Fig. 1. High DKK2 expression is present in human non-small cell lung cancers with APC mutation and predicts poor survival.

a Analysis of DKK2 expression in APC^wt, and APC^mutated non-small cell lung cancer groups. Data on DKK2 expression were obtained from the TCGA data sets from OncoLnc, then separate them into two groups according to the mutation status of APC. APC mutation includes 9 Deep Deletion, 17 Truncating Mutation, 34 Missense Mutation, and 1 Inframe Mutation. DKK2 read counts are RSEM RNA SeqV2 normalized. b Further divided APC^wt group into two groups according to mutation status of PI3CA mutation in lung squamous cell carcinoma. c Analysis of the correlation of DKK2 expression and survival. Data on DKK2 expression, overall survival were obtained from the TCGA data sets from OncoLnc. The high and low DKK2 expressers were grouped on the basis an arbitrary cutoff percentile of 25%. Mantel–Cox log-rank tests were done using the GraphPad Prism 7 software. (*p < 0.05; **p < 0.01)