Licochalcone A Suppresses Specificity Protein 1 as a Novel Target in Human Breast Cancer Cells

Licochalcone A: a review of its pharmacology activities and molecular mechanisms

Licorice, derived from the root of Glycyrrhiza uralensis Fisch, is a key Traditional Chinese Medicine known for its detoxifying, spleen-nourishing, and qi-replenishing properties. Licochalcone A (Lico A), a significant component of licorice, has garnered interest due to its molecular versatility and receptor-binding affinity. This review explores the specific roles of Lico A in various diseases, providing new insights into its characteristics and guiding the rational use of licorice. Comprehensive literature searches using terms such as "licorice application" and "pharmacological activity of Lico A" were conducted across databases including CNKI, PubMed, and Google Scholar to gather relevant studies on Lico A's pharmacological activities and mechanisms. Lico A, a representative chalcone in licorice, targets specific mechanisms in anti-cancer and anti-inflammatory activities. It also plays a role in post-transcriptional regulation. This review delineates the similarities and differences in the anti-cancer and anti-inflammatory mechanisms of Lico A, concluding that its effects on non-coding RNA through post-transcriptional mechanisms deserve further exploration.

Licochalcone A induces mitochondria-dependent apoptosis and interacts with venetoclax in acute myeloid leukemia

The management of patients with acute myeloid leukemia (AML) remains a challenge because of the complexity and heterogeneity of this malignancy. Despite the recent approval of several novel targeted drugs, resistance seems inevitable, and clinical outcomes are still suboptimal. Increasing evidence supports the use of natural plants as an important source of anti-leukemic therapeutics. Licochalcone A (LCA) is an active flavonoid isolated from the roots of licorice, Glycyrrhiza uralensis Fisch., possessing extensive anti-tumor activities. However, its effects on AML and the underlying mechanisms remain unknown. Here, we showed that LCA decreased the viability of established human AML cell lines in a dose- and time-dependent manner. LCA significantly induced mitochondrial apoptotic cell death, accompanied by the downregulation of MCL-1, upregulation of BIM, truncation of BID, and cleavage of PARP. A prominent decline in the phosphorylation of multiple critical molecules, including AKT, glycogen synthase kinase-3β (GSK3β), ERK, and P38 was observed upon LCA treatment, indicating PI3K and MAPK signals were suppressed. Both transcription and translation of c-Myc were also inhibited by LCA. In addition, LCA enhanced the cytotoxicity of the BCL-2 inhibitor venetoclax. Furthermore, the anti-survival and pro-apoptotic effects were confirmed in primary blasts from 10 patients with de novo AML. Thus, our results expand the applications of LCA, which can be regarded as a valuable agent in treating AML.

Licochalcone H Targets EGFR and AKT to Suppress the Growth of Oxaliplatin -Sensitive and -Resistant Colorectal Cancer Cells

Treatment of colorectal cancer (CRC) has always been challenged by the development of resistance. We investigated the antiproliferative activity of licochalcone H (LCH), a regioisomer of licochalcone C derived from the root of Glycyrrhiza inflata, in oxaliplatin (Ox)-sensitive and -resistant CRC cells. LCH significantly inhibited cell viability and colony growth in both Ox-sensitive and Ox-resistant CRC cells. We found that LCH decreased epidermal growth factor receptor (EGFR) and AKT kinase activities and related activating signaling proteins including pEGFR and pAKT. A computational docking model indicated that LCH may interact with EGFR, AKT1, and AKT2 at the ATP-binding sites. LCH induced ROS generation and increased the expression of the ER stress markers. LCH treatment of CRC cells induced depolarization of MMP. Multi-caspase activity was induced by LCH treatment and confirmed by Z-VAD-FMK treatment. LCH increased the number of sub-G1 cells and arrested the cell cycle at the G1 phase. Taken together LCH inhibits the growth of Ox-sensitive and Ox-resistant CRC cells by targeting EGFR and AKT, and inducing ROS generation and ER stress-mediated apoptosis. Therefore, LCH could be a potential therapeutic agent for improving not only Ox-sensitive but also Ox-resistant CRC treatment.

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.

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.

