Co-expression Of Guanylyl Cyclase-c And Caudal-type Homeobox Transcription Factor 2 In Human Gastric Cancer And Precursor Lesions

ObjectiveTo investigate the expression and significance of Guanylyl cyclase-C(GC-C) and caudal-type homeobox transcription factor 2 (CDX2) in human gastric tissues at different stages of cancerization.MethodsThe expression of GC-C and CDX2 in 30 cases of gastric carcinomas and the adjacent normal tissues was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) for mRNA and by Western Blot for protein. Also, by Indirect Immunofluorescence (IIF) methods, 23 cases of intestinal metaplasia, 9 cases of dysplasia, the gastric cancer and matching noncancerous tissues were analyzed for GC-C and CDX-2 protein.ResultsThe expression of GC-C mRNA and CDX-2 mRNA was absent in the normal mucosa in all cases, whereas, the GC-C mRNA and CDX2 mRNA expression were detected in 66.7% and 63.3% of gastric carcinomas cases respectively. GC-C and CDX-2 expressing in gastric carcinomas were more prevalent than in normal tissues. Moreover, expression of GC-C and CDX-2 showed a statistically significant difference between intestinal-type and diffuse-type gastric carcinoma(P<0.05). The results in gastric carcinomas for protein by Western Blot were similar. By Immunofluorescence methods, GC-C and CDX2 expression was detected in 39.1% and 39.1% of intestinal metaplasia cases, 55.6% and 55.6% of dysplasia cases, 56.7 % and 60.0 % of gastric carcinomas cases respectively. GC-C and CDX-2 expressing in intestinal metaplasia, dysplasia, and gastric carcinomas were more prevalent than in normal mucosa. Also, the positive correlation was found between GC-C and CDX2 in intestinal metaplasia and in gastric cancer.ConclusionsGC-C express in the early stage of human gastric cancer. Ectopic expression of GC-C in human gastric mucosa may play an important role in the carcinogenesis of the intestinal-type gastric carcinoma. CDX2 is important in initiation and development of gastric carcinoma and precursor lesions. Co-expression of GC-C and CDX2 in human gastric mucosa may ralate to the carcinogenesis of the intestinal-type gastric carcinoma, detection of GC-C and CDX2 will be beneficial to diagnosis human gastric cancer and precursor lesions.