Human gastric tissues simultaneously express the classical and alternative splicing cholecystokinin-B/gastrin receptors.

To explore whether cholecystokinin-B/gastrin receptor (CCKBRwt) gene and its alternative splicing variant preserving intron 4 (CCKBRi4sv) are expressed in human gastric carcinoma cell line and tissue, we detect mRNA expression of CCKBRwt and CCKBRi4sv in 30 gastric carcinoma and their corresponding normal tissues, 10 gastritis, and 2 autopsied normal stomach specimens as well as in a gastric carcinoma cell line SGC-7901 cells by RT-PCR and sequencing. The results revealed that human normal, inflammatory, and malignant gastric tissues simultaneously expressed the classical and alternative splicing cholecystokinin-B/gastrin receptor genes. The alternative splicing variant contains the intron 4 of cholecystokinin-B/gastrin receptor gene.