Cordycepin suppresses integrin/FAK signaling and epithelial-mesenchymal transition in hepatocellular carcinoma

Integrins in human hepatocellular carcinoma tumorigenesis and therapy

ABSTRACT

Integrins are a family of transmembrane receptors that connect the extracellular matrix and actin skeleton, which mediate cell adhesion, migration, signal transduction, and gene transcription. As a bi-directional signaling molecule, integrins can modulate many aspects of tumorigenesis, including tumor growth, invasion, angiogenesis, metastasis, and therapeutic resistance. Therefore, integrins have a great potential as antitumor therapeutic targets. In this review, we summarize the recent reports of integrins in human hepatocellular carcinoma (HCC), focusing on the abnormal expression, activation, and signaling of integrins in cancer cells as well as their roles in other cells in the tumor microenvironment. We also discuss the regulation and functions of integrins in hepatitis B virus-related HCC. Finally, we update the clinical and preclinical studies of integrin-related drugs in the treatment of HCC.

Investigation of Anti-Liver Cancer Activity of the Herbal Drug FDY003 Using Network Pharmacology

Globally, liver cancer (LC) is the sixth-most frequently occurring and the second-most fatal malignancy, responsible for 0.83 million deaths annually. Although the application of herbal drugs in cancer therapies has increased, their anti-LC activity and relevant mechanisms have not been fully studied from a systems perspective. To address these issues, we conducted a system-perspective network pharmacological investigation into the activity and mechanisms underlying the action of the herbal drug. FDY003 reduced the viability of human LC treatment. FDY003 reduced the viability of human LC cells and elevated their chemosensitivity. There were a total of 16 potential bioactive chemical components in FDY003 and they had 91 corresponding targets responsible for the pathological processes in LC. These FDY003 targets were functionally involved in regulating the survival, proliferation, apoptosis, and cell cycle of LC cells. Additionally, we found that FDY003 may target key signaling cascades connected to diverse LC pathological mechanisms, namely, PI3K-Akt, focal adhesion, IL-17, FoxO, MAPK, and TNF pathways. Overall, this study contributed to integrative mechanistic insights into the anti-LC potential of FDY003.

How Should the Worldwide Knowledge of Traditional Cancer Healing Be Integrated with Herbs and Mushrooms into Modern Molecular Pharmacology?

Traditional herbal medicine (THM) is a “core” from which modern medicine has evolved over time. Besides this, one third of people worldwide have no access to modern medicine and rely only on traditional medicine. To date, drugs of plant origin, or their derivates (paclitaxel, vinblastine, vincristine, vinorelbine, etoposide, camptothecin, topotecan, irinotecan, and omacetaxine), are very important in the therapy of malignancies and they are included in most chemotherapeutic regimes. To date, 391,000 plant and 14,000 mushroom species exist. Their medical and biochemical capabilities have not been studied in detail. In this review, we systematized the information about plants and mushrooms, as well as their active compounds with antitumor properties. Plants and mushrooms are divided based on the regions where they are used in ethnomedicine to treat malignancies. The majority of their active compounds with antineoplastic properties and mechanisms of action are described. Furthermore, on the basis of the available information, we divided them into two priority groups for research and for their potential of use in antitumor therapy. As there are many prerequisites and some examples how THM helps and strengthens modern medicine, finally, we discuss the positive points of THM and the management required to transform and integrate THM into the modern medicine practice.

Cordycepin (3′-Deoxyadenosine) Suppresses Heat Shock Protein 90 Function and Targets Tumor Growth in an Adenosine Deaminase-Dependent Manner

Alterations in metabolism and energy production are increasingly being recognized as important drivers of neoplasia, raising the possibility that metabolic analogs could disrupt oncogenic pathways. 3′-deoxyadenosine, also known as cordycepin, is an adenosine analog that inhibits the growth of several types of cancer. However, the effects of cordycepin have only been examined in a limited number of tumor types, and its mechanism of action is poorly understood. We found that cordycepin slows the growth and promotes apoptosis in uveal melanoma, as well as a range of other hard-to-treat malignancies, including retinoblastoma, atypical teratoid rhabdoid tumors, and diffuse midline gliomas. Interestingly, these effects were dependent on low adenosine deaminase (ADA) expression or activity. Inhibition of ADA using either siRNA or pharmacologic approaches sensitized tumors with higher ADA to cordycepin in vitro and in vivo, with increased apoptosis, reduced clonogenic capacity, and slower migration of neoplastic cells. Our studies suggest that ADA is both a biomarker predicting response to cordycepin and a target for combination therapy. We also describe a novel mechanism of action for cordycepin: competition with adenosine triphosphate (ATP) in binding to Hsp90, resulting in impaired processing of oncogenic Hsp90 client proteins.

