Fig. 1

High expression of RETSAT correlated to poor survival in PDAC patients. A The expression of RETSAT in PDAC tumor tissues (n = 174) from The Cancer Genome Atlas database compare to normal tissues from The Cancer Genome Atlas database and GTEx database (n = 252). B,C qPCR (B) and immunoblotting analysis (C) of RETSAT in human pancreatic duct epithelial (HPDE) cell line HPDE6-C7, pancreatic cancer cell lines PANC-1 and BxPC-3, the exposure time was 0.2 s (short exposure) and 1 s (long exposure) respectively in (C). D Kaplan-Meier curve for overall survival of PDAC patients (n = 174) with low vs high expression of RETSAT. The data was downloaded from TCGA dataset and re-analyzed. E Quantification of IHC integrated density of RETSAT in PDAC tissue microarray using image J software. Ninety adjacent tissues and corresponding tumor tissues were calculated. F Classification of PDAC microarray tissues into RETSAT high (n = 42) and low (n = 48) subgroups based on the ratio of RETSAT integrated density in tumor tissues versus own adjacent tissues. Tissues with ratio greater than 1.5 were defined as RETSAT-high, while lower than 1.5 were defined as RETSAT-low. G Overall survival time (months) of RETSAT-high and RETSAT-low subgroups based on microarray information. The figure shows the Kaplan–Meier survival curves. H, I Quantification of IHC integrated density of RETSAT in PDAC clinical tissues using image J software (H), 80 tumor tissues were calculated and divided into RETSAT high (n = 40) or low (n = 40) subgroups (I) based on IHC integrated density of RETSAT. J Kaplan–Meier curve for overall survival of RETSAT-high and RETSAT-low subgroups based on clinical information. K Representative images of immumohistochemistry staining of RETSAT in clinical PDAC tissues. L 38 PDAC tissues collected from clinical surgeries ahead of gemcitabine based treatment were classified into RETSAT high (n = 19) or low (n = 19) subgroups based on IHC integrated density of RETSAT. M Kaplan–Meier curve for overall survival of PDAC patients after surgery and followed by gemcitabine based therapy. Scale bar = 200 μm in (K), n = 3 independent experiments unless otherwise stated. All data are presented as mean ± SEM. P values were calculated using a two-tailed student’s t test