顺铂通过抑制PI3K/AKT/mTOR信号通路诱导子宫内膜癌Ishikawa细胞自噬

目的：探讨顺铂对子宫内膜癌Ishikawa细胞自噬的影响,并初步探讨PI3K/AKT/mTOR信号通路在其中的作用。方法：透射电镜观察自噬泡形成,免疫荧光检测微管相关蛋白1轻链3融合蛋白II（microtubule-associated protein 1 light chain 3II,LC3II） 的荧光聚集情况。采用Westerblot检测mTOR通路中的PI3K、AKT及mTOR蛋白的表达。结果：顺铂（20μg/mL）能诱导Ishikawa细胞发生自噬,其中24h组明显高于12h组（P<0.05）;与对照组（20μg/mL-0h组）相比较,自噬相关蛋白-LC3的表达随着时间延长表达增加（P<0.05）。磷酸化AKT1、磷酸化mTOR及PI3Kp85蛋白表达水平随着时间延长表达下降。胰岛素样生长因子-1（insulin-like growth factors-1,IGF-1）与顺铂共培养组自噬小体及LC3蛋白表达少于顺铂组,但高于对照组。结论：顺铂可能通过抑制PI3K/AKT/mTOR信号通路,从而诱导子宫内膜癌细胞发生自噬。     

内质网激动剂调控PI3K/AKT/mTOR通路诱导人小细胞肺癌NCI-H446细胞凋亡

目的 检测内质网应激能否通过PI3K/AKT/mTOR通路对人小细胞肺癌NCI-H446细胞凋亡产生作用.方法 采用MTT法检测不同浓度衣霉素对人小细胞肺癌NCI-H446的细胞毒性,Annexin V/PI检测药物作用下人小细胞肺癌NCI-H446细胞凋亡情况,Western Blot检测PI3K/AKT/mTOR通路相关蛋白的表达.结果 衣霉素可抑制人小细胞肺癌NCI-H446细胞的活性,且呈时间和浓度依赖性.衣霉素能够激活内质网应激,抑制PI3K/AKT/mTOR信号通路,使PI3K、AKT、mTOR蛋白磷酸化下调,诱导细胞凋亡.结论 内质网激动剂能够调控PI3K/AKT/mTOR通路诱导人小细胞肺癌NCI-H446细胞凋亡.     

EphB1通过PI3K/AKT信号通路促进食管鳞状细胞癌EC-9706细胞增殖、迁移、侵袭并抑制其凋亡

目的:研究促红细胞生成素产肝细胞受体B1(erythropoietin-producing human hepatocellular receptor B1,EphB1)对食管鳞状细胞癌EC-9706细胞增殖、迁移、侵袭及凋亡的影响,并探索其可能的作用机制。方法:qRT-PCR法分析40对食管鳞状细胞癌手术患者的癌组织及邻近正常组织中EphB1表达情况,并分析其临床特征。在EC-9706细胞中分别转染si-EphB1 RNA和oe-EphB1 RNA及其阴性对照。通过qRT-PCR和蛋白免疫印迹实验检测转染效率;CCK-8实验分析EphB1对细胞活力的影响;Hoechst 33258染色和流式细胞学实验检测细胞凋亡;划痕愈合实验及Transwell侵袭实验明确细胞迁移及侵袭能力;蛋白免疫印迹实验检测EphB1蛋白、增殖相关蛋白［增殖细胞核抗原（proliferating cell nuclear antigen,PCNA）］、凋亡相关蛋白［Bad、Bcl-2、Caspase 3 及剪切型-Caspase 3（cleaved-Caspase 3）］、侵袭转移相关蛋白［基质金属蛋白酶9(matrix metalloproteinase-9,MMP-9)、基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2）、Snail、波形蛋白(Vimentin)、N-cadherin、E-cadherin］以及PI3K/AKT信号通路相关蛋白（PI3K、AKT、p-AKT）的表达水平。结果:EphB1在食管鳞状细胞癌组织及细胞系中高表达(P均＜0.05),EphB1的表达水平与食管鳞状细胞癌患者的TNM分期、有无淋巴结转移和远处转移具有显著相关性(P均＜0.05)。与对照组相比,通过细胞转染技术沉默EphB1和过表达EphB1使EC-9706细胞的增殖、迁移、侵袭能力明显降低或增强,并诱导或抑制细胞凋亡(P均＜0.05)。在蛋白水平上,si-EphB1和oe-EphB1处理EC-9706细胞48 h后,增殖相关蛋白PCNA蛋白表达水平分别显著降低或增加（P均＜0.05）,并分别增加或降低促凋亡相关蛋白Bad、cleaved-Caspase 3的表达水平（P均＜0.05）,下调或上调抗凋亡蛋白Bcl-2、Caspase 3的蛋白表达（P均＜0.05）,抑制或促进侵袭转移相关蛋白MMP-9、MMP-2、Snail、Vimentin、N-cadherin的蛋白活性,但却上调或下调 E-cadherin的表达水平（P均＜0.05）。同时,Western blotting实验结果还证实EphB1可诱导食管鳞状细胞癌EC-9706细胞中通路蛋白PI3K、p-AKT的活性增强（P均＜0.05）。结论:EphB1可能通过调控PI3K/AKT信号通路促进食管鳞状细胞癌EC-9706细胞的增殖、迁移及侵袭,并抑制其凋亡。     

