Identification Of Label Retaining Cells In Mouse Laryngeal Mucosa And Laryngocarcinoma

【OBJECTIVE】To identify the existence of stem cells and its distribution in mouse laryngeal mucosa and laryngocarcinoma by using the label–retaining cells with bromodeoxyurdine(BrdU).【METHODS】36 Kunming white mice after born three days were randomly divided into two groups, 18 mice in each group. Intraperitoneally injected BrdU 50μg/g in experiment group and 0.9% NS in control group twice daily and totally injected 3d. Put mice death after injected 2w, 4w and 8w, each time 6 mice in each group, fixed the laryngeal mucosa for immunohistochemistry and calculated the percentages of label-retaining cells. A Hep-2 cell line of laryngocarcinoma was labeled with BrdU in vitro and then engrafted into back of 6 nude mice, which developed tumors. Put nude mice death after injected 8w, fixed the tumors for immunohistochemistry and pathology.【Results】There were label–retaining cells in scalyepithelium and gland epithelium after 2w, 4w, 8w labeling. The expression of label–retaining cells was not observed in control group. The percentages of label–retaining cells in different phase of scalyepithelium and gland epithelium were significance (F=140.319,208.382 ;P=0.000,0.000) . The percentages of label–retaining cells in stratum basale of scalyepithelium were higher than that in gland epithelium at each phase(t=6.376,10.944,15.376; P=0.000,0.000,0.000). Label–retaining cells were detected in laryngocarcinoma after 8w in nude mice.【CONCLUSION】There are label–retaining cells in the mouse laryngeal mucosa and laryngocarcinoma. It is possible that stem cells exist in these LRCs.