Licochalcone A Exerts Anti-Cancer Activity by Inhibiting STAT3 in SKOV3 Human Ovarian Cancer Cells

Licochalcone A (LicA), a major active component of licorice, has been reported to exhibit various pharmacological actions. The purpose of this study was to investigate the anticancer activity of LicA and detail its molecular mechanisms against ovarian cancer. SKOV3 human ovarian cancer cells were used in this study. Cell viability was measured using a cell counting kit-8 assay. The percentages of apoptotic cells and cell cycle arrest were determined by flow cytometry and Muse flow cytometry. The expression levels of proteins regulating cell apoptosis, cell cycle, and the signal transducer and activator of transcription 3 (STAT3) signaling pathways were examined using Western blotting analysis. The results indicated that LicA treatment inhibited the cell viability of SKOV3 cells and induced G2/M phase arrest. Furthermore, LicA induced an increase in ROS levels, a reduction in mitochondrial membrane potential, and apoptosis accompanied by an increase in cleaved caspases and cytoplasmic cytochrome c. Additionally, LicA caused a dramatic decrease in STAT3 protein levels, but not mRNA levels, in SKOV3 cells. Treatment with LicA also reduced phosphorylation of the mammalian target of rapamycin and eukaryotic translation initiation factor 4E-binding protein in SKOV3 cells. The anti-cancer effects of LicA on SKOV3 cells might be mediated by reduced STAT3 translation and activation.

Anticancer effects of licochalcones: A review of the mechanisms

Cancer is a disease with a high fatality rate representing a serious threat to human health. Researchers have tried to identify effective anticancer drugs. Licorice is a widely used traditional Chinese medicine with various pharmacological properties, and licorice-derived flavonoids include licochalcones like licochalcone A, licochalcone B, licochalcone C, licochalcone D, licochalcone E, and licochalcone H. By regulating the expression in multiple signaling pathways such as the EGFR/ERK, PI3K/Akt/mTOR, p38/JNK, JAK2/STAT3, MEK/ERK, Wnt/β-catenin, and MKK4/JNK pathways, and their downstream proteins, licochalcones can activate the mitochondrial apoptosis pathway and death receptor pathway, promote autophagy-related protein expression, inhibit the expression of cell cycle proteins and angiogenesis factors, regulate autophagy and apoptosis, and inhibit the proliferation, migration, and invasion of cancer cells. Among the licochalcones, the largest number of studies examined licochalcone A, far more than other licochalcones. Licochalcone A not only has prominent anticancer effects but also can be used to inhibit the efflux of antineoplastic drugs from cancer cells. Moreover, derivatives of licochalcone A exhibit strong antitumor effects. Currently, most results of the anticancer effects of licochalcones are derived from cell experiments. Thus, more clinical studies are needed to confirm the antineoplastic effects of licochalcones.

Role of Licochalcone A in Potential Pharmacological Therapy: A Review

Licochalcone A (LA), a useful and valuable flavonoid, is isolated from Glycyrrhiza uralensis Fisch. ex DC. and widely used clinically in traditional Chinese medicine. We systematically updated the latest information on the pharmacology of LA over the past decade from several authoritative internet databases, including Web of Science, Elsevier, Europe PMC, Wiley Online Library, and PubMed. A combination of keywords containing “Licochalcone A,” “Flavonoid,” and “Pharmacological Therapy” was used to help ensure a comprehensive review. Collected information demonstrates a wide range of pharmacological properties for LA, including anticancer, anti-inflammatory, antioxidant, antibacterial, anti-parasitic, bone protection, blood glucose and lipid regulation, neuroprotection, and skin protection. LA activity is mediated through several signaling pathways, such as PI3K/Akt/mTOR, P53, NF-κB, and P38. Caspase-3 apoptosis, MAPK inflammatory, and Nrf2 oxidative stress signaling pathways are also involved with multiple therapeutic targets, such as TNF-α, VEGF, Fas, FasL, PI3K, AKT, and caspases. Recent studies mainly focus on the anticancer properties of LA, which suggests that the pharmacology of other aspects of LA will need additional study. At the end of this review, current challenges and future research directions on LA are discussed. This review is divided into three parts based on the pharmacological effects of LA for the convenience of readers. We anticipate that this review will inspire further research.

