Colorectal cancer(CRC)stands among the top prevalent cancers worldwide and holds a prominent position as a major contributor to cancer-related mortality globally.Absent in melanoma 2(AIM2),a constituent of the interfe...Colorectal cancer(CRC)stands among the top prevalent cancers worldwide and holds a prominent position as a major contributor to cancer-related mortality globally.Absent in melanoma 2(AIM2),a constituent of the interferoninducible hematopoietic interferon-inducible nuclear antigens with 200 amino acid repeats protein family,contributes to both cancer progression and inflammasome activation.Despite this understanding,the precise biological functions and molecular mechanisms governed by AIM2 in CRC remain elusive.Consequently,this study endeavors to assess AIM2’s expression levels,explore its potential antitumor effects,elucidate associated cancer-related processes,and decipher the underlying signaling pathways in CRC.Our findings showed a reduced AIM2 expression in most CRC cell lines.Elevation of AIM2 levels suppressed CRC cell proliferation and migration,altered cell cycle by inhibiting G1/S transition,and induced cell apoptosis.Further research uncovered the participation of P38 mitogen-activated protein kinase(P38MAPK)in AIM2-mediated modulation of CRC cell apoptosis and proliferation.Altogether,our achievements distinctly underscored AIM2’s antitumor role in CRC.AIM2 overexpression inhibited proliferation and migration and induced apoptosis of CRC cells via activating P38MAPK signaling pathway,indicating AIM2 as a prospective and novel therapeutic target for CRC.展开更多
目的探讨果蝇双翅边缘缺刻同源基因(Notch)信号通路在慢性阻塞性肺疾病(COPD)辅助性T细胞1(Helper T cells 1,Th1)和辅助性T细胞2(Helper T cells 2,Th2)失衡中的作用及芪蛭皱肺颗粒的干预机制。方法70只Wistar大鼠随机挑选10只作为空...目的探讨果蝇双翅边缘缺刻同源基因(Notch)信号通路在慢性阻塞性肺疾病(COPD)辅助性T细胞1(Helper T cells 1,Th1)和辅助性T细胞2(Helper T cells 2,Th2)失衡中的作用及芪蛭皱肺颗粒的干预机制。方法70只Wistar大鼠随机挑选10只作为空白对照组,其余大鼠均采用香烟烟雾(CS)联合气管滴注脂多糖(Lipopolysaccharide,LPS)法建立COPD模型,空白对照组及造模组各随机挑选3只大鼠验证造模是否成功。造模结束进行灌胃给药干预,造模组大鼠随机分为模型对照组、阳性对照组(67.5μg·kg^(-1))及芪蛭皱肺颗粒高中低剂量组(3.24、1.62、0.81 g·kg^(-1)),分别给予生理盐水、醋酸地塞米松混悬液、芪蛭皱肺高、中、低剂量混悬液进行灌胃干预,空白对照组同模型对照组,灌胃等体积生理盐水。经28天造模及28天治疗后,采用动物肺功能测试系统检测吸气峰流速(Peak Inspiratory Flow,PIF)和呼气峰流速(Peak Expiratory Flow,PEF),处死大鼠提取肺脏、脾脏、血清及支气管肺泡灌洗液(BALF),苏木素-伊红(HE)染色评价肺组织病理变化,酶联免疫吸附实验法(ELISA)测定血清及BALF中肿瘤坏死因子-α(TNF-α)含量,流式细胞仪检测脾脏Th1/Th2细胞水平,免疫组织化学法(Immunohistochemistry,IHC)及蛋白免疫印迹法(Western blot)检测肺组织Notch1、Hes家族发状分裂相关增强子1(Hes1)、Hey家族发状分裂相关增强子1(Hey1)蛋白水平,实时荧光定量聚合酶链式反应(Real-time PCR,RT-PCR)检测肺组织Notch1、Hes1、Hey1基因表达水平。结果与空白对照组比较,模型对照组大鼠肺功能显著降低(P<0.05),肺组织出现炎性细胞浸润、支气管结构破坏等病变,血清及BALF中TNF-α含量显著升高(P<0.05),脾Th1细胞百分比显著降低(P<0.05),Th2细胞百分比显著升高(P<0.05),肺组织Notch1、Hes1、Hey1蛋白及mRNA表达显著升高(P<0.05),差异均具有统计学意义;与模型对照组比较,各给药组大鼠肺功能显著升高(P<0.05),肺组织病理损伤均有所减轻,血清及BALF中TNF-α含量显著降低(P<0.05),脾Th1细胞百分比显著升高(P<0.05),Th2细胞百分比显著降低(P<0.05),肺组织Notch1、Hes1、Hey1蛋白及mRNA表达显著降低(P<0.05),差异均具有统计学意义。结论芪蛭皱肺颗粒通过抑制Notch信号通路调节Th1/Th2平衡,从而改善COPD大鼠肺功能及病理损伤,影响其免疫功能。展开更多
