Licoricidin inhibits the growth of SW480 human colorectal adenocarcinoma cells in vitro and in vivo by inducing cycle arrest, apoptosis and autophagy

Potential of Glycyrrhiza in the prevention of colitis-associated colon cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Glycyrrhiza, a legume native to the Mediterranean region, has a long history of ethnomedicinal use in China. Due to its antiviral, antibacterial, anti-inflammatory, antioxidant, antitumor, anti-ulcer, and hepatoprotective properties, Glycyrrhiza is widely utilized in the treatment of gastrointestinal disorders.

THE AIM OF THE REVIEW

The specific mechanisms of the main active constituents of glycyrrhiza in the treatment of inflammatory bowel disease, precancerous lesions and colorectal cancer at all stages of the colitis-associated colon cancer "Inflammation-Dysplasia-Cancer" sequence, as well as its pharmacokinetics, toxicology, formulation improvements, and application studies, are reviewed to provide new insights and perspectives on glycyrrhiza as a dietary supplement to treat and prevent colitis-associated colon cancer.

MATERIALS AND METHODS

Information on Glycyrrhiza was retrieved from electronic databases, including PubMed and Web of Science.

RESULTS

Glycyrrhiza is a well-established medicinal plant with significant potential for applications in both the food and pharmaceutical industries. Over 400 active constituents have been identified in Glycyrrhiza, including terpenoids, flavonoids, isoflavones, coumarins, and polyphenols. Numerous studies have demonstrated that Glycyrrhiza and its active compounds can inhibit the "Inflammation-Dysplasia-Cancer" progression of colitis-associated colon cancer by mitigating inflammatory bowel disease, reducing the number of intestinal precancerous lesions, and counteracting colorectal cancer. Furthermore, derivatives and nanocarriers are crucial for the effective treatment of colitis-associated colon cancer using Glycyrrhiza and its active constituents.

CONCLUSION

In conclusion, Glycyrrhiza is a plant with both medicinal and nutritional value, making it a potential food ingredient and dietary supplement for the treatment of colitis-associated colon cancer.

Wighteone, a prenylated flavonoid from licorice, inhibits growth of SW480 colorectal cancer cells by allosteric inhibition of Akt

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice is a frequently used herbal medicine worldwide, and is used to treat cough, hepatitis, cancer and influenza in clinical practice of traditional Chinese medicine. Modern pharmacological studies indicate that prenylated flavonoids play an important role in the anti-tumor activity of licorice, especially the tumors in stomach, lung, colon and liver. Wighteone is one of the main prenylated flavonoids in licorice, and its possible effect and target against colorectal cancer have not been investigated.

AIM OF THE STUDY

This study aimed to investigate the anti-colorectal cancer effect and underlying mechanism of wighteone.

MATERIALS AND METHODS

SW480 human colorectal cancer cells were used to evaluate the in vitro anti-colorectal cancer activity and Akt regulation effect of wighteone by flow cytometry, phosphoproteomic and Western blot analysis. Surface plasmon resonance (SPR) assay, molecular docking and dynamics simulation, and kinase activity assay were used to investigate the direct interaction between wighteone and Akt. A nude mouse xenograft model with SW480 cells was used to verify the in vivo anti-colorectal cancer activity of wighteone.

RESULTS

Wighteone inhibited phosphorylation of Akt and its downstream kinases in SW480 cells, which led to a reduction in cell viability. Wighteone had direct interaction with both PH and kinase domains of Akt, which locked Akt in a "closed" conformation with allosteric inhibition, and Gln79, Tyr272, Arg273 and Lys297 played the most critical role due to their hydrogen bond and hydrophobic interactions with wighteone. Based on Akt overexpression or activation in SW480 cells, further mechanistic studies suggested that wighteone-induced Akt inhibition led to cycle arrest, apoptosis and autophagic death of SW480 cells. Moreover, wighteone exerted in vivo anti-colorectal cancer effect and Akt inhibition activity in the nude mouse xenograft model.

CONCLUSION

Wighteone could inhibit growth of SW480 cells through allosteric inhibition of Akt, which led to cell cycle arrest, apoptosis and autophagic death. The results contributed to understanding of the anti-tumor mechanism of licorice, and also provided a rationale to design novel Akt allosteric inhibitors for the treatment of colorectal cancer.

Plant-derived natural compounds: A new frontier in inducing immunogenic cell death for cancer treatment

Immunogenic cell death (ICD) can activate adaptive immune response in the host with normal immune system. Some synthetic chemotherapeutic drugs and natural compounds have shown promising results in cancer treatment by triggering the release of damage-associated molecules (DAMPs) to trigger ICD. However, most chemotherapeutic drugs exhibit non-selective cytotoxicity and may also induce and promote metastasis, thereby significantly reducing their clinical efficacy. Among the natural compounds that can induce ICD, plant-derived compounds account for the largest proportion, which are of increasing value in the treatment of cancer. Understanding which plant-derived natural compounds can induce ICD and how they induce ICD is crucial for developing strategies to improve chemotherapy outcomes. In this review, we focus on the recent findings regarding plant-derived natural compounds that induce ICD according to the classification of flavonoids, alkaloids, glycosides, terpenoids and discuss the potential mechanisms including endoplasmic reticulum (ER) stress, DNA damage, apoptosis, necroptosis autophagy, ferroptosis. In addition, plant-derived natural compounds that can enhance the ICD induction ability of conventional therapies for cancer treatment is also elaborated. The rational use of plant-derived natural compounds to induce ICD is helpful for the development of new cancer treatment methods.

Amicis Omnia Sunt Communia: NF-κB Inhibition as an Alternative to Overcome Osteosarcoma Heterogeneity

Tumor heterogeneity poses a significant challenge in osteosarcoma (OS) treatment. In this regard, the "omics" era has constantly expanded our understanding of biomarkers and altered signaling pathways (i.e., PI3K/AKT/mTOR, WNT/β-catenin, NOTCH, SHH/GLI, among others) involved in OS pathophysiology. Despite different players and complexities, many commonalities have been described, among which the nuclear factor kappa B (NF-κB) stands out. Its altered activation is pervasive in cancer, with pleiotropic action on many disease-relevant traits. Thus, in the scope of this article, we highlight the evidence of NF-κB dysregulation in OS and its integration with other cancer-related pathways while we summarize the repertoire of compounds that have been described to interfere with its action. In silico strategies were used to demonstrate that NF-κB is closely coordinated with other commonly dysregulated signaling pathways not only by functionally interacting with several of their members but also by actively participating in the regulation of their transcription. While existing inhibitors lack selectivity or act indirectly, the therapeutic potential of targeting NF-κB is indisputable, first for its multifunctionality on most cancer hallmarks, and secondly, because, as a common downstream effector of the many dysregulated pathways influencing OS aggressiveness, it turns complex regulatory networks into a simpler picture underneath molecular heterogeneity.

