PI3K/AKT信号通路与白血病

白血病（leukemia）是一种源于骨髓的造血干细胞恶性增殖性疾病。PI3K/AKT信号通路是一种胞内传导的信号通路,与肿瘤细胞生存息息相关。本文就PI3K/AKT信号通路与白血病的相关性进行综述。     

PI3K/AKT信号通路在银屑病发病机制中的研究进展

银屑病是一种免疫介导的多因素炎症性皮肤病,以表皮角质形成细胞异常增殖、毛细血管扩张、中性粒细胞浸润为主要病理表现。磷脂酰肌醇3-激酶（phosphatidylinositol 3-kinase,PI3K）/蛋白激酶B（protein kinase B,AKT）信号通路在表皮细胞增殖、细胞自噬、血管生成、脂质代谢等过程中...     

PI3K/AKT信号通路在肿瘤调控中的免疫作用及分子机制

磷脂酰肌醇3-激酶(phosphatidylinositol-3-kinases,PI3K)/蛋白质丝氨酸苏氨酸激酶(protein-serine-threonine kinase,AKT)信号通路是具有酶活性的细胞内信号转导通路。研究发现人类的多种肿瘤如胃癌、大肠癌、乳腺癌、肝癌、肾癌等均与PI3K/AKT信号通路密切相关,且PI3K/AKT信号通路中多种上下游分子的改变均可影响肿瘤的发生和发展。PI3K/AKT信号通路可从凋亡、炎性反应、免疫等多方面影响肿瘤的发生发展。笔者现对PI3K/AKT信号通路和其相关上下游免疫分子之间相互作用对肿瘤影响做一综述。     

青蒿素基于PI3K/AKT信号通路对人急性髓系白血病细胞凋亡的作用机制

目的分析青蒿素基于磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)信号通路对人急性髓系白血病(AML)细胞凋亡的作用机制。方法以44例AML患儿原代细胞及K562细胞株4株为研究样本,平均分为对照组、实验组(分别加入12.5、25.0、50.0μg/ml青蒿琥酯),细胞计数法观察72 h内细胞生长趋势,采用流式细胞术检测不同浓度青蒿琥酯对细胞凋亡的影响,免疫印迹法检测细胞凋亡相关蛋白(PI3K、AKT、P-AKT、Bcl-2、Bax、caspase-3、PTEN)的表达。结果 AML原代细胞、细胞株K562 24 h内细胞存活率≥80%,对照组AML原代细胞、细胞株K562 48～72 h细胞存活率仍≥70%,而实验组AML原代细胞、细胞株K562培养48 h细胞存活率均降至50%以下,且明显低于对照组(P<0.05);青蒿琥酯呈浓度依赖性诱导人AML原代细胞及K562细胞株凋亡,且25.0μg/ml组、50.0μg/ml组的细胞存活率低于12.5μg/ml组及对照组(P<0.05),25.0μg/ml组、50.0μg/ml组的细胞存活率比较差异无统计学意义(P>0.05)。培养48 h后,实验组原代细胞及K562细胞株的PI3K、P-AKT、Bcl-2均明显下调(P<0.05),而Bax、caspase-3、PTEN表达上调(P<0.05),且青蒿琥酯浓度为25.0μg/ml组各项指标变化最明显,AKT无明显变化(P>0.05)。结论青蒿素类衍生物青蒿琥酯可经PI3K/AKT信号通路调节其Bcl-2、Bax、caspase-3、PTEN等凋亡相关蛋白表达,促进人AML细胞凋亡,25μg/ml浓度时效果较佳。     

PI3K/AKT信号通路与miR-203在食管癌中的研究进展

食管癌是原发食管上皮的恶性肿瘤,发病机制复杂.在食管癌中,磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)是参与其中并经常被激活的信号通路之一,其异常激活可促进食管癌的发展.miR-203为小分子非编码RNA,长度为19～22个核苷酸,在多种恶性组织中表达异常.miR-203可通过与靶基因的3'UTR结合,在转录后...     

