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构建了由人胰蛋白酶抑制剂基因的增强子（称为ＡＴ）和大鼠ａｆｐ基因启动子与沉默子（称为ｒＰＳ）组成的杂合基因表达调控序列（命名为ＡＴｒＰＳ）；还构建了１．２ｋｂ的由大鼠ａｆｐ基因增强子ＩＩ和ｒＰＳ组成的调控序列（命名为ｒＡＦＰ）。将报告基因－氯霉素乙酰转移酶基因（ｃａｔ）置于这些序列控制之下，构建成ＣＡＴ表达载体Ａ－ＴｒＰＳ－ｐＣＡＴ和ｒＡＦＰ－ｐＣＡＴ。在甲胎蛋白（ＡＦＰ）阳性的肝癌细胞或ＡＦＰ阴性的肝癌细胞、肝细胞以及非肝细胞中检测ＣＡＴ活性。结果，在ＡＦＰ阳性的肝癌细胞中两种载体都能产生ＣＡＴ活性，而在ＡＦＰ阴性的肝癌细胞、正常肝细胞和非肝细胞中均无活性，特别是在原代细胞中也得到相同结果。从而证实这些基因表达调控序列具有ＡＦＰ阳性肝癌细胞的专一表达活性。如果将ｒＡＦＰ缩短至０．６７ｋｂ，它仍然保持了很好的细胞专一性及较高的活性。这些基因调控序列可望用于原发性肝细胞癌的专一性基因治疗
A hybrid gene expression regulatory sequence (designated as ATrPS) consisting of an enhancer (called AT) of the human trypsin inhibitor gene and a promoter (a) of the rat afp gene (called rPS) was constructed; The .2 kb regulatory sequence (designated rAFP) consisting of rat afp gene enhancer II and rPS. The reporter gene-chloramphenicol acetyltransferase gene (cat) was placed under the control of these sequences to construct CAT expression vectors A-TrPS-pCAT and rAFP-pCAT. CAT activity was detected in alpha-fetoprotein (AFP) positive liver cancer cells or AFP negative liver cancer cells, liver cells, and non-hepatocytes. As a result, both vectors were capable of producing CAT activity in AFP-positive hepatoma cells, but not in AFP-negative hepatoma cells, normal liver cells, and non-hepatocytes, and the same results were obtained particularly in the primary cells. Thus, it was confirmed that these gene expression regulatory sequences have a specific expression activity of AFP-positive hepatoma cells. If rAFP is shortened to 0.67 kb, it still maintains excellent cell specificity and high activity. These gene regulatory sequences are expected to be used for specific gene therapy of primary hepatocellular carcinoma