Polyphenon-E encapsulated into chitosan nanoparticles inhibited proliferation and growth of Ehrlich solid tumor in mice

Limited bioavailability of green tea polyphenols hampered their delivery to tumor and hence therapeutic effectiveness. This study investigated the antitumor activity of polyphenon-E (PE) encapsulated into chitosan nanoparticles (CSNPs) in Ehrlich solid tumor in mice. CSNPs-PE, with a particle size of 53–69 nm showed 83% entrapment efficiency and a sustained release of PE in pH = 7.4 at 37 °C. The data demonstrated a higher percentage of released drug in case of less crosslinked formulations. Ehrlich ascites carcinoma (EAC) cells (2.5 × 106/0.2 ml/mouse) were injected subcutaneously in the back of mice. Oral administration of CSNPs-PE for 30 days produced a significant decrease in tumor volume (53%) and weight (60%) compared with free PE and voids CSNPs (72%). Compared with free PE and control, cell cycle revealed G0/G1 arrest associated with decrease in proliferating cell nuclear antigen (PCNA). In tumor tissue of CSNPs-PE treated mice, compared with free PE, there were; 1) induction of Bax and p53, 2) activation of caspases-3,-8 and -9, and CD95, 3) decrease in Bcl-2 expression of 4) inhibition of VEGF and CD31 expressions in tumor tissue. In conclusion, encapsulation of PE into CSNPs provided a good platform for cancer chemotherapy and raised existing application of different polyphenols for nanochemotherapy/prevention