PI3K/AKT/mTOR信号通路介导乳腺癌内分泌治疗耐药的研究进展

内分泌治疗在激素受体阳性乳腺癌患者中的地位越来越受到重视,可以明显改善患者预后.内分泌治疗耐药严重制约着其临床应用,但耐药机制仍不明确,目前认为多信号通路激活参与耐药形成,其中PI3K/AKT/mTOR信号通路在耐药机制中发挥重要作用.临床试验提示,在内分泌治疗的基础上阻断信号通路可以逆转耐药,研究结果令人鼓舞.本文对PI3K/AKT/mTOR信号通路在内分泌耐药机制中的作用进行综述.     

PI3K/AKT/mTOR信号通路抑制剂在淋巴瘤中的研究进展*

磷脂酰肌醇-3 激酶（phosphatidylinositol 3-kinase,PI 3K）- 蛋白激酶B（protein kinaseB ,PKB ,又称AKT ）- 雷帕霉素靶蛋白（mammalian target of  rapamycin,mTOR）信号通路与细胞的生长、增殖、分化、凋亡、代谢等密切相关,在多种实体肿瘤中已发现该信号通路的异常。近年来,以抑制该通路特定位点的靶向治疗已成为抗肿瘤的研究热点。许多该位点新型抑制剂也已进入淋巴瘤的临床试验中,本文就该通路在淋巴瘤中的活化状态及各个分子靶点抑制剂的研究进展做一综述。     

异莲心碱通过PI3K/Akt/mTOR信号通路影响结肠癌SW480细胞增殖、 凋亡和自噬

目的：探讨异莲心碱（Iso）通过PI3K/Akt/mTOR信号通路对结肠癌SW480细胞增殖、凋亡和自噬的影响。方法：用 10、20和40 μmol/L的Iso处理结肠癌SW480细胞,CCK-8法、流式细胞术和WB法分别检测Iso对细胞增殖活力、凋亡和自噬相关 蛋白LC3Ⅰ、LC3Ⅱ、p62表达的影响。然后,用20 μmol/L的Iso和25 μmol/L的PI3K激活剂740 Y-P分别处理SW480细胞,将细 胞分为对照组、740 Y-P组、Iso组和Iso+740 Y-P组,流式细胞术、WB法检测Iso和740 Y-P对各组细胞凋亡及细胞中LC3Ⅰ、LC3Ⅱ、 p62、PI3K、p-PI3K、 mTOR和p-mTOR蛋白表达的影响。结果：10、20和40 μmol/L的Iso处理后,SW480细胞增殖活力均显著下 降（均P<0.05）,细胞凋亡率均显著升高（均P<0.05）,LC3Ⅱ/LC3Ⅰ表达均显著上调（均P<0.05）,p26蛋白表达显著下调（P<0.05）。 Iso和740 Y-P处理后,与对照组相比,740 Y-P 组细胞凋亡率、LC3Ⅱ/LC3Ⅰ表达均显著下降（均P<0.05）,p26、p-PI3K/PI3K和 p-mTOR/mTOR 表达均显著升高（均 P<0.05）;Iso 组 细胞凋亡率、LC3Ⅱ/LC3Ⅰ表达升高（均 P<0.05）,p26、p-PI3K/PI3K和 p-mTOR/mTOR 表达均显著下降（均 P<0.05）;与 740 Y-P 组相比,Iso+740 Y-P 组细胞凋亡率、LC3Ⅱ/LC3Ⅰ表达升高（P<0.05）, p26、p-PI3K/PI3K和p-mTOR/mTOR表达均显著下降（均P<0.05）;与Iso组相比,Iso+740 Y-P组细胞凋亡率、LC3Ⅱ/LC3Ⅰ表达下 降（均P<0.05）,p26、p-PI3K/PI3K和p-mTOR/mTOR表达均显著升高（均P<0.05）。结论：Iso通过抑制PI3K/Akt/mTOR信号通路 抑制结肠癌SW480细胞增殖并诱导细胞凋亡和自噬。     

