转染血小板因子4基因或其片段在动物体内抑制多发性骨髓瘤的生长

Suppression of Multiple Myeloma Tumor Growth In Vivo by Transfection of Platelet Factor 4 or 17-70 cDNA

本研究旨在观察血小板因子4cDNA全长或其17-70片段转染多发性骨髓瘤细胞株对其在动物体内生长的影响。构建含有人血小板因子4cDNA全长或17-70片段的慢病毒载体,转染、筛选并检测稳定表达转染基因蛋白的多发性骨髓瘤U266细胞株。用稳定表达转染基因蛋白的U266细胞建立多发性骨髓瘤联合免疫缺陷小鼠动物模型。每2周检测小鼠血清中人轻链蛋白的含量,每4周测量小鼠血清中人VEGF及PF4蛋白含量。并检测肿瘤的体积和肿瘤内血管密度以及小鼠的生存期。结果表明:成功筛选出稳定表达血小板因子4蛋白和其17-70肽段的多发性骨髓瘤细胞株。筛选后各组多发性骨髓瘤细胞上清液内VEGF含量之间有统计学差异(p<0.01)。应用转染后多发性骨髓瘤细胞建立小鼠多发性骨髓瘤模型发现,和转染空载体组相比较,转染血小板因子4基因组小鼠血清中人VEGF及人轻链蛋白含量降低,在转染17-70片段组的降低更加明显(p<0.05)。各组小鼠肿瘤平均体积及肿瘤组织内微血管密度之间有统计学差异(p<0.05)。转染空载体组小鼠与其它两组小鼠之间生存期有统计学差异(p<0.05)。转染血小板因子4小鼠与转染血小板因子4片段组小鼠之间生存期无统计学差异(p>0.05)。结论:转染血小板因子4cDNA全长或其17-70片段的多发性骨髓瘤细胞在小鼠体内生长受到抑制,小鼠生存期延长。

This study was purposed to investigate the effects of viral vector-mediated gene transfer of platelet factor 4（PF4） or 17-70 cDNA on cell growth of multiple myeloma（MM） in vivo.Full length and p17-70 cDNA of PF4 were cloned into virapowerTM system to transfect packing cell line 293 and produce lentiviral vectors.3 multiple myeloma cell lines were transferred platelet factor 4 or 17-70 cDNA by lentiviral vectors.SCID-rab mice models of multiple myeloma were established by injecting U266 multiple myeloma cells selected.The human light chain proteins and VEGF in serums of mice were detected every 2 weeks.The volumes and vascular density of tumors as well as survival time of mice were observed.The results showed that the MM cells expressing foreign genes were identified and screened.There were significant difference of VEGF levels in the supernatants of MM cells between each groups（p0.01）.The SCID-rab models of U266 cells were established successfully.There were significant differences in light chain protein and VEGF in serums among three groups（p0.01）.The light chain protein and VEGF in mice serums of 17-70 cDNA groups were less than that of PF4 group（p0.01）.The light chain protein and VEGF in mice serums of PF4 group were less than that of control group（p0.01）.There were significant differences in the tumor volumes and the vascular density of tumor among 3 groups（p0.05）.The results also showed that there were significant differences of overall survival in 3 different groups of SCID-rab MM models.The overall survival in control group was shortest as compared with other groups（p0.05）.It is concluded that the cell growth of multiple myeloma is suppressed in vivo by transfection of platelet factor 4 or 17-70 cDNA and the overall survivl of transfected mice will be prolonged.