Figure 5. Stem-like cancer cell differentiation induced with Dickkopf-related protein 1 and Lefty-A (DL). A: Schematic diagram of the stem-like cancer cell (SLCCs) differentiation protocol. B: SLCCs plated on a poly-D-lysine/laminin-coated 6-well plate on day 0. C: Most of the SLCCs displayed neuron-like morphology with synapse-like structures after two to three days of induction. Scale bars=10 μm. D: An immunofluorescence assay showed that Dickkopf-related protein 1 (Dkk-1) and Lefty-A induced the neuron-like cell expression of glial fibrillary acidic protein (GFAP) and Rhodopsin (a photoreceptor marker) whereas SLCCs before differentiation with negative staining for GFAP and Rhodopsin. Scale bars=10 μm. E: Real-time PCR demonstrated that DL induction significantly upregulated the expression of Pax6, Lhx2, and Rx. The graphs show the mean±SD (n=3). White bars: control group. Black bars: DL-induced group. (*p<0.05, **p<0.01, ***p<0.001, with the Student t test).