原癌基因c-myc、c-H-ras、c-sis在小鼠卵巢和睾丸中的转录表达研究

以地高辛标记ｃ－ｍｙｃ、ｃ－Ｈ－ｒａｓ、ｃ－ｓｉｓ基因作探针，利用组织切片原位杂交的方法，检测了昆明种小鼠５周龄、１０周龄和孕期卵巢，以及１天龄、５周龄和１０周龄睾丸，初步研究了这３种原癌基因在生殖腺中的转录表达及其可能的功能作用。结果显示：（１）ｃ－ｍｙｃ基因在孕鼠卵巢的个别卵泡的卵泡细胞中有强转录信号，但在３组卵巢的卵母细胞中及３组睾丸切片中均未见杂交信号。（２）ｃ－Ｈ－ｒａｓ基因在孕鼠卵巢黄体中有较强转录表达，但在３组卵巢的卵母细胞中及３组睾丸切片中均无杂交信号，（３）ｃ－ｓｉｓ基因在１０周龄睾丸曲细精管的精原细胞层和精母细胞有强转录表达，而在１天龄、５周龄睾丸及３组卵巢切片中均无杂交信号。上述结果表明：ｃ－ｍｙｃ基因可能与精子发生和卵子的发育关系不大，但可能与卵泡的退化有关；ｃ－Ｈ－ｒａｓ基因可能与精子发生和卵子的发育关系也不大，但可能与妊娠黄体的形成有关；ｃ－ｓｉｓ基因可能与卵子的发育无关。

A COMPARISON OF THE PROTOONCOGENES BETWEEN THE HUMAN GASTRIC CANCEROUS AND NORMAL MUCOSAL TISSUES

The allelic distribution of EcoRI and BamHI fragments of ras family genes between the human primary gastric cancer tissues and the corresponding adjacent normal tissues did not show any differences. Three genotypes of BamHI restriction fragment length polymorphism of c-H-ras were revealed. No significant differences in the RFLPs were observed between normal individuals and gastric cancer patients. Four protooncogenes, c-H-ras, N-ras, c-myc and c-fos, were found to be transcriptionally active in the gastric cancer tissues in some cases examined. The comparison of the expression of these oncogenes between the malignant tissues and the corresponding normal tissues showed differential patterns. The expression of c-H-ras at cellular level was detected by in situ hybridization. The enhanced expression of c-H-ras in the gastric cancer cells was demonstrated, but the degree of the expression among the cancer cells was shown to be heterogeneous. In addition, the enhanced expression of c-H-ras was seen in the inflammatory cells.

反义c－Ha－rasDNA对人胃癌转化细胞致癌性的抑制

作者人工合成了一条１５聚反义ｃ－Ｈａ－ｒａｓＤＮＡ，此反义ＤＮＡ与ｃ－Ｈａ－ｒａｓ基因转录起始区域的序列互补。其可以在转录和翻译水平上阻断ｃ－Ｈａ－ｒａｓ基因表达，使胃癌转化细胞的一些恶性表型（包括生长速度、软琼脂中集落形成，裸鼠致瘤性和分化程度）发生逆转。在反义ＤＮＡ的５’－端共价连接一个补骨脂素基团后，其生物学活性显著增强，和靶基因序列不完全配对的对照寡聚核苷酸链不具有上述肿瘤抑制效应。结果提示：反义ＤＮＡ及其衍生物是进行肿瘤基因治疗有效工具之一。