Notably, unlike a prior Caucasian r

Notably, unlike a prior Caucasian report (28), these global miRNA aberrations within the tumor were not represented within the fecal miRNA profiles of CRC patients in our study. Osborn and Ahlquist (5) previously defined fecal markers from three sources: exfoliated, secreted and leaked markers. Exfoliated markers are derived from the shedding of colonocytes at the gut luminal surface; secreted markers are emanated from the epithelial cells lining the colonic lumen; and leaked markers are products of disturbed blood or lymph vessels following tumor growth. Our microarray data herein demonstrated that the unique fecal miRNA profile characterizing CRC in Asian patients was possibly associated with processes beyond the direct exfoliation of tumor cells in feces. These complex mechanisms remained unclear, although possible speculations were shedding of normal colonocytes that harbored altered miRNA profiles and the presence of leaked markers from blood in stool of CRC patients. In particular, the former postulation was supported by a recent report that alluded to changes in the miRNA milieu of normal mucosae given its interaction with the adjacent tumor (37). Notably, our observation posed considerable possibilities for future research into the origin of fecal miRNA markers and the multiple features of CRC.