Asperolide A induces apoptosis and cell cycle arrest of human hepatoma cells with p53-Y220C mutant through p38 mediating phosphorylation of p53 (S33).

Asperolides A (AA), one of the new tetranorlabdane diterpenoids, is proved to inhibit the proliferation of lung cancer cells and bone metastasis of breast cancer cells. Herein, we report that AA induces apoptosis and cell cycle arrest of hepatoma cells. It intensely inhibits proliferation of Huh-7 cell, compared with HepG-2 and L02 cells. AA elevates the activity of mitogen-activated protein kinases (MAPKs), in which the activation of ERK and JNK improves cell survival. However, phosphorylation of p53 at S33 by p38 activation could be a principal factor in the AA-induced apoptosis and G2/M cell cycle arrest of Huh-7 cells. The S33 site of p53-Y220C mutant, as the specific activation site of p38, reactivates the wild-type function of mutant p53 protein, which leads to a higher sensitivity of Huh-7 cells to AA. These results provide new insights into the molecular mechanisms of AA as a developing mutant p53 rescue drug.

The discovery of subunit-selective GluN1/GluN2B NMDAR antagonist via pharmacophere-based virtual screening.

The incidence and mortality rates of neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease, are gradually increasing worldwide. Numerous studies have demonstrated that N-methyl-D-aspartic acid receptor (NMDAR)-mediated excitotoxicity contributes to neurodegenerative diseases. Ifenprodil, a subtype-selective NMDAR antagonist, showed strong therapeutic potential. However, it suffers from low oral bioavailability and off-target side effects. In this study, natural compounds were identified for selective inhibition of GluN1/GluN2B NMDAR of human. We obtained a set of natural compounds (n = 81,366) from COCONUT, TIPdb, PAMDB, CMNPD, YMDB, and NPAtlas databases, and then virtually screened by an ifenprodil-structure-based pharmacophore model and molecular docking. The top 100 compounds were selected for binding affinity prediction via batch drug-target affinity (BatchDTA). Then, the top 50 compounds were analyzed by absorption, distribution, metabolism, excretion, toxicity (ADMET). Molecular dynamics involving molecular mechanics/position-Boltzmann surface area (MM-PBSA) calculation were performed to further screening. The top 15 compounds with strong binding affinity and ifenprodil, a proven GluN2B-selective NMDAR antagonist, were subjected to molecular dynamic simulations (100 ns), root-mean-square deviation (RMSD), root-mean-square fluctuation (RMSF), radius of gyration (Rg), H-bonds, solvent accessible surface area (SASA), principal component analysis (PCA), and binding free energy calculations. Based on these analyses, one possible lead compound carrying positive charges (CNP0099440) was identified, with great binding affinity and less off-target activity by contrast to ifenprodil. CNP0099440 has great potential to be a GluN1/GluN2B NMDAR antagonist candidate and can be further detected via in vitro and in vivo experiments.

Wentilactone A Reverses the NF-κB/ECM1 Signaling-Induced Cisplatin Resistance through Inhibition of IKK/IκB in Ovarian Cancer Cells.

Wentilactone A (WA) is a tetranorditerpenoid isolated from marine algae. We previously found that WA inhibited cancer cell proliferation with little toxicity. In this study, we show that high expression of extracellular matrix protein-1 (ECM1) promotes cancer cell cisplatin resistance, and the secreted ECM1 activates normal fibroblasts (NFs) to transform cells with characteristics of cancer-associated fibroblasts (CAFs). Transcription of the ECM1 gene is regulated largely by NF-κB through EP881C/T-EP266C binding sites. WA supresses the phosphorylation of NF-κB through inhibition of the upstream IKK/IκB phoshorylation to block the expression of ECM1, which reverses the cisplatin-induced activation of NF-κB/ECM1. On the contrary, cisplatin facilitates phosphorylation of NF-κB to enhance the expression of ECM1. These results highlight ECM1 as a potential target for treatment of cisplatin-resistant cancers associated with the ECM1 activated signaling. In addition, WA reverses cisplatin resistance by targeting both tumor cells and the tumor microenvironment through IKK/IκB/NF-κB signaling to reduce the expression of the ECM1 protein.

