隔蛋白7逆转裸鼠移植胶质瘤的恶性表型

目的探讨隔蛋白（SEPT）7对胶质瘤恶性表型的影响。方法建立SEPT7表达缺失的人胶质瘤TJ905细胞的裸鼠皮下移植瘤模型，将荷瘤鼠分为治疗组（SEVIT／pcDNA3）、空载体组（pcDNA3）和对照组（PBS），观察各组肿瘤的大小及生长速度；采用免疫组化法检测各组肿瘤组织标本中SEPT7、增殖细胞核抗原（PCNA）、胶质纤维酸性蛋白（GFAP）、侵袭相关因子基质金属蛋白酶（MMP）-2、MMP-9]、细胞周期因子（CDK2、CDK4、cyclinD1、cyclinE、p21、p16）以及凋亡相关因子（bcl-2、caspase-3）的表达；原位末端标记（TUNEL）法检测肿瘤细胞的凋亡。结果治疗组肿瘤的生长速度明显减慢，6d后肿瘤体积明显小于对照组和空载体组（P〈0．05）；治疗组肿瘤标本中SEV17、p21、p16和caspase-3的表达上调，PCNA、MMP-2、MMP-9、CDK2、CDK4、cyclinD1、cyclinE和bcl-2的表达下降，且GFAP呈阳性表达；TUNEL法检测治疗组肿瘤细胞凋亡增加。结论SEPT7可抑制肿瘤生长、增殖和侵袭，并诱导肿瘤细胞凋亡，对胶质瘤的恶性表型具有逆转作用。

Effect of SEPT7 on the malignant phenotype of transplanted glioma in nude mice

Objective To study the effect of SEPT7 on glioma cell growth, cell cycle progression, invasion and apoptosis in vivo. Methods Nude mice with subcutaneously transplanted human glioma TJ905, in which SEPT7 is absent, were divided into three groups: SEPT7 treatment group, empty vector treatment group, and control group (PBS). The expression of SEPTT, PCNA, GFAP, proteins involved in the regulation of G1/S phase progression (cylcin D1, cylcin E, CDK2, CDK4, p21, p16), as well invasion-related factors (MMP2, MMPg) and apoptosis-related factors ( bcl-2, caspase-3) were determined by immunohistochemistry in the glioma samples taken from the mice in the three groups. TUNEL method was used to detect the apoptotic index of tumors. Results During the 4 weeks-observation period, the growth rate of gliomas in the nude mice in SEPT7 group was significantly slowed down and the tumor volume was much smaller than those in control and empty vector groups. In the glioma treated with SEPTT, the expressions of SEPTT, p21., p16 and caspase-3 were significantly upregulated, the expressions of PCNA, MMP-2, MMP-9, cyclin D1, cyclin E, CDK2, CDK4 and bcl-2 were reduced, and GFAP was positive. Increase of apoptotic cells was observed by TUNEL. Conclusion SEPT7 can reverse the malignant phenotype of glioma cells by inhibition of cell growth and invasion, and induction of apoptosis, and SEPT7 is supposed preliminary to be a tumor suppressor gene.