The roles of cancer stem cell-derived secretory factors in shaping the immunosuppressive tumor microenvironment in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies worldwide and has a poor prognosis. Although immune checkpoint inhibitors have entered a new era of HCC treatment, their response rates are modest, which can be attributed to the immunosuppressive tumor microenvironment within HCC tumors. Accumulating evidence has shown that tumor growth is fueled by cancer stem cells (CSCs), which contribute to therapeutic resistance to the above treatments. Given that CSCs can regulate cellular and physical factors within the tumor niche by secreting various soluble factors in a paracrine manner, there have been increasing efforts toward understanding the roles of CSC-derived secretory factors in creating an immunosuppressive tumor microenvironment. In this review, we provide an update on how these secretory factors, including growth factors, cytokines, chemokines, and exosomes, contribute to the immunosuppressive TME, which leads to immune resistance. In addition, we present current therapeutic strategies targeting CSC-derived secretory factors and describe future perspectives. In summary, a better understanding of CSC biology in the TME provides a rational therapeutic basis for combination therapy with ICIs for effective HCC treatment.

Targeting AXL induces tumor-intrinsic immunogenic response in tyrosine kinase inhibitor-resistant liver cancer.

Hepatocellular carcinoma (HCC) is an aggressive malignancy without effective therapeutic approaches. Here, we evaluate the tumor-intrinsic mechanisms that attenuate the efficacy of immune checkpoint inhibitor (ICI) that is observed in patients with advanced HCC who progress on first-line tyrosine kinase inhibitor (TKI) therapy. Upregulation of AXL observed in sorafenib- and lenvatinib-resistant HCCs is correlated with poor response towards TKI and ICI treatments. AXL upregulation protects sorafenib-resistant HCC cells from oxidative stress, mitochondrial damage, and accompanying immunogenic cell death through suppressed tumor necrosis factor-α (TNF-α) and STING-type I interferon pathways. Pharmacological inhibition of AXL abrogates the protective effect and re-sensitizes TKI-resistant HCC tumors to anti-PD-1 treatment. We suggest that targeting AXL in combination with anti-PD-1 may provide an alternative treatment scheme for HCC patients who progress on TKI treatment.

CRISPR/Cas9 screens unravel miR-3689a-3p regulating sorafenib resistance in hepatocellular carcinoma via suppressing CCS/SOD1-dependent mitochondrial oxidative stress.

AIMS: Therapeutic outcome of sorafenib in hepatocellular carcinoma (HCC) is undermined by the development of drug resistance. This study aimed to identify the critical microRNA (miRNA) which is responsible for sorafenib resistance at the genomic level. METHODS: CRISPR/Cas9 screen followed by gain- and loss-of-function assays both in vitro and in vivo were applied to identify the role of miR-3689a-3p in mediating sorafenib response in HCC. The upstream and downstream molecules of miR-3689a-3p and their mechanism of action were investigated. RESULTS: CRISPR/Cas9 screening identified miR-3689a-3p was the most up-regulated miRNA in sorafenib sensitive HCC. Knockdown of miR-3689a-3p significantly increased sorafenib resistance, while its overexpression sensitized HCC response to sorafenib treatment. Proteomic analysis revealed that the effect of miR-3689a-3p was related to the copper-dependent mitochondrial superoxide dismutase type 1 (SOD1) activity. Mechanistically, miR-3689a-3p targeted the 3'UTR of the intracellular copper chaperone for superoxide dismutase (CCS) and suppressed its expression. As a result, miR-3689a-3p disrupted the intracellular copper trafficking and reduced SOD1-mediated scavenge of mitochondrial oxidative stress that eventually caused HCC cell death in response to sorafenib treatment. CCS overexpression blunted sorafenib response in HCC. Clinically, miR-3689a-3p was down-regulated in HCC and predicted favorable prognosis for HCC patients. CONCLUSION: Our findings provide comprehensive evidence for miR-3689a-3p as a positive regulator and potential druggable target for improving sorafenib treatment in HCC.

