PI3K/AKT信号通路与心力衰竭

丝氨酸/苏氨酸激酶(serine/threonine kinase,AKT)是真核细胞中参与细胞信号转导的关键分子。目前已经证实PI3K(phosphatidylinositol-3-kinase,PI3K)/AKT信号通路在人类肿瘤、代谢紊乱、肾脏疾病以及精神障碍等疾病中发挥着重要的作用。近年来的研究还发现PI3K/AKT信号通路的激活会对心肌细胞的生长、代谢以及凋亡等活动产生影响,且该通路及其中的很多受体、激酶被证实与心力衰竭关系密切,这使该信号通路在心力衰竭的发病机制、诊断及治疗等方面的研究日益受到重视。总结PI3K/AKT的结构特点、相关信号转导机制及其与心力衰竭的关系将有利于更好地理解心力衰竭的发病机制。     

PI3K/AKT/mTOR信号通路及其在卵巢癌治疗中的应用

卵巢癌是女性生殖系统常见的恶性肿瘤,发病率居于妇科恶性肿瘤第三位,死亡率居于妇科恶性肿瘤之首。目前对卵巢癌的标准治疗包括肿瘤细胞减灭术及卡铂和紫杉醇的联合化疗。PI3K/AKT/mTOR信号通路在卵巢癌的细胞增殖、侵袭、细胞周期进展、血管生成及耐药中发挥重要作用,是卵巢癌中最常发生改变的细胞内途径。本文对PI3K/AKT/mTOR信号通路及其在卵巢癌增殖和进展中的影响、PI3K/AKT/mTOR信号通路抑制剂在卵巢癌中的治疗应用做简要综述。     

Identification of a Role for the PI3K/AKT/mTOR Signaling Pathway in Innate Immune Cells

The innate immune system is the first line of host defense against infection and involves several different cell types. Here we investigated the role of the phosphatidylinositol 3 kinase (PI3K) signaling pathway in innate immune cells. By blocking this pathway with pharmacological inhibitors, we found that the production of proinflammatory cytokines was drastically suppressed in monocytes and macrophages. Further study revealed that the suppression was mainly related to the mammalian target of rapamycin (mTOR)/p70^S6K signaling. In addition, we found that the PI3K pathway was involved in macrophage motility and neovascularization. Our data provide a rationale that inhibition of the PI3K signaling pathway could be an attractive approach for the management of inflammatory disorders.     

PI3K/AKt/mTOR信号通路介导黄芩苷抑制增生性瘢痕组织成纤维细胞的增殖

黄芩苷作为一种黄酮类成分可通过抑制细胞增殖、促进凋亡发挥抗肿瘤作用,但它是否对异常增生的瘢痕具有抑制增生的作用尚不清楚.本研究探讨黄芩苷抑制人增生性瘢痕组织成纤维细胞增殖的分子机制. 采用MTT比色法检测不同浓度的黄芩苷（2.24×10-2 ～ 2.24×102 mmol/L）对体外培养的增生性瘢痕组织成纤维细胞增殖的抑制作用.发现浓度为2.24×100～2.24×102 mmol/L黄芩苷处理组明显抑制增生性瘢痕组织成纤维细胞的增殖（P<0.05）.转染后的荧光素酶报告基因活性检测、RT-PCR及Western印迹分析技术检测其mRNA水平及细胞的帽状依赖翻译的表达.2.24×102 mmol/L黄芩苷处理后,黄芩苷作用组的mRNA水平并无明显差异（P>0.05）;增生性瘢痕成纤维细胞的帽状依赖结构的翻译明显被黄芩苷所抑制.采用Western印迹分析检测被黄芩苷干预的增生性瘢痕组织成纤维细胞的增殖相关的蛋白的表达;m7GTP琼脂糖珠沉淀结合蛋白4E-BP1与eIF4E的变化.发现增殖相关的蛋白mTOR、p70S6K、S6、4EBP1、eIF4E及其上游的AKT表达明显下调（P<0.05）,而PTEN表达明显上调.p-AKT(Ser473)、p-mTOR(Ser2448)、p-S6(Ser235/236)、p-4EBP1(Thr37/ 46)、p-PTEN（T380/S382/383）磷酸化水平下降（P<0.05）.在黄芩苷作用下的增生性成纤维细胞中的游离的4E-BP1明显减少（P<0.05）,而与eIF4E结合的4E-BP1明显增加（P<0.05）黄芩苷诱导游离的4E-BP1与eIF4E结合,从而抑制帽状依赖蛋白翻译.以上结果说明,黄芩苷可通过抑制PI3K/AKT/mTOR信号通路抑制人增生性瘢痕组织成纤维细胞的增殖.     