依维莫司治疗PI3K/AKT/mTOR通路突变难治性晚期乳腺癌1例

患者女,52岁,已绝经,2011年初发现右乳外上象限肿物约2 cm×3 cm,后肿物逐渐增大,皮肤红肿,右上肢及右手肿胀伴活动障碍,右腋下破溃、溢液,未重视及诊治.2015年10月患者首次入院,查体:右乳外上象限可及5 cm×5 cm肿物,固定质硬,橘皮样改变;右肩部、右上肢及右手肿胀,活动受限;右腋下多发肿大淋巴结,相互融合,局部皮肤破溃.CT示:1)考虑右乳癌,累及右侧胸壁及右肩部软组织;2)右腋下及右侧锁骨上下多发淋巴结肿大,考虑转移;3)肝方叶结节,考虑转移瘤.     

PI3K/AKT/mTOR信号通路抑制剂治疗结直肠癌的研究进展

PI3K/AKT/mTOR通路的异常活化在结直肠癌的发生发展中起到重要作用,以此通路为靶点的药物已成为结直肠癌治疗的研究热点,临床前和临床试验研究证明,针对PI3K/AKT/mTOR通路的多种抑制剂具有抗肿瘤活性。越来越多的临床数据显示,PTEN缺乏或PIK3CA基因突变对PI3K/AKT/mTOR通路抑制剂敏感,KRAS突变则预示着耐药;寻找针对这一通路抑制剂敏感的优势人群也成为结直肠癌的研究热点;此外,PI3K/AKT/mTOR通路也会影响常规治疗的疗效,因此PI3K/AKT/mTOR通路抑制剂联合细胞毒治疗方案在结直肠癌中可能起到协同作用。     

低表达DJ-1调控PI3K/AKT通路对肺癌细胞增殖、凋亡的影响

目的:探讨低表达DJ-1对肺癌细胞增殖凋亡及PI3K/AKT通路的影响。方法:采用Western blot检测肺癌细胞系中DJ-1蛋白的表达;以脂质体法转染干扰SK-MES-1细胞中DJ-1蛋白的表达后,MTT法检测细胞的增殖变化,流式细胞仪检测细胞的凋亡情况,Western blot检测细胞中p-AKT和AKT蛋白的表达水平;将PI3K/AKT通路抑制剂LY294002处理SK-MES-1细胞48 h后,MTT法和流式细胞仪分别检测细胞的增殖和凋亡情况,Western blot检测细胞中p-AKT和AKT蛋白的表达。结果:与正常肺上皮BEAS-2B细胞相比,肺腺癌A549细胞和肺鳞癌SK-MES-1细胞中DJ-1蛋白的相对表达量均显著升高,且SK-MES-1细胞中DJ-1蛋白的表达量高于A549细胞,差异均有统计学意义（P＜0.05）。转染后siRNA DJ-1组细胞中DJ-1蛋白的表达量明显低于对照组（P＜0.05）;与对照组相比,转染24 h后siRNA DJ-1组细胞的吸光值（OD值）变化不显著（P＞0.05）,而转染48 h和72 h后细胞的OD值明显降低（P＜0.05）;转染48 h后,与对照组相比,siRNA DJ-1组细胞的凋亡率显著升高（P＜0.05）,p-AKT/AKT值显著降低（P＜0.05）。SK-MES-1细胞经抑制剂LY294002处理48 h后,细胞的增殖凋亡趋势与下调DJ-1表达的结果相一致。结论:DJ-1在肺癌细胞中高表达,下调其表达能够抑制细胞增殖,促进细胞凋亡,其作用机制可能与PI3K/AKT信号通路有关。     

