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Expression of AKT and p-AKT protein in lung adenocarcinoma and its correlation with PD-L1 protein and prognosis. Hu Zhi-Ying,Huang Wan-Yi,Zhang Lei,Huang Bo,Chen Shu-Chen,Li Xiao-Ling Annals of translational medicine Background:The PI3K/AKT/mTOR signaling pathway were significantly associated with EGFR mutation in lung adenocarcinoma (LUAD), but its correlation with PD-L1 protein and prognosis are not clear. The aim of this study was to evaluate the expression of AKT and phosphorylated AKT (p-AKT) in LUAD and its correlation with programmed death ligand-1 (PD-L1); and to analyze the factors affecting LUAD prognosis. Methods:The expression of AKT, p-AKT, and PD-L1 was examined using immunohistochemistry in LUAD tissues from 110 patients who underwent surgical treatment. Results:AKT protein expression was examined in 64.5% (71/110) of the LUAD samples, and p-AKT protein expression was examined in 44.5% (49/110) of the LUAD samples. The positive rate of PD-L1 at TC1/2/3 was 38.2% (42/110). AKT and p-AKT expression was significantly associated with epidermal growth factor receptor (EGFR) mutation (P=0.016, P=0.014 respectively). Pearson's correlation analysis indicated a negative correlation of p-AKT with PD-L1 protein (P=0.022). Out of the 62 patients with EGFR mutation, the expression of PD-L1 was negatively correlated with that of p-AKT protein (P=0.032). The expressions of AKT and p-AKT were not associated with prognosis. Multivariate analysis showed that tumor-node-metastasis (TNM) stage (P=0.013) and differentiation (P=0.046) were independent prognostic factors for overall survival. Conclusions:PI3K/AKT/mTOR in the downstream pathway of EGFR may negatively regulate the expression of PD-L1, which may partly explain why patients with EGFR mutation respond poorly to PD-1/PD-L1 inhibitors. 10.21037/atm-20-5865
Prognostic Role of the Activated p-AKT Molecule in Various Hematologic Malignancies and Solid Tumors: A Meta-Analysis. Yao Zhen,Gao Guangyu,Yang Jiawen,Long Yuming,Wang Zhenzhen,Hu Wentao,Liu Yulong Frontiers in oncology Cancer is one of the main causes of human death worldwide. Recently, many studies have firmly established the causal relationship between oxidative stress and cancer initiation and progression. As a key protein in PI3K/Akt signaling pathway, p-AKT (phosphorylated Akt) participates in the process of oxidative stress and plays a prognostic role in various hematologic tumors and solid tumors. We conducted a comprehensive search of the PubMed, Embase and Cochrane libraries to identify studies published in the past decade involving cancer patients expressing p-AKT that reported overall survival (OS) during follow-up. In this study, 6,128 patients in total were evaluated from 29 enrolled articles, and we concluded that overexpression of p-AKT was closely related to worse OS in cancer patients with a hazard ratio (HR) of 2.33 (95% CI: 1.67-4.00). Furthermore, we conducted a subgroup analysis, and the results indicated that overexpression of p-AKT was associated with worse OS in hematological tumor (HR: 1.64, 95% CI: 1.41-1.92), and solid tumor (HR: 2.44, 95% CI: 1.61-5.26). High expression of p-AKT is related to poor prognosis of various hematologic tumors and solid tumors. 10.3389/fonc.2020.588200
Combined inhibition of MEK and PI3K pathways overcomes acquired resistance to EGFR-TKIs in non-small cell lung cancer. Sato Hiroki,Yamamoto Hiromasa,Sakaguchi Masakiyo,Shien Kazuhiko,Tomida Shuta,Shien Tadahiko,Ikeda Hirokuni,Hatono Minami,Torigoe Hidejiro,Namba Kei,Yoshioka Takahiro,Kurihara Eisuke,Ogoshi Yusuke,Takahashi Yuta,Soh Junichi,Toyooka Shinichi Cancer science Compensatory activation of the signal transduction pathways is one of the major obstacles for the targeted therapy of non-small cell lung cancer (NSCLC). Herein, we present the therapeutic strategy of combined targeted therapy against the MEK and phosphoinositide-3 kinase (PI3K) pathways for acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in NSCLC. We investigated the efficacy of combined trametinib plus taselisib therapy using experimentally established EGFR-TKI-resistant NSCLC cell lines. The results showed that the feedback loop between MEK/ERK and PI3K/AKT pathways had developed in several resistant cell lines, which caused the resistance to single-agent treatment with either inhibitor alone. Meanwhile, the combined therapy successfully regulated the compensatory activation of the key intracellular signals and synergistically