Baicalein, as a Prooxidant, Triggers Mitochondrial Apoptosis in MCF-7 Human Breast Cancer Cells Through Mobilization of Intracellular Copper and Reactive Oxygen Species Generation

Natural products for enhancing the sensitivity or decreasing the adverse effects of anticancer drugs through regulating the redox balance

Redox imbalance is reported to play a pivotal role in tumorigenesis, cancer development, and drug resistance. Severe oxidative damage is a general consequence of cancer cell responses to treatment and may cause cancer cell death or severe adverse effects. To maintain their longevity, cancer cells can rescue redox balance and enter a state of resistance to anticancer drugs. Therefore, targeting redox signalling pathways has emerged as an attractive and prospective strategy for enhancing the efficacy of anticancer drugs and decreasing their adverse effects. Over the past few decades, natural products (NPs) have become an invaluable source for developing new anticancer drugs due to their high efficacy and low toxicity. Increasing evidence has demonstrated that many NPs exhibit remarkable antitumour effects, whether used alone or as adjuvants, and are emerging as effective approaches to enhance sensitivity and decrease the adverse effects of conventional cancer therapies by regulating redox balance. Among them are several novel anticancer drugs based on NPs that have entered clinical trials. In this review, we summarize the synergistic anticancer effects and related redox mechanisms of the combination of NPs with conventional anticancer drugs. We believe that NPs targeting redox regulation will represent promising novel candidates and provide prospects for cancer treatment in the future.

Baicalein triggers ferroptosis in colorectal cancer cells via blocking the JAK2/STAT3/GPX4 axis

Colorectal cancer (CRC) is a prevalent form of gastrointestinal malignancy with challenges in chemotherapy resistance and side effects. Effective and low toxic drugs for CRC treatment are urgently needed. Ferroptosis is a novel mode of cell death, which has garnered attention for its therapeutic potential against cancer. Baicalein (5, 6, 7-trihydroxyflavone) is the primary flavone extracted from the dried roots of Scutellaria baicalensis that exhibits anticancer effects against several malignancies including CRC. In this study, we investigated whether baicalein induced ferroptosis in CRC cells. We showed that baicalein (1-64 μM) dose-dependently inhibited the viability of human CRC lines HCT116 and DLD1. Co-treatment with the ferroptosis inhibitor liproxstatin-1 (1 μM) significantly mitigated baicalein-induced CRC cell death, whereas autophagy inhibitor chloroquine (25 μM), necroptosis inhibitor necrostatin-1 (10 μM), or pan-caspase inhibitor Z-VAD-FMK (10 μM) did not rescue baicalein-induced CRC cell death. RNA-seq analysis confirmed that the inhibitory effect of baicalein on CRC cells is associated with ferroptosis induction. We revealed that baicalein (7.5-30 μM) dose-dependently decreased the expression levels of GPX4, key regulator of ferroptosis, in HCT116 and DLD1 cells by blocking janus kinase 2 (JAK2)/STAT3 signaling pathway via direct interaction with JAK2, ultimately leading to ferroptosis in CRC cells. In a CRC xenograft mouse model, administration of baicalein (10, 20 mg/kg, i.g., every two days for two weeks) dose-dependently inhibited the tumor growth with significant ferroptosis induced by inhibiting the JAK2/STAT3/GPX4 axis in tumor tissue. This study demonstrates that ferroptosis contributes to baicalein-induced anti-CRC activity through blockade of the JAK2/STAT3/GPX4 signaling pathway, which provides evidence for the therapeutic application of baicalein against CRC.

Integrated network pharmacology and metabolomics to reveal the mechanism of Pinellia ternata inhibiting non-small cell lung cancer cells

Lung cancer is a malignant tumor with highly heterogeneous characteristics. A classic Chinese medicine, Pinellia ternata (PT), was shown to exert therapeutic effects on lung cancer cells. However, its chemical and pharmacological profiles are not yet understood. In the present study, we aimed to reveal the mechanism of PT in treating lung cancer cells through metabolomics and network pharmacology. Metabolomic analysis of two strains of lung cancer cells treated with Pinellia ternata extracts (PTE) was used to identify differentially abundant metabolites, and the metabolic pathways associated with the DEGs were identified by MetaboAnalyst. Then, network pharmacology was applied to identify potential targets against PTE-induced lung cancer cells. The integrated network of metabolomics and network pharmacology was constructed based on Cytoscape. PTE obviously inhibited the proliferation, migration and invasion of A549 and NCI-H460 cells. The results of the cellular metabolomics analysis showed that 30 metabolites were differentially expressed in the lung cancer cells of the experimental and control groups. Through pathway enrichment analysis, 5 metabolites were found to be involved in purine metabolism, riboflavin metabolism and the pentose phosphate pathway, including D-ribose 5-phosphate, xanthosine, 5-amino-4-imidazolecarboxyamide, flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). Combined with network pharmacology, 11 bioactive compounds were found in PT, and networks of bioactive compound-target gene-metabolic enzyme-metabolite interactions were constructed. In conclusion, this study revealed the complicated mechanisms of PT against lung cancer. Our work provides a novel paradigm for identifying the potential mechanisms underlying the pharmacological effects of natural compounds.

