Cd133

To evaluate stem cell marker expression, neurospheres were dissociated mechanically or enzymatically with Accutase (Gemini Bioscience, Sacramento, CA). To facilitate adherence, cells were plated on poly-L-lysine/laminin coated four-well plates in neurosphere media. Cells were fixed in 4% paraformaldehyde, blocked and permeabilized with a 5% bovine serum albumin (BSA) with 0.6% Triton-× 100 and then treated with the primary antibodies Nestin (Abcam, Cambridge, MA), Sox2, Musashi 1, CD44, Bmi-1 (Cell Signaling Technology, Danvers, MA), CD133 (Biorbyt, Cambridge, UK) and A2B5 (A2B5 clone 105, ATCC, Manassas, VA). A “no primary control” was included for all antibodies tested for all cell lines. For these, the cells were incubated with only the antibody diluent (2.5% BSA, 0.3% triton, balance PBS). Cells were then treated with a fluorochrome-conjugated secondary antibody followed by Prolong Gold Antifade Reagent with DAPI (Thermo Fisher Scientific, Waltham, MA). Samples were examined under an EVOS FLoid Cell Imaging Station fluorescent microscope (Thermo Fisher Scientific, Waltham, MA).

The use of fresh liver tumor specimens was approved by the research ethic committees at the Catholic University (South Korea). Informed consent was obtained from all patients. Samples were fixed with 4% paraformaldehyde for fluorescent staining. Samples were permeabilized with 0.4 M glycine and 0.3% Triton X-100, and nonspecific binding was blocked with 2% normal swine serum (DAKO, Glostrup, Denmark). Staining was performed as described previously [57 (link)], using the primary anti-ALDH1 (Abcam, Cambridge, MA, USA, ab52492), CD133 (Biorbyt, Cambridge, UK, orb114000), Wnt1 (Abcam, Cambridge, MA, USA, ab15251), β-catenin (Cell Signaling Technology, Beverly, MA, USA, #9562), and PCNA (Vector Laboratories, Burlingame, CA, USA, VP-RM04) antibody. Samples were examined by fluorescence microscopy (Zeiss LSM 510 Meta). The calculation of expression was based on green fluorescence area and density divided by cell number, as determined from the number of DAPI-stained nuclei, in three randomly selected fields for each sample from a total of three independent experiments.

Western blot was performed as described previously [20 (link)] and the antibodies used were CD133 (Biorbyt, orb10288), OCT4 (Santa Cruz, sc-9081), c-MYC (Santa Cruzs, c-47694), NANOG (Santa Cruz, sc-293121), SOX2 (Millipore, AB5603), and β-actin (Abmart, P30002). Immunoreactive bands were then probed for 2 h at room temperature with the appropriate horseradish peroxidase (HRP)-conjugated secondary antibodies, anti-Rabbit IgG-HRP (GE Healthcare, NA934V), or goat anti-Mouse IgG (H + L)/HRP (ZSGB-BIO, ZB-2305). The protein bands were detected by Enhanced ECL AmershamTM prime western blotting detection reagent (GE Healthcare, RPN2232).