PIWIL1, PIWIL2, PIWIL3 and PIWIL4 were all deregulated with a dissociated profile: PIWIL1 and PIWIL3 had an abnormal emergent expression and the remaining PIWIL2 and PIWIL4 were variably downregulated in tumor tissues at RNA and protein levels (Figure 1). Here, PIWIL2 is linked to neoplasm.