The most recent progress of baicalein in its anti-neoplastic effects and mechanisms

Problems, such as toxic side effects and drug resistance of chemoradiotherapy, target therapy and immunotherapy accompanying the current anti-cancer treatments, have become bottlenecks limiting the clinical benefit for patients. Therefore, it is urgent to find promising anti-cancer strategies with higher efficacy and lesser side effects. Baicalein, a flavonoid component derived from the Chinese medicine scutellaria baicalensis, has been widely studied for its remarkable anti-cancer activity in multiple types of malignancies both at the molecular and cellular levels. Baicalein exerts its anti-tumor effects by inhibiting angiogenesis, invasion and migration, inducing cell apoptosis and cell cycle arrest, as well as regulating cell autophagy, metabolism, the tumor microenvironment and cancer stem cells with no obvious toxic side effects. The role of classic signaling pathways, such as PI3K/AKT/mTOR, MAPK, AMPK, Wnt/β-catenin, JAK/STAT3, MMP-2/-9, have been highlighted as the major targets for baicalein exerting its anti-malignant potential. Besides, baicalein can regulate the relevant non-coding RNAs, such as lncRNAs, miRNAs and circ-RNAs, to inhibit tumorigenesis and progression. In addition to the mentioned commonalities, baicalein shows some specific anti-tumor characteristics in some specific cancer types. Moreover, the preclinical studies of the combination of baicalein and chemoradiotherapy pave the way ahead for developing baicalein as an adjunct treatment with chemoradiotherapy. Our aim is to summary the role of baicalein in different types of cancer with its mechanisms based on in vitro and in vivo experiments, hoping providing proof for baicalein serving as an effective and safe compound for cancer treatment in clinic in the future.

Baicalin and Baicalein Enhance Cytotoxicity, Proapoptotic Activity, and Genotoxicity of Doxorubicin and Docetaxel in MCF-7 Breast Cancer Cells

Breast cancer is a major health concern and the leading cause of death among women worldwide. Standard treatment often involves surgery, radiotherapy, and chemotherapy, but these come with side effects and limitations. Researchers are exploring natural compounds like baicalin and baicalein, derived from the Scutellaria baicalensis plant, as potential complementary therapies. This study investigated the effects of baicalin and baicalein on the cytotoxic, proapoptotic, and genotoxic activity of doxorubicin and docetaxel, commonly used chemotherapeutic drugs for breast cancer. The analysis included breast cancer cells (MCF-7) and human endothelial cells (HUVEC-ST), to assess potential effects on healthy tissues. We have found that baicalin and baicalein demonstrated cytotoxicity towards both cell lines, with more potent effects observed in baicalein. Both flavonoids, baicalin (167 µmol/L) and baicalein (95 µmol/L), synergistically enhanced the cytotoxic, proapoptotic, and genotoxic activity of doxorubicin and docetaxel in breast cancer cells. In comparison, their effects on endothelial cells were mixed and depended on concentration and time. The results suggest that baicalin and baicalein might be promising complementary agents to improve the efficacy of doxorubicin and docetaxel anticancer activity. However, further research is needed to validate their safety and efficacy in clinical trials.

Baicalein Alleviates Arsenic-induced Oxidative Stress through Activation of the Keap1/Nrf2 Signalling Pathway in Normal Human Liver Cells

BACKGROUND

Oxidative stress is a key mechanism underlying arsenicinduced liver injury, the Kelch-like epichlorohydrin-related protein 1 (Keap1)/nuclear factor E2 related factor 2 (Nrf2) pathway is the main regulatory pathway involved in antioxidant protein and phase II detoxification enzyme expression. The aim of the present study was to investigate the role and mechanism of baicalein in the alleviation of arsenic-induced oxidative stress in normal human liver cells.

METHODS

Normal human liver cells (MIHA cells) were treated with NaAsO2 (0, 5, 10, 20 μM) to observe the effect of different doses of NaAsO2 on MIHA cells. In addition, the cells were treated with DMSO (0.1%), NaAsO2 (20 μM), or a combination of NaAsO2 (20 μM) and Baicalein (25, 50 or 100 μM) for 24 h to observe the antagonistic effect of Baicalein on NaAsO2. Cell viability was determined using a Cell Counting Kit- 8 (CCK-8 kit). The intervention doses of baicalein in subsequent experiments were determined to be 25, 50 and 100μM. The intracellular content of reactive oxygen species (ROS) was assessed using a 2',7'-dichlorodihydrofluorescein diacetate (DCFHDA) probe kit. The malonaldehyde (MDA), Cu-Zn superoxide dismutase (Cu-Zn SOD) and glutathione peroxidase (GSH-Px) activities were determined by a test kit. The expression levels of key genes and proteins were determined by real-time fluorescence quantitative polymerase chain reaction (qPCR) and Western blotting.

RESULTS

Baicalein upregulated the protein expression levels of phosphorylated Nrf2 (p-Nrf2) and nuclear Nrf2, inhibited the downregulation of Nrf2 target genes induced by arsenic, and decreased the production of ROS and MDA. These results demonstrate that baicalein promotes Nrf2 nuclear translocation by upregulating p-Nrf2 and inhibiting the downregulation of Nrf2 target genes in arsenic-treated MIHA cells, thereby enhancing the antioxidant capacity of cells and reducing oxidative stress.

CONCLUSION

Baicalein alleviated arsenic-induced oxidative stress through activation of the Keap1/Nrf2 signalling pathway in normal human liver cells.

