白细胞介素24对裸鼠人宫颈癌Hela细胞移植瘤抑制作用的探讨

The Inhibitory Effect of IL-24 on Tumor Growth of Human Nude Mice Model of Cervical Cancer

目的:探讨基因重组质粒pDC316-hIL-24对裸鼠人宫颈癌模型的肿瘤生长及凋亡的作用。方法:于5周龄裸鼠腋窝外侧皮下注射1×107个/mL Hela细胞悬液100μL,将15只构建成功的人宫颈癌Hela细胞裸鼠模型随机分为3组,分别于瘤体内注射转染试剂Lipofectamine 2000与基因重组质粒pDC316-hIL-24(A组)、空质粒pDC316(B组)以及磷酸盐缓冲液(C组),比较干预后各组移植瘤的体积及抑瘤率。应用RT-PCR法测定移植瘤中hIL-24的表达,HE染色观察各组肿瘤组织形态学变化,免疫组化方法研究肿瘤细胞凋亡情况。结果:①IL-24基因成功转染入肿瘤细胞并在其中成功表达,至实验结束时,B组和C组移植瘤体积大于A组(F=63.395,P<0.05);A组的平均抑瘤率高于B组(t=130.920,P<0.01)。②病理学观察见A组宫颈癌细胞有局灶性坏死,细胞变大,胞质疏松,核深染,可见核固缩、核溶解、核碎裂,染色质成团状。③免疫组化结果显示,A组BCL-2蛋白表达低于其他2组(F=6.164,P<0.05),而其同源蛋白BAX表达高于其他2组(F=58.426,P<0.05)。结论:基因重组质粒pDC316-hIL-24对宫颈癌裸鼠模型肿瘤生长具有明显的抑制作用,其可能通过激活细胞凋亡通路而诱导肿瘤细胞凋亡。

Objective： To investigate the inhibition function of gene recombinant plasmid pDC316-hIL-24 on human cervical cancer nude mice model tumor growth. Methods： Cervical cancer Hela cells were injected in a 1 × 107 cell/L concentration into the central lateral subcutaneous of the left armpit of nude mice of 5 weeks age. Con- struction of nude mice model of human cervical cancer. The 15 nude mice were randomly divided into 3 groups, and recombinant plasmids （group A ） or empty plasmids （group B ） as well as PBS （group C ） were injected into transplanted tumor with Lipofectamine 2000 to interfere with the growth of transplanted tumor. Comparison of tumor volume and inhibitory rate after the intervention, determination of hIL-24 expression in transplanted tumor by RT-PCR, observation of morphological changes of tumor tissues in each group by HE staining and as well as immunohistochemistry was employed for investigating tumor cell apoptosis in each group. Results： （1） After wansfection IL-24 gene was successfully transfected into tumor cells and has been successfully expressed in tumor cells. To the end of the experiment, group C and group B tumor volume was significantly greater than group A （F =63.395, P 〈0.05 ）. The average inhibition rate of group A was significantly higher than group B （t = 130.920, P 〈0.01 ）. （2） Pathological observation shows in group A cervical cancer cells have focal necrosis and cells become large, and loose cytoplasm, nucleus deeply stained, pyknosis, nuclear dissolution, nuclear fragmentation, ehromatin lumps also can be found. （3） Immunohistochemistry showed that, compared with the other two groups, group A proto-oncogene BCL-2 expression was lower than the other two groups （F=6.164, P 〈0.05 ）, but its homologous protein BAX expression was higher than the other two groups （F=58.426, P 〈0.05 ）. Conclusion： Recombinant plasmid pDC316-hlL-24 has significant inhibition function on human cervical cancer nude mice model tumor growth. IL-24 may activate apoptosis or anti-apoptosis pathway to induce tumor cell nuclear condensation, fragmentation and apoptosis.