Broad-spectrum kinome profiling identifies CDK6 upregulation as a driver of lenvatinib resistance in hepatocellular carcinoma.

Increasing evidence has demonstrated that drug resistance can be acquired in cancer cells by kinase rewiring, which is an obstacle for efficient cancer therapy. However, it is technically challenging to measure the expression of protein kinases on large scale due to their dynamic range in human proteome. We employ a lysine-targeted sulfonyl fluoride probe, named XO44, which binds to 133 endogenous kinases in intact lenvatinib-resistant hepatocellular carcinoma (HCC) cells. This analysis reveals cyclin-dependent kinase 6 (CDK6) upregulation, which is mediated by ERK/YAP1 signaling cascade. Functional analyses show that CDK6 is crucial in regulation of acquired lenvatinib resistance in HCC via augmentation of liver cancer stem cells with clinical significance. We identify a noncanonical pathway of CDK6 in which it binds and regulates the activity of GSK3ß, leading to activation of Wnt/ß-catenin signaling. Consistently, CDK6 inhibition by palbociclib or degradation by proteolysis targeting chimeras (PROTACs) is highly synergistic with lenvatinib in vitro. Interestingly, palbociclib not only exerts maximal growth suppressive effect with lenvatinib in lenvatinib-resistant HCC models but also reshapes the tumor immune microenvironment. Together, we unveil CDK6 as a druggable target in lenvatinib-resistant HCC and highlight the use of a chemical biology approach to understand nongenetic resistance mechanisms in cancer.

Global trajectory and future prospects of metronomic chemotherapy research: A scientometric analysis (2000-2022).

This scientometric study aimed to provide a first comprehensive overview of the global research landscape of Metronomic Chemotherapy (MC) from 2000 to 2022 using a data-driven approach to identify key trends, collaborations, and potential opportunities. This study highlights the increasing prevalence of MC, with annual outputs increasing substantially over the same timeframe. The United States contributed the most to MC research, followed by Italy and China, while there was a lack of collaborative research efforts between countries and organizations. Through keyword co-occurrence analysis, we identified emerging interdisciplinary research areas, such as "nanoparticles," "immunotherapy," and "antitumor immunity." Our citation analysis identified the most influential authors, institutions, and journals, providing a comprehensive overview of the structure of knowledge and dissemination of MC research. Although the number of publications has decreased since 2019, the analysis indicates that this field has received substantial scholarly attention. These discoveries are extremely important for researchers, funding organizations, and policymakers because they highlight the need for more collaboration, interdisciplinary approaches, and resource allocation in underrepresented fields. This study concludes with recommendations for guiding future research and collaboration, resulting in a larger impact and fostering substantial advancements in MC research.

Protocol to track the biosynthesis of cholesterol in cultured HCC cells using 13C compound-specific stable isotopic tracers.

Cholesterol biosynthesis supports proliferation and drives resistance to tyrosine kinase inhibitor (TKI) therapy in hepatocellular carcinoma (HCC). Here, we present a protocol for using stable isotopic tracers to track the biosynthesis of cholesterol in cultured HCC cells. We describe steps for cell preparation, incubation, separation, and homogenization. We then detail lipid extraction and compound-specific isotope analysis for comparing and quantifying cholesterol synthesis between TKI-resistant HCC cells and their mock counterparts. This protocol can be expanded for use with other shorter-chained lipids.

Clathrin light chain A-enriched small extracellular vesicles remodel microvascular niche to induce hepatocellular carcinoma metastasis.

