RETRACTED: Physcion induces mitochondria-driven apoptosis in colorectal cancer cells via downregulating EMMPRIN

Marine-Derived Anticancer Agents Targeting Apoptotic Pathways: Exploring the Depths for Novel Cancer Therapies

Extensive research has been conducted on the isolation and study of bioactive compounds derived from marine sources. Several natural products have demonstrated potential as inducers of apoptosis and are currently under investigation in clinical trials. These marine-derived compounds selectively interact with extrinsic and intrinsic apoptotic pathways using a variety of molecular mechanisms, resulting in cell shrinkage, chromatin condensation, cytoplasmic blebs, apoptotic bodies, and phagocytosis by adjacent parenchymal cells, neoplastic cells, or macrophages. Numerous marine-derived compounds are currently undergoing rigorous examination for their potential application in cancer therapy. This review examines a total of 21 marine-derived compounds, along with their synthetic derivatives, sourced from marine organisms such as sponges, corals, tunicates, mollusks, ascidians, algae, cyanobacteria, fungi, and actinobacteria. These compounds are currently undergoing preclinical and clinical trials to evaluate their potential as apoptosis inducers for the treatment of different types of cancer. This review further examined the compound's properties and mode of action, preclinical investigations, clinical trial studies on single or combination therapy, and the prospective development of marine-derived anticancer therapies.

Evidence for Anticancer Effects of Chinese Medicine Monomers on Colorectal Cancer

Colorectal cancer is one of the most commonly occurring cancers worldwide. Although clinical reports have indicated the anticancer effects of Chinese herbal medicine, the multiple underlying molecular and biochemical mechanisms of action remain to be fully characterized. Chinese medicine (CM) monomers, which are the active components of CM, serve as the material basis of the functional mechanisms of CM. The aim of this review is to summarize the current experimental evidence from in vitro, in vivo, and clinical studies for the effects of CM monomers in colorectal cancer prevention and treatment, providing some useful references for future research.

A feedback loop between the androgen receptor and 6-phosphogluoconate dehydrogenase (6PGD) drives prostate cancer growth

Alterations to the androgen receptor (AR) signalling axis and cellular metabolism are hallmarks of prostate cancer. This study provides insight into both hallmarks by uncovering a novel link between AR and the pentose phosphate pathway (PPP). Specifically, we identify 6-phosphogluoconate dehydrogenase (6PGD) as an androgen-regulated gene that is upregulated in prostate cancer. AR increased the expression of 6PGD indirectly via activation of sterol regulatory element binding protein 1 (SREBP1). Accordingly, loss of 6PGD, AR or SREBP1 resulted in suppression of PPP activity as revealed by 1,2-¹³C₂ glucose metabolic flux analysis. Knockdown of 6PGD also impaired growth and elicited death of prostate cancer cells, at least in part due to increased oxidative stress. We investigated the therapeutic potential of targeting 6PGD using two specific inhibitors, physcion and S3, and observed substantial anti-cancer activity in multiple models of prostate cancer, including aggressive, therapy-resistant models of castration-resistant disease as well as prospectively collected patient-derived tumour explants. Targeting of 6PGD was associated with two important tumour-suppressive mechanisms: first, increased activity of the AMP-activated protein kinase (AMPK), which repressed anabolic growth-promoting pathways regulated by acetyl-CoA carboxylase 1 (ACC1) and mammalian target of rapamycin complex 1 (mTORC1); and second, enhanced AR ubiquitylation, associated with a reduction in AR protein levels and activity. Supporting the biological relevance of positive feedback between AR and 6PGD, pharmacological co-targeting of both factors was more effective in suppressing the growth of prostate cancer cells than single-agent therapies. Collectively, this work provides new insight into the dysregulated metabolism of prostate cancer and provides impetus for further investigation of co-targeting AR and the PPP as a novel therapeutic strategy.

