Antitumor effects of carbon nanotube-drug complex against human breast cancer cells

To improve the bio-solubility and sustained-release properties of a carbon nanotube (CNT)-drug complex, the present study used a hydrophilic polymer, polyethylene glycol (PEG), and β-estradiol (E2), which targets the estrogen receptor in human breast cancer cells (HBCCs), to modify CNTs carrying lobaplatin (LBP) to form E2-PEG-CNT-LBP. The in vitro inhibitory effects against HBCCs and the in vivo pharmacological effect of the complex on heart, liver and kidney tissues were also evaluated. The results indicated that the inhibitory effects of this complex against HBCCs reached 80.44% within 72 h. A blood biochemical test of normal mice indicated that this complex reduced platelet counts, while aspartate aminotransferase levels were increased compared with those in the control group. Histopathological analysis revealed no obvious adverse effects on the heart, liver and kidneys. The in vivo results indicated that the novel E2-PEG-CNT-LBP complex had no obvious toxic effects while exhibiting sustained-release properties. The clearance of E2-PEG-CNT-LBP by non-specific uptake systems was delayed and its clearance was increased compared with LBP alone.