Objective: To study the expression of caspase recruitment domain family member 18 (CARD18) in apoptin-induced apoptosis of gastric cancer cells and its role in the development of gastric cancer.
Methods: After gastric cancer cells were transfected with apoptin, differentially expressed proteins between the apoptin-expression SGC7901 group and the control group were seperated using two-dimensional gel electrophoresis and identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and Mascot database (http: //www.matrixscience.com/). The expression level and location of CARD18 in 56 cases of gastric adenocarcinoma and adjacent cancer-free tissues were respectively detected by RT-PCR, Western blotting and immunohistochemistry to analyze the relationship between CARD18 and the clinical pathological characteristics.
Results: RT-PCR and Western blotting showed that the level of CARD18 mRNA and protein was down-regulated the most significantly after apoptin treatment. The expression of CARD18 in gastric adenocarcinoma tissues was significantly higher than that in adjacent cancer-free tissues (P<0.05), and it was proved that the CARD18 expression was related to the gastric cancer lymph node metastasis and TNM stage (P<0.05). CONCLUSION CARD18 may be both a promising marker for prognosis and a target protein for treatment of gastric cancer.