Aim: This study aimed to examine the effects of the NF-κβ inhibitor parthenolide, the anti-carcinogenic drug cisplatin and their combinations on the NF-κβ and MEK1/MEK2 expression levels and phosphorylation status in the human monocytic leukemia cell line (THP-1).

Materials and methods: The human monocytic leukemia cells (THP-1 cell line) were treated for 48h with various doses of parthenolide (5, 10, 20 μM), cisplatin (1, 3, 10 μM ) and their combinations (1 μM Cis + 10 μM PTL and 3 μM Cis + 10 μM PTL). CD45, NF-κβ, MEK1/MEK2 expressions were analyzed by flow cytometry. The levels of NF-κβ, pNF-κβ, MEK1/MEK2, pMEK1/MEK2 proteins were detected by western blotting.

Results: The antiproliferative effect of parthenolide (10 μM) and cisplatin (1, 3 μM) was significantly increased with combination therapy (1 μM Cis + 10 μM PTL and 3 μM Cis + 10 μM PTL). NF-kβ expression level was significantly decreased at 5 μM PTL, 10 μM PTL groups and combination groups. Additionally, pNF-κβ phosphorylation decreased at the combination groups. MEK1/MEK2 expression was significantly increased at 5 μM PTL and 10 μM PTL groups.

Conclusion: The results show changes in expression of NF-kβ and MEK1/MEK2 proteins in leukemia cells treated with parthenolide and cisplatin combination. NF-kβ inhibitor parthenolide might be clinically useful, alone or in combination with chemotherapeutic agents, in particular with cisplatin for the treatment of hematological malignancies.