Zou Chun-Hua, Tian Ling, Wei Yu-Quan, Zhao Xia, Kan Bing, Yang Jin-Liang, Mao Yong-Qiu, Wen Yan-Jun, Li Jiong, Deng Hong-Xin
Key Laboratory of Biotherapy of Human Diseases, Ministry of Education,and Biotherapy and Research Center of Cancer,West China Hospital, Chengdu,Sichuan, 610041, P.R.China.
Ai Zheng. 2004 Jan;23(1):1-7.
BACKGROUND & OBJECTIVE: Chemokines are small molecule proteins that are the main mediators of cell migration. Studies indicated that chemokines could induce antitumor immune response strongly and steadily. At present, there was not antitumor therapy about chemokine BLC combined with chemotherapy. This study was designed to explore the anti-tumor effects and mechanisms of BLC-modified tumor cell vaccine combined with cisplatin.
Firstly, we transfected pcDNA-BLC into murine tumor cell lines and established stable transfected tumor cell lines (Colon26 and LL/2) to express BLC. Null plasmid pcDNA3.1 (+) was also transfected into Colon 26 or LL/2 cells stably for comparison. We established mouse model with pcDNA-BLC stable transfected tumor cells (Tc), control mouse model with pcDNA3.1(+) stable transfected tumor cells (Pc), and mouse model with parental tumor cells (Nc). Then the 60 mice were inoculated subcutaneously (s.c.) in the right flanks with a total of 5x10(5) viable tumor cells (Tc to 20 mice, Pc to 20 mice, and Nc to 20 mice, respectively; 6-8 week BALB/c female mouse in colon 26 mouse model or 6-8 week C57BL/6 female mouse in LL/2 mouse model). The groups (Tc, Pc, and Nc) were randomly subdivided into Group A and Group B with 10 mice for each, resulting in Tc-A/Tc-B, Pc-A/Pc-B, and Nc-A/Nc-B, respectively. Group A (including Tc-A, Pc-A, and Nc-A) as chemotherapy group was injected (i.p.) with 0.1 ml cisplatin at the concentration of 2 mg/kg once a week for two weeks; Group B (including Tc-B, Pc-B, and Nc-B) as control with 0.1 normal saline. We further observed anti-tumor activity including the tumor growth, mice survival rate, side effects as well as tumor morphological analysis. Apoptotic cells were also determined in tumor tissues.
The combination therapy group Tc-A showed significant anticancer activities. The tumor growth was inhibited efficiently with 3/10 mice showing complete regression in LL/2 mouse model and 1/10 mice showing complete regression in Colon 26 mouse model. The combination therapy group Tc-A showed that the survival rate of mice was 100% in the two mouse models, compared with 68% in group Tc-B in C57BL/6 mouse model and 65% in group Tc-B in Colon 26 mouse model and those in other groups. In addition, the combination therapy group Tc-A induced tumor cell apoptosis significantly.
The therapy of BLC-modified tumor cell vaccine combined with cisplatin had significant synergistic effect against tumor. It might develop a new approach for specific immunotherapy of tumors.
趋化因子是细胞迁移的主要介导因子，属于小分子蛋白。研究表明，趋化因子能强烈且稳定地诱导抗肿瘤免疫反应。目前，尚无关于趋化因子BLC联合化疗的抗肿瘤治疗方法。本研究旨在探讨BLC修饰的肿瘤细胞疫苗联合顺铂的抗肿瘤作用及机制。
首先，将pcDNA-BLC转染至小鼠肿瘤细胞系，建立稳定转染的肿瘤细胞系（Colon26和LL/2）以表达BLC。空质粒pcDNA3.1(+)也稳定转染至Colon 26或LL/2细胞用于对照。我们用pcDNA-BLC稳定转染的肿瘤细胞建立小鼠模型（Tc），用pcDNA3.1(+)稳定转染的肿瘤细胞建立对照小鼠模型（Pc），并用亲本肿瘤细胞建立小鼠模型（Nc）。然后，将60只小鼠右腹侧皮下接种总共5×10(5)个活肿瘤细胞（分别接种20只Tc小鼠、20只Pc小鼠和20只Nc小鼠；在Colon 26小鼠模型中为6-8周龄的BALB/c雌性小鼠，在LL/2小鼠模型中为6-8周龄的C57BL/6雌性小鼠）。将各组（Tc、Pc和Nc）随机分为A组和B组，每组10只小鼠，分别为Tc-A/Tc-B、Pc-A/Pc-B和Nc-A/Nc-B。A组（包括Tc-A、Pc-A和Nc-A）作为化疗组，每周腹腔注射（i.p.）一次0.1 ml浓度为2 mg/kg的顺铂，共两周；B组（包括Tc-B、Pc-B和Nc-B）作为对照组，注射0.1生理盐水。我们进一步观察了抗肿瘤活性，包括肿瘤生长、小鼠存活率、副作用以及肿瘤形态分析。还测定了肿瘤组织中的凋亡细胞。
联合治疗组Tc-A显示出显著的抗癌活性。在LL/2小鼠模型中，肿瘤生长得到有效抑制，3/10的小鼠完全缓解；在Colon 26小鼠模型中，1/10的小鼠完全缓解。联合治疗组Tc-A显示，在两种小鼠模型中，小鼠存活率均为100%，而在C57BL/6小鼠模型的Tc-B组中为68%，在Colon 26小鼠模型的Tc-B组中为65%，其他组也如此。此外，联合治疗组Tc-A显著诱导肿瘤细胞凋亡。
BLC修饰的肿瘤细胞疫苗联合顺铂治疗对肿瘤具有显著的协同作用。这可能为肿瘤的特异性免疫治疗开辟一条新途径。