A Comprehensive Review of Licorice: The Preparation, Chemical Composition, Bioactivities and Its Applications

Licorice (Glycyrrhiza) is a medicinal and food homologue of perennial plants derived from the dried roots and rhizomes of the genus Glycyrrhiza in the legume family. In recent years, the comprehensive utilization of licorice resources has attracted people's attention. It is widely utilized to treat diseases, health food products, food production, and other industrial applications. Furthermore, numerous bioactive components of licorice are found using advanced extraction processes, which mainly include polyphenols (flavonoids, dihydrostilbenes, benzofurans, and coumarin), triterpenoids, polysaccharides, alkaloids, and volatile oils, all of which have been reported to possess a variety of pharmacological characteristics, including anti-oxidant, anti-inflammatory, antibacterial, antiviral, anticancer, neuroprotective, antidepressive, antidiabetic, antiparasitic, antisex hormone, skin effects, anticariogenic, antitussive, and expectorant activities. Thereby, all of these compounds promote the development of novel and more effective licorice-derived products. This paper reviews the progress of research on extraction techniques, chemical composition, bioactivities, and applications of licorice to provide a reference for further development and application of licorice in different areas.

Induction of immunogenic cell death effect of licoricidin in cervical cancer cells by enhancing endoplasmic reticulum stress-mediated high mobility group box 1 expression

Licoricidin (LCD) is an activity compound of the roots of Glycyrrhiza uralensis, which has therapeutic efficacy, including anti-virus, anti-cancer, and enhanced immunity in Traditional Chinese Medicine. Herein, this study aimed to clarify the effect of LCD on cervical cancer cells. In the present study, we found that LCD significantly inhibited cell viability via inducing cell apoptosis and companies with cleaved-PARP protein expression and caspase-3/-9 activity. Cell viability was markedly reversed these effects by pan-caspase inhibitor Z-VAD-FMK treatment. Furthermore, we showed that LCD-induced ER (endoplasmic reticulum) stress triggers upregulating the protein level of GRP78 (Bip), CHOP, and IRE1α, and subsequently confirmed the mRNA level by quantitative real-time polymerase chain reaction. In addition, LCD exhibited the release of danger-associated molecular patterns from cervical cancer cells, such as the release of high-mobility group box 1 (HMGB1), secretion of ATP, and exposure of calreticulin (CRT) on the cell surface, which led to immunogenic cell death (ICD). These results provide a novel foundation that LCD induces ICD via triggering ER stress in human cervical cancer cells. LCD might be an ICD inducer of immunotherapy in progressive cervical cancer.

Chitosan nanoparticles efficiently enhance the dispersibility, stability and selective antibacterial activity of insoluble isoflavonoids

Natural isoflavonoids have attracted much attention in the treatment of oral bacterial infections and other diseases due to their excellent antibacterial activity and safety. However, their poor water solubility, instability and low bioavailability seriously limited the practical application. In this study, licoricidin-loaded chitosan nanoparticles (LC-CSNPs) were synthesized by self-assembly for improving the dispersion of licoricidin (LC) and strengthening antibacterial and anti-biofilm performance. Compared to free LC, the minimum inhibitory concentration of LC-CSNPs against Streptococcus mutans decreased >2-fold to 26 μg/mL, and LC-CSNPs could ablate 70 % biofilms at this concentration. The enhanced antibacterial activity was mainly attributed to the spontaneous surface adsorption of LC-CSNPs on cell membranes through electrostatic interactions. More valuably, LC-CSNPs had no inhibitory effect on the growth of probiotic. Mechanism study indicated that LC-CSNPs altered the transmembrane potential to cause bacterial cells in a hyperpolarized state, generating ROS to cause cells damage and eventually apoptosis. This work demonstrated that the chitosan-based nanoparticles have great potential in enhancing the dispersibility and antibacterial activity of insoluble isoflavonoids, offering a promising therapeutic strategy for oral infections.

Autophagy and the Insulin-like Growth Factor (IGF) System in Colonic Cells: Implications for Colorectal Neoplasia

Colorectal cancer (CRC) is one of the most common human malignancies worldwide. Along with apoptosis and inflammation, autophagy is one of three important mechanisms in CRC. The presence of autophagy/mitophagy in most normal mature intestinal epithelial cells has been confirmed, where it has mainly protective functions against reactive oxygen species (ROS)-induced DNA and protein damage. Autophagy regulates cell proliferation, metabolism, differentiation, secretion of mucins and/or anti-microbial peptides. Abnormal autophagy in intestinal epithelial cells leads to dysbiosis, a decline in local immunity and a decrease in cell secretory function. The insulin-like growth factor (IGF) signaling pathway plays an important role in colorectal carcinogenesis. This is evidenced by the biological activities of IGFs (IGF-1 and IGF-2), IGF-1 receptor type 1 (IGF-1R) and IGF-binding proteins (IGF BPs), which have been reported to regulate cell survival, proliferation, differentiation and apoptosis. Defects in autophagy are found in patients with metabolic syndrome (MetS), inflammatory bowel diseases (IBD) and CRC. In neoplastic cells, the IGF system modulates the autophagy process bidirectionally. In the current era of improving CRC therapies, it seems important to investigate the exact mechanisms not only of apoptosis, but also of autophagy in different populations of tumor microenvironment (TME) cells. The role of the IGF system in autophagy in normal as well as transformed colorectal cells still seems poorly understood. Hence, the aim of the review was to summarize the latest knowledge on the role of the IGF system in the molecular mechanisms of autophagy in the normal colon mucosa and in CRC, taking into account the cellular heterogeneity of the colonic and rectal epithelium.

Chemical analysis of the Chinese herbal medicine licorice (Gan-Cao): An update review

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice, called Gan-Cao in China, is one of the most popular traditional herbal medicines. It is derived from the dried roots and rhizomes of Glycyrrhiza uralensis, G. glabra, and G. inflata. Licorice is recorded in the pharmacopoeias of China, Japan, US, and Europe.

AIM

This review updates research progress of licorice from the perspectives of chemical analysis, quality evaluation, drug metabolism, and pharmacokinetic studies from 2009 to April 2022.

MATERIALS AND METHODS

Both English and Chinese literatures were collected from databases including PubMed, Elsevier, Web of Science, and CNKI (Chinese). Licorice, extraction, structural characterization/identification, quality control, metabolism, and pharmacokinetics were used as keywords.

RESULTS

Newly developed analytical methods, including LC/UV, 2DLC, LC/MS, GC/MS, and mass spectrometry imaging (MSI) for chemical analysis of licorice were summarized.

CONCLUSION

This review provides a comprehensive summary on chemical analysis of licorice.

Natural Products as Anticancer Agents: Current Status and Future Perspectives

Natural products have been an invaluable and useful source of anticancer agents over the years. Several compounds have been synthesized from natural products by modifying their structures or by using naturally occurring compounds as building blocks in the synthesis of these compounds for various purposes in different fields, such as biology, medicine, and engineering. Multiple modern and costly treatments have been applied to combat cancer and limit its lethality, but the results are not significantly refreshing. Natural products, which are a significant source of new therapeutic drugs, are currently being investigated as potential cytotoxic agents and have shown a positive trend in preclinical research and have prompted numerous innovative strategies in order to combat cancer and expedite the clinical research. Natural products are becoming increasingly important for drug discovery due to their high molecular diversity and novel biofunctionality. Furthermore, natural products can provide superior efficacy and safety due to their unique molecular properties. The objective of the current review is to provide an overview of the emergence of natural products for the treatment and prevention of cancer, such as chemosensitizers, immunotherapeutics, combinatorial therapies with other anticancer drugs, novel formulations of natural products, and the molecular mechanisms underlying their anticancer properties.