Cordycepin Inhibits Triple-Negative Breast Cancer Cell Migration and Invasion by Regulating EMT-TFs SLUG, TWIST1, SNAIL1, and ZEB1

Cancer metastasis is the most important cause of cancer-related death, and epithelial-to-mesenchymal transition (EMT) plays crucial roles in cancer metastasis. Cordycepin (CD) is highly enriched in the medicinally used Cordyceps mushroom. In this study, we conducted the antimetastatic activities of CD, specifically focusing on its regulatory effects on EMT-inducing transcription factors (EMT-TFs) in triple-negative breast cancer (TNBC). Our study showed CD to inhibit the growth, migration, and invasion of BT549 and 4T1 cancer cell lines, by employing cell viability assay and real-time cell analyses. The protein levels of N-Cadherin and E-Cadherin, as well as their transcription factors TWIST1, SLUG, SNAIL1, and ZEB1 in BT549 and 4T1 cells, were estimated by Western blot assays. Results from dual-luciferase reporter assays demonstrated that CD is capable of inactivating the EMT signaling pathway by inhibiting TWIST1 and SLUG expression. Furthermore, in vivo studies with mice carrying cancer cell-derived allograft tumors showed the inhibitory effect of CD on cancer cell growth and metastasis. Furthermore, the additive/synergistic anti-metastasis effect of CD and thymoquinone (TQ), another natural product with promising anticancer roles, was demonstrated by combinational treatment. The results from this research indicate that CD would be a promising therapeutic molecule against TNBC by targeting EMT-TFs, possibly in SLUG, TWIST1, SNAIL1, and ZEB1.

Aldehyde dehydrogenase 3B2 promotes the proliferation and invasion of cholangiocarcinoma by increasing Integrin Beta 1 expression

Aldehyde dehydrogenases (ALDHs) play an essential role in regulating malignant tumor progression; however, their role in cholangiocarcinoma (CCA) has not been elucidated. We analyzed the expression of ALDHs in 8 paired tumor and peritumor perihilar cholangiocarcinoma (pCCA) tissues and found that ALDH3B1 and ALDH3B2 were upregulated in tumor tissues. Further survival analysis in intrahepatic cholangiocarcinoma (iCCA, n = 27), pCCA (n = 87) and distal cholangiocarcinoma (dCCA, n = 80) cohorts have revealed that ALDH3B2 was a prognostic factor of CCA and was an independent prognostic factor of iCCA and pCCA. ALDH3B2 expression was associated with serum CEA in iCCA and dCCA, associated with tumor T stage, M stage, neural invasion and serum CA19-9 in pCCA. In two cholangiocarcinoma cell lines, overexpression of ALDH3B2 promoted cell proliferation and clone formation by promoting the G1/S phase transition. Knockdown of ALDH3B2 inhibited cell migration, invasion, and EMT in vitro, and restrained tumor metastasis in vivo. Patients with high expression of ALDH3B2 also have high expression of ITGB1 in iCCA, pCCA, and dCCA at both mRNA and protein levels. Knockdown of ALDH3B2 downregulated the expression of ITGB1 and inhibited the phosphorylation level of c-Jun, p38, and ERK. Meanwhile, knockdown of ITGB1 inhibited the promoting effect of ALDH3B2 overexpression on cell proliferation, migration, and invasion. ITGB1 is also a prognostic factor of iCCA, pCCA, and dCCA and double-positive expression of ITGB1 and ALDH3B2 exhibits better performance in predicting patient prognosis. In conclusion, ALDH3B2 promotes tumor proliferation and metastasis in CCA by regulating the expression of ITGB1 and upregulating its downstream signaling pathway. The double-positive expression of ITGB1 and ALDH3B2 serves as a better prognostic biomarker of CCA.

A Systematic Review of the Biological Effects of Cordycepin

We conducted a systematic review of the literature on the effects of cordycepin on cell survival and proliferation, inflammation, signal transduction and animal models. A total of 1204 publications on cordycepin were found by the cut-off date of 1 February 2021. After application of the exclusion criteria, 791 papers remained. These were read and data on the chosen subjects were extracted. We found 192 papers on the effects of cordycepin on cell survival and proliferation and calculated a median inhibitory concentration (IC50) of 135 µM. Cordycepin consistently repressed cell migration (26 papers) and cellular inflammation (53 papers). Evaluation of 76 papers on signal transduction indicated consistently reduced PI3K/mTOR/AKT and ERK signalling and activation of AMPK. In contrast, the effects of cordycepin on the p38 and Jun kinases were variable, as were the effects on cell cycle arrest (53 papers), suggesting these are cell-specific responses. The examination of 150 animal studies indicated that purified cordycepin has many potential therapeutic effects, including the reduction of tumour growth (37 papers), repression of pain and inflammation (9 papers), protecting brain function (11 papers), improvement of respiratory and cardiac conditions (8 and 19 papers) and amelioration of metabolic disorders (8 papers). Nearly all these data are consistent with cordycepin mediating its therapeutic effects through activating AMPK, inhibiting PI3K/mTOR/AKT and repressing the inflammatory response. We conclude that cordycepin has excellent potential as a lead for drug development, especially for age-related diseases. In addition, we discuss the remaining issues around the mechanism of action, toxicity and biodistribution of cordycepin.

Cordycepin attenuates high-fat diet-induced non-alcoholic fatty liver disease via down-regulation of lipid metabolism and inflammatory responses

Cordycepin (CRD), an adenosine analog derived from traditional Chinese medicine, is an active component in Cordyceps militaris. It has been shown to have many protective effects during liver injury and ameliorate liver disease progression, but little is known about its effect on non-alcoholic fatty liver disease (NAFLD). This study aims to explore the effects of CRD on obesity-induced NAFLD. In this experiment, C57BL/6 J mice were randomly assigned into normal control group (NC), high fat diet group (HFD) and HFD + CRD group for 8 weeks. The body weights were recorded weekly, at the end of the experiments, the liver and serum samples were collected. We found that CRD administration reduced body weight and decreased the weight of adipose and liver, and CRD relieved liver injure through diminishing of histopathological changes and decreasing serum levels of AST, ALT, TG, TC, LDL-C and increased the level of HDL-C. Furthermore, treatment with CRD significantly alleviated expression of inflammatory factors (TNF-α, IL-6 and Il-1β) and macrophage markers (MCP1, MIP2, mKC and VCAM1). On the other hand, compared with HFD group, the CRD treated group markedly down-regulated relative proteins of lipid anabolism (SREBP1-c, ACC, SCD-1, LXRα and CD36) and up-regulated relative proteins of β-oxidation (p-AMPK, AMPK, CPT-1 and PPARα). In summary, our results suggest that CRD can be a potential therapeutic agent in the prevention and treatment of NAFLD, which may be closely related to its effect on lipid metabolism and inflammatory responses.

