The In Vitro and In Vivo Anticancer Properties of Chalcone Flavokawain B through Induction of ROS-Mediated Apoptotic and Autophagic Cell Death in Human Melanoma Cells

Clinical Characteristics and Outcomes of Patients with Well-Differentiated Papillary Peritoneal Mesothelial Tumors

PURPOSE

Well-differentiated papillary peritoneal mesothelial tumors (WDPMTs) are understudied and discrete from peritoneal mesotheliomas (PMs). We report clinicopathologic characteristics and outcomes of a large prospective WDPMT cohort.

METHODS

Patients with WDPMT identified between August 2007 and December 2020 were followed through January 2023. Clinical characteristics and outcomes were annotated. Overall survival (OS) was assessed from pathologic diagnosis. Germline variants were analyzed, and targeted next-generation sequencing (NGS; MSK-IMPACT) data were compared to PMs and diffuse pleural mesotheliomas (DPMs).

RESULTS

Among 54 patients, median age at diagnosis was 55 (range 20-76), 50% were female (n = 27), and 46% were smokers (n = 25; median 8 pack/years). Most (94%, n = 51) WDPMTs were found during surgical explorations for other indications, primarily other malignancies. Two patients underwent surgical resection for WDPMT; none received systemic therapy for WDPMT. Median OS was not reached (19/54; median follow up 4.5 years). Somatic NGS was available for 35% (19/54) of patients. TRAF7 alterations were enriched in WDPMT (89%; 17/19) compared with PM (0%; 0/50; p < 0.0001) and DPM (0%; 0/74; p < 0.0001). In WDPMT compared with PM and DPM, there were less BAP1 (0% [0/0] vs. 4% [8/50] vs. 46% [34/74]; p = 0.001 and p < 0.0001, respectively) and NF2 (0% [0/0] vs. 24% [12/50] vs. 31% [23/74]; p = 0.03 and p = 0.001 respectively) alterations. Pathogenic germline variants were present in 23% (4/17) of WDPMTs.

CONCLUSIONS

Well-differentiated papillary peritoneal mesothelial tumors were primarily incidental findings. There was no WDPMT-related mortality, so there was no distinct role for routine cytoreductive surgery or systemic therapy. Genomic profiles can help to differentiate WDPMT from DPM and PM.

The Induction of G2/M Phase Cell Cycle Arrest and Apoptosis by the Chalcone Derivative 1C in Sensitive and Resistant Ovarian Cancer Cells Is Associated with ROS Generation

Ovarian cancer ranks among the most severe forms of cancer affecting the female reproductive organs, posing a significant clinical challenge primarily due to the development of resistance to conventional therapies. This study investigated the effects of the chalcone derivative 1C on sensitive (A2780) and cisplatin-resistant (A2780cis) ovarian cancer cell lines. Our findings revealed that 1C suppressed cell viability, induced cell cycle arrest at the G2/M phase, and triggered apoptosis in both cell lines. These effects are closely associated with generating reactive oxygen species (ROS). Mechanistically, 1C induced DNA damage, modulated the activity of p21, PCNA, and phosphorylation of Rb and Bad proteins, as well as cleaved PARP. Moreover, it modulated Akt, Erk1/2, and NF-κB signaling pathways. Interestingly, we observed differential effects of 1C on Nrf2 levels between sensitive and resistant cells. While 1C increased Nrf2 levels in sensitive cells after 12 h and decreased them after 48 h, the opposite effect was observed in resistant cells. Notably, most of these effects were suppressed by the potent antioxidant N-acetylcysteine (NAC), underscoring the crucial role of ROS in 1C-induced antiproliferative activity. Moreover, we suggest that modulation of Nrf2 levels can, at least partially, contribute to the antiproliferative effect of chalcone 1C.

Phytochemical-mediated modulation of autophagy and endoplasmic reticulum stress as a cancer therapeutic approach

Autophagy and endoplasmic reticulum (ER) stress are conserved processes that generally promote survival, but can induce cell death when physiological thresholds are crossed. The pro-survival aspects of these processes are exploited by cancer cells for tumor development and progression. Therefore, anticancer drugs targeting autophagy or ER stress to induce cell death and/or block the pro-survival aspects are being investigated extensively. Consistently, several phytochemicals have been reported to exert their anticancer effects by modulating autophagy and/or ER stress. Various phytochemicals (e.g., celastrol, curcumin, emodin, resveratrol, among others) activate the unfolded protein response to induce ER stress-mediated apoptosis through different pathways. Similarly, various phytochemicals induce autophagy through different mechanisms (namely mechanistic target of Rapamycin [mTOR] inhibition). However, phytochemical-induced autophagy can function either as a cytoprotective mechanism or as programmed cell death type II. Interestingly, at times, the same phytochemical (e.g., 6-gingerol, emodin, shikonin, among others) can induce cytoprotective autophagy or programmed cell death type II depending on cellular contexts, such as cancer type. Although there is well-documented mechanistic interplay between autophagy and ER stress, only a one-way modulation was noted with some phytochemicals (carnosol, capsaicin, cryptotanshinone, guangsangon E, kaempferol, and δ-tocotrienol): ER stress-dependent autophagy. Plant extracts are sources of potent phytochemicals and while numerous phytochemicals have been investigated in preclinical and clinical studies, the search for novel phytochemicals with anticancer effects is ongoing from plant extracts used in traditional medicine (e.g., Origanum majorana). Nonetheless, the clinical translation of phytochemicals, a promising avenue for cancer therapeutics, is hindered by several limitations that need to be addressed in future studies.