保护素DX对类风湿关节炎大鼠模型中PI3K/AKT/mTOR信号通路的影响

摘要 目的：研究保护素DX（PDX）对类风湿关节炎（RA）大鼠模型的治疗作用及机制,及其对PI3K/AKT/mTOR信号通路的影响。方法：通过皮下注射牛Ⅱ型胶原与弗氏完全佐剂诱导RA大鼠模型,建模后将SD大鼠随机分为4组：对照组（n=12）：正常SD大鼠;RA组（n=12）：RA模型大鼠;低剂量PDX处理组（n=12,L-PDX组）：接受10 μg/kg/d PDX治疗的RA模型大鼠;高剂量PDX处理组（n=12,H-PDX）：接受20 μg/kg/d PDX治疗的RA模型大鼠。各组大鼠治疗4周后,采用ELISA法检测血清中IgA、IgG、IgM、TNF-α、IFN-γ、IL-4和IL-10的水平。通过苏木精伊红（HE）染色评价大鼠踝关节病变。通过免疫组化染色或Western blot检测滑膜组织中PI3K、p-PI3K、AKT、p-AKT、mTOR、p-mTOR、Bcl-2、Bax、LC3-I、LC3-II和Becline-1的表达。结果：与RA组相比,L-PDX组和H-PDX组的关节炎指数（AI）评分均显著降低（P<0.05）,炎性细胞浸润、软骨破坏程度及滑膜上皮细胞增生减轻。与RA组相比,L-PDX组和H-PDX组的血清IgA、IgG和IgM含量均降低（P<0.05）。与RA组相比,L-PDX组和H-PDX组的血清TNF-α和IFN-γ水平均降低,IL-4和IL-10水平均升高（P<0.05）。与RA组相比,L-PDX组和H-PDX组大鼠踝关节滑膜组织中的p-PI3K/PI3K、p-AKT/AKT、p-mTOR/mTOR和Bcl-2的蛋白相对表达量均降低,而Bax、LC3-II/LC3-I和Becline-1的蛋白相对表达量均升高（P<0.05）。结论：本研究表明PDX可有效减轻RA大鼠症状,其机制与调节B淋巴细胞活化和体液免疫、纠正Th1/Th2失衡、抑制PI3K/Akt/mTOR信号通路有关。     

Silencing of Receptor Tyrosine Kinase ROR1 Inhibits Tumor-Cell Proliferation via PI3K/AKT/mTOR Signaling Pathway in Lung Adenocarcinoma

Receptor tyrosine kinase ROR1, an embryonic protein involved in organogenesis, is expressed in certain hematological malignancies and solid tumors, but is generally absent in adult tissues. This makes the protein an ideal drug target for cancer therapy. In order to assess the suitability of ROR1 as a cell surface antigen for targeted therapy of lung adenocarcinoma, we carried out a comprehensive analysis of ROR1 protein expression in human lung adenocarcinoma tissues and cell lines. Our data show that ROR1 protein is selectively expressed on lung adenocarcinoma cells, but do not support the hypothesis that expression levels of ROR1 are associated with aggressive disease. However silencing of ROR1 via siRNA treatment significantly down-regulates the activity of the PI3K/AKT/mTOR signaling pathway. This is associated with significant apoptosis and anti-proliferation of tumor cells. We found ROR1 protein expressed in lung adenocarcinoma but almost absent in tumor-adjacent tissues of the patients. The finding of ROR1-mediated proliferation signals in both tyrosine kinase inhibitor (TKI)-sensitive and -resistant tumor cells provides encouragement to develop ROR1-directed targeted therapy in lung adenocarcinoma, especially those with TKI resistance.     

