ObjectiveTo systematically review the correlation between RUNX3 expression of colorectal cancer and its clinical characteristics. MethodsDatabases including PubMed, The Cochrane Library (Issue 9, 2013), EMbase, MEDLINE (Ovid), CNKI, VIP, WanFang Data and CBM were searched for collecting published international and domestic case-control studies on the correlation between RUNX3 expression of colorectal cancer and its clinical characteristics from the date of their establishment to October 1st, 2013. Two reviewers screened literature according to the inclusion and exclusion criteria, extracted data, and assessed the methodological quality of the included studies. Then, meta-analysis was performed using RevMan 5.2 software. ResultsA total of 7 case-control studies were included involving 804 cases in total (521 cases in colorectal cancer group and 383 cases in control group). The results of meta-analysis showed that, RUNX3 expression was lower in the colorectal cancer group than in the normal control group (OR=0.05, 95%CI 0.03 to 0.08, P < 0.000 01); higher in the moderately/highly-differentiated group than in the poorly differentiated group (OR=4.77, 95%CI 2.88 to 7.90, P < 0.000 01); higher in colorectal cancer with invasion depth on T1-T2 stage than in that on T3-T4 stage (OR=8.13, 95%CI 4.15 to 15.92, P < 0.000 01); and lower in the colorectal cancer accompanied with lymph node metastasis than that without lymph node metastasis (OR=0.23, 95%CI 0.14 to 0.36, P < 0.000 01), all with significant differences. No significant difference was found in RUNX3 expression between groups by age, sex and tumour location. ConclusionRUNX3 expression is notably correlated to colorectal cancer and its clinical characteristics. Due to the quantity and quality limitation of the included studies, the above conclusion still needs to be further proved by performing more high quality studies.