抑癌基因PTEN、PI3K、AKT在肺癌中的表达及临床意义

目的：探讨抑癌基因PTEN、PI3K、AKT在肺癌中的表达及临床病理学意义研究。方法采用免疫组化SP法检测PTEN、PI3K和AKT蛋白在62例肺癌组织和30例癌旁肺组织中的表达情况,并分析两者的相关性及与临床病理特征的关系,探讨其在肺癌中的作用机制。结果 PTEN mRNA在肺癌组织中表达明显低于癌旁组织,但PI3K mRNA和AKT mRNA在肺癌组织中表达则高于癌旁组织,差异均有统计学意义（P＜0．05）。 PTEN在肺癌组织中的阳性表达率为48．39％（30/62）,明显低于癌旁组织,而PI3K和AKT在肺癌组织中的阳性表达率分别为79．03％（49/62）和70．97％（44/62）,明显高于癌旁组织,差异具有统计学意义（ P＜0．01）。 PTEN、PI3K表达与肺癌的分化程度、TNM分期、淋巴结转移及病理类型相关,而AKT表达与肺癌的TNM分期、淋巴结转移及病理类型相关（ P＜0．05）。 PI3K与AKT表达呈正相关（P＜0．05）,与PTEN表达呈负相关（P＜0．05）,AKT与PTEN表达呈负相关（P＜0．05）。结论抑癌基因PTEN在肺癌中的低表达和PI3K/AKT的高表达,提示了PTEN、PI3K及AKT可能促进了肺癌的发生、发展及转移,而PI3 K/AKT细胞信号通路在此过程中起重要作用,可为肺癌的基因靶向治疗提供一个新的方向。     

PI3K/PTEN/AKT/mTOR pathway genetic variation predicts toxicity and distant progression in lung cancer patients receiving platinum-based chemotherapy

Non-small cell lung cancer (NSCLC) is still the leading cause of cancer-related deaths. The effect of the PI3K/PTEN/AKT/mTOR signaling pathway on cancer treatment, including NSCLC, has been well documented. In this study, we analyzed associations between genetic variations within this pathway and clinical outcomes following platinum-based chemotherapy in 168 patients with stage IIIB (wet) or stage IV NSCLC. Sixteen tagging SNPs in five core genes (PIK3CA, PTEN, AKT1, AKT2, and FRAP1) of this pathway and identified SNPs associated with development of toxicity and disease progression. We observed significantly increased toxicity for patients with PIK3CA:rs2699887 (OR: 3.86, 95% CI: 1.08-13.82). In contrast, a SNP in PTEN was associated with significantly reduced risk for chemotherapeutic toxicity (OR: 0.44, 95% CI: 0.20-0.95). We identified three SNPs in AKT1 resulting in significantly decreased risks of distant progression in patients carrying at least one variant allele with HRs of 0.66 (95% CI: 0.45-0.97), 0.52 (95% CI: 0.35-0.77), and 0.62 (95% CI: 0.42-0.91) for rs3803304, rs2498804, and rs1130214, respectively. Furthermore, these same variants conferred nearly 2-fold increased progression-free survival times. The current study provides evidence that genetic variations within the PI3K/PTEN/AKT/mTOR signaling pathway are associated with variation in clinical outcomes of NSCLC patients. With further validation, our findings may provide additional biomarkers for customized treatment of platinum-based chemotherapy for NSCLC.     