PI3K/AKT/mTOR通路抑制剂在膀胱癌中的研究进展

磷脂酰肌醇3-激酶(PI3K)/AKT/哺乳动物雷帕霉素靶标(mTOR)通路在人类肿瘤的恶性转化及其随后的生长、增殖和转移中起重要作用。临床前研究表明,PI3K/AKT/mTOR通路在膀胱癌中经常被激活。因此,这一通路被认为是膀胱癌治疗干预的候选通路,针对该通路不同成分的抑制剂正处于临床开发的不同阶段。在这里,重点介绍我们对PI3K/AKT/mTOR通路的最新研究进展,并讨论以该通路为靶点的治疗药物作为膀胱癌治疗药物的发展障碍及发展潜力。     

PI3K/AKT/mTOR信号通路介导索拉非尼治疗原发性肝癌耐药机制的研究进展

索拉非尼（sorafenib）作为原发性肝癌（hepatocellular carcinoma,HCC）靶向治疗的一线药物已广泛应用于临床,然而部分HCC患者对索拉非尼治疗耐药导致临床疗效欠佳,联合其他靶向药物的临床实验仍未取得突破,故深入研究索拉非尼耐药机制,逆转索拉非尼耐药对于改善肝癌治疗的预后具有重要意义。最新研究发现,PI3K/AKT/mTOR信号通路在索拉非尼耐药机制中起重要作用,本文将从PI3K/AKT/mTOR信号通路促进肿瘤血管生成、参与细胞自噬、抑制肿瘤细胞凋亡并促进其增殖、与RAS/RAF/ERK/MEK信号通路交联及其促进上皮-间质转化等几个方面,概述其在索拉非尼治疗原发性肝癌时产生耐药的机制,为进一步开发治疗原发性肝癌的新型药物提供研究方向。     

CDO1通过PI3K/AKT信号通路调控胃癌细胞增殖及细胞周期

目的:探讨半胱氨酸双加氧酶1(CDO1)对胃癌细胞增殖、细胞周期的调控机制。方法:用脂质体法将si-NC组（转染si-NC）、si-CDO1组（转染si-CDO1）、pcDNA组（转染pcDNA）、pcDNA-CDO1组（转染pcDNA-CDO1）、pcDNA-CDO1+DMSO组（转染pcDNA-CDO1并用DMSO处理）、pcDNA-CDO1+IGF-1组（转染pcDNA-CDO1并用IGF-1处理）转染至AKG细胞。用实时荧光定量逆转录聚合酶链反应（qRT-PCR）、免疫印迹（Western blot）、细胞计数试剂盒（CCK-8）、流式细胞术检测细胞CDO1、PI3K、Akt、p-Akt蛋白的表达、细胞增殖、细胞周期。结果:与人胃黏膜上皮细胞GES-1相比,胃腺癌细胞AKG中CDO1的表达明显降低（P<0.05）;与si-NC组相比,si-CDO1组AKG细胞的增殖明显上调,细胞发生明显的S期、G2/M期阻滞,过表达CDO1则具有相反的作用。重要的是,敲减CDO1可上调PI3K/AKT信号通路关键基因PI3K、p-Akt的表达,而过表达CDO1具有相反的作用。激活PI3K/AKT信号通路后,过表达CDO1对胃癌细胞的增殖、细胞周期的调控作用可被部分逆转。结论:CDO1可抑制胃癌细胞的增殖,调控细胞周期,其机制与抑制PI3K/AKT信号通路的活性有关,将为胃癌的治疗提供参考。     

Targeting the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway: An emerging treatment strategy for squamous cell lung carcinoma

Squamous cell lung carcinoma accounts for approximately 30% of all non-small cell lung cancers (NSCLCs). Despite progress in the understanding of the biology of cancer, cytotoxic chemotherapy remains the standard of care for patients with squamous cell lung carcinoma, but the prognosis is generally poor. The phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway is one of the most commonly activated signaling pathways in cancer, leading to cell proliferation, survival, and differentiation. It has therefore become a major focus of clinical research. Various alterations in the PI3K/AKT/mTOR pathway have been identified in squamous cell lung carcinoma and a number of agents targeting these alterations are in clinical development for use as single agents and in combination with other targeted and conventional treatments. These include pan-PI3K inhibitors, isoform-specific PI3K inhibitors, AKT inhibitors, mTOR inhibitors, and dual PI3K/mTOR inhibitors. These agents have demonstrated antitumor activity in preclinical models of NSCLC and preliminary clinical evidence is also available for some agents. This review will discuss the role of the PI3K/AKT/mTOR pathway in cancer and how the discovery of genetic alterations in this pathway in patients with squamous cell lung carcinoma can inform the development of targeted therapies for this disease. An overview of ongoing clinical trials investigating PI3K/AKT/mTOR pathway inhibitors in squamous cell lung carcinoma will also be included.     

