Targeting Trop2 by Bruceine D suppresses breast cancer metastasis by blocking Trop2/ß-catenin positive feedback loop.

INTRODUCTION: Tumor-associated calcium signal transducer 2 (Trop2) has been used as a transport gate for cytotoxic agents into cells in antibody-drug conjugate designs because of its expression in a wide range of solid tumors. However, the specific role of Trop2 itself in breast cancer progression remains unclear and small molecules targeting Trop2 have not yet been reported. OBJECTIVES: To screen small molecules targeting Trop2, and to reveal its pharmacological effects and the molecular mechanisms of action. METHODS: Small molecule targeting Trop2 was identified by cell membrane chromatography, and validated by cellular thermal shift assay and point mutation analyses. We investigated the pharmacological effects of Trop2 inhibitor using RNA-seq, human foreskin fibroblast (HFF)-derived extracellular matrix (ECM), Matrigel drop invasion assays, colony-forming assay, xenograft tumor model, 4T1 orthotopic metastasis model and 4T1 experimental metastasis model. The molecular mechanism was determined using immunoprecipitation, mass spectrometry, immunofluorescence, immunohistochemistry and Western blotting. RESULTS: Here we identified Bruceine D (BD) as the inhibitor of Trop2, and demonstrated anti-metastasis effects of BD in breast cancer. Notably, Lys307 and Glu310 residues of Trop2 acted as critical sites for BD binding. Mechanistically, BD suppressed Trop2-induced cancer metastasis by blocking the formation of Trop2/ß-catenin positive loop, in which the Trop2/ß-catenin complex prevented ß-catenin from being degraded via the ubiquitin-proteosome pathway. Destabilized ß-catenin caused by BD reduced nucleus translocation, leading to the reduction of transcription of Trop2, the reversal of epithelial-mesenchymal transition (EMT) process, and the inhibition of ECM remodeling, further inhibiting cancer metastasis. Additionally, the inhibitory effects of BD on lung metastatic colonization and the beneficial effects of BD on prolongation of survival were validated in 4T1 experimental metastasis model. CONCLUSIONS: These results support the tumor-promoting role of Trop2 in breast cancer by stabilizing ß-catenin in Trop2/ß-catenin positive loop, and suggest Bruceine D as a promising candidate for Trop2 inhibition.

Harringtonine: A more effective antagonist for Omicron variant.

Fusion with host cell membrane is the main mechanism of infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we propose that a new strategy to screen small-molecule antagonists blocking SARS-CoV-2 membrane fusion. Using cell membrane chromatography (CMC), we found that harringtonine (HT) simultaneously targeted SARS-CoV-2 S protein and host cell surface TMPRSS2 expressed by the host cell, and subsequently confirmed that HT can inhibit membrane fusion. HT effectively blocked SARS-CoV-2 original strain entry with the IC50 of 0.217 µM, while the IC50 in delta variant decreased to 0.101 µM, the IC50 in Omicron BA.1 variant was 0.042 µM. Due to high transmissibility and immune escape, Omicron subvariant BA.5 has become the dominant strain of the SARS-CoV-2 virus and led to escalating COVID-19 cases, however, against BA.5, HT showed a surprising effectiveness. The IC50 in Omicron BA.5 was even lower than 0.0019 µM. The above results revealed the effect of HT on Omicron is very significant. In summary, we characterize HT as a small-molecule antagonist by direct targeting on the Spike protein and TMPRSS2.

Vandetanib drives growth arrest and promotes sensitivity to imatinib in chronic myeloid leukemia by targeting ephrin type-B receptor 4.