Soft coral-derived Aspernolide A suppressed non-small cell lung cancer induced osteolytic bone invasion via the c-Fos/NFATC1 signaling pathway.

BACKGROUND: the incidence of distant metastases is over 30% in advanced non-small cell lung cancer (NSCLC) patients. In particular, bone is reported as the most common site of distant metastasis NSCLC. Bone metastases (BM) have a consequence of serious skeletal-related events (SREs) leading to the reduced overall survival (OS) and quality of life of NSCLC patients. Inhibition of osteolytic lesions and regulation crosstalk between metastatic NSCLC cells and bone microenvironment are the key to treating NSCLC. Due to the lack of effective treatments against NSCLC with bone metastasis, screening and identification of novel agents against both NSCLC and osteoclast effects are critically needed. METHODS: We assessed the effects of Aspernolide A (AA) on osteolysis and RANKL-induced pathways activation, bone resorption and F-actin ring formation in vitro. We evaluated AA effects on NCI-H460 and A549 cells in vitro through wound healing assay and transwell assay. Furthermore, we assessed the effects of AA in vivo using an intratibial xenograft NSCLC nude mouse model, followed by micro-computed tomography(micro-CT) and TRAcP staining. RESULTS: in our study, AA, a soft coral-derived agent, was shown to inhibit osteoclastogenesis via suppression of nuclear factor (NF)-κBp65, ERK, AKT and P38 phosphorylation, and then suppress the RANKL-induced c-Fos and NFATc1 activities in bone marrow macrophages (BMMs). Furthermore, AA reduced the migration and invasion of NSCLC cells through diminishing the expression of MMP9, MMP7, and N-cadherin proteins and upregulating E-cadherin expression in vitro, as well as inhibited the phosphorylation of ERK, AKT, P38, and NF-κBp65. It was also demonstrated that administration of AA could help prevent NSCLC-induced bone destruction by attenuating NSCLC development and osteoclast activity in vivo. CONCLUSIONS: collectively, these findings indicated that Aspernolide A is a potential candidate for NSCLC-induced osteolytic bone destruction.

Cordyceps sinensis aqueous extract regulates the adaptive immunity of mice subjected to 60 Co γ irradiation.

Cordyceps sinensis (CS) is a traditional Chinese medicine that is known for treating various diseases, and particularly for exerting therapeutic effects in immune disorders. The adaptive immunoregulatory effects of CS aqueous extract (CSAE) on γ-irradiated mice have not been reported previously. The study aimed to evaluate the therapeutic effects of CSAE in mice immunosuppressed by irradiation. We observed that CSAE administration significantly increased body weight and spleen index, as well as the number of white blood cells, lymphocytes, and platelets in peripheral blood, T and B lymphocytes in spleen tissue, and total serum immunoglobulins in irradiated mice, whereas total serum pro-inflammatory cytokine levels were decreased. Collectively, CSAE maintained the structural integrity of spleen tissue and repaired its damage in irradiated mice as shown by hematoxylin and eosin staining, and decreased the number of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive splenocytes. Mechanistically, CSAE upregulated Bcl-2, and downregulated Bax and cleaved caspase-3 in spleen of irradiated mice. However, there were no significant differences in red blood cells and neutrophils in different groups. The results revealed that CSAE had protective effects against irradiation-induced immunosuppression, which was likely associated with an antiapoptotic effect and the regulation of adaptive immunity.

Comprehensive analysis of suppressor of cytokine signaling proteins in human breast Cancer.

