Pupa Serenella M, Iezzi Manuela, Di Carlo Emma, Invernizzi AnnaMaria, Cavallo Federica, Meazza Raffaella, Comes Alberto, Ferrini Silvano, Musiani Piero, Ménard Sylvie
Molecular Targeting Unit, Department of Experimental Oncology, Istituto Nazionale Tumori, Via Venezian 1, 20133 Milan, Italy.
Cancer Res. 2005 Feb 1;65(3):1071-8.
Plasmid DNA vectors encoding the full-length (VR1012/HER-2-FL) or only the extracellular and transmembrane domains (VR1012/HER-2-ECD-TM) of human (h) HER-2/neu proto-oncogene were used to vaccinate HER-2/neu transgenic mice (N202) engineered to overexpress the rat (r) neu proto-oncogene product (r-p185(neu)). Both the full-length and the deleted vaccines were significantly (P = 0.0001 and P = 0.06, respectively) more active than the empty vector (VR1012/EV) in preventing and delaying HER-2/neu-driven mammary carcinogenesis. A low-level intratumoral infiltrate of dendritic cells, macrophages, CD8 T cells and polymorphonuclear granulocytes in association with low-level cytokine production was observed, which was not detected in tumors from control mice. Morphologic analyses showed that vaccination with VR1012/HER-2-FL or ECD-TM also efficiently hampered the development of terminal ductal lobular units (TDLU). Analyses of sera from vaccinated mice revealed high titers of antihuman HER-2/neu antibodies, which correlated with the delayed time of tumor onset (P = 0.002). These antibodies did not cross-react with r-p185(neu). Nontransgenic mice treated with the vaccines produced autoreactive antibodies targeting mouse (m)-p185(neu) and showed impaired function of the lactating mammary gland and accelerated involution of the gland after weaning. Together, these data indicate that xenogeneic DNA immunization breaks tolerance against the endogenous m-p185(neu), impairing the development of mammary TDLU in which m-p185(neu) expression is concentrated. The reduction in the number of TDLU decreases the number of glandular structures available for r-p185(neu)-dependent mammary carcinogenesis, resulting in a significant inhibition of mammary carcinoma development.
编码人(h)HER-2/neu原癌基因全长(VR1012/HER-2-FL)或仅细胞外和跨膜结构域(VR1012/HER-2-ECD-TM)的质粒DNA载体,用于给经基因工程改造以过表达大鼠(r)neu原癌基因产物(r-p185(neu))的HER-2/neu转基因小鼠(N202)接种疫苗。在预防和延缓HER-2/neu驱动的乳腺癌发生方面,全长疫苗和缺失疫苗均比空载体(VR1012/EV)显著更具活性(分别为P = 0.0001和P = 0.06)。观察到肿瘤内有低水平的树突状细胞、巨噬细胞、CD8 T细胞和多形核粒细胞浸润,并伴有低水平的细胞因子产生,而在对照小鼠的肿瘤中未检测到这种情况。形态学分析表明,用VR1012/HER-2-FL或ECD-TM接种疫苗也能有效阻碍终末导管小叶单位(TDLU)的发育。对接种疫苗小鼠血清的分析显示,抗人HER-2/neu抗体滴度很高,这与肿瘤发病时间的延迟相关(P = 0.002)。这些抗体与r-p185(neu)无交叉反应。用疫苗处理的非转基因小鼠产生了靶向小鼠(m)-p185(neu)的自身反应性抗体,并表现出泌乳乳腺功能受损以及断奶后乳腺加速退化。总之,这些数据表明异种DNA免疫打破了对内源性m-p185(neu)的耐受性,损害了m-p185(neu)表达集中的乳腺TDLU的发育。TDLU数量的减少降低了可用于r-p185(neu)依赖性乳腺癌发生的腺结构数量,从而显著抑制了乳腺癌的发展。