Shikonin suppresses rheumatoid arthritis by inducing apoptosis and autophagy via modulation of the AMPK/mTOR/ULK-1 signaling pathway

BACKGROUND

The overproliferation of fibroblast-like synoviocytes (FLS) contributes to synovial hyperplasia, a pivotal pathological feature of rheumatoid arthritis (RA). Shikonin (SKN), the active compound from Lithospermum erythrorhizon, exerts anti-RA effects by diverse means. However, further research is needed to confirm SKN's in vitro and in vivo anti-proliferative functions and reveal the underlying specific molecular mechanisms.

PURPOSE

This study revealed SKN's anti-proliferative effects by inducing both apoptosis and autophagic cell death in RA FLS and adjuvant-induced arthritis (AIA) rat synovium, with involvement of regulating the AMPK/mTOR/ULK-1 pathway.

METHODS

SKN's influences on RA FLS were assessed for proliferation, apoptosis, and autophagy with immunofluorescence staining (Ki67, LC3B, P62), EdU incorporation assay, staining assays of Hoechst, Annexin V-FITC/PI, and JC-1, transmission electron microscopy, mCherry-GFP-LC3B puncta assay, and western blot. In AIA rats, SKN's anti-arthritic effects were assessed, and its impacts on synovial proliferation, apoptosis, and autophagy were studied using Ki67 immunohistochemistry, TUNEL, and western blot. The involvement of AMPK/mTOR/ULK-1 pathway was examined via western blot.

RESULTS

SKN suppressed RA FLS proliferation with reduced cell viability and decreased Ki67-positive and EdU-positive cells. SKN promoted RA FLS apoptosis, as evidenced by apoptotic nuclear fragmentation, increased Annexin V-FITC/PI-stained cells, reduced mitochondrial potential, elevated Bax/Bcl-2 ratio, and increased cleaved-caspase 3 and cleaved-PARP protein levels. SKN also enhanced RA FLS autophagy, featuring increased LC3B, reduced P62, autophagosome formation, and activated autophagic flux. Autophagy inhibition by 3-MA attenuated SKN's anti-proliferative roles, implying that SKN-induced autophagy contributes to cell death. In vivo, SKN mitigated the severity of rat AIA while also reducing Ki67 expression, inducing apoptosis, and enhancing autophagy within AIA rat synovium. Mechanistically, SKN modulated the AMPK/mTOR/ULK-1 pathway in RA FLS and AIA rat synovium, as shown by elevated P-AMPK and P-ULK-1 expression and decreased P-mTOR expression. This regulation was supported by the reversal of SKN's in vitro and in vivo effects upon co-administration with the AMPK inhibitor compound C.

CONCLUSION

SKN exerted in vitro and in vivo anti-proliferative properties by inducing apoptosis and autophagic cell death via modulating the AMPK/mTOR/ULK-1 pathway. Our study revealed novel molecular mechanisms underlying SKN's anti-RA effects.

Identification of 3-Aryl-1-benzotriazole-1-yl-acrylonitrile as a Microtubule-Targeting Agent (MTA) in Solid Tumors

Recently, a compound derived from recent scientific advances named 34 has emerged as the focus of this research, the aim of which is to explore its potential impact on solid tumor cell lines. Using a combination of bioinformatics and biological assays, this study conducted an in-depth investigation of the effects of 34. The results of this study have substantial implications for cancer research and treatment. 34 has shown remarkable efficacy in inhibiting the growth of several cancer cell lines, including those representing prostate carcinoma (PC3) and cervical carcinoma (HeLa). The high sensitivity of these cells, indicated by low IC50 values, underscores its potential as a promising chemotherapeutic agent. In addition, 34 has revealed the ability to induce cell cycle arrest, particularly in the G2/M phase, a phenomenon with critical implications for tumor initiation and growth. By interfering with DNA replication in cancer cells, 34 has shown the capacity to trigger cell death, offering a new avenue for cancer treatment. In addition, computational analyses have identified key genes affected by 34 treatment, suggesting potential therapeutic targets. These genes are involved in critical biological processes, including cell cycle regulation, DNA replication and microtubule dynamics, all of which are central to cancer development and progression. In conclusion, this study highlights the different mechanisms of 34 that inhibit cancer cell growth and alter the cell cycle. These promising results suggest the potential for more effective and less toxic anticancer therapies. Further in vivo validation and exploration of combination therapies are critical to improve cancer treatment outcomes.

Methoxychalcones as potential anticancer agents for colon cancer: Is membrane perturbing potency relevant?

Chalcones are naturally produced by many plants, and constitute precursors for the synthesis of flavons and flavanons. They were shown to possess antibacterial, antifungal, anti-cancer, and anti- inflammatory properties. The goal of the study was to assess the suitability of three synthetic methoxychalcones as potential anticancer agents. In a panel of colon cancer cell lines they were demonstrated to be cytotoxic, proapoptotic, causing cell cycle arrest, and increasing intracellular level of reactive oxygen species. Anticancer activity of the compounds was not diminished in the presence of stool extract containing microbial enzymes that could change the structure of chalcones. Moreover, methoxychalcones interacted strongly with model phosphatidylcholine membranes as detected by differential scanning calorimetry. Metohoxychalcones particularly affected the properties of lipid domains in giant unilamellar liposomes formed from raft-mimicking lipid composition. This may be of importance since many molecular targets for therapy of metastatic colon cancer are raft-associated receptors (e.g., receptor tyrosine kinases). The importance of membrane perturbing potency of methoxychalcones for their biological activity was additionally corroborated by the results obtained by molecular modelling.