Mechanism Research of PZD Inhibiting Lung Cancer Cell Proliferation, Invasion, and Migration based on Network Pharmacology

BACKGROUND

A classic Chinese medicine decoction, Pinellia ternata (Thunb.) Breit.-Zingiber officinale Roscoe (Ban-Xia and Sheng-Jiang in Chinese) decoction (PZD), has shown significant therapeutic effects on lung cancer.

OBJECTIVE

This study aimed to explore and elucidate the mechanism of action of PZD on lung cancer using network pharmacology methods.

METHODS

Active compounds were selected according to the ADME parameters recorded in the TCMSP database. Potential pathways related to genes were identified through GO and KEGG analysis. The compoundtarget network was constructed by using Cytoscape 3.7.1 software, and the core common targets were obtained by protein-protein interaction (PPI) network analysis. Batch molecular docking of small molecule compounds and target proteins was carried out by using the AutoDock Vina program. Different concentrations of PZD water extracts (10, 20, 40, 80, and 160 μg/mL) were used on lung cancer cells. Moreover, MTT and Transwell experiments were conducted to validate the prominent therapeutic effects of PZD on lung cancer cell H1299.

RESULTS

A total of 381 components in PZD were screened, of which 16 were selected as bioactive compounds. The compound-target network consisting of 16 compounds and 79 common core targets was constructed. MTT experiment showed that the PZD extract could inhibit the cell proliferation of NCI-H1299 cells, and the IC50 was calculated as 97.34 ± 6.14 μg/mL. Transwell and wound-healing experiments showed that the PZD could significantly decrease cell migration and invasion at concentrations of 80 and 160 μg/mL, respectively. The in vitro experiments confirmed that PZD had significant therapeutic effects on lung cancer cells, mainly through the PI3K/AKT signaling pathway.

CONCLUSION

PZD could inhibit the cell proliferation, migration, and invasion of NCI-H1299 cells partially through the PI3K/AKT signaling pathway. These findings suggested that PZD might be a potential treatment strategy for lung cancer patients.

Progress in the research of cuproptosis and possible targets for cancer therapy

Developing novel cancer therapies that exploit programmed cell death pathways holds promise for advancing cancer treatment. According to a recently published study in Science, copper death (cuproptosis) occurs when intracellular copper is overloaded, triggering aggregation of lipidated mitochondrial proteins and Fe-S cluster proteins. This intriguing phenomenon is triggered by the instability of copper ions. Understanding the molecular mechanisms behind cuproptosis and its associated genes, as identified by Tsvetkov, including ferredoxin 1, lipoic acid synthase, lipoyltransferase 1, dihydrolipid amide dehydrogenase, dihydrolipoamide transacetylase, pyruvate dehydrogenase α1, pyruvate dehydrogenase β, metallothionein, glutaminase, and cyclin-dependent kinase inhibitor 2A, may open new avenues for cancer therapy. Here, we provide a new understanding of the role of copper death and related genes in cancer.

Ratiometric codelivery of Paclitaxel and Baicalein loaded nanoemulsion for enhancement of breast cancer treatment

The most prevalent clinical option for treating cancer is combination chemotherapy. In combination therapy, assessment and optimization for obtaining a synergistic ratio could be obtained by various preclinical setups. Currently, in vitro optimization is used to get synergistic cytotoxicity while constructing combinations. Herein, we co-encapsulated Paclitaxel (PTX) and Baicalein (BCLN) with TPP-TPGS1000 containing nanoemulsion (TPP-TPGS1000-PTX-BCLN-NE) for breast cancer treatment. The assessment of cytotoxicity of PTX and BCLN at different molar weight ratios provided an optimized synergistic ratio (1:5). Quality by Design (QbD) approach was later applied for the optimization as well as characterization of nanoformulation for its droplet size, zeta potential and drug content. TPP-TPGS1000-PTX-BCLN-NE significantly enhanced cellular ROS, cell cycle arrest, and depolarization of mitochondrial membrane potential in the 4T1 breast cancer cell line compared to other treatments. In the syngeneic 4T1 BALB/c tumor model, TPP-TPGS1000-PTX-BCLN-NE outperformed other nanoformulation treatments. The pharmacokinetic, biodistribution and live imaging studies pivoted TPP-TPGS1000-PTX-BCLN-NE enhanced bioavailability and PTX accumulation at tumor site. Later, histology studies confirmed nanoemulsion non-toxicity, expressing new opportunities and potential to treat breast cancer. These results suggested that current nanoformulation can be a potential therapeutic approach to effectively address breast cancer therapy.

Moringa oleifera: A Review on the Antiproliferative Potential in Breast Cancer Cells

The global burden of female breast cancer and associated deaths has become a major concern. Many chemotherapeutic agents, such as doxorubicin, have been shown to have adverse side effects. The development of multi-drug resistance is a common occurrence, contributing to chemotherapeutic failure. The resistance of breast cancer cells to drug treatment leads to a decline in the treatment efficacy and an increase in cancer recurrence. Therefore, action is required to produce alternative drug therapies, such as herbal drugs. Herbal drugs have been proven to be beneficial in treating illnesses, including cancer. This review aims to highlight the antiproliferative potential of Moringa oleifera (MO), a medicinal tree native to India and indigenous to Africa, in breast cancer cells. Although MO is not yet considered a commercial chemopreventive drug, previous studies have indicated that it could become a chemotherapeutic agent. The possible antiproliferative potential of MO aqueous leaf extract has been previously proven through its antioxidant potential as well as its ability to induce apoptosis. This review will provide an increased understanding of the effect that MO aqueous leaf extract could potentially have against breast cancer.

