β-Eudesmol Inhibits the Migration of Cholangiocarcinoma Cells by Suppressing Epithelial-Mesenchymal Transition via PI3K/AKT and p38MAPK Modulation

Background: Cholangiocarcinoma (CCA) is a highly aggressive tumor with a greater risk of distant metastasis. A drug that prevents CCA development and spread is urgently needed.  In this research, we investigated the effect of β-eudesmol on the migration and invasion and epithelial-mesenchymal transformation (EMT) of the CCA cell line. Materials and Methods: MTT and transwell assays were used to investigate the antiproliferative activity, as well as activity on cell migration and cell invasion. Real-time PCR and western blot analysis were used to investigate the expression of EMT marker genes and proteins. Results: β-eudesmol was shown to exhibit potent antiproliferative activity (IC50 92.25-185.67 µM) and to significantly reduce CCA cell migration and invasion (27.3-62.7%). At both mRNA and protein levels, it significantly up-regulated the expression of epithelial marker E-cadherin (3-3.4-fold), while down-regulated the expression of mesenchymal markers-vimentin (0.6-0.8-fold) and snail-1 (0.4-0.6-fold). Furthermore, β-eudesmol inhibited PI3K and AKT phosphorylation (0.5-0.8-fold), while activating p38MAPK activity (1.2-3.6-fold). Conclusion: Altogether, the anti-metastatic activity of β-eudesmol might be due to its suppressive effect on EMT via modulating the PI3K/AKT and p38MAPK signaling cascades.     

Prognostic and predictive role of the PI3K–AKT–mTOR pathway in neuroendocrine neoplasms

Neuroendocrine neoplasms (NENs) are considered a heterogeneous and rare entity. Its natural history is influenced by multiple clinicopathological characteristics, which guide the management of these patients. The development of molecular biology reveals that the PI3K–AKT–mTOR pathway plays a relevant role in tumorigenesis and progression of NENs. Mammalian target of rapamycin (mTOR) inhibitors, targeted agents that block this pathway, has improved outcomes in neuroendocrine tumors (NETs). Different therapeutic approaches, such as somatostatin analogs, chemotherapy, peptide receptor radionuclide therapy, and targeted agents, have shown benefits in the treatment of NETs. However, there are not any established prognostic or predictive biomarkers to select the best therapy option to individualize treatment. Although a relation between alterations in the PI3K–AKT–mTOR pathway and clinical outcomes has not been found, these anomalies are considered attractive biomarkers. Additional molecular analysis should be integrated in future clinical trials’ design to identify potential predictive or prognostic biomarkers.     

A novel small molecule antagonist of choline kinase-α that simultaneously suppresses MAPK and PI3K/AKT signaling

Choline kinase-α expression and activity are increased in multiple human neoplasms as a result of growth factor stimulation and activation of cancer-related signaling pathways. The product of choline kinase-α, phosphocholine, serves as an essential metabolic reservoir for the production of phosphatidylcholine, the major phospholipid constituent of membranes and substrate for the production of lipid second messengers. Using in silico screening for small molecules that may interact with the choline kinase-α substrate binding domain, we identified a novel competitive inhibitor, N-(3,5-dimethylphenyl)-2-[[5-(4-ethylphenyl)-1H-1,2,4-triazol-3-yl]sulfanyl] acetamide (termed CK37) that inhibited purified recombinant human choline kinase-α activity, reduced the steady-state concentration of phosphocholine in transformed cells, and selectively suppressed the growth of neoplastic cells relative to normal epithelial cells. Choline kinase-α activity is required for the downstream production of phosphatidic acid, a promoter of several Ras signaling pathways. CK37 suppressed mitogen-activated protein kinase and phosphatidylinositol 3-kinase/AKT signaling, disrupted actin cytoskeletal organization, and reduced plasma membrane ruffling. Finally, administration of CK37 significantly decreased tumor growth in a lung tumor xenograft mouse model, suppressed tumor phosphocholine, and diminished activating phosphorylations of extracellular signal-regulated kinase and AKT in vivo. Together, these results further validate choline kinase-α as a molecular target for the development of agents that interrupt Ras signaling pathways, and indicate that receptor-based computational screening should facilitate the identification of new classes of choline kinase-α inhibitors.     