Licoricidin combats gastric cancer by targeting the ICMT/Ras pathway in vitro and in vivo

Licoricidin, a type of isoflavonoid, is extracted from the root of Glycyrrhiza glabra. It has been widely proven that licoricidin possesses multiple biological activities, including anti-cancer effects and a powerful antimicrobial effect against Helicobacter pylori (H. pylori). However, the exact mechanism of licoricidin against gastric cancer remains unclear. In this study, we comprehensively explored the effects of licoricidin on MGC-803 gastric cancer cells in vitro and in vivo and further elucidated its mechanism of action. Our results revealed that licoricidin exhibited multiple anti-gastric cancer activities, including suppressing proliferation, inducing apoptosis, arresting the cell cycle in G₀/G₁ phase, and inhibiting the migration and invasion abilities of MGC-803 gastric cancer cells. In addition to this, a total of 5861 proteins were identified by quantitative proteomics research strategy of TMT labeling, of which 19 differential proteins (two upregulated and 17 downregulated) were screened out. Combining bioinformatics analyses and the reported roles in cancer progression of the 19 proteins, we speculated that isoprenyl carboxyl methyltransferase (ICMT) was the most likely target of licoricidin. Western blot assays and IHC assays subsequently proved that licoricidin significantly downregulated the expression of ICMT, both in MGC-803 cells and in xenograft tumors. Moreover, licoricidin effectively reduced the level of active Ras-GTP and blocked the phosphorylation of Raf and Erk, which may be involved in its anti-gastric cancer effects. In summary, we first demonstrated that licoricidin exerted favorable anti-gastric cancer activities via the ICMT/Ras pathway, which suggests that licoricidin, as a natural product, could be a novel candidate for the management of gastric cancer.

Diprenylated flavonoids from licorice induce death of SW480 colorectal cancer cells by promoting autophagy: Activities of lupalbigenin and 6,8-diprenylgenistein

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice is a well-known herbal medicine, and we previously found that several licorice prenylated flavonoids could cause death of SW480 colorectal cancer cells by promoting autophagy. Given many kinds of prenylated flavonoids in licorice, the activities of other compounds deserve further investigation. In addition, the contribution of isoprenyl groups on the autophagy promotion activities has not been clarified.

AIM OF THE STUDY

This study aimed to investigate whether lupalbigenin (LPB) and 6,8-diprenylgenistein (DPG), two licorice diprenylated flavonoids, could induce autophagic cell death of SW480 cells, and clarify the contribution of isoprenyl groups.

MATERIALS AND METHODS

Cytotoxic activities of LPB and DPG were tested by using an MTT method, and apoptosis induction effects were evaluated by PI-Annexin V staining-based flow cytometry and protein levels of caspase-3 and PARP-1. Autophagy promotion effects of LPB and DPG were assessed by protein levels of LC3, p62, Akt and mTOR as well as number of autophagosomes in cells, and autophagy inhibitor chloroquine (CQ) was involved to identify the role of autophagy on LPB or DPG-caused death of SW480 cells. In addition, two groups of structurally similar diprenylated, mono-prenylated and free flavonoids were obtained from licorice, which were used to investigate the contribution of isoprenyl groups on their autophagy promotion activities.

RESULTS

Both LPB and DPG significantly induced apoptosis of SW480 cells with strong cytotoxic activities, and meanwhile, they also promoted autophagy probably through the Akt/mTOR signaling pathway. Further studies indicated that LPB and DPG could induce autophagic cell death of SW480 cells. Moreover, isoprenyl groups contributed mainly to the cytotoxic and autophagy promotion activities of licorice prenylated flavonoids.

CONCLUSION

This study reported for the first time that licorice diprenylated flavonoids LPB and DPG induced death of SW480 cells by promoting autophagy, which was mainly attributed to the isoprenyl groups. The results provided theoretical basis for researches on anti-colorectal cancer drugs and their structural modification.

Targeting autophagy in colorectal cancer: An update on pharmacological small-molecule compounds

Autophagy, an evolutionarily highly conserved cellular degradation process, plays the Janus role (either cytoprotective or death-promoting) in colorectal cancer, so the targeting of several key autophagic pathways with small-molecule compounds may be a new therapeutic strategy. In this review, we discuss autophagy-associated cell death pathways and key cytoprotective autophagy pathways in colorectal cancer. Moreover, we summarize a series of small-molecule compounds that have the potential to modulate autophagy-associated cell death or cytoprotective autophagy for therapeutic purposes. Taken together, these findings demonstrate the Janus role of autophagy in colorectal cancer, and shed new light on the exploitation of a growing number of small-molecule compounds to target autophagy in future cancer drug discovery.

Anticancer properties of arylchromenes and arylchromans: an overview

Cancers are a set of pathologies originated by cells that have the ability to divide and multiply uncontrollably, associated with the capacity to invade and colonize adjacent tissues. Chemotherapy is one of the main approaches of treatment for cancer patients. Despite of the numerous antineoplastic drugs available, cancer cannot be cured; particularly at the late stages deprived of any side effect. Arylchromenes and arylchromans are a group of small molecules, of natural or synthetic origin, of great interest as prototypes for the drug development, especially against cancer. In this chapter, we will present the antineoplastic activity studies of the most promising examples of these arylchromenes and arylchroman derivatives.

Quercetin Attenuates Podocyte Apoptosis of Diabetic Nephropathy Through Targeting EGFR Signaling

Podocytes injury is one of the leading causes of proteinuria in patients with diabetic nephropathy (DN), and is accompanied by podocytes apoptosis and the reduction of podocyte markers such as synaptopodin and nephrin. Therefore, attenuation of podocyte apoptosis is considered as an effective strategy to prevent the proteinuria in DN. In this study, we evaluated the anti-podocyte-apoptosis effect of quercetin which is a flavonol compound possessing an important role in prevention and treatment of DN and verified the effect by using db/db mice and high glucose (HG)-induced mouse podocytes (MPs). The results show that administration of quercetin attenuated the level of podocyte apoptosis by decreasing the expression of pro-apoptotic protein Bax, cleaved caspase 3 and increasing the expression of anti-apoptotic protein Bcl-2 in the db/db mice and HG-induced MPs. Furthermore, epidermal growth factor receptor (EGFR) was predicted to be the potential physiological target of quercetin by network pharmacology. In vitro and vivo experiments confirmed that quercetin inhibited activation of the EGFR signaling pathway by decreasing phosphorylation of EGFR and ERK1/2. Taken together, this study demonstrates that quercetin attenuated podocyte apoptosis through inhibiting EGFR signaling pathway, which provided a novel approach for further research of the mechanism of quercetin in the treatment of DN.

Synthetic and Naturally Occurring Heterocyclic Anticancer Compounds with Multiple Biological Targets

Cancer is a complex group of diseases initiated by abnormal cell division with the potential of spreading to other parts of the body. The advancement in the discoveries of omics and bio- and cheminformatics has led to the identification of drugs inhibiting putative targets including vascular endothelial growth factor (VEGF) family receptors, fibroblast growth factors (FGF), platelet derived growth factors (PDGF), epidermal growth factor (EGF), thymidine phosphorylase (TP), and neuropeptide Y4 (NY4), amongst others. Drug resistance, systemic toxicity, and drug ineffectiveness for various cancer chemo-treatments are widespread. Due to this, efficient therapeutic agents targeting two or more of the putative targets in different cancer cells are proposed as cutting edge treatments. Heterocyclic compounds, both synthetic and natural products, have, however, contributed immensely to chemotherapeutics for treatments of various diseases, but little is known about such compounds and their multimodal anticancer properties. A compendium of heterocyclic synthetic and natural product multitarget anticancer compounds, their IC50, and biological targets of inhibition are therefore presented in this review.