The PI3K/AKT Pathway and Renal Cell Carcinoma

The phosphatidylinositol 3 kinase(PI3K)/AKT pathway is genetically targeted in more pathway components and in more tumor types than any other growth factor signaling pathway,and thus is frequently activated as a cancer driver.More importantly,the PI3K/AKT pathway is composed of multiple bifurcating and converging kinase cascades,providing many potential targets for cancer therapy.Renal cell carcinoma(RCC) is a high-risk and high-mortality cancer that is notoriously resistant to traditional chemotherapies or radiotherapies.The PI3K/AKT pathway is modestly mutated but highly activated in RCC,representing a promising drug target.Indeed,PI3 K pathway inhibitors of the rapalog family are approved for use in RCC.Recent large-scale integrated analyses of a large number of patients have provided a molecular basis for RCC,reiterating the critical role of the PI3K/AKT pathway in this cancer.In this review,we summarize the genetic alterations of the PI3K/AKT pathway in RCC as indicated in the latest large-scale genome sequencing data,as well as treatments for RCC that target the aberrant activated PI3K/AKT pathway.     

NEAT1通过PI3K/AKT/Bcl-2信号通路抑制骨质疏松

为探讨NEAT1在骨质疏松症中的作用以及可能的病理机制,本研究通过建立卵巢去势和鼠尾悬挂2种骨质疏松的小鼠模型,将C57BL/6分为假手术组(Sham组)、OVX组和TS组;经过PCR测定小鼠NEAT1的表达;Elisa法检测小鼠E2、ALP和TRACP水平;Western blotting检测细胞凋亡因子PI3K/AKT/Bcl-2的蛋白水平。结果显示,建模4周后,3组小鼠体重没有显著变化;与Sham组相比,OVX组和TS组小鼠的骨密度值显著降低,骨生化指标ALP和TRACR水平明显升高;OVX组小鼠的E2水平与Sham组相比明显降低;与Sham组相比,OVX组和TS组小鼠的NEAT1表达显著下调;与Sham组相比,OVX组和TS组小鼠p-AKT和Bcl-2蛋白水平明显降低。本研究结果表明,NEAT1可能通过抑制PI3K/AKT/Bcl-2细胞凋亡途径诱导骨质疏松。     

Differential Effects of Selective Inhibitors Targeting the PI3K/AKT/mTOR Pathway in Acute Lymphoblastic Leukemia

Purpose

Aberrant PI3K/AKT/mTOR signaling has been linked to oncogenesis and therapy resistance in various malignancies including leukemias. In Philadelphia chromosome (Ph) positive leukemias, activation of PI3K by dysregulated BCR-ABL tyrosine kinase (TK) contributes to the pathogenesis and development of resistance to ABL-TK inhibitors (TKI). The PI3K pathway thus is an attractive therapeutic target in BCR-ABL positive leukemias, but its role in BCR-ABL negative ALL is conjectural. Moreover, the functional contribution of individual components of the PI3K pathway in ALL has not been established.

Experimental Design

We compared the activity of the ATP-competitive pan-PI3K inhibitor NVP-BKM120, the allosteric mTORC1 inhibitor RAD001, the ATP-competitive dual PI3K/mTORC1/C2 inhibitors NVP-BEZ235 and NVP-BGT226 and the combined mTORC1 and mTORC2 inhibitors Torin 1, PP242 and KU-0063794 using long-term cultures of ALL cells (ALL-LTC) from patients with B-precursor ALL that expressed the BCR-ABL or TEL-ABL oncoproteins or were BCR-ABL negative.