Mitochondria Deregulations in Cancer Offer Several Potential Targets of Therapeutic Interventions

Mitochondria play a key role in cancer and their involvement is not limited to the production of ATP only. Mitochondria also produce reactive oxygen species and building blocks to sustain rapid cell proliferation; thus, the deregulation of mitochondrial function is associated with cancer disease development and progression. In cancer cells, a metabolic reprogramming takes place through a different modulation of the mitochondrial metabolic pathways, including oxidative phosphorylation, fatty acid oxidation, the Krebs cycle, glutamine and heme metabolism. Alterations of mitochondrial homeostasis, in particular, of mitochondrial biogenesis, mitophagy, dynamics, redox balance, and protein homeostasis, were also observed in cancer cells. The use of drugs acting on mitochondrial destabilization may represent a promising therapeutic approach in tumors in which mitochondrial respiration is the predominant energy source. In this review, we summarize the main mitochondrial features and metabolic pathways altered in cancer cells, moreover, we present the best known drugs that, by acting on mitochondrial homeostasis and metabolic pathways, may induce mitochondrial alterations and cancer cell death. In addition, new strategies that induce mitochondrial damage, such as photodynamic, photothermal and chemodynamic therapies, and the development of nanoformulations that specifically target drugs in mitochondria are also described. Thus, mitochondria-targeted drugs may open new frontiers to a tailored and personalized cancer therapy.

Baicalin enhances the efficacy of 5-Fluorouracil in gastric cancer by promoting ROS-mediated ferroptosis

BACKGROUND

5-Fluorouracil (5-Fu) is one of the most commonly used chemotherapy drugs for gastric cancer (GC). But the increase of drug resistance makes the prognosis of patients worse. Studies have shown that Baicalin can not only inhibit various cancers but also increase the sensitivity of cancers to chemotherapy. However, how Baicalin works in chemotherapeutic resistance of GC are unclear.

METHODS

CCK8 (Cell Counting Kit 8) was used to detect the IC50 (half maximal inhibitory concentration) of Baicalin and 5-Fu. Proliferation, migration, and invasion of GC were tested through colony formation assay and transwell assay. Fluorescent probes detected intracellular reactive oxygen species (ROS). RNA-seq (RNA sequencing) detected differentially expressed genes and pathways, and qPCR (Quantitative Real-time PCR) tested the expression of ferroptosis-related genes.

RESULTS

The combination of Baicalin and 5-Fu inhibited GC progression and increased intracellular ROS levels. Both the inhibition of malignant phenotype of gastric cancer cells and the generation of intracellular ROS caused by Baicalin could be saved by the inhibitor of ferroptosis-Ferrostatin-1 (Fer-1). Heat map of enriched differentially expressed genes identified by RNA-seq included four ferroptosis-related genes, and subsequent GO (Gene Ontology) analysis suggested an association between the ferroptosis pathway and Baicalin treatment. The changes in expression of ferroptosis-related genes were validated by qPCR, and the result confirmed that the combination of Baicalin and 5-Fu promoted ferroptosis in GC.

CONCLUSIONS

Baicalin inhibits GC and enhances 5-Fu by promoting ROS-related ferroptosis in GC.

Baicalein as Promising Anticancer Agent: A Comprehensive Analysis on Molecular Mechanisms and Therapeutic Perspectives

Despite significant therapeutic advancements for cancer, an atrocious global burden (for example, health and economic) and radio- and chemo-resistance limit their effectiveness and result in unfavorable health consequences. Natural compounds are generally considered safer than synthetic drugs, and their use in cancer treatment alone, or in combination with conventional therapies, is increasingly becoming accepted. Interesting outcomes from pre-clinical trials using Baicalein in combination with conventional medicines have been reported, and some of them have also undergone clinical trials in later stages. As a result, we investigated the prospects of Baicalein, a naturally occurring substance extracted from the stems of Scutellaria baicalensis Georgi and Oroxylum indicum Kurz, which targets a wide range of molecular changes that are involved in cancer development. In other words, this review is primarily driven by the findings from studies of Baicalein therapy in several cancer cell populations based on promising pre-clinical research. The modifications of numerous signal transduction mechanisms and transcriptional agents have been highlighted as the major players for Baicalein’s anti-malignant properties at the micro level. These include AKT serine/threonine protein kinase B (AKT) as well as PI3K/Akt/mTOR, matrix metalloproteinases-2 & 9 (MMP-2 & 9), Wnt/-catenin, Poly(ADP-ribose) polymerase (PARP), Mitogen-activated protein kinase (MAPK), NF-κB, Caspase-3/8/9, Smad4, Notch 1/Hes, Signal transducer and activator of transcription 3 (STAT3), Nuclear factor erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein-1 (Keap 1), Adenosine monophosphate-activated protein kinase (AMPK), Src/Id1, ROS signaling, miR 183/ezrin, and Sonic hedgehog (Shh) signaling cascades. The promise of Baicalein as an anti-inflammatory to anti-apoptotic/anti-angiogenic/anti-metastatic medicinal element for treating various malignancies and its capability to inhibit malignant stem cells, evidence of synergistic effects, and design of nanomedicine-based drugs are altogether well supported by the data presented in this review study.