Flavokawain C inhibits proliferation and migration of liver cancer cells through FAK/PI3K/AKT signaling pathway

PURPOSE

This study investigated the potential applicability and the underlying mechanisms of flavokawain C, a natural compound derived from kava extracts, in liver cancer treatment.

METHODS

Drug distribution experiment used to demonstrate the preferential tissues enrichment of flavokawain C. Cell proliferation, apoptosis and migration effect of flavokawain C were determined by MTT, colony formation, EdU staining, cell adhesion, transwell, flow cytometry and western blot assay. The mechanism was explored by comet assay, immunofluorescence assay, RNA-seq-based Kyoto encyclopedia of genes and genomes analysis, molecular dynamics, bioinformatics analysis and western blot assay. The anticancer effect of flavokawain C was further confirmed by xenograft tumor model.

RESULTS

The studies first demonstrated the preferential enrichment of flavokawain C within liver tissues in vivo. The findings demonstrated that flavokawain C significantly inhibited proliferation and migration of liver cancer cells, induced cellular apoptosis, and triggered intense DNA damage along with strong DNA damage response. The findings from RNA-seq-based KEGG analysis, molecular dynamics, bioinformatics analysis, and western blot assay mechanistically indicated that treatment with flavokawain C notably suppressed the FAK/PI3K/AKT signaling pathway in liver cancer cells. This effect was attributed to the induction of gene changes and the binding of flavokawain C to the ATP sites of FAK and PI3K, resulting in the inhibition of their phosphorylation. Additionally, flavokawain C also displayed the strong capacity to inhibit Huh-7-derived xenograft tumor growth in mice with minimal adverse effects.

CONCLUSIONS

These findings identified that flavokawain C is a promising anticancer agent for liver cancer treatment.

Multienzymatic biotransformation of flavokawain B by entomopathogenic filamentous fungi: structural modifications and pharmacological predictions

BACKGROUND

Flavokawain B is one of the naturally occurring chalcones in the kava plant (Piper methysticum). It exhibits anticancer, anti-inflammatory and antimalarial properties. Due to its therapeutic potential, flavokawain B holds promise for the treatment of many diseases. However, due to its poor bioavailability and low aqueous solubility, its application remains limited. The attachment of a sugar unit impacts the stability and solubility of flavonoids and often determines their bioavailability and bioactivity. Biotransformation is an environmentally friendly way to improve the properties of compounds, for example, to increase their hydrophilicity and thus affect their bioavailability. Recent studies proved that entomopathogenic filamentous fungi from the genera Isaria and Beauveria can perform O-methylglycosylation of hydroxyflavonoids or O-demethylation and hydroxylation of selected chalcones and flavones.

RESULTS

In the present study, we examined the ability of entomopathogenic filamentous fungal strains of Beauveria bassiana, Beauveria caledonica, Isaria farinosa, Isaria fumosorosea, and Isaria tenuipes to transform flavokawain B into its glycosylated derivatives. The main process occurring during the reaction is O-demethylation and/or hydroxylation followed by 4-O-methylglycosylation. The substrate used was characterized by low susceptibility to transformations compared to our previously described transformations of flavones and chalcones in the cultures of the tested strains. However, in the culture of the B. bassiana KCh J1.5 and BBT, Metarhizium robertsii MU4, and I. tenuipes MU35, the expected methylglycosides were obtained with high yields. Cheminformatic analyses indicated altered physicochemical and pharmacokinetic properties in the derivatives compared to flavokawain B. Pharmacological predictions suggested potential anticarcinogenic activity, caspase 3 stimulation, and antileishmanial effects.

CONCLUSIONS

In summary, the study provided valuable insights into the enzymatic transformations of flavokawain B by entomopathogenic filamentous fungi, elucidating the structural modifications and predicting potential pharmacological activities of the obtained derivatives. The findings contribute to the understanding of the biocatalytic capabilities of these microbial cultures and the potential therapeutic applications of the modified flavokawain B derivatives.

Proteomic Analysis Reveals the Effects of Different Dietary Protein Levels on Growth and Development of Jersey-Yak

Jersey-yak is a hybrid offspring of Jersey cattle and yak (Bos grunniens). Changing the feeding system of Jersey-yak can significantly improve its growth performance. In this study, tandem mass tag (TMT) proteomics technology was used to determine the differentially expressed proteins (DEPs) of the longissimus lumborum (LL) muscle of Jersey-yak fed different protein levels of diet. The results showed that compared with the traditional grazing feeding, the growth performance of Jersey-yaks was significantly improved by crude protein supplementation after grazing. A total of 3368 proteins were detected in these muscle samples, of which 3365 were quantified. A total of 434 DEPs were identified. Through analyses, it was found that some pathways related to muscle growth and development were significantly enriched, such as Rap1 signaling pathway, mTOR signaling pathway, and TGF-beta signaling pathway. A number of DEPs enriched in these pathways are related to muscle cell development, differentiation, and muscle development, including integrin subunit alpha 7 (ITGA7), myosin heavy chain 8 (MYH8), and collagen type XII alpha 1 chain (COL12A1). In conclusion, the results of this study provide insights into the proteomics of different feeding patterns of Jersey-yak, providing a stronger basis for further understanding the biological mechanism of hybrid varieties.

