Interestingly, a study by Vychytilova-Faltejskova et al. identified piRNAs; piR5937, piR-28876, piR-23210, piR-32159 to be significantly downregulated in serum samples with piR5937 and piR-28876 found specifically only in CRC patients indicating further investigation of these markers as potential candidates for CRC diagnosis [82]. Here, PIR is linked to colorectal carcinoma.