After the publication of the article the authors noted the following errors in the assembling of the figures. In Fig. 3A the tubulin panel for PC-3 cells is incorrect. The correct panel is reported below. In Figs. 3B and 5B the panels are incorrect. The correct panels are shown below. These changes do not affect the interpretation of the data or conclusions of this work [the original article was published in the International Journal of Oncology 30: 217-224, 2007; DOI: 10.3892/ijo.30.1.217].