Figure 4.

HSF1 depletion abrogates SFN-induced paraspeckle formation. A, MCF7 cells were transfected with an HSF1-specific siRNA or a control siRNA. After 48 h, cells were left untreated or treated with SFN for 6 h, fixed, and subjected to coimmuno-FISH analyses by confocal microscopy using an antibody recognizing HSF1 (red) and fluorescent probes binding to NEAT1_2 (green). Nuclei were visualized with DAPI (blue). All experiments were performed in triplicate. Bars, 10 μm. B and C, intensities of NEAT1_2 containing paraspeckles and nuclear HSF1 staining in at least 250 cells were quantitated using Volocity software. (***, p ≤ 0.001.)