In traumatic brain injury, absent in melanoma 2(AIM2) has been demonstrated to be involved in pyroptotic neuronal cell death. Although the pathophysiological mechanism of spinal cord injury is similar to that of brain...In traumatic brain injury, absent in melanoma 2(AIM2) has been demonstrated to be involved in pyroptotic neuronal cell death. Although the pathophysiological mechanism of spinal cord injury is similar to that of brain injury, the expression and cellular localization of AIM2 after spinal cord injury is still not very clear. In the present study, we used a rat model of T9 spinal cord contusive injury, produced using the weight drop method. The rats were randomly divided into 1-hour, 6-hour, 1-day, 3-day and 6-day(post-injury time points) groups. Sham-operated rats only received laminectomy at T9 without contusive injury. Western blot assay revealed that the expression levels of AIM2 were not significantly different among the 1-hour, 6-hour and 1-day groups. The expression levels of AIM2 were markedly higher in the 1-hour, 6-hour and 1-day groups compared with the sham, 3-day and 7-day groups. Double immunofluorescence staining demonstrated that AIM2 was expressed by NeuN+(neurons), GFAP+(astrocytes), CNPase+(oligodendrocytes) and CD11 b+(microglia) cells in the sham-operated spinal cord. In rats with spinal cord injury, AIM2 was also found in CD45+(leukocytes) and CD68+(activated microglia/macrophages) cells in the spinal cord at all time points. These findings indicate that AIM2 is mainly expressed in neurons, astrocytes, microglia and oligodendrocytes in the normal spinal cord, and that after spinal cord injury, its expression increases because of the infiltration of leukocytes and the activation of astrocytes and microglia/macrophages.展开更多
目的探讨血清黑色素瘤缺乏因子2(absent in melanoma 2,AIM2)和白三烯B4(leukotriene B4,LTB4)水平与急性缺血性脑卒中(acute ischemic stroke,AIS)患者预后的相关性。方法收集2020年2月~2021年2月期间于西安交通大学第一附属医院、西...目的探讨血清黑色素瘤缺乏因子2(absent in melanoma 2,AIM2)和白三烯B4(leukotriene B4,LTB4)水平与急性缺血性脑卒中(acute ischemic stroke,AIS)患者预后的相关性。方法收集2020年2月~2021年2月期间于西安交通大学第一附属医院、西安交通大学附属红会医院、咸阳市第一人民医院和泾阳县医院接受组织型纤溶酶原激活剂(tissue plasminogen activator,tPA)进行静脉溶栓治疗的138例AIS患者的临床资料进行回顾性分析。收集患者治疗三月后的改良Rankin评分量表(modified Rankin rating scale,mRS)评价其神经功能情况。依据mRS评分将AIS患者分为预后良好组(mRS评分≤2分,n=87)和预后不良组(mRS评分>2分,n=51)。