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This study conducted the solid fermentation process of Dioscorea nipponica using endophytic fungi C39 to determine the changes in the diosgenin concentration. The results revealed that endophytic fungi C39 could effectively biotransform the saponin components in D. nipponica. Moreover, the maximum increase in the diosgenin concentration reached 62.67% in 15 days of solid fermentation. MTT assay results demonstrated that the inhibitory effects of the fermentation drugs on four types of cancer cells (liver cancer cells (HepG2), stomach cancer cells (BGC823), cervical cancer cells (HeLa), and lung cancer cells (A549)) were better than those of the crude drugs obtained from D. nipponica. The chemical composition of the samples obtained before and after the biotransformation of D. nipponica was analyzed by UPLC-Q-TOF-MS. A total of 32 compounds were identified, 21 of which have been reported in Dioscorea saponins and the ChemSpider database and 11 compounds were identified for the first time in D. nipponica. The biotransformation process was inferred based on the variation trend of saponins, which included transformation pathways pertaining to glycolytic metabolism, ring closure reaction, dehydrogenation, and carbonylation. The cumulative findings provide the basis for the rapid qualitative analysis of the saponin components of D. nipponica before and after biotransformation. The 11 metabolites obtained from biotransformation are potential active ingredients obtained from D. nipponica, which can be used to further identify pharmacodynamically active substances. [ABSTRACT FROM AUTHOR]

Purpose: Disulfiram (DSF) is an approved drug for the treatment of alcohol dependence. Accumulating evidence indicates that DSF, alone or in combination with copper (Cu), possesses strong antitumor activity in various malignancies. This study investigated the effects of DSF on gastric cancer (GC) and the potential mechanisms involved.Methods: GC cell proliferation and apoptosis upon treatment with DSF with or without copper were analyzed using CCK-8 assay, colony formation assay, and flow cytometry. Glucose metabolism was investigated using glucose consumption and lactate production assays. The expression of caspase-3, Bcl-2, LC-3, P62, S6K1, c-Myc, GLUT1, PKM2, and LDHA was analyzed using western blot assay. In vivo nude mice studies were performed to verify the findings from in vitro analyses.Results: Our study showed that DSF was highly toxic to GC cells in a Cu-dependent manner. Nontoxic concentrations of Cu enhanced the inhibitory effects of DSF on cell viability and colony formation. DSF also induced apoptotic and autophagic cell death in the presence of Cu. In addition, DSF/Cu inhibited glycolysis and xenograft growth of GC cells by suppressing the expression of S6K1, c-Myc, and their downstream molecules, including GLUT1, PKM2, and LDHA.Conclusion: Our study demonstrated that DSF/Cu exerted antitumor activity against GC cells both in vitro and in vivo. DSF/Cu may represent a promising therapeutic strategy for the treatment of GC. [ABSTRACT FROM AUTHOR]

• The electrical conductivity and electron transport of two normal and one cancer breast cell lines were investigated and compared at nanometer spatial level and picoampere current level by Conductive Atomic Force Microscopy (CAFM). The electrical conductivity of the cancer breast cells is better than the normal breast cells. This work will be helpful in the further investigations of electrical conductivity of normal and cancer cells at nanometer level, and will also be useful in the early diagnosis of breast cancer and other kinds of cancers and tumors. Breast cancer is one of the most commonly diagnosed malignant cancers that threatens the health of women severely. The pathogenesis has not been revealed exhaustively due to the complex mechanisms. Evidences suggest that electrical conductivity properties play critical roles in cellular functions and activities. But the roles of electrical conductivity in pathogenesis of breast cancer cells have not been studied clearly at the nanometer level yet. In the present work, the electrical conductivity and electron transport of two normal and one cancer breast cell lines were investigated and compared at nanometer spatial level and picoampere current level by Conductive Atomic Force Microscopy (CAFM). The cell bodies of normal and cancer breast cells show the typical capacitor behaviors with little conductivity capability for electricity. The capacitance of cell bodies of the cancer breast cells is less than the normal breast cells. The conductivity of the processes of normal and cancer breast cells has also been investigated. The processes of the normal breast cells also exhibit the capacitor behavior. While the processes of the breast cells are electrically conductive along micrometer length scales, and show the semiconductor like conductive characteristics with Schottky barrier of 0.8391 V. All these demonstrate that the electrical conductivity of the cancer breast cells is better than the normal breast cells. This work will be helpful in the further investigations of electrical conductivity of normal and cancer cells at nanometer level, and will also pave new way in the distinguishing the cancer cells and tissues from the normal cells and tissues. The electrical conductivity of cells investigated by CAFM. (Left) the schematic of the cells studied by CAFM; (Middle) the topography of the process of the cell; (Right) the corresponding current image of the process of the cell. [Display omitted] [ABSTRACT FROM AUTHOR]