SCL基因反义寡核苷酸对K562和CEM细胞系的作用

干细胞白血病(SCL)基因是新发现的与白血病发生有关的癌基因。为进一步探讨SCL反义寡核苷酸对白血病细胞的作用，本研究应用SCL基因的反义硫代磷酸寡脱氧核苷酸(AS—PS—ODN)分别与K562和CEM白血病细胞系作用，观察细胞生长、分化、凋亡和SCL　mRNA变化。结果显示：(1)AS—PS—ODN对K562和CEM细胞的生长有不同程度的抑制作用，并呈量效和时效关系；(2)AS—PS—ODN作用后K562细胞联苯胺染色阳性率明显增加；(3)AS—PS—ODN作用后K562细胞发生凋亡现象，但未观察到CEM细胞凋亡；(4)AS—PS—ODN作用后K562细胞和CEM细胞SCL　mRNA表达水平减低，同时CEM细胞SIL－SCL　mRNA表达水平也减低。结论：AS—PS—ODN能特异性抑制K562和CEM细胞的增殖，减低SCL　mRNA和SIL—SCL　mRNA表达水平，同时促进红系分化，诱导K562细胞过早凋亡。

Effects of SCL Antisense Oligonucleotides on K562 and CEM Cell Lines

The stem cell leukemia(SCL) gene is a new oncogene related with leukemogenesis. To explore the effects of antisense oligonucleotides of SCL on leukemic cells, SCL antisense phosphorothioate oligodeoxynucleotides(AS PS ODN) were used to treat K562 and CEM leukemic cell lines to observe the effects on proliferation, differentiation, apoptosis and SCL mRNA expression in the cells. The results showed that incubation of K562 or CEM cells with AS PS ODN at different concentrations led to inhibition of cell proliferation, and the inhibitory effects varied with the incubation time. The positive rate of benzidine staining in K562 cells increased significantly after the inhibition with AS PS ODN, compared with S PS ODN treatment. The charateristics of apoptosis were observed in K562 cells treated with AS PS ODN, but not in CEM cells. Expression of SCL mRNA in K562 and CEM cells and SIL SCL mRNA in CEM cells decreased after incubation of AS PS ODN. It is concluded that SCL AS PS ODN inhibits specifically the proliferation of K562 and CEM cells, also decreases the level of SCL and SIL SCL mRNA expression. AS PS ODN enhances erythroid differentiation and induces premature apoptosis in K562 cells.