Microfluidic Tandem Mechanical Sorting System for Enhanced Cancer Stem Cell Isolation and Ingredient Screening

Robust isolation of cancer stem cells (CSCs) in a high-throughput, label-free manner is critical for understanding tumor heterogeneity and developing therapeutic strategies targeting CSCs. Cell-mechanics-based microfluidic sorting systems provide efficient and specific platforms for investigation of stem cell-like characteristics on the basis of cell deformability and cell-substrate adhesion properties. In the present study, a microfluidic tandem mechanical sorting system is developed to enrich CSCs with high flexibility and low adhesive capacity. In the integrated microfluidic system, cancer cells are driven by hydrodynamic forces to flow continuously through two featured devices, which are functionalized with sequentially variable microbarriers and surface-coated fluid mixing microchannels, respectively. Collected deformable and low-adhesive cancer cells exhibit enhanced stem cell-like properties with higher stemness and metastasis capacity both in vitro and in vivo, compared with each single device separation. Using these devices, bioactive natural compound screening targeting CSCs is performed and a potent therapeutic compound isoliquiritigenin from licorice is identified to inhibit the lung cancer stem cell phenotype. Taken together, this microfluidic tandem mechanical sorting system can facilitate drug screening targeting CSCs and the analysis of signals regulating CSC function in drug resistance.

ACNPD: The Database for Elucidating the Relationships Between Natural Products, Compounds, Molecular Mechanisms, and Cancer Types

Objectives: Cancer is well-known as a collection of diseases of uncontrolled proliferation of cells caused by mutated genes which are generated by external or internal factors. As the mechanisms of cancer have been constantly revealed, including cell cycle, proliferation, apoptosis and so on, a series of new emerging anti-cancer drugs acting on each stage have also been developed. It is worth noting that natural products are one of the important sources for the development of anti-cancer drugs. To the best of our knowledge, there is not any database summarizing the relationships between natural products, compounds, molecular mechanisms, and cancer types.

Materials and methods: Based upon published literatures and other sources, we have constructed an anti-cancer natural product database (ACNPD) (http://www.acnpd-fu.com/). The database currently contains 521 compounds, which specifically refer to natural compounds derived from traditional Chinese medicine plants (derivatives are not considered herein). And, it includes 1,593 molecular mechanisms/signaling pathways, covering 10 common cancer types, such as breast cancer, lung cancer and cervical cancer.

Results: Integrating existing data sources, we have obtained a large amount of information on natural anti-cancer products, including herbal sources, regulatory targets and signaling pathways. ACNPD is a valuable online resource that illustrates the complex pharmacological relationship between natural products and human cancers.

Conclusion: In summary, ACNPD is crucial for better understanding of the relationships between traditional Chinese medicine (TCM) and cancer, which is not only conducive to expand the influence of TCM, but help to find more new anti-cancer drugs in the future.

Isoangustone A induces autophagic cell death in colorectal cancer cells by activating AMPK signaling

Phytochemicals, especially flavonoids, have been widely investigated for their diversified pharmacological activities including anticancer activities. Previously we identified isoangustone A from licorice-derived compounds as a potent inducer of cell death. In the present study, the exact mechanism by which isoangustone A induced cell death was further investigated, with autophagy as an indispensible part of this process. Isoangustone A treatment activated autophagic signaling and induced a complete autophagic flux in colorectal cancer cells. Knockdown of ATG5 or pre-treatment with autophagy inhibitors significantly reversed isoangustone A-induced apoptotic signaling and loss of cell viability, suggesting autophagy plays an important role in isoangustone A-induced cell death. Isoangustone A inhibited Akt/mTOR signaling, and overexpressing of a constitutively activated Akt mildly suppressed isoangustone A-induced cell death. More importantly, isoangustone A inhibited cellular ATP level and activated AMPK, and pre-treatment with AMPK inhibitor or overexpression of dominant negative AMPKα2 significantly reversed isoangustone A-induced autophagy and cell death. Further study shows isoangustone A dose-dependently inhibited mitochondrial respiration, which could be responsible for isoangustone A-induced activation of AMPK. Finally, isoangustone A at a dosage of 10 mg/kg potently activated AMPK and autophagic signaling in and inhibited the growth of SW480 human colorectal xenograft in vivo. Taken together, induction of autophagy through activation of AMPK is an important mechanism by which isoangustone A inhibits tumor growth, and isoangustone A deserves further investigation as a promising anti-cancer agent.

Molecular mechanisms underlying the anticancer activities of licorice flavonoids

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice has been commonly used in traditional Chinese medicine for treatment of gastric, liver, and respiratory disease conditions for more than two thousand years. It is a major component of several Chinese patent medicines certificated by National Medical Products Administration that possess great anticancer activities.

AIM OF THE STUDY

To comprehensively summarize the anticancer activities of licorice flavonoids, explain the underlying molecular mechanisms, and assess their therapeutic potentials and side-effects.

METHODS

PubMed, Research Gate, Web of Science, Google Scholar, academic journals, and Science Direct were used as information sources, with the key words of "anticancer", "licorice", "flavonoids", and their combinations, mainly from 2000 to 2019.

RESULTS

Sixteen licorice flavonoids are found to possess anticancer activities. These flavonoids inhibit cancer cells through blocking cell cycle and regulating multiple signaling pathways. The major pathways targeted by licorice flavonoids include: the MAPK pathway, PI3K/AKT pathway, NF-κB pathway, death receptor - dependent extrinsic signaling pathway, and mitochondrial apoptotic pathway.

CONCLUSION

Licorice flavonoids are a group of versatile molecules that have pleiotropic effects on cell growth, survival and cell signaling. Many of the flavonoids possess inhibitory activities toward cancer cell growth and hence have a great therapeutic potential in cancer treatment. However, additional preclinical studies are still needed to assess their in vivo efficacy and possible toxicities. It is also imperative to evaluate the effects of licorice flavonoids on the metabolism of other drugs and explore the potential synergistic mechanism.

Discovery of thiosemicarbazone-containing compounds with potent anti-proliferation activity against drug-resistant K562/A02 cells

P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) is a major obstacle to successful chemotherapy for leukemia. In this study, a series of thiosemicarbazone-containing compounds (4a-b, 7a-q) were synthesized. Biological evaluation showed that the most active compound 7e displayed potent anti-leukemia activity against P-gp overexpressing drug-resistant K562/A02 cells, with an IC₅₀ value of 0.44 μM. Notably, compound 7e exhibited a selective killing effect on K562/A02 cells by dose-dependently increasing the intracellular levels of reactive oxygen species (ROS), thus exerting a potential collateral sensitivity (CS)-promoting effect in vitro. Moreover, compound 7e could inhibit HDAC1 and HDAC6, and induce the apoptosis of K562/A02 cells by increasing the expression of Bax, decreasing Bcl-2 protein level, and promoting the cleavage of caspase-3 and PARP, respectively. Overall, 7e may be a potential anti-cancer agent against drug-resistant myelogenous leukemia.