采用酶联免疫吸附试验检测血清AIM2和LTB4水平。收集患者入院时的美国国立卫生研究院卒中患者神经功能缺损(neurological deficits in stroke patients at the National Institutes of Health,NIHSS)评分、梗死体积和侧支循环建立状况等信息。分析血清AIM2和LTB4水平、入院NIHSS评分、梗死体积和侧支循环建立状况与AIS患者预后的相关性。建立多因素Logistic回归模型分析rt-PA静脉溶栓后AIS患者预后不良的危险因素。结果与预后良好组比较,预后不良组的血清AIM2(1161.51±338.56pg/ml vs 964.77±171.94pg/ml)和LTB4水平(137.99±35.49pg/ml vs 117.85±21.60pg/ml)明显增高,差异具有统计学意义(t=4.638,4.148,均P<0.01)。Logistic回归分析发现AIS患者血清AIM2和LTB4水平增高、梗死体积增大、入院NIHSS评分增高及侧支循环建立状况较差均为AIS患者预后不良的独立危险因素(均P<0.05)。相关性分析显示AIS患者的血清AIM2和LTB4水平分别与梗死体积和入院NIHSS评分呈正相关性(r=0.374,0.334;0.233,0.304,均P<0.05)。AIM2和LTB4水平增高患者的侧支循环建立状况较差(均P<0.01)。受试者工作特征(receiver operating characteristic,ROC)曲线分析显示AIM2,LTB4及联合检测诊断AIS预后不良的曲线下面积(area under curve,AUC)分别为0.706(95%CI:0.607~0.806,P=0.000),0.745(95%CI:0.655~0.835,P=0.000)和0.740(95%CI:0.648~0.833,P=0.000);约登系数分别为0.424,0.386和0.422;敏感度和特异度分别为60.80%,81.60%;62.70%,75.90%;68.60%,75.80%。AIM2和LTB4诊断AIS预后不良的截断值分别为1065.93pg/ml和130.68pg/ml。结论血清AIM2和LTB4水平增高可能增加AIS患者rt-PA静脉溶栓后预后不良的风险,因此检测患者血清AIM2和LTB4水平可以为AIS患者的预后评估提供依据。展开更多
黑色素瘤缺乏因子-2(Absent in melanoma-2,AIM2)是存在于细胞质中的模式识别受体,它能够识别内源性或外源性的双链DNA并组装一种称为炎症小体的蛋白聚合物,介导白介素-1β(Interleukin-1β,IL-1β)、白介素-18(Interleukin-18,IL-18)...黑色素瘤缺乏因子-2(Absent in melanoma-2,AIM2)是存在于细胞质中的模式识别受体,它能够识别内源性或外源性的双链DNA并组装一种称为炎症小体的蛋白聚合物,介导白介素-1β(Interleukin-1β,IL-1β)、白介素-18(Interleukin-18,IL-18)的成熟与释放,促使细胞发生炎症性的程序性死亡—细胞焦亡。AIM2对外源性DNA的识别有助于宿主抵抗各类病原微生物的感染,例如各种细菌、病毒、真菌以及寄生虫。本文就AIM2炎症小体在感染中的作用机制研究进展进行综述。展开更多
纤维化发生于机体多种器官组织,持续进展的纤维化改变可导致组织结构被破坏并影响正常功能,甚至引起器官衰竭而死亡,如肺纤维化、心力衰竭、慢性肾病、肺动脉瓣关闭不全等。但目前尚无有效防治策略。慢性持续性炎性反应是纤维化进展的...纤维化发生于机体多种器官组织,持续进展的纤维化改变可导致组织结构被破坏并影响正常功能,甚至引起器官衰竭而死亡,如肺纤维化、心力衰竭、慢性肾病、肺动脉瓣关闭不全等。但目前尚无有效防治策略。慢性持续性炎性反应是纤维化进展的重要机制,近年来发现的黑色素瘤缺乏因子2(absent in melanoma 2,AIM2)炎症小体是一种胞质内多蛋白复合物,通过识别双链DNA(dsDNA)激活并介导炎症因子的成熟释放,所引起的炎性反应可以调控多种通路进而诱导纤维化。本文针对AIM2在纤维化疾病中的最新研究进展作一综述,以期为纤维化的治疗和干预提供新的靶点。展开更多
目的:观察急性脑梗死患者血清黑素瘤缺乏因子2 (absent in melanoma 2,AIM2)水平的变化及意义。方法:选取2020年1月—2021年4月收治于浙江大学医学院附属第四医院的186例急性脑梗死患者作为病例组,选取同期64例健康体检者作为对照组,采...目的:观察急性脑梗死患者血清黑素瘤缺乏因子2 (absent in melanoma 2,AIM2)水平的变化及意义。方法:选取2020年1月—2021年4月收治于浙江大学医学院附属第四医院的186例急性脑梗死患者作为病例组,选取同期64例健康体检者作为对照组,采用酶联免疫吸附法测定其血清AIM2水平,比较AIM2水平在两组患者之间的差异,并分析AIM2水平与患者神经功能缺损严重程度及预后的关系。结果:病例组血清AIM2水平高于对照组,差异有统计学意义(P<0.05);血清AIM2水平在NIHSS评分轻度组、中度组、重度组中逐渐升高,差异有统计学意义(H=120.17,P<0.05),AIM2水平与NIHSS评分呈正相关,差异有统计学意义(r=0.705,P<0.05);预后不良组血清AIM2水平明显高于预后良好组,差异有统计学意义(Z=6.387,P<0.05),AIM2水平与mRS评分呈正相关,差异有统计学意义(r=0.654,P<0.05),ROC曲线显示AIM2在协助判断急性脑梗死患者预后方面具有一定的价值,差异有统计学意义(P=0.003)。结论:血清AIM2可能参与了急性脑梗死的发生、发展,其水平在一定程度上有利于协助评估急性脑梗死患者神经功能损害的严重程度,并可以预测预后。展开更多
