Insulin-like growth factor 2 mRNA-binding protein 3 （IMP3） ex­pres­sion in colorectal cancer with liver metastasis

Abstract

Insulin-like growth factor 2 mRNA-binding protein 3 （IMP3） is an oncofetal RNA-binding protein involved in development of various cancers. The aim of this study was to examine the clinical background of patients with colorectal cancer （CRC） and to correlate IMP3 expression with liver metastasis in CRC clinicopathologically. The subjects were patients who underwent surgery for CRC, including those with simultaneous or later surgery for liver metastasis （n＝27） and those with no liver metastasis for 5 years after surgery （n＝32）, and a control group with recent surgery for CRC （n＝32）. IMP3 immunohistochemistry was defined as positive if strong staining was present in the cancer cell membrane and cytoplasm, and ＞10％ of the whole tumor was stained. IMP3 expression was correlated with tumor size （P＝0.002） and TNM stage （P＝0.02）. There was a correlation between IMP3 expression at primary CRC and liver metastasis sites （P＜0.001）. IMP3 expression did not differ significantly in primary CRC with （17/27, 62.9％） and without （14/32, 43.7％） liver metastases （P＝0.14）, but IMP3 expression at the colorectal site tended to be higher in cases with liver metastases. These results suggest that IMP3 expression may be an indicator for a risk of CRC liver metastasis.