Small extracellular vesicles (sEVs) play a key role in exchanging cargoes between cells in tumour microenvironment. This study aimed to elucidate the functions and mechanisms of hepatocellular carcinoma (HCC) derived sEV-clathrin light chain A (CLTA) in remodelling microvascular niche. CLTA level in the circulating sEVs of HCC patients was analysed by enzyme-linked immunosorbent assay (ELISA). The functions of sEV-CLTA in affecting HCC cancerous properties were examined by multiple functional assays. Mass spectrometry was used to identify downstream effectors of sEV-CLTA in human umbilical vein endothelial cells (HUVECs). Tube formation, sprouting, trans-endothelial invasion and vascular leakiness assays were performed to determine the functions of sEV-CLTA and its effector, basigin (BSG) in HUVECs. BSG inhibitor, SP-8356, was tested in a mouse model of patient-derived xenografts (PDXs). Circulating sEVs of HCC patients had markedly enhanced CLTA levels than control individuals and were reduced in patients after surgery. HCC derived sEV-CLTA enhanced HCC cancerous properties, disrupted endothelial integrity and induced angiogenesis. Mechanistically, CLTA remodels microvascular niche by stabilizing and upregulating BSG. Last, SP-8356 alone or in combination with sorafenib attenuated PDXs growth. The study reveals the role of HCC derived sEV-CLTA in microvascular niche formation. Inhibition of CLTA and its mediated pathway may illuminate a new therapeutic strategy for HCC patients.

An autophagy-inducing stapled peptide induces mitochondria dysfunction and triggers autotic cell death in triple-negative breast cancer.

Autophagy is a lysosome-dependent bulk degradation process essential for cell viability but excessive autophagy leads to a unique form of cell death termed autosis. Triple-negative breast cancer (TNBC) is a highly aggressive subtype of breast cancer with notable defect in its autophagy process. In previous studies, we developed stapled peptides that specifically targeted the essential autophagy protein Beclin 1 to induce autophagy and promote endolysosomal trafficking. Here we show that one lead peptide Tat-SP4 induced mild increase of autophagy in TNBC cells but showed potent anti-proliferative effect that could not be rescued by inhibitors of programmed cell death pathways. The cell death induced by Tat-SP4 showed typical features of autosis including sustained adherence to the substrate surface, rupture of plasma membrane and effective rescue by digoxin, a cardioglycoside that blocks the Na+/K+ ATPase. Tat-SP4 also induced prominent mitochondria dysfunction including loss of mitochondria membrane potential, elevated mitochondria reactive oxygen species and reduced oxidative phosphorylation. The anti-proliferative effect of Tat-SP4 was confirmed in a TNBC xenograft model. Our study uncovers three notable aspects of autosis. Firstly, autosis can be triggered by moderate increase in autophagy if such increase exceeds the endogenous capacity of the host cells. Secondly, mitochondria may play an essential role in autosis with dysregulated autophagy leading to mitochondria dysfunction to trigger autosis. Lastly, intrinsic autophagy deficiency and quiescent mitochondria bioenergetic profile likely render TNBC cells particularly susceptible to autosis. Our designed peptides like Tat-SP4 may serve as potential therapeutic candidates against TNBC by targeting this vulnerability.

Identifying potential pharmacological targets and molecular pathways of Meliae cortex for COVID-19 therapy.