雷公藤红素通过PI3K/AKT/mTOR信号通路对胃癌MFC细胞增殖和凋亡的影响

目的研究雷公藤红素对胃癌MFC细胞内PI3K/AKT/mTOR信号通路的影响及其对胃癌MFC细胞增殖的抑制和促凋亡作用机制。方法分别设置对照组和雷公藤红素低、中、高剂量(5、10、20 mmol/L)组,采用MTT法检测雷公藤红素对胃癌MFC细胞增殖的影响;采用流式细胞技术检测雷公藤红素对胃癌MFC细胞周期的影响及MFC细胞凋亡的情况;Western blotting检测雷公藤红素对胃癌MFC细胞内凋亡相关蛋白Bax、Bcl-2和PI3K、AKT和mTOR蛋白表达的影响;实时定量PCR检测雷公藤红素对胃癌MFC细胞内PI3K、AKT和mTORm RNA表达的影响。结果与对照组比较,雷公藤红素能够呈剂量相关性地显著抑制胃癌MFC细胞的增殖(P0.05);与对照组比较,雷公藤红素能够呈剂量相关性地显著引起MFC细胞G2/M期阻滞(P0.05);与对照组比较,雷公藤红素能够呈剂量相关性地显著促进MFC细胞的凋亡(P0.05);与对照组比较,雷公藤红素能够呈剂量相关性地显著抑制MFC细胞内抗凋亡蛋白Bcl-2蛋白和PI3K、AKT、mTOR蛋白的表达(P0.05),显著促进MFC细胞内促凋亡蛋白Bax的表达(P0.05);与对照组比较,雷公藤红素能够呈剂量相关性地显著抑制MFC细胞内PI3K、AKT和mTORm RNA的表达(P0.05)。结论雷公藤红素能够抑制胃癌MFC细胞的增殖并促进胃癌MFC细胞凋亡,其作用机制可能是通过抑制胃癌MFC细胞内PI3K/AKT/mTOR信号通路中PI3K、AKT、mTOR等蛋白的表达而抑制胃癌MFC细胞的增殖,进而促进胃癌MFC细胞内促凋亡蛋白Bax的表达,同时抑制抗凋亡蛋白Bcl-2的表达,从而促进胃癌MFC细胞凋亡。     

PI3K/AKT/mTOR信号通路抑制剂在卵巢癌治疗中的研究进展

卵巢癌是女性生殖系统最致命的恶性肿瘤。目前,针对卵巢癌的规范治疗方案是肿瘤细胞减灭术辅以紫杉醇/铂类联合化疗,然而大多数晚期卵巢癌患者最终因对化疗药物耐药而复发。PI3K/AKT/m TOR信号通路作为一条重要的原癌基因通路,在卵巢癌中激活并在卵巢癌的增殖、侵袭、细胞周期进程、血管形成及耐药中发挥着重要的作用,抑制该通路是卵巢癌的一个潜在治疗方法。对PI3K/AKT/m TOR信号通路抑制剂在卵巢癌治疗中的研究进展进行综述。     

莪术醇通过调控PI3K/AKT通路促进人肝癌HepG2细胞凋亡

目的探讨莪术醇促进人肝癌HepG2细胞凋亡的作用是否与PI3K/AKT通路有关。方法采用MTT法检测不同浓度(0、10、25、50、100μmol·L~(-1))莪术醇干预HepG2细胞24、48 h的增殖抑制率,Hoechst 33258染色法观察细胞核凋亡形态,Western blot法检测不同浓度莪术醇及PI3K/AKT通路阻断剂LY294002对HepG2细胞p-PI3K、p-AKT、Caspase-3蛋白表达的影响。结果莪术醇对HepG2细胞的增殖有明显抑制作用,呈浓度依赖性,但干预48 h对比24 h差异无统计学意义;Hoechst 33258染色发现,莪术醇干预后,同一视野下细胞数目明显减少,细胞透亮,部分细胞核碎裂,核固缩,呈现典型的凋亡形态学特征;Western blot结果显示,莪术醇能显著降低细胞p-PI3K、p-AKT蛋白的表达,上调凋亡执行蛋白Caspase-3的表达,与LY294002联用后表现出良好的协同作用,对各蛋白表达的调控较单独用药更加明显。结论莪术醇能通过抑制PI3K/AKT通路诱导人肝癌HepG2细胞凋亡。     

PI3K/AKT/mTOR信号通路抑制剂在宫颈癌治疗中的研究进展

宫颈癌是女性常见恶性肿瘤之一。针对局部晚期及复发转移的宫颈癌患者尚未有令人满意的治疗手段,因此探索和发展更有效的治疗方案具有重要的意义。PI3K/AKT/m TOR信号通路在人类子宫颈癌细胞的增殖、分化和凋亡中具有重要的调节作用,有希望成为开发宫颈癌治疗药物的新型靶标。综述了近年来PI3K/AKT/m TOR信号通路的单一及双重靶点抑制剂针对宫颈癌的临床前及临床研究情况,包括PI3K抑制剂(wortmannin、LY294002、吲哚-3-甲醇)、AKT抑制剂(SC-66、MK-2206、木黄酮、冬凌草甲素和雷公藤)、m TOR抑制剂(替西罗莫司和依维莫司)及双重靶点抑制剂(GSK2126458、BEZ235、BGT226、PF04691502、GDC-0980和PKI-587)等。     