miR-103 靶向PTEN并激活PI3K/AKT通路促进肺癌细胞A549 对达沙替尼耐药

[摘要] 目的：探讨miR-103 靶向PTEN并激活PI3K/AKT信号通路促进肺癌细胞对达沙替尼（dasatinib,DASA）耐药的机制。方法：收集2014 年4 月至2018 年1 月昆明医科大学第一附属医院胸外科收治的资料完整的肺癌DASA耐药组织和不耐药组织各35 例。采用qPCR实验检测miR-103 在肺癌DASA耐药组织和细胞中的表达水平,同时,采用CCK-8、Transwell 和Wb实验检测敲降miR-103 对A549/DASA细胞增殖、迁移和上皮间质转化（EMT）的影响,双荧光素酶报告基因验证miR-103 与PTEN的靶向关系。进一步采用CCK-8、Transwell 和Wb实验检测miR-103 通过PTEN-PI3K/AKT信号通路对A549/DASA细胞恶性生物学行为的影响。结果：miR-103 在肺癌DASA 耐药组织和A549/DASA 细胞中均高表达（均P<0.01）。敲降miR-103 可显著抑制A549/DASA细胞的增殖、迁移和EMT（P<0.05 或P<0.01）。此外,双荧光素酶报告基因证实miR-103 靶向作用PTEN并下调其表达水平（P<0.01）。进一步实验显示,过表达miR-103 通过靶向下调PTEN并激活PI3K/AKT信号通路进而显著促进A549/DASA细胞增殖、迁移和EMT（P<0.05 或P<0.01）,从而上调A549/DASA细胞对DASA的耐药性。结论：miR-103/PTEN/PI3K/AKT信号通路与肺癌DASA耐药性存在调控关系,敲降miR-103 可逆转A549/DASA对DASA耐药。     

PI3K/AKT信号通路相关蛋白在乳腺癌中的表达及其临床意义

目的：研究PI3K/AKT信号转导通路中PTEN、PI3K、AKT蛋白在乳腺癌中的表达及其与疾病发生发展、预后的关系。方法用免疫组化SP法检测45例乳腺癌患者病理组织（观察组）和其中15例患者癌旁正常组织（对照组）中PTEN、PI3K、AKT表达情况,采用单因素回归分析对PTEN、PI3K、AKT蛋白在乳腺癌组织中阳性表达的相关因素进行分析。结果 PI3K、AKT在乳腺癌中的表达率分别为73.3%、75.5%,高于癌旁正常乳腺组织的33.3%、40%,差异具有统计学意义（P﹤0.05）;PTEN在乳腺癌中表达率为22.2%,低于癌旁正常乳腺组织的53.3%,但差异无统计学意义（P﹥0.05）;单因素回归分析结果显示,患者发病年龄对PTEN、PI3K、AKT在乳腺癌组织中阳性表达无关（P﹥0.05）;组织学分级、临床分期、存在淋巴结转移是PTEN、PI3K、AKT在乳腺癌组织中的阳性表达的相关因素（P﹤0.05）。结论 PI3K/AKT信号通路可能参与了乳腺癌的发生与发展,PTEN蛋白表达缺失导致AKT、PI3K蛋白的过度表达,PI3K、PTEN、AKT蛋白表达的检测可能有助于预测乳腺癌的预后。     

吉西他滨对肺癌细胞凋亡及PI3K/AKT信号通路的影响

目的探讨吉西他滨对肺癌细胞凋亡及PI3K/AKT信号通路的影响。方法选取对数生长期的肺癌NCI-H292细胞随机分为吉西他滨组、阿霉素组和对照组,分别采用7μmol/L的吉西他滨、阿霉素与生理盐水处理,采用CCK-8法检测细胞增殖,Transwell小室检测细胞迁移与侵袭,Annexin V-PI双标记法检测细胞凋亡,Western blot实验检测PI3K和AKT蛋白表达。结果细胞处理后24h和48h,吉西他滨组和阿霉素组的细胞增殖指数均低于对照组,吉西他滨组低于阿霉素组,差异均有统计学意义(均P <0.05)。细胞处理后24h和48h,吉西他滨组和阿霉素组的细胞迁移与侵袭指数均低于对照组,吉西他滨组低于阿霉素组,差异均有统计学意义(均P <0.05)。细胞处理后24h和48h,吉西他滨组和阿霉素组的细胞凋亡指数均高于对照组,吉西他滨组高于阿霉素组,差异均有统计学意义(均P <0.05)。细胞处理后24h和48h,吉西他滨组和阿霉素组PI3K和AKT蛋白表达水平均低于对照组,吉西他滨组低于阿霉素组,差异均有统计学意义(均P <0.05)。结论吉西他滨可促进肺癌...     

