The aim of our study was to determine whether the use of
cisplatin in the presence
echistatin in MDA-MB-231
breast cancer cells leads to a reduction of toxic effects associated with the use of
cisplatin. The expression of β1-integrin and
insulin-like growth factor 1 receptor (IGF-IR), signaling pathway
protein expression:
protein kinase B (AKT),
mitogen-activated protein kinases (ERK1/ERK2),
nuclear factor kappa B (NFκB), and
caspase-3 and -9 activity was measured after 24 h of incubation with tested compounds to explain detailed molecular mechanism of induction of apoptosis. The viability of MDA-MB-231
breast cancer cells was determined by
3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.
Annexin V-FITC/
propidium iodide staining assay was performed to detect the induction of apoptosis. Inhibition
DNA biosynthesis was determined by [3H]
thymidine incorporation into
DNA. The expression of of β1-integrin, IGF-IR, AKT, ERK1/ERK2, NFκB,
caspase-3 and -9 was evaluated using Western blot. The results suggest that treatment of MDA-MB-231
breast cancer cells for 24 h
cisplatin plus
echistatin severely inhibits cell growth and activates apoptosis by upregulation of
caspase-3 and -9 expressions. The effect was stronger than treatment
cisplatin and
echistatin alone. In this study, we have found that
cisplatin plus
echistatin treatment decreases
collagen biosynthesis in MDA-MB-231
breast cancer cells stronger than the individual compounds. The inhibition was found to be dependent on the β1-integrin and IGF receptor activation. A significant reduction of ERK1/ERK2, AKT expression in
cancer cells after
cisplatin plus
echistatin treatment was also found. The
cancer cells treated by
echistatin,
cisplatin, and in particular the combination of both compounds drastically increased expression of NFκB
transcription factor. Our results suggest that combined
therapy cisplatin plus
echistatin is a possible way to improve selectiveness of
cisplatin. This mechanism probably is due to downregulation of expression of β1-integrin and IGF-IR receptors, and the signaling pathway
proteins induced by these receptors. Our results suggest that
therapy cisplatin plus
echistatin is a possible way to improve selectiveness of
cisplatin.