be isolated from Kava (Piper methysticum Forst) root extract. The aim of this study was to investigate the inhibitory effect of FKC on the growth of HT-29 cells and its underlying mechanism of action. Cell viability of HT-29 cells was assessed by Sulforhodamine B assay after FKC treatment. Induction of apoptosis was examined by established morphological and biochemical assays. ROS generation was determined by dichlorofluorescein fluorescence staining, and superoxide dismutase activity was measured using the spectrophotometric method. Western blotting was used to examine the changes in the protein levels. FKC markedly decreased the cell viability of HT-29 cells and the cells showed dramatic changes in cellular and nuclear morphologies with typical apoptotic features. The induction of apoptosis correlated well with the externalization of phosphatidylserine, DNA fragmentation, decreased mitochondrial membrane potential, activation of caspases, and PARP cleavage. This was associated with an increase in reactive oxygen species and a decrease in SOD activity. The protein levels of XIAP, c-IAP1, and c-IAP2 were downregulated, whereas the GADD153 was upregulated after FKC treatment. FKC induced cell cycle arrest at the G₁ and G₂/M phases via upregulation of p21 and p27 in a p53-independent manner. Our results provide evidence that FKC has the potential to be developed into chemotherapeutic drug for the treatment of colon adenocarcinoma.

SUMMARY

Flavokawain C inhibited the growth of HT-29 human colon adenocarcinoma cellsFlavokawain C induced apoptosis in HT-29 cells, associated with an increase in reactive oxygen species and a decrease in SOD activityFlavokawain C induced cell cycle arrest at the G₁ and G₂/M phases via upregulation of p21 and p27 in HT-29 cellsHT-29 cells treated with flavokawain C caused downregulation of XIAP, c-IAP1, and c-IAP2, and upregulation of GADD153. Abbreviations used: FKC: Flavokawain C; SRB: Sulforhodamine B; ROS: Reactive oxygen species; SOD: Superoxide dismutase; PARP: Poly(ADP-ribose) polymerase; ER: Endoplasmic reticulum; IAPs: Inhibitor of apoptosis proteins; TUNEL: Transferase dUTP nick end labeling; Annexin V-FITC: Annexin V conjugated with fluorescein isothicyanate.

The natural terthiophene α-terthienylmethanol induces S phase cell cycle arrest of human ovarian cancer cells via the generation of ROS stress

Ovarian cancer is the most lethal gynecological malignancy worldwide. Thiophenes such as terthiophene have been shown to have anti-tumor effects on several cancer cell lines, including ovarian cancer cells. However, the underlying mechanisms behind the anti-proliferative effect of thiophenes are poorly understood. In this study, we investigated the molecular mechanisms underlying the anti-proliferative effect of α-terthienylmethanol, a terthiophene isolated from Eclipta prostrata (False Daisy), on human ovarian cancer cells. We found that α-terthienylmethanol is a more potent inhibitor of cell growth than is cisplatin in human ovarian cancer cells. α-Terthienylmethanol induces cell cycle arrest in ovarian cancer cells, as shown by the accumulation of cells in S phase. In addition, α-terthienylmethanol induced a change in S phase-related proteins cyclin A, cyclin-dependent kinase 2, and cyclin D2. Knockdown of cyclin A using specific siRNAs significantly compromised α-terthienylmethanol-induced S phase arrest. We further demonstrated that α-terthienylmethanol induced an increase in intracellular ROS, and the antioxidant N-acetyl-l-cysteine significantly reversed the S phase arrest induced by α-terthienylmethanol. Moreover, α-terthienylmethanol significantly increased the levels of p-H2AX, a DNA damage marker. These results suggest that α-terthienylmethanol inhibits the growth of human ovarian cancer cells by S phase cell cycle arrest via induction of ROS stress and DNA damage.

Natural Polyphenols for Prevention and Treatment of Cancer

There is much epidemiological evidence that a diet rich in fruits and vegetables could lower the risk of certain cancers. The effect has been attributed, in part, to natural polyphenols. Besides, numerous studies have demonstrated that natural polyphenols could be used for the prevention and treatment of cancer. Potential mechanisms included antioxidant, anti-inflammation as well as the modulation of multiple molecular events involved in carcinogenesis. The current review summarized the anticancer efficacy of major polyphenol classes (flavonoids, phenolic acids, lignans and stilbenes) and discussed the potential mechanisms of action, which were based on epidemiological, in vitro, in vivo and clinical studies within the past five years.

Xanthohumol inhibits the extracellular signal regulated kinase (ERK) signalling pathway and suppresses cell growth of lung adenocarcinoma cells

Aberrant activation of the Ras/MEK/ERK signaling pathway has been frequently observed in non-small-cell lung carcinoma (NSCLC) and its important role in cancer progression and malignant transformation has been documented. Hence, the ERK1/2 kinase cascade becomes a potential molecular target in cancer treatment. Xanthohumol (XN, a prenylated chalcone derived from hope cones) is known to possess a broad spectrum of chemopreventive and anticancer activities. In our studies, the MTT and BrdU assays revealed that XN demonstrated greater antiproliferative activity against A549 lung adenocarcinoma cells than against the lung adenocarcinoma H1563 cell line. We observed that XN was able to suppress the activities of ERK1/2 and p90RSK kinases, followed by inhibition of phosphorylation and activation of the CREB protein. Additionally, the XN treatment of the cancer cells caused upregulation of key cell cycle regulators p53 and p21 as well as downregulation of cyclin D1. As a result, the cytotoxic effect of XN was attributed to the cell cycle arrest at G1 phase and induction of apoptosis indicated by increased caspase-3 activity. Thus, XN might be a promising anticancer drug candidate against lung carcinomas.