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目的：克隆酪氨酸酶（Ｔｙｒ）启动子并探索其调控细菌胞嘧啶脱氨酶（ＣＤ）在黑色素瘤基因治疗中的应用价值。方法：用ＰＣＲ法从小鼠恶性黑色素瘤细胞Ｂ１６基因组中克隆Ｔｙｒ启动子片段并与正常序列比较，并于逆转录病毒载体Ｇ１Ｎａ中调控ＣＤ基因（ＴｙｒＣＤ）。测体外表达和体内抗肿瘤作用。结果：来源于Ｂ１６基因组的Ｔｙｒ启动子重要反式作用位点未见突变。该Ｔｙｒ启动子可使ＣＤ基因在Ｂ１６中特异表达。转ＴｙｒＣＤ的Ｂ１６可以抑制亲代细胞的成瘤作用。含ＴｙｒＣＤ的重组病毒可在体内感染黑色素瘤细胞和骨髓细胞。体内注射５氟胞嘧啶后可使黑色素瘤消退，并对骨髓细胞有保护作用。结论：来源于正常组织或肿瘤组织的Ｔｙｒ启动子指导的ＣＤ基因在恶性黑色素瘤ｉｎｖｉｖｏ基因治疗方面是安全、有效的
Objective: To clone tyrosinase (Tyr) promoter and explore its application in the regulation of bacterial cytosine deaminase (CD) in melanoma gene therapy. METHODS: The Tyr promoter fragment was cloned from the B16 genome of mouse malignant melanoma cells by PCR and compared with the normal sequence. The TyrCD gene was regulated in the retroviral vector G1Na. In vitro expression and in vivo anti-tumor effects were measured. RESULTS: There were no mutations in the important trans-acting sites of the Tyr promoter derived from the B16 genome. The Tyr promoter allows the specific expression of the CD gene in B16. B16 transfected with TyrCD can inhibit the tumorigenesis of parental cells. The TyrCD-containing recombinant virus can infect melanoma cells and bone marrow cells in vivo. In vivo injection of 5-fluorocytosine can cause melanoma regression, and has a protective effect on bone marrow cells. Conclusion: The Tyr promoter-directed CD gene derived from normal tissues or tumor tissues is safe and effective in malignant melanoma invivo gene therapy.