Effect of Licochalcone-A Combined with Rab23 Gene on Proliferation of Glioma U251 Cells

This research aimed to explore the effect of Licochalcone-A (LCA) combined with Rab23 gene on the proliferation, migration, and invasion of glioma U251 cells through the Wnt/β-catenin signaling pathway. The glioma U251 cell line was taken as the research object, and the Rab23 overexpression plasmid was constructed. According to the treatment method, U251 cells were rolled into blank control group (BC), Rab23 overexpression plasmid transfection group (Rab23), 25 μmol·L⁻¹ LCA treatment group (LCA), and Rab23 overexpression plasmid transfection combined with 25 μmol·L⁻¹ LCA treatment group (Rab23 + LCA). Subsequently, the ability of cell proliferation, migration, and invasion of each group was detected by methyl thiazolyl tetrazolium (MTT) assay, scratch healing test, and Transwell cell invasion test, respectively. Western blot was implemented to detect the expression differences of cell proliferation antigen Ki-67, apoptosis-related proteins Bcl-2 and Bax, and Wnt/β-catenin pathway-related proteins β-catenin, glycogen synthase kinase-3 (GSK3β), Axin2, and c-myc. The results showed the successful construction of Rab23 overexpression and stable transfection U251 cell line. After grouping and treatments, the cell proliferation, migration, and invasion ability of the Rab23 group, LCA group, and Rab23 + LCA group was substantially reduced relative to BC group (P < 0.05). In addition, the cell proliferation, migration, and invasion ability of Rab23 + LCA group decreased relatively more significantly. The expression levels of Ki-67, Bcl-2, β-catenin, and c-myc in the Rab23, LCA, and Rab23 + LCA groups were greatly lower versus those of BC group. Moreover, the protein expression levels of Bax, GSK3β, and Axin2 were considerably increased (P < 0.05), while the expression of protein in Rab23 + LCA group increased notably. These findings indicate that LCA combined with Rab23 gene can inhibit the proliferation, migration, and invasion of glioma U251 cells through the Wnt/β-catenin signaling and can promote cell apoptosis.

Pharmacological Effects and Underlying Mechanisms of Licorice-Derived Flavonoids

Glycyrrhizae Radix et Rhizoma is the most frequently prescribed natural medicine in China and has been used for more than 2,000 years. The flavonoids of licorice have garnered considerable attention in recent decades due to their structural diversity and myriad pharmacological effects, especially as novel therapeutic agents against inflammation and cancer. Although many articles have been published to summarize different pharmacological activities of licorice in recent years, the systematic summary for flavonoid components is not comprehensive. Therefore, in this review, we summarized the pharmacological and mechanistic data from recent researches on licorice flavonoids and their bioactive components.

Cytotoxic and Antimigration Activity of Etlingera alba (A.D.) Poulsen Rhizome

Etlingera alba is one of the Etlingera plants that might have anticancer activity. This study aims to investigate the cytotoxic and antimetastatic activity of E. alba rhizome fractions and migration cell assay against MDA-MB-231 cell lines, which are used for triple-negative breast cancer (TNBC) treatment assay. The cytotoxic activity was assayed using CCK-8 assay, while the antimetastatic was assayed using migration cell assay for the fractions A–F. They were followed by LCMS/MS profiling to determine the chemical contents in the most active fraction. According to results obtained, fraction B was the most active fraction for cytotoxic activity with an IC₅₀ value of 65.43 μg/mL, while fraction E was the most active fraction for antimetastasis activity against migration rate doses of 50, 100, and 200 ppm which were 6.80, 3.66, and 3.00%, respectively. Several compounds in fraction B, such as rengyolone, licochalcone A, sugiol, and spinasterol, might have been known to have activity against cancer cells, as well as aschantin and lirioresinol B dimethyl ether from fraction E. In conclusion, the chemical components from E. alba rhizome fractions provided potency for discovering new agents for cancer treatment, specifically for TNBC.

Licochalcone H Induces Cell Cycle Arrest and Apoptosis in Human Skin Cancer Cells by Modulating JAK2/STAT3 Signaling

Licochalcone H (LCH) is a phenolic compound synthetically derived from licochalcone C (LCC) that exerts anticancer activity. In this study, we investigated the anticancer activity of LCH in human skin cancer A375 and A431 cells. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) cell viability assay was used to evaluate the antiproliferative activity of LCH. Cell cycle distribution and the induction of apoptosis were analyzed by flow cytometry. Western blotting assays were performed to detect the levels of proteins involved in cell cycle progression, apoptosis, and the JAK2/STAT3 signaling pathway. LCH inhibited the growth of cells in dose- and time-dependent manners. The annexin V/propidium iodide double staining assay revealed that LCH induced apoptosis, and the LCH-induced apoptosis was accompanied by cell cycle arrest in the G1 phase. Western blot analysis showed that the phosphorylation of JAK2 and STAT3 was decreased by treatment with LCH. The inhibition of the JAK2/STAT3 signaling pathway by pharmacological inhibitors against JAK2/STAT3 (cryptotanshinone (CTS) and S3I-201) simulated the antiproliferative effect of LCH suggesting that LCH induced apoptosis by modulating JAK2/STAT3 signaling.

