Expression And Significance Of GRP And GRPR In Colorectal Cancer And Colorectal Adenoma

Objective: To characterise the expression of gastrin-releasing peptide(GRP) and gastrin releasing peptide receptor(GRPR) in colorectal cancer(CRC), adenomatous polyps and normal colorectal mucosa, then analyze and explore the relationship between GRP/GRPR expression and clincopathliogical features. Dertermine the GRP concentration in serum of patients with CRC or adenoma, and of healthy individuals, clarify serum GRP's role in the development of CRC or adenoma.Methods: Cancer tissue and para-carcinoma tissue were collected from 50 cases of CRC, adenoma and normal tissue adjacent to adenoma were collected from 60 cases suffered from adenoma. Serum from patients with CRC(n=50) or adenoma(n=60) and healthy individuals(n=60) were collected. Immunohistochemistry(IHC) was used to detect the expression of GRP and GRPR in tissues. ELISA was adopted to detect the expression of GRP in serum. Chi-square test, ANOVA and independent sample T-test were used to analyze the data.Results:(1) Both GRP and GRPR were negative in all normal tissues, the positive expression rate of GRP and GRPR in CRC was 70.0%, 62.0%, and in adenoma tissue was 36.7%, 16.7%, respectively.(2) GRP expression in CRC tissues had no correlation to depth of invasion, the degree of tumor differentiation, lymph node metastasis, or tumor location(p >0.05), and no correlation to patients' age and gender(p >0.05). GRPR expression in CRC tissues hads certain relation to the degree of tumor differentiation(p <0.05), but no correlation to depth of invasion,, lymph node metastasis, or tumor location(p >0.05).(3) 46.0% of CRC cases had coexpression of GRP and GRPR, and the coexpression of GRP and GRPR was related to the degree of tumor differentiation, depth of invasion and lymph node metastasis(p <0.05), and no correlation to tumor location or patients' age and gender(p >0.05).(4) Expression of GRP and GRPR in adenoma was not related to adenomasize, pathologic type, the presence of intraepithelial neoplasia, or patients' age and gender(p >0.05).(5) GRP concentration in serum of CRC patients(1.40±0.15ng/m L) was significantly higher than that of adenoma patients and healthy volunteers(1.32±0.12ng/m L,1.31±0.12ng/m L, p <0.01), and the area under the ROC curve was 0.684, and sensibility was 48.0%, specificity was 84.2%. GRP concentration in serum of adenoma patients and healthy volunteers had no significant difference(p >0.05).Conclusion: GRP and GRPR were abnormally expressed in adenomatous polyps and CRC tissues, and coexpression of GRP and GRPR might be involved in the incidence, development and lymph node metastasis of CRC. GRP concentration in serum in the diagnosis of CRC with a certain value.