Coronavirus disease-19 (COVID-19), caused by SARS-CoV-2, has contributed to a significant increase in mortality. Proinflammatory cytokine-mediated cytokine release syndrome (CRS) contributes significantly to COVID-19. Meliae cortex has been reported for its several ethnomedical applications in the Chinese Pharmacopoeia. In combination with other traditional Chinese medicines (TCM), the Meliae cortex suppresses coronavirus. Due to its phytoconstituents and anti-inflammatory capabilities, we postulated that the Meliae cortex could be a potential therapeutic for treating COVID-19. The active phytonutrients, molecular targets, and pathways of the Meliae cortex have not been explored yet for COVID-19 therapy. We performed network pharmacology analysis to determine the active phytoconstituents, molecular targets, and pathways of the Meliae cortex for COVID-19 treatment. 15 active phytonutrients of the Meliae cortex and 451 their potential gene targets were retrieved from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) and SwissTargetPrediction website tool, respectively. 1745 COVID-19-related gene targets were recovered from the GeneCards. 104 intersection gene targets were determined by performing VENNY analysis. Using the DAVID tool, gene ontology (GO) and KEGG pathway enrichment analysis were performed on the intersection gene targets. Using the Cytoscape software, the PPI and MCODE analyses were carried out on the intersection gene targets, which resulted in 41 potential anti-COVID-19 core targets. Molecular docking was performed with AutoDock Vina. The 10 anti-COVID-19 core targets (AKT1, TNF, HSP90AA1, IL-6, mTOR, EGFR, CASP3, HIF1A, MAPK3, and MAPK1), three molecular pathways (the PI3K-Akt signaling pathway, the HIF-1 signaling pathway, and the pathways in cancer) and three active phytonutrients (4,8-dimethoxy-1-vinyl-beta-carboline, Trichilinin D, and Nimbolin B) were identified as molecular targets, molecular pathways, and key active phytonutrients of the Meliae cortex, respectively that significantly contribute to alleviating COVID-19. Molecular docking analysis further corroborated that three Meliae cortex's key active phytonutrients may ameliorate COVID-19 disease by modulating identified targets. Hence, this research offers a solid theoretic foundation for the future development of anti-COVID-19 therapeutics based on the phytonutrients of the Meliae cortex.

Cancer-Associated Fibroblasts in Hepatocellular Carcinoma and Cholangiocarcinoma.

Primary liver cancer (PLC) includes hepatocellular carcinoma and intrahepatic cholangiocarcinoma and is the sixth most common cancer worldwide with poor prognosis. PLC is characterized by an abundant stromal reaction in which cancer-associated fibroblasts (CAFs) are one of the major stromal components. Solid evidence has demonstrated the crucial role of CAFs in tumor progression, and CAF abundance is often correlated with poor clinical outcomes. Although CAFs are regarded as an attractive and promising target for PLC treatment, a poor understanding of CAF origins and heterogeneity and a lack of specific CAF markers are the major hurdles to efficient CAF-specific therapy. In this review, we examine recent advances in the understanding of CAF diversity in the context of biomarkers, subtypes, and functions in PLC. The regulatory roles of CAFs in extracellular matrix remodeling, metastasis, cancer stemness, and therapeutic resistance are summarized. With an increasing link between CAF abundance and reduced antitumor immune responses, we provide updated knowledge on the crosstalk between CAFs and immune cells within the tumor microenvironment, which leads to immune resistance. In addition, we present current CAF-targeted therapies and describe some future perspectives. A better understanding of CAF biology will shed light on a novel therapeutic strategy against PLC.

SCYL3, as a novel binding partner and regulator of ROCK2, promotes hepatocellular carcinoma progression.

Background & Aims: SCY1-like pseudokinase 3 (SCYL3) was identified as a binding partner of ezrin, implicating it in metastasis. However, the clinical relevance and functional role of SCYL3 in cancer remain uncharacterized. In this study, we aimed to elucidate the role of SCYL3 in the progression of hepatocellular carcinoma (HCC). Methods: The clinical significance of SCYL3 in HCC was evaluated in publicly available datasets and by qPCR analysis of an in-house HCC cohort. The functional significance and mechanistic consequences of SCYL3 were examined in SCYL3-knockdown/overexpressing HCC cells. In vivo tumor progression was evaluated in Tp53 KO/c-Myc OE mice using the sleeping beauty transposon system. Potential downstream pathways were investigated by co-immunoprecipitation, western blotting analysis and immunofluorescence staining. Results: SCYL3 is often overexpressed in HCC; it is preferentially expressed in metastatic human HCC tumors and is associated with worse patient survival. Suppression of SCYL3 in HCC cells attenuated cell proliferation and migration as well as in vivo metastasis. Intriguingly, endogenous SCYL3 overexpression increased tumor development and metastasis in Tp53 KO/c-Myc OE mice. Mechanistic investigations revealed that SCYL3 physically binds and regulates the stability and transactivating activity of ROCK2 (Rho kinase 2) via its C-terminal domain, leading to the increased formation of actin stress fibers and focal adhesions. Conclusions: These findings reveal that SCYL3 plays a critical role in promoting the progression of HCC and have implications for developing new therapeutic strategies to tackle metastatic HCC. Impact and implications: SCYL3 was first reported to be a binding partner of a metastasis-related gene, ezrin. To date, the clinical relevance and functional role of SCYL3 in cancer remain uncharacterized. Herein, we uncover its crucial role in liver cancer progression. We show that it physically binds and regulates the stability and transactivating activity of ROCK2 leading to HCC tumor progression. Our data provide mechanistic insight that SCYL3-mediated ROCK2 protein stability plays a pivotal role in growth and metastasis of HCC cells. Targeting SCYL3/ROCK2 signaling cascade may be a novel therapeutic strategy for treatment of HCC patients.

