Screening and identification of 3-aryl-quinolin-2-one derivatives as antiviral agents against influenza A.

Quinolin-2-one represents an important and valuable chemical motif that possesses a wide variety of biological activities; however, the anti-influenza activities of quinolin-2-one-containing compounds were rarely reported. Herein, we describe the screening and identification of 3-aryl-quinolin-2-one derivatives as a novel class of antiviral agents. The 3-aryl-quinolinone derivatives were synthesized via an efficient copper-catalyzed reaction cascade that we previously developed. Using this synthetic method, preliminary structure-activity relationships of this scaffold against the influenza A virus infection were systematically explored. The most potent compound 34 displayed IC50 values of 2.14 and 4.88 µM against the replication of H3N2 (A/HK/8/68) and H1N1 (A/WSN/33) strains, respectively, without apparent cytotoxicity on MDCK cells. We further demonstrated that 27 and 34 potently inhibited the plaque formation of the IAV, rendering this scaffold attractive for pursuing novel anti-influenza agents.

Cytotoxic cytochalasins from marine-derived fungus Arthrinium arundinis.

Four new cytochalasins, arthriniumnins A-D (1-4), a new natural product, ketocytochalasin (5), as well as five known cytochalasin analogues (6-10) were isolated and identified from the fungus Arthrinium arundinis ZSDS1-F3 from the sponge Phakellia fusca. Their structures were elucidated by NMR spectroscopic and mass spectrometric analyses, as well as single crystal X-ray diffraction. Compounds 6 and 9 showed cytotoxicity against K562, A549, Huh-7, H1975, MCF-7, U937, BGC823, HL60, Hela, and MOLT-4 cell lines, with IC50 values ranging from 1.13 to 47.4 µM.

Hybrid compounds as new Bcr/Abl inhibitors.

A series of 2,4-disubstituted thiazole derivatives were designed and synthesized as new Bcr/Abl inhibitors by hybriding the structural moieties from FDA approved imatinib, nilotinib and dasatinib. The new inhibitors strongly suppressed the activity of Bcr/Abl kinase and potently inhibited the proliferation of K562 and KU812 leukemia cancer cells. Compound 4i displayed comparable potency with that of nilotinib in both biochemical kinase assay and cancer cell growth inhibition assay. These inhibitors might serve as lead compounds for further developing new anticancer drugs.

Amplification of unknown RNAs and RNA mixtures based on unique restriction enzyme cleavage in vitro.

Small RNAs, generally expressed at low levels, are difficult to reach usable levels from limited material. In this study, we have developed a novel method to amplify target RNA. The amplification procedure was carried out by sequential RT-PCR, effective separation, restriction enzymatic cleavage of cDNA strand, and run-off transcription in vitro of target RNA from its cDNA. Introduction of a unique stem-loop linker into cDNA strand is the key step to form a unique restriction enzyme recognition sequence that is not in cDNA sequence of target RNA. This method can be used to amplify RNA samples from various origins and has many advantages in amplifying unknown small RNAs and small RNA mixtures. The amplified RNA has the full sequence of original RNA except for an extra 5' G and an additional 3' A or C. The method worked well for amplifications of a microRNA, a piwi interacting RNA and two small RNA mixtures.

[SNP767A/T of FUS2 gene and lung cancer risk in Chinese population].

BACKGROUND: FUS2 gene locating at 3p21.3 is considered a promising candidate tumor suppressor gene. The aim of this study is to examine the difference in FUS2-767A/T polymorphism site between lung cancer patients and normal controls in Chinese population. METHODS: The genotype FUS2-767A/T was detected in 146 lung cancer patients and 113 normal controls by PCR-SSCP method. The relationship between lung cancer risk and difference in genotypes of FUS2 gene was analysed. RESULTS: FUS2-767A/T was significantly related to histological type (P=0.044), age of the patients with lung cancer (P=0.011) and vessel cancer embolus (P=0.031) in lung cancer group. There was no significant difference in distribution of FUS2 genotypes between lung cancer patients and normal controls (P=0.945). CONCLUSIONS: The results suggest that the FUS2-767A/T polymorphism may be a susceptibility factor for lung cancer among Chinese population.

Design, synthesis, and in vitro biological evaluation of novel 6-methyl-7-substituted-7-deaza purine nucleoside analogs as anti-influenza A agents.