The oncogenic role of ephrin type-B receptor 4 (EPHB4) has been reported in many types of tumors, including chronic myeloid leukemia (CML). Here, we found that CML patients have a higher EPHB4 expression level than healthy subjects. EPHB4 knockdown inhibited growth of K562 cells (a human immortalized myelogenous leukemia cell line). In addition, transient transfection of EPHB4 siRNA led to sensitization to imatinib. These growth defects could be fully rescued by EPHB4 transfection. To identify an EPHB4-specific inhibitor with the potential of rapid translation into the clinic, a pool of clinical compounds was screened and vandetanib was found to be most sensitive to K562 cells, which express a high level of EPHB4. Vandetanib mainly acts on the intracellular tyrosine kinase domain and interacts stably with a hydrophobic pocket. Furthermore, vandetanib downregulated EPHB4 protein via the ubiquitin-proteasome pathway and inhibited PI3K/AKT and MAPK/ERK signaling pathways in K562 cells. Vandetanib alone significantly inhibited tumor growth in a K562 xenograft model. Furthermore, the combination of vandetanib and imatinib exhibited enhanced and synergistic growth inhibition against imatinib-resistant K562 cells in vitro and in vivo. These findings suggest that vandetanib drives growth arrest and overcomes the resistance to imatinib in CML via targeting EPHB4.

Selenium sulfide disrupts the PLAGL2/C-MET/STAT3-induced resistance against mitochondrial apoptosis in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. Overexpression of pleomorphic adenoma gene like-2 (PLAGL2) is associated with tumorigenesis. However, its function in HCC is unclear, and there are currently no anti-HCC drugs that target PLAGL2. Drug repositioning may facilitate the development of PLAGL2-targeted drug candidates. METHODS: The expression of PLAGL2 in HCC clinical tissue samples and HCC cell lines was analyzed by western blotting. The constructed HCC cell models were used to confirm the underlying function of PLAGL2 as a therapeutic target. Multiple in vitro and in vivo assays were conducted to determine the anti-proliferative and apoptosis-inducing effects of selenium sulfide (SeS2 ), which is clinically used for the treatment of seborrheic dermatitis and tinea versicolor. RESULTS: PLAGL2 expression was higher in HCC tumor tissues than in normal adjacent tissues. Its overexpression promoted the resistance of HCC cells of mitochondrial apoptosis through the regulation of the downstream C-MET/STAT3 signaling axis. SeS2 exerted significant anti-proliferative and apoptosis-inducing effects on HCC cells in a PLAGL2-dependent manner. Mechanistically, SeS2 suppressed C-MET/STAT3, AKT/mTOR, and MAPK signaling and triggered Bcl-2/Cyto C/Caspase-mediated intrinsic mitochondrial apoptosis both in vitro and in vivo. CONCLUSIONS: Our data reveal an important role of PLAGL2 in apoptosis resistance in HCC and highlight the potential of using SeS2 as a PLAGL2 inhibitor in patients with HCC.

WWOX activation by toosendanin suppresses hepatocellular carcinoma metastasis through JAK2/Stat3 and Wnt/ß-catenin signaling.

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide. Loss of WW-domain containing oxidoreductase (WWOX) has been proven to be associated with malignant metastasis in patients with HCC. In this study, by using a non-biased CRISPR knockout genetic screen targeting 19,050 human genes, we found that toosendanin (TSN) is a novel druggable WWOX candidate agonist for metastatic HCC patients. We also found that TSN exhibited significant anti-proliferative and anti-metastatic effects on HCC cells in a WWOX-dependent manner. Overexpression and knockdown of WWOX in vitro and in vivo confirmed that the suppression of HCC by TSN involved WWOX. TSN regulated Stat3, DVL2, and GSK3ß by transforming their interactions with WWOX as demonstrated by a Co-IP assay. TSN accelerated the degradation of ß-catenin by promoting the function of APC, AXIN1, CK1, and GSK3ß complex. Nuclear translocation of p-Stat3 Y705 and ß-catenin was impeded by the TSN-induced blockade of JAK2/Stat3 and Wnt/ß-catenin signaling, accompanied by the inhibition of MMPs and C-MYC.

Potential antiviral activity of isorhamnetin against SARS-CoV-2 spike pseudotyped virus in vitro.

