Cepharanthine hydrochloride reverses the mdr1 (P-glycoprotein)-mediated esophageal squamous cell carcinoma cell cisplatin resistance through JNK and p53 signals

Cepharanthine sensitizes gastric cancer cells to chemotherapy by targeting TRIB3-FOXO3-FOXM1 axis to inhibit autophagy

BACKGROUND

Gastric cancer is among the common solid tumors. Chemotherapy resistance is the most common issue in gastric cancer treatment. Inhibiting intracellular autophagy may be a feasible method for overcoming chemotherapy resistance. Cepharanthine (CEP), a natural small molecule extracted from the stephania cephalantha Hayata plant, has been demonstrated to significantly inhibit cancer growth and can regulate autophagy. Although CEP can significantly inhibit cancer growth, it remains unclear whether CEP can regulate autophagy in gastric cancer. This study aimed to investigate whether CEP can enhance the sensitivity of gastric cancer to chemotherapy and elucidate its molecular mechanism.

METHODS

Three gastric cancer cell lines (AGS, SGC7901, and MFC) and one normal gastric mucosal epithelial cell line (GES-1) were used for in vitro experiments. The characterization of autophagy in gastric cancer cells included the detection of autophagy markers and autophagy flux through immunofluorescence staining and Western blotting, as well as the assessment of lysosomal function using fluorescence staining (LysoTracker Red DND-99, Acridine Orange staining) and Western blotting. The cytotoxicity of CEP, autophagy inhibitors (chloroquine [CQ] and 3-methyladenine [3MA]), and chemotherapy drugs (doxorubicin [DOX] and cisplatin [CIS]) was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, cell colony formation, and fluorescence staining techniques (H2DCFDA, Dihydroethidium, and JC-1 staining). The interaction between CEP and autophagy inhibitors was tested in a 615 mice model, and changes in the gut microbiota were determined through accurate 16S absolute quantification sequencing. The signaling pathway and autophagy regulatory target TRIB3-FOXO3-FOXM1 were confirmed through molecular docking, RNA sequencing, bioinformatic analysis, transfection techniques, and Western blotting.

RESULTS

CEP blocked autophagic flux in gastric cancer cells without affecting lysosomal function. As a novel autophagy inhibitor, CEP could combine with conventional autophagy inhibitors (CQ and 3MA) to block intracellular autophagy, thereby inhibiting gastric cancer growth. During this process, changes in the gut microbiota were observed, including low-level changes in Odoribacterium, Erysipelatoclostridium, and ParaPrevotella and high-level changes in Ileibacterium, Enterorhabdus, and Bifidobacterium. Additionally, CEP synergistically inhibited the growth of gastric cancer when combined with chemotherapy drugs. Mechanistically, the TRIB3-FOXO3-FOXM1 signaling axis was found to be involved in the inhibition of gastric cancer by CEP combined with autophagy inhibitors and chemotherapy drugs, thereby mediating cell apoptosis.

CONCLUSION

This study links the TRIB3-FOXO3-FOXM1 axis with chemotherapy efficacy. Our findings demonstrated that CEP inhibits autophagy by modulating the FOXO3-FOXM1 axis. When combined with chemotherapy drugs (DOX and CIS), CEP, as an autophagy inhibitor, can limit TRIB3 protein expression, thereby regulating the FOXO3-FOXM1 axis and enhancing its ability to prevent gastric cancer growth. These findings may contribute to improving the prognosis of patients with gastric cancer. Furthermore, these results enrich the fundamental understanding of how autophagy inhibition can enhance clinical cancer treatment efficacy and provide insights into the potential mechanisms by which CEP functions as an anti-tumor drug, thereby exploring its value for clinical application.