白杨素通过PI3K/AKT信号通路抑制LPS诱导的软骨细胞自噬

Aim To explore the effect of chrysin on chondrocyte autophagy in rat chondrocyte osteoarthritis model induced by lipopolysaccharide and its mechanism. Methods Normal articular cartilage cells of 10 SPF SD rats were isolated and cultured in vitro, and the autophagy of rat chondrocytes was induced by LPS. The experiment was divided into blank control group, LPS group, chrysin (CHR) group and LPS + CHR group, the activity of cells in each group was detected by CCK-8 method, the mitochondrial membrane potential of cells in each group was detected by Rhodaminel23, and the protein expression of PI3K, AKT, p-PI3K, p-AKT, Beclin-1 and LC3 II in cells of each group was detected by reactive oxygen species, Western blot method of DCFH-DA. Results Chrysin could inhibit the autophagy induced by LPS, especially when the concentration of chrysin was 10 mmol · L^-1. Chrysin could inhibit the increase of reactive oxygen species (ROS) induced by LPS induced by LPS, inhibit the decrease of mitochondrial membrane potential after injury, and inhibit the expression of Beclin-1 and LC3 II protein and the phosphorylation of PI3K and AKT. Conclusions Chrysin may inhibit autophagy by inhibiting PI3K/AKT signaling pathway and down-regulating the expression of autophagy proteins Beclin-1 and LC3 II, thus protecting chondrocytes. © 2021 Publication Centre of Anhui Medical University. All rights reserved.     

Amiloride sensitizes human pancreatic cancer cells to erlotinib in vitro through inhibition of the PI3K/AKT signaling pathway

Aim:

Blockade of EGFR by EGFR tyrosine kinase inhibitors such as erlotinib is insufficient for effective treatment of human pancreatic cancer due to independent activation of the Akt pathway, while amiloride, a potassium-sparing diuretic, has been found as a potential Akt inhibitor. The aim of this study was to investigate the anticancer effects of combined amiloride with erlotinib against human pancreatic cancer cells in vitro.

Methods:

Cell proliferation, colony formation, cell cycle and apoptosis were analyzed in 4 human pancreatic cancer cell lines Bxpc-3, PANC-1, Aspc-1 and CFPAC-1 treated with erlotinib or amiloride alone, or in their combination. The synergistic analysis for the effects of combinations of amiloride and erlotinib was performed using Chou-Talalay''s combination index isobolographic method.

Results:

Amiloride (10, 30, and 100 μmol/L) concentration-dependently potentiated erlotinib-induced inhibition of cell proliferation and colony formation in the 4 pancreatic cancer cell lines. Isobolographic analysis confirmed that combinations of amiloride and erlotinib produced synergistic cytotoxic effects. Amiloride significantly potentiated erlotinib-induced G₀/G₁ cell-cycle arrest and apoptosis in Bxpc-3 and PANC-1 cells. Amiloride inhibited EGF-stimulated phorsphorylation of AKT, and significantly enhanced erlotinib-induced downregulation of phorsphorylation of EGFR, AKT, PI3K P85 and GSK 3β in Bxpc-3 and PANC-1 cells.

Conclusion:

Amiloride sensitizes human pancreatic cancer cells to erlotinib in vitro through inhibition of the PI3K/AKT signaling pathway. Treatment of pancreatic cancer patients with combination of erlotinib and amiloride merits further investigation.     

Role of PI3K/AKT/mTOR signaling pathway in DBP-induced apoptosis of testicular sertoli cells in vitro

Dibutyl phthalate (DBP) has significant male reproductive toxicity, and the Sertoli cells are the target cells of DBP. This study was to investigate the injury effect induced by DBP on rat testicular Sertoli cells in vitro. MTT results showed that DBP can significantly reduce the survival rate of Sertoli cells; Hoechst staining results showed that the Sertoli cells treated with DBP emerged with typical morphological characteristics of apoptosis, nuclear condensation and chromatin condensation; flow cytometry results showed that DBP significantly increased the apoptotic rate of Sertoli cells, and dose-dependent; Western blotting showed that the expression of PTEN protein in Sertoli cells was significantly higher than that in the control group after treated with different concentrations of DBP for 24 h, while the expression of p-PI3K1, p-AKT, p70S6K and 4E-BP1 protein in the PI3K/AKT/mTOR signal pathway were significantly decreased. It is speculated that PTEN/PI3K/AKT/mTOR signaling pathway plays an important role in DBP-induced apoptosis of testicular Sertoli cells in rats.     

