Hepatic cancer stem cell marker granulin-epithelin precursor and β-catenin expression associate with recurrence in hepatocellular carcinoma

// Phyllis F.Y. Cheung 1, 2, 3 , Tan To Cheung 3, 4 , Chi Wai Yip 1, 3 , Linda W.C. Ng 1 , Sze Wai Fung 1, 3, 5 , Chung Mau Lo 3, 4 , Sheung Tat Fan 3 , Siu Tim Cheung 1, 3, 6 1 Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China 2 Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, China 3 Department of Surgery, The University of Hong Kong, Hong Kong, China 4 Department of Surgery, Queen Mary Hospital, Hong Kong, China 5 School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China 6 Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China Correspondence to: Siu Tim Cheung, e-mail: stcheung@surgery.cuhk.edu.hk Keywords: β-catenin, cancer stem cells, granulin-epithelin precursor, hepatocellular carcinoma Received: July 17, 2015 Accepted: February 20, 2016 Published: March 01, 2016 ABSTRACT Granulin-epithelin precursor (GEP) has been demonstrated to confer enhanced cancer stem-like cell properties in hepatocellular carcinoma (HCC) cell line models in our previous studies. Here, we aimed to examine the GEP-expressing cells in relation to the stem cell related molecules and stem-like cell properties in the prospective HCC clinical cohort. GEP protein levels were significantly higher in HCCs than the paralleled non-tumor liver tissues, and associated with venous infiltration. GEP high cells isolated from clinical HCC samples exhibited higher levels of stem cell marker CD133, pluripotency-associated signaling molecules β-catenin, Oct4, SOX2, Nanog, and chemodrug transporter ABCB5. In addition, GEP high cells possessed preferential ability to form colonies and spheroids, and enhanced in vivo tumor-initiating ability while their xenografts were able to be serially subpassaged into secondary mouse recipients. Expression levels of GEP and pluripotency-associated genes were further examined in the retrospective HCC cohort and demonstrated significant correlation of GEP with β-catenin. Notably, HCC patients with high GEP and β-catenin levels demonstrated poor recurrence-free survival. In summary, GEP-positive HCC cells directly isolated from clinical specimens showed β-catenin elevation and cancer stem-like cell properties.