Evaluation of the Antitumor Activity of Quaternary Ammonium Surfactants

Quaternary ammonium surfactants, due to their diverse chemical structure and their biological properties, can be used in medicine as DNA carriers, disinfectants, and antimicrobial and antitumor agents. In this study, using melanoma A375, colon adenocarcinoma HT-29 and normal human dermal fibroblast (NHDF) cells, we tested the hypothesis that the quaternary ammonium surfactants 2-dodecanoyloxyethyl)trimethylammonium bromide (DMM-11), 2-dodecanoyloxypropyl)trimethylammonium bromide (DMPM-11) and 2-pentadecanoyloxymethyl)trimethylammonium bromide (DMGM-14) act selectively against cancer cells. The results showed that these compounds led to the initiation of the apoptotic process of programmed cell death, as evidenced by the ratio of the relative expression of Bax protein to Bcl-2. The encapsulation of surfactants in liposomes allowed lower concentrations to be used. Moreover, encapsulation reduced their toxicity towards non-cancerous cells. The anticancer efficiency and apoptotic effect of the liposomal formulations with surfactants (DMM-11, DMPM-11 and DMGM-14) were higher than those of surfactant-free liposomes. Therefore, quaternary ammonium surfactant-loaded liposomes show significant potential as delivery vehicles for the treatment of melanoma and colon cancers. The use of nano-formulations offers the advantage of optimizing quaternary ammonium surfactant delivery for improved anticancer therapy.

The kava chalcone flavokawain B exerts inhibitory activity and synergizes with BCL-2 inhibition in malignant B-cell lymphoma

BACKGROUND

B-cell lymphoma, which originates from B cells at diverse differentiation stages, is the most common non-Hodgkin lymphoma with tremendous treatment challenges and unsatisfactory clinical outcomes. Flavokawain B (FKB), a naturally occurring chalcone extracted from kava, possesses promising anticancer properties. However, evidence on the effects of FKB on hematological malignancies, particularly lymphomas, remains scarce.

PURPOSE

This study aimed to investigate the antilymphoma effect of FKB and its underlying mechanisms.

STUDY DESIGN/METHODS

Proliferation assays, flow cytometry, and western blotting were employed to determine whether and how FKB affected B-cell lymphoma cell lines in vitro. Xenograft mouse models were established to evaluate the antilymphoma efficacy of FKB in vivo.

RESULTS

FKB reduced the viability of a panel of B-cell lymphoma cell lines in a dose- and time-dependent manner. Mitochondrial apoptosis was markedly induced by FKB, as evidenced by an increased percentage of annexin V-positive cells, a loss of mitochondrial membrane potential, and cleavage of caspase-3 and PARP. Moreover, FKB inhibited BCL-XL expression and synergized with the BCL-2 inhibitor ABT-199. Mechanistically, FKB treatment decreased the phosphorylation of Akt, mammalian target of rapamycin (mTOR), glycogen synthase kinase-3β (GSK3β), and ribosomal protein S6 (RPS6). Pharmacological blockage of phosphoinositide 3-kinase (PI3K), Akt, or GSK3β potentiated the activity of FKB, indicating the involvement of the PI3K/Akt cascade in FKB-mediated inhibitory effects. In mouse xenograft models, the intraperitoneal administration of FKB significantly decreased lymphoma growth, accompanied by diminished mitosis and Ki-67 staining of tumor tissues.

CONCLUSION

Our data demonstrate the robust therapeutic potential of FKB in the treatment of B-cell lymphoma.

A Novel Tri-Hydroxy-Methylated Chalcone Isolated from Chromolaena tacotana with Anti-Cancer Potential Targeting Pro-Survival Proteins

Chromolaena tacotana (Klatt) R. M. King and H. Rob (Ch. tacotana) contains bioactive flavonoids that may have antioxidant and/or anti-cancer properties. This study investigated the potential anti-cancer properties of a newly identified chalcone isolated from the inflorescences of the plant Chromolaena tacotana (Klatt) R. M. King and H. Rob (Ch. tacotana). The chalcone structure was determined using HPLC/MS (QTOF), UV, and NMR spectroscopy. The compound cytotoxicity and selectivity were evaluated on prostate, cervical, and breast cancer cell lines using the MTT assay. Apoptosis and autophagy induction were assessed through flow cytometry by detecting annexin V/7-AAD, active Casp3/7, and LC3B proteins. These results were supported by Western blot analysis. Mitochondrial effects on membrane potential, as well as levels of pro- and anti-apoptotic proteins were analyzed using flow cytometry, fluorescent microscopy, and Western blot analysis specifically on a triple-negative breast cancer (TNBC) cell line. Furthermore, molecular docking (MD) and molecular dynamics (MD) simulations were performed to evaluate the interaction between the compounds and pro-survival proteins. The compound identified as 2',3,4-trihydroxy-4',6'-dimethoxy chalcone inhibited the cancer cell line proliferation and induced apoptosis and autophagy. MDA-MB-231, a TNBC cell line, exhibited the highest sensitivity to the compound with good selectivity. This activity was associated with the regulation of mitochondrial membrane potential, activation of the pro-apoptotic proteins, and reduction of anti-apoptotic proteins, thereby triggering the intrinsic apoptotic pathway. The chalcone consistently interacted with anti-apoptotic proteins, particularly the Bcl-2 protein, throughout the simulation period. However, there was a noticeable conformational shift observed with the negative autophagy regulator mTOR protein. Future studies should focus on the molecular mechanisms underlying the anti-cancer potential of the new chalcone and other flavonoids from Ch. tacotana, particularly against predominant cancer cell types.