inhibited the cell growth of those cells in vitro and in vivo. The resistance mechanisms for which the dual kinase inhibitor therapy proved effective included (MET) mesenchymal-epithelial transition factor amplification, induction of epithelial-to-mesenchymal transition (EMT) and EGFR T790M mutation. In further analysis, the combination therapy induced the phosphorylation of p38 MAPK signaling, leading to the activation of apoptosis cascade. Additionally, long-term treatment with the combination therapy induced the conversion from EMT to mesenchymal-to-epithelial transition in the resistant cell line harboring EMT features, restoring the sensitivity to EGFR-TKI. In conclusion, our results indicate that the combined therapy using MEK and PI3K inhibitors is a potent therapeutic strategy for NSCLC with the acquired resistance to EGFR-TKIs. 10.1111/cas.13763
Adenovirus vector infection of non-small-cell lung cancer cells is a trigger for multi-drug resistance mediated by P-glycoprotein. Tomono Takumi,Kajita Masahiro,Yano Kentaro,Ogihara Takuo Biochemical and biophysical research communications P-glycoprotein (P-gp) is an ATP-binding cassette protein involved in cancer multi-drug resistance (MDR). It has been reported that infection with some bacteria and viruses induces changes in the activities of various drug-metabolizing enzymes and transporters, including P-gp. Although human adenoviruses (Ad) cause the common cold, the effect of Ad infection on MDR in cancer has not been established. In this study, we investigated whether Ad infection is a cause of MDR in A549, H441 and HCC827 non-small-cell lung cancer (NSCLC) cell lines, using an Ad vector system. We found that Ad vector infection of NSCLC cell lines induced P-gp mRNA expression, and the extent of induction was dependent on the number of Ad vector virus particles and the infection time. Heat-treated Ad vector, which is not infectious, did not alter P-gp mRNA expression. Uptake experiments with doxorubicin (DOX), a P-gp substrate, revealed that DOX accumulation was significantly decreased in Ad vector-infected A549 cells. The decrease of DOX uptake was blocked by verapamil, a P-gp inhibitor. Our results indicated that Ad vector infection of NSCLC cells caused MDR mediated by P-gp overexpression. The Ad vector genome sequence is similar to that of human Ad, and therefore human Ad infection of lung cancer patients may lead to chemoresistance in the clinical environment. 10.1016/j.bbrc.2016.05.070
Screening common signaling pathways associated with drug resistance in non-small cell lung cancer via gene expression profile analysis. Sun Ting,Zhao Qitai,Zhang Chaoqi,Cao Ling,Song Mengjia,Maimela Nomathamsanqa Resegofetse,Liu Shasha,Wang Jinjin,Gao Qun,Qin Guohui,Wang Liping,Zhang Yi Cancer medicine Lung cancer is the leading cause of cancer-related deaths worldwide. Although several therapeutic strategies have been employed to curb lung cancer, the survival rate is still poor owing to the development of drug resistance. The mechanisms underlying drug resistance development are incompletely understood. Here, we aimed to identify the common signaling pathways involved in drug resistance in non-small cell lung cancer (NSCLC). Three published transcriptome microarray data were downloaded from the Gene Expression Omnibus (GEO) database comprising different drug-resistant cell lines and their parental cell lines. Differentially expressed genes (DEGs) were identified and used to perform Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. An overlapping analysis was performed for KEGG pathways enriched from all the three datasets to identify the common signaling pathways. As a result, we found that metabolic pathways, ubiquitin-mediated proteolysis, and mitogen-activated protein kinase (MAPK) signaling were the most aberrantly expressed signaling pathways. The knockdown of nicotinamide phosphoribosyltransferase (NAMPT), the gene involved in metabolic pathways and known to be upregulated in drug-resistant tumor cells, was shown to increase the apoptosis of cisplatin-resistant A549 cells following cisplatin treatment. Thus, our results provide an in-depth analysis of the signaling pathways that are commonly altered in drug-resistant NSCLC cell lines and highlight the potential strategy that facilitates the development of interventions to interfere with upregulated signaling pathways as well as to boost downregulated signaling pathways in drug-resistant tumors for the elimination of multiple resistance of NSCLC. 10.1002/cam4.2190