Chemotherapy, multidrug resistance (MDR), its modulation and relationship of these events to programmed cell death in human tumor cells

1. During the transition of HL60 cells from G1/S block, the activation of MAP kiinases was accompanied by the cell cycle inhibition and apoptosis induction which could result in the tumor cell activity alterations. 2. Sequential administration of E-4IB and CP in parental ovarian cancer cells (A2780), in comparison to resistant cells (A2780/CP), led to the changes in MAPK signaling and to the increased exosomal labeling retention that attests to the participation of exosomes in the CP-resistance in ovarian cancer cells. 3. Administration of SF on breast carcinoma MDA-MB-231 cells led to the modulation of cell molecules associated with epithelial-mesenchyme transition (EMT), cell matrix degradation, and to decreased cytokines levels and angiogenetic factors.