Results

Dual PI3K/mTOR inhibitors profoundly inhibited growth and survival of ALL cells irrespective of their genetic subtype and their responsiveness to ABL-TKI. Combined suppression of PI3K, mTORC1 and mTORC2 displayed greater antileukemic activity than selective inhibitors of PI3K, mTORC1 or mTORC1 and mTORC2.

Conclusions

Inhibition of the PI3K/mTOR pathway is a promising therapeutic approach in patients with ALL. Greater antileukemic activity of dual PI3K/mTORC1/C2 inhibitors appears to be due to the redundant function of PI3K and mTOR. Clinical trials examining dual PI3K/mTORC1/C2 inhibitors in patients with B-precursor ALL are warranted, and should not be restricted to particular genetic subtypes.     

Melatonin Enhances Autophagy and Reduces Apoptosis to Promote Locomotor Recovery in Spinal Cord Injury via the PI3K/AKT/mTOR Signaling Pathway

Neurochemical Research - Spinal cord injury (SCI) leads to neuronal death resulting in central nervous system (CNS) dysfunction; however, the pathogenesis is still poorly understood. Melatonin...     

The PI3K/Akt/mTOR Pathway Is Implicated in the Premature Senescence of Primary Human Endothelial Cells Exposed to Chronic Radiation

The etiology of radiation-induced cardiovascular disease (CVD) after chronic exposure to low doses of ionizing radiation is only marginally understood. We have previously shown that a chronic low-dose rate exposure (4.1 mGy/h) causes human umbilical vein endothelial cells (HUVECs) to prematurely senesce. We now show that a dose rate of 2.4 mGy/h is also able to trigger premature senescence in HUVECs, primarily indicated by a loss of growth potential and the appearance of the senescence-associated markers ß-galactosidase (SA-ß-gal) and p21. In contrast, a lower dose rate of 1.4 mGy/h was not sufficient to inhibit cellular growth or increase SA-ß-gal-staining despite an increased expression of p21. We used reverse phase protein arrays and triplex Isotope Coded Protein Labeling with LC-ESI-MS/MS to study the proteomic changes associated with chronic radiation-induced senescence. Both technologies identified inactivation of the PI3K/Akt/mTOR pathway accompanying premature senescence. In addition, expression of proteins involved in cytoskeletal structure and EIF2 signaling was reduced. Age-related diseases such as CVD have been previously associated with increased endothelial cell senescence. We postulate that a similar endothelial aging may contribute to the increased rate of CVD seen in populations chronically exposed to low-dose-rate radiation.     

Deciphering Combinations of PI3K/AKT/mTOR Pathway Drugs Augmenting Anti-Angiogenic Efficacy In Vivo