Wnt/ß-Catenin Signaling as a Driver of Stemness and Metabolic Reprogramming in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a major cause of cancer death worldwide due to its high rates of tumor recurrence and metastasis. Aberrant Wnt/ß-catenin signaling has been shown to play a significant role in HCC development, progression and clinical impact on tumor behavior. Accumulating evidence has revealed the critical involvement of Wnt/ß-catenin signaling in driving cancer stemness and metabolic reprogramming, which are regarded as emerging cancer hallmarks. In this review, we summarize the regulatory mechanism of Wnt/ß-catenin signaling and its role in HCC. Furthermore, we provide an update on the regulatory roles of Wnt/ß-catenin signaling in metabolic reprogramming, cancer stemness and drug resistance in HCC. We also provide an update on preclinical and clinical studies targeting Wnt/ß-catenin signaling alone or in combination with current therapies for effective cancer therapy. This review provides insights into the current opportunities and challenges of targeting this signaling pathway in HCC.

A special issue of Essays in Biochemistry on cancer stem cells.

Cancer stem cells (CSCs) are subpopulation of cells within the tumor bulk, which leads to tumor recurrence and therapeutic resistance. Identification of specific CSC targets for detection and efficient cancer therapy are the major hurdles in this research field. In this decade, basic researchers and clinicians made every effort to overcome these challenges to target CSCs using different approaches. This special issue includes a varied collection of review articles with comprehensive discussion on the complexity of CSC heterogeneity, signaling pathways regulating the behaviors of CSCs, the therapeutic resistance mechanism of CSCs, and therapeutic targets against CSCs. These review articles shed light on current advances in understanding of CSC biology.

Investigations of nitazoxanide molecular targets and pathways for the treatment of hepatocellular carcinoma using network pharmacology and molecular docking.

Nitazoxanide has been investigated for colorectal cancer and breast cancer. However, its molecular targets and pathways have not yet been explored for hepatocellular carcinoma (HCC) treatment. Utilizing a network pharmacology approach, nitazoxanide's potential targets and molecular pathways for HCC treatment were investigated. HCC targets were extracted from the GeneCards database. Potential targets of nitazoxanide were predicted using Swiss Target Prediction and Super Pred. Intersecting targets were analyzed with VENNY online tool. Using Cytoscape, a protein-protein interaction (PPI), cluster, and core targets-pathways networks were constructed. Using the Database for Annotation, Visualization and Integrated Discovery (DAVID), gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted. The nitazoxanide was molecularly docked with anti-HCC core targets by employing Auto Dock Vina. A total of 168 potential targets of nitazoxanide, 13,415 HCC-related targets, and 153 intersecting targets were identified. The top eight anti-HCC core targets were identified: SRC, EGFR, CASP3, MMP9, mTOR, HIF1A, ERBB2, and PPARG. GO enrichment analysis showed that nitazoxanide might have anti-HCC effects by affecting gene targets involved in multiple biological processes (BP) (protein phosphorylation, transmembrane receptor protein tyrosine kinase (RTKs) signaling pathway, positive regulation of MAP kinase activity, etc.). KEGG pathways and core targets-pathways network analysis indicated that pathways in cancer and proteoglycans in cancer are two key pathways that significantly contribute to the anti-HCC effects of nitazoxanide. Results of molecular docking demonstrated the potential for active interaction between the top eight anti-HCC core targets and nitazoxanide. Our research offers a theoretical basis for the notion that nitazoxanide may have distinct therapeutic effects in HCC, and the identified pharmacological targets and pathways might function as biomarkers for HCC therapy.

