scholarly journals Upregulation of Long Noncoding RNA_GAS5 Suppresses Cell Proliferation and Metastasis in Laryngeal Cancer via Regulating PI3K/AKT/mTOR Signaling Pathway

2021 ◽  
Vol 20 ◽  
pp. 153303382199007
Author(s):  
Wenlin Liu ◽  
Jiandong Zhan ◽  
Rong Zhong ◽  
Rui Li ◽  
Xiaoli Sheng ◽  
...  

Background: Laryngeal cancer is one of the most common malignant tumors among head and neck cancers. Accumulating studies have indicated that long noncoding RNAs (lncRNAs) play an important role in laryngeal cancer occurrence and progression, however, the functional roles and relative regulatory mechanisms of lncRNA growth arrest-specific transcript 5 (GAS5) in laryngeal cancer progression remain unclear. Methods: The expression of lncRNA GAS5 in both laryngeal cancer tissues and cell lines was evaluated using quantitative reverse transcription-polymerase chain reaction (RT-qPCR) assay. The relationships between lncRNA GAS5 expression and clinical parameters were also analyzed. To determine the biological function of lncRNA GAS5, a lncRNA GAS5-specific plasmid was first transfected into laryngeal cancer cells using lentiviral technology. Cell counting kit-8 assay, flow cytometry, and Transwell assays were used to detect in vitro cell proliferation, apoptosis, cycle distribution, and metastasis abilities, respectively. Furthermore, in vivo cell growth experiments were also performed using nude mice. Additionally, western blotting was performed to identify the underlying regulatory mechanism. Results: In the current study, lncRNA GAS5 was downregulated in laryngeal cancer tissues and its low expression was closely associated with poor tumor differentiation, advanced TNM stage, lymph node metastasis, and shorter overall survival time. In addition, lncRNA GAS5 upregulation significantly inhibited laryngeal cancer cell proliferation both in vitro and in vivo. Moreover, in response to lncRNA GAS5 overexpression, more laryngeal cancer cells were arrested at the G2/M stage, accompanied by increased cell apoptosis rates and suppressed migration and invasion capacities. Mechanistically, our data showed that the overexpression of lncRNA GAS5 significantly regulated the PI3K/AKT/mTOR signaling pathway. Conclusion: LncRNA GAS5 might act as a suppressor gene during laryngeal cancer development, as it suppressed cell proliferation and metastasis by regulating the PI3K/AKT/mTOR signaling pathway; thus, lncRNA GAS5 is a promising therapeutic biomarker for the treatment of laryngeal cancer.

2020 ◽  
Author(s):  
Jian Li ◽  
Danli Ye ◽  
Peng Shen ◽  
Xiaorong Liu ◽  
Peirong Zhou ◽  
...  

Abstract Background: The X-linked gene WTX (also called AMER1) has been reported to function as a tumour suppressor gene in Wilms’ tumour. In our previous study, WTX expression was shown to be significantly reduced in gastric cancer (GC), but the function and mechanism associated with WTX loss had yet to be fully elucidated. Methods: WTX expression and clinical significance were father analyzed in GC and control normal gastric tissues, and validated in public databases. The candidate pathway which was regulated by WTX during GC progression was searched by KEGG pathway analysis. The miRNA which monitored WTX expression was screened by miRNA microarray. After verified the pathway and miRNA both in vitro and in vivo, the relationship of miRNA, WTX and the downstream pathway were analyzed by Western blot, immunohistochemistry, RT-PCR, Co-immunoprecipitation (Co-IP), and luciferase analyses.Results: The results showed that WTX serves as a tumour suppressor gene in GC. The loss of WTX which is associated with the aggressiveness of GC by promoting GC cell proliferation in vitro and high metastasis in vivo. Furthermore, WTX expression was positively correlated with the overall survival of GC patients. Microarray assays, bioinformatics analysis, and verification experiments showed that WTX loss activates the PI3K/AKT/mTOR pathway and promotes GC cell proliferation and invasion. And the aberrant miR-20a-5p upregulation contributes to WTX loss in GC, which stimulates PI3K phosphorylation to activate PI3K/AKT/mTOR signaling pathway and promoted GC progression.Conclusions: The results of the present study elucidated the mechanism of GC progression, which is at least partially caused by aberrant miR-20a-5p upregulation leading to the inhibition of WTX expression and PI3K/AKT/mTOR signaling pathway activation. These findings provide a comprehensive understanding of the action of the miR-20a-5p/WTX/PI3K/AKT/mTOR signaling pathway in the progression and metastasis of GC.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Hong-Bo Li ◽  
Jun-Kai Chen ◽  
Ze-Xin Su ◽  
Qing-Lin Jin ◽  
Li-Wen Deng ◽  
...  