目的人类干扰素诱导基因家族之一的人类干扰素诱导蛋白(absent in melanoma 2,AIM2)被视为抑癌基因,但目前其抑癌机制仍不清楚。文中研究AIM2诱发乳腺癌细胞凋亡的分子机制。方法建立Tet-Off诱导模式系统来诱发AIM2大量表达,MCF-7 t TA-...目的人类干扰素诱导基因家族之一的人类干扰素诱导蛋白(absent in melanoma 2,AIM2)被视为抑癌基因,但目前其抑癌机制仍不清楚。文中研究AIM2诱发乳腺癌细胞凋亡的分子机制。方法建立Tet-Off诱导模式系统来诱发AIM2大量表达,MCF-7 t TA-AIM2细胞为实验组,MCF-7 t TA-Luc细胞为对照组。Western blot检测AIM2在乳腺癌细胞株的表达及亚细胞定位,XTT assay分析AIM2对细胞增殖的影响。应用膜联蛋白V-FITC和碘化丙啶染色行检测细胞凋亡,Western blot检测细胞凋亡的机制。结果文中建立的Tet-Off诱导系统可使t TA结合到TRE,从而促进AIM2基因转录,进而使AIM2蛋白大量表达。在诱导4 d后,可在细胞质及细胞核中检测到AIM2的表达,随诱导天数的增加其表达量增加。AIM2表达于细胞质及细胞核中。由XTT assay可知,MCF-7 t TA-AIM2细胞株在诱导6 d后生长速率减慢。诱导AIM2大量表达后,其FITC荧光凋亡百分比显著增加(2.36%vs 14.45%,P<0.01)。AIM2大量表达后抑制抗凋亡蛋白-Bcl-x L表达,增加促凋亡蛋白-Bad、Bax,并且活化caspases进而造成DNA修复蛋白PARP裂解。结论在乳腺癌Tet-Off诱导系统中,AIM2影响细胞增殖,刺激线粒体促使细胞走向凋亡。展开更多
基金supported by the Gusu Medical Key Talent Project of Suzhou City of China(GSWS2020005)the New Pharmaceutics and Medical Apparatuses Project of Suzhou City of China(SLJ2021007)+3 种基金the Suzhou City Key Clinical Disease Diagnosis and Treatment Technology Special Project,China(LCZX202129)Wujiang Science and Educational Health Revitalization Fund Project,Suzhou,China(WWK202015)the Scientific Research Project of Suzhou Ninth People’s Hospital,Suzhou,China(YK202008)and Suzhou“Science and Education”Youth Science and Technology Project,Suzhou,China(KJXW2020075).
文摘Colorectal cancer(CRC)stands among the top prevalent cancers worldwide and holds a prominent position as a major contributor to cancer-related mortality globally.Absent in melanoma 2(AIM2),a constituent of the interferoninducible hematopoietic interferon-inducible nuclear antigens with 200 amino acid repeats protein family,contributes to both cancer progression and inflammasome activation.Despite this understanding,the precise biological functions and molecular mechanisms governed by AIM2 in CRC remain elusive.Consequently,this study endeavors to assess AIM2’s expression levels,explore its potential antitumor effects,elucidate associated cancer-related processes,and decipher the underlying signaling pathways in CRC.Our findings showed a reduced AIM2 expression in most CRC cell lines.Elevation of AIM2 levels suppressed CRC cell proliferation and migration,altered cell cycle by inhibiting G1/S transition,and induced cell apoptosis.Further research uncovered the participation of P38 mitogen-activated protein kinase(P38MAPK)in AIM2-mediated modulation of CRC cell apoptosis and proliferation.Altogether,our achievements distinctly underscored AIM2’s antitumor role in CRC.AIM2 overexpression inhibited proliferation and migration and induced apoptosis of CRC cells via activating P38MAPK signaling pathway,indicating AIM2 as a prospective and novel therapeutic target for CRC.