PI3K/AKT信号通路在心房颤动中的研究进展

心房颤动（房颤）作为最常见的快速性心律失常,目前主要的治疗手段为抗凝、控制心室率、维持窦性心律。然而房颤的发生机制尚未阐明,上述治疗仍具有一定的局限性。磷脂酰肌醇3-激酶（PI3K）/蛋白激酶（AKT）信号转导通路是参与房颤发生发展的重要通路,其可以通过介导心房纤维化、炎症反应、氧化应激、神经内分泌功能调节参与房颤发生发展的病理生理过程。深入研究PI3K/AKT信号转导通路在房颤中的作用,可为房颤的预防、治疗及预后评估提供有价值的指导。     

扁蓄苷对人乳腺癌MDA-MB-231细胞凋亡、周期及PI3K/AKT信号通路的影响

目的探讨扁蓄苷对乳腺癌MDA-MB-231细胞的凋亡、周期及PI3K/AKT信号通路的影响。方法以不同浓度的萹蓄苷作用于体外生长至对数期的MDA-MB-231细胞48 h后,采用噻唑蓝染色(MTT)法检测扁蓄苷对细胞增殖的影响,Hoechst 33258染色观察细胞染色质固缩情况,流式细胞术检测细胞周期,Western-blot检测PI3K/AKT信号通路核心蛋白PI3K、p-PI3K、AKT、p-AKT表达水平,RT-PCR技术检测通路下游细胞凋亡蛋白Bcl-2、Bcl-xl及周期相关蛋白CDK2基因表达情况。结果不同浓度的扁蓄苷(6.25、12.5、25、50、100μmol·L~(-1))作用于MDA-MB-231细胞48 h后,细胞增殖活性受到抑制(P <0.01),且具有浓度依赖性;扁蓄苷(12.5、50、100μmol·L~(-1))作用细胞48 h后,细胞核染色质固缩;当扁蓄苷浓度为50μmol·L~(-1)时,S期细胞所占百分比显著增高(P <0.05),当扁蓄苷浓度为100μmol·L~(-1)时,G2/M期细胞所占百分比显著增高(P <0.05);随着扁蓄苷浓度的增加,通路核心位点PI3K、p-PI3K、AKT、p-AKT蛋白表达水平明显降低(P <0.01),细胞凋亡相关蛋白Bcl-2和Bcl-xl、细胞周期蛋白CDK2基因表达水平下调(P <0.05)。结论扁蓄苷可抑制乳腺癌MDA-MB-231细胞增殖,使细胞周期阻滞于S期、G2/M期,并诱导细胞凋亡。其机制可能是通过抑制PI3K/AKT信号通路下调Bcl-2、Bcl-xl、及CDK2基因表达进而诱导人乳腺癌MDA-MB-231细胞凋亡。     

Furazolidone induces apoptosis through activating reactive oxygen species-dependent mitochondrial signaling pathway and suppressing PI3K/Akt signaling pathway in HepG2 cells

Furazolidone (FZD), a synthetic nitrofuran with a broad spectrum of antimicrobial activities, has been shown to be genotoxic and potentially carcinogenic in several types of cells. However, the proper molecular mechanisms of FZD toxicity remain unclear. This study was aimed to explore the effect of FZD on apoptosis in HepG2 cells and uncover signaling pathway underlying the cytotoxicity of FZD. The results showed that FZD induced apoptosis in HepG2 cells in a dose-dependent manner characterized by nuclei morphology changes, cell membrane phosphatidylserine translocation, poly (ADP-ribose) polymerase (PARP) cleavage and a cascade activation of caspase-9 and -3. FZD could enhance reactive oxygen species (ROS) generation, up-regulate Bax/Bcl-2 ratio, disrupt mitochondrial membrane potential (MMP) and subsequently cause cytochrome c release. Both ROS scavenger (N-acetyl cysteine, NAC) and caspase inhibitors suppressed FZD-induced apoptosis. Furthermore, NAC attenuated FZD-induced ROS generation and mitochondrial dysfunction. Meanwhile, FZD treatment inhibited both the activation and expression of Akt, and PI3K/Akt inhibitor LY294002 promoted FZD-induced apoptosis. On the contrary, PI3K/Akt activator insulin-like growth factor-1 (IGF-1) attenuated lethality of FZD in HepG2 cells. In conclusion, it is first demonstrated that FZD-induced apoptosis in HepG2 cells might be mediated through ROS-dependent mitochondrial signaling pathway and involves PI3K/Akt signaling.