Rapid Discovery of Substances with Anticancer Potential from Marine Fungi Based on a One Strain-Many Compounds Strategy and UPLC-QTOF-MS.

The secondary metabolites of marine fungi with rich chemical diversity and biological activity are an important and exciting target for natural product research. This study aimed to investigate the fungal community in Quanzhou Bay, Fujian, and identified 28 strains of marine fungi. A total of 28 strains of marine fungi were screened for small-scale fermentation by the OSMAC (One Strain-Many Compounds) strategy, and 77 EtOAc crude extracts were obtained and assayed for cancer cell inhibition rate. A total of six strains of marine fungi (P-WZ-2, P-WZ-3-2, P-WZ-4, P-WZ-5, P56, and P341) with significant changes in cancer cell inhibition induced by the OSMAC strategy were analysed by UPLC-QTOF-MS. The ACD/MS Structure ID Suite software was used to predict the possible structures with inhibitory effects on cancer cells. A total of 23 compounds were identified, of which 10 compounds have been reported to have potential anticancer activity or cytotoxicity. In this study, the OSMAC strategy was combined with an untargeted metabolomics approach based on UPLC-QTOF-MS to efficiently analyse the effect of changes in culture conditions on anticancer potentials and to rapidly find active substances that inhibit cancer cell growth.

A Terphenyllin Derivative CHNQD-00824 from the Marine Compound Library Induced DNA Damage as a Potential Anticancer Agent.

With the emergence of drug resistance and the consequential high morbidity and mortality rates, there is an urgent need to screen and identify new agents for the effective treatment of cancer. Terphenyls-a group of aromatic hydrocarbons consisting of a linear 1,4-diaryl-substituted benzene core-has exhibited a wide range of biological activities. In this study, we discovered a terphenyllin derivative-CHNQD-00824-derived from the marine compound library as a potential anticancer agent. The cytotoxic activities of the CHNQD-00824 compound were evaluated against 13 different cell lines with IC50 values from 0.16 to 7.64 µM. Further study showed that CHNQD-00824 inhibited the proliferation and migration of cancer cells, possibly by inducing DNA damage. Acridine orange staining demonstrated that CHNQD-00824 promoted apoptosis in zebrafish embryos. Notably, the anti-cancer effectiveness was verified in a doxycin hydrochloride (DOX)-induced liver-specific enlargement model in zebrafish. With Solafinib as a positive control, CHNQD-00824 markedly suppressed tumor growth at concentrations of 2.5 and 5 µM, further highlighting its potential as an effective anticancer agent.

Integrating Activity-Guided Strategy and Fingerprint Analysis to Target Potent Cytotoxic Brefeldin A from a Fungal Library of the Medicinal Mangrove Acanthus ilicifolius.

Mangrove-associated fungi are rich sources of novel and bioactive compounds. A total of 102 fungal strains were isolated from the medicinal mangrove Acanthus ilicifolius collected from the South China Sea. Eighty-four independent culturable isolates were identified using a combination of morphological characteristics and internal transcribed spacer (ITS) sequence analyses, of which thirty-seven strains were selected for phylogenetic analysis. The identified fungi belonged to 22 genera within seven taxonomic orders of one phyla, of which four genera Verticillium, Neocosmospora, Valsa, and Pyrenochaeta were first isolated from mangroves. The cytotoxic activity of organic extracts from 55 identified fungi was evaluated against human lung cancer cell lines (A-549), human cervical carcinoma cell lines (HeLa), human hepatoma cells (HepG2), and human acute lymphoblastic leukemia cell lines (Jurkat). The crude extracts of 31 fungi (56.4%) displayed strong cytotoxicity at the concentration of 50 µg/mL. Furthermore, the fungus Penicillium sp. (HS-N-27) still showed strong cytotoxic activity at the concentration of 25 µg/mL. Integrating cytotoxic activity-guided strategy and fingerprint analysis, a well-known natural Golgi-disruptor and Arf-GEFs inhibitor, brefeldin A, was isolated from the target active strain HS-N-27. It displayed potential activity against A549, HeLa and HepG2 cell lines with the IC50 values of 101.2, 171.9 and 239.1 nM, respectively. Therefore, combining activity-guided strategy with fingerprint analysis as a discovery tool will be implemented as a systematic strategy for quick discovery of active compounds.

The production of broad-spectrum antibiotics from phytopathogen Epicoccum sorghinum by culturing in host edible mushroom Thelephora ganbajun extract.