Ocular neovascularization is a common pathology associated with human eye diseases e.g. age-related macular degeneration and proliferative diabetic retinopathy. Blindness represents one of the most feared disabilities and remains a major burden to health-care systems. Current approaches to treat ocular neovascularisation include laser photocoagulation, photodynamic therapy and anti-VEGF therapies: Ranibizumab (Lucentis) and Aflibercept (Eylea). However, high clinical costs, frequent intraocular injections, and increased risk of infections are challenges related with these standards of care. Thus, there is a clinical need to develop more effective drugs that overcome these challenges. Here, we focus on an alternative approach by quantifying the in vivo anti-angiogenic efficacy of combinations of phosphatidylinositol-3-kinase (PI3K) pathway inhibitors. The PI3K/AKT/mTOR pathway is a complex signalling pathway involved in crucial cellular functions such as cell proliferation, migration and angiogenesis. RT-PCR confirms the expression of PI3K target genes (pik3ca, pik3r1, mtor and akt1) in zebrafish trunks from 6 hours post fertilisation (hpf) and in eyes from 2 days post fertilisation (dpf). Using both the zebrafish intersegmental vessel and hyaloid vessel assays to measure the in vivo anti-angiogenic efficacy of PI3K/Akt/mTOR pathway inhibitors, we identified 5 µM combinations of i) NVP-BEZ235 (dual PI3K-mTOR inhibitor) + PI-103 (dual PI3K-mTOR inhibitor); or ii) LY-294002 (pan-PI3K inhibitor) + NVP-BEZ235; or iii) NVP-BEZ235 + rapamycin (mTOR inhibitor); or iv) LY-294002 + rapamycin as the most anti-angiogenic. Treatment of developing larvae from 2–5 dpf with 5 µM NVP-BEZ235 plus PI-103 resulted in an essentially intact ocular morphology and visual behaviour, whereas other combinations severely disrupted the developing retinal morphology and visual function. In human ARPE19 retinal pigment epithelium cells, however, no significant difference in cell number was observed following treatment with the inhibitor combinations. Collectively, these results highlight the potential of combinations of PI3K/AKT/mTOR pathway inhibitors to safely and effectively treat ocular neovascularization.     

Correlation between Activation of PI3K/AKT/mTOR Pathway and Prognosis of Breast Cancer in Chinese Women

Background

Abnormal activation of PI3K/AKT/mTOR (PAM) pathway, caused by PIK3CA mutation, KRAS mutation, PTEN loss, or AKT1 mutation, is one of the most frequent signaling abnormalities in breast carcinoma. However, distribution and frequencies of mutations in PAM pathway are unclear in breast cancer patients from the mainland of China and the correlation between these mutations and breast cancer outcome remains to be identified.

Methods

A total of 288 patients with invasive ductal breast cancer were recruited in this study. Mutations in PIK3CA (exons 4, 9 and 20), KRAS (exon 2) and AKT1 (exon 3) were detected using Sanger sequencing. PTEN loss was measured by immunohistochemistry assay. Correlations between these genetic aberrations and clinicopathological features were analyzed.

Results

The frequencies of PIK3CA mutation, KRAS mutation, AKT1 mutation and PTEN loss were 15.6%, 1.8%, 4.4% and 35.3%, respectively. However, except for PTEN loss, which was tied to estrogen receptor (ER) status, these alterations were not associated with other clinicopathological features. Survival analysis demonstrated that PIK3CA mutation, PTEN loss and PAM pathway activation were not associated with disease-free survival (DFS). Subgroup analysis of patients with ER positive tumors revealed that PIK3CA mutation more strongly reduced DFS compared to wild-type PIK3CA (76.2% vs. 54.2%; P = 0.011). PIK3CA mutation was also an independent factor for bad prognosis in ER positive patients.

Conclusions

AKT1, KRAS and PIK3CA mutations and PTEN loss all exist in women with breast cancer in the mainland China. PIK3CA mutation may contribute to the poor outcome of ER positive breast carcinomas, providing evidence for the combination of PI3K/AKT/mTOR inhibitors and endocrine therapy.     