Among many subtypes of influenza A viruses, influenza A(H1N1) and A(H3N2) subtypes are currently circulating among humans (WHO report 2014-15). Therapeutically, the emergence of viral resistance to currently available drugs (adamantanes and neuraminidase inhibitors) has heightened alarms for developing novel drugs that could address diverse targets in the viral replication cycle in order to improve treatment outcomes. To this regard, the design and synthesis of nucleoside analog inhibitors as potential anti-influenza A agents is a very active field of research nowadays. In this study, we designed and synthesized a series of hitherto unknown 6-methyl-7-substituted-7-deaza purine nucleoside analogs, and evaluated for their biological activities against influenza A virus strains, H1N1 and H3N2. From the viral inhibition assay, we identified some effective compounds, among which, compounds 5x (IC50 = 5.88 µM and 6.95 µM for H1N1 and H3N2, respectively) and 5z (IC50 = 3.95 µM and 3.61 µM for H1N1 and H3N2, respectively) demonstrated potent anti-influenza A activity. On the basis of selectivity index, we conceive that compound 5x may serve as a chemical probe of interest for further lead optimization studies with a general aim of developing novel and effective anti-influenza A virus agents.

Design, Synthesis, and Biological Evaluation of Pyrazolo[1,5-a]pyridine-3-carboxamides as Novel Antitubercular Agents.

A series of pyrazolo[1,5-a]pyridine-3-carboxamide derivatives were designed and synthesized as new anti-Mycobacterium tuberculosis (Mtb) agents. The compounds exhibit promising in vitro potency with nanomolar MIC values against the drug susceptive H37Rv strain and a panel of clinically isolated multidrug-resistant Mtb (MDR-TB) strains. One of the representative compounds (5k) significantly reduces the bacterial burden in an autoluminescent H37Ra infected mouse model, suggesting its promising potential to be a lead compound for future antitubercular drug discovery.

Sesquiterpenoids and xanthones derivatives produced by sponge-derived fungus Stachybotry sp. HH1 ZSDS1F1-2.

A new (2) and four known (1, 8-10) sesquiterpenoids, two new (3 and 4) and eight known (5-7, 11-15) xanthone derivatives were isolated from the cultures of sponge-derived fungus Stachybotry sp. HH1 ZDDS1F1-2. The structure of the compounds 1-15 was determined mainly by analysis of the one-dimensional and two-dimensional NMR spectroscopic data and by analogy with the data of those reported. Compound 1 was confirmed by X-ray crystallography. All the compounds were tested for their cytotoxic, antiinflammatory and antiviral (EV71) effects. Compounds 5, 7 and 11 showed significant cytotoxicity against selected human tumor cell lines. Compounds 3, 4 and 11 also displayed significant inhibitory activity against cycloooxygenase (COX-2). Compounds 4, 5 and 11 showed activities against intestinal virus EV71.

Engineering more stable, selectable marker-free autoluminescent mycobacteria by one step.

In our previous study, we demonstrated that the use of the autoluminescent Mycobacterium tuberculosis as a reporter strain had the potential to drastically reduce the time, effort, animals and costs consumed in evaluation of the activities of drugs and vaccines in live mice. However, the strains were relatively unstable and lost reporter with time without selection. The kanamycin selection marker used wasn't the best choice as it provides resistance to amino glycosides which are an important class of second line drugs used in tuberculosis treatment. In addition, the marker could limit utility of the strains for screening of new potential drugs or evaluating drug combinations for tuberculosis treatment. Limited selection marker genes for mycobacterial genetic manipulation is a major drawback for such a marker-containing strain in many research fields. Therefore, selectable marker-free, more stable autoluminescent mycobacteria are highly needed. After trying several strategies, we created such mycobacterial strains successfully by using an integrative vector and removing both the resistance maker and integrase genes by Xer site-specific recombination in one step. The corresponding plasmid vectors developed in this study could be very convenient in constructing other selectable marker-free, more stable reporter mycobacteria with diverse applications.

Pestalols A-E, new alkenyl phenol and benzaldehyde derivatives from endophytic fungus Pestalotiopsis sp. AcBC2 isolated from the Chinese mangrove plant Aegiceras corniculatum.

Five alkenyl phenol and benzaldehyde derivatives, pestalols A-E (1-5), as well as seven known compounds (6-12), were isolated from endophytic fungus Pestalotiopsis sp. AcBC2 derived from the Chinese mangrove plant Aegiceras corniculatum. Their structures were determined by spectroscopic analyses. Compounds 2 and 3 showed cytotoxicity against a panel of 10 tumor cell lines. Compounds 1-5, 8, 9, 11, and 12 showed inhibitory activities against Influenza A virus subtype (H3N2) and Swine Flu (H1N1) viruses. Compound 2 also showed inhibitory activity against tuberculosis.

A new naphthalene glycoside from the sponge-derived fungus Arthrinium sp. ZSDS1-F3.

