B淋巴细胞在胃癌中的分布、表型及与胃癌进展相关性初步研究

Distribution, phenotype, and clinical relevance of B lymphocytes in gastric cancer

目的分析胃癌患者与健康人外周血、胃癌组织及正常组织中的B淋巴细胞(B细胞)的分布情况以及胃癌微环境中B细胞的表型特征;探讨胃癌组织中浸润B细胞与胃癌患者临床分期的相关性。方法采用流式细胞术检测并分析胃癌患者外周血中以及胃癌组织中CD20+B细胞的频率以及B细胞在胃癌微环境中的表型;同时采用免疫组化染色技术检测B细胞在组织中的浸润情况并分析胃癌组织中B细胞的数量与胃癌患者临床分期的相关性。结果在胃癌患者、健康人外周血以及胃癌组织与正常组织中,CD20+B细胞的频率均无显著差异(P>0.05);与胃癌患者正常组织相比,胃癌组织中CD20+B细胞数量显著增加,具有显著统计学差异(P<0.01)。表型分析显示胃癌组织中B细胞表达Ig D、Ig M、Ig G,高表达CD40、HLA-DR、HLA-ABC,低表达CD80、CD86。此外,与晚期胃癌相比,早期胃癌肿瘤组织中浸润的CD20+B细胞数显著增加(P<0.01)。结论 B细胞在胃癌微环境中浸润显著增加,其在早期胃癌患者肿瘤组织中的浸润数目显著多于晚期胃癌患者,提示B细胞在胃癌进展中可能发挥一定的免疫调控作用。

To investigate the infiltration of B lymphocytes（B cells） in tumor tissues and the clinical relevance of B cells in gastric cancer（GC） patients, we analyzed the distribution and phenotypic characteristics of B cells in peripheral blood of healthy donors and GC patients, and in normal tissues and tumor tissues of GC patients. Flow cytometry was used to detect and analyze the frequency of CD20＋B cells in lymphocytes in tumor tissues and peripheral blood of GC patients, and the phenotype of CD20＋B cells in tumor tissues from GC patients;immunohistochemical staining were applied to investigate the infiltration of B cells in tumor tissues of GC patients.Then the relationship between the number of B cells in tumor tissues and tumor progression of GC patients was also investigated. Data showed that there was no significant difference in B cells frequency in peripheral blood between GC patients and healthy donors（P 〉 0.05）, as well as between normal tissues and tumor tissues of GC patients（P 〉0.05）. Moreover, the number of B cells was significantly higher in tumor tissues than that in non-tumor tissues（P 〈0.01）. In tumor tissues, B cells expressed Ig D, Ig M, Ig G, and high level of CD40, HLA-DR, HLA-ABC, but low level of CD80, CD86. In addition, the number of tumor-infiltrating B cells was significantly higher in GC patients with early stages than that with advanced stages（P 〈 0.01）. In conclusion, B cells are enriched in GC tumor tissues and are significantly higher in GC patients with early stages than that with advanced stages, suggesting that B cells may play an immunoregulatory role in GC.