Assessment of Thiosemicarbazone-Containing Compounds as Potential Antileukemia Agents against P-gp Overexpressing Drug Resistant K562/A02 Cells

P-Glycoprotein (P-gp) overexpression is considered to be the leading cause of multidrug resistance (MDR) and failure of chemotherapy for leukemia. In this study, seventeen thiosemicarbazone-containing compounds were prepared and evaluated as potential antileukemia agents against drug resistant K562/A02 cell overexpressing P-gp. Among them, N-hydroxy-6-({(2E)-2-[(3-nitrophenyl)methylidene]hydrazinecarbothioyl}amino)hexanamide could significantly inhibit K562/A02 cells proliferation with an IC₅₀ value of 0.96 μM. Interestingly, N-hydroxy-6-({(2E)-2-[(3-nitrophenyl)methylidene]hydrazinecarbothioyl}amino)hexanamide could dose-dependently increase ROS levels of drug resistant K562/A02 cells, thus displaying a potential collateral sensitivity (CS)-inducing effect and selectively killing K562/A02 cells. Furthermore, N-hydroxy-6-({(2E)-2-[(3-nitrophenyl)methylidene]hydrazinecarbothioyl}amino)hexanamide possessed potent inhibitory effect on HDAC1 and HDAC6, and could promote K562/A02 cells apoptosis via dose-dependently increasing Bax expression, reducing Bcl-2 protein level, and inducing the cleavage of PARP and caspase3. These present findings suggest that N-hydroxy-6-({(2E)-2-[(3-nitrophenyl)methylidene]hydrazinecarbothioyl}amino)hexanamide might be a promising lead to discover novel antileukemia agents against P-gp overexpressing leukemic cells.

The anti-diabetic activity of licorice, a widely used Chinese herb

ETHNOPHARMACOLOGICAL RELEVANCE

A great deal of valuable experience has been accumulated in the traditional Chinese medicine (TCM) system for the treatment of "Xiaoke" disease which is known as diabetes mellitus now. As the most-commonly used Chinese herb, licorice has been used in TCM for more than two thousand years. It is often used in combination with other herbs to treat metabolic disorders, especially diabetes mellitus.

AIM OF THE STUDY

To summarize the characteristics, mechanisms, and clinical use of licorice and its active components for treating diabetes mellitus.

METHODS

PubMed, Web of Science, Research Gate, Science Direct, Google Scholar, and Academic Journals were used as information sources by the inclusion of the search terms 'diabetes', 'licorice', 'licorice extracts', 'flavonoids', 'triterpenoids', and their combinations, mainly from 2005 to 2019.

RESULTS

Licorice extracts, five flavonoids and three triterpenoids isolated from licorice possess great antidiabetic activities in vivo and in vitro. This was done by several mechanisms such as increasing the appetency and sensitivity of insulin receptor site to insulin, enhancing the use of glucose in different tissues and organs, clearing away the free radicals and resist peroxidation, correcting the metabolic disorder of lipid and protein, and improving microcirculation in the body. Multiple signaling pathways, including the PI3K/Akt, AMPK, AGE-RAGE, MAPK, NF-кB, and NLRP3 signaling pathways, are targets of the licorice compounds.

CONCLUSION

Licorice and its metabolites have a great therapeutic potential for the treatment of diabetes mellitus. However, a better understanding of their pharmacological mechanisms is needed for evaluating its efficacy and safety.

Transcriptome Profiling and Cytological Assessments for Identifying Regulatory Pathways Associated With Diorcinol N-Induced Autophagy in A3 Cells

Fungal secondary metabolites serve as a rich resource for exploring lead compounds with medicinal importance. Diorcinol N (DN), a fungal secondary metabolite isolated from an endophytic fungus, Arthrinium arundinis, exhibits robust anticancer activity. However, the anticancer mechanism of DN remains unclear. In this study, we examined the growth-inhibitory effect of DN on different human cancer cell lines. We found that DN decreased the viability of A3 T-cell leukemia cells in a time- and concentration-dependent manner. Transcriptome analysis indicated that DN modulated the transcriptome of A3 cells. In total, 9,340 differentially expressed genes were found, among which 4,378 downregulated genes and 4,962 upregulated genes were mainly involved in autophagy, cell cycle, and DNA replication. Furthermore, we demonstrated that DN induced autophagy, cell cycle arrest in the G1/S phase, and downregulated the expression of autophagy- and cell cycle-related genes in A3 cells. By labeling A3 cells with acridine orange/ethidium bromide, Hoechst 33,258, and monodansylcadaverine and via transmission electron microscopy, we found that DN increased plasma membrane permeability, structural disorganization, vacuolation, and autophagosome formation. Our study provides evidence for the mechanism of anticancer activity of DN in T-cell leukemia (A3) cells and demonstrates the promise of DN as a lead or even candidate molecule for the treatment of acute lymphoblastic leukemia.

Identification of a Novel c-Myc Inhibitor 7594-0037 by Structure-Based Virtual Screening and Investigation of Its Anti-Cancer Effect on Multiple Myeloma

Introduction

Multiple myeloma (MM) is an extremely malignant and incurable hematological cancer. Increased expression of the c-Myc oncoprotein is closely associated with shorter overall survival of MM patients, implying that c-Myc is a potential therapeutic target.

Main Methods

We identified a potential c-Myc inhibitor 7594-0037 by structure-based virtual screening from the ChemDiv database. CCK8 assay and flow cytometry were used to detect MM cell viability, cell cycle and apoptosis. Q-PCR and Western blot were used to measure corresponding mRNA and protein expression levels. Protein stability assay measured the stability of c-Myc.

Results

Compound 7594-0037 exhibited stronger anti-proliferative activity against MM cells, and induced MM cell cycle G2 phase arrest and apoptosis. More importantly, compound 7594-0037 overcame myeloma resistance to bortezomib and exhibited a synergistic effect with bortezomib, resulting in increased MM cell death. The mechanism consists of compound 7594-0037 facilitating c-Myc protein degradation via decreasing the c-Myc S62 phosphorylation levels mediated by PIM1 kinase. Molecular dynamics simulation with the c-Myc/7594-0037 complex showed that compound 7594-0037 bound tightly to the N-terminus of c-Myc, and blocked the binding interaction of the two termini of c-Myc, which resulted in c-Myc entering into an unstable state.

Conclusion

Overall, our study provides preliminary data for compound 7594-0037, which can be used as a novel c-Myc inhibitor and is a potential candidate therapeutic drug for multiple myeloma.

IPM712, a vanillin derivative as potential antitumor agents, displays better antitumor activity in colorectal cancers cell lines

Colorectal cancer (CRC), a major health threat in the world, ranks third in incidence and second in mortality among cancers. Chemotherapy, an important treatment for colorectal cancer, have be limited in the clinic due to the resistance and side effect. Studies have shown that PI3K-related regulatory pathways play a colossal role in colorectal cancer. Therefore, it is a good strategy to find a new drug which works by affecting the PI3K signaling pathway. In this paper, we obtained a new vanillin derivative (IPM712) by modifying the structure of IPM711 and tested its anticancer activity in vitro and toxicity in vivo. Results showed that IPM712 has a better anticancer activity than 5-Fu in HCT116 and SW480 cell lines. Furthermore, IPM712 can inhibit cell proliferation, migration and induce the apoptosis by affecting PI3K-related protein expression. Acute toxicity experiments show that IPM712 has no significant toxicity at therapeutic concentrations. Based on these results, IPM712 is a promising anticancer drug candidate for human colorectal cancer therapy.