Coronavirus Disease 2019 (COVID-19) cases and deaths are still rising worldwide, there is currently no effective treatment for severe inflammation and acute lung injury caused by new coronavirus (SARS-COV-2) infection. Therapies to prevent or treat COVID-19, including antiviral drug and several vaccines, are still being development. Human angiotensin-converting enzyme 2 (ACE2), expressing in lung, has been confirmed to be a receptor for SARS-COV-2 infection, interventions for attachment of spike protein of SARS-CoV-2 to ACE2 may be a potential approach to prevent viral infections and it is considered as a potential target for drug development. In this study, we observed that seabuckthorn and its flavonoid compounds quercetin and isorhamnetin were shown strong retention to ACE2 overexpression HEK293 (ACE2h ) cells by CMC analysis. Based on drug receptor interaction analysis and viral entry studies in vitro, we evaluated the interaction of two flavonoid compounds and ACE2 as well as the inhibitory effect of the two compounds on viral entry. Surface plasmon resonance assay proved the effect that isorhamnetin bound to the ACE2, and its affinity (KD value) was at the micromolar level, that was, 2.51 ± 0.68 µM. Viral entry studies in vitro indicated that isorhamnetin inhibited SARS-CoV-2 spike pseudotyped virus entering ACE2h cells. Based on promising in vitro results, we proposed isorhamnetin to be a potential therapeutic candidate compound against COVID-19.

Chloroquine and hydroxychloroquine as ACE2 blockers to inhibit viropexis of 2019-nCoV Spike pseudotyped virus.

BACKGROUND: The novel coronavirus disease (2019-nCoV) has been affecting global health since the end of 2019 and there is no sign that the epidemic is abating . The major issue for controlling the infectious is lacking efficient prevention and therapeutic approaches. Chloroquine (CQ) and Hydroxychloroquine (HCQ) have been reported to treat the disease, but the underlying mechanism remains controversial. PURPOSE: The objective of this study is to investigate whether CQ and HCQ could be ACE2 blockers and used to inhibit 2019-nCoV virus infection. METHODS: In our study, we used CCK-8 staining, flow cytometry and immunofluorescent staining to evaluate the toxicity and autophagy of CQ and HCQ, respectively, on ACE2 high-expressing HEK293T cells (ACE2h cells). We further analyzed the binding character of CQ and HCQ to ACE2 by molecular docking and surface plasmon resonance (SPR) assays, 2019-nCoV spike pseudotyped virus was also used to observe the viropexis effect of CQ and HCQ in ACE2h cells. RESULTS: Results showed that HCQ is slightly more toxic to ACE2h cells than CQ. Both CQ and HCQ could bind to ACE2 with KD = (7.31 ± 0.62)e-7 M and (4.82 ± 0.87)e-7 M, respectively. They exhibit equivalent suppression effect for the entrance of 2019-nCoV spike pseudotyped virus into ACE2h cells. CONCLUSIONS: CQ and HCQ both inhibit the entrance 2019-nCoV into cells by blocking the binding of the virus with ACE2. Our findings provide novel insights into the molecular mechanism of CQ and HCQ treatment effect on virus infection.

Cantharidin treatment inhibits hepatocellular carcinoma development by regulating the JAK2/STAT3 and PI3K/Akt pathways in an EphB4-dependent manner.