Physcion and Physcion 8-O-β-D-glucopyranoside: Natural Anthraquinones with Potential Anticancer Activities

Nature has provided prodigious reservoirs of pharmacologically active compounds for drug development since times. Physcion and physcion 8-O-β-D-glucopyranoside (PG) are bioactive natural anthraquinones which exert anti-inflammatory and anticancer properties with minimum or no adverse effects. Moreover, physcion also exhibits anti-microbial and hepatoprotective properties, while PG is known to have anti-sepsis as well as ameliorative activities against dementia. This review aims to highlight the natural sources and anticancer activities of physcion and PG, along with associated mechanisms of actions. On the basis of the literature, physcion and PG regulate multitudinous cell signaling pathways through the modulation of various regulators of cell cycle, protein kinases, microRNAs, transcriptional factors, and apoptosis linked proteins resulting in the effective killing of cancerous cells in vitro as well as in vivo. Both compounds effectively suppress metastasis, furthermore, physcion acts as an inhibitor of 6PGD and also plays an important role in chemosensitization. This review article suggests that physcion and PG are potent anticancer drug candidates, but further investigations on their mechanism of action and pre-clinical trials are mandatory in order to comprehend the full potential of these natural cancer killers in anticancer remedies.

Anthraquinone: a promising scaffold for the discovery and development of therapeutic agents in cancer therapy

Cancer, characterized by uncontrolled malignant neoplasm, is a leading cause of death in both advanced and emerging countries. Although, ample drugs are accessible in the market to intervene with tumor progression, none are totally effective and safe. Natural anthraquinone (AQ) equivalents such as emodin, aloe-emodin, alchemix and many synthetic analogs extend their antitumor activity on different targets including telomerase, topoisomerases, kinases, matrix metalloproteinases, DNA and different phases of cell lines. Nano drug delivery strategies are advanced tools which deliver drugs into tumor cells with minimum drug leakage to normal cells. This review delineates the way AQ derivatives are binding on these targets by abolishing tumor cells to produce anticancer activity and purview of nanoformulations related to AQ analogs.

Assembly and Annotation of a Draft Genome of the Medicinal Plant Polygonum cuspidatum

Polygonum cuspidatum (Japanese knotweed, also known as Huzhang in Chinese), a plant that produces bioactive components such as stilbenes and quinones, has long been recognized as important in traditional Chinese herbal medicine. To better understand the biological features of this plant and to gain genetic insight into the biosynthesis of its natural products, we assembled a draft genome of P. cuspidatum using Illumina sequencing technology. The draft genome is ca. 2.56 Gb long, with 71.54% of the genome annotated as transposable elements. Integrated gene prediction suggested that the P. cuspidatum genome encodes 55,075 functional genes, including 6,776 gene families that are conserved in the five eudicot species examined and 2,386 that are unique to P. cuspidatum. Among the functional genes identified, 4,753 are predicted to encode transcription factors. We traced the gene duplication history of P. cuspidatum and determined that it has undergone two whole-genome duplication events about 65 and 6.6 million years ago. Roots are considered the primary medicinal tissue, and transcriptome analysis identified 2,173 genes that were expressed at higher levels in roots compared to aboveground tissues. Detailed phylogenetic analysis demonstrated expansion of the gene family encoding stilbene synthase and chalcone synthase enzymes in the phenylpropanoid metabolic pathway, which is associated with the biosynthesis of resveratrol, a pharmacologically important stilbene. Analysis of the draft genome identified 7 abscisic acid and water deficit stress-induced protein-coding genes and 14 cysteine-rich transmembrane module genes predicted to be involved in stress responses. The draft de novo genome assembly produced in this study represents a valuable resource for the molecular characterization of medicinal compounds in P. cuspidatum, the improvement of this important medicinal plant, and the exploration of its abiotic stress resistance.

Physcion Synergistically Enhances the Cytotoxicity of Sorafenib in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a common human malignancy. Physcion is a naturally occurring anthraquinone derivative found in plant and marine sources. Our previous studies have indicated that physcion could suppress tumor growth and induce apoptosis in HCC. This study was aimed to investigate the effect of a combination of physcion and sorafenib on HCC. Our findings indicated that physcion could significantly augment the antiproliferative and proapoptotic activities of sorafenib in vitro and in vivo. Mechanistically, the synergistic effect correlates with physcion-induced suppression of Notch3/AKT signaling. This preclinical evidence highlights the potential application of physcion in the treatment of HCC. Anat Rec, 302:2171-2177, 2019. © 2019 American Association for Anatomy.