基金supported by the National Natural Science Foundation of China,No.81772321(to HZL),81571194(to HZL),81471277(to JGH)a grant from the Key Program of Anhui Province for Outstanding Talents in Universities in China,No.gxbjZD2016071(to HZL),2014H012(to HZL)
文摘In traumatic brain injury, absent in melanoma 2(AIM2) has been demonstrated to be involved in pyroptotic neuronal cell death. Although the pathophysiological mechanism of spinal cord injury is similar to that of brain injury, the expression and cellular localization of AIM2 after spinal cord injury is still not very clear. In the present study, we used a rat model of T9 spinal cord contusive injury, produced using the weight drop method. The rats were randomly divided into 1-hour, 6-hour, 1-day, 3-day and 6-day(post-injury time points) groups. Sham-operated rats only received laminectomy at T9 without contusive injury. Western blot assay revealed that the expression levels of AIM2 were not significantly different among the 1-hour, 6-hour and 1-day groups. The expression levels of AIM2 were markedly higher in the 1-hour, 6-hour and 1-day groups compared with the sham, 3-day and 7-day groups. Double immunofluorescence staining demonstrated that AIM2 was expressed by NeuN+(neurons), GFAP+(astrocytes), CNPase+(oligodendrocytes) and CD11 b+(microglia) cells in the sham-operated spinal cord. In rats with spinal cord injury, AIM2 was also found in CD45+(leukocytes) and CD68+(activated microglia/macrophages) cells in the spinal cord at all time points. These findings indicate that AIM2 is mainly expressed in neurons, astrocytes, microglia and oligodendrocytes in the normal spinal cord, and that after spinal cord injury, its expression increases because of the infiltration of leukocytes and the activation of astrocytes and microglia/macrophages.
文摘目的探讨血清黑色素瘤缺乏因子2(absent in melanoma 2,AIM2)和白三烯B4(leukotriene B4,LTB4)水平与急性缺血性脑卒中(acute ischemic stroke,AIS)患者预后的相关性。方法收集2020年2月~2021年2月期间于西安交通大学第一附属医院、西安交通大学附属红会医院、咸阳市第一人民医院和泾阳县医院接受组织型纤溶酶原激活剂(tissue plasminogen activator,tPA)进行静脉溶栓治疗的138例AIS患者的临床资料进行回顾性分析。收集患者治疗三月后的改良Rankin评分量表(modified Rankin rating scale,mRS)评价其神经功能情况。依据mRS评分将AIS患者分为预后良好组(mRS评分≤2分,n=87)和预后不良组(mRS评分>2分,n=51)。采用酶联免疫吸附试验检测血清AIM2和LTB4水平。收集患者入院时的美国国立卫生研究院卒中患者神经功能缺损(neurological deficits in stroke patients at the National Institutes of Health,NIHSS)评分、梗死体积和侧支循环建立状况等信息。分析血清AIM2和LTB4水平、入院NIHSS评分、梗死体积和侧支循环建立状况与AIS患者预后的相关性。建立多因素Logistic回归模型分析rt-PA静脉溶栓后AIS患者预后不良的危险因素。