Baicalein Induces G2/M Cell Cycle Arrest Associated with ROS Generation and CHK2 Activation in Highly Invasive Human Ovarian Cancer Cells

Ovarian cancer is a lethal gynecological cancer because drug resistance often results in treatment failure. The CHK2, a tumor suppressor, is considered to be an important molecular target in ovarian cancer due to its role in DNA repair. Dysfunctional CHK2 impairs DNA damage-induced checkpoints, reduces apoptosis, and confers resistance to chemotherapeutic drugs and radiation therapy in ovarian cancer cells. This provides a basis for finding new effective agents targeting CHK2 upregulation or activation to treat or prevent the progression of advanced ovarian cancer. Here, the results show that baicalein (5,6,7-trihydroxyflavone) treatment inhibits the growth of highly invasive ovarian cancer cells, and that baicalein-induced growth inhibition is mediated by the cell cycle arrest in the G₂/M phase. Baicalein-induced G₂/M phase arrest is associated with an increased reactive oxygen species (ROS) production, DNA damage, and CHK2 upregulation and activation. Thus, baicalein modulates the expression of DNA damage response proteins and G₂/M phase regulatory molecules. Blockade of CHK2 activation by CHK2 inhibitors protects cells from baicalein-mediated G₂/M cell cycle arrest. All the results suggest that baicalein has another novel growth inhibitory effect on highly invasive ovarian cancer cells, which is partly related to G₂/M cell cycle arrest through the ROS-mediated DNA breakage damage and CHK2 activation. Collectively, our findings provide a molecular basis for the potential of baicalein as an adjuvant therapeutic agent in the treatment of metastatic ovarian cancer.

Advances in Anti-Cancer Activities of Flavonoids in Scutellariae radix: Perspectives on Mechanism

Despite encouraging progresses in the development of novel therapies, cancer remains the dominant cause of disease-related mortality and has become a leading economic and healthcare burden worldwide. Scutellariae radix (SR, Huangqin in Chinese) is a common herb used in traditional Chinese medicine, with a long history in treating a series of symptoms resulting from cancer, like dysregulated immune response and metabolic abnormalities. As major bioactive ingredients extracted from SR, flavonoids, including baicalein, wogonin, along with their glycosides (baicalin and wogonoside), represent promising pharmacological and anti-tumor activities and deserve extensive research attention. Emerging evidence has made great strides in elucidating the multi-targeting therapeutic mechanisms and key signaling pathways underlying the efficacious potential of flavonoids derived from SR in the field of cancer treatment. In this current review, we aim to summarize the pharmacological actions of flavonoids against various cancers in vivo and in vitro. Moreover, we also make a brief summarization of the endeavor in developing a drug delivery system or structural modification to enhance the bioavailability and biological activities of flavonoid monomers. Taken together, flavonoid components in SR have great potential to be developed as adjuvant or even primary therapies for the clinical management of cancers and have a promising prospect.

Baicalein may act as a caloric restriction mimetic candidate to improve the anti-oxidant profile in a natural rodent model of aging

INTRODUCTION

Caloric restriction (CR) is the most effective intervention for extending the life span of vertebrate and invertebrate aging models.. CRMs, which are synthetic or natural chemicals that mimic the biochemical, hormonal, and physiological consequences of calorie restriction, are being researched for anti-aging benefits. Baicalein is a plant-derived polyphenol that has the potential of anti-oxidant, anti-inflammatory, and autophagy inducer. The objective of this study is to evaluate the anti-aging, anti-inflammatory, and antioxidant role of Baicalein in erythrocyte membrane and plasma, and evaluate the efficacy of Baicalein to act as a CRM candidate.

MATERIALS AND METHODS

The present study evaluates the effect of Baicalein on aging biomarkers in normal and aged rats. We study various pro- and anti-oxidant markers, erythrocyte membrane transporters, and eryptosis.

RESULTS

Baicalein supplementation in male Wistar rats significantly alleviated pro-oxidant markers and improved anti-oxidant profile. Improvement was also observed in age-induced alterations in membrane transporters, and eryptosis.

CONCLUSION

Based on the above observations we conclude that Baicalein has the potential to maintain extracellular ROS levels and redox homeostasis during the aging process, an effect which is similar to CR. Thus Baicalein may be a potent CRM candidate for anti-aging interventions.

Promoting Apoptosis, a Promising Way to Treat Breast Cancer With Natural Products: A Comprehensive Review

Breast cancer is one of the top-ranked malignant carcinomas associated with morbidity and mortality in women worldwide. Chemotherapy is one of the main approaches to breast cancer treatment. Breast cancer initially responds to traditional first- and second-line drugs (aromatase inhibitor, tamoxifen, and carboplatin), but eventually acquires resistance, and certain patients relapse within 5 years. Chemotherapeutic drugs also have obvious toxic effects. In recent years, natural products have been widely used in breast cancer research because of their low side effects, low toxicity, and good efficacy based on their multitarget therapy. Apoptosis, a programmed cell death, occurs as a normal and controlled process that promotes cell growth and death. Inducing apoptosis is an important strategy to control excessive breast cancer cell proliferation. Accumulating evidence has revealed that natural products become increasingly important in breast cancer treatment by suppressing cell apoptosis. In this study, we reviewed current studies on natural product–induced breast cancer cell apoptosis and summarized the proapoptosis mechanisms including mitochondrial, FasL/Fas, PI3K/AKT, reactive oxygen species, and mitogen-activated protein kinase–mediated pathway. We hope that our review can provide direction in the search for candidate drugs derived from natural products to treat breast cancer by promoting cell apoptosis.