Clinical-mediated discovery of pyroptosis in CD8+ T cell and NK cell reveals melanoma heterogeneity by single-cell and bulk sequence

Histologically, melanoma tissues had fewer positive cells percentage of pyroptosis-related genes (PRGs), GZMA, GSDMB, NLRP1, IL18, and CHMP4A in epidermal than in normal skin. Pyroptosis, a new frontier in cancer, affects the tumor microenvironment and tumor immunotherapy. Nevertheless, the role of pyroptosis remains controversial, which reason is partly due to the heterogeneity of the cellular composition in melanoma. In this study, we present a comprehensive analysis of the single-cell transcriptome landscape of pyroptosis in melanoma specimens. Our findings reveal dysregulation in the expression of PRGs, particularly in immune cells, such as CD8+ cells (representing CD8+ T cells) and CD57+ cells (representing NK cells). Additionally, the immunohistochemical and multiplex immunofluorescence staining experiments results further confirmed GZMA+ cells and GSDMB+ cells were predominantly expressed in immune cells, especially in CD8 + T cells and NK cells. Melanoma specimens secreted a minimal presence of GZMA+ merged CD8+ T cells (0.11%) and GSDMB+ merged CD57+ cells (0.08%), compared to the control groups exhibiting proportions of 4.02% and 0.62%, respectively. The aforementioned findings indicate that a reduced presence of immune cells within tumors may play a role in diminishing the ability of pyroptosis, consequently posing a potential risk to the anti-melanoma properties. To quantify clinical relevance, we constructed a prognostic risk model and an individualized nomogram (C-index=0.58, P = 0.002), suggesting a potential role of PRGs in malignant melanoma prevention. In conclusion, our integrated single-cell and bulk RNA-seq analysis identified immune cell clusters and immune gene modules with experiment validation, contributing to our better understanding of pyroptosis in melanoma.

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.

Antrodia camphorata and coenzyme Q0 , a novel quinone derivative of Antrodia camphorata, impede HIF-1α and epithelial-mesenchymal transition/metastasis in human glioblastoma cells

Antrodia camphorata (AC) and Coenzyme Q₀ (CoQ₀ ), a novel quinone derivative of AC, exhibits antitumor activities. The present study evaluated EMT/metastasis inhibition and autophagy induction aspects of AC and CoQ₀ in human glioblastoma (GBM8401) cells. Our findings revealed that AC treatment (0-150 μg/mL) hindered tumor cell proliferation and migration/invasion in GBM8401 cells. Notably, AC treatment inhibited HIF-1α and EMT by upregulating epithelial marker protein E-cadherin while downregulating mesenchymal proteins Twist, Slug, Snail, and β-catenin. There was an appearance of the autophagy markers LC3-II and p62/SQSTM1, while ATG4B was downregulated by AC treatment. We also found that CoQ₀ (0-10 μM) could inhibit migration and invasion in GBM8401 cells. In particular, E-cadherin was elevated and N-cadherin, Vimentin, Twist, Slug, and Snail, were reduced upon CoQ₀ treatment. In addition, MMP-2/-9 expression and Wnt/β-catenin pathways were downregulated. Furthermore, autophagy inhibitors 3-MA or CQ reversed the CoQ₀ -elicited suppression of migration/invasion and metastasis-related proteins (Vimentin, Snail, and β-catenin). Results suggested autophagy-mediated antiEMT and antimetastasis upon CoQ₀ treatment. CoQ₀ inhibited HIF-1α and metastasis in GBM8401 cells under normoxia and hypoxia. HIF-1α knockdown using siRNA accelerated CoQ₀ -inhibited migration. Finally, CoQ₀ exhibited a prolonged survival rate in GBM8401-xenografted mice. Treatment with Antrodia camphorata/CoQ₀ inhibited HIF-1α and EMT/metastasis in glioblastoma.

In vitro and in vivo anti-tumor activity of Antrodia salmonea against twist-overexpressing HNSCC cells: Induction of ROS-mediated autophagic and apoptotic cell death

Head and neck squamous cell carcinoma (HNSCC) is a relatively common malignancy, characterized by lethal morbidity. Herein, we attempted to investigate the autophagy/apoptosis activities of the submerged fermented broths of Antrodia salmonea (AS) in HNSCC Twist-overexpressing (OECM-1 and FaDu-Twist) cells. AS (0-150 μg/mL) effectively reduced cell viability, colony formation, and downregulated Twist expression in OECM-1 and FaDu-Twist cells compared to FaDu cells. AS- induced apoptosis was mainly associated with activation of caspase-3, PARP cleavage, increased expression of VDAC-1 and disproportionation of Bax/Bcl-2. Annexin V/PI staining suggested late apoptosis induction by AS treatment. AS exhibits enhanced autophagy process mediated via LC3-I/II accumulation, increased acidic vesicular organelles (AVOs) formation and p62/SQSTM1 expression feeding into the apoptotic program. However, pre-treatment with autophagy blockers 3-MA and CQ significantly diminished AS-induced cell death. Additionally, suppression of AS-induced ROS release by treatment with antioxidant N-acetylcysteine (NAC) resulted in reduction of apoptotic and autophagic cell death. In vivo studies strengthened the above observations and showed that AS effectively reduced the tumor volume and tumor weight in OECM-1-xenografted nude mice. This study discovered that Antrodia salmonea exhibits a novel anti-cancer mechanism which could be harnessed as a new potent drug for HNSCC treatment.