Hepatocellular carcinoma (HCC) is a lethal malignancy with limited treatment options. The tyrosine kinase receptor EphB4 promotes oncogenesis and tumor development and progression. Its inhibition is regarded as an effective strategy for the treatment of solid tumors. In the present study, we identified cantharidin as a novel EphB4 inhibitor for HCC treatment and evaluated the underlying molecular pharmacological mechanisms of action. We observed increased expression levels of EphB4 in HCC patients and a positive correlation between EphB4 and p-JAK2 levels in HCC patient samples. Knockdown of EphB4 using small interfering RNA decreased the expression levels of p-JAK2 and p-STAT3 in HCC cells, suggesting JAK2/STAT3 being a novel downstream signaling target of EphB4. Cell viability experiments revealed that the anti-cancer effect of cantharidin was positively correlated with EphB4 expression levels in HCC cell lines. We confirmed the potent antiproliferative activity of cantharidin on HepG2 cells with high expression of EphB4 and tumor xenograft. Molecular docking assay, immunoblotting assay and quantitative reverse transcription PCR assay indicated that cantharidin bound to EphB4, and thereby resulted in EphB4 suppression at mRNA and protein levels. Hep3B and SMMC-7721 cells were with low expression of EphB4. In EphB4-/HepG2, EphB4+/HepG2, and EphB4+/Hep3B cells, EphB4 knockdown alleviated the cantharidin-induced decrease in cell viability and colony formation ability and increase in apoptosis in HepG2 cells, while its overexpression exacerbated these effects in Hep3B cells and increased the apoptosis of HepG2 cells. In nude mouse models, cantharidin suppressed tumor growth more effectively in EphB4+/SMMC-7721 xenografts than in wild-type SMMC-7721 xenografts. Underlying mechanistic study showed that by targeting EphB4, cantharidin blocked a novel target, the downstream JAK2/STAT3 pathway, and the previously known target, the PI3K/Akt signaling, resulting in intrinsic apoptosis. These results indicated that cantharidin may be a potential candidate for HCC treatment by regulating the EphB4 signaling pathway.

Sanguinarine disrupts the colocalization and interaction of HIF-1α with tyrosine and serine phosphorylated-STAT3 in breast cancer.

Breast cancer is one leading cause of death in females, especially triple-negative breast cancer (TNBC). Hypoxia is a key feature leading to tumour progression driven by hypoxia-inducible factor (HIF)-1α. The aim is to investigate the mechanism of HIF-1α and signal transducer and activator of transcription-3 (STAT3) interaction and discover a compound to disrupt the interaction in breast cancer cells. The regulation pattern of HIF-1α and STAT3 was analysed in hypoxic TNBC cells and patient samples. The effects of a natural alkaloid, sanguinarine, on HIF-1α and STAT3 colocalization and interaction were evaluated in vitro and mouse xenograft models. We observed strong colocalization of HIF-1α, p-STAT3-Tyr and p-STAT3-Ser in TNBC patient samples. Sanguinarine could inhibit the nuclear colocalization and interaction of HIF-1α with p-STAT3-Tyr and p-STAT3-Ser in vivo and in vitro. Our results may bring insights to the HIF-1α/STAT3 interaction in breast cancers and suggest sanguinarine as a promising candidate for HIF-α/STAT3 inhibition.

Electrodeposited poly(3,4-ethylenedioxythiophene) doped with graphene oxide for the simultaneous voltammetric determination of ascorbic acid, dopamine and uric acid.

Poly(3,4-ethylenedioxythiophene) (PEDOT) films were electrodeposited by cyclic voltammetry on a glassy carbon electrode (GCE) in aqueous solution. Three kinds of supporting electrolytes were used, viz. graphene oxide (GO), phosphate buffered saline (PBS), and GO in PBS, respectively. The surface morphology of the modified electrodes was characterized by scanning electron microscopy. The electrochemical performance of the modified electrodes was investigated by cyclic voltammetry and electrochemical impedance spectroscopy by using the hexacyanoferrate redox system. The results demonstrate that the PEDOT-GO/GCE, which was electropolymerized in aqueous solutions containing EDOT and GO, shows the best electrochemical activities compared with other modified electrodes. The electrochemical behaviors of ascorbic acid (AA), dopamine (DA) and uric acid (UA) were investigated by cyclic voltammetry. The PEDOT-GO/GCE exhibits enhanced electrocatalytic activities towards these important biomolecules. Under physiological pH conditions and in the mixed system of AA, DA and UA, the modified GCE exhibits the following figures of merit: (a) a linear voltammetric response in the concentration ranges of 100-1000 µM for AA, 6.0-200 µM for DA, and 40-240 µM for UA; (b) well separated oxidation peaks near 31, 213 and 342 mV (vs. saturated Ag/AgCl) for AA, DA and UA, respectively; and (c) detection of limits (at S/N = 3) of 20, 2.0 and 10 µM. The results demonstrate that GO, based on its relatively large number of anionic sites, can be used as the sole weak electrolyte and charge balance dopant for the preparation of functionally doped conducting polymers by electrodeposition. Graphical abstractSchematic representation of a nanostructure composed of hybrid conducting polymer PEDOT-GO nanocomposites, and its application to simultaneous determination of ascorbic acid, dopamine and uric acid.

