CAJ | 학술논문

目的评价IFN-γ和内皮抑素(endostatin)双基因-放射治疗在小鼠转移性乳腺癌中的抑瘤效应,并探讨其可能的作用机制.方法用脂质体包裹pEgr-IFN-γ和pEgr-endostatin质粒转染小鼠乳腺腺癌4T1细胞,并用X射线照射,吸收剂量为2～20 Gy.用ELISA检测细胞培养液上清中1FN-γ和内皮抑素的浓度.小鼠下肢注4T1肿瘤细胞1×105个,荷瘤小鼠随机分组为对照组、空质粒组,基因治疗组、放射治疗组及基因-放射治疗组,观察小鼠肿瘤生长及肺转移情况,计算肿瘤生长率、肿瘤/体重比及荷瘤小鼠生存率,并用流式细胞仪检测脾脏CTL和NK细胞的细胞毒活性,用免疫组织化学法检测肿瘤内部的微血管密度.结果辐射显著增强了4T1细胞分泌IFN-γ和内皮抑素的浓度.小鼠接受基因-放射治疗与单独接受基因治疗或者接受放射治疗相比,肿瘤生长率明显降低,同时生存率明显提高(t=8.724,P＜0.05).双基因联合放射治疗组小鼠脾中CTL和NK细胞的细胞毒活性及腹腔巨噬细胞的TNF-α水平较对照组明显升高(t=2.120、22.140和5.289,P＜0.05),微血管密度明显降低(t=13.294,P＜0.05).结论 IFN-γ和内皮抑素的基因-放射治疗增强了小鼠转移性乳腺癌的抑瘤效应,其机制可能与IFN-γ激活CTL和NK细胞活性及内皮抑素引起肿瘤血管生成抑制有关.
목적 평개IFN-γ화내피억소(endostatin)쌍기인-방사치료재소서전이성유선암중적억류효응,병탐토기가능적작용궤제.방법 용지질체포과pEgr-IFN-γ화pEgr-endostatin질립전염소서유선선암4T1세포,병용X사선조사,흡수제량위2～20 Gy.용ELISA검측세포배양액상청중1FN-γ화내피억소적농도.소서하지주4T1종류세포1×105개,하류소서수궤분조위대조조、공질립조,기인치료조、방사치료조급기인-방사치료조,관찰소서종류생장급폐전이정황,계산종류생장솔、종류/체중비급하류소서생존솔,병용류식세포의검측비장CTL화NK세포적세포독활성,용면역조직화학법검측종류내부적미혈관밀도.결과 복사현저증강료4T1세포분비IFN-γ화내피억소적농도.소서접수기인-방사치료여단독접수기인치료혹자접수방사치료상비,종류생장솔명현강저,동시생존솔명현제고(t=8.724,P＜0.05).쌍기인연합방사치료조소서비중CTL화NK세포적세포독활성급복강거서세포적TNF-α수평교대조조명현승고(t=2.120、22.140화5.289,P＜0.05),미혈관밀도명현강저(t=13.294,P＜0.05).결론 IFN-γ화내피억소적기인-방사치료증강료소서전이성유선암적억류효응,기궤제가능여IFN-γ격활CTL화NK세포활성급내피억소인기종류혈관생성억제유관.
Objective To evaluate the antitumor effects of interferon (IFN)γ-endostatin based gene radiotherapy in a metastatic breast tumor model of mice, and to elucidate the possible mechanisms involved. Methods Murine mammary adenocarcinoma 4T1 cells transfected with pEgr-IFN-γ and pEgrendostatin plasmids were irradiated with 2-20 Gy of X-rays. IFN-γ and endostatin levels in the culture supernatants were measured. Female BALB/c mice were inoculated with 1 × 105 of 4T1 cells by mammary fat pad injection, and divided randomly into control, empty vector, gene therapy (pEgr-IFN-γ and pEgrendostatin), radiotherapy, and combined gene-radiotherapy groups. Tumor/body weight ratio, lung metastases, and survival of the tumor-bearing mice were observed. Splenic cytotoxic T-lymphocyte (CTL)and natural killer (NK) cell activity and intratumor microvessel density were also assessed. Results Irradiation significantly enhanced the section of IFN-γ and endostatin from the transfected 4T1 cells.Compared with gene therapy or radiotherapy alone, combined gene-radiotherapy resulted in the maximal attenuation in tumor growth rate, lung metastases and increased survival. The activities of CTL and NK cells were significantly enhanced and intratumor microvessel density reduced ( t = 2. 120-22.140, P ＜ 0.05 ).Conclusions IFN-γ-endostatin-based gene-radiotherapy could provide a potential antitumor effect in a murine metastatic breast tumor model, which may be related to IFN-γ-stimulated CTL and NK cell activation, and endostatin-induced antiangiogenic activity. Gene-radiotherapy could serve as a neoadjuvant therapy for the locally advanced breast cancer.