g 361 cells  (ATCC)

Journal: Apoptosis

Article Title: HSP90 inhibition potentiates oxidant-based antimelanoma action of novel thioquercetin derivatives by compromising AhR/CYP1A1 pathway

doi: 10.1007/s10495-026-02311-4

Figure Lengend Snippet: Quercetin derivative-induced apoptotic cell death in four melanoma cell lines, namely A375, MM370, G-361, and SH-4 using 2D cell culture system ( A ) and thioquercetin-mediated effects on A375 cell-based 3D melanoma spheroids ( B ). ( A ) Human normal fibroblasts (BJ cells) served as control cells. Cells were treated with quercetin (Q) and fourteen quercetin derivatives (5 µM for 24 h, BJ cells were also treated with 10 µM quercetin derivatives). Apoptosis and necrosis were evaluated using dual staining based on Annexin V staining and 7-AAD staining, and flow cytometry. Bars indicate SD, n = 3, *** p < 0.001, ** p < 0.01, * p < 0.05 compared to control (CTR) (ANOVA and Dunnett’s a posteriori test). A blue horizontal line is used to emphasize the action of quercetin derivatives compared to CTR. Representative dot-plots are also shown. Blue arrows indicate the most pronounced action of three thioquercetins, namely thioQ, thioQ(OAc) 4 , and thioQ(OAc) 5 against melanoma cells and no action against BJ normal cells. These three thioquercetins were selected for further analysis. ( B ) Multicellular spheroid-formation assay (left and bottom) and clonal spheroid-formation assay (right) were considered. (Left panel) Box plots showing the area of multicellular spheroids formed by seeding 8x10 3 A375 cells in dedicated plates in the presence of quercetin or its derivatives at the concentration of 5 µM. Each dot represents the area of an individual spheroid, measured using the BioTek Cytation 5 Cell Imaging Multimode Reader, and expressed as a percentage relative to untreated controls (CTR). Live/dead staining of multicellular A375-based spheroids was also considered (bottom panel). Images were captured using the BioTek Cytation 5 Cell Imaging Multimode Reader and representative microphotographs are shown. Scale bar, 1x10 3 μm; PI, propidium iodide (red); Hoechst, Hoechst 33342 (blue). (Right panel) Box plots showing the number of spheroids formed by seeding 250 cells in semi-solid Matrigel in the presence of quercetin or its derivatives at the concentration of 5 µM. Each dot represents the spheroid count per well, expressed as a percentage relative to untreated controls (CTR). Box and whisker plots are shown, n = 3, *** p < 0.001, * p < 0.05 compared to control (CTR) (ANOVA and Dunnett’s a posteriori test), ### p < 0.001, ## p < 0.01, # p < 0.05 compared to the treatment with quercetin (ANOVA and Tukey’s a posteriori test)

Article Snippet: Four melanoma cell lines were used, namely A375 (malignant melanoma/epithelial, CRL-1619TM, ATCC, Manassas, VA, USA), MM370 (malignant melanoma/epithelial, 10092316, CBA-1348, distributed by ECACC on behalf of CellBank Australia (CBA), Children’s Medical Research Institute, Westmead, Australia), G-361 (malignant melanoma/epithelial, 88030401, ECACC, Public Health England, Porton Down, Salisbury, UK), and SH-4 (melanoma/mixture of spindle-shaped and epithelial-like cells, CRL-7724TM, ATCC, Manassas, VA, USA).

Techniques: Cell Culture, Control, Staining, Flow Cytometry, Tube Formation Assay, Concentration Assay, Imaging, Whisker Assay

Journal: Apoptosis

Article Title: HSP90 inhibition potentiates oxidant-based antimelanoma action of novel thioquercetin derivatives by compromising AhR/CYP1A1 pathway

doi: 10.1007/s10495-026-02311-4

Figure Lengend Snippet: Synergistic action of HSP90 inhibition in thioquercetin derivative-treated melanoma cell lines, namely A375, MM370, G-361, and SH-4. ( A ) Melanoma cells were co-treated with 5 µM quercetin or thioquercetins and 100 nM 17-DMAG, a HSP90 inhibitor, for 24 h. Apoptosis was analyzed using two assays, namely Annexin V staining (top) and caspase 3/7 activity test (bottom), and flow cytometry. Bars indicate SD, n = 3, *** p < 0.001, ** p < 0.01, * p < 0.05 compared to control (CTR) (ANOVA and Dunnett’s a posteriori test), ### p < 0.001, ## p < 0.01, # p < 0.05 compared to the treatment with quercetin or corresponding thioquercetin derivative (ANOVA and Tukey’s a posteriori test). A blue horizontal line is used to emphasize the action of quercetin derivatives and HSP90 inhibitor compared to CTR. Representative dot-plots are also shown. Blue arrows indicate potentiated proapoptotic activity upon co-treatment. ( B ) A summarizing scheme showing the outcome of initial apoptosis-based cytotoxicity screening of fourteen quercetin derivatives against melanoma cells, namely the selection of the most effective quercetin derivatives - thioquercetins. The synergistic action of HSP90 inhibition is also denoted. CTR, control conditions; Q, quercetin treatment; 17D, treatment with the HSP90 inhibitor alvespimycin (17-DMAG)

Article Snippet: Four melanoma cell lines were used, namely A375 (malignant melanoma/epithelial, CRL-1619TM, ATCC, Manassas, VA, USA), MM370 (malignant melanoma/epithelial, 10092316, CBA-1348, distributed by ECACC on behalf of CellBank Australia (CBA), Children’s Medical Research Institute, Westmead, Australia), G-361 (malignant melanoma/epithelial, 88030401, ECACC, Public Health England, Porton Down, Salisbury, UK), and SH-4 (melanoma/mixture of spindle-shaped and epithelial-like cells, CRL-7724TM, ATCC, Manassas, VA, USA).

Techniques: Inhibition, Staining, Activity Assay, Flow Cytometry, Control, Selection