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Background and Purpose: Pancreatic cancer is an exceptionally fatal disease. However, therapeutic drugs for pancreatic cancer have presented a serious shortage over the past few decades. Signal transducer and activator of transcription-3 (STAT3) is persistently activated in many human cancers where it promotes tumour development and progression. Natural products serve as an inexhaustible source of anticancer drugs. Here, we identified the natural product trienomycin A (TA), an ansamycin antibiotic, as a potential inhibitor of the STAT3 pathway with potent activity against pancreatic cancer.Experimental Approach: Effects of trienomycin A on transcriptional activity of STAT3 were assessed by the STAT3-luciferase (STAT3-luc) reporter system. In vitro and in vivo inhibitory activity of TA against pancreatic cancer made use of molecular docking, surface plasmon resonance (SPR) assay, MTS assay, colony formation assay, transwell migration/invasion assay, flow cytometric analysis, immunofluorescence staining, quantitative real-time polymerase chain reaction (PCR), western blotting, tumour xenograft model, haematoxylin and eosin (H&E) staining and immunohistochemistry.Key Results: Trienomycin A directly bound to STAT3 and inhibited STAT3 (Tyr705) phosphorylation, thus inhibiting the STAT3 pathway. Trienomycin A also inhibited colony formation, proliferation, migration and invasion of pancreatic cancer cell lines. Trienomycin A also markedly blocked pancreatic tumour growth in vivo. More importantly, trienomycin A did not show obvious toxicity at the effective dose in mice.Conclusions and Implications: Trienomycin A exerted anti-neoplastic activity by suppressing STAT3 activation in pancreatic cancer. This natural product could be a novel therapeutic candidate for pancreatic cancer. [ABSTRACT FROM AUTHOR]

The Microwave Temperature Sounder-II (MWTS-II) and Microwave Humidity and Temperature Sounder (MWHTS) onboard the Fengyun-3C (FY-3C) satellite can be used to detect atmospheric temperature profiles. The MWTS-II has 13 temperature sounding channels around the 60 GHz oxygen absorption band and the MWHTS has 8 temperature sounding channels around the 118.75 GHz oxygen absorption line. The data quality of the observed brightness temperatures can be evaluated using atmospheric temperature retrievals from the MWTS-II and MWHTS observations. Here, the bias characteristics and corrections of the observed brightness temperatures are described. The information contents of observations are calculated, and the retrieved atmospheric temperature profiles are compared using a neural network (NN) retrieval algorithm and a one-dimensional variational inversion (1D-var) retrieval algorithm. The retrieval results from the NN algorithm show that the accuracy of the MWTS-II retrieval is higher than that of the MWHTS retrieval, which is consistent with the results of the radiometric information analysis. The retrieval results from the 1D-var algorithm show that the accuracy of MWTS-II retrieval is similar to that of the MWHTS retrieval at the levels from 850-1,000 hPa, is lower than that of the MWHTS retrieval at the levels from 650-850 hPa and 125-300 hPa, and is higher than that of MWHTS at the other levels. A comparison of the retrieved atmospheric temperature using these satellite observations provides a reference value for assessing the accuracy of atmospheric temperature detection at the 60 GHz oxygen band and 118.75 GHz oxygen line. In addition, based on the comparison of the retrieval results, an optimized combination method is proposed using a branch and bound algorithm for the NN retrieval algorithm, which combines the observations from both the MWTS-II and MWHTS instruments to retrieve the atmospheric temperature profiles. The results show that the optimal combination can further improve the accuracy of MWTS-II retrieval and enhance the detection accuracy of atmospheric temperatures near the surface. [ABSTRACT FROM AUTHOR]