Epithelial-mesenchymal transition (EMT) is an early and key process in the metastatic cascade during the progression of colorectal cancer (CRC). The aim of the present study was to identify deregulated EMT-related microRNAs (miRNAs/miRs) of CRC and assess the effect of differentially expressed miRNAs on the prognosis of patients with CRC. Genome-wide expression profiling of miRNAs was assessed in 3 EMT-negative and 3 EMT-positive CRC tissues. Differentially expressed miRNA was further validated in 90 pairs of CRC and corresponding paracarcinoma tissues using the reverse transcription-quantitative polymerase chain reaction (RT-qPCR). A total of 6 miRNAs (miR-10a-5p miR-204-3p, miR-1224-3p, miR-193a-3p, miR-365a-3p and miR-3678-3p) were identified to be differentially expressed between different EMT statuses of CRC tissues. Following validation using RT-qPCR, 3 miRNAs (miR-10a-5p, miR-365a-3p and miR-193a-3p) were selected for subsequent studies. The expression levels of miR-10a-5p, miR-193a-3p and miR-365a-3p were markedly increased compared with levels in corresponding paracarcinoma tissues. Survival analyses revealed that down-regulation of miR-193a-3p was associated with worse prognosis of patients with CRC, particularly in female and older patients. The results of the present study indicate that miR-193a-3p may be an EMT-related biomarker and serve as a novel prognostic factor for CRC.

The AURORA pathway participates in mitosis and cell division, and alterations in mitosis and cell division can lead to carcinogenesis. Therefore, genetic variants in the AURORA pathway genes may be associated with susceptibility to pancreatic cancer. To test this hypothesis, we used three large publically available pancreatic cancer genome-wide association study (GWAS) datasets (PanScan I, II/III and PanC4) to assess the associations of 7168 single nucleotide polymorphisms (SNPs) in a set of 62 genes of this pathway with pancreatic cancer risk in 8477 cases and 6946 controls of European ancestry. We identify 15 significant pancreatic cancer risk-associated SNPs in three genes (SMC2, ARHGEF7 and TP53) after correction for multiple comparisons by a false discovery rate < 0.20. Through further linkage disequilibrium analysis, SNP functional prediction and stepwise logistic regression analysis, we focused on three SNPs: rs3818626 in SMC2, rs79447092 in ARHGEF7 and rs9895829 in TP53. We found that these three SNPs were associated with pancreatic cancer risk [odds ratio (OR) = 1.12, 95% confidence interval (CI) = 1.07-1.17 and P = 2.20E-06 for the rs3818626 C allele; OR = 0.76, CI = 0.66-0.88 and P = 1.46E-04 for the rs79447092 A allele and OR = 0.82, CI = 0.74-0.91 and P = 1.51E-04 for the rs9895829 G allele]. Their joint effect as the number of protective genotypes also showed a significant association with pancreatic cancer risk (trend test P ≤ 0.001). Finally, we performed an expression quantitative trait loci analysis and found that rs3818626 and rs9895829 were significantly associated with SMC2 and TP53 messenger RNA expression levels in 373 lymphoblastoid cell lines, respectively. In conclusion, these three representative SNPs may be potentially susceptibility loci for pancreatic cancer and warrant additional validation.