Metabolism of special endophytes and phytopathogens can be induced by the symbiotic interactions with the host. A phytopathogen Epicoccum sorghinum cultured in host mushroom Thelephora ganbajun medium exhibited different metabolites compared with that of ordinary medium. An unprecedented scaffold possessing the same substructure as perylenequinone mycotoxin, a first methyl rearrangement product of phytotoxin, epoxydon 6-methylsalicylate ester, three undescribed compounds, and an undescribed natural product were isolated from E. sorghinum cultured in T. ganbajun. Episorin A and epicosorin A were produced from E. sorghinum induced by culturing in host medium. Episorin A was the first example of perylenequinone analogue in the natural products. These induced compounds and other metabolites showed notable antibiosis against endogenous fungi, and insect existing in mushroom. Induced episorin A showed significant inhibitory effects on nitric oxide production in LPS-activated macrophages, and anti-acetylcholinesterase with the IC50 at 5.40 ± 0.25 µM, and 4.32 µM, respectively, and cytotoxicity against HL-60, A-549, SMMC-7721, MCF-7 and SW480 with IC50 at 14.21 ± 0.53, 17.93 ± 0.22, 18.17 ± 0.63, 28.36 ± 0.43, and 18.20 ± 1.03 µM.

Semisynthesis and biological evaluation of (+)-sclerotiorin derivatives as antitumor agents for the treatment of hepatocellular carcinoma.

Hepatocellular carcinoma is one of the most common primary hepatic malignancy. Herein, a series of semisynthesized derivatives (2-30) of the natural product (+)-sclerotiorin (1) was prepared and evaluated the cytotoxic activities against six cancer cell lines. Among them, 3 and 5 were the most effective compounds against human hepatocellular carcinoma Bel-7402 cell line with IC50 values of 1.45 and 1.15 µM, respectively. Molecular mechanism study showed that 5 disrupted the mitochondrial membrane potential and induced apoptosis in a caspase-dependent manner. In addition, 5 affected AKT and ERK signaling pathways and induced AKT and ERK proteins degradation through ubiquitin-proteasome system. Furthermore, 5 displayed significant in vivo anticancer effects in the xenograft models with decreasing the tumor mass by 52.5%. The safety evaluation was confirmed by acute toxicity subchronic toxicity tests, paraffin sections of mice organ and blood routine examination. Taken together, 5 can be developed as a potential therapeutic agent for hepatocellular carcinoma.

Brefeldin A Induces Apoptosis, Inhibits BCR-ABL Activation, and Triggers BCRABL Degradation in Chronic Myeloid Leukemia K562 Cells.

BACKGROUND: Chronic Myeloid Leukemia (CML) is a myeloproliferative disease caused by BCR-ABL oncoprotein. Tyrosine kinase inhibitors have been developed to inhibit the activity of BCR-ABL; however, drug resistance and side effect occur in clinic application. Therefore, it is urgent to find novel drugs for CML treatment. Under the guidance of cytotoxic activity, crude extracts of 55 fungal strains from the medicinal mangrove Acanthus ilicifolius were evaluated, and one potent cytotoxic natural compound, brefeldin A (BFA), was discovered from Penicillium sp. (HS-N-29). OBJECTIVE: This study was aimed to determine the cytotoxic activity of BFA and the effect on the activation and expression of BCR-ABL in K562 cells. METHODS: We evaluated cytotoxic activity by MTT assay and soft agar clone assay; apoptosis and cell cycle distribution by Muse cell analyzer. The protein level of BCR-ABL and signaling molecules was detected by western blotting, and the mRNA level of BCR-ABL was determined by RT-PCR. RESULTS: BFA inhibited cell proliferation, induced G2/M cell cycle arrest, and stimulated cell apoptosis in K562 cells. Importantly, for the first time, we revealed that BFA inhibited the activation of BCR-ABL and consequently inhibited the activation of its downstream signaling molecules in K562 cells. Moreover, we found BFA degraded BCR-ABL without affecting its transcription in K562 cells, and BFA-induced BCR-ABL degradation was related to caspase activation, while not to autophagy or ubiquitinated proteasome degradation pathway. CONCLUSION: Our present results indicate that BFA acts as a dual functional inhibitor and degrader of BCR-ABL, and BFA is a potential compound for chemotherapeutics to overcome CML.

Antifeedant and antiphytopathogenic metabolites from co-culture of endophyte Irpex lacteus, phytopathogen Nigrospora oryzae, and entomopathogen Beauveria bassiana.