Licoricidin improves neurological dysfunction after traumatic brain injury in mice via regulating FoxO3/Wnt/β-catenin pathway

Traumatic brain injury (TBI) is a major cause of death and disability around the world with no effective treatments currently. The present study was aimed to investigate the neuroprotective effect of licoricidin, one of the major components of licorice extract, on TBI mice and further explore the underlying mechanism. Male C57BL/6 mice were modeled by a modified weight-drop method to mimic TBI. All animals received treatment 30 min after TBI. The modified Neurological Severity Score (NSS) tests were performed at 2 h and 1-3 days after TBI. The brain edema was analyzed by dry-wet weight method. The malonaldehyde (MDA) levels and the activities of glutathione peroxidase (GSH-PX), superoxide dismutase (SOD) and catalase (CAT) were determined by Elisa. Apoptotic neurons were detected using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) immunofluorescence and the expression of apoptotic proteins were measured by western blot. Activation of the FoxO3/Wnt/β-catenin was evaluated by western blot. The results showed that treatment with licoricidin could significantly decline the NSS scores and reduce the brain edema, hence promote the recovery of neurological function in TBI mice. It also elevated the phosphorylation of p66^shc, brought down the levels of MDA, as well as antagonized the decrement in activities of GSH-PX, SOD and CAT induced by TBI. Moreover, licoricidin decreased the TUNEL positive neurons, downregulated the expression of Cyt-C, cleaved-Caspase-3, cleaved-Caspase-9 and Bax and upregulated the Bcl-2, attenuated cellular apoptosis. Licoricidin decreased the expression of FoxO3 and increased the Wnt/β-catenin in TBI mice. In conclusion, Licoricidin exerted neuroprotective effect on TBI model and the effect was possibly due to its antioxidative effect and antiapoptotic effect via regulating the FoxO3/Wnt/β-catenin pathway. Licoricidin may be a candidate drug for TBI therapy.

Discovery of novel quinazolinone derivatives as potential anti-HBV and anti-HCC agents

As a continuation of earlier works, a series of novel quinazolinone derivatives (5a-s) were synthesized and evaluated for their in vitro anti-HBV and anti-hepatocellular carcinoma cell (HCC) activities. Among them, compounds 5j and 5k exhibited most potent inhibitory effect on HBV DNA replication in both drug sensitive and resistant (lamivudine and entecavir) HBV strains. Interestingly, besides the anti-HBV effect, compound 5k could significantly inhibit the proliferation of HepG2, HUH7 and SK- cells, with IC₅₀ values of 5.44, 6.42 and 6.75 μM, respectively, indicating its potential anti-HCC activity. Notably, the in vitro anti-HCC activity of 5k were more potent than that of positive control 5-fluorouracil and sorafenib. Further studies revealed that compound 5k could induce HepG2 cells apoptosis by dose-dependently upregulating Bad and Bax expression and decreasing Bcl-2 and Bcl-xl protein level. Considering the potent anti-HBV and anti-HCC effect, compound 5k might be a promising lead to develop novel therapeutic agents towards HBV infection and HBV-induced HCC.

DKC1 enhances angiogenesis by promoting HIF-1α transcription and facilitates metastasis in colorectal cancer

BACKGROUND

Dyskeratosis congenita 1 (DKC1) is dysregulated in several cancers. However, the expression and function of DKC1 in colorectal cancer (CRC) is rarely reported.

METHODS

Tissue microarrays (TAMs) including 411 cases of CRC tissues and corresponding paracancerous tissues were used to examine the DKC1 expression. The correlations between the DKC1 expression and clinicopathological or survival characters were further analysed. The functions and molecular mechanism of DKC1 in CRC were investigated through a series of in vitro and in vivo experiments.

RESULTS

The result showed that DKC1 expression was increased in CRC tissues. Increased DKC1 expression was associated with high grade of TNM stage, additional lymph node metastasis, and poor prognosis of patients with CRC. Multivariate COX analysis indicated that DKC1 can act as an independent prognostic factor for patients with CRC. DKC1 also facilitated the CRC angiogenesis and metastasis by increasing HIF-1α and VEGF expression levels. Chromatin immunoprecipitation assay demonstrated that DKC1 facilitated HIF-1α expression by regulating HIF-1α promoter activity.

CONCLUSION

DKC1 appears to regulate CRC angiogenesis and metastasis through directly activating HIF-1α transcription. DKC1 can serve as an accurate indicator in predicting the prognosis of patients with CRC and act as a potential therapeutic target for CRC.

miR-4999-5p Predicts Colorectal Cancer Survival Outcome and Reprograms Glucose Metabolism by Targeting PRKAA2

Purpose

Colorectal cancer (CRC) is the third most common cancer, and the second leading cause of cancer death worldwide. Dysregulation of microRNAs has been shown to modulate glucose metabolic reprogramming in CRC. However, the functional role of miR-4999-5p in the CRC glucose metabolic shift has not been characterized.

Patients and Methods

The levels of miR-4999-5p and PRKAA2 were evaluated by RT-qPCR. Univariate and multivariate survival analyses were conducted to evaluate the prognostic value of miR-4999-5p. Cell proliferation was assessed using the CCK-8 and colony formation assays. Extracellular acidification rate, glucose uptake, cellular glucose-6-phosphate level, and lactate production were evaluated to assess the effects of miR-4999-5p on CRC glycolysis. Dual-luciferase reporter assay was conducted to investigate the direct interaction between miR-4999-5p and PRKAA2. Mouse xenograft models were established to assess the functions of miR-4999-5p in vivo.

Results

miR-4999-5p was highly expressed in CRC tissues and cell lines. In addition, miR-4999-5p was associated with tumor differentiation and TNM stage, and elevated expression of miR-4999-5p was an independent predictor of poorer overall survival. Furthermore, miR-4999-5p promoted cell proliferation and glycolysis in CRC. miR-4999-5p targeted PRKAA2 to exert its tumor-promoting functions, and PRKAA2 knockdown rescued decreased cell proliferation and glycolysis in miR-4999-5p-silenced CRC cells. In vivo experiments showed that miR-4999-5p promoted CRC growth.

Conclusion

miR-4999-5p facilitated cell growth and glucose metabolic reprogramming through direct targeting of PRKAA2. Our results showed that miR-4999-5p may be a novel prognostic marker and therapeutic target for CRC.

