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Extracellular signal-regulated protein kinase 1/2 (ERK1/2), the only known substrate of MEK1/2, is located downstream of the RAS-RAF-MEK-ERK (MAPK) pathway and is associated with the abnormal activation and poor prognosis of cancer. To date, several small-molecule inhibitors of RAS, RAF, and MEK have been reported to make rapid advances in cancer therapy; however, acquired resistance still occurs, thereby weakening the therapeutic efficacy of these inhibitors. Recently, selective inhibition of ERK1/2 has been regarded as a potential cancer therapeutic strategy that can not only effectively block the MAPK pathway but also overcome drug resistance caused by upstream mutations in

Autophagy, an evolutionarily highly conserved cellular degradation process, plays the Janus role (either cytoprotective or death-promoting) in colorectal cancer, so the targeting of several key autophagic pathways with small-molecule compounds may be a new therapeutic strategy. In this review, we discuss autophagy-associated cell death pathways and key cytoprotective autophagy pathways in colorectal cancer. Moreover, we summarize a series of small-molecule compounds that have the potential to modulate autophagy-associated cell death or cytoprotective autophagy for therapeutic purposes. Taken together, these findings demonstrate the Janus role of autophagy in colorectal cancer, and shed new light on the exploitation of a growing number of small-molecule compounds to target autophagy in future cancer drug discovery.

Hepatitis B virus (HBV) infection is a worldwide health problem, and chronic infection can cause many diseases ranging from liver fibrosis to hepatocellular carcinoma (HCC) by complicated mechanisms. Currently, the treatment of HBV infection mainly depends on interferons (IFNs) and nucleotide analogues (NAs); however, both have some limitations. In 2012, sodium taurocholate cotransporting polypeptide (NTCP) was identified as the entry receptor of HBV. Based upon this groundbreaking discovery, a series of molecules have been gradually developed and evaluated to discover novel entry inhibitors targeting NTCP. However, only two macromolecules have been used for potential clinical applications so far. In this Perspective, we focus on summarizing the structural features that convey the biological functions of NTCP, as well as further discuss the anti-HBV activity and selectivity of inhibitors in HBV-related diseases, which should provide clues in the future for the discovery of drug candidates targeting NTCP.

Two new alkaloids, peniokaramine (1) and penipyranopyridine (6), along with seven known compounds, were isolated from the marine-derived fungus Penicillium sp. LSH-3-1. Their structures were elucidated from UV, IR, MS, 1D and 2D NMR spectroscopic data. The anti-inflammatory potential of compounds 1-8 in LPS-induced RAW264.7 cells was detected, revealing that compounds 3 and 5 significantly decreased LPS-induced production of pro-inflammatory mediators, including NO, IL-6 and TNF-α. Compounds 1-8 were also screened for their cytotoxic activity against A549 cells and compound 1 showed moderate activity.

Long non-coding RNAs (lncRNAs), a type of transcriptional products with more than 200 nucleotides in length, have been less characterized compared to protein-coding RNAs so far. However, it is increasingly evident that lncRNAs are key players involved in multiple genetic and epigenetic activities during the carcinogenesis of neoplastic diseases. Currently, accumulating data have pointed out the close connection between lncRNAs and esophageal carcinoma (EC), shedding light on further unravelling the complexity of lncRNAs and EC. Methods In this review, we thoroughly collect the evidence regarding original studies on EC-related lncRNAs by searching in MEDLINE/PubMed, Embase and WOS/SCI. We especially focus on summarizing EC-related lncRNAs based upon more updated evidence, and further discuss their different features from various perspectives, including regulatory mechanisms, functional roles in cancer hallmarks, as well as potential diagnostic and therapeutic applications, which would together reveal the complexity of lncRNAs and EC for potential clinical applications. Results We discuss over thirty EC-related lncRNAs in total, most of which function as oncogenes that promote cancer development, while the others function as tumor suppressors. Regulatory mechanisms included sponging miRNAs, direct interaction with proteins, and exosome visicle-based intercellular communication. Based upon these modes of actions, lncRNAs play multiple roles in cancer hallmarks such as uncontrolled cell growth, evasion of programmed cell death, invasion and metastasis. Moreover, lncRNAs packaged in exosomes have unique potency to serve as diagnostic biomarkers; some lncRNAs show great potential to predict patients' chemical resistance and may be crucial targets to improve chemoradiotherapy and targeted therapy. Conclusion Over the past few years, the research of EC-related lncRNAs maintain obviously rapid development, yet further exploration of exact mechanisms and clinical applications that lncRNAs can offer need to be done. Indeed, LncRNAs hold the promise of being applied in multiple clinical scenarios, especially early diagnosis of EC, improvement of sensitivity to chemotherapy/radiotherapy, and development of small-molecule targeted drugs.