Abstract Background Osteosarcoma is the most common primary bone tumor in children and adolescents. However, some patients with osteosarcoma develop resistance to chemotherapy, leading to a poor clinical prognosis. Hence, effective therapeutic agents that can improve the response to chemotherapy drugs to improve the prognosis of patients with osteosarcoma are urgently needed. Cordycepin has recently emerged as a promising antitumor drug candidate. This study aims to explore the effect of cordycepin in suppressing osteosarcoma in vivo and in vitro and the synergistic effect of cordycepin combined with cisplatin and to demonstrate the underlying molecular mechanism. Methods CCK-8 assay was performed to investigate the inhibition effect of cordycepin combined with cisplatin in osteosarcoma cell lines. The colony formation and invasion abilities were measured by colony formation assay and Transwell assay. Osteosarcoma cells apoptosis was detected by flow cytometry. Western blot analysis were used to detect the expression of cell apoptosis-related proteins and AMPK and AKT/mTOR signaling pathway-related proteins. Finally, we performed the in vivo animal model to further explore whether cordycepin and cisplatin exert synergistic antitumor effects. Results Notably, we found that treatment with cordycepin inhibited cell proliferation, invasion, and induced apoptosis in osteosarcoma cells in vitro and in vivo. Moreover, the combination of cordycepin and cisplatin led to marked inhibition of osteosarcoma cell proliferation and invasion and promoted osteosarcoma cell apoptosis in vitro and in vivo. Mechanistically, we demonstrated that cordycepin enhanced the sensitivity of osteosarcoma cells to cisplatin by activating AMPK and inhibiting the AKT/mTOR signaling pathway. Conclusions In brief, this study provides comprehensive evidence that cordycepin inhibits osteosarcoma cell growth and invasion and induces osteosarcoma cell apoptosis by activating AMPK and inhibiting the AKT/mTOR signaling pathway and enhances the sensitivity of osteosarcoma cells to cisplatin, suggesting that cordycepin is a promising treatment for osteosarcoma.


Author(s):  
Jian Li ◽  
Danli Ye ◽  
Peng Shen ◽  
Xiaorong Liu ◽  
Peirong Zhou ◽  
...  

Abstract Background The X-linked gene WTX (also called AMER1) has been reported to function as a tumour suppressor gene in Wilms’ tumour. In our previous study, WTX expression was shown to be significantly reduced in gastric cancer (GC), but the function and mechanism associated with WTX loss had yet to be fully elucidated. Methods WTX expression and clinical significance were father analyzed in GC and control normal gastric tissues, and validated in public databases. The candidate pathway which was regulated by WTX during GC progression was searched by KEGG pathway analysis. The miRNA which monitored WTX expression was screened by miRNA microarray. After verified the pathway and miRNA both in vitro and in vivo, the relationship of miRNA, WTX and the downstream pathway were analyzed by Western blot, immunohistochemistry, RT-PCR, Co-immunoprecipitation (Co-IP), and luciferase analyses. Results The results showed that WTX serves as a tumour suppressor gene in GC. The loss of WTX which is associated with the aggressiveness of GC by promoting GC cell proliferation in vitro and high metastasis in vivo. Furthermore, WTX expression was positively correlated with the overall survival of GC patients. Microarray assays, bioinformatics analysis, and verification experiments showed that WTX loss activates the PI3K/AKT/mTOR pathway and promotes GC cell proliferation and invasion. And the aberrant miR-20a-5p upregulation contributes to WTX loss in GC, which stimulates PI3K phosphorylation to activate PI3K/AKT/mTOR signaling pathway and promoted GC progression. Conclusions The results of the present study elucidated the mechanism of GC progression, which is at least partially caused by aberrant miR-20a-5p upregulation leading to the inhibition of WTX expression and PI3K/AKT/mTOR signaling pathway activation. These findings provide a comprehensive understanding of the action of the miR-20a-5p/WTX/PI3K/AKT/mTOR signaling pathway in the progression and metastasis of GC.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Zhenjian Xu ◽  
Junzhe Chen ◽  
Anping Xu