Simultaneous Inhibition of PI3Kδ and PI3Kα Induces ABC-DLBCL Regression by Blocking BCR-Dependent and -Independent Activation of NF-κB and AKT

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鼻咽癌细胞PI3K/AKT和ERK/MAPK信号通路活性表达及其临床意义的探讨

目的:探讨鼻咽癌细胞中PK3K/AKT和ERK/MAPK信号传导通路异常激活与鼻咽癌细胞发生发展的关系.方法:蛋白质印迹法检测3例鼻咽低分化鳞癌组织及其细胞株(CNE2)和鼻咽炎性组织中IGF-1R、AKT和ERKl/2蛋白的表达情况;相同实验方法检测鼻咽癌细胞株CNE2中磷酸化的PAKT和pERK1/2蛋白的表达和给予胰岛素样生长因子-1(IGF-1)刺激癌细胞后磷酸化的pAKT和pERK的表达水平,再分别用PKB/AKT和ERK/MAPK通路抑制剂对CNE2细胞信号传导通路磷酸化的调节作用进行抑制试验.结果:3例鼻咽低分化鳞癌组织和cNE2细胞株中IGF-1R、AKT和ERK1/2蛋白表达水平明显高于鼻咽炎性组织;IGF-1可刺激CNE2细胞中PAKT和pERK1/2的表达增加,与空白对照组相比,其pAKT和pERK表达量明显增高;给予wortrnannin和PD98059治疗24和48 h后,CNE2细胞株生长明显受到抑制.结论:IGF-lR的过度表达及其PK3K/AKT、ERK/MAPK信号传导通路的异常激活在鼻咽癌的发生、发展过程中可能起着非常重要的作用,IGF-1R系统有可能作为复发或转移性鼻咽癌治疗中一个潜在的靶分子.中华肿瘤防治杂志.2009,16(1):44-47     

AnnexinA5 promote glioma cell invasion and migration via the PI3K/Akt/NF-κB signaling pathway

Malignant glioma (MG), the most common primary brain tumor in adults, is extremely aggressive and uniformly fatal. Several treatment strategies have shown significant preclinical promise in murine models of glioma; however, none have produced meaningful clinical responses in human patients. We hypothesize that introduction of an additional preclinical animal model better approximating the complexity of human MG, particularly in interactions with host immune responses, will bridge the existing gap between these two stages of testing. Here, we characterize the immunologic landscape and gene expression profiles of spontaneous canine glioma and evaluate its potential for serving as such a translational model. RNA in situ hybridization, flowcytometry, and RNA sequencing were used to evaluate immune cell presence and gene expression in healthy and glioma-bearing canines. Similar to human MGs, canine gliomas demonstrated increased intratumoral immune cell infiltration (CD4+, CD8+ and CD4+Foxp3+ T cells). The peripheral blood of glioma-bearing dogs also contained a relatively greater proportion of CD4+Foxp3+ regulatory T cells and plasmacytoid dendritic cells. Tumors were strongly positive for PD-L1 expression and glioma-bearing animals also possessed a greater proportion of immune cells expressing the immune checkpoint receptors CTLA-4 and PD-1. Analysis of differentially expressed genes in our canine populations revealed several genetic changes paralleling those known to occur in human disease. Naturally occurring canine glioma has many characteristics closely resembling human disease, particularly with respect to genetic dysregulation and host immune responses to tumors, supporting its use as a translational model in the preclinical testing of prospective anti-glioma therapies proven successful in murine studies.     

