Lee Dong Hyeon, Nam Joon Yeul, Chang Young, Cho Hyeki, Kang Seong Hee, Cho Young Youn, Cho EunJu, Lee Jeong-Hoon, Yu Su Jong, Kim Yoon Jun, Yoon Jung-Hwan
a Department of Internal Medicine and Liver Research Institute , Seoul National University College of Medicine , Seoul , Korea.
b Department of Internal Medicine , Seoul Metropolitan Government-Seoul National University Boramae Medical Center , Seoul , Korea.
Cancer Biol Ther. 2017 Jan 2;18(1):67-75. doi: 10.1080/15384047.2016.1276132.
Long-term prognosis of hepatocellular carcinoma (HCC) remains poor owing to the lack of treatment options for advanced HCC. Cytokine-induced killer (CIK) cells are ex vivo expanded T lymphocytes expressing both NK- and T-cell markers. CIK cell therapy alone is insufficient for treating advanced HCC. Thus, this study aimed to determine whether treatment with CIK cells combined with valproic acid (VPA) could provide a synergistic effect to inhibit tumor growth in a mouse model of HCC.
Upregulation of natural killer group 2D (NKG2D) ligands (retinoic acid early inducible 1 [RAE-1], mouse; major histocompatibility complex class I polypeptide-related sequence A [MIC-A], human) were evaluated by FACS. VPA concentrations that did not reduce tumor volume were calculated to avoid VPA cytotoxicity in a C3H mouse model of HCC. CIK cells were generated from mouse splenocytes using interferon gamma, a CD3 monoclonal antibody, and interleukin 2. The potential synergistic effect of CIK cells combined with VPA was evaluated in the mouse model and tissue pathology was investigated.
After 40 h of incubation with VPA, RAE-1 and MIC-A expression were increased in 4 HCC cell lines compared with that in control (2.3-fold in MH-134, 2.4-fold in Huh-7, 3.7-fold in SNU-761, and 6.5-fold in SNU-475). The maximal in vivo VPA dosage that showed no significant cytotoxicity compared with control was 10 mg/kg/day. CIK cells were well generated from C3H mouse splenocytes. After 7 d of treatment with CIK cells plus VPA, a synergistic effect was observed on relative tumor volume in the mouse model of HCC. While the relative tumor volume in untreated control mice increased to 11.25, that in the combination treatment group increased to only 5.20 (P = 0.047).
The VPA-induced increase in NKG2D ligands expression significantly enhanced the effects of CIK cell therapy in a mouse model of HCC.
由于晚期肝细胞癌（HCC）缺乏有效的治疗方案，其长期预后仍然较差。细胞因子诱导的杀伤细胞（CIK）是体外扩增的同时表达NK细胞和T细胞标志物的T淋巴细胞。单纯CIK细胞治疗不足以治疗晚期HCC。因此，本研究旨在确定CIK细胞联合丙戊酸（VPA）治疗是否能在HCC小鼠模型中产生协同作用以抑制肿瘤生长。
通过流式细胞术评估自然杀伤细胞2D（NKG2D）配体（小鼠的视黄酸早期诱导蛋白1 [RAE-1]；人类的主要组织相容性复合体I类多肽相关序列A [MIC-A]）的上调情况。计算在C3H HCC小鼠模型中不降低肿瘤体积的VPA浓度，以避免VPA的细胞毒性。使用γ干扰素、CD3单克隆抗体和白细胞介素2从小鼠脾细胞中生成CIK细胞。在小鼠模型中评估CIK细胞联合VPA的潜在协同作用，并研究组织病理学。
与对照组相比，4种HCC细胞系与VPA孵育40小时后，RAE-1和MIC-A表达增加（MH-134中增加2.3倍，Huh-7中增加2.4倍，SNU-761中增加3.7倍，SNU-475中增加6.5倍）。与对照组相比无明显细胞毒性的最大体内VPA剂量为10 mg/kg/天。CIK细胞可从C3H小鼠脾细胞中良好生成。CIK细胞加VPA治疗7天后，在HCC小鼠模型中观察到对相对肿瘤体积的协同作用。未治疗的对照小鼠的相对肿瘤体积增加到11.25，而联合治疗组仅增加到5.20（P = 0.047）。
VPA诱导的NKG2D配体表达增加显著增强了CIK细胞疗法在HCC小鼠模型中的效果。