PI3K/AKT通路在肺癌转移和耐药中的研究

磷脂酰肌醇-3-激酶/丝苏氨酸蛋白激酶(phosphatidyl-inositol 3-kinase/serine-threonine kinase,PI3K/AKT)信号通路是细胞内重要信号转导通路之一,通过影响下游多种效应分子的活化状态,在细胞内发挥抑制凋亡、促进增殖的关键作用,与人类多种肿瘤的发生发展密切相关。研究表明PI3K/AKT信号通路在恶性肿瘤细胞的增殖、血管新生和转移及对放化疗的拮抗中都起着重要作用。对PI3K/AKT信号通路的深入研究有望找到肿瘤预防和药物治疗的新靶点。本文简要介绍了PI3K/AKT信号通路的组成与功能调节,并着重阐述了其在肺癌转移和耐药中的作用。     

Overexpression of FYN suppresses the epithelial-to-mesenchymal transition through down-regulating PI3K/AKT pathway in lung adenocarcinoma

BackgroundTyrosine-protein kinase Fyn (FYN) plays a crucial role in Src family, which participates in the signal transduction of brain nerves and the development and activation of T lymphocytes in physiological conditions. We probed into the roles and mechanisms of FYN in lung adenocarcinoma (LUAD).MethodsCell activity, apoptosis, invasion, and migration were detected by CCK-8, FCM, transwell, and wound-healing assays, respectively. The angiogenesis capacity was evaluated by in vitro angiogenesis test. Relative mRNA and protein expressions were determined by qRT-PCR, Western blot, and immunohistochemistry assays, respectively. Insulin-like growth factors-I (IGF-I) was used as an agonist of PI3K/AKT pathway.ResultsWe demonstrated that FYN expression correlated with LUAD prognosis and was down-regulated in LUAD tissues and LUAD cells. Overexpression of FYN suppressed the cell viability, together with invasion and migration abilities of A549 cells. FYN overexpression accelerated the cell apoptosis and reduced the angiogenesis capacity of A549 cells. Overexpression of FYN suppressed E-cadherin, Vimentin, Snail, and PI3K/AKT expressions in A549 cells. High expression level of FYN reduced the migration and invasion capacities of A549 cells via down-regulating the PI3K/AKT pathway.ConclusionCollectively, our findings reveal that overexpression of FYN inhibits the epithelial-to-mesenchymal transition (EMT) through down-regulating the PI3K/AKT pathway in A549 cells.     

miR-429通过下调PTEN并激活PI3K/AKT信号通路促进胰腺癌PANC-1细胞对卡培他滨耐药

目的:探讨miR-429 靶向PTEN并通过PI3K/AKT信号通路调控胰腺癌PANC-1 细胞对卡培他滨的耐药性及其作用机制。方法：建立胰腺癌卡培他滨耐药细胞株PANC-1/CAP后,采用qRT-PCR和Western blotting 实验检测miR-429 和PTEN在胰腺癌细胞中的表达情况,平板克隆形成实验、CCK-8 法和Annexin V-FITC/PI 双染流式细胞术检测敲降miR-429 对胰腺癌卡培他滨耐药细胞株PANC-1/CAP 细胞增殖、凋亡和卡培他滨耐药性的影响,双荧光素酶报告基因验证miR-429 与PTEN 的靶向关系,Western blotting 实验进一步检测miR-429 对PTEN-PI3K/AKT信号通路的调控作用。结果：miR-429 在胰腺癌PANC-1 细胞和PANC-1/CAP细胞中的表达水平高于人胰腺导管上皮细胞（HPDE6-C7）（P<0.05 或P<0.01）,敲降miR-429 可显著抑制PANC-1/CAP细胞增殖活力、促进细胞凋亡及下调细胞卡培他滨耐药性,且双荧光素酶报告基因证实miR-429 靶向作用PTEN并下调其表达水平（P<0.05 或P<0.01）;敲降miR-429 可通过靶向上调PTEN并阻断PI3K/AKT信号通路进而显著抑制PANC-1/CAP细胞增殖活力,从而下调PANC-1/CAP细胞对卡培他滨的耐药性（P<0.05 或P<0.01）。结论：miR-429/PTEN-PI3K、AKT信号通路与胰腺癌卡培他滨耐药性存在调控关系,且敲降miR-429 可逆转PANC-1/CAP对卡培他滨的耐药性。     

