Synthesis of a platinum(II) complex with 2-(4-methoxy-phenyl) imidazo [4,5-f]-[1,10] phenanthrolin and study of its antitumor activity

• One platinum(II) complex with phenanthrolin derivative was synthesized.
• The platinum(II) complex exhibited selective cytotoxicity toward tumor cells.
• Its antitumor activity was achieved via inhibiting telomerase activity.
• Its mechanism is interaction c-myc quadruplex and activation of caspase-3/9.

A new platinum(II) complex of [PtII(L) (pn)]Cl·2H2O (1) (pn = 1,3-propanediamine) with 2-(4-methoxy-phenyl)imidazo [4,5-f]-[1,10]phenanthrolin (H-L) was synthesized and characterized. In complex 1, the platinum adopts a four-coordinated square planar geometry. Complex 1 exhibited selective cytotoxicity against NCI–H460, BEL-7402, SK-OV-3, SK-OV-3/DDP and HeLa cell lines with IC50 values in the micromolar range (9.7–35.8 μM), but low cytotoxicity toward normal human liver HL-7702 cells. Complex 1 caused HeLa cell cycle arrest at S phase and it induced HeLa apoptosis by the activation of caspase-3/9. Various experiments showed that complex 1 preferred to bind with G-quadruplex in c-myc. Taken together, we found that complex 1 exerted its antitumor activity mainly via inhibiting telomerase by interaction with c-myc quadruplex and activation of caspase-3/9.

One platinum(II) complex with phenanthrolin derivative was synthesized. It exhibited selective cytotoxicity toward tumor cells achieved via inhibiting telomerase activity by interaction c-myc quadruplex and activation of caspase-3/9.Figure optionsDownload as PowerPoint slide