PROM1 and pachyonychia congenita: More specifically, we have shown that the co-targeting of EGFR and sonic hedgehog pathways by using gefitinib and cyclopamine with the chemotherapeutic drug, docetaxel or mitoxantrone resulted in supra-additive anti-proliferative, anti-invasive and apoptotic effects on diverse invasive and metastatic PC cell lines, including CD133+ SP WPE1-NB26 cells, as compared to individual agents and two-drug combinations [36], [52], [79].