Chalcones against the hallmarks of cancer: a mini-review

Chalcones (1,3-diphenylpropen-1-ones) are a class of flavonoids that have been shown a broad spectrum of biological activities with therapeutic potential. Naturally occurring chalcones or synthetic chalcone derivatives have been extensively investigated as anticancer compounds. Cancer is still among the leading causes of death globally, although cancer treatments have improved over the past decades. Most of chemotherapeutic drugs target proliferating tumor cells; however, the cancer cells capabilities are also associated to tumor surround microenvironment. Thereby, the search of new compounds with a broad antitumor activity is still a great challenge. The cytotoxicity mechanisms of chalcones are beyond apoptosis induction in tumor cells, which make them promising compound for cancer therapy. In this mini-review we summarized recent studies that describe the anticancer potential of chalcones related to some of hallmarks of cancer. We shed a light on sustaining proliferative signaling, tumor-promoting inflammation, activating invasion and metastasis, inducing angiogenesis and resisting cell death.

Cell type-specific expression of estrogen and progesterone receptors in the human vaginal mucosa

Female sex hormones affect the immune response in the lower female genital tract. To understand their mechanisms of action, it is essential to define cell types expressing estrogen receptor (ER) and/or progesterone receptor (PR) in the human vaginal mucosa (VM). Here, we report that none of the dendritic cell (DC) subsets in the human VM expressed ERα or PR in situ. However, they were capable of expressing ERα, but not PR, after in vitro culture of the whole VM tissues. Similarly, ERα and/or PR expression by T cells in the VM tissues was also inducible rather than constitutive. In contrast, ERα and/or PR were constitutively expressed in HLA-DR^- non-immune cell types (vimentin⁺, desmin⁺, or CD10⁺). These new findings will help us understand the mechanisms of action of female sex hormones in the modulation of immune response in the human VM and lower female genital tract.

Chalcone Derivatives and their Activities against Drug-resistant Cancers: An Overview

Drug resistance, including multidrug resistance resulting from different defensive mechanisms in cancer cells, is the leading cause of the failure of the cancer therapy, posing an urgent need to develop more effective anticancer agents. Chalcones, widely distributed in nature, could act on diverse enzymes and receptors in cancer cells. Accordingly, chalcone derivatives possess potent activity against various cancers, including drug-resistant, even multidrug-resistant cancer. This review outlines the recent development of chalcone derivatives with potential activity against drug-resistant cancers covering articles published between 2010 and 2020 so as to facilitate further rational design of more effective candidates.

Licochalcone A is a Natural Selective Inhibitor of Arginine Methyltransferase 6

Arginine methylation is a post-translational modification that is implicated in multiple biological functions including transcriptional regulation. The expression of protein arginine methyltransferases (PRMT) has been shown to be upregulated in various cancers. PRMTs have emerged as attractive targets for the development of new cancer therapies. Here, we describe the identification of a natural compound, licochalcone A, as a novel, reversible and selective inhibitor of PRMT6. Since expression of PRMT6 is upregulated in human breast cancers and is associated with oncogenesis, we used the human breast cancer cell line system to study the effect of licochalcone A treatment on PRMT6 activity, cell viability, cell cycle, and apoptosis. We demonstrated that licochalcone A is a non-S-adenosyl L-methionine (SAM) binding site competitive inhibitor of PRMT6. In MCF-7 cells, it inhibited PRMT6-dependent methylation of histone H3 at arginine 2 (H3R2), which resulted in a significant repression of estrogen receptor activity. Licochalcone A exhibited cytotoxicity towards human MCF-7 breast cancer cells, but not MCF-10A human breast epithelial cells, by upregulating p53 expression and blocking cell cycle progression at G2/M, followed by apoptosis. Thus, licochalcone A has potential for further development as a therapeutic agent against breast cancer.

