title: Sample 40
organism: Homo sapiens
description: Protocols: Metachronous colorectal liver metastasis tissue samples and their adjacent non-malignant liver tissues surgically resected from patients.  Total RNA was extracted from tumor tissue using the TRIZOL reagent (Thermofisher) following the manufacturer's protocol. The tissue was first pulverized with mortar and pestle under liquid nitrogen.  1000 ng of total RNA was used for construction of small RNA libraries. The libraries were prepared using NEXTflex small RNA-Seq Kit v4 (PerkinElmer, Inc, Austin, USA), following the manufacturer's protocol. Quality of prepared libraries was checked by Tapestation 2200 using High Sensitivity D1000 kit (Agilent Technologies Inc., CA, USA) and quantity measured by the Qubit instrument using the Qubit dsDNA HS Assay Kit (ThermoFisher Scientific, MA, USA). Prepared libraries were pooled equimolarly.