Mechanism of multidrug resistance to chemotherapy mediated by P‑glycoprotein (Review)

Multidrug resistance (MDR) seriously limits the clinical application of chemotherapy. A mechanism underlying MDR is the overexpression of efflux transporters associated with chemotherapeutic drugs. P‑glycoprotein (P‑gp) is an ATP‑binding cassette (ABC) transporter, which promotes MDR by pumping out chemotherapeutic drugs and reducing their intracellular concentration. To date, overexpression of P‑gp has been detected in various types of chemoresistant cancer and inhibiting P‑gp‑related MDR has been suggested. The present review summarizes the mechanisms underlying MDR mediated by P‑gp in different tumors and evaluated the related signaling pathways, with the aim of improving understanding of the current status of P‑gp‑mediated chemotherapeutic resistance. This review focuses on the main mechanisms of inhibiting P‑gp‑mediated MDR, with the aim of providing a reference for the study of reversing P‑gp‑mediated MDR. The first mechanism involves decreasing the efflux activity of P‑gp by altering its conformation or hindering P‑gp‑chemotherapeutic drug binding. The second inhibitory mechanism involves inhibiting P‑gp expression to reduce efflux. The third inhibitory mechanism involves knocking out the ABCB1 gene. Potential strategies that can inhibit P‑gp include certain natural products, synthetic compounds and biological techniques. It is important to screen lead compounds or candidate techniques for P‑gp inhibition, and to identify inhibitors by targeting the relevant signaling pathways to overcome P‑gp‑mediated MDR.

Research progress on pharmacological effects and mechanisms of cepharanthine and its derivatives

Cepharanthine (CEP) is a bisbenzylisoquinoline alkaloid compound found in plants of the Stephania genus, which has biological functions such as regulating autophagy, inhibiting inflammation, oxidative stress, and apoptosis. It is often used for the treatment of inflammatory diseases, viral infections, cancer, and immune disorders and has great clinical translational value. However, there is no detailed research on its specific mechanism and dosage and administration methods, especially clinical research is limited. In recent years, CEP has shown significant effects in the prevention and treatment of COVID-19, suggesting its potential medicinal value waiting to be discovered. In this article, we comprehensively introduce the molecular structure of CEP and its derivatives, describe in detail the pharmacological mechanisms of CEP in various diseases, and discuss how to chemically modify and design CEP to improve its bioavailability. In summary, this work will provide a reference for further research and clinical application of CEP.

A mechanistic updated overview on Cepharanthine as potential anticancer agent

The antitumor effects of traditional drugs have received increasing attention and active antitumor components extracted from traditional drugs have shown good efficacy with minimal adverse events. Cepharanthine(CEP for short) is an active component derived from the Stephania plants of Menispermaceae, which can regulate multiple signaling pathways alone or in combination with other therapeutic drugs to inhibit tumor cell proliferation, induce apoptosis, regulate autophagy, and inhibit angiogenesis, thereby inhibiting tumor progression. Therefore, we retrieved studies concerning CEP's antitumor effects in recent years and summarized the antitumor mechanism and targets, in order to gain new insights and establish a theoretical basis for further development and application of CEP.

Network and pathway-based analysis of genes associated with esophageal squamous cell carcinoma

Background

Although diagnostic methods and treatments have improved over the last few years, the 5-year survival rate of esophageal squamous cell carcinoma (ESCC) patients remains generally poor. The development of high-throughput technology has facilitated great achievements in localization of ESCC-related genes. To take a further step toward a thorough understanding of ESCC at a molecular level, the potential pathogenesis of ESCC needs to be deciphered.

Methods

The interaction of ESCC-related genes was explored by collecting genes associated with ESCC and then performing gene enrichment assays, pathway enrichment assays, pathway crosstalk analysis, and extraction of ESCC-specific subnetwork to describe the relevant biochemical processes.

Results

Through Gene Ontology (GO) enrichment analysis, many molecular functions related to response to chemical, cellular response to stimulus, and cell proliferation were found to be significantly enriched in ESCC-related genes. The results of pathway and pathway crosstalk analysis showed that pathways associated with multiple malignant tumors, the immune system, and metabolic processes were significantly enriched in ESCC-related genes. Through the analysis of specific subnetworks, we obtained some novel ESCC-related potential genes, such as MUC13, GSTO1, FIN, GRB2, CDC25C, and others.

