目的 探讨可否将果蝇多底物脱氧核苷酸激酶（Dm-dNK）表达于乳腺癌细胞，以及其对肿瘤细胞的杀伤效果。

方法

构建表达Dm-dNK复制缺陷的逆转录病毒载体；重组病毒感染乳腺癌细胞系MCF7（ER+）及MDA-MB-231（ER-），测定感染细胞酶的活性及对于核苷酸类似物araT 及araC的细胞毒性。

结果

Dm-dNK可以在乳腺肿瘤细胞中表达并具有酶的活性（Western印迹显示细胞内的Dm-dNK蛋白表达）；同时，感染的肿瘤细胞对araT及araC的敏感性增加。

结论

Dm-dNK可以定位表达于乳腺肿瘤细胞核并保持酶的活性，Dm-dNK可能成为乳腺肿瘤分子化疗的新方法。

Objective

To evaluate the effects of nucleoside analogphosphorylation by Dm-dNK（Drosophila melanogaster deoxyribonucleosidekinase）， and the killing effect as a novel suicide geneon in breast cancer cell lines.

Methods

A replication-deficientretroviral'vector that expresses Dm-dNK was created， and the human breast cancer cells MCF7 （ER + ） and MDA-MB-231 （ER- ） were transduced with the recombinant retrovirus.The enzymatic activity and the sensitivity of the untransfected cells and the cells infected with either GFP （green fluorescent protein） vector alone or the pLE-Dm-dNK-GFP to pyrimidine nucleoside analogs araT（1-β-Darabinofuranosylthymine） and araC （1-β-D-arabinofuranosylcytosine） were determined.

Results

It was showed that the Dm-dNK was enzymatically active and that the over-expression of the enzyme in the tested cell lines resulted in an increased sensitivity to the cytosine nucleoside analogs araT and araC.

Conclusions

Dm-dNK can be locally overexpressed in the nuclei of breast cancer cells and it retains enzymatic activity.It may contribute to the development of novel breast cancer treatment strategies.