Use of Physcion to Improve Atopic Dermatitis-Like Skin Lesions through Blocking of Thymic Stromal Lymphopoietin

Physcion is well known for the treatment of carcinoma. However, the therapeutic effect of physcion on atopic dermatitis (AD) through the inhibition of thymic stromal lymphopoietin (TSLP) level remains largely unknown. In this study, we investigated the anti-AD effect of physcion using HMC-1 cells, splenocytes, and a murine model. Treatment with physcion decreased production and mRNA expression levels of TSLP, IL-6, TNF-ɑ, and IL-1β in activated HMC-1 cells. Physcion reduced the expression levels of RIP2/caspase-1 and phospho (p)ERK/pJNK/pp38 in activated HMC-1 cells. Physcion suppressed the expression levels of pIKKβ/NF-κB/pIkB in activated HMC-1 cells. Moreover, physcion attenuated the production levels of TSLP, IL-4, IL-6, TNF-, and IFN-γ from activated splenocytes. Oral administration of physcion improved the severity of 2,4-dinitrochlorobenzene-induced AD-like lesional skin through reducing infiltration of inflammatory cells and mast cells, and the protein and mRNA levels of TSLP, IL-4, and IL-6 in the lesional skin tissues. Physcion attenuated histamine, IgE, TSLP, IL-4, IL-6, and TNF- levels in serum. In addition, physcion inhibited caspase-1 activation in the lesional skin tissues. These findings indicate that physcion could ameliorate AD-like skin lesions by inhibiting TSLP levels via caspase-1/MAPKs/NF-kB signalings, which would provide experimental evidence of the therapeutic potential of physcion for AD.

Health functions and structure-activity relationships of natural anthraquinones from plants

Anthraquinone compounds with the anthraquinone ring structure are widely found in traditional Chinese medicines and they are attracting a lot of attention due to their good pharmacological activity. Diversities of anthraquinones depend on their chemical structures, such as the number of anthraquinone rings and the substituents; what's more, the difference in chemical structure determines the difference in physiological activity. Based on results of previous studies, this review summarizes several natural anthraquinones identified from Chinese herbal medicines and their physiological activities including anti-cancer, anti-pathogenic microorganisms, anti-inflammatory, anti-oxidation, anti-osteoporosis, anti-depression, and anti-constipation. The source, effect, model, and action mechanism of the active anthraquinones are described in detail, from which their structure-activity relationship is summarized. By analyzing the relationship between anthraquinone structure and function, we found that, on the whole structure, the anthraquinone ring and anthraquinone glycosides have significant anticancer activity and anti-constipation activity, while for their substituents, anthraquinones substituted by alizarin have significant antioxidant activity and the polarity of the substituents is closely related to their antibacterial activities.

A Cell-Based Metabonomics Approach to Investigate the Varied Influences of Chrysophanol-8-O-β-D-Glucoside With Different Concentrations on L-02 Cells

In this study, the effects of different concentrations of chrysophanol-8-O-β-D-glucoside (C-8-O-β-D-glu) on L-02 liver cells were analyzed by high content analysis (HCA) and metabonomics to explore the potential mechanism involved. The results showed that low concentrations (12 and 24 μM) of C-8-O-β-D-glu increased the cells viability significantly, while high concentration (96 μM) showed significant cytotoxicity on L-02 cells. HCA was applied to analyze the changes of nuclei and mitochondria after the cells being exposed to C-8-O-β-D-glu for 24 h. The results showed high concentration (96 μM) of C-8-O-β-D-glu significantly reduced the number of living cells, increased average nucleus area, DNA content and mitochondrial membrane potential (MMP). Then non-target metabonomics was carried out to identify potential biomarkers and metabolic pathways of L-02 cells impacted by C-8-O-β-D-glu. Eleven important potential biomarkers associated with four metabolic pathways were identified in this analysis. Dysregulation of alanine, aspartate and glutamate metabolism were observed in both LCG and HCG. In addition, low concentration (24 μM) of C-8-O-β-D-glu would impact arginine and proline metabolism. High concentration (96 μM) of C-8-O-β-D-glu would impact phenylalanine metabolism and beta-alanine metabolism. Alanine, aspartate and glutamate metabolism, arginine and proline metabolism, phenylalanine metabolism, beta-alanine metabolism were involved in different effects of C-8-O-β-D-glu on L-02 cells.

