FIG 4.

Estramustine and parthenolide elevate Candida glabrata fluconazole resistance. (A) The susceptibility of C. glabrata (strain ATCC 2001) to fluconazole was tested in the absence (DMSO vehicle alone) or presence of 5 μM estramustine or parthenolide in RPMI medium according to the CLSI broth microdilution protocol. Growth was quantified as OD₆₀₀ after 24 h of incubation at 35°C, and data are presented as percent growth relative to the drug-free control. (B and C) Checkerboard assays were performed in RPMI medium with C. glabrata (ATCC 2001) across a range of fluconazole doses and of estramustine (B) and parthenolide (C). After 24 h of incubation at 35°C, the growth in each well was quantified as OD₆₀₀, normalized to the untreated control well, and data are presented as heat maps. Data represent averages of results from technical duplicates from a single experiment representative of two biological replicates.