Copper-induced tumor cell death mechanisms and antitumor theragnostic applications of copper complexes

Recent studies found that unbalanced copper homeostasis affect tumor growth, causing irreversible damage. Copper can induce multiple forms of cell death, including apoptosis and autophagy, through various mechanisms, including reactive oxygen species accumulation, proteasome inhibition, and antiangiogenesis. Hence, copper in vivo has attracted tremendous attention and is in the research spotlight in the field of tumor treatment. This review first highlights three typical forms of copper's antitumor mechanisms. Then, the development of diverse biomaterials and nanotechnology allowing copper to be fabricated into diverse structures to realize its theragnostic action is discussed. Novel copper complexes and their clinical applications are subsequently described.

An In Vitro and In Silico Study of the Enhanced Antiproliferative and Pro-Oxidant Potential of Olea europaea L. cv. Arbosana Leaf Extract via Elastic Nanovesicles (Spanlastics)

The olive tree is a venerable Mediterranean plant and often used in traditional medicine. The main aim of the present study was to evaluate the effect of Olea europaea L. cv. Arbosana leaf extract (OLE) and its encapsulation within a spanlastic dosage form on the improvement of its pro-oxidant and antiproliferative activity against HepG-2, MCF-7, and Caco-2 human cancer cell lines. The LC-HRESIMS-assisted metabolomic profile of OLE putatively annotated 20 major metabolites and showed considerable in vitro antiproliferative activity against HepG-2, MCF-7, and Caco-2 cell lines with IC₅₀ values of 9.2 ± 0.8, 7.1 ± 0.9, and 6.5 ± 0.7 µg/mL, respectively. The encapsulation of OLE within a (spanlastic) nanocarrier system, using a spraying method and Span 40 and Tween 80 (4:1 molar ratio), was successfully carried out (size 41 ± 2.4 nm, zeta potential 13.6 ± 2.5, and EE 61.43 ± 2.03%). OLE showed enhanced thermal stability, and an improved in vitro antiproliferative effect against HepG-2, MCF-7, and Caco-2 (IC₅₀ 3.6 ± 0.2, 2.3 ± 0.1, and 1.8 ± 0.1 µg/mL, respectively) in comparison to the unprocessed extract. Both preparations were found to exhibit pro-oxidant potential inside the cancer cells, through the potential inhibitory activity of OLE against glutathione reductase and superoxide dismutase (IC₅₀ 1.18 ± 0.12 and 2.33 ± 0.19 µg/mL, respectively). These inhibitory activities were proposed via a comprehensive in silico study to be linked to the presence of certain compounds in OLE. Consequently, we assume that formulating such a herbal extract within a suitable nanocarrier would be a promising improvement of its therapeutic potential.

Targeting the redox imbalance in mitochondria: A novel mode for cancer therapy

Changes in reactive oxygen species (ROS) levels affect many aspects of cell behavior. During carcinogenesis, moderate ROS production modifies gene expression to alter cell function, elevating metabolic activity and ROS. To avoid extreme ROS-activated death, cancer cells increase antioxidative capacity, regulating sustained ROS levels that promote growth. Anticancer therapies are exploring inducing supranormal, cytotoxic oxidative stress levels either inhibiting antioxidative capacity or promoting excess ROS to selectively destroy cancer cells, triggering mechanisms such as apoptosis, autophagy, necrosis, or ferroptosis. This review exemplifies pro-oxidants (natural/synthetic/repurposed drugs) and their clinical significance as cancer therapies providing revolutionary approaches.

Small molecules baicalein and cinnamaldehyde are potentiators of measles virus-induced breast cancer oncolysis

BACKGROUND

Although the breast cancer mortality has slowed down from 2008 to 2017, breast cancer incidence rate continues to rise and thus, new and/or improved treatments are highly needed. Among them, oncolytic virotherapy which has the ability of facilitating the antitumor adaptive immunity, appears as a promising anticancer therapy. Oncolytic measles virus (MV) is particularly suitable for targeting breast cancer due to the upregulation of MV's receptor nectin-4. Nonetheless, with limited clinical success currently, ways of boosting MV-induced breast cancer oncolysis are therefore necessary. Oncolytic virotherapy alone and combined with chemotherapeutic drugs are two strategic areas with intensive development for the search of anticancer drugs. Considering that baicalein (BAI) and cinnamaldehyde (CIN) have demonstrated antitumor properties against multiple cancers including breast cancer, they could be good partners for MV-based oncolytic virotherapy.

PURPOSE

To assess the in vitro effect of BAI and CIN with MV and assess their combination effects.

METHODS

We examined the combinatorial cytotoxic effect of oncolytic MV and BAI or CIN on MCF-7 breast cancer cells. Potential anti-MV activities of the phytochemicals were first investigated in vitro to determine the optimal combination model. Synergism of MV and BAI or CIN was then evaluated in vitro by calculating the combination indices. Finally, cell cycle analysis and apoptosis assays were performed to confirm the mechanism of synergism.

RESULTS

Overall, the viral sensitization combination modality using oncolytic MV to first infect MCF-7 breast cancer cells followed by drug treatment with BAI or CIN was found to produce significantly enhanced tumor killing. Further mechanistic studies showed that the combinations 'MV-BAI' and 'MV-CIN' display synergistic anti-breast cancer effect, mediated by elevated apoptosis.