结果与预后良好组比较,预后不良组的血清AIM2(1161.51±338.56pg/ml vs 964.77±171.94pg/ml)和LTB4水平(137.99±35.49pg/ml vs 117.85±21.60pg/ml)明显增高,差异具有统计学意义(t=4.638,4.148,均P<0.01)。Logistic回归分析发现AIS患者血清AIM2和LTB4水平增高、梗死体积增大、入院NIHSS评分增高及侧支循环建立状况较差均为AIS患者预后不良的独立危险因素(均P<0.05)。相关性分析显示AIS患者的血清AIM2和LTB4水平分别与梗死体积和入院NIHSS评分呈正相关性(r=0.374,0.334;0.233,0.304,均P<0.05)。AIM2和LTB4水平增高患者的侧支循环建立状况较差(均P<0.01)。受试者工作特征(receiver operating characteristic,ROC)曲线分析显示AIM2,LTB4及联合检测诊断AIS预后不良的曲线下面积(area under curve,AUC)分别为0.706(95%CI:0.607~0.806,P=0.000),0.745(95%CI:0.655~0.835,P=0.000)和0.740(95%CI:0.648~0.833,P=0.000);约登系数分别为0.424,0.386和0.422;敏感度和特异度分别为60.80%,81.60%;62.70%,75.90%;68.60%,75.80%。AIM2和LTB4诊断AIS预后不良的截断值分别为1065.93pg/ml和130.68pg/ml。结论血清AIM2和LTB4水平增高可能增加AIS患者rt-PA静脉溶栓后预后不良的风险,因此检测患者血清AIM2和LTB4水平可以为AIS患者的预后评估提供依据。
文摘黑色素瘤缺乏因子-2(Absent in melanoma-2,AIM2)是存在于细胞质中的模式识别受体,它能够识别内源性或外源性的双链DNA并组装一种称为炎症小体的蛋白聚合物,介导白介素-1β(Interleukin-1β,IL-1β)、白介素-18(Interleukin-18,IL-18)的成熟与释放,促使细胞发生炎症性的程序性死亡—细胞焦亡。AIM2对外源性DNA的识别有助于宿主抵抗各类病原微生物的感染,例如各种细菌、病毒、真菌以及寄生虫。本文就AIM2炎症小体在感染中的作用机制研究进展进行综述。
文摘纤维化发生于机体多种器官组织,持续进展的纤维化改变可导致组织结构被破坏并影响正常功能,甚至引起器官衰竭而死亡,如肺纤维化、心力衰竭、慢性肾病、肺动脉瓣关闭不全等。但目前尚无有效防治策略。慢性持续性炎性反应是纤维化进展的重要机制,近年来发现的黑色素瘤缺乏因子2(absent in melanoma 2,AIM2)炎症小体是一种胞质内多蛋白复合物,通过识别双链DNA(dsDNA)激活并介导炎症因子的成熟释放,所引起的炎性反应可以调控多种通路进而诱导纤维化。本文针对AIM2在纤维化疾病中的最新研究进展作一综述,以期为纤维化的治疗和干预提供新的靶点。
文摘目的:观察急性脑梗死患者血清黑素瘤缺乏因子2 (absent in melanoma 2,AIM2)水平的变化及意义。方法:选取2020年1月—2021年4月收治于浙江大学医学院附属第四医院的186例急性脑梗死患者作为病例组,选取同期64例健康体检者作为对照组,采用酶联免疫吸附法测定其血清AIM2水平,比较AIM2水平在两组患者之间的差异,并分析AIM2水平与患者神经功能缺损严重程度及预后的关系。结果:病例组血清AIM2水平高于对照组,差异有统计学意义(P<0.05);血清AIM2水平在NIHSS评分轻度组、中度组、重度组中逐渐升高,差异有统计学意义(H=120.17,P<0.05),AIM2水平与NIHSS评分呈正相关,差异有统计学意义(r=0.705,P<0.05);预后不良组血清AIM2水平明显高于预后良好组,差异有统计学意义(Z=6.387,P<0.05),AIM2水平与mRS评分呈正相关,差异有统计学意义(r=0.654,P<0.05),ROC曲线显示AIM2在协助判断急性脑梗死患者预后方面具有一定的价值,差异有统计学意义(P=0.003)。结论:血清AIM2可能参与了急性脑梗死的发生、发展,其水平在一定程度上有利于协助评估急性脑梗死患者神经功能损害的严重程度,并可以预测预后。
文摘目的人类干扰素诱导基因家族之一的人类干扰素诱导蛋白(absent in melanoma 2,AIM2)被视为抑癌基因,但目前其抑癌机制仍不清楚。文中研究AIM2诱发乳腺癌细胞凋亡的分子机制。方法建立Tet-Off诱导模式系统来诱发AIM2大量表达,MCF-7 t TA-AIM2细胞为实验组,MCF-7 t TA-Luc细胞为对照组。Western blot检测AIM2在乳腺癌细胞株的表达及亚细胞定位,XTT assay分析AIM2对细胞增殖的影响。应用膜联蛋白V-FITC和碘化丙啶染色行检测细胞凋亡,Western blot检测细胞凋亡的机制。结果文中建立的Tet-Off诱导系统可使t TA结合到TRE,从而促进AIM2基因转录,进而使AIM2蛋白大量表达。在诱导4 d后,可在细胞质及细胞核中检测到AIM2的表达,随诱导天数的增加其表达量增加。AIM2表达于细胞质及细胞核中。由XTT assay可知,MCF-7 t TA-AIM2细胞株在诱导6 d后生长速率减慢。诱导AIM2大量表达后,其FITC荧光凋亡百分比显著增加(2.36%vs 14.45%,P<0.01)。AIM2大量表达后抑制抗凋亡蛋白-Bcl-x L表达,增加促凋亡蛋白-Bad、Bax,并且活化caspases进而造成DNA修复蛋白PARP裂解。结论在乳腺癌Tet-Off诱导系统中,AIM2影响细胞增殖,刺激线粒体促使细胞走向凋亡。
