Abstract: Objective    To investigate the expression and clinical significance of microRNA-224 and microRNA -378e in non-metastatic colonrectal cancer tissues and non-cancerous tissues surrounding colonrectal cancer in situ .Methods   The expression level of miR-224 and miR-378e in tumor and adjacent normal tissue from clinical colonrectal cancer patients without metastasis was detected by Chip - array . And the determination results were verified by real - time PCR . The correlation of miR-224 and miR-378e expession and clinicopathological features of colonrectal cancer was analyzed . Results   The expression level of miR-224 was significantly up-regulated in tumor tissue (P<0 .001)while miR-378e was down-regulated in tumor tissue , and validated by real-time PCR . The expression of miR-224 was strongly associated with Histological type(P<0 .05)，while miR-378e with Infiltration depth(P<0 .05) . Conclusion   miR-224 is a potent tumor promoter , while miR-378e is a potent tumor suppressor .

Key words: colorectal neoplasms, carcinoma, microRNAs, oligonucleotide array sequence analysis, polymerasechain reaction, miR-224, miR-378e