Heat Shock Protein HSP27 Secretion by Ovarian Cancer Cells Is Linked to Intracellular Expression Levels, Occurs Independently of the Endoplasmic Reticulum Pathway and HSP27’s Phosphorylation Status, and Is Mediated by Exosome Liberation

Figure 2

Intracellular expression and secretion of HSP27 in OVCAR-3 cells transfected with the overexpression plasmid pHSP27 wt. (a) OVCAR-3 cells were transfected with 3.0 µg pHSP27 wt plasmid and empty control vector pcDNA3.1, respectively. Relative intracellular HSP27 expression was determined by Western blotting at indicated time points. HSP27 signal was normalized to β-actin. (b) Representative Western blots of experiments as described in (a). (c) Secreted HSP27 concentration in supernatants of OVCAR-3 cells determined by ELISA at indicated time points. Cells were treated as described in (a). Graphs of samples were calculated as the mean ± SD. values were determined by Student’s -test with () and () given as significant.

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