CONCLUSION

We demonstrated, for the first time, effective combination of oncolytic MV with BAI or CIN that could be further explored and potentially developed into novel therapeutic strategies targeting nectin-4-marked breast cancer cells.

Baicalin triggers apoptosis, inhibits migration, and enhances anti-tumor immunity in colorectal cancer via TLR4/NF-κB signaling pathway

Aberrant activation of the nuclear factor-kappa B (NF-κB) signaling pathway is closely implicated in colorectal cancer (CRC) growth, metastasis, and immune escape. In the present study, we reported natural derived compound of baicalin (BA), an efficient inhibitor of NF-κB, with good anti-tumor effect on CRC. CCK8 and colony formation assays showed that Baicalin significantly inhibit viability and proliferation in HCT-116 and CT26 cells. Additionally, Baicalin dramatically triggers mitochondria-mediated apoptosis in both HCT-116 and CT-26 cells, which is evidenced by loss of mitochondrial membrane potential and elevated cellular reactive oxygen species level. Treatment with Baicalin suppresses migration and invasion of CT26 cells by impairing TLR4/NF-κB signaling pathway. What's more, administration of Baicalin significantly retarded tumor growth rate in a subcutaneous xenograft tumor mouse model of CT26 cells. Treatment with Baicalin could ameliorate tumor immunosuppressive environment by downregulation of PD-L1 expression and proportion of myeloid-derived suppressor cells (MDSCs) and upregulation of percent of CD4⁺ and CD8⁺ T cells in CT26 tumors, thus improving anti-tumor immunity. In conclusion, our study demonstrated that baicalin triggers apoptosis, inhibits migration, and enhances anti-tumor immunity in colorectal cancer via TLR4/NF-κB signaling pathway, suggesting it might serve as a potential candidate drug for the treatment of CRC. PRACTICAL APPLICATIONS: In the present study, we reported natural derived compound of baicalin (BA), an efficient inhibitor of NF-κB, with good anti-tumor effect on CRC. We demonstrated that baicalin triggers mitochondria-mediated apoptosis, inhibits migration, and improves anti-tumor immunity in colorectal cancer via TLR4/NF-κB signaling pathway.

Black pepper and piperine induce anticancer effects on leukemia cell line

The black pepper, most commonly used in Indian cuisines for ages, is considered as "king of spices." The present study evaluates the anticancer potential of black pepper and its main constituent, i.e. alkaloid piperine, against human leukemia cell line, K-562 cells. Gas chromatography-mass spectrometry (GC-MS) analysis confirmed the presence of piperine in black pepper extract. The methanolic extract of black pepper (BP-M) and pure piperine (PIP) showed a strong cytotoxic effect against this cell line. Both BP-M and PIP generated apoptotic bodies in K-562 cells and caused nuclear condensation as visualized by fluorescent microscopy, which was further confirmed by flow cytometry analysis. BP-M and PIP also generated reactive oxygen species in K-562 cells as established by flow cytometry. The translation of Bax, caspase-3 and caspase-9 genes was found to be upregulated with subsequent downregulation of Bcl-2 gene. The anti-proliferative effect of both BP-M and PIP was also observed by trypan blue staining and was further confirmed by the downregulated expression of proliferating cell nuclear antigen (PCNA). The molecular docking studies showed the binding of PIP with PCNA and Bcl-2 and supported the in vitro findings. The docking studies also proposed the binding of PIP to ADP binding pocket of Apaf-1 protein. Taken together, these findings signify the anticancer potential of both black pepper and PIP, thus proposing black pepper as a potent nutraceutical for preventing the progression of chronic myeloid leukemia.

Baicalein Represses Cervical Cancer Cell Growth, Cell Cycle Progression and Promotes Apoptosis via Blocking AKT/mTOR Pathway by the Regulation of circHIAT1/miR-19a-3p Axis

Background

Baicalein has a significant anti-cancerous function in the treatment of cervical cancer (CC). Its functional mechanism regarding circular RNA (circRNA) hippocampus abundant transcript 1 (circHIAT1) and microRNA-19a-3p (miR-19a-3p) was explored in this research.

Methods

CC cell viability and colony formation were determined using Cell Counting Kit-8 (CCK-8) and colony formation assay. Cell cycle progression and apoptosis were analyzed via flow cytometry. Protein markers of cell cycle, apoptosis and protein kinase B/mammalian target of rapamycin (AKT/mTOR) pathway were detected by Western blot. CircHIAT1 and miR-19a-3p levels were assayed through the quantitative real-time polymerase chain reaction (qRT-PCR). The interaction between circHIAT1 and miR-19a-3p was validated by dual-luciferase reporter and RNA pull-down assays. In vivo experiment was performed by xenograft model.

Results

CC cell growth and cell cycle progression were repressed while apoptosis was enhanced by baicalein. MiR-19a-3p was downregulated in baicalein-treated CC cells and miR-19a-3p overexpression lightened the baicalein-induced CC progression inhibition. Moreover, circHIAT1 was found to be a sponge of miR-19a-3p in CC cells. Baicalein-induced cell growth inhibition, cell cycle arrest and apoptosis promotion were neutralized by knockdown of circHIAT1 via targeting miR-19a-3p. Baicalein acted on the circHIAT1/miR-19a-3p to inactivate AKT/mTOR pathway. Baicalein also reduced CC tumor growth in vivo via regulating the levels of circHIAT1 and miR-19a-3p.

