BACE1 and Alzheimer disease: We demonstrate three applications of miRDRN: to explore the molecular and network properties of the single disease colorectal neoplasm; to study the comorbidity of the disease-pair Alzheimer’s disease-Type 2 diabetes (AD-T2D); and, by using miRDRN to construct a miRNA regulatory sub-network centered on the gene BACE1, to look for insights that may explain why several anti-AD, BACE1 inhibiting drugs that failed recent late-phase trials worsened conditions of treatment groups.