Pharmacotherapeutics Applications and Chemistry of Chalcone Derivatives

Chalcones have been well examined in the extant literature and demonstrated antibacterial, antifungal, anti-inflammatory, and anticancer properties. A detailed evaluation of the purported health benefits of chalcone and its derivatives, including molecular mechanisms of pharmacological activities, can be further explored. Therefore, this review aimed to describe the main characteristics of chalcone and its derivatives, including their method synthesis and pharmacotherapeutics applications with molecular mechanisms. The presence of the reactive α,β-unsaturated system in the chalcone's rings showed different potential pharmacological properties, including inhibitory activity on enzymes, anticancer, anti-inflammatory, antibacterial, antifungal, antimalarial, antiprotozoal, and anti-filarial activity. Changing the structure by adding substituent groups to the aromatic ring can increase potency, reduce toxicity, and broaden pharmacological action. This report also summarized the potential health benefits of chalcone derivatives, particularly antimicrobial activity. We found that several chalcone compounds can inhibit diverse targets of antibiotic-resistance development pathways; therefore, they overcome resistance, and bacteria become susceptible to antibacterial compounds. A few chalcone compounds were more active than conventional antibiotics, like vancomycin and tetracycline. On another note, a series of pyran-fused chalcones and trichalcones can block the NF-B signaling complement system implicated in inflammation, and several compounds demonstrated more potent lipoxygenase inhibition than NSAIDs, such as indomethacin. This report integrated discussion from the domains of medicinal chemistry, organic synthesis, and diverse pharmacological applications, particularly for the development of new anti-infective agents that could be a useful reference for pharmaceutical scientists.

Chalcone-Acridine Hybrid Suppresses Melanoma Cell Progression via G2/M Cell Cycle Arrest, DNA Damage, Apoptosis, and Modulation of MAP Kinases Activity

This study was focused on investigating the antiproliferative effects of chalcone hybrids in melanoma cancer cells. Among seven chalcone hybrids, the chalcone-acridine hybrid 1C was the most potent and was selected for further antiproliferative mechanism studies. This in vitro study revealed the potent antiproliferative effect of 1C via cell cycle arrest and apoptosis induction. Cell cycle arrest at the G2/M phase was associated with modulation of expression or phosphorylation of specific cell cycle-associated proteins (cyclin B1, p21, and ChK1), tubulins, as well as with the activation of the DNA damage response pathway. Chalcone 1C also induced apoptosis accompanied by mitochondrial dysfunction evidenced by a decrease in mitochondrial membrane potential, increase in Bax/Bcl-xL ratio and cytochrome c release followed by caspase 3/7 activation. In addition, increased phosphorylation of MAP kinases (Erk1/2, p38 and JNK) was observed in chalcone 1C-treated melanoma cells. The strong antiproliferative activities of this chalcone-acridine hybrid suggest that it may be useful as an antimelanoma agent in humans.

Effects of Para-Toluenesulfonamide on Canine Melanoma Xenotransplants in a BALB/c Nude Mouse Model

The pharmacological pathway of para-toluenesulfonamide (PTS) restricts the kinase activity of the mammalian target of rapamycin, potentially leading to reductions in cell division, cell growth, cell proliferation, and inflammation. These pathways have a critical effect on tumorigenesis. We aimed to examine the antitumor effect of PTS or PTS combined with cisplatin on canine melanoma implanted in BALB/c nude mice by estimating tumor growth, apoptosis expression, inflammation, and metastasis. The mice were randomly divided into four groups: control, cisplatin, PTS, and PTS combined with cisplatin. Mice treated with PTS or PTS combined with cisplatin had retarded tumor growth and increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase phosphorylation, decreased inflammatory cytokine levels, reduced inflammation-related factors, enhanced anti-inflammation-related factors, and inhibition of metastasis-related factors. Mice treated with PTS combined with cisplatin exhibited significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with those treated with cisplatin or PTS alone. PTS or PTS combined with cisplatin could retard canine melanoma growth and inhibit tumorigenesis. PTS and cisplatin were found to have an obvious synergistic tumor-inhibiting effect on canine melanoma. PTS alone and PTS combined with cisplatin may be antitumor agents for canine melanoma treatment.

Flavokawain B alleviates LPS-induced acute lung injury via targeting myeloid differentiation factor 2

Acute lung injury (ALI) is a sudden onset systemic inflammatory response. ALI causes severe morbidity and death and currently no effective pharmacological therapies exist. Natural products represent an excellent resource for discovering new drugs. Screening anti-inflammatory compounds from the natural product bank may offer viable candidates for molecular-based therapies for ALI. In this study, 165 natural compounds were screened for anti-inflammatory activity in lipopolysaccharide (LPS)-challenged macrophages. Among the screened compounds, flavokawain B (FKB) significantly reduced LPS-induced pro-inflammatory IL-6 secretion in macrophages. FKB also reduced the formation of LPS/TLR4/MD2 complex by competitively binding to MD2, suppressing downstream MAPK and NF-κB signaling activation. Finally, FKB treatment of mice reduced LPS-induced lung injury, systemic and local inflammatory cytokine production, and macrophage infiltration in lungs. These protective activities manifested as increased survival in the ALI model, and reduced mortality upon bacterial infection. In summary, we demonstrate that the natural product FKB protects against LPS-induced lung injury and sepsis by interacting with MD2 and inhibiting inflammatory responses. FKB may potentially serve as a therapeutic option for the treatment of ALI.