Aloe-emodin induces apoptosis in human oral squamous cell carcinoma SCC15 cells

Background

Oral and pharyngeal cancer is the most common malignant human cancers. Chemotherapy is an effective approach for anti-oral cancer therapy, while the drug tolerance and resistance remain a problem for oral cancer patients. Aloe-emodin, rhein and physcion are classified as anthraquinones, which are the main pharmacodynamic ingredients of Rheum undulatum L.. This study was undertaken to investigate whether aloe-emodin, rhein and physcion show inhibiting growth and inducing apoptosis in oral squamous cell carcinoma SCC15 cells. We found that aloe-emodin show inhibiting growth and inducing apoptosis in oral squamous cell carcinoma SCC15 cells, we also investigated the underlying mechanisms of apoptosis induced by aloe-emodin.

Methods

Thiazolyl blue tetrazolium bromide (MTT) test was used to detect cell proliferation. Cell apoptosis was detected by flow cytometry. We also used western blot analysis to detect the potential mechanisms of apoptosis.

Results

Aloe-emodin, rhein and physcion inhibit the proliferation of SCC15 cells and the order of inhibition level are aloe-emodin > Rhein > Physcion, the half maximal inhibitory concentrations (IC₅₀) value of aloe-emodin was 60.90 μM at 48 h of treatment. Aloe-emodin treatment resulted in a time- and dose-dependent decrease in cell viability and increased the apoptotic cell ratio. The results of western blotting showed the expression levels of caspase-9 and caspase-3 proteins increased following aloe-emodin treatment.

Conclusions

Our results revealed that aloe-emodin treatment could inhibit cell viability of SCC15 cells and the potential mechanism of inhibition might be through the induction of apoptosis by regulation of the expression levels of caspase-9 and caspase-3. This indicates that aloe-emodin may be a good agent for anti-oral cancer drug exploring.

Physcion induces apoptosis through triggering endoplasmic reticulum stress in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common and aggressive malignancies. The current study aimed to investigate the effect of physcion, a major active ingredient in several traditional herbal medicinal plants, for the treatment of HCC. Our data showed that physcion markedly induced apoptosis in human HCC cell lines Huh7 and Bel7402. The pro-apoptotic role of physcion on HCC cells was mediated by mitochondria dysfunction, which was caused by activation of endoplasmic reticulum(ER) stress. Moreover, our findings revealed that physcion stimulated ER stress by activating AMPK signaling. Besides in HCC cell lines, the anti-cancer activity of physcion was also examined in a xenograft mice model, which showed that physcion could significantly suppressed tumor growth. In conclusion, our results indicated that physcion can be considered as a potential chemotherapeutic agent in the treatment of HCC.

Advances in bio-active constituents, pharmacology and clinical applications of rhubarb

Rhubarb is one of the most ancient, commonly used and important herbs in Chinese medicine. The modern researches of rhubarb clarified the efficacies, ingredients and mechanisms in a more scientific and rigorous way. The main chemical compositions of rhubarb include anthraquinones, anthrones, stilbenes, tannins, polysaccharides etc. These compositions show extensive pharmacological activities including regulating gastrointestinal, anticancer, antimicrobial, hepatoprotective, anti-inflammatory, protecting cardiovascular, cerebrovascular and so on. This paper reviews the recent studies on the active ingredients, pharmacological effects, clinical application and functional mechanism.

Physcion blocks cell cycle and induces apoptosis in human B cell precursor acute lymphoblastic leukemia cells by downregulating HOXA5

Acute lymphoblastic leukemia (ALL) presents the most common type of malignancy in children and ranks the third most common cancer in adults. This study is aimed to investigate the anti-leukemia activity of physcion in ALL. Our results have showed that physcion could significantly suppress cell growth, induce apoptosis and blocked cell cycle progression in vitro. Mechanistically, we found that physcion downregulated the expression of HOXA5, which is responsible for the anti-leukemia activity of physcion. To verify this finding, siRNA targeting HOXA5 and overexpressing plasmid were used to repress HOXA5 expression and introduce ectopic overexpression of HOXA5 in ALL cell lines, respectively. Our results showed that overexpression of HOXA5 significantly abrogated the inducing effect of physcion on apoptosis and cell cycle blockasde. In contrast, knockdown of HOXA5 by siRNA enhanced the anti-tumor effect of physcion on ALL cell lines. Our results provided experimental base for the use of physcion in the treatment of ALL.