Bicarbonate transporter SLC4A7 promotes EMT and metastasis of HNSCC by activating the PI3K/AKT/mTOR signaling pathway

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Currently, therapeutic modalities such as surgery, chemotherapy, radiotherapy, and immunotherapy are being used to treat HNSCC. However, the treatment outcomes of most patients are dismal because they are already in middle or advanced stage by the time of diagnosis and poorly responsive to treatments. It is therefore of great interest to clarify mechanisms that contribute to the metastasis of cells to identify possible targets for therapy. In this study, we identified the Na⁺-coupled bicarbonate transporter, SLC4A7, play essential roles in the metastasis of HNSCC. Our results showed that the relative expression of SLC4A7 messenger RNA was highly expressed in HNSCCs samples from TCGA, and compared with precancerous cells of human oral mucosa (DOK), SLC4A7 was highly expressed in HNSCC cell lines. In vitro and in vivo experiments showed that dysregulation of SLC4A7 had minor influence on the proliferation of HNSCC but impacted HNSCC's migration and invasion. Meanwhile, SLC4A7 could promote epithelial-mesenchymal transition (EMT) in HNSCC. RNA-seq, KEGG pathway enrichment analysis and Western blot further revealed that downregulation of SLC4A7 in HNSCC cells inhibited the PI3K/AKT pathway. These findings were further validated via rescue experiments using a small molecule inhibitor of PI3K/mTOR (GDC-0980). Our findings suggest that SLC4A7 promotes EMT and metastasis of HNSCC through the PI3K/AKT/mTOR signaling pathway, which may be a valuable predictive biomarker and potential therapeutic target in HNSCC.     

Multipoint targeting of the PI3K/mTOR pathway in mesothelioma

Background:

Mesothelioma is a notoriously chemotherapy-resistant neoplasm, as is evident in the dismal overall survival for patients with those of asbestos-associated disease. We previously demonstrated co-activation of multiple receptor tyrosine kinases (RTKs), including epidermal growth factor receptor (EGFR), MET, and AXL in mesothelioma cell lines, suggesting that these kinases could serve as novel therapeutic targets. Although clinical trials have not shown activity for EGFR inhibitors in mesothelioma, concurrent inhibition of various activated RTKs has pro-apoptotic and anti-proliferative effects in mesothelioma cell lines. Thus, we hypothesised that a coordinated network of multi-RTK activation contributes to mesothelioma tumorigenesis.

Methods:

Activation of PI3K/AKT/mTOR, Raf/MAPK, and co-activation of RTKs were evaluated in mesotheliomas. Effects of RTK and downstream inhibitors/shRNAs were assessed by measuring mesothelioma cell viability/growth, apoptosis, activation of signalling intermediates, expression of cell-cycle checkpoints, and cell-cycle alterations.

Results:

We demonstrate activation of the PI3K/AKT/p70S6K and RAF/MEK/MAPK pathways in mesothelioma, but not in non-neoplastic mesothelial cells. The AKT activation, but not MAPK activation, was dependent on coordinated activation of RTKs EGFR, MET, and AXL. In addition, PI3K/AKT/mTOR pathway inhibition recapitulated the anti-proliferative effects of concurrent inhibition of EGFR, MET, and AXL. Dual targeting of PI3K/mTOR by BEZ235 or a combination of RAD001 and AKT knockdown had a greater effect on mesothelioma proliferation and viability than inhibition of individual activated RTKs or downstream signalling intermediates. Inhibition of PI3K/AKT was also associated with MDM2-p53 cell-cycle regulation.

Conclusions:

These findings show that PI3K/AKT/mTOR is a crucial survival pathway downstream of multiple activated RTKs in mesothelioma, underscoring that PI3K/mTOR is a compelling target for therapeutic intervention.     

细胞角蛋白13通过PTEN抑制PI3K/AKT/mTOR通路增强鼻咽癌HNE1细胞放疗敏感性

目的:探讨细胞角蛋白13(cytokeratin13,CK13)对鼻咽癌HNE1细胞放疗敏感性的影响及其作用机制.方法:将HNE1细胞分为对照组、anti-CK13#a组及anti-CK13#b组(敲减CK13)、对照组+西罗莫司处理组(100nmol/L的西罗莫司处理1 h)、anti-CK13#a+西罗莫司处理组(...