Colorectal cancer metastasis detection primer and kit based on serum exosomal microRNAs

The invention discloses a colorectal cancer metastasis detection primer and a colorectal cancer metastasis detection kit based on serum exosomal microRNAs. According to the primer and the kit, the serum exosomal microRNAs differential expression profiles of colorectal cancer patients suffering from lymphatic metastasis and colorectal cancer patients not suffering from lymphatic metastasis are screened by adopting a second-generation high-throughput sequencing technology, then miR-483-5p with the most obvious up-regulation expression and miR-451a with the obvious down-regulation expression are subjected to large sample verification, and the result shows that miR-483-5p and miR-451a have the good identification and diagnostic efficiencies for colorectal cancer lymphatic metastasis. Meanwhile, combined miR-191-5p and U6 are taken as reference genes for carrying out relative quantification analysis on miR-483-5p and miR-451a in a sample, so that the data accuracy is improved. According to the primer and the kit,