Effect of macrophages transduced with an adenoviral vector expressing interleukin-12 in prostate cancer

对于晚期前列腺癌，标准疗法是雄激素消融术，这在很大程度上是姑息性的，开发对全身性疾病有效的额外疗法来补充目前对局部前列腺癌的治疗是至关重要的。新的方法，如免疫基因治疗，为实现这些目标提供了机会。我们利用178-2 BMA小鼠前列腺癌模型研究了小鼠IL-12重组腺病毒载体（AdmIL-12）转导巨噬细胞的效果。admil -12转导的巨噬细胞在体外分泌IL-12，在任何MOI下细胞数量均无显著差异。未感染的巨噬细胞和adβ - gal感染的巨噬细胞在24小时和48小时产生非常低水平的IL-12，而在admil -12感染的巨噬细胞中检测到mIL-12分泌的剂量和时间依赖性增加。细胞分析显示，与未感染的巨噬细胞相比，admil -12感染的巨噬细胞表面MHC I类、II类分子和F4/80抗原的表达增加了2倍。ad β - gal感染的巨噬细胞与未感染的巨噬细胞相似，只是MHC II类表达增加。根据这些结果，我们已经成功地证明了用腺病毒载体对小鼠腹膜渗出巨噬细胞进行基因修饰，这种治疗方法有望诱导大量的全身抗肿瘤免疫反应。下一步，为了确定AdmIL-12转导的巨噬细胞可能的治疗活性，我们将使用转移性前列腺癌的原位小鼠模型建立临床前实验。

For advanced prostate cancer, the standard therapy is androgen ablation, which largely palliative and it is critical to develop additional therapies that are effective against systemic disease to complement current treatments for localized prostate cancer. Novel approaches, such as immunogene therapy, provide opportunities to achieve these goals.We investigated the efficacy of macrophages transduced with murine IL-12 recombinant adenoviral vector (AdmIL-12) using the 178-2 BMA mouse prostate cancer model. AdmIL-12-transduced macrophages secreted IL-12 in vitro and there were no significant differences in cell number at any MOI. Uninfected macrophages and Adβgal-infected macrophages produced very low levels of IL-12 at 24h and 48h, whereas a dose- and time- dependent increase in secretion of mIL-12 was detected in the AdmIL-12-infected macrophages. Cytometric analysis showed that AdmIL-12-infected macrophages had an 2 fold increase in surface expression of MHC class I and II molecules and F4/80 antigen compared with uninfected macrophages. Adβgal-infected macrophages were similar to uninfected macrophages except that increased MHC class II expression was observed. According to these results, we have demonstrated successful genetic modification of murine peritoneal exudates macrophages with adenoviral vectors and this therapeutic approach may induced substantial systemic antitumor immunological responses, hopefully. For next step to determine possible therapeutic activities AdmIL-12 transduced macrophages, we are going to set up preclinical experiment using an orthotopic mouse model of metastatic prostate cancer.