间质表皮转化因子通过PI3K/AKT/MMPs信号通路促进肺腺癌细胞的侵袭转移

间质表皮转化因子（mesenchymal to epithelial transition factor,MET）在多种癌症中异常表达,影响肿瘤的发生发展,但MET影响肺腺癌的分子机制并不明确。本研究收集3例淋巴结转移的肺腺癌组织（lung adenocarcinoma tissues,LAD）和3例无淋巴结转移的肺腺癌组织,用于微阵列基因芯片分析。结果显示,与无淋巴结转移的肺腺癌组织相比,有淋巴结转移的肺腺癌组织中有1 314条mRNAs表达上调,400条mRNAs表达下调。其中,MET在有淋巴结转移的肺腺癌组织中表达显著升高。随机选取8个差异表达基因,对收集的潍坊医学院附属医院2014年2月至2017年2月间有淋巴结转移的肺腺癌组织和无淋巴结转移的肺腺癌组织各30例通过qRT -PCR实验进行微阵列基因芯片验证。结果显示,所选mRNAs的表达与微阵列结果一致,验证了微阵列基因芯片结果的准确性。通过Western 印迹进一步检测MET的表达。结果显示,相较于正常肺上皮细胞,肺腺癌细胞中MET的表达显著升高。利用质粒转染,敲减肺腺癌细胞A549中的MET,Transwell侵袭实验结果显示,敲减MET后肺腺癌细胞的侵袭能力明显降低;对各细胞组进行EGF（epidermal growth factor）处理并检测PI3K/AKT/MMPs信号通路,Western 印迹检测结果显示,敲减MET后,肺腺癌细胞中基质金属蛋白酶-2（matrix metalloproteinase 2,MMP-2）和MMP-9的表达显著下降, AKT的磷酸化水平也显著下降。上述结果表明,MET可通过激活PI3K/AKT信号通路进而增加MMPs的表达促进肺腺癌的侵袭转移。     

降糖3号方对肥胖小鼠糖脂代谢及PI3K/AKT信号通路的影响

目的:观察降糖3号方对肥胖模型小鼠的体重、血糖、血清胰岛素含量、糖耐量、血脂等指标的影响,并探讨其对骨骼肌PI3K/AKT信号通路的影响。方法:8周龄C57BL/6J小鼠采用高脂喂养12周的方式诱导肥胖模型,将成模小鼠随机分为模型对照组,二甲双胍组,降糖3号方组,同时以正常饲料喂养的小鼠作为正常对照,进行为期8周的药物干预。每2周测量小鼠的体重、空腹血糖;第7周末进行口服葡萄糖耐量实验。实验结束后进行取材,检测糖化血红蛋白(HbA1c)、胰岛素(Insulin)、总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)水平,免疫印迹法检测骨骼肌组织PI3K、AKT、GLUT4等蛋白的表达。结果:降糖3号方能明显减轻肥胖小鼠的体重(P 0.05);能明显降低肥胖小鼠空腹血糖,使之恢复正常水平(P0.05);降糖3号方组小鼠糖化血红蛋白(HbA1c)、胰岛素(INS)、总胆固醇(TC)、低密度脂蛋白(LDL-C)等指标显著低于模型组(P 0.05),且能有效改善实验动物的糖耐量(P 0.05)。蛋白印迹法检测结果表明,与模型组相比,降糖3号方可上调PI3K、AKT、GLUT4等蛋白表达水平(P 0.05)。结论:降糖3号方能够有效减轻肥胖小鼠体重,改善糖脂代谢,降低胰岛素水平,其作用可能是通过激活PI3K/AKT信号通路来实现。     

Activation of the PI3K/mTOR/AKT Pathway and Survival in Solid Tumors: Systematic Review and Meta-Analysis

Background

Aberrations in the phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR)/AKT pathway are common in solid tumors. Numerous drugs have been developed to target different components of this pathway. However the prognostic value of these aberrations is unclear.

Methods

PubMed was searched for studies evaluating the association between activation of the PI3K/mTOR/AKT pathway (defined as PI3K mutation [PIK3CA], lack of phosphatase and tensin homolog [PTEN] expression by immunohistochemistry or western-blot or increased expression/activation of downstream components of the pathway by immunohistochemistry) with overall survival (OS) in solid tumors. Published data were extracted and computed into odds ratios (OR) for death at 5 years. Data were pooled using the Mantel-Haenszel random-effect model.

