Progress, challenges and new genome-based concepts in the multidisciplinary treatment of gastric cancer

miR-449a and CDK6 in gastric carcinoma

The present study aimed to identify the association between microRNA (miR/miRNA)-449a, the cyclin-dependent kinase (CDK)6 protein and gastric carcinoma, and discuss the effect of miR-449a on the expression of the CDK6 protein. Quantitative (q)PCR and western blot analysis were used to analyze the expression of the miR-449a and the CDK6 protein in gastric carcinoma and tumor-adjacent normal tissues. The real-time cell analyzer and the DAPI staining test were used to monitor the different miR-449a levels regulating the proliferation and apoptosis of the MGC-803 cell line. Immunofluorescence and western blot analyses were used to detect the expression level of the CDK6 protein in the cells of the miR-449a upregulation and downregulation groups, and a control group. A scratch test was used to study the effects of miR-449a expression on migration and invasion. It was found that the expression of miR-449a was downregulated and the expression of CDK6 protein was upregulated in gastric carcinoma tissue. The level of MGC-803 cell proliferation was decreased and the apoptosis level was increased by the upregulation of miR-449a expression, and the opposite effect was shown by the downregulation of expression. The expression of the CDK6 protein in the MGC-803 cells was downregulated by upregulating the expression of miR-449a. The distance of the scratch was shortened markedly after 12 h by downregulating the expression of miR-449a in the MGC-803 cells. The present study identified that a lower expression level of miR-449 and a higher expression level of CDK6 may contribute to the occurrence and development of gastric cancer. Furthermore, it was shown that miR-449a is able to regulate the expression of the CDK6 protein.

Prognostic factors and outcomes in Italian patients undergoing curative gastric cancer surgery

BACKGROUND

Survival of patients after curative surgical resection for gastric cancer (GC) remains poor, thus emphasizing the need for better definition of prognostic factors to improve the long-term course of disease.

METHODS

From 1999 to 2009, 110 patients had curative-intent gastrectomy for adenocarcinoma. Clinicopathological features, Helicobacter pylori infection, dietary habits and lifestyle, and the presence of proinflammatory gene polymorphisms were evaluated.

RESULTS

At the end of follow-up, 55 deaths had occurred, 48 of them due to GC, whereas the median overall survival (OS) and disease-free survival (DFS) were 62 and 51 months, respectively. From the Kaplan-Meier analysis and log-rank test, statistically significant differences in OS and DFS were found for tumor site (only for DFS), tumor size, lymph node metastasis ratio (NR), and tumor-node-metastasis stage, but not for age, comorbidity, H. pylori infection, cigarette smoking, and IL1B or TNFA polymorphisms. Multivariable Cox regression analysis revealed NR was an independent prognostic factor for OS and DFS. Cardia tumor and patient age 65 years or older were also independent prognostic factors for OS and DFS.

CONCLUSIONS

Tumor-related factors remain strongest predictors of survival in GC patients after surgery. Particularly, NR was an effective feature in identifying patients at high risk for adverse outcome.