A Comprehensive Review for Phytochemical, Pharmacological, and Biosynthesis Studies on Glycyrrhiza spp

Licorice is extensively applied in food as well as herbal medicine across the world, possessing a substantial share in the global market. It has made great progress in chemical and pharmacological research in recent years. Currently, Glycyrrhiza uralensis Fisch., Glycyrrhiza inflata Bat., and Glycyrrhiza glabra L. were officially used as Gan-Cao according to the Chinese Pharmacopoeia. Accumulating evidence demonstrated three varieties of licorice have their own special compounds except for two quality markers set by Pharmacopoeia, providing great possibility for better understanding their characteristics, evaluating quality of each species and studying biosynthesis mechanisms of species-specific compounds. As a special "guide drug" in clinic, licorice plays an important role in Chinese herbal formulas. The interaction between licorice with other ingredients and their metabolism in vivo should also be taken into consideration. In addition, draft genome annotation, and success of the final step of glycyrrhizin biosynthesis have paved the way for biosynthesis of other active constituents in licorice, a promising beginning of solving source shortage. Accordingly, we comprehensively explored the nearly 400 chemical compounds found in the three varieties of licorice so far, systematically excavated various pharmacological activities, including metabolism via CYP450 system in vivo, and introduced the complete biosynthesis pathway of glycyrrhizin in licorice. The review will facilitate the further research toward this herbal medicine.

Structural Design, Synthesis, and Preliminary Biological Evaluation of Novel Dihomooxacalix[4]arene-Based Anti-tumor Agents

Calixarene and its derivatives have extensively served as promising anti-tumor agents. Previously, we have synthesized a series of calix[n]arene polyhydroxyamine derivatives (n = 4, 6, 8) and found that 5,11,17,23-tetra-tert-butyl-25,27-bis [N-(2-hydroxyethyl)aminocarbonylmethoxyl] calix[4]arene (CLX-4) displayed significant effect toward SKOV3, A549, SW1990, HeLa, Raji, and MDA-MB-231 cancer cells. In the present work, we find a replacement of calix[4]arene bone and synthesized 19 novel structurally related dihomooxacalix[4]arene amide derivatives 4A-4S to optimize its efficacy. Their abilities to induce cytotoxicity in human lung carcinoma (A549) cells, breast cancer (MCF-7) cells, cervical cancer (HeLa) cells, hepatocellular carcinoma (HepG2) cells, as well as human umbilical vein endothelial (HUVEC) cells are evaluated in vitro. Encouraging results show that the majority of dihomooxacalix[4]arene amide derivatives are effective at inhibiting A549 cell proliferation with the corresponding IC₅₀ ranging from 0.6 to 20.1 μM. In particular, compounds 4A, 4D, and 4L explore markedly increased potency (IC₅₀ value is 2.0 ± 0.5 μM, 0.7 ± 0.1 μM, and 1.7 ± 0.4 μM) over the cytotoxicity profiles of control CLX-4, whose IC₅₀ value is 2.8 ± 0.3 μM. More interestingly, 4A also demonstrates the perfect cytotoxic effect against MCF-7, HeLa, and HepG2 cells with IC₅₀ values of 1.0 ± 0.1 μM, 0.8 ± 0.2 μM, and 2.7 ± 0.4 μM. In addition, the results proved that our synthesized 4A has much lower toxicity (41%) to normal cells at a concentration of 10 μM than that of 4D (90%). To reveal the mechanisms, the key indicators including the cell cycle and apoptosis are observed by the flow cytometry analysis in MCF-7 cells. The results demonstrate that both 4A and 4D can induce the MCF-7 cell cycle arrest in G0/G1 phase and cell apoptosis. Therefore, our finding proves that the dihomooxacalix[4]arene amide derivatives are convenient platforms for potential supramolecular anticancer agents.

Knockdown of KLK12 inhibits viability and induces apoptosis in human colorectal cancer HT-29 cell line

Kallikrein-related peptidase 12 (KLK12) is overexpressed in cancer tissues including gastric, breast and prostate cancer. However, the role of KLK12 in colorectal cancer is not fully understood. In the present study, the level of KLK12 was determined by performing reverse transcription-polymerase chain reaction (RT-qPCR) in colorectal cancer tissues and cell lines. Lipofectamine^® 2000 was used to transfect HT-29 cells to overexpress and knockdown KLK12. Cell viability, migration, invasion and apoptosis were detected by MTT, wound healing, Transwell and flow cytometry assays, respectively. The mRNA and protein expression levels of EMT-associated proteins, apoptosis-associated proteins, phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK) and phosphorylated mammalian target of rapamycin (p-mTOR) were determined by RT-qPCR and western blot analysis. It was identified that the KLK12 mRNA levels were increased significantly in colorectal cancer tissues and cell lines. KLK12 small interfering RNA inhibited cell viability, migration and invasion. Furthermore, epithelial-mesenchymal transition (EMT)-associated proteins were altered by siKLK12. Cell apoptosis was induced by KLK12 downregulation, which was demonstrated by the changes in apoptosis-associated proteins; however, KLK12 overexpression produced the opposite effect. SiKLK12 enhanced the expression of p-AMPK and suppressed the expression of p-mTOR, while KLK12 overexpression had the opposite effect. Promotion of KLK12 overexpression-induced cell viability was reversed by 5-aminoimidazole-4-carboxamide ribonucleotide, an activator of the AMPK signaling pathway, and rapamycin, a specific inhibitor of the mTOR signaling pathway. Taken together, the results of the present study indicated that KLK12 was overexpressed in colorectal cancer and may regulate cell behavior, potentially via the AMPK and mTOR pathways.

Glycyrrhiza glabra-Enhanced Extract and Adriamycin Antiproliferative Effect on PC-3 Prostate Cancer Cells

Prostate cancer is the second most commonly diagnosed cancer in men worldwide, which is almost incurable, once it progresses into the metastatic stage. Adriamycin (ADR) is a known chemotherapeutic agent that causes severe side effects. In recent years, studies in natural plant products have revealed their anticancer activities. In particular, Glycyrrhiza glabra enhanced extract (GGE), commonly known as licorice, has been reported to exert antiproliferative properties against cancer cells. In this study, the cytotoxic potential of GGE was assessed in PC-3 cells, when it is administrated alone or in combination with Adriamycin. PC-3 cells were treated with GGE and/or ADR, and the inhibition of cell proliferation was evaluated by the MTT assay. Cell cycle alterations and apoptosis rate were measured through flow cytometry. Expression levels of autophagy-related genes were evaluated with specific ELISA kits, Western blotting, and real-time PCR, while NMR spectrometry was used to identify the implication of specific metabolites. Our results demonstrated that GGE alone or in co-treatment with ADR shows antiproliferative properties against PC-3 cells, which are mediated by both apoptosis and autophagy mechanisms.

Structure-Based Discovery of a Selective KDM5A Inhibitor that Exhibits Anti-Cancer Activity via Inducing Cell Cycle Arrest and Senescence in Breast Cancer Cell Lines

Breast cancer is the one of the most frequent causes of female cancer mortality. KDM5A, a histone demethylase, can increase the proliferation, metastasis, and drug resistance of cancers, including breast cancer, and is thus an important therapeutic target. In the present work, we performed hierarchical virtual screening towards the KDM5A catalytic pocket from a chemical library containing 90,000 compounds. Using multiple biochemical methods, the cyclopenta[c]chromen derivative 1 was identified as the top candidate for KDM5A demethylase inhibitory activity. Compared with the well-known KDM5 inhibitor CPI-455 (18), 1 exhibited higher potency against KDM5A and much higher selectivity for KDM5A over both KDM4A and other KDM5 family members (KDM5B and KDM5C). Additionally, compound 1 repressed the proliferation of various KDM5A-overexpressing breast cancer cell lines. Mechanistically, 1 promoted accumulation of p16 and p27 by blocking KDM5A-mediated H3K4me3 demethylation, leading to cell cycle arrest and senescence. To date, compound 1 is the first cyclopenta[c]chromen-based KDM5A inhibitor reported, and may serve as a novel motif for developing more selective and efficacious pharmacological molecules targeting KDM5A. In addition, our research provides a possible anti-cancer mechanism of KDM5A inhibitors and highlights the feasibility and significance of KDM5A as a therapeutic target for KDM5A-overexpressing breast cancer.