Conclusions

The molecular mechanism of ESCC is extremely complex. Some inducing factors change the expression status of many genes. The abnormal expression of genes mediates the biological processes involved in immunity and metabolism, apoptosis, and cell proliferation, leading to the occurrence of tumors. The genes MUC13, RYK, and FIN may be potential prognostic indicators of ESCC; GRB2 and CDC25C may be potential targets of ESCC in proliferation. Our work may provide valuable information for further understanding the molecular mechanisms for the development of ESCC.

Cepharanthine hydrochloride inhibits the Wnt/β‑catenin/Hedgehog signaling axis in liver cancer

Cepharanthine, a biscoclaurine alkaloid isolated from the roots of Stephania cephalantha Hayata, has been reported to demonstrate antitumor activity across multiple cancer types; however, the mechanisms are still under investigation. High transcriptional responses by both the Hedgehog and Wnt pathways are frequently associated with specific human cancers, including liver cancer. To investigate whether these signaling pathways are involved in the pharmaceutical action of cepharanthine, we investigated Hedgehog and Wnt signaling in models of liver cancer treated with a semi‑synthetic cepharanthine derivative, cepharanthine hydrochloride (CH), in vitro and in vivo. By using MTT cytotoxic, scratch, Transwell, colony formation and flow cytometry assays, the pharmaceutical effect of CH was assessed. The compound was found to inhibit cellular proliferation and invasion, and promote apoptosis. Subsequent mechanistic investigations revealed that CH suppressed the Hedgehog/Gli1 signaling pathway by inhibiting Gli1 transcription and its transcriptional activity. CH also inhibited Wnt/β‑catenin signaling, and the pathway was found to be an upstream regulator of Hedgehog signaling in CH‑treated liver cancer cells. Finally, the antitumor effects of CH were demonstrated in an in vivo xenograft tumor model. Immunohistochemical analysis indicated that Gli1 protein levels were diminished in CH‑treated xenografts, compared with that noted in the controls. In summary, our results highlight a novel pharmaceutical antitumor mechanism of cepharanthine and provide support for CH as a clinical therapy for refractory liver cancer and other Wnt/Hedgehog‑driven cancers.

Targeting MUC1-C reverses the cisplatin resistance of esophageal squamous cell carcinoma in vitro and in vivo

BACKGROUND

The efficacy of chemotherapeutic treatment of esophageal squamous cell carcinoma (ESCC) is limited by drug resistance during. This severely compromises the long-term survival rate of patients. Therefore, reversing chemotherapy resistance in ESCC may improve the therapeutic outcome. Here, we investigated the molecular mechanism of MUC1-C, the C-terminal transmembrane subunit of MUC1 (a transmembrane heterodimer protein), and its role in the reversal of cisplatin sensitivity in ESCC cells.

METHODS

We assessed the efficacy of GO-203, a cell-penetrating peptide, as a chemotherapeutic target of MUC1-C using cell proliferation, colony-forming, and transwell assays. Apoptosis was analyzed in GO-203-treated cells by flow cytometry. Tumor xenograft assay was performed in nude mice to corroborate our in vitro findings.

RESULTS

GO-203 treatment inhibited cell proliferation and restrained the migration and invasion of cisplatin-resistant ESCC. Moreover, targeting MUC1 resulted in enhanced apoptosis in GO-203-treated cells. These in vitro pro-apoptotic and anti-proliferative effects of GO-203 in combination with cisplatin were validated by in vivo models. Significantly smaller tumor volumes were observed in ESCCs-xenografted nude mice treated with GO-203 in combination with cisplatin compared with mice treated with monotherapy or their control counterparts. We found that blocking MUC1-C with GO-203 significantly reversed the cisplatin resistance in ESCC via modulating Akt and ERK pathways.

CONCLUSIONS

Our findings suggest that GO-203 may hold potential as an ancillary therapeutic molecule and a chemosensitizer to improve the outcomes of cisplatin-based chemotherapy especially in patients with cisplatin-resistant ESCC.

