Fig. 1

Prediction of ZFAS1 overexpression in PAAD by bioinformatic analysis. a All differentially expressed lncRNAs, including ZFAS1,in the merged GEO dataset are shown in the heat map. Data were normalized by the RMA algorithm and log₂ transformed (blue: cancer samples; yellow: normal samples; red: upregulated lncRNAs; green: downregulated lncRNAs). b The ZFAS1 expression level in the Pei Pancreas dataset is shown, p < 0.05. c The ROC curve of the Pei Pancreas dataset showed an AUC for ZFAS1 of 0.889 (95% CI 0.771–0.959), p < 0.05. d ZFAS1 levels were positively associated with drinking habits (non-drinker vs occasional drinker, p < 0.05; occasional drinker vs weekly drinker, p < 0.05; weekly drinker vs daily drinker, p < 0.05). e Males had higher ZFAS1 levels than females, p < 0.05. f ZFAS1 levels were positively associated with tumour grade (grade 1 vs grade 3, p < 0.05). g Patients with different ZFAS1 levels and drinking habits showed survival differences, p < 0.05. h, i A TCGA-based analysis showed no difference in ZFAS1 expression or survival of patients stratified by ZFAS1 expression when comparing tumour tissue samples (n = 179) with normal tissue samples (n = 4). j The addition of normal samples from the GTEx database to the TCGA dataset (sample size increased from 4 to 171) improved the significance of the ZFAS1 expression difference, *p < 0.05. The vertical axes in h, j are log₂(TPM + 1)