ALKBH5 gene is a novel biomarker that predicts the prognosis of pancreatic cancer: A retrospective multicohort study

BACKGROUNDS/AIMS: Discovery of new prognostic factors for cases in which the pancreatic cancer scoring and staging system does not result in a clear definition is imperative. We examined the role of Human AlkB homolog H5 (ALKBH5) as a prognostic marker for pancreatic cancer. METHODS: Patient data were extracted from the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). The prognostic value of ALKBH5 was confirmed via analysis of ALKBH5 and other clinical factors, such as age, sex, and stage, using the time-dependent area under the curve (AUC) of Uno's C-index, the AUC value of the receiver operating characteristics (ROC) at three years, the Kaplan-Meier survival curve, and multivariate analysis. RESULTS: ALKBH5 showed excellent prognosis prediction in comparison with existing markers in the two independent cohorts (n=262). Kaplan-Meier survival analysis showed that ALKBH5 expression was positively associated with overall survival (log-rank test, ICGC, p=0.001; TCGA, p=0.01). Notably, comparison of C-index and AUC values in ROC analysis showed that ALKBH5 was associated with high C-index and AUC values compared with other clinical variables (C-index: ICGC, 0.621; TCGA, 0.614 and AUC at three years: ICGC, 0.609; TCGA, 0.558). Multivariate analysis demonstrated thatALKBH5 is an independent prognostic factor (ICGC, p=0.0123; TCGA, p<0.001). CONCLUSIONS: These findings contribute to the study of RNA methylation in pancreatic cancer. We believe that ALKBH5 is a new prognostic marker for pancreatic cancer.