Novel inhibitor of OCT1 enhances the sensitivity of human esophageal squamous cell carcinoma cells to antitumor agents

Esophageal squamous cell carcinoma (ESCC) is one of the most fatal malignancies of the digestive system, and shows an especially high incidence in some regions of China. Octamer transcription factors are a family of transcription factors whose DNA-binding domain is a POU domain. OCT transcription factors (OCT-TFs) mediate maintenance of the pluripotency of embryonic stem cells. We measured expression of OCT-TFs in ESCC clinical specimens. Among the OCTs tested, OCT1 showed the highest expression in ESCC tissues. Using molecular docking, we discovered a small-molecule inhibitor, which we named "novel inhibitor of OCT1" (NIO-1), for OCT1. Treatment with NIO-1 inhibited recruitment of OCT1 to the promoter region of its downstream genes and, consequently, repressed OCT1 activation. Treatment with NIO-1 enhanced the susceptibility of ESCC cells to chemotherapeutic agents. Therefore, OCT1 may be a valuable target for ESCC treatment, and NIO-1 could be a promising therapeutic agent.

Cepharanthine Regulates Autophagy via Activating the p38 Signaling Pathway in Lung Adenocarcinoma Cells

BACKGROUND

Cepharanthine (CEP) is an alkaloid extracted from Stephania cepharantha Hayata. This compound has been reported as a promising anti-tumor drug, although its potential molecular mechanism is not fully understood. Here, we studied the anti-tumor effect of CEP on human lung cancer cells and evaluated its molecular mechanism.

METHODS

The A549 cells were treated with CEP, the cell viability was measured by 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay, and formation of autophagosome was observed by acridine orange staining under a fluorescence microscope. The cell migration and invasion were determined by wound healing and transwell assay. The protein levels of autophagy-associated molecules, light chain 3 (LC3)、p38、and phospho-p38 in A549 cells, were determined by western blot analysis.

RESULT

The results showed that CEP inhibited cell proliferation, migration and invasion in A549 cells. Moreover, we found that CEP resulted in significant increases in levels of the autophagy marker protein LC3 in A549 cells. The number of intracellular acid dye follicular bright red fluorescence in A549 cells was significantly increased after CEP treatment. At the molecular levels, CEP markedly increased the phosphorylation of p38 in A549 cells. The knockdown of p38 expression by siRNA-p38 impaired the autophagy-regulating effect of CEP. Our results indicated that CEP-regulated autophagy was an anti-tumor effect and not a protective response to CEP.

CONCLUSION

Taken together, these results demonstrated that CEP regulated autophagy by activating the p38 signaling pathway, which could be provided a potential application for preventing lung cancer.

Hypothesis of using albumin to improve drug efficacy in cancers accompanied by hypoalbuminemia

A common problem in many cancers is the resistance of some patients to common drugs or relapse. Hypoalbuminemia has been reported in some of resistant cancer patients.This article evaluates the usefulness of albumin in the treatment of drug-resistant cancers with hypoalbuminemia based on available evidences.Rapid metabolism and drug excretion from the body is one of the causes of drug resistance. Albumin is the major plasma protein to which almost all drugs are bound. There is some evidence that increasing drug binding to albumin has beneficial effects on drug efficacy in some cancers and cancer cells. On the other hand, some reports have shown that cancer cells can use albumin as the energy and amino acid source.We have hypothesized that in this particular group of cancers, adding albumin to a treatment regimen could have a beneficial effect on drug efficacy and dosage. In fact, excess albumin can prevent rapid metabolism of drug by increasing the fraction of albumin-bound drug, and can increase drug delivery to cancer cells due to the absorption of drug-albumin complex by cancer cells.

miRNAs Modulate the Dichotomy of Cisplatin Resistance or Sensitivity in Breast Cancer: An Update of Therapeutic Implications