Abstract Background and Aims Our previous study found a new regulatory T cell subpopulation, CD4+CD126lowFoxp3+ regulatory T cells (CD4+CD126lowFoxp3+ Treg). This cell can maintain a stable immune regulatory function in the inflammatory state. Through in vivo and in vitro experiments, we have confirmed that CD4+CD126lowFoxp3+ Treg has an immunotherapeutic effect on T cell-mediated mouse models of autoimmune diseases such as colitis and collagen-induced arthritis (CIA). Further experimental studies showed that CD4+CD126lowFoxp3+ Treg could reduce the kidney injury caused by autoantibodies and prolong the survival time of lupus mice. However, the mechanism of CD4+CD126lowFoxp3+ Treg immunotherapy in lupus nephritis is not clear. The purpose of this study was to explore the mechanism of CD4+CD126lowFoxp3+ Treg immunotherapy in mice with lupus nephritis. Method In vitro experiments CD4+CD126lowFoxp3+ Treg or CD4+CD126lowFoxp3+ Treg pretreated with PD-1 inhibitor were co-cultured with T or B lymphocytes of lupus mice under different in vitro culture condition. The expression levels of Akt and mTOR of Treg in each group were measured under immunoinflammatory conditions. To observe the effects and differences of Treg groups on the activation, proliferation and differentiation of T or B cells and other immunomodulatory effects. In vivo experiments CD4+CD126lowFoxp3+ Treg (2 × 106/mouse) and CD4+CD126lowFoxp3+ Treg (2 × 106/mouse) pretreated with PD-1 inhibitor and PBS were injected into NZM2328 lupus mice, respectively. After cell injection, urine protein was measured weekly. Autoantibody expression in lupus mice was measured every two weeks. The effects of Treg on the proliferation and differentiation of T/B cells in lupus mice were observed. The therapeutic effects of Treg on lupus mice were observed. Results Compared with CD4+CD126lowFoxp3+ Treg, the expression of Akt and mTOR increases in PD-1 inhibitors pretreatment cells. The activation, proliferation and differentiation functions of T or B lymphocytes of lupus mice were significantly weakened by immunosuppression of PD-1 inhibitors pretreated Treg in vitro, indicating that CD4+CD126lowFoxp3+ Treg may inhibit Akt-mTOR signaling pathway through PD-1 in in vitro. Compared with CD4+CD126lowFoxp3+ Treg, the activation, proliferation and differentiation functions of T or B lymphocytes of lupus mice were significantly weakened by immunosuppression of PD-1 inhibitors pretreated Treg in vivo. And its therapeutic effect on lupus mice was ineffective, indicating that CD4+CD126lowFoxp3+ Treg may inhibit Akt-MTOR signaling pathway through PD-1 in vivo. Conclusion CD4+CD126lowFoxp3+ Treg may inhibit the Akt-mTOR signaling pathway by expressing PD-1, and maintain stable immunomodulatory function in the inflammatory state, thus producing immunotherapeutic effect on lupus nephritis mice.


Marine Drugs ◽  
2018 ◽  
Vol 16 (9) ◽  
pp. 325 ◽  
Author(s):  
Xiaojuan Li ◽  
Yunping Tang ◽  
Fangmiao Yu ◽  
Yu Sun ◽  
Fangfang Huang ◽  
...  

We investigated the antitumor mechanism of Anthopleura anjunae oligopeptide (AAP-H, YVPGP) in prostate cancer DU-145 cells in vitro and in vivo. Results indicated that AAP-H was nontoxic and exhibited antitumor activities. Cell cycle analysis indicated that AAP-H may arrest DU-145 cells in the S phase. The role of the phosphatidylinositol 3-kinase/protein kinase B/mammalian rapamycin target protein (PI3K/AKT/mTOR) signaling pathway in the antitumor mechanism of APP-H was investigated. Results showed that AAP-H treatment led to dose-dependent reduction in the levels of p-AKT (Ser473), p-PI3K (p85), and p-mTOR (Ser2448), whereas t-AKT and t-PI3K levels remained unaltered compared to the untreated DU-145 cells. Inhibition of PI3K/AKT/mTOR signaling pathway in the DU-145 cells by employing inhibitor LY294002 (10 μM) or rapamycin (20 nM) effectively attenuated AAP-H-induced phosphorylation of AKT and mTOR. At the same time, inhibitor addition further elevated AAP-H-induced cleaved-caspase-3 levels. Furthermore, the effect of AAP-H on tumor growth and the role of the PI3K/AKT/mTOR signaling pathway in nude mouse model were also investigated. Immunohistochemical analysis showed that activated AKT, PI3K, and mTOR levels were reduced in DU-145 xenografts. Western blotting showed that AAP-H treatment resulted in dose-dependent reduction in p-AKT (Ser473), p-PI3K (p85), and p-mTOR (Ser2448) levels, whereas t-AKT and t-PI3K levels remained unaltered. Similarly, Bcl-xL levels decreased, whereas that of Bax increased after AAP-H treatment. AAP-H also increased initiator (caspase 8 and 9) and executor caspase (caspase 3 and 7) levels. Therefore, the antitumor mechanism of APP-H on DU-145 cells may involve regulation of the PI3K/AKT/mTOR signaling pathway, which eventually promotes apoptosis via mitochondrial and death receptor pathways. Thus, the hydrophobic oligopeptide (YVPGP) can be developed as an adjuvant for the prevention or treatment of prostate cancer in the future.