Activity of Cordycepin From Cordyceps sinensis Against Drug-Resistant Tumor Cells as Determined by Gene Expression and Drug Sensitivity Profiling

Cordycepin is one of the substantial components of the parasitic fungus Cordyceps sinensis as well as other Cordyceps species. It exerts various effects such as antimetastatic, antiinflammatory, antioxidant, and neuroprotective activities. Assorted studies revealed in vitro and in vivo anticancer influence of cordycepin and put forward its potential for cancer therapy. However, the role of multidrug resistance-associated mechanisms for the antitumor effect of cordycepin has not been investigated in great detail thus far. Therefore, we searched cordycepin’s cytotoxicity with regard to well-known anticancer drug resistance mechanisms, including ABCB1, ABCB5, ABCC1, ABCG2, EGFR, and TP53, and identified putative molecular determinants related to the cellular responsiveness of cordycepin. Bioinformatic analyses of NCI microarray data and gene promoter transcription factor binding motif analyses were performed to specify the mechanisms of cordycepin towards cancer cells. COMPARE and hierarchical analyses led to the detection of the genes involved in cordycepin’s cytotoxicity and sensitivity and resistance of cell lines towards cordycepin. Tumor-type dependent response and cross-resistance profiles were further unravelled. We found transcription factors potentially involved in the common transcriptional regulation of the genes identified by COMPARE analyses. Cordycepin bypassed resistance mediated by the expression of ATP-binding cassete (ABC) transporters (P-gp, ABCB5, ABCC1 and BCRP) and mutant epidermal growth factor receptor (EGFR). The drug sensitivity profiles of several DNA Topo I and II inhibitors were significantly correlated with those of cordycepin’s activity. Among eight different tumor types, prostate cancer was the most sensitive, whereas renal carcinoma was the most resistant to cordycepin. NF-κB was discovered as a common transcription factor. The potential of cordycepin is set forth as a potential new drug lead by bioinformatic evaluations. Further experimental studies are warranted for better understanding of cordycepin’s activity against cancer.

Cordycepin-loaded Nanoparticles from Cassava Starch Promote the Proliferation of Submandibular Gland Cells and Inhibit the Growth of Oral Squamous Carcinoma Cells

This study examined associations between the effect of treatment with nano-cassava starch that contained cordycepin (CS) extract, targeting human submandibular gland cells (HSGs), and human oral squamous carcinoma cells (HSC-4). Cassava starch nanoparticles (CSNPs) were prepared by either physical or acid treatment. These nanoparticles were then loaded with either CS or cordyceps medium and then treated with HSG or HSC-4 cells in different concentrations of CS and nanoparticles. Moreover, the protein secretion, reactive oxygen species (ROS) activity and the expression of salivary-specific genes, antioxidant gene were determined after treatment. CSNPs can enhance the activity of CS at low concentrations. Cordycepin-loaded cassava starch nanoparticles (CCSNPs) increased HSG proliferation, protein secretion, and the expression of salivary-specific genes, AMY and AQP5. Besides, CCSNPs also protected and scavenged of ROS via the stimulation of the antioxidant genes in HSGs, indicating the protective roles of CS to HSGs. On the other hand, CCSNPs inhibited the growth of HSC-4 cells by stimulating ROS generation and reducing protein secretion. This finding suggested that CCSNPs presented the dual actions against HSGs and human oral squamous carcinoma cells, and the encapsulation of CS with cassava nanoparticles enhanced the activity of CS.

Crosstalk between Epidermal Growth Factor Receptors (EGFR) and integrins in resistance to EGFR tyrosine kinase inhibitors (TKIs) in solid tumors

Cell adhesion to the extracellular matrix (ECM) is important in a variety of physiological and pathologic processes, including development, tumor invasion, and metastasis. Integrin-mediated attachment to ECM proteins has emerged to cue events primitively important for the transformed phenotype of human cancer cells. Cross-talk between integrins and growth factor receptors takes an increasingly prominent role in defining adhesion, motility, and cell growth. This functional interaction has expanded beyond to link integrins with resistance to Tyrosine kinase inhibitors (TKIs) of Epidermal Growth Factor Receptors (EGFRs). In this regard, integrin-mediated adhesion has two separate functions one as a clear collaborator with growth factor receptor signaling and the second as a basic mechanism contributing in Epithelial to Mesenchymal Transition (EMT) which affects response to chemotherapy. This review provides an overview of these mechanisms and describes treatment options for selectively targeting and disrupting integrin interaction to EGFR for cancer therapy.

Cordycepin in Anticancer Research: Molecular Mechanism of Therapeutic Effects

Background:

Cordycepin is a nucleotide analogue from Cordyceps mushrooms, which occupies a notable place in traditional medicine.