Network pharmacology and molecular docking-based investigations of Kochiae Fructus's active phytomolecules, molecular targets, and pathways in treating COVID-19.

COVID-19 disease is caused by SARS-CoV-2. Hyper-inflammation mediated by proinflammatory cytokines is humans' primary etiology of SARS-CoV-2 infection. Kochiae Fructus is widely used in China as traditional Chinese medicine (TCM) to treat inflammatory diseases. Due to its anti-inflammatory properties, we hypothesized that Kochiae Fructus would be a promising therapeutic agent for COVID-19. The active phytomolecules, targets, and molecular pathways of Kochiae Fructus in treating COVID-19 have not been explored yet. Network pharmacology analysis was performed to determine the active phytomolecules, molecular targets, and pathways of Kochiae Fructus. The phytomolecules in Kochiae Fructus were retrieved from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database, and their potential targets were predicted with the SwissTargetPrediction webserver. COVID-19-related targets were recovered from the GeneCards database. Intersecting targets were determined with the VENNY tool. The Protein-protein interaction (PPI) and Molecular Complex Detection (MCODE) network analyses were constructed using the Cytoscape software. Using the DAVID tool, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed on the intersecting targets. AutoDock Vina (version 1.2.0.) was used for molecular docking analysis. Six active phytomolecules and 165 their potential targets, 1,745 COVID-19-related targets, and 34 intersecting targets were identified. Network analysis determined 13 anti-COVID-19 core targets and three key active phytomolecules (Oleanolic acid, 9E,12Z-octadecadienoic acid, and 11,14-eicosadienoic acid). Three key pathways (pathways in cancer, the TNF signaling pathway, and lipid and atherosclerosis) and the top six anti-COVID-19 core targets (IL-6, PPARG, MAPK3, PTGS2, ICAM1, and MAPK1) were determined to be involved in the treatment of COVID-19 with active phytomolecules of Kochiae Fructus. Molecular docking analysis revealed that three key active phytomolecules of Kochiae Fructus had a regulatory effect on the identified anti-COVID-19 core targets. Hence, these findings offer a foundation for developing anti-COVID-19 drugs based on phytomolecules of Kochiae Fructus.

Caspase-3-Induced Activation of SREBP2 Drives Drug Resistance via Promotion of Cholesterol Biosynthesis in Hepatocellular Carcinoma.

Accumulating evidence has demonstrated that drug resistance can be acquired in cancer through the repopulation of tumors by cancer stem cell (CSC) expansion. Here, we investigated mechanisms driving resistance and CSC repopulation in hepatocellular carcinoma (HCC) as a cancer model using two drug-resistant, patient-derived tumor xenografts that mimicked the development of acquired resistance to sorafenib or lenvatinib treatment observed in patients with HCC. RNA sequencing analysis revealed that cholesterol biosynthesis was most commonly enriched in the drug-resistant xenografts. Comparison of the genetic profiles of CD133+ stem cells and CD133- bulk cells from liver regeneration and HCC mouse models showed that the cholesterol pathway was preferentially upregulated in liver CSCs compared with normal liver stem cells. Consistently, SREBP2-mediated cholesterol biosynthesis was crucial for the augmentation of liver CSCs, and loss of SREBP2 conferred sensitivity to tyrosine kinase inhibitors, suggesting a role in regulation of acquired drug resistance in HCC. Similarly, exogenous cholesterol-treated HCC cells showed enhanced cancer stemness abilities and drug resistance. Mechanistically, caspase-3 (CASP3) mediated cleavage of SREBP2 from the endoplasmic reticulum to promote cholesterol biosynthesis, which consequently caused resistance to sorafenib/lenvatinib treatment by driving activation of the sonic hedgehog signaling pathway. Simvastatin, an FDA-approved cholesterol-lowering drug, not only suppressed HCC tumor growth but also sensitized HCC cells to sorafenib. These findings demonstrate that CSC populations in HCC expand via CASP3-dependent, SREBP2-mediated cholesterol biosynthesis in response to tyrosine kinase inhibitor therapy and that targeting cholesterol biosynthesis can overcome acquired drug resistance. SIGNIFICANCE: This study finds that cholesterol biosynthesis supports the expansion of cancer stem cell populations to drive resistance to tyrosine kinase inhibitor therapy in hepatocellular carcinoma, identifying potential therapeutic approaches for improving cancer treatment.