Conclusion

These findings demonstrated that the inhibitory function of baicalein in CC progression was dependent on the repression of AKT/mTOR pathway by upregulating circHIAT1 to sponge miR-19a-3p, showing a specific mechanism for baicalein in CC.

Baicalein suppresses growth of non-small cell lung carcinoma by targeting MAP4K3

Exploring key genes associated with non-small cell lung carcinoma (NSCLC) may lead to targeted therapies for NSCLC patients. The protein kinase MAP4K3 has been established as an important modulator of cell growth and autophagy in mammals. Herein, we investigated the somatic mutations and the expression pattern of MAP4K3 detected in NSCLC patients based on the TCGA database. Abnormal MAP4K3 expression and its somatic mutations are associated with the carcinogenesis and thereby becoming an attractive therapeutic target. Baicalein, a natural product, was determined to be the first-reported MAP4K3 binding ligand with its KD values of 6.47 μM measured by microscale thermophoresis. Subsequent in silico docking and mutation studies demonstrated that baicalein directly binds to MAP4K3, presumably to the substrate-binding pocket of this kinase domain, causing inactivity of MAP4K3. We further showed that baicalein could induce degradation of MAP4K3 through decreasing its stability and promoting the ubiquitin proteasome pathway. Degradation of MAP4K3 could cause dissociation of the transcription factor EB and 14-3-3 complex, enhance rapid transport of TFEB to the nucleus and trigger TFEB-dependent autophagy, resulting in lung cancer cells proliferation arrest. Knockdown of MAP4K3 expression by siRNA was sufficient to mimic baicalein-induced autophagy. Ectopic expression of the MAP4K3 protein resulted in significant resistance to baicalein-induced autophagy. Baicalein exhibited good tumor growth inhibition in a nude mouse model for human H1299 xenografts, which might be tightly related to its binding to MAP4K3 and degradation of MAP4K3. Our data provide novel mechanistic insights of baicalein/ MAP4K3/ mTORC1/ TFEB axis in regulating baicalein-induced autophagy in NSCLC, suggesting potential therapies for treatment of NSCLC.

Baicalein: A metabolite with promising antineoplastic activity

Cancer, being a multifactorial disease has diverse presentation in different subgroups which is mainly attributed to heterogenous presentation of tumor cells. This cancer cell heterogeneity is the major reason for variable response to standard chemotherapeutic regimes owing to which high relapse rate and multi-drug resistance has increasingly been reported over the past decade. Interestingly, the research on natural compounds in combination with standard therapies have reported with interesting and promising results from the pre-clinical trials and few of which have also been tested in other phases of clinical trials. This review focusses on baicalein, an emerging anti-cancerous natural compound, its chemistry and mechanism of action. In view of promising pre-clinical this review is mainly motivated by the results observed from baicalein treatment of different cancer cell population. With the advancing scientific evidence on the anti-malignant potential of baicalein with respect to its pharmacological activities encompassing from anti-inflammatory to anti-angiogenic/anti-metastatic effects, the focus is mainly directed to understanding the precise mechanism of action of baicalein. In the process of understanding the underlying signaling cascades, the role of mitogen activated protein kinase (MAPK), mammalian target of rapamycin (mTOR), AKT serine/threonine protein kinase B (AKT), poly(ADP-ribose) polymerase (PARP), matrix metalloproteinases-2 (MMP-2), matrix metalloproteinases-9 (MMP-9) and caspase-3/-8,-9 have been highlighted as the major players for baicalein anti-malignant potential. This is also supported by the interesting pre-clinical findings which cumulatively pave the way ahead for development of baicalein as an adjunct anti-cancer treatment with chemotherapeutic agents.

A Network Pharmacology Approach to Explore the Potential Mechanisms of Huangqin-Baishao Herb Pair in Treatment of Cancer

BACKGROUND The aim of this study was to identify the bioactive ingredients of Huangqin-Baishao herb pair and to reveal its anti-cancer mechanisms through a pharmacology approach. MATERIAL AND METHODS Detailed information on compounds in the HQ-BS herb pair was obtained from the Traditional Chinese medicine systems pharmacology (TCMSP) and screened by the criteria of OB ≥30% and DL ≥0.18. A systematic drug targeting model (SysDT) was used for compound targets prediction, and then the targets were analyzed for Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. The protein-protein interaction (PPI) network of HQ-BS targets was constructed, after identifying core networks through Cytoscape plugins. RESULTS We found 47 bioactive compounds of HQ-BS and 107 human-derived targets. A compound target network and a target signal pathway network were constructed and used for topological analysis. Kaempferol, beta-sitosterol, stigmasterol, wogonin, and oroxylin-a were identified as core compounds and pathways in cancer. The calcium signaling pathway, PI3K-Akt signaling pathway, TNF signaling pathway, chemical carcinogenesis, estrogen signaling pathway, proteoglycans in cancer, HIF-1 signaling pathway, thyroid hormone signaling pathway, VEGF signaling pathway, small cell lung cancer, prostate cancer, colorectal cancer, NOD-like receptor signaling pathway, and T cell receptor signaling pathway were found to be potential signals of HQ-BS in treating cancer. Through PPI network analysis, TNF signaling pathway, tryptophan metabolism, proteoglycans in cancer, cell cycle, and chemical carcinogenesis sub-networks were obtained. CONCLUSIONS HQ-BS contains various bioactive compounds, including flavonoids, phytosterols, and other compounds, and these compounds can inhibit or activate multiple targets and pathways against cancer.