Expression of Maspin,uPA and MMP-7 in Human Gastric Carcinoma

Objective： To investigate the expression of maspin, uPA and MMP-7 in gastric carcinoma and discuss their roles in tumorigenesis and progression of gastric cancer. Methods： lmmunohistochemistry SP method was used to detect expression of maspin, uPA and MMP-7 in gastric adenocarcinoma （n=30）, signet-ring cell carcinoma （n=30）, normal gastric mucosa （n=20）; in addition, reverse transcriptase PCR was carried out to compare the mRNA expression of maspin between gastric adenocarcinoma and normal mucosa. Results： The expression rates of maspin, uPA and MMP-7 protein were 50%, 70% and 80% in gastric adenocarcinoma, and 46.7%, 76.7%, and 90% in signet-ring cell carcinoma, respectively. However, the expression rates of maspin, uPA, and MMP-7 protein were 90%, 35% and 30%, respectively in normal gastric mucosa. The relative transcription level of maspin mRNA in normal gastric mucosa was higher than that in gastric adenocarcinoma （P〈0.01）. Maspin protein expression was significantly related to the depth of invasion and lymph node metastasis of gastric carcinoma, but did not relate to tumor size and TNM staging. The protein expression of uPA and MMP-7 were significantly related to invasive depth, lymph node metastasis and TNM staging of carcinoma, but not to tumor size. Maspin protein expression had a negative correlation with uPA and MMP-7, while uPA protein expression had a positive correlation with MMP-7. The relative mRNA transcription level of Maspin significantly correlated with the lymph node metastasis and the depth of invasion of carcinoma, but did not relate to TNM staging or tumor size. Conclusion： Down-regulated expression of maspin and up- regulated expression of uPA and MMP-7 play important roles in the invasion and metastasis of gastric carcinoma. They may serve as effective markers of the biopathological behavior of gastric tumor.

Identification of differently expressed genes in human colorectal adenocarcinoma

AIM： To investigate the differently expressed genes in human colorectal adenocarcinorna.METHODS： The integrated approach for gene expression profiling that couples suppression subtractive hybridization, high-throughput cDNA array, sequencing, bioinformatics analysis, and reverse transcriptase real- time quantitative polymerase chain reaction （PCR） was carried out. A set of cDNA clones including 1260 SSH inserts amplified by PCR was arrayed using robotic printing. The cDNA arrays were hybridized with florescent-labeled probes prepared from RNA of human colorectal adenocarcinoma （HCRAC） and normal colorectal tissues.RESULTS： A total of 86 genes were identified, 16 unknown genes and 70 known genes. The transcription factor Sox9 influencing cell differentiation was downregulated. At the same time, Heat shock protein 10 KDis downregulated and Calmoulin is up-regulated.CONCLUSION： Downregulation of heat shock protein 10 KD lost its inhibition of Ras, and men attenuated the Ras GTPase signaling pathway, increased cell proliferation and inhibited cell apoptosis. Down-regulated transcription factor Sox9 influences cell differentiation and cell-specific gene expression. Down-regulated Sox9 also decreases its binding to calmodulin, accumulates calmodulin as receptor-activated kinase and phosphorylase kinase due to the activation of PhK.

Detection of Messenger RNA for Gonadotropin-Releasing Hormone (GnRH) but not for GnRH Receptors in Rat Pancreas

Although gonadotropin releasing hormone (GnRH), GnRH like molecule, and GnRH receptor (GnRH R) have been reported to exist in several tissues other than brain or anterior pituitary, there are no reports concerning GnRH or GnRH R gene expression in a normal pancreatic gland. In order to define the production of GnRH as well as GnRH R in the pancreatic gland, we examined their gene expression in various developmental stages of rat pancreas using the reverse transcriptase polymerase chain reaction (RT PCR). GnRH mRNA transcripts were found in pancreas of male and female rats at different ages, expressing at about the same level, whereas GnRH R mRNA transcripts could not be detected in any rat pancreatic gland samples. These results suggest a possible biological role of GnRH in rodent pancreas.