One new naphthalene derivative, 1,8-dihydroxynaphthol-1-O-α-l-rhamnopyranoside (1), together with one known α-dibenzopyrone, alternariol (2), and five xanthones (3-7) were isolated from the sponge-derived fungus Arthrinium sp. ZSDS1-F3. All the isolated compounds (1-7) were established by comprehensive analysis of the spectral data, especially 1D and 2D NMR (HMQC and HMBC) spectra. In the primary bioassays, compound 3 exhibited moderate COX-2 inhibition, with IC50 values of 12.2 µM.

Design, synthesis and evaluation of a cellular stable and detectable biotinylated fumagillin probe and investigation of cell permeability of fumagillin and its analogs to endothelial and cancer cells.

Fumagillin (1), a natural product of fungal origin, and its analogs were discovered to be extremely potent and highly selective inhibitors restraining endothelial cell proliferation in vitro by covalently binding to MetAP2. In order to further understand the unclear biological mechanisms and pharmacological processes of fumagillin and its derivatives, fumagillin-biotin conjugate 8 was designed and synthesized, which is linked with a 27-atom connection chain and by urethane (carbamate) bonds between fumagillol and D-norbiotinamine. The conjugate 8 shows comparable activity and selectivity against HUVEC proliferation as fumagillin. It was demonstrated that the conjugate 8 is stable inside the cell and its linker is of a suitable length for the detection of biotin in native and denatured conditions. Using the conjugate 8, it was determined that the cell permeability of fumagillin (1) and its analogs are not responsible for their inhibitory activity difference against the proliferation of endothelial and cancer cells. Furthermore, we confidently believe that our present strategy is a versatile and convenient method for investigating drug's cell permeability along with other studies regardless of reversible or irreversible interaction between the drug and binding target/s.

Design and synthesis of pinanamine derivatives as anti-influenza A M2 ion channel inhibitors.

The adamantanes are a class of anti-influenza drugs that inhibit the M2 ion channel of the influenza A virus. However recently, the clinical effectiveness of these drugs has been called into question due to the emergence of adamantane-insensitive A/M2 mutants. Although we previously reported (1R,2R,3R,5S)-3-pinanamine 3 as a novel inhibitor of the wild type influenza A virus M2 protein (WT A/M2), limited inhibition was found for adamantane-resistant M2 mutants. In this study, we explored whether newly synthesized pinanamine derivatives were capable of inhibiting WT A/M2 and selected adamantane-resistant M2 mutants. Several imidazole and guanazole derivatives of pinanamine were found to inhibit WT A/M2 to a comparable degree as amantadine and one of these compounds 12 exhibits weak inhibition of A/M2-S31N mutant and it is marginally more effective in inhibiting S31NM2 than amantadine. This study provides a new insight into the structural nature of drugs required to inhibit WT A/M2 and its mutants.

Design, synthesis, and in vitro biological evaluation of 1H-1,2,3-triazole-4-carboxamide derivatives as new anti-influenza A agents targeting virus nucleoprotein.

The influenza virus nucleoprotein (NP) is an emerging target for anti-influenza drug development. Nucleozin (1) and its closely related derivatives had been identified as NP inhibitors displaying anti-influenza activity. Utilizing 1 as a lead molecule, we successfully designed and synthesized a series of 1H-1,2,3-triazole-4-carboxamide derivatives as new anti-influenza A agents. One of the most potent compounds, 3b, inhibited the replication of various H3N2 and H1N1 influenza A virus strains with IC(50) values ranging from 0.5 to 4.6 µM. Compound 3b also strongly inhibited the replication of H5N1 (RG14), amantidine-resistant A/WSN/33 (H1N1), and oseltamivir-resistant A/WSN/1933 (H1N1, 274Y) virus strains with IC(50) values in sub-µM ranges. Further computational studies and mechanism investigation suggested that 3b might directly target influenza virus A nucleoprotein to inhibit its nuclear accumulation.

Identification, structural properties and chelating capacity of miltipolone as a broad-spectrum inhibitor to cancer cells.

Miltipolone (1) was discovered as a good and broad-spectrum inhibitor against the growth of cancer cells from "Danshen" based on the activity-driven screening of TCMs. The structural features make 1 easily tautomerize between different forms and 1 is linked and stabilized by intermolecular O-H⋯O hydrogen bonds in the crystal structure. The interaction of 1 in ddH(2)O solution with Co(2+), Mn(2+), Zn(2+), Fe(2+) or Fe(3+) changed UV absorption values; the chelation of 1 with Fe(2+) or Fe(3+) also altered the characteristic UV absorption peaks. However, only did Fe(2+) reverse 1's inhibition against the growth of cancer cells; therefore, we concluded that 1 possibly acts as a Fe(2+) chelator to conduct its inhibitory activity.