Objective:

In this review article, we have discussed the recent findings on the molecular aspects of cordycepin interactions with its recognized cellular targets, and possible mechanisms of its anticancer activity.

Methods:

We have explored databases like pubmed, google scholar, scopus and web of science for the update information on cordycepin and mechanisms of its anticancer activity, and reviewed in this study.

Results:

Cordycepin has been widely recognized for its therapeutic potential against many types of cancers by various mechanisms. More specifically, cordycepin can induce apoptosis, resist cell cycle and cause DNA damage in cancer cells, and thus kill or control cancer cell growth. Also cordycepin can induce autophagy and modulate immune system. Furthermore, cordycepin also inhibits tumor metastasis. Although many success stories of cordycepin in anticancer research in vitro and in animal model, and there is no successful clinical trial yet.

Conclusion:

Ongoing research studies have reported highly potential anticancer activities of cordycepin with numerous molecular mechanisms. The in vitro and in vivo success of cordycepin in anticancer research might influence the clinical trials of cordycepin, and this molecule might be used for development of future cancer drug.

Reversal of Epithelial-Mesenchymal Transition by Natural Anti-Inflammatory and Pro-Resolving Lipids

Epithelial mesenchymal transition (EMT) is a key process in the progression of malignant cancer. Therefore, blocking the EMT can be a critical fast track for the development of anticancer drugs. In this paper, we update recent research output of EMT and we explore suppression of EMT by natural anti-inflammatory compounds and pro-resolving lipids.

Cordycepin Suppresses Endothelial Cell Proliferation, Migration, Angiogenesis, and Tumor Growth by Regulating Focal Adhesion Kinase and p53

Focal adhesion kinase (FAK) plays an important role in vascular development, including the regulation of endothelial cell (EC) adhesion, migration, proliferation, and survival. 3'-deoxyadenosine (cordycepin) is known to suppress FAK expression, cell migration, and the epithelial⁻mesenchymal transition in hepatocellular carcinoma (HCC). However, whether cordycepin affects FAK expression and cellular functions in ECs and the specific molecular mechanism remain unclear. In this study, we found that cordycepin suppressed FAK expression and the phosphorylation of FAK (p-FAK) at Tyr397 in ECs. Cordycepin inhibited the proliferation, wound healing, transwell migration, and tube formation of ECs. Confocal microscopy revealed that cordycepin significantly reduced FAK expression and decreased focal adhesion number of ECs. The suppressed expression of FAK was accompanied by induced p53 and p21 expression in ECs. Finally, we demonstrated that cordycepin suppressed angiogenesis in an in vivo angiogenesis assay and reduced HCC tumor growth in a xenograft nude mice model. Our study indicated that cordycepin could attenuate cell proliferation and migration and may result in the impairment of the angiogenesis process and tumor growth via downregulation of FAK and induction of p53 and p21 in ECs. Therefore, cordycepin may be used as a potential adjuvant for cancer therapy.

The Anticancer Properties of Cordycepin and Their Underlying Mechanisms

Cordyceps is a genus of ascomycete fungi that has been used for traditional herbal remedies. It contains various bioactive ingredients including cordycepin. Cordycepin, also known as 3-deoxyadenosine, is a major compound and has been suggested to have anticancer potential. The treatment of various cancer cells with cordycepin in effectively induces cell death and retards their cancerous properties. However, the underlying mechanism is not fully understood. Recent evidence has shed light on the molecular pathways involving cysteine-aspartic proteases (caspases), mitogen-activated protein kinases (MAPKs), and glycogen synthase kinase 3 beta (GSK-3β). Furthermore, the pathways are mediated by putative receptors, such as adenosine receptors (ADORAs), death receptors (DRs), and the epidermal growth factor receptor (EGFR). This review provides the molecular mechanisms by which cordycepin functions as a singular or combinational anticancer therapeutic agent.

PBN11-8, a Cytotoxic Polypeptide Purified from Marine Bacillus, Suppresses Invasion and Migration of Human Hepatocellular Carcinoma Cells by Targeting Focal Adhesion Kinase Pathways

The development of antitumor drugs has attracted cancer researchers and the identification of novel antitumor lead compounds is certainly of great interest. The fermentation broth of Bacillus sp. N11-8, which was isolated from the Antarctic waters, showed cytotoxicity towards different cells. A cytotoxic polypeptide, PBN11-8, was purified from the fermentation broth of Bacillus sp. N11-8 using ultrafiltration, ammonium sulfate precipitation, anion exchange liquid chromatography and high performance liquid chromatography (HPLC). Cloning and sequence analysis showed that PBN11-8 polypeptide (MW: ~19 kDa by the electrospray-ionization (ESI)) displayed high similarity with peptidase M84 from Bacillus pumilus. PBN11-8 possessed moderate cytotoxicity towards several cancer cell lines with IC₅₀ values of 1.56, 1.80, 1.57, and 1.73 µg/mL against human hepatocellular carcinoma cell line BEL-7402, human renal clear cell adenocarcinoma cell line 786-0, human hepatocellular carcinoma cell line HepG2, and human pancreatic cancer cell line Panc-28, respectively. Moreover, the polypeptide displayed weak cytotoxicity towards normal cell line renal tubular epithelial cell line HK2 and human normal liver cell line L02 cells. Wound healing migration and Transwell experiments demonstrate that PBN11-8 could inhibit the migration and invasion of BEL-7402. Further investigation revealed that PBN11-8 suppresses focal adhesion kinase (FAK)-mediated adhesion, migration, and invasion by disturbing FAK/extracellular regulated protein kinases (ERK) signaling and matrix metalloproteinase-2(MMP-2) and matrix metalloproteinase-9 (MMP-9) in BEL-7402 cells. Thus, PBN11-8 represents a potential novel anti-cancer lead compound.

