The Expression of Gastrin and Gastrin/ CCK-B Receptor mRNA in Cancer and Normal Tissue of Large Intestine

ABSTRACT

PURPOSE: Gastrin, a peptide hormone produced by the G cells of the gastric antrum, plays a major role in regulating acid secretion in the stomach, and acts as a trophic factor in the gastrointestinal tract. The relationship between gastrin and the development of colorectal cancer remains controversial. To study its possible role in development or proliferation of colorectal cancer, we evaluated the expression of gastrin and gastrin/CCK-B receptor mRNA in cancer and normal tissue from colorectal cancer patients. We also reviewed clinical records to evaluate the correlations between gastrin receptor expression and clinical characteristics of colorectal cancer. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate mRNA expression for gastrin and gastrin/CCK-B receptor in 26 surgical specimens of colorectal cancer. RESULTS: The mRNA expression of gastrin was detected in 24 out of 26 cancer specimens and 9 out of 26 normal colon specimens (p0.05). There was no significant correlation between gastrin receptor expression and clinical characteristics of colorectal cancer. CONCLUSIONS: The gastrin gene products might be more important than gastrin/CCK-B receptor in development or proliferation of colorectal cancer, which supports the hypothesis that gastrin gene products play a role in proliferation of colorectal cancer as an autocrine factor.