[摘 要] 目的：探究肌动蛋白样蛋白6A（ACTL6A）通过调控铁死亡参与弥漫大B细胞淋巴瘤（DLBCL）细胞多柔比星（DOX）耐药的机制。方法：培养亲本DLBCL细胞SU-DHL-4与耐药细胞SU-DHL-4/DOX，qPCR和WB法检测ACTL6A表达变化；通过转染携带靶向ACTL6A干扰序列（sh-ACTL6A）及其阴性对照（sh-NC）的质粒，构建敲减ACTL6A的SU-DHL-4/DOX，qPCR和WB法检测转染后细胞中ACTL6A、铁死亡相关蛋白谷胱甘肽过氧化酶4（GPX4）、溶质载体家族7成员11（SLC7A11）、长链酰基辅酶A合成酶4（ACSL4）的表达水平，染色质免疫沉淀（ChIP）、双萤光素酶报告基因实验验证ACTL6A与GPX4间的靶向结合与调控作用。将SU-DHL-4/DOX细胞分为对照组、sh-NC组、sh-ACTL6A组、sh-NC + oe-GPX4组和sh-ACTL6A + oe-GPX4组，用转染试剂将相应质粒转染至细胞中，qPCR和WB法检测各组细胞中ACTL6A和GPX4表达水平，CCK-8法检测不同浓度DOX处理后各组细胞存活率，FerroOrange探针检测各组细胞中亚铁离子（Fe2+）水平，Liperfluo探针检测各组细胞中脂质过氧化物水平，DCFH-DA探针检测各组细胞中活性氧（ROS）水平，比色法检测各组细胞中谷胱甘肽（GSH）和丙二醛（MDA）含量。结果： 与SU-DHL-4细胞相比，SU-DHL-4/DOX细胞中ACTL6A mRNA和蛋白均呈高表达（均P < 0.05）；ACTL6A与GPX4间存在靶向结合关系；敲减ACTL6A后SU-DHL-4/DOX细胞中ACTL6A和GPX4 mRNA及其蛋白表达水平均明显下降（均P < 0.05），表明ACTL6A可调控GPX4的表达；敲减ACTL6A可抑制SU-DHL-4/DOX细胞的存活率，促进细胞内Fe2+、脂质过氧化物、ROS、MDA的生成，抑制GSH生成（均P < 0.05）；而在敲减ACTL6A的同时过表达GPX4可上调SU-DHL-4/DOX细胞中GPX4的mRNA及其蛋白表达水平（均P < 0.05），并提高细胞存活率，抑制细胞内Fe2+、脂质过氧化物、ROS、MDA的生成，并增加GSH生成（均P < 0.05）。结论：ACTL6A在DOX耐药DLBCL细胞中高表达，通过调控GPX4表达抑制铁死亡，促进DLBCL细胞耐药。

ObjectiveTo investigate the effect of the expression level of diacylglycerol kinase gamma (DGKγ) in paracancerous tissue on the postoperative prognosis of patients with hepatocellular carcinoma (HCC) and its clinical value. MethodsRelated clinical data were collected from 78 HCC patients who were admitted and underwent surgical resection from December 2008 to August 2012 in the Affiliated Cancer Hospital of Zhengzhou University. Quantitative real-time PCR was used to measure the mRNA expression level of DGKγ in paracancerous tissue, and then the 78 patients were divided into low expression group (DGKγ ＜0.086 2, LEP group) and high expression group (DGKγ ≥0.086 2, HEP group). Basic data and clinical features were compared between the two groups. The t-test and the Mann-Whitney U test were used for comparison of continuous data, and the chi-square test and the corrected chi-square test were used for comparison of categorical data. Univariate and multivariate Cox regression analyses were used to investigate independent influencing factors for survival and prognosis, and the Kaplan-Meier method was used to analyze the overall survival trends of all patients and the LEP and HEP groups in each subgroup of Barcelona Clinic Liver Cancer (BCLC) stages. ResultsThe multivariate Cox regression analysis showed that the expression level of DGKγ (HR=1.913，95%CI： 1.111-3.296，P=0.019), HBsAg (HR=2.645，95%CI：1.264-5.537，P=0.010), Alb (HR=0.952，95%CI：0.916-0.990，P=0.013), BCLC stage (HR=1.702，95%CI：1267-2.286，P＜0001) and tumor size (HR=1.083，95%CI：1.019-1.152，P=0011) were independent influencing factors for long-term survival of HCC patients； the LEP group had a significantly longer median survival time than the HEP group (45.0 months vs 22.9 months, P=0002 5). The stratified analysis showed that for BCLC stage A HCC, the LEP group had significantly better long-term survival than the HEP group (P=0.034 5); for BCLC stage B/C HCC, the LEP group had a longer median survival time than the HEP group (16.5 months vs 10.8 months), but there was no significant difference in short- and long-term survival between the two groups (P＞0.05). ConclusionThe expression level of DGKγ in paracancerous tissue may be a new index for predicting and evaluating the long-term survival risk of HCC patients after surgery and has certain value in clinical application.