Cisplatin has a broad-spectrum antitumor activity and is widely used for the treatment of various malignant tumors. However, acquired or intrinsic resistance of cisplatin is a major problem for patients during the therapy. Recently, it has been reported Cancer Stem Cell (CSC)-derived drug resistance is a great challenge of tumor development and recurrence; therefore, the sensitivity of Breast Cancer Stem Cells (BCSCs) to cisplatin is of particular importance. Increasing evidence has shown that there is a relationship between cisplatin resistance/sensitivity genes and related miRNAs. It is known that dysregulation of relevant miRNAs plays a critical role in regulating target genes of cisplatin resistance/sensitivity in various pathways such as cellular uptake/efflux, Epithelial-Mesenchymal Transition (EMT), hypoxia, and apoptosis. Furthermore, the efficacy of the current chemotherapeutic drugs, including cisplatin, for providing personalized medicine, can be improved by controlling the expression of miRNAs. Thus, potential targeting of miRNAs can lead to miRNA-based therapies, which will help overcome drug resistance and develop more effective personalized anti-cancer and cotreatment strategies in breast cancer. In this review, we summarized the general understandings of miRNAregulated biological processes in breast cancer, particularly focused on the role of miRNA in cisplatin resistance/ sensitivity.

Thirteen bisbenzylisoquinoline alkaloids in five Chinese medicinal plants: Botany, traditional uses, phytochemistry, pharmacokinetic and toxicity studies

RELEVANCE

Bisbenzylisoquinoline (BBIQ) alkaloids are generally present in plants of Berberidaceae, Monimiaceae and Ranunculaceae families in tropical and subtropical regions. Some species of these families are used in traditional Chinese medicine, with the effects of clearing away heat and detoxification, promoting dampness and defecation, and eliminating sores and swelling. This article offers essential data focusing on 13 representative BBIQ compounds, which are mainly extracted from five plants. The respective botany, traditional uses, phytochemistry, pharmacokinetics, and toxicity are summarized comprehensively. In addition, the ADME prediction of the 13 BBIQ alkaloids is compared and analyzed with the data obtained.

MATERIALS AND METHODS

We have conducted a systematic review of the botanical characteristics, traditional uses, phytochemistry, pharmacokinetics and toxicity of BBIQ alkaloids based on literatures collected from PubMed, Web of Science and Elsevier during 1999-2020. ACD/Percepta software was utilized to predict the pharmacokinetic parameters of BBIQ alkaloids and their affinity with enzymes and transporters.

RESULTS

Botany, traditional uses, phytochemistry, pharmacokinetic and toxicity of 13 alkaloids, namely, tetrandrine, dauricine, curine, trilobine, isotrilobine, cepharanthine, daurisoline, thalicarpine, thalidasine, isotetrandrine, liensinine, neferine and isoliensinine, have been summarized in this paper. It can't be denied that these alkaloids are important material basis of pharmacological effects of family Menispermaceae and others, and for traditional and local uses which has been basically reproduced in the current studies. The 13 BBIQ alkaloids in this paper showed strong affinity and inhibitory effect on P-glycoprotein (P-gp), with poor oral absorption and potent binding ability with plasma protein. BBIQ alkaloids represented by tetrandrine play a key role in regulating P-gp or reversing multidrug resistance (MDR) in a variety of tumors. The irrationality of their usage could pose a risk of poisoning in vivo, including renal and liver toxicity, which are related to the formation of quinone methide during metabolism.

CONCLUSION

Although there is no further clinical evaluation of BBIQ alkaloids as MDR reversal agents, their effects on P-gp should not be ignored. Considering their diverse distribution, pharmacokinetic characteristics and toxicity reported during clinical therapy, the quality standards in different plant species and the drug dosage remain unresolved problems.

Traditional Herbal Medicine Mediated Regulations during Head and Neck Carcinogenesis

Head and neck squamous cell carcinoma (HNSCC) is one of the most prevalent neoplasms worldwide. It is well recognized that environmental challenges such as smoking, viral infection and alcohol consumption are key factors underlying HNSCC pathogenesis. Other than major clinical interventions (e.g., surgical resection, chemical and radiotherapy) that have been routinely practiced over years, adjuvant anticancer agents from Traditional Herbal Medicine (THM) are proposed, either alone or together with conventional therapies, to be experimentally effective for improving treatment efficacy in different cancers including HNSCCs. At a cellular and molecular basis, THM extracts could modulate different malignant indices via distinct signaling pathways and provide better control in HNSCC malignancy and its clinical complications such as radiotherapy-induced xerostomia/oral mucositis. In this article, we aim to systemically review the impacts of THM in regulating HNSCC tumorous identities and its potential perspective for clinical use.

