Expression of costimulatory molecule B7-H4 on spleen lymphocytes during the progression of precancerous lesions in esophagus in mice

Objective: To investigate the percentages of splenic CD4+T, CD8+T and CD4+CD25+ forkhead-winged helix transcription factor 3 (foxp3)+ T regulatory cells and the expression of costimulatory molecule B7 homologue 4 (B7-H4) during different stages of progression of precancerous lesions in esophagus in mice. Methods: 4-Nitroquinoline-N-oxide (4NQO) in drinking water was used to induce esophageal precancerous conditions in mice. The hematoxylin-eosin (HE) staining was used to evaluate the pathological changes in different stages of precancerous conditions. The percentages of CD4+T, CD8+T and CD4+CD25+foxp3+ T regulatory cells in splenic lymphocytes and the positive rates of B7-H4 expression on CD4+T, CD8+T and CD4+CD25+foxp3+ T regulatory cells in mice in different stages of esophageal precancerous conditions were detected by flow cytometry (FCM). Results: At the time of the 12th week of giving 4-NQO in drinking water to induce esophageal cancer, the pathological abnormalities with low-grade intraepithelial neoplasia occurred in esophageal tissues in mice, and the high-grade intraepithelial neoplasia and carcinoma in situ were developed along with the time. The percentages of CD4+T and CD4+CD25+foxp3+ T regulatory cells in splenic lymphocytes in mice induced by drinking of 4-NQO were higher than those in the control mice (by drinking of distilled water) (both P < 0.01). As compared with the control mice, the positive rate of B7-H4 on the CD4+T cells in mice induced by drinking of 4-NQO was higher (P < 0.01) in a time-dependent manner (P < 0.05). Conclusion: Giving 4-NQO in drinking water can induce esophageal precancerous lesions in mice. CD4+T cells, T regulatory cells and B7-H4 may be involved in tumor immune escape mechanism. DOI:10.3781/j.issn.1000-7431.2014.11.432