Sanguinarine inhibits epithelial-mesenchymal transition via targeting HIF-1α/TGF-ß feed-forward loop in hepatocellular carcinoma.

Epithelial-mesenchymal transition (EMT) plays a crucial role in hepatocellular carcinoma (HCC) progression. Hypoxia and excessive transforming growth factor-ß (TGF-ß) have been identified as inducers and target for EMT in HCC. Here, we show hypoxia inducible factor-1α (HIF-1α) and TGF-ß form a feed-forward loop to induce EMT in HCC cells. Further mechanistic study indicates under both hypoxia and TGF-ß stimulation, Smad and PI3K-AKT pathways are activated. We show sanguinarine, a natural benzophenanthridine alkaloid, impairs the proliferation of nine kinds of HCC cell lines and the colony formation of HCC cells. In hypoxic and TGF-ß cell models, sanguinarine inhibits HIF-1α signaling and the expression of EMT markers, translocation of Snail and activation of both Smad and PI3K-AKT pathways. Sanguinarine could also inhibit TGF-ß-induced cell migration in HCC cells. In vivo studies reveal that the administration of sanguinarine inhibits tumor growth and HIF-1α signaling, inhibits the expression changes of EMT markers as well as Smad and PI3K-AKT pathway proteins. Our findings suggest that sanguinarine is a promising candidate targeting HIF-1α/TGF-ß signaling to improve the treatment for HCC patients.

A Connective Tissue Mast-Cell-Specific Receptor Detects Bacterial Quorum-Sensing Molecules and Mediates Antibacterial Immunity.

Quorum-sensing molecules (QSMs) are secreted by bacteria to signal population density. Upon reaching a critical concentration, QSMs induce transcriptional alterations in bacteria, which enable virulence factor expression and biofilm formation. It is unclear whether mammalian hosts can recognize QSMs to trigger responsive antibacterial immunity. We report that mouse mast-cell-specific G-protein-coupled receptor Mrgprb2 and its human homolog MRGPRX2 are receptors for Gram-positive QSMs, including competence-stimulating peptide (CSP)-1. CSP-1 activates Mrgprb2 and MRGPRX2, triggering mast cell degranulation, which inhibits bacterial growth and prevents biofilm formation. Such antibacterial functions are reduced in Mrgprb2-deficient mast cells, while wild-type mast cells fail to inhibit the growth of bacterial strains lacking CSP-1. Mrgprb2-knockout mice exhibit reduced bacterial clearance, while pharmacologically activating Mrgprb2 in vivo eliminates bacteria and improves disease score. These findings identify a host defense mechanism that uses QSMs as an "Achilles heel" and suggest MRGPRX2 as a potential therapeutic target for controlling bacterial infections.

Polymyxin B and polymyxin E induce anaphylactoid response through mediation of Mas-related G protein-coupled receptor X2.

