Dynamic observation of intestinal epithelial stem cells of small intestine during the injured-repaired progress induced by 5-FU / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the dynamic changes of intestinal epithelial stem cells during the injured-repaired progress induced by 5-FU.</p><p><b>METHODS</b>Fifty adult C57BL/6J mice were enrolled in this study, 40 of them were intraperitoneally injected with 5-FU (30 mg per kg of body weigh) for five days, and 10 of them intraperitoneally injected with PBS as control. At day 1, 3, 5, 7 after treatment, the mice were killed and middle intestine was taken. Pathology was examined by HE staining. Musashi-1 (msi-1) expression was detected by immunohistochemical technique. The percentage of Rho low staining cells was detected by flow cytometry.</p><p><b>RESULTS</b>After treatment with 5-FU, the intestinal mucosa was damaged. The Rho low staining cells were increasing, and at day 1 after treatment, the percentage of Rho low staining cells reached the highest level (P<0.01). The number of cells expressing msi-1 did not change significantly (P>0.05), but the percentage of positive msi-1 cells increased significantly (P<0.01). There was positive correlation between the percentage of Rhodamine 123 low staining cells and positive msi-1 cells in each group (r=0.867, P<0.01).</p><p><b>CONCLUSIONS</b>The Rho low staining cells may contain rich intestinal epithelial stem cells. The intestinal epithelial stem cells expressing msi-1 can regenerate the damage of intestinal mucosa induced by 5-FU.</p>

Screening peptides binding specifically to large intestinal cancer LoVo cells from phage random peptide library / 南方医科大学学报

<p><b>OBJECTIVE</b>To screen the polypeptides specifically binding to human large intestinal cancer LoVo cells from a phage-displayed peptide library for potential use as targeting vectors for large intestinal cancer therapy.</p><p><b>METHODS</b>With the LoVo cells as the target cells and human normal large intestinal mucosal epithelial cells as the absorber cells for subtraction biopanning from a c7c phage-display peptide library, the positive phage clones were identified by enzyme-linked immunosorbent assay (ELISA) and immunofluorescence detection. The amino acid sequences of the identified peptides were deduced by DNA sequencing.</p><p><b>RESULTS</b>After 3 rounds of screening, 5 positive phage clones showing specific binding to LoVo cells and containing conserved motif RPMP were obtained from the 20 randomly selected clones.</p><p><b>CONCLUSION</b>Specific peptide against large intestinal cancer cells can be obtained from a phage-display peptide library for use as potential vectors for targeting therapy of large intestinal cancer.</p>

Expression of proliferating cell nuclear antigen in severely damaged small intestinal mucosa due to high-dose 5-FU exposure / 南方医科大学学报

<p><b>OBJECTIVE</b>To detect the expression of proliferating cell nuclear antigen (PCNA) in severely damaged intestinal mucosa due to high-dose 5-FU exposure.</p><p><b>METHODS</b>Thirty-two adult C57BL/6J mice were subjected to daily intraperitoneal high-dose 5-FU injection at 150 mg/kg for 5 consecutive days, and on days 1, 3, and 5, the mice were sacrificed to obtain the small intestinal tissue for HE straining and immunohistochemistry for detecting PCNA expression. Another 8 mice with intraperitoneal PBS injection served as the control group.</p><p><b>RESULTS</b>High-dose 5-FU exposure of the mice resulted in severe intestinal mucous damage, with complete destruction of the villi and crypts and significantly increased cells positive for PCNA expression (P<0.01).</p><p><b>CONCLUSION</b>High-dose 5-FU treatment can significantly increase the PCNA index, and the cells expressing PCNA can be closely associated with regeneration of the severely damaged mucosa due to the exposure.</p>

The expression of musashi-1 in small intestinal mucosa severely damaged by high dose 5-FU / 中国普通外科杂志

Objective To investigate the expression of musashi-1(msi-1)and its significances in small intestinal mucous severely damaged by high close 5-FU.Methods Total 40 adult C57BL/6J mice were divided into control group(n= 8,group D)and experimental group(n=32).Mice in control group received intraperitoneal injection of PBS as control,and mice in experimental group were intraperitoneally injected high dose 5-FU(150 mg per kg of body weigh for five days).After treatment 1 day(group A),3 days(group B)and 5 days( group C),the dying mice were killed,HE straining and immunohistochemical technique were carried out for detecting the expression of putative marker of intestinal epithelial stem cells——musashi-1(msi-1)in the samples of the meddle intestine,and the percentage of the msi-1 positive cells from the intestinal mucosal cells of the mice in group A was detected by flow cytometry.Results After the treatment of high dose 5-FU,the intestinal mucous was damaged severely;the number of msi-1 positive cells increased markedly;The intestinal mucosal cells can be divided into two groups by flow cytometry,and in the group in which the value of FSC was higher,the percentage of msi-1 positive cells increased to 67.75 %.Conclusions After the treatment of high dose of 5-FU,the percentage of intestinal stem cells increased significantly;this model may be useful for further isolation and enrichment of intestinal epithelial stem cells.