BACKGROUND: Abnormal expression of suppressor of cytokine signaling (SOCS) proteins regulates tumor angiogenesis and development in cancers. In this study, we aimed to perform a comprehensive bioinformatic analysis of SOCS proteins in breast invasive carcinoma (BRCA). METHODS: The gene expression, methylation level, copy number, protein expression and patient survival data related to SOCS family members in BRCA patients were obtained from the following databases: Oncomine, The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), Human Protein Atlas (HPA), Gene Expression Profiling Interactive Analysis (GEPIA), PCViz, cBioPortal and Kaplan-Meier plotter. Correlation analyses, identification of interacting genes and construction of regulatory networks were performed by functional and pathway enrichment analyses, weighted gene coexpression network analysis (WGCNA) and gene set enrichment analysis (GSEA). RESULTS: Data related to 1109 BRCA tissues and 113 normal breast tissue samples were extracted from the TCGA database. SOCS2 and SOCS3 exhibited significantly lower mRNA expression levels in BRCA tissues than in normal tissues. BRCA patients with high mRNA levels of SOCS3 (p < 0.01) and SOCS4 (p < 0.05) were predicted to have significantly longer overall survival (OS) times. Multivariate analysis showed that SOCS3 was an independent prognostic factor for OS. High mRNA expression levels of SOCS2 (p < 0.001), SOCS3 (p < 0.001), and SOCS4 (p < 0.01), and a low expression level of SOCS5 (p < 0.001) were predicted to be significantly associated with better recurrence-free survival (RFS). Multivariate analysis showed that SOCS2 was an independent prognostic factor for RFS. Lower expression levels of SOCS2 and SOCS3 were observed in patients with tumors of more advanced clinical stage (p < 0.05). Functional and pathway enrichment analyses, together with WGCNA and GSEA, showed that SOCS3 and its interacting genes were significantly involved in the JAK-STAT signaling pathway, suggesting that JAK-STAT signaling might play a critical role in BRCA angiogenesis and development. Western blot results showed that overexpression of SOCS3 inhibited the activity of the JAK-STAT signaling pathway in vitro. CONCLUSIONS: SOCS family proteins play a very important role in BRCA. SOCS3 may be a prognostic factor and SOCS2 may be a potential therapeutic target in breast cancer.

Protocatechualdehyde inhibits receptor activator of nuclear factor kappa-B ligand-induced osteoclastogenesis and attenuates lipopolysaccharide-induced inflammatory osteolysis.

Inflammatory osteolysis as a consequence of chronic bacterial infection underlies several lytic bone conditions, such as otitis media, osteomyelitis, septic arthritis, periodontitis, periprosthetic infection, and aseptic loosening of orthopedic implants. In consideration of the lack of effective preventive or treatments options against infectious osteolysis, the exploitation of novel pharmacological compounds/agents is critically required. The present study assessed the effect of protocatechualdehyde (PCA), a natural occurring polyphenolic compound with diverse biological activities including but not limited to antibacterial and antiinflammatory properties, on nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis in vitro and lipopolysaccharide (LPS)-induced bone loss in vivo. In the present study, it was found that PCA potently inhibited RANKL-induced osteoclast formation, fusion, and activation toward bone resorption in a dose-dependent manner via the suppression of the ERK/c-Fos/nuclear factor of activated T-cells, cytoplasmic 1 signaling axis. It was further demonstrated that the in vivo administration of PCA could effectively protect mice against the deleterious effects of LPS-induced calvarial bone destruction by attenuating osteoclast formation and activity in a dose-dependent manner. Collectively, these findings provided evidence for the potential therapeutic application of PCA in the prevention and treatment of infectious osteolytic conditions, and potentially other osteoclast-mediated bone diseases.

Asperolide A prevents bone metastatic breast cancer via the PI3K/AKT/mTOR/c-Fos/NFATc1 signaling pathway.

BACKGROUND: Breast cancer is the leading cause of death among women with malignant tumors worldwide. Bone metastasis is the main factor affecting the prognosis of breast cancer. Therefore, both antitumor and anti-breast-cancer-induced osteolysis agents are urgently needed. METHODS: We examined the effect of Asperolide A (AA), a marine-derived agent, on osteolysis and RANKL-induced phosphoinositide 3-kinase (PI3K)/AKT/mTOR/c-FOS/nuclear factor-activated T cell 1 (NFATc1) pathway activation, F-actin ring formation, and reactive oxygen species (ROS) generation in vitro. We evaluated AA effect on breast cancer MDA-MB-231 and MDA-MB-436 cells in vitro through CCK8 assay, wound healing assay, transwell assay, Annexin V-FITC/PI staining for cell apoptosis, and cell cycle assay. Furthermore, we assessed the effect of AA in vivo using a breast cancer-induced bone osteolysis nude mouse model, followed by micro-computed tomography, tartrate-resistant acid phosphatase staining, and hematoxylin and eosin staining. RESULTS: Asperolide A inhibited osteoclast formation and differentiation, bone resorption, F-actin belt formation, ROS activity, and osteoclast-specific gene and protein expressions and prevented PI3K/AKT/mTOR/c-FOS/NFATc1 signaling activation in a dose-dependent manner in vitro. AA also inhibited breast cancer growth and breast cancer-induced bone osteolysis by reducing osteoclast formation and function and inactivated PI3K/AKT/mTOR signaling in vivo. CONCLUSIONS: Our study demonstrated that AA suppressed bone metastatic breast cancer. These findings indicate AA as a potential, novel curative drug candidate for patients with bone metastatic breast cancer.