Citrullus colocynthis (CC), an ethnic medicine, distributed in Xinjiang Uygur Autonomous Region of China, is a traditional remedy for rheumatic arthritis or diseases caused by abnormal black biliary. Here, we investigated the therapeutic effect of CC on Parkinson's disease (PD) and its protective mechanisms. Firstly, the effects of CC on MPTP-induced PD mouse model were evaluated by a series of behavioral tests. Significant improvement of bradykinesia and memory reduction and reduction of climbing time were observed. Meanwhile, improvement of tyrosine hydroxylase (TH) and α-synuclein was also detected by immunohistochemical and western blot analysis. Additionally, it was also found that CC could relieve the oxidative stress in PD mouse brain tissues by decreasing activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and increasing activity of malondialdehyde (MDA). Moreover, possible protective mechanisms were analyzed by a set of combined bioinformatics methods. Subsequently, the mechanism was verified using immunofluorescence, flow cytometry and western blot. Results showed that CC could reduce oxidative damage by inhibiting the autophagy via ROS-AMPK-ULK1 signaling pathway in MPP+-induced SH-SY5Y cells. In conclusion, the present study validated that CC has a promising neuroprotective effect against PD, which can reduce oxidative stress and inhibiting autophagic cell death.

The family with sequence similarity 20, member C (Fam20C), a Golgi casein kinase, has been recently regarded as a potential therapeutic target for the treatment of triple negative breast cancer (TNBC). Lacking enzyme activity center has been becoming an obstacle to the development of small-molecule inhibitors of Fam20C. Herein, we combined in silico high-throughput screening with chemical synthesis methods to obtain a new small-molecule Fam20C inhibitor 3r, which exhibited desired anti-proliferative activities against MDA-MB-231 cells and also inhibited migration. Subsequently, the enzymatic assay, molecular docking, and molecular dynamics (MD) simulations were carried out for validating that 3r could bind to Fam20C. In addition, 3r was found to induce apoptosis via the mitochondrial pathway in MDA-MB-231 cells as well as to inhibit cell migration. Moreover, we demonstrated that 3r inhibited tumor growth in vivo and thereby having a good therapeutic potential on TNBC. Taken together, these results suggest that 3r may be a novel Fam20C inhibitor with anti-proliferative and apoptosis-inducing activities, which would shed light on discovering more small-molecule drugs for the future TNBC therapy.

Co-occurring microorganisms have been proved to influence the performance of each other by metabolic means in nature. Here we generated a synthetic fungal-bacterial community comprising Penicillium citrinum and Pseudomonas aeruginosa employing the previously described membrane-separated co-culture device. By applying a newly designed molecular networking routine, new citrinin-related metabolites induced by the fungal-bacterial cross-talk were unveiled in trace amounts. A mechanically cycled co-culture setup with external pumping forces accelerating the chemically interspecies communication was then developed to boost the production of cross-talk-induced metabolites. Multivariate data analysis combined with molecular networking revealed the accumulation of a pair of co-culture-induced molecules whose productions were positively correlated to the exchange rate in the new co-cultures, facilitating the discovery of the previously undescribed antibiotic citrinolide with a novel skeleton. This highly oxidized citrinin adduct showed significantly enhanced antibiotic property against the partner strain P. aeruginosa than its precursor citrinin, suggesting a role in the microbial competition. Thus, we propose competitive-advantage-oriented structural modification driven by microbial defence response mechanism in the interspecies cross-talk might be a promising approach in the search for novel antibiotics. Besides, this study highlights the utility of MS-based metabolomics as an effective tool in the direct biochemical analysis of the community metabolism.