Polymyxin B (PMB) and polymyxin E (PME) are cyclic, peptide antibiotics which derived from various species of Paenibacillus (Bacillus) polymyxa. They are decapeptide antibiotics with an antimicrobial spectrum that includes Gram-negative bacteria, and reused as therapeutic agents due to the emergence of multidrug-resistant (MDR) Gram-positive bacteria. PMB or PME-induced anaphylactoid reactions in the clinic have been documented. However, the mechanism underlying anaphylactoid reaction induced by polymyxin has not yet been reported. Here, we report that human Mas-related G protein-coupled receptor X2 (MRGPRX2) and its mouse homologue Mas-related G protein-coupled receptor B2 (MrgprB2) are the receptors mediating the anaphylactoid response provoked by PMB and PME. We firstly investigated the anaphylactoid reactions induced by PMB and PME in LAD2 cells in vitro and in vivo, and found that treatment with PMB and PME led to significant release of mast cell granules such as histamine and ß-hexosaminidase, secretion of pro-inflammatory cytokines, such as TNF-α and PGD2, and provocation of calcium flux in LAD2 cells. Furthermore, treatment with PMB and PME led to reduced release of ß-hexosaminidase in MRGPRX2 knockdown-LAD2 cells, and obvious increased calcium release in MRGPRX2 overexpressing HEK293 cells, which suggested that MRGPRX2 are involved in mast cell activation provoked by PMB or PME. In vivo, MRGPRB2 knockout mice exhibited lower pseudo-allergic reactions than wild type mice. Activation of MrgprB2 also triggers increased capillary permeability and paw swelling. Our results elucidated the role of MRGPRX2 in PMB and PME-induced anaphylactoid response and suggested that MRGPRX2 as a potential therapeutic target to control the anaphylactoid reactions which triggered by PMB or PME.

Prognostic values of S100 family mRNA expression in ovarian cancer.

S100 family is made up of at least 20 calcium-binding proteins which are involved in many cellular processes. The prognostic values of individual S100 member in ovarian cancer patients are still unknown. In this study, we performed a detailed prognostic values of S100 in ovarian cancer. The mRNA expression levels of S100 family in various cancers were analyzed via the Oncomine, and the protein-protein interaction network of S100 family was analyzed via String. The prognostic values of individual S100 member were evaluated via Kaplan-Meier Plotter. The S100 family genes expression and mutation were analyzed via cBioProtal. We observed that the mRNA expression of most S100 family were overexpressed in ovarian cancer compared with normal tissues. In survival analysis in Kaplan-Meier Plotter, 10 members of S100 family showed significant correlation with overall survival in ovarian cancer patients. The trends of high expression of individual S100 members were nearly the same in different subtype and pathological grades. However, the S100 family genes expression and mutation showed no significant prognostic values in overall survival and disease free survival in ovarian cancer patients. Although, the results need more verification both in clinical trials and fundamental experiments, our study provide new insights for the prognostic function of S100 family in ovarian cancer and might promote development of S100 targeted inhibitors for the new treatment of ovarian cancer.

A novel biphenyl urea compound, TPD7, stimulates apoptosis through modulating Fas signaling and Bcl-2 family proteins in cervical cancer.

We recently reported that TPD7 suppressed tumor cell proliferation, and inhibited invasion, through the suppression of C-X-C chemokine receptor type 4 (CXCR4). In the present study, we investigated the anticancer effect of TPD7 on apoptosis and invasion of cervical cancer HeLa cells. Cell cycle analysis revealed that TPD7 decreased cyclin-dependent kinase (CDK)1 and cyclin D1 expression, and increased cyclin A expression, following S phase blockade. TPD7 induced chromatin condensation and significantly elevated the number of apoptotic cells, suggesting that its inhibitory effect on HeLa cells was due to the induction of cell cycle blockade and apoptosis. Mechanistically, TPD7 altered the extrinsic apoptosis pathway by upregulating Fas expression, and the intrinsic pathway by modulating Bcl-2 family proteins, p53, and NF-κB p65, leading to enhanced apoptosis. TPD7 inhibited HeLa cell invasion by downregulating the expression of matrix metalloproteinase (MMP)-9 and CXCR4 proteins. In vivo experiments revealed that TPD7 inhibited tumor growth in HeLa cell xenografted mice. These findings indicated that TPD7 may be a potential chemoprevention agent for the management of cervical carcinoma.