Racial/Ethnic Disparities and Survival in Pediatrics with Gliomas Based on the Surveillance, Epidemiology, and End Results Database in the United States.

BACKGROUND: Gliomas are the most common type of primary central nervous system tumor for both children and adults. However, the influence of racial/ethnic disparities on the survival of children with gliomas has not been fully evaluated yet. METHODS: Baseline characteristics of patients, including sex, year of diagnosis, surgery, grade, radiation, histology, and races, were collected. Univariate and multivariate analyses for overall survival (OS) were performed using Cox proportional hazards regression model. Survival curves were plotted using Kaplan-Meier methods. RESULTS: A total of 4400 childhood patients were enrolled, including 2516 non-Hispanic whites (NHWs), 1050 Hispanic whites (HWs), 519 blacks, 282 Asians or Pacific Islanders (APIs), and 33 American Indian/Alaska Natives. NHWs had the longest overall survival (OS), whereas blacks had the shortest OS (P = 0.003). Stratified by histologic type, OS of children with astrocytoma was better among NHWs and HWs than among blacks and APIs (P = 0.004). OS of children with ependymoma was better among NHWs and APIs than among HWs and blacks (P = 0.008). However, no significant difference was observed in OS for children with medulloblastoma (P = 0.854). CONCLUSIONS: Survival outcomes varied significantly by race/ethnicity among childhood gliomas. Better management of childhood gliomas is warranted to close the survival gap between race/ethnicity.

Consideration of Age Is Necessary for Increasing the Accuracy of the AJCC TNM Staging System of Pancreatic Neuroendocrine Tumors.

Purpose: Currently, of the two most common staging systems of pancreatic neuroendocrine tumors (pNETs) one is from the European Neuroendocrine Tumor Society (ENETS) and the other is from the American Joint Committee on Cancer (AJCC). However, there are imperfections in both these staging systems. Patients and methods: Patients were selected retrospectively from the Surveillance Epidemiology and End Results (SEER) database (2004 to 2013). The effect of age on the hazard ratio (HR) was evaluated using restricted cubic splines. The discriminatory power of the staging systems was determined using the concordance index (C-index). Results: A total of 3,034 patients with pNETs were included in the final analyses. The risk of death increased slowly along with age for patients under 60 years of age, but the risk of death rose sharply for those over 60 years of age, forming a mirrored L-shaped survival curve. In the current AJCC tumor-node-metastasis (TNM) staging system, no statistical significance was observed between stages IA and IB (p = 0.105). Patients with stage IIB even had longer OS than patients with IIA, although there was no statistical significance (p = 0.574). The proportion of stage III patients was small (2.7%). In the proposed aTNM staging system, significant survival differences could be observed among stage I, IIA, and IIB (p < 0.001) and the proportion of stage III rose from 2.7 to 25.7%. Conclusion: Our findings suggest that age has a critical influence on the survival of patients with pNETs. Age should be considered as a factor in future staging systems of pNETs.

Wentilactone A induces cell apoptosis by targeting AKR1C1 gene via the IGF-1R/IRS1/PI3K/AKT/Nrf2/FLIP/Caspase-3 signaling pathway in small cell lung cancer.