The evaluation of herbicidal activity and the isolation of plant allelopathic substances can lead to the discovery of new herbicide. This study has confirmed that the ethanol extract of S. mukorossi leaves was inhibitory to growth of Avena fatua L. and Amaranthus retroflexus L. both in petri dish experiment and pot culture assay, with the fresh weight inhibition varied between 47.60% and 62.05% at a concentration of 40 g/L of the leaf extract, being comparable to that of a commercialized natural product herbicide pelargonic acid at a concentration of 4 g/L. Five herbicidal compounds, oleanolic acid (1), lupeol (2), d-pinitol (3), hexadecanoic acid (4) and octadecanoic acid (5) were isolated from the most active fraction, petroleum ether extract. D-pinitol (3) showed the highest growth inhibitory activity against both the shoot and root of A. fatua, with the half maximal inhibitory concentration (IC50) values of 53.61 and 56.43 μg/mL, respectively. Furthermore, oleanolic acid (1) and d-pinitol (3) also inhibited the growth of A. retroflexus with the IC50 value of 56.05 and 61.89 μg/mL against shoot growth, and 58.07 and 66.70 μg/mL against root growth, respectively. Thus, oleanolic acid (1) and d-pinitol (3) are the main phytotoxin constituents of S. mukorossi, and these compounds have the potential for further development as a botanical herbicide.

UNC-51-like kinase 1 (ULK1), the yeast Atg1 ortholog, is the sole serine-threonine kinase and initiating enzyme in autophagy, which may be regarded as a target in Parkinson's disease (PD). Herein, we discovered a small molecule 33i (BL-918) as a potent activator of ULK1 by structure-based drug design. Subsequently, some key amino acid residues (Arg18, Lys50, Asn86, and Tyr89) were found to be crucial to the binding pocket between ULK1 and 33i by site-directed mutagenesis. Moreover, we found that 33i induced autophagy via the ULK complex in SH-SY5Y cells. Intriguingly, this activator displayed a cytoprotective effect on MPP+-treated SH-SY5Y cells, as well as protected against MPTP-induced motor dysfunction and loss of dopaminergic neurons by targeting ULK1-modulated autophagy in mouse models of PD. Together, these results demonstrate the therapeutic potential to target ULK1, and 33i, the novel activator of ULK1, may serve as a candidate drug for future PD treatment.

Hepatitis B virus (HBV) infections affect about 240 million patients worldwide and increase the risk of liver cirrhosis and hepatocellular carcinoma. It is estimated that about 686 thousand people died annually of liver damage resulted from HBV infections. At present, two classes of antiviral drugs have been approved by the Food and Drug Administration (FDA) for the treatment of hepatitis B, immunomodulators (interferon [IFN]-a and pegylated-interferon [PEG-IFN]-a) and nucleos(t)ide analogs (lamivudine, telbivudine, adefovir, tenofovir [TDF], and entecavir [ETV]). However, it still remains a daunting challenge for curing HBV, because of the low sustained response rates (20-30%) and many side effects of IFN and peg-IFN. Although nucleoside analogues are well tolerated and exhibit an early and potent antiviral effect, the selection of resistant mutants and nephrotoxicity during long-term therapy limit their use. Here, we focus on summarizing the currently approved anti-HBV drugs and characterization of novel HBV inhibitors and analysing their structures, targets, anti-HBV effects and mechanisms of action, which may shed new light on the discovery of small compounds as potential anti-HBV drugs for treatment of HBV.