EBV-BZLF1通过激活PI3K/AKT信号通路促进胃癌细胞生长

  目的   明确EB病毒（Epstein-Barr virus,EBV）BZLF1基因（EBV-BZLF1）对EB病毒阴性胃癌细胞生物学行为的影响及可能的分子机制。   方法   运用过表达BZLF1的慢病毒感染胃癌细胞系AGS和HGC27,分别采用CCK8、细胞凋亡检测、细胞迁移和侵袭实验及Western blot法检测细胞的增殖能力、细胞凋亡与迁移侵袭能力及细胞信号通路变化情况。将过表达BZLF1的胃癌细胞HGC27注射于非肥胖糖尿病/重症联合免疫缺陷（NOD/SCID）小鼠背部皮下构建移植瘤模型,观察BZLF1对肿瘤生长的影响。   结果   过表达BZLF1的慢病毒感染组AGS-BZLF1与HGC27-BZLF1相比亲本细胞,细胞中BZLF1蛋白表达明显上调;体外细胞增殖与小鼠体内成瘤能力均显著增强（P < 0.05）;细胞凋亡受到BZLF1蛋白的抑制,其中AGS-BZLF1和HGC27-BZLF1凋亡率为（2.40± 0.14）%和（3.90±0.14）%,显著低于AGS和HGC细胞的（5.75±0.35）%和（9.70±0.42）%（P < 0.05）;但细胞迁移和侵袭能力无明显改变。深入分子机制研究发现,BZLF1表达上调后,PI3K/AKT信号通路明显激活,表现为pAKT和pS6蛋白表达上调。使用BEZ235抑制剂阻断PI3K/AKT信号通路后,HGC27-BZLF1和AGS-BZLF1细胞的生长均受到抑制。   结论   EBV-BZLF1可通过激活PI3K/ AKT信号通路促进胃癌细胞生长,靶向PI3K/AKT通路抑制剂或可成为EBV阳性胃癌的治疗选择。      

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。     

Overcoming hypoxia-induced apoptotic resistance through combinatorial inhibition of GSK-3β and CDK1

Tumor hypoxia is an inherent impediment to cancer treatment that is both clinically significant and problematic. In this study, we conducted a cell-based screen to identify small molecules that could reverse the apoptotic resistance of hypoxic cancer cells. Among the compounds, we identified were a structurally related group that sensitized hypoxic cancer cells to apoptosis by inhibiting the kinases GSK-3β and cyclin-dependent kinase (CDK) 1. Combinatorial inhibition of these proteins in hypoxic cancer cells and tumors increased levels of c-Myc and decreased expression of c-IAP2 and the central hypoxia response regulator hypoxia-inducible factor (HIF) 1α. In mice, these compounds augmented the hypoxic tumor cell death induced by cytotoxic chemotherapy, blocking angiogenesis and tumor growth. Taken together, our findings suggest that combinatorial inhibition of GSK-3β and CDK1 augment the apoptotic sensitivity of hypoxic tumors, and they offer preclinical validation of a novel and readily translatable strategy to improve cancer therapy.     

Notch1 promotes glioma cell migration and invasion by stimulating β-catenin and NF-κB signaling via AKT activation

The Notch signaling pathway has been implicated in both developmental processes and tumorigenesis. Aberrant Notch signaling has been repeatedly demonstrated to facilitate the proliferation and survival of glioma cells by regulating downstream effectors or other signaling pathways. In glioblastoma multiforme specimens from 59 patients, Notch1 was highly expressed in tumor tissues compared with normal brain tissues, and this expression was correlated with elevated AKT phosphorylation and Snail expression. Increased nuclear localization of β-catenin and p50 as well as enhanced IKKα/AKT interaction were also observed in glioma tissues. In U87MG cells, the activation of Notch1 by DLL4 stimulation or by the overexpression of Notch intracellular domain (NICD) resulted in AKT activation and thereby promoted β-catenin activity and NF-κB signaling. Inhibition of EGFR partially blocked the β-catenin and NF-κB signaling stimulated by Notch1 activation. Furthermore, NICD overexpression in U87MG cells led to the upregulated expression of several metastasis-associated molecules, which could be abrogated by the knockdown of either β-catenin or p50. In U87MG and U251 cells, DLL4-induced cellular migration and invasion could be inhibited by either β-catenin or a p50 inhibitor. Collectively, these results indicate that Notch activation could stimulate β-catenin and NF-κB signaling through AKT activation in glioma cells. Thus, Notch activation-stimulated β-catenin and NF-κB signaling synergistically promote the migratory and invasive properties of glioma cells.     

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.