Typical antimicrobials induce mast cell degranulation and anaphylactoid reactions via MRGPRX2 and its murine homologue MRGPRB2.

Mast cells are unique immune cells that function as sentinels in host defence reactions, including immediate hypersensitivity responses and allergic responses. The mast cell-specific receptor named MAS-related G protein-coupled receptor X2 (MRGPRX2) triggers mast-cell degranulation, a key process in anaphylactoid reactions. It is widely observed that antimicrobials can induce pseudo-allergic reactions (i.e. IgE-independent mechanism) with symptoms ranging from skin inflammation to life-threatening systemic anaphylaxis. However, their direct involvement and the mechanisms underlying anaphylactoid reactions caused by antimicrobials have not been demonstrated. Structurally different antimicrobials were screened by Ca2+ imaging using MRGPRX2 overexpressing HEK293 cells. MRGPRX2 related anaphylactoid reactions induced by these components were investigated by body temperature drop and mast cell degranulation assays. We showed that MRGPRX2 is involved in allergic-like reactions to three types of antimicrobials in a dose-dependent manner. However, mast cells lacking the receptor show reduced degranulation. Furthermore, mice without MAS-related G protein-coupled receptor B2 (the orthologous gene of MRGPRX2) exhibited reduced substance-induced inflammation. Interestingly, ß-lactam and antiviral nucleoside analogues did not induce anaphylactic reactions, which were also observed in vitro. These results should alarm many clinicians that such drugs might induce anaphylactoid reactions and provide guidance on safe dosage of these drugs.

Dihydroberberine exhibits synergistic effects with sunitinib on NSCLC NCI-H460 cells by repressing MAP kinase pathways and inflammatory mediators.

Highly effective and attenuated dose schedules are good regimens for drug research and development. Combination chemotherapy is a good strategy in cancer therapy. We evaluated the antitumour effects of dihydroberberine combined with sunitinib (DCS) on the human non-small cell lung cancer cell lines (NSCLC), A549, NCI-H460, and NCI-H1299 in vitro and in vivo. DCS showed synergic effects on NCI-H460 cell proliferation, colony formation and transplantable tumour growth, which suggested dihydroberberine increases the sensitivity of lung carcinoma to sunitinib. Further studies indicated that DCS down-regulated phosphorylation of JNK, p38, and NF-κB in NCI-H460 cells and tumours and suppressed the IκB and COX-2 expression. In addition, DCS reduced the secretion of the pro-inflammatory cytokine, interleukin-1 (IL-1), in tumours. Inhibition of p38 activation by DCS was a likely contributing factor in IL-1 and COX-2 down-regulation. Consistent with these results, a genomewide microarray analysis found that DCS induced the expression of cell cycle signal molecules that are known to be affected by JNK and p38. The change of cell cycle, in turn, led to down-regulation of JNK and p38, and further reduced IL-1 secretion. Collectively, these findings highlight potential molecular mechanisms of DCS chemotherapeutic activity and suggest that DCS is an efficacious strategy in NSCLC therapy.

Eupolyphaga sinensis Walker Ethanol Extract Suppresses Cell Growth and Invasion in Human Breast Cancer Cells.

AIM OF THE STUDY: To examine the antiproliferation and anti-invasion of Eupolyphaga sinensis Walker 70% ethanol extract (ESWE) on breast cancer and elucidate the underlying signaling mechanisms. METHODS: MTT and colony formation assays were used to investigate the effect of ESWE on proliferation of breast cancer cells in vitro. The xenograft mouse tumor model was used to determine the effect of ESWE on breast cancer in vivo. To investigate the underlying molecular mechanisms, we used western blotting to analyze the expression of ERK1/2, CXCR4, matrix metalloproteinase 2 (MMP2), and MMP9 pretreated with ESWE. The stromal cell-derived factor (SDF)-1α-induced migration and invasion potential of breast cancer cells were examined by wound-healing assays and Matrigel invasion chamber assays. RESULTS: ESWE effectively inhibited the proliferation of MDA-MB-435s and MDA-MB-231 cells and exhibited antitumor effects in an MDA-MB-231 xenograft mice model. Furthermore, ESWE suppressed the activity of ERK1/2, a key molecule of MAPK signaling. We also observed that ESWE treatment led to downregulation of CXCR4 expression as well as greatly reduced MMP2 and MMP9. ESWE affected CXCR4 expression partially through the modulation of autocrine vascular endothelial growth factor. However, suppression of CXCR4 expression was the result of downregulation of mRNA expression. Inhibition of CXCR4 expression by ESWE further correlated with the suppression of SDF-1α-induced migration and invasion in breast cancer cells. CONCLUSION: ESWE exerted its antiproliferation and antiinvasion by regulating MAPK signaling and related metastasis factorsand thus could be a useful therapeutic candidate for breast cancer intervention.