PI3K/AKT pathway activation in bladder carcinogenesis

The PI3K/AKT pathway is considered to play a major role in bladder carcinogenesis, but its relationships with other molecular alterations observed in bladder cancer remain unknown. We investigated PI3K/AKT pathway activation in a series of human bladder urothelial carcinomas (UC) according to PTEN expression, PTEN deletions and FGFR3, PIK3CA, KRAS, HRAS, NRAS and TP53 gene mutations. The series included 6 normal bladder urothelial samples and 129 UC (Ta n = 25, T1 n = 34, T2–T3–T4 n = 70). Expression of phospho‐AKT (pAKT), phospho‐S6‐Ribosomal Protein (pS6) (one downstream effector of PI3K/AKT pathway) and PTEN was evaluated by reverse phase protein Array. Expression of miR‐21, miR‐19a and miR‐222, known to regulate PTEN expression, was also evaluated. pAKT expression levels were higher in tumors than in normal urothelium (p < 0.01), regardless of stage and showed a weak and positive correlation with pS6 (Spearman coefficient R_S = 0.26; p = 0.002). No association was observed between pAKT or pS6 expression and the gene mutations studied. PTEN expression was decreased in PTEN‐deleted tumors, and in T1 (p = 0.0089) and T2–T3–T4 (p < 0.001) tumors compared to Ta tumors; it was also negatively correlated with miR‐19a (R_S = ?0.50; p = 0.0088) and miR‐222 (R_S = ?0.48; p = 0.0132), but not miR‐21 (R_S = ?0.27; p = 0.18) expression. pAKT and PTEN expressions were not negatively correlated, and, on the opposite, a positive and moderate correlation was observed in Ta (R_S = 0.54; p = 0.0056) and T1 (R_S = 0.56; p = 0.0006) tumors. Our study suggests that PI3K/AKT pathway activation occurs in the entire spectrum of bladder UC regardless of stage or known most frequent molecular alterations, and independently of low PTEN expression.     

非小细胞肺癌大分割放疗敏感性与PI3K/AKT/mTOR信号通路研究进展

常规分割放疗在中晚期非小细胞肺癌治疗中疗效有限,大分割放疗地位越来越重要,但仍有相当部分肿瘤细胞具有放射线抗拒,其分子机制未明。PI3K/AKT/mTOR信号通路与非小细胞肺癌常规分割放疗抗拒有关,但与大分割放疗抗拒关系尚未明确。调控PI3K/AKT/mTOR信号通路的基因表达及蛋白磷酸化水平有望增加NSCLC肿瘤细胞对大分割放疗的敏感性,并可能达到逆转放疗抗拒的效果;在PI3K/AKT/mTOR信号通路的诸多基因中,有望从临床样本中筛选获得预测NSCLC大分割放疗疗效的分子标记。      

Genetic modelling of the PTEN/AKT pathway in cancer research

The focus on targeted therapies has been fuelled by extensive research on molecular pathways and their role in tumorigenesis. Novel models of human cancer have been created to evaluate the role of specific genes in the different stages of cancer. Currently, mouse modelling of human cancer is possible through the expression of oncogenes, specific genetic mutations or the inactivation of tumour suppressor genes, and these models have begun to provide us with an understanding of the molecular pathways involved in tumour initiation and progression at the physiological level. Additionally, these mouse models serve as an excellent system to evaluate the efficacy of currently developed molecular targeted therapies and identify new potential targets for future therapies. The PTEN/AKT pathway is implicated in signal transduction through tyrosine kinase receptors and heterotrimeric G protein-linked receptors. Deregulation of the PTEN/AKT pathway is a common event in human cancer. Despite the abundant literature, the physiological role of each element of the pathway has begun to be uncovered thanks to genetically engineered mice. This review will summarise some of the key animal models which have helped us to understand this signalling network and its contribution to tumorigenesis. Supported by an unrestricted educational grant from Pfizer.     

