Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Department of Pathology and Pathophysiology, Shantou University Medical College, 22 Xinling Road, Shantou, Guangdong, 515041, China.
Curr Mol Med. 2013 Mar;13(3):429-37.
Recently immunoglobulin G (IgG) was found to be produced by neoplasms and promote tumor growth in cancer cell lines and animal models. To investigate the pathophysiological significance of cancer-produced IgG in breast cancer, we examined the expressions of IgG in 68 breast cancers including 40 primary cancers without metastasis and 28 cancers with axillary lymph node metastases. IgG gene expression was detected in all these samples. We found that IgG-expressing cancer cells were predominantly located in the periphery of the primary cancer nest and that these cells showed more cellular atypia and nuclear pleomorphism. We also found that the abundance of IgG-expressing cancer cells was higher and the cells were more evenly distributed in the metastatic cancer cells than that in the primary lesion. These findings suggest that IgG-expressing breast cancer cells have a more aggressive biological behavior than the IgG negative cancer cells and it could be an indicator for progression and metastasis of the disease. Co-localization of IgG and C1q complement was detected in both primary and metastatic lesions implying that immune complexes might be formed in situ. We speculate that such immune complexes might facilitate immune escape of cancer cells. Our findings suggest that locally produced IgG plays important roles in breast cancer, and may serve as a potential therapeutic target.
最近发现免疫球蛋白 G（IgG）由肿瘤产生，并在癌细胞系和动物模型中促进肿瘤生长。为了研究乳腺癌中肿瘤产生的 IgG 的病理生理意义，我们检测了包括 40 例无转移原发性癌症和 28 例腋窝淋巴结转移癌症在内的 68 例乳腺癌中的 IgG 表达。在所有这些样本中均检测到 IgG 基因表达。我们发现，表达 IgG 的癌细胞主要位于原发性癌巢的外周，这些细胞表现出更多的细胞异型性和核多形性。我们还发现，转移性癌细胞中表达 IgG 的癌细胞数量更多，分布更均匀，而原发性病变中的癌细胞数量较少，分布也不均匀。这些发现表明，表达 IgG 的乳腺癌细胞具有比 IgG 阴性癌细胞更具侵袭性的生物学行为，可能是疾病进展和转移的指标。在原发性和转移性病变中均检测到 IgG 和 C1q 补体的共定位，表明原位可能形成免疫复合物。我们推测，这种免疫复合物可能有助于癌细胞的免疫逃逸。我们的研究结果表明，局部产生的 IgG 在乳腺癌中发挥重要作用，可能成为潜在的治疗靶点。
