Fig. 1

Identification of circ-ERBIN as a candidate gene for metastasis of CRC. a Schematic illustration of three circRNAs in ERBIN gene. b RNA expression of the three circRNAs in different CRC cell lines was detected using qRT-PCR. c, d qRT–PCR for the abundance of ERBIN (left) and circ-ERBIN (right) RNA levels in HCT116 and RKO cells treated with RNase R (c) and followed by Sanger sequencing (d). The amount of ERBIN and circ-ERBIN RNA were normalized to the value measured in the mock treatment. e The relative RNA levels of ERBIN and circ-ERBIN were analyzed by qRT-PCR after treatment with Actinomycin D at the indicated time points in HCT116 cells. f, g qRT-PCR (f) and FISH (g) data indicating the circ-ERBIN is abundant in the cytoplasm. f GAPDH and U6 were applied as positive controls in the cytoplasm and nucleus for qRT-PCR experiments, respectively. g 18 s and U6 were applied as positive controls in the cytoplasm and nucleus for Fluorescence in situ hybridization (FISH) experiments, respectively. Nuclei were stained with DAPI. h qRT–PCR for the abundance of circ-ERBIN RNA in the samples of a mouse model of CRC metastasis. i RNA levels of circ-ERBIN in 59 pairs randomly selected CRC samples were detected by the junction primers (P < 0.001). j Expression of circ-ERBIN in different stages of CRC carcinoma samples. Values are the average of three independent experiments. Data are expressed as the mean ± SD, P<0.001