Natural and herbal compounds targeting breast cancer, a review based on cancer stem cells

Cancer stem cells (CSCs) are known as the major reason for therapy resistance. Recently, natural herbal compounds are suggested to have a significant role in inhibiting the breast cancer stem cells (BCSCs). The aim of this study was to explore the effective natural herbal compounds against BCSCs.This review article was designed based on the BCSCs, mechanisms of therapy resistance and natural herbal compounds effective to inhibit their activity. Therefore, Science direct, PubMed and Scopus databases were explored and related original articles were investigated from 2010 to 2019. BCSCs use different mechanisms including special membrane transporters, anti-apoptotic, pro-survival, and self-renewal- related signaling pathways. Natural herbal compounds could disturb these mechanisms, therefore may inhibit or eradicate the BCSCs. Studies show that a broad range of plants, either as a food or medicine, contain anti-cancer agents that phenolic components and their different derivatives share a large quantity. Natural herbal compounds play a pivotal role in the eradication of BCSCs, through the inhibition of biological activities and induction of apoptosis. Although it is necessary to conduct more clinical investigation.

Licochalcone A Selectively Resensitizes ABCG2-Overexpressing Multidrug-Resistant Cancer Cells to Chemotherapeutic Drugs

The overexpression of the ATP-binding cassette (ABC) transporter ABCG2 has been linked to clinical multidrug resistance in solid tumors and blood cancers, which remains a significant obstacle to successful cancer chemotherapy. For years, the potential modulatory effect of bioactive compounds derived from natural sources on ABCG2-mediated multidrug resistance has been investigated, as they are inherently well tolerated and offer a broad range of chemical scaffolds. Licochalcone A (LCA), a natural chalcone isolated from the root of Glycyrrhiza inflata, is known to possess a broad spectrum of biological and pharmacological activities, including pro-apoptotic and antiproliferative effects in various cancer cell lines. In this study, the chemosensitization effect of LCA was examined in ABCG2-overexpressing multidrug-resistant cancer cells. Experimental data demonstrated that LCA inhibits the drug transport function of ABCG2 and reverses ABCG2-mediated multidrug resistance in human multidrug-resistant cancer cell lines in a concentration-dependent manner. Results of LCA-stimulated ABCG2 ATPase activity and the in silico docking analysis of LCA to the inward-open conformation of human ABCG2 suggest that LCA binds ABCG2 in the transmembrane substrate-binding pocket. This study provides evidence that LCA should be further evaluated as a modulator of ABCG2 in drug combination therapy trials against ABCG2-expressing drug-resistant tumors.

Inhibitory Effect of Hydroxysafflor Yellow B on the Proliferation of Human Breast Cancer MCF-7 Cells

BACKGROUND

A recent patent has been issued for hydroxysafflor yellow A (HSYA) as a drug to prevent blood circulation disorders. Hydroxysafflor yellow B (HSYB), an isomer of HSYA with antioxidative effects, has been isolated from the florets of Carthamus tinctorius. The effects of HSYB on the proliferation of cancer cells and its mechanism of action have not been investigated.

OBJECTIVE

The aims of this study were to investigate the anti-cancer effects and the molecular mechanism of HSYB for breast cancer MCF-7 cells.

METHODS

MTT assays and colony formation assays were used to assess the survival and proliferation of MCF-7 cells, respectively. Hoechst 33258 and flow cytometry were used to measure cell apoptosis and flow cytometry to determine effects on the cell cycle. Western blots were used to measure protein levels.

RESULTS

Treatment with HSYB reduced survival and proliferation of human breast cancer MCF-7 cells in a dose-dependent manner. Furthermore, HSYB arrested the MCF-7 cell cycle at the S phase and downregulated cyclin D1, cyclin E, and CDK2. Compared with a control group, HSYB suppressed the protein levels of p-PI3K, PI3K, AKT, and p-AKT in MCF-7 cells. In addition, HSYB decreased the levels of Bcl- 2, increased the levels of Bax, cleaved caspase-3 and caspase-9, and subsequently induced MCF-7 cell apoptosis.

CONCLUSION

These data demonstrate that HSYB arrests the MCF-7 cell cycle at the S phase and induces cell apoptosis. Patent US20170246228 indicates that HSYB can be potentially used for the prevention and treatment of human breast cancer.

