ABSTRACT
Objective To study the infection rate of fusobacterium nucleatum cancer re appeared in patients with colorectal cancer before and after radiotherapy,and the changes after cancer recarrence.Methods A total of 20 persons receiving physical examination were recruited in the control group and collected the stool specimens,and 40 colorectal cancer patients were selected in the study group.All of the subjects in the study group were collected stool specimens before operation 3 days and after operation 5 day,after radiation therapy 7 days and 30 days.The patients were followed-up 1 year.The bacterial fluid was collected by filtration,and real-time fluorescence quantitative PCR was used to detect the expression of fusobacterium nucleatum gene in feces.Results The positive rate of fecal fusobacterium fusiformis was 30% in the study group and 5% in the control group.The gene relative expression of 12 colorectal cancer patients before operation 3 days and after operation 5 days,after radiation therapy 7 days and 30 days were 5.20±0.34,8.50±0.45,1.20±0.22,0.20±0.15.The fusobacterium nucleatum gene expression of 12 patients with positive fusobacterium after operation 5 days was significantly increased compared with that before operation 3 days(t=10.419,P=0.001),which after radiation therapy 7 days and 30 days was significant lower than that before operation 3 days(t=12.728,P=0.001;t=25.889,P=0.001).Six patients recurred among 1 year,the fusobacterium nucleatum gene expression was 7.2±0.56,which was significant higher than that after radiation therapy 7 days.Conclusion The infection of fusobacterium nucleatum might be a risk factor for colorectal cancer,and the gene relative expression might be an early warning indicator of recurrence.
ABSTRACT
BACKGROUND:Human amniotic epithelial cells are an important source of cells in regenerative medicine as its multipotentation, but new studies mainly focused on differentiation features and there were little research oneffect of culture in vitro on biological property of amniotic epithelial cells. OBJECTIVE:To analyze the effects of in vitro culture on growth, cellphenotype and differentiation capacity of human amniotic epithelial cells into cardiomyocyte-like cells, and explore the correlation of primarily cultured human amniotic epithelial cells marker SSEA-4 expression level and the change of biological characteristics of human amniotic epithelial cells. METHODS:Primarily cultured human amniotic epithelial cells were obtained from amniotic tissues by using the same separation protocol. Human amniotic epithelial cells were cultured in vitro. The proliferation, cellphenotype and the differentiation capacity of human amniotic epithelial cells into cardiomyocyte-like cells were evaluated by means of cellcounting kit-8, flow cytometry and real-time PCR. RESULTS AND CONCLUSION:The SSEA-4 positive cells in primarily cultured human amniotic epithelial cells from different fetal tissues were between 26.7%-97%, which indicated that there was great individual difference among amniotic tissue samples. Moreover, with passage, the SSEA-4 expression in human amniotic epithelial cells decreased significantly, which did not correlate with the SSEA-4 expression in primarily cultured human amniotic epithelial cells. Results indicated that there was great individual difference in SSEA-4 expression level in primarily cultured human amniotic epithelial cells from different amniotic tissue samples. Thus, it is necessary to set up clinical screening indexes to get samples with higher SSEA-4 expression stably and to control the quality of human amniotic epithelial cells. In addition, during culture period, SSEA-4 expression level was affected by culture conditions. The culture conditions of human amniotic epithelial cells should be optimized to maintain SSEA-4 expression at a high level. In addition, the differentiation capacity of human amniotic epithelial cells into cardiomyocyte-like cells was also affected by individual difference among different samples and culture conditions, which wil be further studied in the future.