Pattern of glutaminase expression in primary colorectal cancer

Abstract

Objective: Expression of glutaminase isoforms (LGA and KGA) in human primary colorectal cancer compared to normal colon mucosa. Methods: The studies were performed on a group of 20 patients with primary colorectal cancer. Tumor tissue and surrounding colon mucosa taken 6-7 cm out of the tumor border (control) were used for studies. Expression of kidney-type (KGA) and liver-type (LGA) glutaminase isoforms was determined by RT-PCR (reverse transcriptase PCR). Results: KGA-mRNA expression was observed in all cases with CRC, in both tumor and normal mucosa. No significant differences were observed in its expression between tumor and normal colon mucosa. LGA-mRNA was present only in 10 out of 20 tumors, and it was absent from normal mucosa. Conclusion: KGA is the main glutaminase isoform expressed in normal and cancerous human mucosa. More studies are needed to explain why LGA is expressed only in some CRC tumors.