Anti-Proliferative and Pro-Apoptotic Effects of Licochalcone A through ROS-Mediated Cell Cycle Arrest and Apoptosis in Human Bladder Cancer Cells

Licochalcone A (LCA) is a chalcone that is predominantly found in the root of Glycyrrhiza species, which is widely used as an herbal medicine. Although previous studies have reported that LCA has a wide range of pharmacological effects, evidence for the underlying molecular mechanism of its anti-cancer efficacy is still lacking. In this study, we investigated the anti-proliferative effect of LCA on human bladder cancer cells, and found that LCA induced cell cycle arrest at G2/M phase and apoptotic cell death. Our data showed that LCA inhibited the expression of cyclin A, cyclin B1, and Wee1, but increased the expression of cyclin-dependent kinase (Cdk) inhibitor p21WAF1/CIP1, and increased p21 was bound to Cdc2 and Cdk2. LCA activated caspase-8 and -9, which are involved in the initiation of extrinsic and intrinsic apoptosis pathways, respectively, and also increased caspase-3 activity, a typical effect caspase, subsequently leading to poly (ADP-ribose) polymerase cleavage. Additionally, LCA increased the Bax/Bcl-2 ratio, and reduced the integrity of mitochondria, which contributed to the discharge of cytochrome c from the mitochondria to the cytoplasm. Moreover, LCA enhanced the intracellular levels of reactive oxygen species (ROS); however, the interruption of ROS generation using ROS scavenger led to escape from LCA-mediated G2/M arrest and apoptosis. Collectively, the present data indicate that LCA can inhibit the proliferation of human bladder cancer cells by inducing ROS-dependent G2/M phase arrest and apoptosis.

Biological Effects of Licochalcones

Medicinal plants and their natural bioactive molecules, are evaluated as the foundation for health preservation and care of humanity. The licorice root, known as "Radix Glycyrrhizae", is a perennial plant that comes from Mediterranean countries, central to southern Russia, Asia, Turkey, Iraq and Iran. The licorice root has been used in traditional Chinese medicines for centuries and has been defined as "the progenitor of herbs". The name 'Licorice' is derived from the ancient Greek word Glukurrhiza, meaning 'sweet root'. It consists of approximately 30 species, however, the most common ones consist of Glycyrrhiza glabra L., Glycyrrhiza uralensis Fisch and Glycyrrhiza Inflata. In addition, the licorice root contains chalcones, which are a part of an important class of natural products and are precursors of flavonoids. Chemically, chalcones are composed of two aromatic rings associated with α, β-unsaturated α-carbon ketone, representing the prima nucleus of the structure. They have been classified, according to chemical structures, in Licochalcone A, B, C, D, E, F and G. This review aims to highlight all the in vitro and in vivo studies that have been conducted on the licochalcones, extracted from Glycyrrhiza species. The main effects are as follows: anti-inflammatory, antioxidant, anticancer, antimicrobial, antiviral, antiallergic, antidiabetic, hepatotoxic and osteogenic. It is important to implement the introduction of biologically active natural molecules from the bench (research) to the bedside (clinical practice). However, in the future, it is required to conduct additional studies to validate these biological effects.

Network analysis and mechanisms of action of Chinese herb-related natural compounds in lung cancer cells

BACKGROUND

Chinese herbal medicines (CHMs) are a resource of natural compounds (ingredients) and their potential chemical derivatives with anticancer properties, some of which are already in clinical use. Bei-Mu (BM), Jie-Geng (JG), and Mai-Men-Dong-Tang (MMDT) are important CHMs prescribed for patients with lung cancer that have improved the survival rate.

HYPOTHESIS/PURPOSE

The aim of this study was to systemically investigate the mechanisms of action of these CHM products in lung cancer cells.

METHODS

We used a network pharmacology approach to study CHM product-related natural compounds and their lung cancer targets. In addition, the underlying anti-lung cancer effects of the natural compounds on apoptosis, cell cycle progression, autophagy, and the expression of related proteins was investigated in vitro.

