Design,Synthesis And Antitumor Activities Of Copper,Silver And Cobalt Complexes Containing Bisbenzimidazolyl Derivatives

Objective:In this paper,copper,silver and cobalt complexes containing bis-benzimidazolyl derivatives have been designed,synthesized and studied for their vitro anticancer activities,in order to provide experimental basis to develop high efficiency,low toxicity and no resistance of new anticancer drugs.Methods:Copper,silver and cobalt complexes containing bis-benzimidazolyl derivatives have been synthesized by hydrothermal method and the normal temperature of volatile,and the structure was characterized by IR spectroscopy and single crystal X-ray diffraction analysis.The antitumor effects of target complexes were screened against human liver cancer Hep-G2,human cervical cancer Hela,human breast cancer MCF-7 cell lines by means of MTT assay.The cell percentages of apoptosis and cell cycle distribution of complexes were measured with flow cytometry.The influences of complexes on the expression of Bax,Bcl-2 protein in cancer cells were evaluated by Western Blot method.The interaction way and binding constant of complexes with CT-DNA were determined by UV-visible spectra.Results:1.The molecular formula was analyzed by X-ray crystal diffraction,the molecular formula of complex 1 was C10H6CuN2,the molecular formula of complex 2 was C20H12Cu2N4,the molecular formula of complex 3 was C10H6CuN2,the molecular formula of complex 4 was C9.5H6CuN2.5,the molecular formula of complex 5 was C20 H14Cl2CuN4,he molecular formula of complex 6 was C2OH12Ag2N4,the molecular formula of complex 7 was C38H24CoN10.2.The MTT results showed that the effects of complex 1 and complex 4 on MCF-7 cell were significantly stronger than those of Hep-G2 and Hela cells,in 20?mol/L,the rate of inhibition to MCF-7 cell was 36.71%±1.79%and 40.72%±1.86%,respectively;Complex 2 and complex 3 were most sensitive to Hela,in 20?mol/L,the rate of inhibition to Hela cell was 58.94%±2.86%and 24.45%±4.51%,respectively;Complex 5,complex 6 and complex 7 had the greatest inhibitory effect on Hep-G2 cell,in 20?mol/L,the rate of inhibition to Hela cell was 58.61%±2.84%,76.71%±2.01%and20.20%±1.32%,respectively.3.The results of flow cytometry analysis showed that complex 1 andcomplex 4 inhibited the proliferation of MCF-7 mainly by inducing apoptosis,in 40?mol/L,the apoptosis rate of complex 1 was 31.59%±1.43%,in 30?mol/L,the apoptosis rate of complex 4 was 45.96%±2.06%;Complex 2 and complex 3 inhibited growth of Hela mainly by inducing apoptosis,in 40?mol/L,the apoptosis rate of complex 2 was 33.20%±0.65%,in 60?mol/L,the apoptosis rate of complex 3 was 33.66%±1.08%;Complex 5,complex 6 and complex 7 inhibited the proliferation of Hep-G2 by inducing apoptosis,in 40?mol/L,the apoptosis rate of complex 5 was 89.05%±0.98%,in 45?mol/L,the apoptosis rate of complex 6 was 87.14%± 1.46%,in 100?mol/L,the apoptosis rate of complex 7 was 44.66%±1.22%.Further studies complex 3 and complex 4 effected on the cell cycle distribution of Hela cell,MCF-7 cell respectively,complex 5,complex 6 and complex 7 effected on the cell cycle distribution of Hep-G2 cell,the results revealed that complex 3 could arrest the cell cycle of Hela cell at S phase,which may be one of mechanisms inducing cell apoptosis.Complex 4 could arrest the cell cycle of MCF-7 cell at G2 phase,which may be one of mechanisms inducing cell apoptosis.Complex 5 could arrest the cell cycle of Hep-G2 cell at S phase,which may be one of mechanisms inducing cell apoptosis.Complex 6 and complex 7 could arrest the cell cycle of Hep-G2 cell at G2 phase,which may be one of mechanisms inducing cell apoptosis.4.The influences of complex 4,complex 5 and complex 6 on the expression of Bax,Bcl-2 protein in MCF-7 cell and Hep-G2 respectively were studied by Western Blot method,the results showed that with increasing the concentration of complexes,the expression of Bax protein increased,the expression of Bcl-2 protein reduced.It may be concluded that the inducing apoptosis of MCF-7 and Hep-G2 cells may be related to the expression dysregulation of Bax,Bcl-2 protein in cells.5.The interaction of complexes with CT-DNA was determined by UV-visible spectra,the binding constants of complexes with CT-DNA indicated that the complexes could bind to DNA by partial intercalation,electrostatic interaction or groove binding,which would consequently lead to DNA damage and play anticancer effect,the binding constants of complexes 1?7 were 1.93×104M-1,4.67×103M-1,9.05×103M-1,5.05×104M-1,2.02×104M-1,4.94×104 M-1,3.73×103M-1,respectively.Conclusion:1.Among copper metal coordinates,complex 4 containing pyridine ring will ideally have a inhibition on the three cancer cells,especially for MCF-7 cell.It shows that complexes containing pyridine ring can enhance the antitumor activity.2.Complex 2 and complex 6 containing the same 1,3-bis-benzimidazole-phenyl compare with antitumor activities,the inhibitory effect of complex 2 on Hela and MCF-7 cells are better than those of complex 6.3.Complex 4 and complex 7 containing the same 2,3-bis-benzimidazole-pyridine compared with antitumor activities,the inhibitory effect of complex 4 is a best overall than those of complex 7.4.Seven complexes inhibit the proliferation of cancer cells mainly by inducing apoptosis;The mechanism of inducing cell apoptosis by complex 4,complex 5 and complex 6 may be related to the expression dysregulation of Bax,Bcl-2 protein in cells.Seven complexes can bind to DNA by partial intercalation,electrostatic interaction or groove binding,which will consequently lead to DNA damage and play anticancer effect.Through the research of this paper,it shows that this series of complexes have a well prospect in development and application and may be further studied for pre-clinical development.