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>