Association of Bmi-1 mRNA expression with differentiation, metastasis and prognosis of gastric carcinoma / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the association of B cell-specific MLV integration site-1 (Bmi-1) mRNA expression level with the differentiation, metastasis and prognosis of gastric carcinoma.</p><p><b>METHODS</b>Tissue specimens were obtained from 42 patients undergoing surgery for gastric carcinomas. Reverse transcriptional PCR (RT-PCR) was performed for amplification of Bmi-1 mRNA from the 42 tumor tissues and matched adjacent normal tissues, and the differential Bmi-1 mRNA expression was analyzed for its association with the clinical manifestations of the patients.</p><p><b>RESULTS</b>Bmi-1 mRNA expression was detected in all the gastric carcinoma tissues and normal tissues adjacent to the carcinoma using fluorescence method, and in 29 cases, Bmi-1 mRNA expression was significantly higher in the tumor tissues than in the adjacent tissues. Expression of Bmi-1 mRNA was highly correlated with tumor size, lymph node metastasis and T classification (P<0.05), but not with the patients' gender, age, or tumor differentiation (P>0.05). The survival rate was much lower in patients positive for Bmi-1 mRNA expression than in those without Bmi-1 mRNA expression.</p><p><b>CONCLUSIONS</b>Bmi-1 mRNA expression is correlated to differentiation and metastasis of gastric carcinoma and may facilitate its prognostic evaluation. Bmi-1 may serve as a marker for assessing the progression of gastric carcinoma and provide assistance for clinical therapeutic decisions.</p>

Biodistribution of (99m)Tc-labeled anti-VEGF mAb 5-FU loaded polylactic acid nanoparticles in human gastric carcinoma xenografts / 南方医科大学学报

<p><b>OBJECTIVE</b>To prepare (99m)Tc-labeled Anti-VEGF mAb 5-FU loaded polylactic acid nanoparticles ((99m)Tc-Ab-5-FU-NPs) and investigate its biodistribution in human gastric carcinoma xenografts.</p><p><b>METHODS</b>(99m)Tc-Ab-5-FU-NPs were prepared by labeling Ab-5-FU-NPs with (99m)Tc using improved Schwarz method. After isolation of (99m)Tc-Ab-5-FU-NPs using SephadexG250 column, the labeling ratio and radiochemical purity were determined using chromatography. The immunocompetence of (99m)Tc- Ab-5-FU-NPs was detected by ELISA and immunohistochemistry. (99m)Tc-Ab-5-FU-NPs were then injected via the tail vein into SCID mice bearing human gastric carcinoma, and (99m)Tc labeled mice-derived monoclonal IgG loaded polylactic acid nanoparticles were used as the control, followed by radioimmunoscintigraphic imaging at 2 and 6 h. The radioactive count and radioactive ratio of the tumor and non-tumor tissue (T/NT) in the animal models were calculated using ROI technique. After imaging at 24 h, SCID mice were sacrificed and the radioactive distribution, the %ID/g, as well as the T/NT radioactive ratio were examined, respectively. The concentrations of 5-FU in the tumor and blood were also detected using HPLC method.</p><p><b>RESULTS</b>The labeling ratio of (99m)Tc-Ab-5-FU-NPs was 90%-95%. (99m)Tc-Ab-5-FU-NPs were detected in the tumor tissues by radioimmunoimaging 2 h after the injection. ID%/g in the tumor tissues at 2 and 6 h were both significantly higher than that of the control group. Both the ID%/g in tumor tissues and radioactive ratio of tumor and blood at 6 h were higher than those at 2 h, and the concentration of 5-FU in experimental group increased continuously with time and was significantly higher than that in control group.</p><p><b>CONCLUSIONS</b>(99m)Tc-Ab-5-FU-NPs prepared in this study can meet the demands of radioimmunoimaging, and the anti-VEGF monoclonal antibody possesses reliable immune targeting ability. Six hours after injection, (99m)Tc-Ab-5-FU-NPs can specifically accumulate in the tumor tissues in human gastric carcinoma xenografts at high concentration.</p>