Cordycepin induces apoptosis of human ovarian cancer cells by inhibiting CCL5-mediated Akt/NF-κB signaling pathway

The chemokine, CCL5, is a key mediator for the recruitment of immune cells into tumors and tissues. Akt/NF-κB signaling is significantly activated by CCL5. However, the role of NF-κB inactivation in apoptosis induced by negative regulation of CCL5 remains unclear. Here, we analyzed the effect of cordycepin on NF-κB activity in SKOV-3 cells and found that cordycepin-mediated inhibition of NF-κB signaling induced apoptosis in SKOV-3 cells via the serial activation of caspases. In addition, immune-blotting analysis showed that CCL5 is highly expressed in SKOV-3 cells. In addition to activating caspases, we show that, cordycepin prevents TNF-α-induced increase in CCL5, Akt, NF-κB, and c-FLIP_L activation and that CCL5 siRNA could inhibit Akt/NF-κB signaling. Moreover, cordycepin negatively regulated the TNF-α-mediated IκB/NF-κB pathway and c-FLIP_L activation to promote JNK phosphorylation, resulting in caspase-3 activation and apoptosis. Also, we show that c-FLIP_L is rapidly lost in NF-κB activation-deficient. siRNA mediated c-FLIP inhibition increased JNK. SP600125, a selective JNK inhibitor, downregulated p-JNK expression in cordycepin-treated SKOV-3 cells, leading to suppression of cordycepin-induced apoptosis. Thus, these results indicate that cordycepin inhibits CCL5-mediated Akt/NF-κB signaling, which upregulates caspase-3 activation in SKOV-3 cells, supporting the potential of cordycepin as a therapeutic agent for ovarian cancer.

CD31 regulates metastasis by inducing epithelial-mesenchymal transition in hepatocellular carcinoma via the ITGB1-FAK-Akt signaling pathway

Platelet endothelial cell adhesion molecule-1 (PECAM-1 or CD31) is a well-known marker of endothelial cells and a key factor for adhesion and accumulation of platelets. CD31 plays roles in cell proliferation, apoptosis, migration, and cellular immunity. CD31 is also expressed on tumor cells, such as breast cancer cells and non-Hodgkin's lymphomas, and contributes to tumor cell invasion. Here, our experiments show that CD31 promotes metastasis by inducing the epithelial-mesenchymal transition in hepatocellular carcinoma by up-regulating integrin β1 via the FAK/Akt signaling pathway.

Fluid shear stress induces epithelial-mesenchymal transition (EMT) in Hep-2 cells

Laryngeal squamous cell carcinoma (LSCC) is one of the most commonly diagnosed malignancies with high occurrence of tumor metastasis, which usually exposes to fluid shear stress (FSS) in lymphatic channel and blood vessel. Epithelial-mesenchymal transition (EMT) is an important mechanism that induces metastasis and invasion of tumors. We hypothesized that FSS induced a progression of EMT in laryngeal squamous carcinoma. Accordingly, the Hep-2 cells were exposed to 1.4 dyn/cm² FSS for different durations. Our results showed that most of cells changed their morphology from polygon to elongated spindle with well-organized F-actin and abundant lamellipodia/filopodia in protrusions. After removing the FSS, cells gradually recovered their flat polygon morphology. FSS induced Hep-2 cells to enhance their migration capacity in a time-dependent manner. In addition, FSS down-regulated E-cadherin, and simultaneously up-regulated N-cadherin, translocated β-catenin into the nucleus. These results confirmed that FSS induced the EMT in Hep-2 cells, and revealed a reversible mesenchymal-epithelial transition (MET) process when FSS was removed. We further examined the time-expressions of signaling cascades, and demonstrated that FSS induces the EMT and enhances cell migration depending on integrin-ILK/PI3K-AKT-Snail signaling events. The current study suggests that FSS, an important biophysical factor in tumor microenvironment, is a potential determinant of cell behavior and function regulation.

Cordycepin promotes apoptosis in renal carcinoma cells by activating the MKK7-JNK signaling pathway through inhibition of c-FLIPL expression

Cellular FLICE inhibitory protein (c-FLIP) is a key anti-apoptotic regulator that associates with the signaling complex downstream of NF-κB, negatively interfering with apoptotic signaling. The role of c-FLIP downregulation by negative regulation of NF-κB signaling during apoptosis is poorly understood. Here, we demonstrate that NF-κB-mediated c-FLIPL negatively regulates the JNK signaling pathway, and that cordycepin treatment of human renal cancer cells leads to apoptosis induction through c-FLIPL inhibition. TNF-α-induced inflammatory microenvironments stimulated NF-κB signaling and the c-FLIP long form (c-FLIPL) in TK-10 cells. Specifically, cordycepin inhibited TNF-α-mediated NF-κB activation, which induced renal cancer cell apoptosis. Cordycepin downregulated GADD45B and c-FLIPL, but upregulated MKK7 and phospho-JNK, by preventing nuclear mobilization of NF-κB. Furthermore, siRNA-mediated knockdown of GADD45B in cordycepin-treated TK-10 cells considerably increased MKK7 compared to cordycepin alone. siRNA-mediated knockdown of c-FLIPL prevented TNF-α-induced JNK inactivation, whereas c-FLIPL overexpression inhibited cordycepin-mediated JNK activation. The JNK inhibitor SP600125 strongly inhibited Bax expression. In nude mice, cordycepin significantly decreased tumor volume. Taken together, the results indicate that cordycepin inhibits TNF-α-mediated NF-κB/GADD45B signaling, which activates the MKK7-JNK signaling pathway through inhibition of c-FLIPL expression, thus inducing TK-10 cell apoptosis.