Five new tremulane sesquiterpenoids were isolated from co-culture of endophyte Irpex lacteus, phytopathogen Nigrospora oryzae, and entomopathogen Beauveria bassiana. All compounds showed obvious antifeedant activities against silkworm with inhibition percentages of 73-99%, at concentrations of 50 µg/cm2. Compound 11 indicated notable antifeedant activity with inhibition percentage of 93% at concentration of 6.25 µg/cm2 among them. Compounds 2, 3, 4, 8, 9, 15 and 16 indicated anti-fungal activities against I. lacteus with MIC values ≤8 µg/mL, compounds 11, 12, 16-18 showed significant anti-fungal activity against N. oryzae with MICs ≤ 4 µg/mL, and compounds 2, 5, 12 and 18 indicated significant anti-fungal activity against B. bassiana with MICs ≤ 8 µg/mL. In addition, the I. lacteus should unite B. bassiana to inhibit the production of phytotoxins from N. oryzae in the ternary culture.

Paraverrucsins A-F, Antifeedant, and Antiphytopathogenic Polyketides from Rhizospheric Paraphaeosphaeria verruculosa and Induced Bioactivity Enhancement by Coculturing with Host Plant Dendrobium officinale.

Six new polyketides named paraverrucsins A-F (1-6) with oxabicyclic and dioxatricyclic skeletons, together with eight known metabolites (7-14), were discovered and isolated from the fermentation medium of Paraphaeosphaeria verruculosa. Paraverrucsin A-C possessed a novel decarboxylated skeleton compared with that of trichocladinols. Their structures were elucidated by extensive spectral analysis and DP4+ calculations. Paraverrucsins B/C and D/E were isolated as a mixture for the mutarotation occurred at C-2. Paraverrucsins B/C, D/E, F/trichocladinol B, 8, and 9 displayed antifeedant activities against silkworm larvae, with antifeedant index percentages ranging from 62.5 to 93.0%, at a concentration of 50 µg/cm2. Among them, Paraverrucsins B/C and 9 had EC50 values at 13.9 and 18.2 µg/cm2. Most compounds showed antifungal activities against phytopathogenic fungi with minimum inhibitory concentration (MIC) values of 16-64 µg/mL. Coculture of P. verruculosa and host plant Dendrobium officinale leads to the enhancement of antifeedant and antiphytopathogenic activities. Compounds 1, 2/3, 4/5, 6/14 were tested for cytotoxicity against five human carcinoma cell lines, HL-60, A549, MCF-7, SW480, and SMMC-7721, while they exhibited selected cytotoxicity against SW480 with inhibition ratios of 32-38% at a concentration of 40 µM.

Clinicopathological significance of human leukocyte antigen F-associated transcript 10 expression in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is a common malignancy of the gastrointestinal tract. The worldwide mortality rate of CRC is about one half of its morbidity. Ubiquitin is a key regulatory factor in the cell cycle and widely exists in eukaryotes. Human leukocyte antigen F-associated transcript 10 (FAT10), known as diubiquitin, is an 18 kDa protein with 29% and 36% homology with the N and C termini of ubiquitin. The function of FAT10 has not been fully elucidated, and some studies have shown that it plays an important role in various cell processes. AIM: To examine FAT10 expression and to analyze the relationship between FAT10 expression and the clinicopathological parameters of CRC. METHODS: FAT10 expression in 61 cases of CRC and para-cancer colorectal tissues was measured by immunohistochemistry and Western blotting. The relationship between FAT10 expression and clinicopathological parameters of CRC was statistically analyzed. RESULTS: Immunohistochemical analysis showed that the positive rate of FAT10 expression in CRC (63.93%) was significantly higher than that in tumor-adjacent tissues (9.84%, P < 0.05) and normal colorectal mucosal tissue (1.64%, P < 0.05). Western blotting also indicated that FAT10 expression was significantly higher in CRC than in tumor-adjacent tissue (P < 0.05). FAT10 expression was closely associated with clinical stage and lymphatic spread of CRC. FAT10 expression also positively correlated with p53 expression. CONCLUSION: FAT10 expression is highly upregulated in CRC. FAT10 expression is closely associated with clinical stage and lymphatic spread of CRC.

Two new farnesyl phenolic compounds with anti-inflammatory activities from Ganoderma duripora.

Ganoderma fungi have long been used as a famous traditional medicine and food in country of East Asia. In this work, two new farnesyl phenolic compounds, ganoduriporols A and B (1 and 2), were isolated from the fruiting bodies of Ganoderma duripora, and their structures were elucidated using various spectroscopic methods. Anti-inflammatory activities were assayed and evaluated for the two compounds. Ganoduriporols A and B exhibited dose-dependent anti-inflammatory effects in RAW 264.7 cells. Furthermore, ganoduriporol A was demonstrated to inhibit the production of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and prostaglandin E2 (PGE2) through the suppression of COX-2, MAPK and NF-κB signaling pathway in LPS-induced macrophage cells. These results suggested that these two new farnesyl phenolic compounds and the fruiting body of G. duripora could serve as anti-inflammatory agents for medicinal use or functional food.