Genetic variants in the PI3K/PTEN/AKT/mTOR pathway predict platinum-based chemotherapy response of advanced non-small cell lung cancers in a Chinese population

Objective: The PI3K/PTEN/AKT/mTOR signaling pathway has been implicated in resistance to cisplatin.In the current study, we determined whether common genetic variations in this pathway are associated withplatinum-based chemotherapy response and clinical outcome in advanced non-small cell lung cancer (NSCLC)patients. Methods: Seven common single nucleotide polymorphisms (SNPs) in core genes of this pathway weregenotyped in 199 patients and analyzed for associations with chemotherapy response, progression-free survival(PFS) and overall survival (OS). Results: Logistic regression analysis revealed an association between AKT1rs2494752 and response to treatment. Patients carrying heterozygous AG had an increased risk of diseaseprogression after two cycles of platinum-based chemotherapy compared to those with AA genotype (Adjustedodds ratio (OR)=2.18, 95% confidence interval (CI): 1.00-4.77, which remained significant in the stratifiedanalyses). However, log-rank test and cox regression detected no association between these polymorphisms inthe PI3K pathway genes and survival in advanced NSCLC patients. Conclusions: Our findings suggest thatgenetic variants in the PI3K/PTEN/AKT/mTOR pathway may predict platinum-based chemotherapy responsein advanced NSCLC patients in a Chinese population.     

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(...     

Suppression of esophageal tumor growth and chemoresistance by directly targeting the PI3K/AKT pathway

Esophageal cancer is the sixth most common cause of cancer-related deaths worldwide. Novel therapeutic intervention is urgently needed for this deadly disease. The functional role of PI3K/AKT pathway in esophageal cancer is little known. In this study, our results from 49 pairs of human esophageal tumor and normal specimens demonstrated that AKT was constitutively active in the majority (75.5%) of esophageal tumors compared with corresponding normal tissues. Inhibition of the PI3K/AKT pathway with specific inhibitors, wortmannin and {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002, significantly reduced Bcl-xL expression, induced caspase-3-dependent apoptosis, and repressed cell proliferation and tumor growth in vitro and in vivo without obvious toxic effects. Moreover, significantly higher expression level of p-AKT was observed in fluorouracil (5-FU)-resistant esophageal cancer cells. Inactivation of PI3K/AKT pathway markedly increased the sensitivity and even reversed acquired resistance of esophageal cancer cells to chemotherapeutic drugs in vitro. More importantly, the resistance of tumor xenografts derived from esophageal cancer cells with acquired 5-FU resistance to chemotherapeutic drugs was significantly abrogated by wortmannin treatment in animals. In summary, our data support PI3K/AKT as a valid therapeutic target and strongly suggest that PI3K/AKT inhibitors used in conjunction with conventional chemotherapy may be a potentially useful therapeutic strategy in treating esophageal cancer patients.     

PFKFB3通过调控PI3K/AKT信号通路促进骨肉瘤细胞的增殖及转移

目的:探讨6-磷酸果糖2-激酶/果糖-2,6-二磷酸酶3(6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3,PFKFB3)对骨肉瘤细胞增殖、凋亡、迁移及侵袭的影响,及可能的作用机制.方法:采用实时荧光定量PCR法、蛋白质印迹法及免疫组织化学法检测骨肉瘤组织及其相...     