A 5-microRNA signature for lung squamous cell carcinoma diagnosis and hsa-miR-31 for prognosis.

PURPOSE: Recent studies have suggested that microRNA biomarkers could be useful for stratifying lung cancer subtypes, but microRNA signatures varied between different populations. Squamous cell carcinoma (SCC) is one major subtype of lung cancer that urgently needs biomarkers to aid patient management. Here, we undertook the first comprehensive investigation on microRNA in Chinese SCC patients. EXPERIMENTAL DESIGN: MicroRNA expression was measured in cancerous and noncancerous tissue pairs strictly collected from Chinese SCC patients (stages I-III), who had not been treated with chemotherapy or radiotherapy prior to surgery. The molecular targets of proposed microRNA were further examined. RESULTS: We identified a 5-microRNA classifier (hsa-miR-210, hsa-miR-182, hsa-miR-486-5p, hsa-miR-30a, and hsa-miR-140-3p) that could distinguish SCC from normal lung tissues. The classifier had an accuracy of 94.1% in a training cohort (34 patients) and 96.2% in a test cohort (26 patients). We also showed that high expression of hsa-miR-31 was associated with poor survival in these 60 SCC patients by Kaplan-Meier analysis (P = 0.007), by univariate Cox analysis (P = 0.011), and by multivariate Cox analysis (P = 0.011). This association was independently validated in a separate cohort of 88 SCC patients (P = 0.008, 0.011, and 0.003 in Kaplan-Meier analysis, univariate Cox analysis, and multivariate Cox analysis, respectively). We then determined that the tumor suppressor DICER1 is a target of hsa-miR-31. Expression of hsa-miR-31 in a human lung cancer cell line repressed DICER1 activity but not PPP2R2A or LATS2. CONCLUSIONS: Our results identified a new diagnostic microRNA classifier for SCC among Chinese patients and a new prognostic biomarker, hsa-miR-31.

Pin1 expression contributes to lung cancer: Prognosis and carcinogenesis.

Lung cancer remains the most common cause of death for malignancy in both men and women. Current therapies for NSCLC patients are inefficient due to the lack of diagnostic and therapeutic markers. The phospho-Ser/Thr-Pro specific prolyl-isomerase Pin1 is overexpressed in many different cancers, including NSCLC, and may possibly be used as a target for cancer therapy. We identified 79 cases with the follow-up survival and investigated the clinical relevance of Pin1 expression in NSCLC patients. To validate the oncogenic potential of Pin1 in lung cells, we overexpressed Pin1 in Glc82 cells, and downregulated Pin1 by RNA interference in H1299 cells. The 5-year survival rate of the 79 patients was 54.6%. High expression of Pin1 correlated with poor survival by univariate analysis as well as by multivariate analysis, demonstrating that high expression of Pin1 was an independent prognostic factor. Consistent with the clinical findings, overexpression of Pin1 in Glc82 cells increased cell growth and colony formation and tumorigenicity in nude mice including cell migration, invasion. To further validate the role of Pin1 in lung cancer carcinogenesis, lentivirus-mediated siRNA targeting of Pin1 resulted in the stable suppression of both cell growth, anchorage-independent growth in soft agar and tumorigenic including cell migration, invasion in H1299 cells. Pin1 expression may be an unfavorable prognostic factor in patients of NSCLC patients, and these results indicate that Pin1 may have a role in tumor development and metastasis and thus could serve as a novel target for treatment of NSCLC.

Overexpression of RhoE has a prognostic value in non-small cell lung cancer.

BACKGROUND: Increasing evidence has suggested that RhoE plays an important role in carcinogenesis and progression. However, the correlation between RhoE expression and clinical outcome in lung cancer has not been investigated. METHODS: RhoE expression was detected by immunohistochemistry on tissue microarray containing samples from 115 patients with non-small cell lung cancer with a median follow-up of 54 months. RESULTS: RhoE was overexpressed in the cytoplasm of lung cancer cells compared with undetectable expression of RhoE in the adjacent nontumoral cells. Patients with RhoE-negative tumors had substantially longer cancer-related survival than did patients with RhoE-positive tumors. Multivariate analysis showed that RhoE overexpression was an independent marker for cancer-related survival in the entire population after adjusting for other prognostic factors. CONCLUSIONS: RhoE expression may serve as an unfavorable prognostic factor in patients with non-small cell lung cancer.