Wentilactone A (WA), a marine-derived compound, inhibits proliferation of NCI-H446, as demonstrated by previous research; however, the anti-SCLC mechanism underlying WA was not fully investigated. The present study aimed to investigate the anti-SCLC mechanism underlying WA in vitro and in vivo. Cell Counting Kit-8 was used to assay cell growth, flow cytometry was conducted to analyze cell apoptosis and nude mice xenografts were used to examine SCLC growth following WA treatment. Bioinformatics was used for verification of the target gene of WA. Reverse transcription-quantitative polymerase chain reaction and western blot were used to examine aldo-keto reductase family 1 member C1 (AKR1C1) mRNA and protein levels, and AKR1C1-associated proteins prior to and following WA treatment. Cell growth, apoptosis and growth of nude mice xenografts were assayed prior to and following transfection with AKR1C1 knockdown or overexpression carriers, respectively. It was determined that AKR1C1 was a target gene of WA. Decreased AKR1C1 expression and WA treatment promoted apoptosis in SCLC via the insulin like growth factor-1 receptor/insulin receptor substrate 1/phosphoinositide 3-kinase/AKT/nuclear factor-erythroid 2-associated factor 2/Fas-associated death domain-like interleukin-1-converting enzyme-like inhibitory protein/Caspase-3 pathway. WA attenuated the proliferation and induced the apoptosis of SCLC cells in vitro and in vivo by targeting the AKR1C1 gene. WA may be a novel AKR1C1-targeted drug candidate for the treatment of SCLC in the future.

High expression of AKR1C1 is associated with proliferation and migration of small-cell lung cancer cells.

AKR1C1 is a member of the AKR1C family, which not only plays an important role in hormone metabolism but is believed to be involved in carcinogen metabolism. Our previous study demonstrated that AKR1C1 was highly expressed in lung tumor tissues as compared with the tumor-adjacent tissues. Small-cell lung cancer (SCLC) is a special type of lung cancer. Surgical treatment of SCLC is usually difficult due to the high degree of malignancy and early metastasis, and difficulty in obtaining clinical specimens. There is not much basic or clinical research on SCLC in the People's Republic of China even in recent years. To investigate the mechanism of AKR1C1 in the pathogenesis of SCLC, the present study used H446 cell line to see whether AKR1C1 could affect the proliferation or migration of SCLC cells, and used a lentivirus to build the AKR1C1 overexpression and under-expression cell lines. The results indicated that AKR1C1 was an important inducement in the proliferation and migration of H446 cells. AKR1C1 promoted cell proliferation and played a vital role in the migration of SCLC cells. These results were also verified in nude mice in vivo. In conclusion, AKR1C1 plays an important role in the development and progression of SCLC and may represent an independent biomarker for assessment of the primary prognosis and therapy of SCLC.

Syntaxin 1A mediates isoflurane but not hypoxia preconditioning-induced alleviation of hypoxia-reoxygenation injury in rat cardiomyocytes.

Preconditioning with ischemia/hypoxia (IPC/HPC) or clinically available volatile anesthetics such as isoflurane (Iso-PC) could activate cardioprotective signaling pathways, thereby reducing myocardial ischemia/reperfusion (IR) injury. However, their molecular targets remain elusive. We herein investigated the roles of syntaxin 1A (Stx-1A) in cardiomyocyte protection induced by HPC and Iso-PC. Both in vivo myocardial IR model and in vitro cardiomyocyte hypoxia/reoxygenation (HR) model were used to test the effects of IR/HR, IPC/HPC and Iso-PC on Stx-1A protein expression. Stx-1A knockdown and overexpression in cardiomyocytes were achieved by adenovirus infection to define the relationship between Stx-1A levels and IPC/Iso-PC-induced cardioprotection. Cardiac troponin T (cTnT), cell apoptosis rate, and cell viability were introduced as indicators for cardiomyocyte HR injury. Changes of cardioprotective signaling pathways activities including PI3K/AKT/GSK3ß, ERK1/2, STAT3 and PKC were also detected using Western blot. Rat cardiomyocyte Stx-1A was upregulated 4 hours after IR or HR. IPC/HPC as well as Iso-PC further increased Stx-1A expression compared with IR/HR. Stx-1A knockdown was accompanied with more cell apoptosis and decreased cell viability while overexpression of Stx-1A seemed cardioprotective. Iso-PC induced decrease in cell apoptosis and increase in cell viability but not HPC-induced cardioprotection was reversed by Stx-1A shRNA transfection. No difference in cell apoptosis or cell viability was found before and after Stx-1A overexpression in each group. Moreover, Stx-1A knockdown were accompanied with increased PI3K/AKT/GSK3ß activities irrespective of the treatments. Stx-1A is cardioprotective and a potential target of isoflurane induced cardioprotection. Further studies are needed to test whether stx-1A is regulated by AKT/GSK3ß signaling.