Physcion, a naturally occurring anthraquinone derivative, induces apoptosis and autophagy in human nasopharyngeal carcinoma

AIM

Physcion is a major bioactive ingredient in the traditional Chinese medicine Radix et Rhizoma Rhei, which has an anthraquinone chemical structure and exhibits a variety of pharmacological activities including laxative, hepatoprotective, anti-inflammatory, anti-microbial and anti-proliferative effects. In this study we investigated the effect of physcion on human nasopharyngeal carcinoma in vitro and in vivo, as well as the mechanisms underlying the anti-tumor action.

METHODS

The nasopharyngeal carcinoma cell line CNE2 was treated with physcion, and cell viability was detected using MTT and colony formation assays. Flow cytometry was used to assess the cell cycle arrest, mitochondrial membrane potential loss, apoptosis, autophagy and intracellular ROS generation. Apoptotic cell death was also confirmed by a TUNEL assay. The expression of target or marker molecules was determined using Western blotting. The activity of caspase-3, 8, and 9 was detected with an ELISA kit. A xenograft murine model was used to evaluate the in vivo anti-tumor action of physcion, the mice were administered physcion (10, 20 mg·kg-1·d-1, ip) for 30 d.

RESULTS

Treatment with physcion (5, 10, and 20 μmol/L) dose-dependently suppressed the cell viability and colony formation in CNE2 cells. Physcion (10 and 20 μmol/L) dose-dependently blocked cell cycle progression at G1 phase and induced both caspase-dependent apoptosis and autophagy in CNE2 cells. Furthermore, physcion treatment induced excessive ROS generation in CNE2 cells, and subsequently disrupted the miR-27a/ZBTB10 axis, resulting in repression of the transcription factor Sp1 that was involved in physcion-induced apoptosis and autophagy. Moreover, physcion-induced autophagy acted as a pro-apoptotic factor, and possibly contributed to physcion-induced apoptosis. In the xenograft murine model, administration of physcion dose-dependently suppressed the tumor growth without affecting the body weight. Furthermore, the anti-tumor effects of physcion were correlated with downregulation of Sp1 and suppression of miR-27a in the tumor tissues.

CONCLUSION

Physcion induces apoptosis and autophagy in human nasopharyngeal carcinoma by targeting Sp1, which was mediated by ROS/miR-27a/ZBTB10 signaling. The results suggest that physcion is a promising candidate for the treatment of human nasopharyngeal carcinoma.

Upregulation of Human ST8Sia VI (α2,8-Sialyltransferase) Gene Expression by Physcion in SK-N-BE(2)-C Human Neuroblastoma Cells

In this research, we firstly demonstrated that physcion, an anthraquinone derivative, specifically increased the expression of the human α2,8-sialyltransferase (hST8Sia VI) gene in SK-N-BE(2)-C human neuroblastoma cells. To establish the mechanism responsible for the up-regulation of hST8Sia VI gene expression in physcion-treated SK-N-BE(2)-C cells, the putative promoter region of the hST8Sia VI gene was functionally characterized. Promoter analysis with serially truncated fragments of the 5′-flanking region showed that the region between −320 and −240 is crucial for physcion-induced transcription of hST8Sia VI in SK-N-BE(2)-C cells. Putative binding sites for transcription factors Pax-5 and NF-Y are located at this region. The Pax-5 binding site at −262 to −256 was essential for the expression of the hST8Sia VI gene by physcion in SK-N-BE(2)-C cells. Moreover, the transcription of hST8Sia VI induced by physcion in SK-N-BE(2)-C cells was inhibited by extracellular signal-regulated protein kinase (ERK) inhibitor U0126 and p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580, but not c-Jun N-terminal kinase (JNK) inhibitor SP600125. These results suggest that physcion upregulates hST8Sia VI gene expression via ERK and p38 MAPK pathways in SK-N-BE(2)-C cells.