Low density lipoprotein receptor and mRNA expression in human colorectal cancer.

BACKGROUND We have previously show that, 63.3% of colorectal cancers did not express the Low Density Lipoprotein Receptor (LDLR). We now report the findings of a study on the expression of LDLR and its mRNA in neoplastic tissue specimens of human colorectal cancer (CRC), carried out to verify whether the absence of the LDLR in these tumours is reflected by the absence of its transcript. MATERIALS AND METHODS 32 patients (10 females and 22 males) operated for CRC were included in the study. The LDLR levels were evaluated by immunoenzymatic assay. The LDLR-mRNA, reverse-transcribed and then amplified by polymerase chain reaction, was detected by chromatography. RESULTS The LDLR protein was present in 12 out of the 32 patients. LDLR-mRNA expression was detected in 17 out of the 32 patients. The absence of the LDLR protein was reflected by the absence of its transcript in 13 out of the 20 tumours; The LDLR mRNA levels were significantly higher in the tumours that did not expres LDLR. CONCLUSION The variable expression of the LDLR protein and LDLR mRNA in CRC detected in this study suggests the possibility that different therapeutic strategies may be indicated for these tumours.