长链非编码RNA肺腺癌转移相关转录本1表达影响裸鼠骨肉瘤增殖的病理改变

Pathological changes of osteosarcoma proliferation caused by long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 in nude mice

目的探讨长链非编码RNA肺腺癌转移相关转录本1(MALAT-1)表达对裸鼠皮下植入的骨肉瘤增殖和病理学形态的影响。方法使用慢病毒感染构建MALAT-1稳定低表达的骨肉瘤U2OS细胞系,qPCR法验证MALAT-1表达的改变。将12只4~6周龄的雄性裸鼠随机平均分为实验组和对照组,实验组皮下植入MALAT-1稳定低表达的骨肉瘤U2OS细胞,对照组皮下植入空载慢病毒处理的骨肉瘤U2OS细胞。分别在植入后第3、6、9、12、15、18、21天测定并记录两组裸鼠皮下骨肉瘤的体积。植瘤后第21天处死裸鼠,完整取出骨肉瘤称重,通过H-E染色观察骨肉瘤病理学形态,免疫组织化学染色观察增殖细胞核抗原(PCNA)和血管内皮生长因子(VEGF)的表达。结果与对照组相比,实验组的肿瘤生长更慢,植瘤21 d后的体积、质量均小于对照组(P均<0.01)。H-E染色结果显示,实验组肿瘤基质成分增多,肿瘤细胞密集程度降低。免疫组织化学染色结果显示,实验组PCNA阳性染色积分光密度(IOD)中位数为8531.03、阳性细胞占比为29.3%(1758/6000),对照组IOD中位数为27548.23、阳性细胞占比为56.5%(3392/6000),实验组PCNA表达程度较对照组下降,差异均有统计学意义(P均<0.05);实验组VEGF阳性染色IOD为18179.490±18299.433、阳性细胞占比为51.0%(3063/6000),对照组IOD为15850.632±9341.063、阳性细胞占比为50.0%(3001/6000),两组VEGF表达程度差异无统计学意义(P均>0.05)。结论抑制骨肉瘤中长链非编码RNA MALAT-1的表达可以延缓肿瘤的生长,降低肿瘤的侵袭性,促进实体瘤中肿瘤细胞的坏死。

Objective To explore the effect of long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1(MALAT-1)expression on the proliferation and pathology of osteosarcoma implanted subcutaneously in nude mice.Methods The osteosarcoma U2OS cell line with stable low expression of MALAT-1 was constructed by lentivirus infection,and the expression of MALAT-1 was verified by quantitative real-time polymerase chain reaction(qPCR).Twelve male nude mice aged 4-6 weeks were randomly divided into experimental group and control group.Osteosarcoma U2OS cells with stable low expression of MALAT-1 were implanted subcutaneously in the experimental group,while osteosarcoma U2OS cells infected by empty lentivirus were implanted subcutaneously in the control group.The volumes of subcutaneous osteosarcoma were measured and recorded on the 3rd,6th,9th,12th,15th,18thand 21stdays after implantation.On the 21stday after tumor transplantation,the nude mice were sacrificed.The osteosarcoma was taken out completely and weighed.The microscopic morphology of the osteosarcoma tissue was observed with hematoxylin-eosin(H-E)staining,and the expression levels of proliferacting cell nuclear antigen(PCNA)and vascular endothelial growth factor(VEGF)were detected by immunohistochemistry.Results Compared with the control group,the tumors in the experimental group grew slower and had smaller volume and weight on the 21stday after implantation(both P<0.01).H-E staining showed that there was increased matrix composition and decreased cell density in the tumors of the experimental group.Immunohistochemistry showed that PCNA expression was decreased in the tumors of the experimental group(P<0.05).In the experimental group,the median integral optical density(IOD)of PCNA positive staining was 8531.03,and the expression rate of positive cells was29.3%(1758/6000).In the control group,the median IOD was 27548.23,and the positive cell expression rate was 56.5%(3392/6000).There was no significant difference in the expression of VEGF between the experimental group and the control group(P>0.05).In the experimental group,the IOD of VEGF positive staining was 18179.490±18299.433,and the expression rate of positive cells was 51.0%(3063/6000).In the control group,the IOD was 15850.632±9341.063,and the positive cell expression rate was 50.0%(3001/6000).Conclusion Inhibiting the expression of MALAT-1 in osteosarcoma can slow down tumor growth,reduce tumor invasiveness,and promote tumor cell necrosis in solid tumors.