Following the publication of this article, the authors noted that there was an error in Fig. 4. The lines representing the two groups were indicated incorrectly in all graphs in Fig. 4. A corrected version of Fig. 4 is presented below. Furthermore, we regret any inconvenience this error may have caused. [the original article was published in the International Journal of Oncology 49: 1369-1376, 2016; DOI: 10.3892/ijo.2016.3638].