Cordycepin induces apoptosis by caveolin-1-mediated JNK regulation of Foxo3a in human lung adenocarcinoma

Forkhead transcription factor (Foxo3a) is a downstream effector of JNK-induced tumor suppression. However, it is not clear whether the caveolin-1 (CAV1)-mediated JNK/Foxo3a pathway is involved in cancer cell apoptosis. We found that cordycepin upregulates CAV1 expression, which was accompanied by JNK phosphorylation (p-JNK) and subsequent Foxo3a translocation into the nucleus, resulting in the upregulation of Bax protein expression. Furthermore, we found that CAV1 overexpression upregulated p-JNK, whereas CAV1 siRNA downregulated p-JNK. Additionally, SP600125, a specific JNK inhibitor, significantly increased Foxo3a phosphorylation, which downregulated Foxo3a translocation into the nucleus, indicating that CAV1 mediates JNK regulation of Foxo3a. Foxo3a siRNA downregulated Bax protein and attenuated A549 apoptosis, indicating that the CAV1-mediated JNK/Foxo3a pathway induces the apoptosis of A549 lung cancer cells. Cordycepin significantly decreased tumor volume in nude mice. Taken together, these results indicate that cordycepin promotes CAV1 upregulation to enhance JNK/Foxo3a signaling pathway activation, inducing apoptosis in lung cancer cells, and support its potential as a therapeutic agent for lung cancer.

Cordycepin disrupts leukemia association with mesenchymal stromal cells and eliminates leukemia stem cell activity

Maintaining stemness of leukemic stem cells (LSCs) and reciprocal interactions between leukemia and stromal cells support leukemic progression and resistance to chemotherapy. Targeting the niche-based microenvironment is thus a new approach for leukemia therapy. Cordycepin is an analogue of adenosine and has been suggested to possess anti-leukemia properties. However, whether cordycepin influences association of leukemia and mesenchymal stromal cells has never been investigated. Here we show that cordycepin reduces CD34⁺CD38⁻ cells in U937 and K562 cells and induces Dkk1 expression via autocrine and paracrine regulation in leukemia and mesenchymal stromal/stem cells (MSCs). Cordycepin suppresses cell attachment of leukemia with MSCs and downregulates N-cadherin in leukemia and VCAM-1 in MSCs. Moreover, incubation with leukemic conditioned media (CM) significantly induces IL-8 and IL-6 expression in MSCs, which is abrogated by cordycepin. Suppression of leukemic CM-induced VCAM-1 and IL-8 by cordycepin in MSCs is mediated by impairing NFκB signaling. Finally, cordycepin combined with an adenosine deaminase inhibitor prolongs survival in a leukemic mouse model. Our results indicate that cordycepin is a potential anti-leukemia therapeutic adjuvant via eliminating LSCs and disrupting leukemia-stromal association.

Cordycepin inhibits migration of human glioblastoma cells by affecting lysosomal degradation and protein phosphatase activation

Cordycepin, a nucleoside-derivative-isolated form Cordyceps militaris, has been reported to suppress tumor cell proliferation and cause apoptosis. This study investigates the effect of cordycepin on the migration of human glioblastoma cells. Cordycepin suppressed the migration of the human glioblastoma cell lines U87MG and LN229 in transwell and wound healing assays. Cordycepin decreased protein expression of integrin α1, focal adhesion kinase (FAK), p-FAK, paxillin and p-paxillin. The lysosomal inhibitor NH₄Cl blocked the ability of cordycepin to inhibit focal adhesion protein expression and glioma cell migration. In addition, the protein phosphatase inhibitors calyculin A and okadaic acid blocked the cordycepin-mediated reduction in p-Akt, p-FAK and migration. Hematoxylin and eosin staining of mouse xenografts demonstrated that cordycepin reduced brain tumor size in vivo. In conclusion, cordycepin inhibited migration of human glioblastoma cells by affecting lysosomal degradation and protein phosphatase activation. This pathway may be a useful target for clinical therapy in the future.

Metabolism, Biochemical Actions, and Chemical Synthesis of Anticancer Nucleosides, Nucleotides, and Base Analogs

Nucleoside, nucleotide, and base analogs have been in the clinic for decades to treat both viral pathogens and neoplasms. More than 20% of patients on anticancer chemotherapy have been treated with one or more of these analogs. This review focuses on the chemical synthesis and biology of anticancer nucleoside, nucleotide, and base analogs that are FDA-approved and in clinical development since 2000. We highlight the cellular biology and clinical biology of analogs, drug resistance mechanisms, and compound specificity towards different cancer types. Furthermore, we explore analog syntheses as well as improved and scale-up syntheses. We conclude with a discussion on what might lie ahead for medicinal chemists, biologists, and physicians as they try to improve analog efficacy through prodrug strategies and drug combinations.

