Thus, the data obtained by our group mechanistically shows that the presence of stemness gene amplifications in tumor cells led to ectopic expression of an entire cluster of stemness genes and boosted the proliferative activity of EpCam+ tumor cells, increased the concentration of EpCam+CD44+CD24– cancer stem cells, determined the EpCam+CD44lowCD24– to EpCam+CD44hiCD24low plasticity and was able to induce mammosphere formation. The gene discussed is EPCAM; the disease is neoplasm.