Upon the basis of The Cancer Genome Atlas (TCGA) data set, we identified that several autophagy-related proteins such as AMP-activated protein kinase (AMPK) were remarkably downregulated in breast cancer. Combined with coimmunoprecipitation assay, we demonstrated that BRD4 might interact with AMPK. After analyses of the pharmacophore and WPF interaction optimization, we designed a small-molecule inhibitor of BRD4, 9f (FL-411) which was validated by cocrystal structure with BD1 of BRD4. Subsequently, 9f was discovered to induce ATG5-dependent autophagy-associated cell death (ACD) by blocking BRD4-AMPK interaction and thus activating AMPK-mTOR-ULK1-modulated autophagic pathway in breast cancer cells. Interestingly, the iTRAQ-based proteomics analyses revealed that 9f induced ACD pathways involved in HMGB1, VDAC1/2, and eEF2. Moreover, 9f displayed a therapeutic potential on both breast cancer xenograft mouse and zebrafish models. Together, these results demonstrate that a novel small-molecule inhibitor of BRD4 induces BRD4-AMPK-modulated ACD in breast cancer, which may provide a candidate drug for future cancer therapy.

// Yujuan Chen 1, * , Xiaoyun Wang 1, * , Chuan Cao 2 , Xiaodong Wang 1 , Shufang Liang 1 , Cheng Peng 2 , Leilei Fu 1 and Gu He 1 1 State Key Laboratory of Biotherapy and Department of Breast Surgery, West China Hospital, West China Medical School, Sichuan University and Collaborative Innovation Center for Biotherapy, Chengdu 610041, China 2 State Key Laboratory Breeding Base of Systematic Research Development and Utilization of Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, China * These authors have contributed equally to this work Correspondence to: Xiaodong Wang, email: wxd65112@163.com Leilei Fu, email: leilei_fu@163.com Gu He, email: hegu@scu.edu.cn Keywords: breast cancer; Raf; ERK; HSP90; apoptosis Received: August 09, 2017 Accepted: September 22, 2017 Published: October 26, 2017 ABSTRACT Raf and extracellular signal-regulated kinases (ERK) are both important therapeutic targets in the mitogen-activated protein kinase (MAPK) pathway, and play crucial roles in the apoptosis resistance of breast cancer cells. In the present study, cytotoxic and apoptosis-inducing activities of the Raf/ERK dual inhibitor CY-9d were found to be restricted in triple negative breast cancer (TNBC) cells compared with ER/PR-positive cells. Based on the analysis of differentially expressed proteins using a quantitative proteomic iTRAQ method and bioinformatics analysis, HSP90 was found to identify as a potential mediator between Raf and ERK in TNBC cells. Western blotting and RNA interference suggested that down-regulated IQGAP1 can attenuate the routine Raf/MEK/ERK cascade and recruit HSP90 as a bypass pathway. Simultaneous treatment with the HSP90 inhibitor and CY-9d at sub-therapeutic doses was found to produce synergistic therapeutic and apoptosis-inducing effects in TNBC cells. Moreover, CY-9d was also found to suppress breast cancer growth, inhibit the activation of Raf/ERK, and induce mitochondrial apoptosis in vivo without remarkable toxicity. These results support the combination of HSP90 and Raf/ERK inhibitors as a potential target therapeutic strategy with enhanced tumor growth suppression, downstream pathway blockade, and greater induction of apoptosis.

ERK1 and ERK5 are proposed to have pivotal roles in several types of cancer. Under some circumstance, ERK5 may provide a common bypass route, which rescues proliferation upon abrogation of ERK1 signaling. Thus, we accurately classified the tumor types from The Cancer Genome Atlas (TCGA) based on the expression levels of ERK1 and ERK5. We proposed a novel therapeutic strategy to overcome the above-mentioned compensatory mechanism in specific tumor types by co-targeting both ERK1 and ERK5. On the basis of the idea of overcoming ERK5 compensation mechanism, 22ac (ADTL-EI1712) as the first selective dual-target inhibitor of ERK1 and ERK5 was discovered to have potent antitumor effects in vitro and in vivo. Interestingly, this compound was found to induce regulated cell death accompanied by autophagy in MKN-74 cells. Taken together, our results warrant the potential of this dual-target inhibitor as a new candidate drug that conquers compensatory mechanism in certain tumor types.