PI3K、AKT、PTEN在脑胶质瘤中的表达及其临床意义

背景与目的：PI3K/AKT信号通路可能在人脑恶性胶质瘤的发生发展过程中起重要作用。本研究探讨人脑胶质瘤中PI3K/AKT通路相关蛋白PI3K、AKT、PTEN在脑胶质瘤中的表达及其与胶质瘤病理分级之间的关系。方法：采用免疫组化Envision二步法检测PI3K、AKT、PTEN蛋白在42例不同级别脑胶质瘤、10例正常脑组织中的表达,计算阳性细胞百分率,用统计学方法分析人脑胶质瘤中PI3K、AKT、PTEN蛋白表达之间的相关性及其三者与胶质瘤不同分级之间的关系。结果：PI3K在人脑胶质瘤组织的阳性表达率是80.95%,而正常脑组织中表达率为20.00%,两者间差异有统计学意义（P〈0.05）;PI3K蛋白在低级别胶质瘤和高级别胶质瘤中的阳性率分别是66.67%、95.24%,两者之间差异有统计学意义（P〈0.05）。胶质瘤组织与正常脑组织中AKT蛋白阳性率分别是85.71%与30.00%,两者差异有统计学意义（P〈0.05）;AKT蛋白在低级别胶质瘤和高级别胶质瘤中的阳性率分别是76.19%与95.24%,两者之间差异有统计学意义（P〈0.05）;胶质瘤组织与正常脑组织中PTEN蛋白阳性率分别是45.24%、100%,两者差异有统计学意义（P〈0.01）;PTEN蛋白在低级别胶质瘤中的阳性率52.38%,而高级别胶质瘤表达率为38.10%,两者之间差异有显著性（P〈0.05）;PTEN与PI3K、AKT蛋白在脑胶质瘤中的表达分别呈负相关（P〈0.01）;PI3K与AKT蛋白的阳性表达呈正相关（P〈0.01）。结论：（1）在人脑胶质瘤组织中PI3K、AKT蛋白表达明显增高,且PI3K、AKT蛋白阳性表达与胶质瘤恶性程度正相关,说明了PI3K/AKT信号通路在胶质瘤的恶性转化中发挥着重要作用。（2）胶质瘤组织中PTEN蛋白的阳性表达率明显低于其在正常脑组织中的表达,与胶质瘤的恶性程度负相关,提示了PTEN蛋白的表达下降或缺失导致其抑癌功能减弱甚至丧失,其与胶质瘤的发生发展密切相关。（3）在人脑胶质瘤组织中,PTEN与PI3K、AKT蛋白表达呈负相关,揭示了在胶质瘤的发生发展中PTEN与PI3K、AKT的作用可能互相拮抗,PTEN蛋白的表达下降或缺失与PI3K、AKT的过度表达可能共同促进了胶质瘤的恶性进展。     

白花丹醌通过CXCL8/PI3K/AKT糖酵解通路抑制结肠癌细胞增殖、促进凋亡

目的:观察白花丹醌对结肠癌细胞Caco-2增殖、凋亡的影响,探究其潜在的作用机制。方法:运用CCK8法、流式细胞术检测不同浓度白花丹醌（4、8、12 μmol/L）处理的Caco-2细胞的增殖抑制率、凋亡率。不做任何处理的Caco-2细胞设为Control;脂质体法将si-NC组（转染si-NC）、si-CXCL8组（转染si-CXCL8）转染至Caco-2细胞;8 μmol/L的白花丹醌与0.5%DMSO处理的Caco-2细胞设为8 μmol/L+DMSO组;8 μmol/L的白花丹醌分别与z-VAD-FMK、740Y-P处理的Caco-2细胞设为8 μmol/L+z-VAD-FMK组、8 μmol/L+740Y-P组。RT-qPCR、Western blot实验检测细胞中CXCL8的mRNA、蛋白表达,CXCL8、M2-型丙酮酸激酶（M2 pyruvate kinase, PKM2）、L-乳酸脱氢酶A（lactate dehydrogenase A,LDHA）、人α-烯醇化酶(apha-enolase,ENO1)、葡萄糖磷酸异构酶（glucose phosphate isomerase,GPI）、磷酸化磷脂酰肌醇3激酶（phosphorylated phosphatidylinositol 3 kinase,p-PI3K）、磷酸化蛋白激酶B（phosphorylated protein kinase B,p-AKT）的蛋白表达。结果:与Control组相比,白花丹醌（4、8、12 μmol/L）呈浓度依赖性促进Caco-2细胞增殖抑制率、凋亡率升高,抑制CXCL8的mRNA和蛋白表达。与8 μmol/L+DMSO组相比,8 μmol/L+z-VAD-FMK组细胞的增殖抑制率、凋亡率明显降低,CXCL8的mRNA和蛋白表达明显升高（P＜0.05）。白花丹醌（4、8、12 μmol/L）呈浓度依赖性抑制PKM2、LDHA、p-PI3K、p-AKT的蛋白表达。si-CXCL8组PKM2、LDHA、p-PI3K、p-AKT的蛋白表达明显低于si-NC组。740Y-P明显减弱白花丹醌对Caco-2细胞增殖抑制率和凋亡率的促进作用。结论:白花丹醌抑制结肠癌细胞增殖,促进凋亡,其潜在的作用机制与CXCL8/PI3K/AKT糖酵解通路有关。     

