Sypniewska Roza K, Hoflack Lieve, Tarango Melissa, Gauntt Susan, Leal Belinda Z, Reddick Robert L, Gravekamp Claudia
Department of Cellular and Structural Biology, University of Texas Health Science Center, STCBM building, 15355 Lambda Drive, San Antonio, TX 78245, USA.
Breast Cancer Res Treat. 2005 May;91(1):19-28. doi: 10.1007/s10549-004-6454-7.
Anti-tumor vaccines are a relatively non-toxic alternative to conventional chemotherapeutic strategies to control breast cancer. Immunization with tumor-associated antigens (TAAs) triggers anti-tumor cytotoxic T lymphocytes (CTL), which can limit tumor progression. Here we report on the development and effectiveness of a TAA-based DNA vaccine encoding Mage-b1/2, the mouse homologue of the human MAGE-B1/2. As model system, we used immune competent Balb/c mice with syngeneic non-metastatic (64pT) or metastatic (4TO7cg) breast tumors. First, the presence of Mage-btranscripts in the 64pT and 4TO7cg breast tumors and metastases was demonstrated by RT-PCR, Southern blotting, and DNA sequencing. A DNA-based vaccine was developed from transcripts of one of the 64pT tumors, encoding the complete Mage-b1/2 protein, and subsequently tested for its preventive efficacy in both breast tumor models. Mice were immunized two times intramuscularly with the vaccine (pcDNA3.1-Mage-b1/2-V5), the control vector (pcDNA3.1-V5), or saline. Two weeks after the last immunization, the syngeneic 4TO7cg or 64pT tumor cell lines were injected in a mammary fat pad. Mice were monitored during the next 4 weeks for tumor formation, latency and size, and subsequently sacrificed for analysis. While the Mage-b1/2 vaccine had only a minor effect on the latency and growth of primary tumors, a significant and reproducible reduction in the number of 4TO7cg metastases was observed (vaccine versus control vector, p=0.0329; vaccine versus saline, p=0.0128). The observed protective efficacy of the Mage-b DNA vaccine correlated with high levels of vaccine-induced IFNgamma in spleen and lymph nodes upon re-stimulation in vitro. These results demonstrate the potential of TAA-based DNA vaccines in controlling metastatic disease in breast cancer patients.
抗肿瘤疫苗是控制乳腺癌的一种相对无毒的替代传统化疗策略的方法。用肿瘤相关抗原（TAA）进行免疫接种可触发抗肿瘤细胞毒性T淋巴细胞（CTL），从而限制肿瘤进展。在此，我们报告一种基于TAA的DNA疫苗的研发及其有效性，该疫苗编码人MAGE-B1/2的小鼠同源物Mage-b1/2。作为模型系统，我们使用具有免疫活性的同基因Balb/c小鼠，其携带同基因的非转移性（64pT）或转移性（4TO7cg）乳腺肿瘤。首先，通过RT-PCR、Southern印迹和DNA测序证明了Mage-b转录本在64pT和4TO7cg乳腺肿瘤及转移灶中的存在。从64pT肿瘤之一的转录本开发了一种基于DNA的疫苗，其编码完整的Mage-b1/2蛋白，随后在两种乳腺肿瘤模型中测试其预防效果。用该疫苗（pcDNA3.1-Mage-b1/2-V5）、对照载体（pcDNA3.1-V5）或生理盐水对小鼠进行两次肌肉注射免疫。最后一次免疫两周后，将同基因的4TO7cg或64pT肿瘤细胞系注射到乳腺脂肪垫中。在接下来的4周内监测小鼠的肿瘤形成、潜伏期和大小，随后处死小鼠进行分析。虽然Mage-b1/2疫苗对原发性肿瘤的潜伏期和生长仅有轻微影响，但观察到4TO7cg转移灶数量有显著且可重复的减少（疫苗与对照载体相比，p = 0.0329；疫苗与生理盐水相比，p = 0.0128）。在体外重新刺激后，观察到的Mage-b DNA疫苗的保护效果与脾脏和淋巴结中疫苗诱导的高水平IFNγ相关。这些结果证明了基于TAA的DNA疫苗在控制乳腺癌患者转移性疾病方面的潜力。