Eukaryotic elongation factor 2 kinase (eEF2K) is a key α-kinase that negatively regulates the extension step of protein synthesis, which consumes most of the energy and amino acids required for protein synthesis. Studies have found that eEF2K protein is related to the breast cancer. However, existing inhibitor effect has not achieved the desired effect in cancer therapy. Proteolysis target chimeric (PROTAC) technology is uses proteasome to degrade target protein to achieve the purpose of inhibiting tumour cell growth. Here, we reported that the use of PROTAC strategy in combining with star eEF2K inhibitor A484954 and its potential derivatives. Consequently, candidate compound 11l was found to degrade eEF2K and induce apoptosis in human breast carcinoma MDA-MB-231 cells. Together, these findings demonstrate that our eEF2K-targeting PROTAC small molecule would be a potential new strategy for future breast cancer therapy.

A prototype of gecko-inspired wall-climbing robot based on vibration suction mechanism is proposed. The robot adheres to the wall surface based on a novel negative pressure technology named as vibration suction. According to the theory of vibration suction, the vibration suction module is designed as the foot of the wall-climbing robot. In addition, the tripod gait of geckos is taken into account in the motion planning of the robot. By combining the unique properties of vibration suction mechanism and the tripod gait of the geckos, several advantages including stable motion, certain load capacity, anti-overturning ability, and good suction force to the wall surfaces are obtained. The climbing ability is verified by the experiment on the surface of the glass, which manifests that the robot can climb vertically at the highest speed of 13.75 mm/s with a spot turning at the single maximum turning angle of 20°. Potential applications of this proposed climbing robot in some fields include repair, construction, cleaning, and exploration.

Sodium taurocholate cotransport polypeptide (NTCP) plays an important role in the development of hepatitis and acts as a switch to allow hepatitis virus to enter hepatic cells. As the entry receptor protein of hepatitis virus, NTCP is also an effective target for the treatment of hepatocellular carcinoma. Herein, twenty-five benzamide analogues were synthesized based on the virtual screening design and their anti-proliferative activities against HepG2 cells were evaluated in vitro. Compound 35 was found to be promising, with an IC50 value of 2.8 μM. The apoptosis induced by 35 was characterized by the regulation of markers, including an increase in Bax, cleaved-caspase 3, and cleaved-PARP proteins, and a decrease in Bcl-2 protein. Molecular docking and molecular dynamics (MD) simulation confirmed that compound 35 can bind tightly to NTCP. Western blot analysis also showed that NTCP was inhibited. Altogether, these results indicate that compound 35 acts as a novel NTCP inhibitor to induce apoptosis in HepG2 cells.

UNC-51-like kinase 1 (ULK1) is well-known to initiate autophagy, and the downregulation of ULK1 has been found in most breast cancer tissues. Thus, the activation of ULK1-modulated autophagy could be a promising strategy for breast cancer therapy. In this study, we found that ULK1 was remarkably downregulated in breast cancer tissue samples by The Cancer Genome Atlas (TCGA) analysis and tissue microarray (TMA) analysis, especially in triple negative breast cancer (TNBC). To design a ULK1 agonist, we integrated in silico screening and chemical synthesis to acquire a series of small molecule candidates. After rounds of kinase and anti-proliferative activity screening, we discovered the small molecule, LYN-1604, to be the best candidate for a ULK1 agonist. Additionally, we identified that three amino acid residues (LYS50, LEU53, and TYR89) were key to the activation site of LYN-1604 and ULK1 by site-directed mutagenesis and biochemical assays. Subsequently, we demonstrated that LYN-1604 could induce cell death, associated with autophagy by the ULK complex (ULK1-mATG13-FIP200-ATG101) in MDA-MB-231 cells. To further explore LYN-1604-induced autophagic mechanisms, we found some potential ULK1 interactors, such as ATF3, RAD21, and caspase3, by performing comparative microarray analysis. Intriguingly, we found that LYN-1604 induced cell death involved in ATF3, RAD21, and caspase3, accompanied by autophagy and apoptosis. Moreover, we demonstrated that LYN-1604 has potential for good therapeutic effects on TNBC by targeting ULK1-modulated cell death in vivo; thus making this ULK1 agonist a novel potential small-molecule drug candidate for future TNBC therapy.

