Aim and Background: Vanadium compounds have both inhibitory and antitumor effects against chemical agents that cause cancer in a variety of cell lines. Also, previous studies demonstrated that curcumin in low concentrations, induce apoptosis and inhibit the cancer cells proliferation. The aim of this study is the synthesis of new complex of vanadium-curcumin and evaluation of anti-proliferative and apoptotic effects of this compound.

Material and methods: In this study, we synthesized the novel complex of vanadium, (1,7-bis [4-hydroxy-3-methoxyphenyl]-1,6-heptadiene-3,5- dionato) acetylacetonato oxovanadium (IV). The cytotoxicity of this complex was screened for antitumor activity against human breast cancer cells (MCF-7) human cervix epithelial carcinoma (HeLa), human colon cancer cell line (HT-29), human leukemia cell line (K-562), mouse neuroblastoma cell line (Neuro-2a) and normal mouse fibroblast cell line (L929) and using cisplatin as a comparative standard by MTT assay and Flow cytometry. The effect of synthesized compound on mouse fibroblast cell line (L929) was evaluated as control, simultaneously.

Results: The IC₅₀ ± SD (μM) values, calculated for synthesized complex against HeLa, MCF-7, HT-29, K-562, Neuro-2a and L929 cell lines are 5.65 ± 1.23, 2.48 ± 1.05, 42.6 ± 5.19, 3.99 ± 1.12, 65.3 ± 6.89 and  106.7 ± 8.98 respectively, while The IC₅₀ ± SD (μM) values, calculated for cisplatin as a comparative standard drug in chemotherapy against these cell lines, are 0.45 ± 0.12, 6.50 ± 2.11, 15.4 ± 4.93, 24.0 ± 2.93 and >200, respectively. Also the flow cytometry results for synthesized complex showed a high population of apoptotic cell (58.46%) and nearly 1.2-fold higher than cisplatin (48.03%) at the same concentration.

Conclusion: Our results showed that investigated complex exhibited higher cytotoxic activities against human breast cancer cells (MCF-7) and human leukemia cell line (K-562) compared to other cell lines. Our results confirmed that the synthesized compound have no cytotoxicity effects on mouse fibroblast cell line (L929). Also the flow cytometry results confirm that vanadium complex induce apoptosis in human leukemia cell line
(K-562).