Identification of Differentially Expressed Genes and miRNAs Associated with Esophageal Squamous Cell Carcinoma by Integrated Analysis of Microarray Data

To identify candidate key genes and miRNAs associated with esophageal squamous cell carcinoma (ESCC) development and prognosis, the gene expression profiles and miRNA microarray data including GSE20347, GSE38129, GSE23400, and GSE55856 were downloaded from the Gene Expression Omnibus (GEO) database. Clinical and survival data were retrieved from The Cancer Genome Atlas (TCGA). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of differentially expressed genes (DEGs) was analyzed via DAVID, while the DEG-associated protein-protein interaction network (PPI) was constructed using the STRING database. Additionally, the miRNA target gene regulatory network and miRNA coregulatory network were constructed, using the Cytoscape software. Survival analysis and prognostic model construction were performed via the survival (version 2.42-6) and rbsurv R packages, respectively. The results showed a total of 2575, 2111, and 1205 DEGs, and 226 differentially expressed miRNAs (DEMs) were identified. Pathway enrichment analyses revealed that DEGs were mainly enriched in 36 pathways, such as the proteasome, p53, and beta-alanine metabolism pathways. Furthermore, 448 nodes and 1144 interactions were identified in the PPI network, with MYC having the highest random walk score. In addition, 7 DEMs in the microarray data, including miR-196a, miR-21, miR-205, miR-194, miR-103, miR-223, and miR-375, were found in the regulatory network. Moreover, several reported disease-related miRNAs, including miR-198a, miR-103, miR-223, miR-21, miR-194, and miR-375, were found to have common target genes with other DEMs. Survival analysis revealed that 85 DEMs were related to prognosis, among which hsa-miR-1248, hsa-miR-1291, hsa-miR-421, and hsa-miR-7-5p were used for a prognostic survival model. Taken together, this study revealed the important roles of DEGs and DEMs in ESCC development, as well as DEMs in the prognosis of ESCC. This will provide potential therapeutic targets and prognostic predictors for ESCC.

The role of microRNA in cisplatin resistance or sensitivity

INTRODUCTION

Cisplatin is a chemotherapy drug that has been used to treat a number of cancers for decades, and is still one of the most commonly used anti-cancer agents. However, some patients do not respond to cisplatin while other patients who were originally sensitive to cisplatin eventually develop chemoresistance, leading to treatment failure or/and tumor recurrence.

AREAS COVERED

Different mechanisms contribute to cisplatin resistance or sensitivity, involving multiple pathways or/and processes such as DNA repair, DNA damage response, drug transport, and apoptosis. Among the various mechanisms, it appears that microRNAs play an important role in determining the resistance or sensitivity. In this article, we analyzed and summarized recent findings in this area, with the aim that these data can aid further research and understanding, leading to the eventual reduction of cisplatin resistance.

EXPERT COMMENTARY

microRNAs can positively or negatively regulate cisplatin resistance by acting on molecules or/and pathways related to apoptosis, autophagy, hypoxia, cancer stem cells, NF-κB, and Notch1. It appears that the modulation of relevant microRNAs can effectively re-sensitize cancer cells to cisplatin regimen in certain types of cancers including breast, colorectal, gastric, liver, lung, ovarian, prostate, testicular, and thyroid cancers.

Cepharanthine hydrochloride induces mitophagy targeting GPR30 in hepatocellular carcinoma (HCC)

Objectives: Cepharanthine exhibits a wide range of therapeutic effects against numerous cancers by virtue of its pleiotropic mechanisms. However, cepharanthine monotherapy has insufficient drug efficacy for cancers in animal models and clinical trials. The mechanism of its limited efficacy is unknown.Methods: We investigated the possible mechanism for the limited drug efficacy of cepharanthine in cancer therapy using both hepatocellular carcinoma (HCC) primary cells and cell lines, in vitro and in mouse xenograft models.Results: We found that cepharanthine hydrochloride (CH), a semi-synthetic derivative of cepharanthine, induced mitophagy independent of mTOR signaling, and played an AMPK-dependent protective role in the cell fate of HCC in vitro and in vivo. Mechanistically, we demonstrated that CH may bind to GPR30 receptor to activate the subsequent signal cascade involving mitochondrial fission, thus facilitating mitophagy. Therefore, we proposed a new therapeutic regimen for HCC involving CH combined with an autophagy inhibitor. This regimen exhibited remarkable anti-cancer effects in HCC xenograft mouse model.Conclusion: These results identify CH as a new mitophagy inducer targeting GPR30 receptor. The combination therapy of CH and an autophagy inhibitor may become a novel strategy for enhancing the anti-tumor potential of cepharanthine in HCC.