Bisthiodiketopiperazines and Acorane Sesquiterpenes Produced by the Marine-Derived Fungus Penicillium adametzioides AS-53 on Different Culture Media.

Chemical investigation of the marine-sponge-derived fungus Penicillium adametzioides AS-53 resulted in the identification of two new bisthiodiketopiperazine derivatives, adametizines A (1) and B (2), from cultivation in a liquid potato-dextrose broth (PDB) culture medium, whereas two new acorane sesquiterpenes, adametacorenols A (3) and B (4), were isolated from a rice solid culture medium. The structures of these compounds were elucidated on the basis of spectroscopic analysis. The absolute configuration of compound 1 was determined by X-ray crystallographic analysis, and that of 3 was determined by modified Mosher's method. Compound 1 exhibited lethality against brine shrimp (Artemia salina) with an LD50 value of 4.8 µM and inhibitory activities against Staphyloccocus aureus, Aeromonas hydrophilia, Vibrio spp. V. harveyi and V. parahaemolyticus, and Gaeumannomyces graminis with minimum inhibitory concentration values of 8, 8, 32, 8, and 16 µg/mL, respectively. Chlorination at C-7 significantly increased the brine shrimp lethality and antimicrobial activity of the bisthiodiketopiperazines.

Ophiobolin O isolated from Aspergillus ustus induces G1 arrest of MCF-7 cells through interaction with AKT/GSK3ß/cyclin D1 signaling.

Ophiobolin O is a member of ophiobolin family, which has been proved to be a potent anti-tumor drug candidate for human breast cancer. However, the anti-tumor effect and the mechanism of ophiobolin O remain unclear. In this study, we further verified ophiobolin O-induced G1 phase arrest in human breast cancer MCF-7 cells, and found that ophiobolin O reduced the phosphorylation level of AKT and GSK3ß, and induced down-regulation of cyclin D1. The inverse docking (INVDOCK) analysis indicated that ophiobolin O could bind to GSK3ß, and GSK3ß knockdown abolished cyclin D1 degradation and G1 phase arrest. Pre-treatment with phosphatase inhibitor sodium or thovanadate halted dephosphorylation of AKT and GSK3ß, and blocked ophiobolin O-induced G1 phase arrest. These data suggest that ophiobolin O may induce G1 arrest in MCF-7 cells through interaction with AKT/GSK3ß/cyclin D1 signaling. In vivo, ophiobolin O suppressed tumor growth and showed little toxicity in mouse xenograft models. Overall, these findings provide theoretical basis for the therapeutic use of ophiobolin O.

Brocazines A-F, Cytotoxic Bisthiodiketopiperazine Derivatives from Penicillium brocae MA-231, an Endophytic Fungus Derived from the Marine Mangrove Plant Avicennia marina.

Six new disulfide-bridged diketopiperazine derivatives, brocazines A-F (1-6), along with one known analogue (7), were isolated and identified from the cytotoxic extract of Penicillium brocae MA-231, a fungus obtained from the fresh tissue of the marine mangrove plant Avicennia marina. The structures of these compounds were established on the basis of detailed interpretation of NMR and mass spectroscopic data. X-ray crystallographic analysis confirmed the structure of 1 and established the structure and absolute configuration of 5, while the absolute configurations for compounds 1, 4, and 6 were deduced by comparison of the CD data with those of 5. Compounds 1, 2, 5, and 6 showed cytotoxic activities against several tumor cell lines.

Sulfur-containing cytotoxic curvularin macrolides from Penicillium sumatrense MA-92, a fungus obtained from the rhizosphere of the mangrove Lumnitzera racemosa.

Sumalarins A-C (1-3), the new and rare examples of sulfur-containing curvularin derivatives, along with three known analogues (4-6), were isolated and identified from the cytotoxic extract of Penicillium sumatrense MA-92, a fungus obtained from the rhizosphere of the mangrove Lumnitzera racemosa . Their structures were established by detailed interpretation of NMR and MS data, and compound 1 was confirmed by X-ray crystallographic analysis. Compounds 1-3 and 5 showed potent cytotoxicity against some of the tested tumor cell lines. Sulfur substitution at C-11 or a double bond at C-10 significantly increased the cytotoxic activities of the curvularin analogues.