Results

Analysis included 17 studies. Activation of the PI3K/mTOR/AKT pathway was associated with significantly worse 5-year survival (OR:2.12, 95% confidence intervals 1.42–3.16, p<0.001). Loss of PTEN expression and increased expression/activation of downstream components were associated with worse survival. No association between PIK3CA mutations and survival was observed. Differences between methods for assessing activation of the PI3K/mTOR/AKT pathway were statistically significant (p = 0.04). There was no difference in the effect of up-regulation of the pathway on survival between different cancer sites (p = 0.13).

Conclusion

Activation of the PI3K/AKT/mTOR pathway, especially if measured by loss of PTEN expression or increased expression/activation of downstream components is associated with poor survival. PIK3CA mutational status is not associated with adverse outcome, challenging its value as a biomarker of patient outcome or as a stratification factor for patients treated with agents acting on the PI3K/AKT/mTOR pathway.     

PI3K/Akt/mTOR信号通路及临床相关肿瘤抑制剂

哺乳动物雷帕霉素靶（mTOR）和蛋白激酶B（Akt/PKB）与肿瘤发生的密切关系已被广泛地认可.mTOR是一种丝/苏氨酸激酶,可以通过影响mRNA转录、代谢、自噬等方式调控细胞的生长.它既是PI3K的效应分子,也可以是PI3K的反馈调控因子.mTORC1 和mTORC2是mTOR的两种不同复合物. 对雷帕霉素敏感的mTORC1受到营养、生长因子、能量和应激4种因素的影响.生长因子通过PI3K/Akt信号通路调控mTORC1是最具特征性调节路径.而mTORC2最为人熟知的是作为Akt473磷酸化位点的上游激酶. 同样,Akt/PKB在细胞增殖分化、迁移生长过程中发挥着重要作用. 随着Thr308和Ser473两个位点激活,Akt/PKB也得以全面活化.因此,mTORC2-Akt-mTORC1的信号通路在肿瘤形成和生长中是可以存在的.目前临床肿瘤治疗中,PI3K/Akt/mTOR是重要的靶向治疗信号通路.然而,仅抑制mTORC1活性,不是所有的肿瘤都能得到预期控制.雷帕霉素虽然能抑制mTORC1,但也能反馈性地增加PI3K信号活跃度,从而影响治疗预后.近来发现的第二代抑制剂可以同时抑制mTORC1/2和PI3K活性,这种抑制剂被认为在肿瘤治疗上颇具前景.本综述着重阐述了PI3K/Akt/mTOR信号通路的传导、各因子之间的相互调控以及相关抑制剂的发展.     

Cytoglobin inhibits migration through PI3K/AKT/mTOR pathway in fibroblast cells

Cell proliferation and migration are crucial in many physiological processes including development, cancer, tissue repair, and wound healing. Cell migration is regulated by several signaling molecules. Identification of genes related to cell migration is required to understand molecular mechanism of non-healing chronic wounds which is a major concern in clinics. In the current study, the role of cytoglobin (CYGB) gene in f?broblast cell migration and proliferation was described. L929 mouse fibroblast cells were transduced with lentiviral particles for CYGB and GFP, and analyzed for cell proliferation and migration ability. Fibroblast cells overexpressing CYGB displayed decreased cell proliferation, colony formation capacity, and cell migration. Phosphorylation levels of mTOR and two downstream effectors S6 and 4E-BP1 which take part in PI3K/AKT/mTOR signaling declined in CYGB-overexpressing cells. Microarray analysis indicated that CYGB overexpression leads to downregulation of cell proliferation, migration, and tumor growth associated genes in L929 cell line. This study demonstrated the role of CYGB in fibroblast cell motility and proliferation. CYGB could be a promising candidate for further studies as a potential target for diseases related to cell migration such as cancer and chronic wound treatment.     

The PI3K/AKT/mTOR signaling pathway inhibitors enhance radiosensitivity in cancer cell lines

Molecular Biology Reports - Malignant tumors have become the most dangerous disease in recent years. Chemotherapy is the most effective treatment for this disease; however, the problem of drug...