The aim of this study was to evaluate whether the cold-water extracts of Pleurotus eryngii var. ferulae (CWE-Pef) and Pleurotus nebrodensis (CWE-Pn), 2 of the most prized wild and cultivated edible mushrooms, can affect the tumor phenotype of human colon cancer HCT116 cells. Our results showed that treatment with CWE-Pef and CWE-Pn resulted in a significant inhibition of the viability of HCT116 cells and promoted apoptosis, as also demonstrated by the increase of Bax-to-Bcl-2 messenger RNA ratio. Moreover, we observed that both extracts were able to inhibit cell migration and to affect homotypic and heterotypic cell-cell adhesion. It also was found that treatment with CWE-Pef and CWE-Pn negatively modulated the phosphorylation of the protein tyrosine as well as the phosphorylation levels of extracellular signal-regulated kinase 1/2. In conclusion, the in vitro antitumor effects of CWE-Pef and CWE-Pn indicate that they can be considered as possible sources for new alternative therapeutic agents for cancer treatment.