Ophiobolin-O reverses adriamycin resistance via cell cycle arrest and apoptosis sensitization in adriamycin-resistant human breast carcinoma (MCF-7/ADR) cells.

Multidrug-resistance is a major obstacle facing cancer chemotherapy. This paper demonstrates that novel compound Ophiobolin-O reverses MCF-7/ADR resistance to adriamycin (ADM). The IC50 of ADM treated MCF-7 cells was 2.02 ± 0.05 µM and 74.00 ± 0.18 µM treated MCF-7/ADR cells, about 37-fold, compared to the former. However, 0.1 µM Ophiobolin-O (less than 20% inhibition concentration) combined with ADM caused the decreased IC50 of ADM to 6.67 ± 0.98 µM, indicating it reversed ADM resistance of MCF-7/ADR cells (11-fold). Furthermore, Ophiobolin-O increased ADM-induced mitochondrial pathway apoptosis and G2/M phase arrest, which is partly due to the elevation level of ROS in MCF-7/ADR cells. As we described in this paper, the reversal effect of Ophiobolin-O may be due to the reduction of resistance-related protein P-Glycoprotein (P-gp, also known as MDR1) through inhibiting the activity of the multidrug resistance 1 (MDR1) gene promoter, which makes MCF-7/ADR cells more sensitive to ADM treatment. Assays in nude mice also showed that the combination of ADM and Ophiobolin-O significantly improved the effect of ADM.

Asperolide A, a marine-derived tetranorditerpenoid, induces G2/M arrest in human NCI-H460 lung carcinoma cells, is mediated by p53-p21 stabilization and modulated by Ras/Raf/MEK/ERK signaling pathway.

Here we first demonstrate that asperolide A, a very recently reported marine-derived tetranorditerpenoid, leads to the inhibition of NCI-H460 lung carcinoma cell proliferation by G2/M arrest with the activation of the Ras/Raf/MEK/ERK signaling and p53-dependent p21 pathway. Treatment with 35 µM asperolide A (2 × IC(50)) resulted in a significant increase in the proportion of G2/M phase cells, about a 2.9-fold increase during 48 h. Immunoblot assays demonstrated time-dependent inhibition of G2/M regulatory proteins. Moreover, asperolide A significantly activated MAP kinases (ERK1/2, JNK and p38 MAP kinase) by phosphorylation, and only the inhibition of ERK activation by PD98059 reversed downregulation of G2/M regulatory proteins CDC2, and suppressed upregulation of p21 and p-p53 levels. Transfection of cells with dominant-negative Ras (RasN17) mutant genes up-regulated asperolide A-induced the decrease of cyclin B1 and CDC2, suppressed Raf, ERK activity and p53-p21 expression, and at last, abolished G2/M arrest. This study indicates that asperolide A-induced G2/M arrest in human NCI-H460 lung carcinoma cells relys on the participation of the Ras/Raf/MEK/ERK signaling pathway in p53-p21 stabilization. An in vivo study with asperolide A illustrated a marked inhibition of tumor growth, and little toxcity compared to Cisplatin therapy. Overall, these findings provide potential effectiveness and a theoretical basis for the therapeutic use of asperolide A in the treatment of malignancies.

Wentilactone B from Aspergillus wentii induces apoptosis and inhibits proliferation and migration of human hepatoma SMMC-7721 cells.

Wentilactone B (EN-48-57) is one of the six derivatives separated from Aspergillus wentii (EN-48). Of these derivatives, Wentilactone B exerted a more significant antibacterial and cytotoxic activity in several tumor cell lines. The present study demonstrates that Wentilactone B could efficiently induce SMMC-7721 cells apoptosis, but not normal hepatic cells, as measured by an inverted microscope, 4',6-diamidino-2-phenylindole staining and flow cytometry. In addition, Wentilactone B could inhibit the metastasis of SMMC-7721 cells, which was detected by colony formation, scratch migration and a transwell assay, and could induce a series of intracellular events, including the down-regulation of CD44 and epidermal growth factor receptor proteins. In conclusion, Wentilactone B inhibited the growth of SMMC-7721 cells by triggering apoptosis and inhibiting metastasis.