ABSTRACT
AIM: To study the expression levels of E- selectin, integrin beta1 and immunoglobulin superfamily member-intercellular adhesion molecule-1 (ICAM-1) in human gastric carcinoma cells, and to explore the relationship between these three kinds of cell adhesion molecules and gastric carcinoma. METHODS: The serum contents of E-selectin, integrin beta1 and ICAM-1 were detected by enzyme-linked immunosorbent assay (ELISA), in 47 healthy individuals (control group) and in 57 patients with gastric carcinoma (gastric carcinoma group) respectively prior to operation and 7 d after operation. RESULTS: The serum E-selectin, ECAM-1 and integrin beta1 were found to be expressed in both control and gastric carcinoma groups. However, they were highly expressed in patients with gastric carcinoma patients before operation or with unresectable tumours. The expression levels of ICAM-1 and integrin beta1 were significantly higher in gastric carcinoma patients than in controls (P < 0.01). A comparison of the E-selectin levels between the two groups showed statistically insignificant difference (P = 0.64). In addition, the expression levels were all decreased substantially in the postoperative patients subjected to radical resection of the tumours, indicating that the high level expressions of these compounds might be the important factor for predicting the prognosis of these patients. CONCLUSION: Serum E-selectin, ICAM-1 and integrin beta1 expression levels are probably related to the metastasis and relapse of gastric cancer.
Subject(s)
E-Selectin/genetics , Integrin beta1/genetics , Intercellular Adhesion Molecule-1/genetics , Stomach Neoplasms/genetics , Adult , Aged , Case-Control Studies , E-Selectin/blood , Enzyme-Linked Immunosorbent Assay , Female , Gene Expression Regulation, Neoplastic , Humans , Integrin beta1/blood , Intercellular Adhesion Molecule-1/blood , Male , Middle Aged , Neoplasm Recurrence, Local , Neoplasm Staging , Predictive Value of Tests , Prognosis , Stomach Neoplasms/blood , Stomach Neoplasms/pathology , Stomach Neoplasms/surgeryABSTRACT
AIM: To investigate the effect of arsenic trioxide on human gastric cancer cell line MKN45 with respect to both cytotoxicity and induction of apoptosis in vitro. METHODS: MKN45 cells were treated with arsenic trioxide (As2O3) at the concentration of 1, 5, and 10 micromol/L, respectively, for three successive days. Cell growth and proliferation were observed by cell counting and trypan blue exclusion. Cytotoxicity of As2O3 was determined by MTT assay. Morphologic changes were studied with light microscopy. Flow cytometry was used to assay cell DNA distribution and apoptotic cells were confirmed with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and DNA electrophoresis. RESULTS: The growth of MKN45 cells was significantly inhibited by As2O3 which was confirmed by colony-forming assay. After 7 d of culture with various concentrations of As2O3, colony-forming capacity of MKN45 cells decreased with As2O3 increment in comparison with that of control group. The inhibitory rate of colony-formation was 38.5%, 99.1%, and 99.5% when the concentration of As2O3 was 1, 5, and 10 micromol/L in culture medium, respectively. The cell number of a single colony in drug treatment groups was less than that of control group. The cell-killing rate of As2O3 to MKN45 cells was both dose- and time-dependent with an IC50 of (11.05+/-0.25) micromol/L. After incubation in 10 micromol/L As2O3 for 24 h, the cell-killing rate was 27.1%, and it was close to 50% after 48 h. The results showed that As2O3 induced time- and dose-dependent apoptosis in MKN45 cells, blocked at G2/M phase. The apoptotic peak (sub-G1 phase) appeared and cell apoptotic rate in MKN45 cells was 18.3-32.5% after treatment by 10 micromol/L As2O3 for 48 h. The percentage of G2/M cell of the experimental groups was 2.0-5.0 times than that of the control group. Gel electrophoresis of DNA from cells treated with each concentration of As2O3 for 48 h revealed a "ladder" pattern, indicating preferential DNA degradation at the internucleosomal, linker DNA sections. TUNEL also demonstrated strand breaks in DNA of MKN45 cells treated with As2O3, while control cells showed negative labeling. CONCLUSION: As2O3 can induce apoptosis of human gastric carcinoma cells MKN45, which is the basis of its effectiveness. It shows great potential in the treatment of gastric carcinoma.