淫羊藿素通过PI3K/AKT信号通路抑制非小细胞肺癌H460细胞增殖

目的:探讨淫羊藿素（icaritin）通过PI3K/AKT信号通路对非小细胞肺癌H460细胞增殖的影响。方法:采用MTT比色实验检测,不同浓度（0、5、10、20、40、80μmol/L）淫羊藿素处理H460细胞24、48、72h后细胞增殖抑制率,流式细胞仪检测不同浓度淫羊藿素对H460细胞凋亡的影响,Western blot实验检测不同浓度淫羊藿素对H460细胞中PI3K、AKT、p-AKT、Cleaved-Caspase-9蛋白质表达水平的影响。结果:淫羊藿素可抑制非小细胞肺癌H460细胞的增殖,并表现为剂量和时间依赖性（P＜0.05）。0、5、10、20μmol/L淫羊藿素处理H460细胞24h后,H460细胞凋亡率分别为（4.90±1.20）%、（13.5±2.32）%、（16.47±1.90）%和（27.43±3.15）%,P＜0.05。淫羊藿素可下调PI3K、AKT的表达水平,降低AKT的磷酸化(p-AKT)水平,上调Cleaved-Caspase-9表达水平(P＜0.05)。结论:淫羊藿素可能通过抑制PI3K/AKT信号通路激活,抑制H460细胞增殖。     

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。     

Frequent genetic and biochemical alterations of the PI 3-K/AKT/PTEN pathway in head and neck squamous cell carcinoma

We investigated the status of the PI 3-kinase/AKT/PTEN signaling pathway in a series of 117 head and neck squamous cell carcinomas (HNSCC) in a search for molecular alterations in genes/proteins with potential prognostic value. For this purpose, PIK3CA and AKT2 gene amplification was assessed by multiplex and Quantitative Real-Time PCR. Protein expression of AKT, p-AKT, p110alpha and PTEN was determined by Western blot. PTEN allelic loss was evaluated by microsatellite analysis. PTEN-exon 5 was screened for point mutations by PCR-SSCP. Homozygous deletions were determined by multiplex PCR. PIK3CA gene was amplified in 43/117 (37%) fresh tumor samples, a frequency that did not differ from that found in archival premalignant tissues: 15/38 (39%); 12/40 (30%) fresh tumors harbored AKT2 gene amplification. AKT was found activated in 6/36 (17%) fresh tumor samples, when compared to their normal tissue counterparts. Of these 6 cases, 1 showed p110alpha overexpression and 5 displayed PTEN protein downregulation. Neither allelic loss (found in 11/77 informative cases) nor point mutations or homozygous deletions accounted for the reduced PTEN protein expression observed in our tumor series. The histologically normal mucosa of 4 patients displayed some of the molecular alterations analyzed. Dysregulation of the PI 3-K/AKT/PTEN pathway might contribute to early HNSCC tumorigenesis and might constitute a potential clinical target. Overall, 17/36 (47%) cases showed at least 1 of the molecular alterations studied here, which makes the PI 3-kinase-initiated signaling pathway one of the most frequently altered in HNSCC.