Cordycepin Induces Apoptosis and Inhibits Proliferation of Human Lung Cancer Cell Line H1975 via Inhibiting the Phosphorylation of EGFR

Cordycepin is an active component of the traditional Chinese medicine Cordyceps sinensis and Cordyceps militaris with notable anticancer activity. Though the prominent inhibitory activity was reported in different kinds of cancer cell lines, the concrete mechanisms remain elusive. It was reported that cordycepin could be converted into tri-phosphates in vivo to confuse a number of enzymes and interfere the normal cell function. For the inhibitory mechanism of EGFR inhibitors and the structure similarity of ATP and tri-phosphated cordycepin, human lung cancer cell line H1975 was employed to investigate the inhibitory effect of cordycepin. The results showed that cordycepin could inhibit cell proliferation and induce apoptosis in a dose-dependent manner. Cell cycle analysis revealed that H1975 cells could be arrested at the G₀/G₁ phase after cordycepin treatment. The expression levels of apoptosis-related protein Caspase-3 and Bcl-2 and phosphorylated expression levels of EGFR, AKT and ERK1/2 were all decreased compared with the control group stimulated with EGF. However, the protein expression levels of proapoptotic protein Bax and cleaved caspase-3 were increased. These results implied that cordycepin could inhibit cell proliferation and induce apoptosis via the EGFR signaling pathway. Our results indicated that there was potential to seek a novel EGFR inhibitor from cordycepin and its chemical derivatives.

Relationship between integrin and epithelial-mesenchymal transition during invasion and metastasis of digestive system carcinomas

Invasion and metastasis are distinctive features of malignant tumors of the digestive system. Studies show that epithelial-mesenchymal transition (EMT), a conversion process with the loss of epithelial cell features and the gain of mesenchymal phenotype, has been recognized as a key element of invasion and metastasis of malignancies. When EMT occurs, down-regulation of E-cadherins and loss of adhesion in extracellular matrix play critical roles, which are regarded as important indicators in the assessment of EMT. Integrin, one of cell adhesion molecule families, is involved in EMT directly or indirectly through mediating either adhesion among cells and between cells and extracellular matrix, or signal pathways. This paper summarizes the relationship between EMT and integrin.

Cordycepin (3'-deoxyadenosine) suppressed HMGA2, Twist1 and ZEB1-dependent melanoma invasion and metastasis by targeting miR-33b

Malignant melanoma, the most deadly form of skin cancer, has a high propensity for metastatic spread and is notoriously chemotherapy-resistant. Cordycepin, the active component of Cordyceps spp., has been identified to have anti-metastatic effect on tumor progression and thus possesses pharmacological and therapeutic potentials. However, the mechanisms of anti-metastatic effects of cordycepin at cellular levels remain elusive. We analyzed the effect of cordycepin on human melanoma miRNA expression profiles by miRNAarray and found that miR-33b was upregulated in highly-metastatic melanoma cell lines following cordycepin exposure. Cordycepin-mediated miR-33b expression was dependent on LXR-RXR heterodimer activation. miR-33b directly binds to HMGA2, Twist1 and ZEB1 3'-UTR to suppress their expression. The negative correlations between miR-33b levels and HMGA2, Twist1 or ZEB1 expression were detected in 72 patient melanoma tissue samples. By targeting HMGA2 and Twist1, miR-33b attenuated melanoma migration and invasiveness upon cordycepin exposure. miR-33b knockdown or ZEB1 overexpression reverted cordycepin-mediated mesenchymal-epithelial transition (MET), triggering the expression of N-cadherin. In spontaneous metastasis models, cordycepin suppressed tumor metastasis without altering primary tumor growth. We showed for the first time that targeting miRNA by cordycepin indicates a new mechanism of cordycepin-induced suppression of tumor metastasis and miR-33b/HMGA2/Twist1/ZEB1 axis plays critical roles in regulating melanoma dissemination.

Preventive and Therapeutic Effects of Chinese Herbal Compounds against Hepatocellular Carcinoma

Traditional Chinese Medicines, unique biomedical and pharmaceutical resources, have been widely used for hepatocellular carcinoma (HCC) prevention and treatment. Accumulated Chinese herb-derived compounds with significant anti-cancer effects against HCC have been identified. Chinese herbal compounds are effective in preventing carcinogenesis, inhibiting cell proliferation, arresting cell cycle, inducing apoptosis, autophagy, cell senescence and anoikis, inhibiting epithelial-mesenchymal transition, metastasis and angiogenesis, regulating immune function, reversing drug resistance and enhancing the effects of chemotherapy in HCC. This paper comprehensively reviews these compounds and their effects on HCC. Finally, the perspectives and rational application of herbal compounds for HCC management are discussed.