Network-Pharmacology-Based Study on Active Phytochemicals and Molecular Mechanism of Cnidium monnieri in Treating Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a malignancy with a high mortality rate globally. For thousands of years, Cnidium monnieri has been used to treat human ailments and is regarded as a veritable treasure trove for drug discovery. This study has investigated the key active phytochemicals and molecular mechanisms of Cnidium monnieri implicated in curing HCC. We utilized the TCMSP database to collect data on the phytochemicals of Cnidium monnieri. The SwissTargetPrediction website tool was used to predict the targets of phytochemicals of Cnidium monnieri. HCC-related genes were retrieved from OncoDB.HCC and Liverome, two liver-cancer-related databases. Using the DAVID bioinformatic website tool, Gene Ontology (GO) and KEGG enrichment analysis were performed on the intersecting targets of HCC-related genes and active phytochemicals in Cnidium monnieri. A network of active phytochemicals and anti-HCC targets was constructed and analyzed using Cytoscape software. Molecular docking of key active phytochemicals was performed with anti-HCC targets using AutoDock Vina (version 1.2.0.). We identified 19 active phytochemicals in Cnidium monnieri, 532 potential targets of these phytochemicals, and 566 HCC-related genes. Results of GO enrichment indicated that Cnidium monnieri might be implicated in affecting gene targets involved in multiple biological processes, such as protein phosphorylation, negative regulation of the apoptotic process, which could be attributed to its anti-HCC effects. KEGG pathway analyses indicated that the PI3K-AKT signaling pathway, pathways in cancer, proteoglycans in cancer, the TNF signaling pathway, VEGF signaling pathway, ErbB signaling pathway, and EGFR tyrosine kinase inhibitor resistance are the main pathways implicated in the anti-HCC effects of Cnidium monnieri. Molecular docking analyses showed that key active phytochemicals of Cnidium monnieri, such as ar-curcumene, diosmetin, and (E)-2,3-bis(2-keto-7-methoxy-chromen-8-yl)acrolein, can bind to core therapeutic targets EGFR, CASP3, ESR1, MAPK3, CCND1, and ERBB2. The results of the present study offer clues for further investigation of the anti-HCC phytochemicals and mechanisms of Cnidium monnieri and provide a basis for developing modern anti-HCC drugs based on phytochemicals in Cnidium monnieri.

Targeting protein kinases in cancer stem cells.

Cancer stem cells (CSCs) are subpopulations of cancer cells within the tumor bulk that have emerged as an attractive therapeutic target for cancer therapy. Accumulating evidence has shown the critical involvement of protein kinase signaling pathways in driving tumor development, cancer relapse, metastasis, and therapeutic resistance. Given that protein kinases are druggable targets for cancer therapy, tremendous efforts are being made to target CSCs with kinase inhibitors. In this review, we summarize the current knowledge and overview of the roles of protein kinases in various signaling pathways in CSC regulation and drug resistance. Furthermore, we provide an update on the preclinical and clinical studies for the use of kinase inhibitors alone or in combination with current therapies for effective cancer therapy. Despite great premises for the use of kinase inhibitors against CSCs, further investigations are needed to evaluate their efficiencies without any adverse effects on normal stem cells.