To obtain further insights into the biological differences of anaplastic lymphoma kinase positive anaplastic large cell lymphoma (ALK+ ALCL) and classical Hodgkin lymphoma (HL), we screened microbial culture filtrates to search for compounds that would exert a significantly greater effect on the viability of ALK+ ALCL cell lines compared to HL cell lines and identified Brefeldin A (BFA) as a suitable candidate. BFA inhibited phosphorylation of ALK and its downstream molecule, signal transducer and activator of transcription 3 (STAT3), one of the central pathways for the survival of ALK+ ALCL cells. In HL cell lines BFA did not affect CD30 expression or constitutive nuclear factor (NF)-κB activity, both of which are critical for HL cell survival.
View Article and Find Full Text PDFQuinofuracins A-E, novel anthraquinone derivatives containing β-D-galactofuranose that were isolated from the fungus Staphylotrichum boninense PF1444, induced p53-dependent cell death in human tumor cells. The structures of quinofuracins A-E, including absolute configurations, were elucidated by extensive spectroscopic analysis and chemical transformation studies. Quinofuracins were classified into three groups according to the aglycone moieties.
View Article and Find Full Text PDFWe have screened microbial culture filtrates for nitrogen monoxide (NO) production inhibitors using mouse macrophage cell line RAW264.7. As a result, paxilline, 21-isopentenylpaxilline and a novel analog of paxilline have been isolated from the culture filtrate of fungus Eupenicillium shearii.
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