Objective To investigate the relationship between standard CD44(CD44s)expression and tumor stage and prognosis in colorectal cancer.Methods CD44s expression was detected by immunohistochemistry in tumor tissues and normal mucosa specimens from 74 cases of primary colorectal cancer.Results Of 74 cases,the expression of CD44s in colorectal cancer tissue and normal mucosa specimens was documented in 42% and 16%,respectively.The expression of CD44s in primary tumors significantly increased in stage Ⅲ and Ⅳ than in stage Ⅰ and Ⅱ(39% vs.6%,x~2=8.46,P＜0.01).A statistically significant correlation was observed between the overall survival and CD44s expression(x~2=17.82,P＜0.01).Furthermore,a poor prognosis of CD44s-positive tumors was observed in patients with stage Ⅲ and Ⅳ colorectal cancer(x~2=16.23,P＜0.01),but not in patients with stage Ⅰ and Ⅱ colorectal cancer(x~2=1.34,P＞0.05).Multivariate analysis indicated that TNM stage and CD44s expression were independent predictors of overall survival in colorectal cancer.Conclusion CD44s overexpression is involved in the progress of colorectal cancer and predicting the prognosis.

Objective To explore the clinical pathological features of gastric cancer and to provide a basis for research and treatment of gastric cancer.Methods From 2001 to 2004,a total of 694 cases of gastric cancer with radical gastrectomy were collected.Gender,age,tumor location,tumor size,World Health Organization (WHO) histological type and grade,Lauren type,blood/lymphatic vessel invasion,lymph node metastasis,depth of tumor invasion (pT) and pathological TNM staging (pTNM) were retrospectively analyzed.Results Among 694 gastric cancer cases,male to female ratio was 3.96∶ 1; a total of 644 cases (92.8％) were aged from 41 to 70,and cases aged from 51 to 70 had a high incidence of gastric cancer.The predilection site for gastric cancer was cardia (33.43％),antrum (28.96％) and the body (21.76％) accordingly.The common WHO histological types were tubular adenocarcinoma (70.32 ％) and signet ring cell carcinoma (24.50 ％).The common histological grades were Ⅱ,Ⅲ and Ⅰ.The intestinal type was most common in Lauren classification,accounting for 58.93 ％; followed by the diffuse type,accounting for 22.33 ％.Blood/lymphatic vessel invasion was detected in 438 cases (63.11％),lymphnode metastasis in 504 cases (72.62％).A total of 319 cases (45.97％) were pT3 stage,241 cases (34.73％) were on pTNM Ⅲ stage.Conclusions In recent years,cardia and antrum are the predilection sites of gastric cancer.Tubular adenocarcinoma and signet ring cell carcinoma are common which indicate that the mechanism of gastric cancer pathogenesis is varied.

Objective To identify biomarkers associated with the differentiated phenotype based on gene expression profiling of gastric cancer. Methods Two bioinformatic methods, BAGEL and k-TSP, were used to identify featured genes associated with differentiation in gastric cancer samples based on the Oligo gene chip data, and ROC curves were used to verify the classification sensitivity and specificity of the identified genes. Finally, a total of 30 gastric cancer samples with different differentiation levels were collected for laboratory validation using real-time PCR analyses. Results A total of 121 differentially expressed genes were identified using the BAGEL algorithm, the criterion were FC ＞ 2. 0 and P ＜ 0. 001.Then, the k-TSP algorithm for feature selection based on this differential expression data were used, and 3 groups of featured genes which had potential to classify poor and well differentiation gastric cancer samples were identified, including MYLIP and TMPRSS3, ZNF266 and TM4SF1, SNAI2 and CNFN. To define the featured gene groups that had the highest classification capability, ROC curves to calculate the classification sensitivity and specificity of each gene group were used. The results showed that the combination of SNAI2and CNFN as a classifier had the highest classification sensitivity and specificity. Real-time PCR results showed that 18 of 22 poor differentiation samples were found with high expression of SNAI2 and low expression of CNFN (82%); 6 of 8 well differentiation samples were of low expression of SNAI2 and high expression of CNFN (75%). Conclusion The results indicate that SNAI2 and CNFN are constantly expressed in poor or well differentiation gastric cancer samples, and the expression pattern of these two genes is opposite. These results indicate that SNAI2 and CNFN have the potential for the identification of the differentiation level of gastric cancer.