Sophora flavescens alkaloids (SFA), a promising botanical pesticide, have been registered and commercialized in China. In this study, we attempted to investigate the effect of SFA on the growth and development of tomatoes. Tomato seedlings were exposed to SFA at three dosages: 333.0, 166.5 and 111.0 mg L −1 . The morphological and physiological responses were recorded after spraying during the vegetative period, and yield and fruit quality after spraying during the reproductive period. SFA treatment increased the height and stem diameter of the seedlings as well as having a positive effect on almost all physiological leaf characteristics. Early yield and fruit quality were also improved. These findings suggest that the application of SFA has a favorable effect on the growth and yield of tomatoes, improving overall quality and antioxidative performance.

Cancer is a deadly disease with increasing incidence and mortality rates and affects the life quality of millions of people per year. The past 15 years have witnessed the rapid development of targeted therapy for cancer treatment, with numerous anticancer drugs, drug targets and related gene mutations been identified. The demand for better anticancer drugs and the advances in database technologies have propelled the development of databases related to anticancer drugs. These databases provide systematic collections of integrative information either directly on anticancer drugs or on a specific type of anticancer drugs with their own emphases on different aspects, such as drug-target interactions, the relationship between mutations in drug targets and drug resistance/sensitivity, drug-drug interactions, natural products with anticancer activity, anticancer peptides, synthetic lethality pairs and histone deacetylase inhibitors. We focus on a holistic view of the current situation and future usage of databases related to anticancer drugs and further discuss their strengths and weaknesses, in the hope of facilitating the discovery of new anticancer drugs with better clinical outcomes.

Signet-ring cell carcinoma (SRCC) has specific epidemiology and oncogenesis in gastric cancer, however, with no systematical investigation for prognostic genomic features. Here we report a systematic investigation conducted in 1868 Chinese gastric cancer patients indicating that signet-ring cells content was related to multiple clinical characteristics and treatment outcomes. We thus perform whole-genome sequencing on 32 pairs of SRC samples, and identify frequent CLDN18-ARHGAP26/6 fusion (25%). With 797 additional patients for validation, prevalence of CLDN18-ARHGAP26/6 fusion is noticed to be associated with signet-ring cell content, age at diagnosis, female/male ratio, and TNM stage. Importantly, patients with CLDN18-ARHGAP26/6 fusion have worse survival outcomes, and get no benefit from oxaliplatin/fluoropyrimidines-based chemotherapy, which is consistent with the fact of chemo-drug resistance acquired in CLDN18-ARHGAP26 introduced cell lines. Overall, this study provides insights into the clinical and genomic features of SRCC, and highlights the importance of frequent CLDN18-ARHGAP26/6 fusions in chemotherapy response for SRCC., Signet-ring cell carcinoma (SRCC) is a unique type of gastric cancer with no prognostic features. Here, the authors report a CLDN18-ARHGAP26/6 gene fusion in patients with a high signet-ring cell content, poor survival outcomes, and who experience no benefit from platinum/fluoropyrimidines-based chemotherapy.

Co-occurring microorganisms have been proved to influence the performance of each other by metabolic means in nature. Here we generated a synthetic fungal-bacterial community comprising Penicillium citrinum and Pseudomonas aeruginosa employing the previously described membrane-separated co-culture device. By applying a newly designed molecular networking routine, new citrinin-related metabolites induced by the fungal-bacterial cross-talk were unveiled in trace amounts. A mechanically cycled co-culture setup with external pumping forces accelerating the chemically interspecies communication was then developed to boost the production of cross-talk-induced metabolites. Multivariate data analysis combined with molecular networking revealed the accumulation of a pair of co-culture-induced molecules whose productions were positively correlated to the exchange rate in the new co-cultures, facilitating the discovery of the previously undescribed antibiotic citrinolide with a novel skeleton. This highly oxidized citrinin adduct showed significantly enhanced antibiotic property against the partner strain P. aeruginosa than its precursor citrinin, suggesting a role in the microbial competition. Thus, we propose competitive-advantage-oriented structural modification driven by microbial defence response mechanism in the interspecies cross-talk might be a promising approach in the search for novel antibiotics. Besides, this study highlights the utility of MS-based metabolomics as an effective tool in the direct biochemical analysis of the community metabolism.

