Class II Hydrophobin HFBII: A Potential Carrier for Antitumor Agents

Background: Class II hydrophobin HFBII is a fungal protein with potential applications in pharmaceutical industry. Nevertheless, the antitumor activity of this protein has not been reported. Methods: In this study, natural type of Trichoderma reesei was cultivated in a submerged bioreactor to produce hydrophobin HFBII. The protein was purified using a reversed phase liquid chromatography, verified by MALDI-TOF, and then examined for its anticancer activity against T47D breast tumor cell line. Results: Different concentrations of hydrophobin HFBII from 1 nM to 500 μM were examined for this experiment. Hydrophobin HFBII with molecular weights of 7.0-7.2 kDa was achieved. The results of MTT assay showed that from the concentration of 100 μM and upwards, hydrophobin HFBII adversely affected the viability of the breast tumor cells. The IC50 value was reported to be 131 μM. Class II hydrophobin seems to be a very effective carrier for antitumor agent. Conclusion: This is the first report of HFBII cytotoxicity. However, there is lack of information regarding HFBII’s mechanism of action in cell death induction. Since, HFBII could play important roles in biomedicine, whether as a drug or a carrier for various kinds of pharmaceuticals, it is strongly suggested that its biological effects would be evaluated in detail.