Administration of isothiocyanate (E-4IB) and cisplatin leads to altered signalling and lysosomal export in human ovarian carcinoma sensitive- and cisplatin-resistant cells.

The aim of this study was to compare the effect of a new synthetic isothiocyanate derivative, ethyl 4-isothiocyanatobutanoate (E-4IB) and cisplatin (CDDP) in CDDP-sensitive human ovarian carcinoma cell line (A2780) and its resistant subline (A2780/CP). In parental cells, in comparison to untreated cells, sequential administration of both compounds led to higher exosomal dye (LysoTracker Green DND-26) retention and to alterations of mitogen-activated protein kinases (MAPKs), JNK, ERK and p38, or Akt kinase accompanied by changes in several anti- and pro-apoptotic molecules and lysosomal protein LAMP-1, as detected by Western blotting. On the contrary, variant A2780/CP cells were resistant to CDDP- or to combined sensitizer (E-4IB)/inducer (CDDP)-related apoptosis induction and exerted minor changes in the levels of these molecules.