Total saponins isolated from Radix et Rhizoma Leonticis suppresses tumor cells growth by regulation of PI3K/Akt/mTOR and p38 MAPK pathways.

Both PI3K/AKT/mTOR and mitogen activated protein kinase (MAPK) signaling cascades played an important role in tumorigenesis, a more complete understanding of these signaling pathways allowed the development of new therapeutic strategies. Total saponins isolated from Radix et Rhizoma Leonticis (RLTS) was recognized with anticancer properties. In a murine hepatocellular carcinoma H22 cell-bearing mouse model, RLTS exhibited significant inhibitory effect on tumor growth. Here, we investigated the role of RLTS on the PI3K/AKT/mTOR signaling pathway and MAPK pathways in liver and lung cancer cells. Results obtained showed RLTS inhibited cell proliferation and induced cell apoptosis in vitro, which attributed to the inhibition on the activation of PI3K/AKT/mTOR cascade and its related signaling molecules, such as activated VEGFR and NF-κB, and activation of p38 MAPK in tumor cells. Additional, RLTS inhibited cell migration and downregulated proteins that mediated metastasis including CXCR4, MMP2 and MMP9. Overall, these findings suggested that RLTS interfered with multiple signaling cascades involved in tumorigenesis and had potential in cancer therapy.

Momordica cochinchinensis Spreng. seed extract suppresses breast cancer growth by inducing cell cycle arrest and apoptosis.

The herb Momordica cochinchinensis has been used for a variety of purposes, and been shown to have anti­cancer properties. The present study assessed the potency and the underlying mechanisms of action of the ethyl acetate extract of seeds of Momordica cochinchinensis (ESMC2) on breast cancer cells. Therefore, the effects of ESMC2 on the cell viability, cell cycle and apoptosis of MDA­MB­231 cells were investigated. The results showed that ESMC2 exerted a marked growth inhibitory effect on the cells. Cell cycle arrest in G2 phase following treatment with ESMC2 was associated with a marked increase in the protein levels of cyclin B1, cyclin E and cyclin-dependent kinase 1 and a decrease in cyclin D1 expression. In addition, ESMC2 dose­dependently induced cell apoptosis, which was mediated via upregulation of the apoptosis-associated proteins p53, B-cell lymphoma 2 (Bcl­2)­associated X protein, Bcl-2 homologous antagonist killer and Bcl-2-associated death promoter expression, as well as downregulation of nuclear factor kappa B, Bcl­2 and myeloid cell leukemia­1. Furthermore, the activation of extracellular signal-regulated kinase 1/2, p38, c-Jun N-terminal kinase (JNK) and Akt phosphorylation were decreased by ESMC2 in a dose­dependent manner, indicating that ESMC2 exerted its effects via the mitogen-activated protein kinase/JNK pathway. Furthermore, nude mouse xenotransplant models were used to evaluate the tumor growth inhibitory effects of ESMC2. The possible chemical components of ESMC2 were analyzed by gas chromatography-mass spectrometry, and 12 compounds were detected from the major peaks based on the similarity index with entries of a compound database. The results of the present study may aid in the development of novel therapies for breast cancer.