RESULTS

Ingredient-lung cancer target network analysis identified 20 natural compounds. Three of these compounds, ursolic acid, 2-(3R)-8,8-dimethyl-3,4-dihydro-2H-pyrano(6,5-f)chromen-3-yl)-5-methoxyphenol, and licochalcone A, inhibited the proliferation of A549 lung cancer cells in a dose-dependent manner. Signal pathway analyses suggested that these three ingredients may target cellular apoptosis, anti-apoptosis, and cell cycle-related proteins. These three ingredients induced apoptosis through the regulation of the expression of apoptotic and anti-apoptotic proteins, including B-cell lymphoma-2 and full-length and cleaved poly(ADP-ribose) polymerase proteins. They also induced cell cycle arrest in S and G2/M phases and autophagy in A549 cells.

CONCLUSION

The pharmacological mechanisms of ingredients from MMDT on lung cancer may be strongly associated with their modulatory effects on apoptosis, autophagy, cell cycle progression, and cell proliferation.

Licochalcone A Inhibits Cellular Motility by Suppressing E-cadherin and MAPK Signaling in Breast Cancer

A compound isolated from Glycyrrhiza uralensis, licochalcone A (LA) exhibits anti-inflammatory and anti-tumor properties in various cell lines. LA has been found to promote autophagy and suppress specificity protein 1, inducing apoptosis in breast cancer cells. However, the regulation of breast cancer cell invasion and migration by LA is elusive. Thus, the present study investigated whether LA induces apoptosis and cellular motility in MDA-MB-231 breast cells, and investigated the underlying molecular mechanisms. MDA-MB-231 cells treated with LA and cell viability measured by cell counting kit-8 assay. Apoptotic signal proteins checked by flow cytometry, fluorescent staining, and Western blot. LA effectively suppressed cell migration, and modulated E-cadherin and vimentin expression by blocking MAPK and AKT signaling. LA inhibited cell proliferation and cell cycle, modulated mitochondrial membrane potential and DNA damage, and reduced oxidative stress in MDA-MB-231 cells. LA also activated cleaved-caspase 3 and 9, significantly decreased Bcl-2 expression, ultimately causing the release of cytochrome c from the mitochondria into the cytoplasm. Overall, our findings suggest that LA decreases cell proliferation and increases reactive oxygen species production for induced apoptosis, and regulates E-cadherin and vimentin by reducing MAPK and AKT signaling, resulting in suppressed MDA-MB-231 cell migration and invasion.

Licochalcone A Protects the Blood-Milk Barrier Integrity and Relieves the Inflammatory Response in LPS-Induced Mastitis

Background/Aims: Mastitis is an acute clinical inflammatory response. The occurrence and development of mastitis seriously disturb women's physical and mental health. Licochalcone A, a phenolic compound in Glycyrrhiza uralensis, has anti-inflammatory properties. Here, we examined the effect of licochalcone A on blood-milk barrier and inflammatory response in LPS-induced mice mastitis.

Methods:In vivo, we firstly established mice models of mastitis by canal injection of LPS to mammary gland, and then detected the effect of licochalcone A on pathological indexes, inflammatory responses and blood-milk barrier in this model. In vivo, Mouse mammary epithelial cells (mMECs) were treated with licochalcone A prior to the incubation of LPS, and then the inflammatory responses, tight junction which is the basic structure of blood-milk barrier were analyzed. Last, we elucidated the anti-inflammatory mechanism by examining the activation of mitogen-activated protein kinase (MAPK) and AKT/NF-κB signaling pathways in vivo and in vitro.

Result: The in vivo results showed that licochalcone A significantly decreased the histopathological impairment and the inflammatory responses, and improved integrity of blood-milk barrier. The in vitro results demonstrated that licochalcone A inhibited LPS-induced inflammatory responses and increase the protein levels of ZO-1, occludin, and claudin3 in mMECs. The in vivo and in vitro mechanistic study found that the anti-inflammatory effect of licochalcone A in LPS-induced mice mastitis was mediated by MAPK and AKT/NF-κB signaling pathways.

Conclusions and Implications: Our experiments collectively indicate that licochalcone A protected against LPS-induced mice mastitis via improving the blood–milk barrier integrity and inhibits the inflammatory response by MAPK and AKT/NF-κB signaling pathways.