// Lei-lei Fu 1,* , Mao Tian 1,* , Xiang Li 1,* , Jing-jing Li 1 , Jian Huang 2 , Liang Ouyang 1 , Yonghui Zhang 1,3 and Bo Liu 1 1 State Key Laboratory of Biotherapy, Collaborative Innovation Center of Biotherapy, Department of Urology, West China Hospital, Sichuan University, Chengdu, China 2 School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, China 3 Collaborative Innovation Center for Biotherapy, Department of Pharmacology & Pharmaceutical Sciences, School of Medicine, Tsinghua University, Beijing, China * These authors contributed equally to this work Correspondence to: Bo Liu, email: // Jian Huang, email: // Keywords : bromodomain, BRD2/4, BRD3, BRDT, BET inhibitor Received : January 22, 2015 Accepted : February 13, 2015 Published : March 12, 2015 Abstract As a conserved protein interaction module that recognizes and binds to acetylated lysine, bromodomain (BRD) contains a deep, largely hydrophobic acetyl lysine binding site. Proteins that share the feature of containing two BRDs and an extra-terminal domain belong to BET family, including BRD2, BRD3, BRD4 and BRDT. BET family proteins perform transcription regulatory function under normal conditions, while in cancer, they regulate transcription of several oncogenes, such as c-Myc and Bcl-2. Thus, targeting BET proteins may be a promising strategy, and intense interest of BET proteins has fueled the development of structure-based bromodomain inhibitors in cancer. In this review, we focus on summarizing several small-molecule BET inhibitors and their relevant anti-tumor mechanisms, which would provide a clue for exploiting new targeted BET inhibitors in the future cancer therapy.

The aim of this study was to discover a small molecule activator BL-AD008 targeting AMPK/ZIPK and inducing apoptosis in cervical cancer. In this study, we systematically constructed the global protein-protein interaction (PPI) network and predicted apoptosis-related protein connections by the Naïve Bayesian model. Then, we identified some classical apoptotic PPIs and other previously unrecognized PPIs between apoptotic kinases, such as AMPK and ZIPK. Subsequently, we screened a series of candidate compounds targeting AMPK/ZIPK, synthesized some compounds and eventually discovered a novel dual-target activator (BL-AD008). Moreover, we found BL-AD008 bear remarkable anti-proliferative activities toward cervical cancer cells and could induce apoptosis by death-receptor and mitochondrial pathways. Additionally, we found that BL-AD008-induced apoptosis was affected by the combination of AMPK and ZIPK. Then, we found that BL-AD008 bear its anti-tumor activities and induced apoptosis by targeting AMPK/ZIPK in vivo. In conclusion, these results demonstrate the ability of systems biology network to identify some key apoptotic kinase targets AMPK and ZIPK; thus providing a dual-target small molecule activator (BL-AD008) as a potential new apoptosis-modulating drug in future cervical cancer therapy.

