Identification of high-risk Dukes B colorectal cancer by microRNA expression profiling: a preliminary study

Aim MicroRNAs (miRNAs) from tumour tissue and common gene mutations were studied to determine whether they predict the development of metastasis in patients with Dukes B colorectal cancer. Method Patients who underwent curative resection for Dukes B colorectal cancer who subsequently developed distant metastatic disease at some stage in the following 5 years (‘high-risk B’) were compared with case-matched controls of Dukes A, Dukes B (no metastases, ‘low-risk B’) and Dukes C patients without any detectable metastasis at 5 years of follow-up. MiRNAs from tumour and adjacent normal tissue and common gene mutations (KRAS, BRAF, PIK3CA) in primary cancer tissue were analysed to identify prognostic tissue markers for the development of metastasis in patients with Dukes B colorectal cancer. Results Expression of miR-15b and miR-135b was significantly downregulated (P