Licochalcone A attenuates glioma cell growth in vitro and in vivo through cell cycle arrest

Licochalcone A (LA), an active ingredient of licorice, has multiple biological activities, including antioxidative and anti-inflammatory activities. Although LA exerts antitumor effects in various cancer cells, its role in gliomas remains unclear. Therefore, this study determined whether LA inhibits glioma cell growth in vitro and in vivo. The present data revealed that LA effectively inhibited the growth of U87 glioma cells by inducing cell cycle arrest in the G0/G1 and G2/M phases; cell cycle arrest was attributed to the LA-mediated reduction of mRNA and protein levels of cyclins and cyclin-dependent kinases. Moreover, subcutaneous (flank) and orthotopic (brain) tumor models were used to determine the role of LA in gliomas. LA significantly alleviated tumor growth in both models. These findings indicate that LA exerts antitumor effects in gliomas in vitro and in vivo and that it is a potential agent for treating glioblastoma multiforme.

Quantitative Proteomic Profiling Reveals Key Pathways in the Anticancer Action of Methoxychalcone Derivatives in Triple Negative Breast Cancer

Triple negative breast cancer is an aggressive, heterogeneous disease with high recurrence and metastasis rates even with modern chemotherapy regimens and thus is in need of new therapeutics. Here, three novel synthetic analogues of chalcones, plant-based molecules that have demonstrated potency against a wide variety of cancers, were investigated as potential therapeutics for triple negative breast cancer. These compounds exhibit IC₅₀ values of ∼5 μM in triple negative breast cancer cell lines and are more potent against triple negative breast cancer cell lines than against nontumor breast cell lines according to viability experiments. Tandem mass tag-based quantitative proteomics followed by gene set enrichment analysis and validation experiments using flow cytometry, apoptosis, and Western blot assays revealed three different anticancer mechanisms for these compounds. First, the chalcone analogues induce the unfolded protein response followed by apoptosis. Second, increases in the abundances of MHC-I pathway proteins occurs, which would likely result in immune stimulation in an organism. And third, treatment with the chalcone analogues causes disruption of the cell cycle by interfering with microtubule structure and by inducing G1 phase arrest. These data demonstrate the potential of these novel chalcone derivatives as treatments for triple negative breast cancer, though further work evaluating their efficacy in vivo is needed.

Mithramycin A suppresses basal triple-negative breast cancer cell survival partially via down-regulating Krüppel-like factor 5 transcription by Sp1

As the most malignant breast cancer subtype, triple-negative breast cancer (TNBC) does not have effective targeted therapies clinically to date. As a selective Sp1 inhibitor, Mithramycin A (MIT) has been reported to have anti-tumor activities in multiple cancers. However, the efficacy and the mechanism of MIT in breast cancer, especially TNBC, have not been studied. In this study, we demonstrated that MIT suppressed breast cancer cell survival in a dosage-dependent manner. Interestingly, TNBC cells were more sensitive to MIT than non-TNBC cells. MIT inhibited TNBC cell proliferation and promoted apoptosis in vitro in time- and dosage-dependent manners. MIT suppressed TNBC cell survival, at least partially, by transcriptionally down-regulating KLF5, an oncogenic transcription factor specifically expressed in basal TNBC. Finally, MIT suppressed TNBC cell growth in a xenograft mouse model. Taken together, our findings suggested that MIT inhibits basal TNBC via the Sp1/KLF5 axis and that MIT may be used for TNBC treatment.

A green and facile preparation approach, licochalcone A capped on hollow gold nanoparticles, for improving the solubility and dissolution of anticancer natural product

This study described a valuable drug delivery system for poorly water-soluble anticancer naturalproduct, licochalcone A, isolated from Glycyrrhiza inflata, loaded on hollow gold nanoparticles by green method to improve solubility and dissolution and maintain its natural pharmacological property. Briefly, the formation of hollow gold nanoparticles involves three steps: preparing of silica nanospheres by Stober method, forming of a thick gold shell around the silica templates and etching of silica particles by HF solution. Hollow gold nanoparticles (HGNPs) and drug loaded hollow gold nanoparticles (L-HGNPs) displayed spherical structure and approximately 200nm in size observed by SEM, XRD, EDS and DSC analysis showed that HGNPs were gold hollow structure and crystalline form. The solubility in aqueous solution of licochalcone A was increased obviously to 488.9 μg/ml, compared with free drugs of 136.1 μg/ml. Another interesting finding is that near-infrared (NIR) irradiation increased the speed of solubility of licochalcone A in aqueous solutions, rather than quantity. In short, the method of nano-delivery system combined with poorly water-soluble drug to improve its solubility and dissolution is worth applying to other natural products in order to increase their opportunities in clinical applications.