Brassinin Enhances Apoptosis in Hepatic Carcinoma by Inducing Reactive Oxygen Species Production and Suppressing the JAK2/STAT3 Pathway

Plants from the family Brassicaceae produce brassinin (BSN), which is an essential indole phytoalexin. BSN can kill certain types of cancer cells. Using hepatocarcinoma (HCC) cells, we examined the molecular mechanisms of BSN. We found that HCC cell growth was suppressed and apoptosis was induced by BSN via the downregulation of the JAK/STAT3 pathway. The cytoplasmic latent transcription factor STAT3, belonging to the STAT family, acted as both a signal transducer and an activator and was linked to tumor progression and decreased survival. BSN incubation caused HCC cells to produce reactive oxygen species (ROS). By activating caspase-9/-3 and PARP cleavage, Bcl-2 was reduced, and apoptosis was increased. BSN inhibited constitutive STAT3, JAK2, and Src phosphorylation. The JAK/STAT signaling cascade was confirmed by siRNA silencing STAT3 in HCC cells. BSN also suppressed apoptosis by Z-Val-Ala-Asp-Fluoromethylketone (Z-VAD-FMK), an apoptotic inhibitor. N-acetylcysteine (NAC) inhibited the production of ROS and diminished BSN-induced apoptosis. Our findings suggested that BSN has potential as a treatment for cancer.

Programmed Cell Death Alterations Mediated by Synthetic Indole Chalcone Resulted in Cell Cycle Arrest, DNA Damage, Apoptosis and Signaling Pathway Modulations in Breast Cancer Model

Although new chemotherapy significantly increased the survival of breast cancer (BC) patients, the use of these drugs is often associated with serious toxicity. The discovery of novel anticancer agents for BC therapy is expected. This study was conducted to explore the antiproliferative effect of newly synthesized indole chalcone derivative ZK-CH-11d on human BC cell lines. MTT screening, flow cytometry, Western blot, and fluorescence microscopy were used to evaluate the mode of cell death. ZK-CH-11d significantly suppressed the proliferation of BC cells with minimal effect against non-cancer cells. This effect was associated with cell cycle arrest at the G2/M phase and apoptosis induction. Apoptosis was associated with cytochrome c release, increased activity of caspase 3 and caspase 7, PARP cleavage, reduced mitochondrial membrane potential, and activation of the DNA damage response system. Furthermore, our study demonstrated that ZK-CH-11d increased the AMPK phosphorylation with simultaneous inhibition of the PI3K/Akt/mTOR pathway indicating autophagy initiation. However, chloroquine, an autophagy inhibitor, significantly potentiated the cytotoxic effect of ZK-CH-11d in MDA-MB-231 cells indicating that autophagy is not principally involved in the antiproliferative effect of ZK-CH-11d. Taking together the results from our experiments, we assume that autophagy was activated as a defense mechanism in treated cells trying to escape from chalcone-induced harmful effects.

Oxidative Stress and Autophagy as Key Targets in Melanoma Cell Fate

Melanoma originates from the malignant transformation of melanocytes and is one of the most aggressive forms of cancer. The recent approval of several drugs has increased the chance of survival although a significant subset of patients with metastatic melanoma do not show a long-lasting response to these treatments. The complex cross-talk between oxidative stress and the catabolic process autophagy seems to play a central role in all aspects of melanoma pathophysiology, from initiation to progression and metastasis, including drug resistance. However, determining the fine role of autophagy in cancer death and in response to redox disruption is still a fundamental challenge in order to advance both basic and translational aspects of this field. In order to summarize the interactions among reactive oxygen and nitrogen species, autophagy machinery and proliferation/growth/death/apoptosis/survival, we provide here a narrative review of the preclinical evidence for drugs/treatments that modulate oxidative stress and autophagy in melanoma cells. The significance and the potential for pharmacological targeting (also through multiple and combination approaches) of these two different events, which can contribute independently or simultaneously to the fate of melanoma, may help to define new processes and their interconnections underlying skin cancer biology and unravel new reliable approaches.

Shikonin Induced Program Cell Death through Generation of Reactive Oxygen Species in Renal Cancer Cells

Shikonin mitigated tumor cell proliferation by elevating reactive oxygen species (ROS) levels. Herein, we investigated the effects of shikonin on renal cancer cell (RCC) cell proliferation. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay indicated that shikonin dose-dependently reduced the proliferation of Caki-1 and ACHN cells. Shikonin remarkably triggered necrosis and apoptosis in Caki-1 and ACHN cells in proportion to its concentration. Moreover, necrostatin-1 recovered cell viability in the presence of shikonin. Elevated ROS levels and mitochondrial dysfunction were also found in shikonin treatment groups. Pretreatment with N-acetyl cysteine remarkably mitigated shikonin-induced cell death and ROS generation. Western blot analysis revealed that shikonin reduced pro-PARP, pro-caspase-3, and Bcl-2 expression and increased cleavage PARP expression. Enhanced autophagy was also found in the shikonin-treated group as evidenced by acridine orange staining. Moreover, light chain 3B (LC3B)-II accumulation and enhanced p62 expression indicated that autophagy occurred in the shikonin-treated group. LC3B knockdown considerably recovered cell viability in the presence of shikonin. Shikonin treatment elevated p38 activity in a dose-dependent manner. In conclusion, our results revealed that shikonin triggered programmed cell death via the elevation of ROS level and p38 activity in different types of RCC cells. These findings suggested that shikonin may be a potential anti-RCC agent.

