Detection of tumor cells in peripheral blood of patients with gastric cancer using mRNA of MAGE genes as markers / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To develop a sensitive and specific RT-PCR assay using the mRNA of MAGE-1 and MAGE-3 genes as specific tumor markers for the detection of the tumor cells in the peripheral blood of patients with gastric cancer.</p><p><b>METHODS</b>Peripheral blood was obtained from 40 patients with gastric cancer and from 20 healthy volunteers. The mRNA of MAGE-1 and MAGE-3 genes in the peripheral blood mononuclear cells (PBMC) was detected by RT-PCR. The expressions of MAGE-1 and MAGE-3 mRNA in the tumor tissues of these gastric cancer patients were also detected by RT-PCR. Meanwhile,CEA expression by nested RT-PCR in PBMC of 40 gastric cancer patients was also detected.</p><p><b>RESULTS</b>Of 40 gastric cancer patients, MAGE-1 and MAGE-3 mRNA were positive in 47.5% (19/40) and 25% (10/40) of PBMC respectively, and in 62.5% (25/40) and 30% (12/40) of gastric cancer tissues respectively. As a whole, in the PBMC of 40 gastric cancer patients, 25 (62.5%) samples were found to express at least one type of MAGE mRNA. In the patients whose tumors did not express MAGE-1 and/or MAGE-3 genes, the corresponding MAGE mRNA was also undetected in their PBMC. There was no expression of MAGE-1 or MAGE-3 gene in the PBMC from the 20 healthy donors. The positive rate of MAGE mRNA in PBMC was closely correlated with the tumor stage and lymph node metastasis (P <0.05). Positive rate of CEA gene expression was 32.5% (13/40) in the PBMC of 40 gastric cancer patients, 29 (72.5%)samples were detected to express at least one type of MAGE gene and CEA gene mRNA.</p><p><b>CONCLUSIONS</b>MAGE-1, MAGE-3 and CEA mRNA are specifically detected with high percentage in the PBMC of gastric cancer patients by RT-PCR. They could be used as specific tumor markers for the detection of the circulating gastric cancer cells, and the detection results may be helpful to evaluate the prognosis of gastric cancer patients.</p>

Effect of ACBP-S on cell cycle and apoptosis in human gastric cancer cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore the impact of anti-cancer bioactive peptide-S (ACBP-S) on cell proliferation, cell cycle and apoptosis in human stomach cancer cell line MGC-803 cells.</p><p><b>METHODS</b>(1) The cultured MGC-803 cells were treated with ACBP-S at various concentrations for 24, 48, 72 h, respectively. The inhibition rate of proliferation of MGC-803 cells were evaluated by MTT assay. Cell apoptosis was observed by transmission electron microscopy. Cell cycle and apoptosis were analyzed by flow cytometry (FCM). RT-PCR was used to assay the changes of p27 mRNA expression. Immunocytochemistry was used to detect the changes of expression of p27, PCNA, Bax, Bcl-2 proteins, respectively. (2) a nude mouse xenograft model with gastric carcinoma cell was established. ACPB-S was administered into the tail vein of the mice in a dose of 7 microg, every other day, and the mice were killed after two weeks. The tumors were taken off for further analysis.</p><p><b>RESULTS</b>(1) ACBP-S at concentrations of 5.0, 10.0 and 15.0 microg/ml inhibit the growth of MGC-803 cells in a concentration- and time-dependent manner. The concentration of ACBP-S at 20.0 microg/ml showed an inhibition rate of (86.6 + 0.1)%. Typical apoptotic changes were observed under the transmission electron microscope. The result of FCM in the range of 5.0 and 20.0 microg/ml for 24 h showed higher early apoptosis rates, (5.7 +/- 0.2)% and (13.9 +/- 0.6)%, respectively, with s significant difference compared with that of the control group (P < 0.05). The ratio of G0/G1 was significantly increased with the increase of incubation time at 20 microg/ml. RT-PCR showed that the expression of p27 mRNA in MGC-803 cells was markedly increased after ACBP-S treatment. (2) After ACBP-S administration the tumor growth in nude mice was inhibited by 34.2%. More apoptotic and necrotic cells were observed in the mice of treatment group by histological examination with HE staining. The immunocytochemistry demonstrated that the expression of Bax protein was significantly increased and Bcl-2 and PCNA protein expressions were significantly decreased after ACBP-S treatment.</p><p><b>CONCLUSION</b>ACBP-S has marked inhibiting effect upon the growth of MGC-803 cells inducing more apoptosis. The anti-cancer mechanism is probably related with its regulatory effects on cell cycle and apoptosis in the tumor cells.</p>

Application of Stream-media Transmission Technology in PACS and Distance Diagnosis / 医疗卫生装备

Objective To propose a stream-media technology based on the new transmission technology. Methods Firstly,we explored the advantages and disadvantages of exiting PACS image in LAN (Local Area Network) and WAN (Wide Area Network) and then expounded distance diagnosis related to HIS and PACS,VPN technology,wireless network applications,more points consultation applied technology. At last,we made an analysis of the characteristics of the stream-media transmission technology. Results The characteristics of low bandwidth occupied,high security,and high scalability of stream-media transmission technology fit the needs of PACS development. Conclusion Application of streammedia technology transferred in PACS image provides a new economical and practical technical solution to break through limitation of network bandwidth in medical imaging integrated information,and to thoroughly make use of medical resource.