Antrodia cinnamomea Inhibits Migration in Human Hepatocellular Carcinoma Cells: The Role of ERp57 and PGK-1

Evidences suggest that ERp57 and PGK-1 signaling lead to cancer cell proliferation and migration. We hypothesized that ERp57 and PGK-1 down-regulation may inactivate matrix metalloproteinase (MMP)-2, -9 expressions and inhibit hepatocellular carcinoma (HCC) migration. Antrodia cinnamomea is widely prescribed as an adjuvant to treat HCC in Taiwan. We aimed to investigate if ethanol extract of fruiting bodies of Antrodia cinnamomea (EEAC) and its active ingredients (i.e., zhankuic acid A, cordycepin, and adenosine) can modulate HCC cancer cells migration through ERp57 and PGK-1 and other molecular pathways such as PI3K/Akt and MAPK. ERp57 and PGK-1 siRNA were transfected into HCC to determine effects on MMP-2/-9 expressions and cell migration. We then examined the inhibitory effects of EEAC and its active ingredients on HCC migration and its related mechanisms including ERp57, PGK-1, PI3K/Akt, and MAPK signaling pathways. Down-regulation of ERp57 and PGK-1 by siRNA decreased MMP-2, -9 expressions and Transwell cell migration in HCC. Nontoxic EEAC markedly inhibited migration of HCC, and significantly inhibited activities and protein expressions of MMP-2 and -9, while the expression of the endogenous inhibitors (TIMP-1 and TIMP-2) of these proteins increased. Nontoxic EEAC and its active ingredients decreased ERp57, GLUD-1, GST-pi, and PGK-1 protein expressions. Finally, nontoxic EEAC inhibited the phosphorylated FAK, PI3K/Akt, and MAPK signaling. Our findings first indicate that EEAC and its ingredients effectively suppress HCC migration. Additionally, the molecular mechanisms appear to be mediated, in part, through the down-regulation of ERp57, PGK-1, MAPK, and PI3K/Akt.

Apoptosis and inhibition of proliferation of cancer cells induced by cordycepin

Cordycepin, a 3-deoxyadenosine, is the predominant functional component of the fungus Cordyceps militaris, a traditional Chinese medicine. Previous studies investigating the inhibition of cancer cells by cordycepin identified that it not only promotes cell apoptosis, but also controls cell proliferation. Furthermore, studies have elucidated the molecular mechanisms of inhibiting cell proliferation by cordycepin binding the A3 adenosine receptor, activating G protein, inhibiting cAMP formation, decreasing glycogen synthase kinase-3β/β-catenin activation and suppressing cyclin D1 and c-myc expression. The most significant signaling pathway in which cell apoptosis is induced by cordycepin is the caspase pathway. Cordycepin induces cell apoptosis via binding the DR3 receptor and consequently activating caspase-8/-3. Taken together, these studies demonstrate that cordycepin may be used as a natural medicine, as it can not only control tumor cell proliferation, but also induce cancer cell apoptosis.

Tissue invasion and metastasis: Molecular, biological and clinical perspectives

Cancer is a key health issue across the world, causing substantial patient morbidity and mortality. Patient prognosis is tightly linked with metastatic dissemination of the disease to distant sites, with metastatic diseases accounting for a vast percentage of cancer patient mortality. While advances in this area have been made, the process of cancer metastasis and the factors governing cancer spread and establishment at secondary locations is still poorly understood. The current article summarizes recent progress in this area of research, both in the understanding of the underlying biological processes and in the therapeutic strategies for the management of metastasis. This review lists the disruption of E-cadherin and tight junctions, key signaling pathways, including urokinase type plasminogen activator (uPA), phosphatidylinositol 3-kinase/v-akt murine thymoma viral oncogene (PI3K/AKT), focal adhesion kinase (FAK), β-catenin/zinc finger E-box binding homeobox 1 (ZEB-1) and transforming growth factor beta (TGF-β), together with inactivation of activator protein-1 (AP-1) and suppression of matrix metalloproteinase-9 (MMP-9) activity as key targets and the use of phytochemicals, or natural products, such as those from Agaricus blazei, Albatrellus confluens, Cordyceps militaris, Ganoderma lucidum, Poria cocos and Silybum marianum, together with diet derived fatty acids gamma linolenic acid (GLA) and eicosapentanoic acid (EPA) and inhibitory compounds as useful approaches to target tissue invasion and metastasis as well as other hallmark areas of cancer. Together, these strategies could represent new, inexpensive, low toxicity strategies to aid in the management of cancer metastasis as well as having holistic effects against other cancer hallmarks.

Marine bromophenol bis (2,3-dibromo-4,5-dihydroxy-phenyl)-methane inhibits the proliferation, migration, and invasion of hepatocellular carcinoma cells via modulating β1-integrin/FAK signaling

Bis (2,3-dibromo-4,5-dihydroxy-phenyl)-methane (BDDPM) is a natural bromophenol compound derived from marine algae. Previous reports have shown that BDDPM possesses antimicrobial activity. In the present study, we found that BDDPM has cytotoxic activity on a wide range of tumor cells, including BEL-7402 cells (IC₅₀ = 8.7 μg/mL). Further studies have shown that prior to the onset of apoptosis, the BDDPM induces BEL-7402 cell detachment by decreasing the adherence of cells to the extracellular matrix (ECM). Detachment experiments have shown that the treatment of BEL-7402 cells with low concentrations of BDDPM (5.0 μg/mL) significantly inhibits cell adhesion to fibronectin and collagen IV as well as cell migration and invasion. High doses of BDDPM (10.0 μg/mL) completely inhibit the migration of BEL-7402 cells, and the expression level of MMPs (MMP-2 and MMP-9) is significantly decreased. Moreover, the expression of β1-integrin and focal adhesion kinase (FAK) is found to be down-regulated by BDDPM. This study suggests that BDDPM has a potential to be developed as a novel anticancer therapeutic agent due to its anti-metastatic activity and also indicates that BDDPM, which has a unique chemical structure, could serve as a lead compound for rational drug design and for future development of anticancer agents.