// Bo Liu 1 , Leilei Fu 1 , Cui Zhang 2 , Lan Zhang 2 , Yonghui Zhang 1, 3 , Liang Ouyang 1 , Gu He 1 , Jian Huang 2 1 State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China 2 School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, China 3 Collaborative Innovation Center for Biotherapy, Department of Pharmacology & Pharmaceutical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China Correspondence to: Liang Ouyang, e-mail: ouyangliang@scu.edu.cn Gu He, e-mail: heguscu@163.com Jian Huang, e-mail: 13504051049@163.com Keywords: Extracellular signal-regulated kinase 1/2 (ERK1/2), ERK inhibitor (BL-EI001), Apoptosis, Mitochondrial pathway, Breast cancer Received: December 31, 2014 Accepted: January 08, 2015 Published: January 27, 2015 ABSTRACT Extracellular signal-regulated kinase1/2 (ERK1/2) plays a crucial role in the resistance of apoptosis in carcinogenesis; however, its targeted small-molecule inhibitors still remain to be discovered. Thus, in this study, we computationally and experimentally screened a series of small-molecule inhibitors targeting ERK toward different types of human breast cancer cells. Subsequently, we synthesized some candidate ERK inhibitors, identified a novel ERK inhibitor (BL-EI001) with anti-proliferative activities, and analyzed the BL-EI001/ERK complex. Moreover, we found that BL-EI001 induced breast cancer cell apoptosis via mitochondrial pathway but independent on Ras/Raf/MEK pathway. In addition, we carried out proteomics analyses for exploring some possible BL-EI001-induced apoptotic pathways, and further found that BL-EI001-induced apoptosis affected ERK phosphorylation in breast cancer. Further, we found that BL-EI001 bear anti-tumor activities without remarkable toxicities, and also induced mitochondrial apoptosis by targeting ERK in vivo . Taken together, these results demonstrate that in silico design and experimental discovery of a synthesized small-molecule ERK inhibitor (BL-EI001)as a potential novel apoptosis-inducing drug in the treatment of breast cancer.

Elicitation by chemical means including heavy metals is one of a new technique for drug discoveries. In this research, the effect of heavy metals on marine actinobacteria Streptomyces sp. H-1003 for the production of enterocin, with a strong broad spectrum activity, along optimized fermented medium was firstly investigated. The optimum metal stress conditions consisted of culturing marine actinobacteria strain H-1003 with addition of cobalt ions at 2mM in optimized Gause's medium having starch at 20mg/L for 10 days at 180 revolution/min. Under these conditions, enterocin production was enhanced with a value of 5.33mg/L, which was totally absent at the normal culture of strain H-1003 and much higher than other tested metal-stress conditions. This work triumphantly announced a prodigious effect of heavy metals on marine actinobacteria with fringe benefits as a key tool of enterocin production.

MicroRNAs (miRNAs), small and non-coding endogenous RNAs ∼22 nucleotides (nt) in length, have been known to regulate approximately 30 % of human gene expression at the post-transcriptional and translational levels. Accumulating data have demonstrated that certain miRNAs could exert an oncogenic and/or tumor suppressive function and might play essential roles in the regulation of apoptosis and autophagy in cancer. In this review, we summarize that certain oncogenic and tumor suppressive miRNAs could modulate apoptotic pathways in different types of cancer. Subsequently, we demonstrate that other miRNAs might play regulatory roles in the autophagic pathways of cancer. A limited number of oncogenic/tumor suppressive miRNAs could regulate apoptosis and autophagy, respectively, and cooperatively. Taken together, these findings would provide a new clue to elucidate more apoptotic and/or autophagic mechanisms of miRNAs for designing potential novel therapeutic strategies in cancer.

Beclin-1 (the mammalian ortholog of yeast ATG6) has been well-characterized to play a pivotal role in autophagy that is a major catabolic pathway in which the cell degrades macromolecules and damaged organelles. Beclin-1 structure has been identified to contain three identifiable domains, including a short Bcl-2-homology-3 (BH3) motif, a central coiled-coil domain (CCD) and a C-terminal half encompassing the evolutionarily conserved domain (ECD). Recent data indicate that Beclin-1 may interact with some co-factors such as Class III phosphatidylinositol 3-kinase (PI3KCIII)/Vps34, Vps15, ATG14L/Barkor, UVRAG, Bif-1, Rubicon, Ambra1, HMGB1, Survivin, Akt and Bcl-2/Bcl-XL to positively or negatively orchestrate the Beclin-1 interactome, thereby co-regulating the autophagy process. Here, we summarize that Beclin-1 serves not only as a key autophagic regulator with its specific interactors, but as a potential therapeutic target in cancer.