Naturally occurring anti-cancer compounds: shining from Chinese herbal medicine

Numerous natural products originated from Chinese herbal medicine exhibit anti-cancer activities, including anti-proliferative, pro-apoptotic, anti-metastatic, anti-angiogenic effects, as well as regulate autophagy, reverse multidrug resistance, balance immunity, and enhance chemotherapy in vitro and in vivo. To provide new insights into the critical path ahead, we systemically reviewed the most recent advances (reported since 2011) on the key compounds with anti-cancer effects derived from Chinese herbal medicine (curcumin, epigallocatechin gallate, berberine, artemisinin, ginsenoside Rg3, ursolic acid, silibinin, emodin, triptolide, cucurbitacin B, tanshinone I, oridonin, shikonin, gambogic acid, artesunate, wogonin, β-elemene, and cepharanthine) in scientific databases (PubMed, Web of Science, Medline, Scopus, and Clinical Trials). With a broader perspective, we focused on their recently discovered and/or investigated pharmacological effects, novel mechanism of action, relevant clinical studies, and their innovative applications in combined therapy and immunomodulation. In addition, the present review has extended to describe other promising compounds including dihydroartemisinin, ginsenoside Rh2, compound K, cucurbitacins D, E, I, tanshinone IIA and cryptotanshinone in view of their potentials in cancer therapy. Up to now, the evidence about the immunomodulatory effects and clinical trials of natural anti-cancer compounds from Chinese herbal medicine is very limited, and further research is needed to monitor their immunoregulatory effects and explore their mechanisms of action as modulators of immune checkpoints.

Cepharanthine: An update of its mode of action, pharmacological properties and medical applications

BACKGROUND

Cepharanthine (CEP) is a drug used in Japan since the 1950s to treat a number of acute and chronic diseases, including treatment of leukopenia, snake bites, xerostomia and alopecia. It is the only approved drug for Human use in the large class of bisbenzylisoquinoline alkaloids. This natural product, mainly isolated from the plant Stephania cephalantha Hayata, exhibits multiple pharmacological properties including anti-oxidative, anti-inflammatory, immuno-regulatory, anti-cancer, anti-viral and anti-parasitic properties.

PURPOSE

The mechanism of action of CEP is multifactorial. The drug exerts membrane effects (modulation of efflux pumps, membrane rigidification) as well as different intracellular and nuclear effects. CEP interferes with several metabolic axes, primarily with the AMP-activated protein kinase (AMPK) and NFκB signaling pathways. In particular, the anti-inflammatory effects of CEP rely on AMPK activation and NFκB inhibition.

CONCLUSION

In this review, the historical discovery and development of CEP are retraced, and the key mediators involved in its mode of action are presented. The past, present, and future of CEP are recapitulated. This review also suggests new opportunities to extend the clinical applications of this well-tolerated old Japanese drug.

Piperine: role in prevention and progression of cancer

Cancer is among the leading causes of death worldwide. Several pharmacological protocols have been developed in order to block tumor progression often showing partial efficacy and severe counterproductive effects. It is now conceived that a healthy lifestyle coupled with the consumption of certain phytochemicals can play a protective role against tumor development and progression. According to this vision, it has been introduced the concept of "chemoprevention". This term refers to natural agents with the capability to interfere with the tumorigenesis and metastasis, or at least, attenuate the cancer-related symptoms. Piperine (1-Piperoylpiperidine), a main extract of Piper longum and Piper nigrum, is an alkaloid with a long history of medicinal use. In fact, it exhibits a variety of biochemical and pharmaceutical properties, including chemopreventive activities without significant cytotoxic effects on normal cells, at least at doses < of 250 µg/ml. The aim of this review is to discuss the relevant molecular and cellular mechanisms underlying the chemopreventive action of this natural alkaloid.