Inhibition effect of glycyrrhiza polysaccharide (GCP) on tumor growth through regulation of the gut microbiota composition

Glycyrrhiza Uralensis Polysaccharide (GCP), as a macromolecular polysaccharide extracted from the Traditional Chinese Medicine (TCM) - Licorice has been proved to inhibit tumor growth in vitro and in vivo; however, the specific anti-tumor mechanism of GCP needs to be further investigated. In this study, we explore the anti-tumor mechanism of GCP from the angle of gut microbiota. Colon carcinoma cells (CT-26) were used to set up a tumor-bearing mouse model. After 14 days of GCP treatment, the weights of tumors were significantly reduced. In addition, HE staining of tissue sections reflected that GCP could effectively inhibit tumor metastasis. 16SrRNA high-throughput sequencing of fecal samples showed a significant change between the model group and GCP group in the composition of gut microbiota. Subsequently, gut microbiota depletion and fecal transplantation experiments further confirmed the relationship between the anti-tumor effects of GCP and gut microbiota. Following depletion of gut microbiota, GCP cannot inhibit tumor growth. Fecal transplantation experiments found that transplanting the feces of GCP-treated mice, to a certain extent, could inhibit tumor growth and metastasis. These results indicate that Glycyrrhiza Polysaccharides exert anti-tumor effects by affecting gut microbiota composition.

Total Flavonoids from Radix Glycyrrhiza Exert Anti-Inflammatory and Antitumorigenic Effects by Inactivating iNOS Signaling Pathways

Inducible nitric oxide synthase (iNOS) plays an important role in inflammation, which has also been considered as a major driver of breast cancer disease progression. Radix Glycyrrhiza (RG) has been broadly used for its anti-inflammatory and antitumorigenic effects. However, the mechanisms of regulation of iNOS in inflammation and cancer have not been fully explored. Total flavonoids isolated from RG (TFRG) exhibited anti-inflammatory activity through the regulation of ERK/NF-κB/miR-155 signaling and suppression of iNOS expression in LPS/IFN-γ stimulated RAW264.7 macrophages without cytotoxicity. TFRG also markedly reduced tumor mass of breast cancer cell MDA-MB-231 xenografts with suppression of iNOS expression, formation of 3-nitrotyrosine (3-NT), and inactivation of protumorigenic JAK2/STAT3 signaling pathway. These results suggested that TFRG limited the development of breast cancer and inflammation due to its property of iNOS inhibition.

Licoricidin enhances gemcitabine-induced cytotoxicity in osteosarcoma cells by suppressing the Akt and NF-κB signal pathways

Osteosarcoma (OS) is the most common bone malignancy in children and adolescents. Combined treatments of anti-cancer drugs can remarkably improve chemotherapeutic outcomes. Gemcitabine and licoricidin both have potential anti-tumor activity in several cancers. However, the combined therapeutic efficiency of gemcitabine and licoricidin for OS has not been explored. Here, we found that licoricidin or gemcitabine inhibited OS cell viability in a dose-dependent manner. Cotreatment with licoricidin and gemcitabine enhanced gemcitabine-induced cytotoxicity in OS cells. Licoricidin suppressed activation of the Akt and nuclear factor-kappa B (NF-κB) pathways. Gemcitabine had no effect on Akt signal, but facilitated the activation of NF-κB signal in OS cells. Moreover, combined treatment of licoricidin and gemcitabine markedly curbed the activation of Akt and NF-κB pathways in OS cells. Inhibition of the Akt and NF-κB pathways enhanced gemcitabine-induced cytotoxicity in OS cells. In vivo assay further manifested that licoricidin enhanced gemcitabine-induced cytotoxicity in tumor xenograft models of OS via inactivation of the Akt and NF-κB pathways. In conclusion, licoricidin enhanced gemcitabine-induced cytotoxicity in OS cells by inactivation of the Akt and NF-κB pathways in vitro and in vivo.

Herbal medicine for hand-foot syndrome induced by fluoropyrimidines: A systematic review and meta-analysis

The aims of this study were to evaluate the efficacy of herbal medicine for the prevention and management of hand-foot syndrome (HFS) induced by fluoropyrimidines and to identify herbs associated with HFS alleviation for further research. The PubMed, Cochrane, Springer, China National Knowledge Infrastructure, and Wanfang databases were searched up to May 2017 for randomized controlled trials (RCTs) that evaluated herbal medicine for relieving HFS in patients undergoing fluoropyrimidine-based chemotherapy. Study evaluation and synthesis methods were in accordance with the Cochrane Handbook, and data were analyzed using RevMan 5.3. In total, 35 RCTs (2,668 participants) were included. Meta-analysis showed that the addition of herbal medicine significantly reduced the incidences of all-grade and high-grade HFS. The total effective rate and complete remission rate of HFS patients increased significantly with herbal medicine arm. Further sensitivity analysis identified Paeoniae Radix Alba, Carthami Flos, Cinnamomi Ramulus, and Glycyrrhizae Radix et Rhizoma as being consistently associated with significant reductions in HFS incidence without important heterogeneity. However, the lack of blinding in most studies may have led to overestimation of these effects. More high-quality RCTs and experimental research are needed to confirm and investigate the efficacy of the herbs identified in this study.

Perspective on Biotransformation and De Novo Biosynthesis of Licorice Constituents

Licorice, an important herbal medicine, is derived from the dried roots and rhizomes of Glycyrrhiza genus plants. It has been widely used in food, pharmaceutical, tobacco, and cosmetics industries with high economic value. However, overexploitation of licorice resources has severely destroyed the local ecology. Therefore, producing bioactive compounds of licorice through the biotransformation and bioengineering methods is a hot spot in recent years. In this perspective, we comprehensively summarize the biotransformation of licorice constituents into high-value-added derivatives by biocatalysts. Furthermore, successful cases and the strategies for de novo biosynthesizing compounds of licorice in microbes have been summarized. This paper will provide new insights for the further research of licorice.

Arginine methyltransferase inhibitor 1 inhibits gastric cancer by downregulating eIF4E and targeting PRMT5

Arginine methylation is carried out by protein arginine methyltransferase (PRMTs) family. Arginine methyltransferase inhibitor 1 (AMI-1) is mainly used to inhibit type I PRMT activity in vitro. However, the effects of AMI-1 on type II PRMT5 activity and gastric cancer (GC) remain unclear. In this study, we provided the first evidence that AMI-1 significantly inhibited GC cell proliferation and migration while induced GC cell apoptosis, and reduced the expression of PRMT5, eukaryotic translation initiation factor 4E (eIF4E), symmetric dimethylation of histone 3 (H3R8me2s) and histone 4 (H4R3me2s). In addition, AMI-1 inhibited tumor growth, downregulated eIF4E, H4R3me2s and H3R8me2s expression in mice xenografts model of GC. Collectively, our results suggest that AMI-1 inhibits GC by downregulating eIF4E and targeting type II PRMT5.