Three new withanolides from the calyces of Nicandra physaloides.

Chemical investigation on ethyl acetate extract of the calyces of Nicandra physaloides resulted in the isolation of three new withanolides named as nicphysatone A (1), nicphysatone B (2), nicphysatone C (3), together with five known withanolides, nic 17 (4), nic 7 (5), nic 2 (6), withahisolide G (7) and nicaphysalin B (8). The structures were determined by comprehensive spectroscopic experiments. The discovery enriched the diversity of natural withanolides and could serve as scaffolds for the synthesis of more potent modified withanolides.

Hepatoprotective effects of triterpenoids from Ganoderma cochlear.

Two novel trinorlanostanes, cochlates A and B (1 and 2), with a 3,4-seco-9,10-seco-9,19-cyclo skeleton, as well as six new triterpenoids, fornicatins D-F (3-5) and ganodercochlearins A-C (6-8), together with five known triterpenoids (9-13), were obtained from the fruiting bodies of Ganoderma cochlear. The structural elucidation was achieved by interpretation of spectroscopic data, and compounds 2 and 7a were further characterized by X-ray crystallographic analysis. Fornicatins A, D, and F (10, 3, and 5) and fredelin (13) lowered the ALT and AST levels in HepG2 cells treated with H2O2, suggesting that they could display in vivo hepatoprotective activities.

Limonoids from the leaves of Toona ciliata var. yunnanensis.

Twelve limonoids, toonayunnanins A-L (1-12) and eleven known compounds (13-23) were isolated from the leaves of Toona ciliata var. yunnanensis, and their structures were elucidated by means of extensive spectroscopic analyses, particularly 1D and 2D NMR techniques. The inhibitory effects of all the isolated compounds were evaluated on human tumor cell lines, such as HL-60, SMMC-7721, A-549, MCF-7 and SW480. Cedrelone (13) and dysobinin (18) showed significant cytotoxicity, and toonayunnanin B (2) and epoxyazadiradione (14), were found to be slightly cytotoxic against the above cell lines. Furthermore, this study provides valuable information for the chemotaxonomy of T. ciliata varieties.

Isolation and bioactivity evaluation of terpenoids from the medicinal fungus Ganoderma sinense.

A new pentanorlanostane, ganosineniol A (1), eight new lanostane triterpenoids, ganosinoside A (2), ganoderic acid Jc (3), ganoderic acid Jd (4), ganodermatetraol (5), ganolucidic acid γa (6), ganolucidate F (7), ganoderiol J ( 8), and methyl lucidenate Ha ( 9), and a new sesquiterpenoid, ganosinensine (10), together with eleven known triterpenoids (11- 21), were isolated from the fruiting bodies of the fungus Ganoderma sinense. Chemical structures were determined based on spectroscopic evidence, including 1D, 2D NMR, and mass spectral data. Furthermore, all isolates were tested for cytotoxic activity and induction ability of hPXR-mediated CYP3A4 expression. Among them, ganoderic acid Jc (3) displayed selective inhibitory activity against HL-60 cells (IC50 = 8.30 µM), and ganoderiol E (11) exhibited selective cytotoxic activity against MCF-7 cells (IC50 = 6.35 µM). Meanwhile, compounds 5, 7, and ganolucidic acids B and C (19, 20) showed induction ability of hPXR-mediated CYP3A4 expression.

One new pregnane glycoside from the seeds of cultivated Brucea javanica.

A new pregnane glycoside, named (20R)-O-(3)-ß-D-glucopyranosyl-(1→2)-α-L-arabinopyranosyl-pregn-5-en-3ß,20-diol (1), and seven known compounds, brusatol (2), bruceine B (3), bruceine D (4), yadanziolide A (5), bruceine E (6), yadanzioside G (7), and yadanzioside B (8), were isolated from the cultivated dry seeds of Brucea javanica. The structure of 1 was elucidated on the basis of 1D- and 2D-NMR spectroscopic analyses. Their inhibitory effects on tumor cells were also tested. Compound 1 was slightly active against HL-60, SMMC-7721, A-549, and MCF-7 tumor cells. Compounds 2 and 3 demonstrated significant inhibitory activities against all tested cells. These results indicate that cultivated B. javanica could replace the wild plant as an antitumor plant resource.