Cepharanthine Hydrochloride Improves Cisplatin Chemotherapy and Enhances Immunity by Regulating Intestinal Microbes in Mice

Chemotherapy is one of the major treatment strategies for esophageal squamous cell carcinoma (ESCC). Unfortunately, most chemotherapeutic drugs have significant impacts on the intestinal microbes, resulting in side effects and reduced efficiency. Therefore, new strategies capable of overcoming these disadvantages of current chemotherapies are in urgent need. The natural product, Cepharanthine hydrochloride (CEH), is known for its anticancer and immunoregulatory properties. By sequencing the V4 region of 16S rDNA, we characterized the microbes of tumor-bearing mice treated with different chemotherapy strategies, including with CEH. We found that CEH improved the therapeutic effect of CDDP by manipulating the gut microbiota. Through metagenomic analyses of the microbes community, we identified a severe compositional and functional imbalance in the gut microbes community after CDDP treatment. However, CEH improved the effect of chemotherapy and ameliorated CDDP treatment-induced imbalance in the intestinal microbes. Mechanically, CEH activated TLR4 and MYD88 innate immune signaling, which is advantageous for the activation of the host's innate immunity to exert a balanced intestinal environment as well as to trigger a better chemotherapeutic response to esophageal cancer. In addition, TNFR death receptors were activated to induce apoptosis. In summary, our findings suggest that chemotherapy of CDDP combined with CEH increased the effect of chemotherapy and reduced the side effects on the microbes and intestinal mucosal immunity. We believe that these findings provide a theoretical basis for new clinical treatment strategies.

Upregulation of MDR- and EMT-Related Molecules in Cisplatin-Resistant Human Oral Squamous Cell Carcinoma Cell Lines

Cisplatin is one of the major drugs used in oral cancer treatments, but its usage can be limited by acquired drug resistance. In this study, we established three cisplatin-resistant oral squamous cell carcinoma (OSCC) cell lines and characterized them using cell viability assays, qPCR, Western blotting, FACS, immunofluorescence, and wound healing assays. Three OSCC cell lines (YD-8, YD-9, and YD-38) underwent long-term exposure to cisplatin, eventually acquiring resistance to the drug, which was confirmed by an MTT assay. In these three newly established cell lines (YD-8/CIS, YD-9/CIS, and YD-38/CIS), overexpression of multidrug resistance (MDR)-related genes was detected by qPCR and Western blotting. The cell lines displayed an increase in the functional activities of breast cancer resistance protein (BCRP) and multidrug resistance protein1 (MDR1) by rhodamine 123 and bodipy FL prazosin accumulation assays. Moreover, the cisplatin-resistant cells underwent morphological changes, from round to spindle-shaped, increased expression of epithelial-to-mesenchymal transition (EMT)-related molecules such as N-cadherin, and showed increased cell migration when compared with the parental cell lines. These results suggest that these newly established cell lines have acquired drug resistance and EMT induction.

Phytochemicals: Current strategy to sensitize cancer cells to cisplatin

Cisplatin-based chemotherapeutic regimens are the most frequently used adjuvant treatments for many types of cancer. However, the development of chemoresistance to cisplatin results in treatment failure. Despite the significant developments in understanding the mechanisms of cisplatin resistance, effective strategies to enhance the chemosensitivity of cisplatin are lacking. Phytochemicals are naturally occurring plant-based compounds that can augment the anti-cancer activity of cisplatin, with minimal side effects. Notably, some novel phytochemicals, such as curcumin, not only increase the efficacy of cisplatin but also decrease toxicity induced by cisplatin. However, the exact mechanisms underlying this process remain unclear. In this review, we discussed the progress made in utilizing phytochemicals to enhance the anti-cancer efficacy of cisplatin. We also presented some ideal phytochemicals as novel agents for counteracting cisplatin-induced organ damage.