Molecular Mechanisms of Antiproliferative Effects of Natural Chalcones

Simple Summary

Despite the important progress in cancer treatment in the past decades, the mortality rates in some types of cancer have not significantly decreased. Therefore, the search for novel anticancer drugs has become a topic of great interest. Chalcones, precursors of flavonoid synthesis in plants, have been documented as natural compounds with pleiotropic biological effects including antiproliferative/anticancer activity. This article focuses on the knowledge on molecular mechanisms of antiproliferative action of chalcones and draws attention to this group of natural compounds that may be of importance in the treatment of cancer disease.

Abstract

Although great progress has been made in the treatment of cancer, the search for new promising molecules with antitumor activity is still one of the greatest challenges in the fight against cancer due to the increasing number of new cases each year. Chalcones (1,3-diphenyl-2-propen-1-one), the precursors of flavonoid synthesis in higher plants, possess a wide spectrum of biological activities including antimicrobial, anti-inflammatory, antioxidant, and anticancer. A plethora of molecular mechanisms of action have been documented, including induction of apoptosis, autophagy, or other types of cell death, cell cycle changes, and modulation of several signaling pathways associated with cell survival or death. In addition, blockade of several steps of angiogenesis and proteasome inhibition has also been documented. This review summarizes the basic molecular mechanisms related to the antiproliferative effects of chalcones, focusing on research articles from the years January 2015–February 2021.

The Anti-Cancer Effects of a Zotarolimus and 5-Fluorouracil Combination Treatment on A549 Cell-Derived Tumors in BALB/c Nude Mice

Zotarolimus is a semi-synthetic derivative of rapamycin and a novel immunosuppressive agent used to prevent graft rejection. The pharmacological pathway of zotarolimus restricts the kinase activity of the mammalian target of rapamycin (mTOR), which potentially leads to reductions in cell division, cell growth, cell proliferation, and inflammation. These pathways have a critical influence on tumorigenesis. This study aims to examine the anti-tumor effect of zotarolimus or zotarolimus combined with 5-fluorouracil (5-FU) on A549 human lung adenocarcinoma cell line implanted in BALB/c nude mice by estimating tumor growth, apoptosis expression, inflammation, and metastasis. We established A549 xenografts in nude mice, following which we randomly divided the mice into four groups: control, 5-FU (100 mg/kg/week), zotarolimus (2 mg/kg/day), and zotarolimus combined with 5-FU. Compared the results with those for control mice, we found that mice treated with zotarolimus or zotarolimus combined with 5-FU retarded tumor growth; increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase (ERK) phosphorylation; decreased inflammation cytokines levels (e.g., IL-1β, TNF-α, and IL-6); reduced inflammation-related factors such as cyclooxygenase-2 (COX-2) protein and nuclear factor-κB (NF-κB) mRNA; enhanced anti-inflammation-related factors including IL-10 and inhibitor of NF-κB kinase α (IκBα) mRNA; and inhibited metastasis-related factors such as transforming growth factor β (TGF-β), CD44, epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF). Notably, mice treated with zotarolimus combined with 5-FU had significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with the groups of mice treated with 5-FU or zotarolimus alone. The in vivo study confirmed that zotarolimus or zotarolimus combined with 5-FU could retard lung adenocarcinoma growth and inhibit tumorigenesis. Zotarolimus and 5-FU were found to have an obvious synergistic tumor-inhibiting effect on lung adenocarcinoma. Therefore, both zotarolimus alone and zotarolimus combined with 5-FU may be potential anti-tumor agents for treatment of human lung adenocarcinoma.

Dendrobium officinale polysaccharide triggers mitochondrial disorder to induce colon cancer cell death via ROS-AMPK-autophagy pathway

The homeostasis between mitochondrial function and autophagy is crucial to the physiological activity of cancer cells, and its mechanism is conducive to the development of anti-tumor drugs. Here, we aimed to explore the effect and mechanism of Dendrobium officinale polysaccharide (DOP) on colon cancer cell line CT26. Our data showed that DOP significantly inhibited the proliferation of CT26 cells and elevated autophagy level. Moreover, DOP disrupted mitochondrial function through increasing reactive oxygen species (ROS) and reducing mitochondrial membrane potential (MMP), thereby impairing ATP biosynthesis, which activated AMPK/mTOR autophagy signaling. Intriguingly, the further experiments demonstrated that DOP-induced cytotoxicity, excessive autophagy and mitochondrial dysfunction were reversed after CT26 cells pretreated with antioxidant (N-acetyl-l-cysteine). Herein, these findings implied that DOP-induced mitochondrial dysfunction and cytotoxic autophagy repressed the propagation of CT26 cells via ROS-ATP-AMPK signaling, providing a new opinion for the study of antineoplastic drugs.

Correction: Hseu, Y.-C., et al. The In Vitro and In Vivo Anticancer Properties of Chalcone Flavokawain B through Induction of ROS-Mediated Apoptotic and Autophagic Cell Death in Human Melanoma Cells. Cancers 2020, 12, 2936

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