Author(s):  
Zhao-Ming Xiao ◽  
Dao-Jun Lv ◽  
Yu-zhong Yu ◽  
Chong Wang ◽  
Tao Xie ◽  
...  

BackgroundSWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin subfamily C member 1 (SMARCC1) protein is a potential tumor suppressor in various cancers. However, its role in prostate cancer (PCa) remains controversial. The aim of this study was to determine the biological function of SMARCC1 in PCa and explore the underlying regulatory mechanisms.MethodsThe expression of SMARCC1 was validated in PCa tissues by immunohistochemistry. Meanwhile, function experiments were used to evaluate the regulatory role on cell proliferation and metastasis in PCa cells with SMARCC1 depletion both in vitro and in vivo. The expression levels of relevant proteins were detected by Western blotting.ResultsOur finding showed that SMARCC1 was significantly downregulated in prostate adenocarcinoma, with a higher Gleason score (GS) than that in low GS. The decreased expression of SMARCC1 was significantly correlated with a higher GS and poor prognosis. Additionally, we found that silencing of SMARCC1 dramatically accelerated cell proliferation by promoting cell cycle progression and enhancing cell migration by inducing epithelial mesenchymal transition (EMT). Furthermore, depletion of SMARCC1 facilitated PCa xenograft growth and lung metastasis in murine models. Mechanistically, the loss of SMARCC1 activated the PI3K/AKT pathway in PCa cells.ConclusionSMARCC1 suppresses PCa cell proliferation and metastasis via the PI3K/AKT signaling pathway and is a novel therapeutic target.


2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Guangtao Han ◽  
Yubiao Zhang ◽  
Haohuan Li

Osteoarthritis (OA) is a chronic joint disease characterized by cholesterol accumulation in chondrocytes, cartilage degeneration, as well as extracellular matrix (ECM) destruction, and joint dysfunction. Curcumin, a chemical that can reduce cholesterol levels in OA patients, also can inhibit the progression of OA. However, a high concentration of curcumin may also trigger apoptosis in normal chondrocytes. Besides curcumin, probucol that is found can also effectively decrease the cholesterol level in OA patients. Considering that high cholesterol is a risk factor of OA, it is speculated that the combination treatment of curcumin and probucol may be effective in the prevention of OA. To investigate the possible effects of such two chemicals on OA pathophysiology, chondrocyte apoptosis and autophagy behavior under inflammatory cytokine stress were studied, and specifically, the PI3K-Akt-mTOR signaling pathway was studied. Methods. Cell proliferation, colony formation, and EdU assay were performed to identify the cytotoxicity of curcumin and probucol on chondrocytes. Transwell assay was conducted to evaluate chondrocyte migration under TNF-α inflammation stress. Immunofluorescence, JC-1, flow cytometry, RT-PCR, and western blot were used to investigate the signal variations related to autophagy and apoptosis in chondrocytes and cartilage. A histological study was carried out on OA cartilage. Glycosaminoglycan (GAG) release was determined to evaluate the ECM degradation under stress. Results. Compared with a single intervention with curcumin or probucol, a combined treatment of these two chemicals is more effective in terms of protecting chondrocytes from stress injury induced by inflammatory cytokines. The promoted protection may be attributed to the inhibition of apoptosis and the blockage of the autophagy-related PI3K/Akt/mTOR pathway. Such results were also verified in vitro by immunofluorescence staining of OA chondrocytes and in vivo by immunohistochemistry staining of cartilage. Besides, in vivo studies also showed that when applied in combination, curcumin and probucol could block the PI3K-AKT-mTOR signaling pathway; promote COL-II expression; suppress P62, MMP-3, and MMP-13 expression; and inhibit TNF-α-stimulated cartilage degradation. Moreover, the combined medication could help reduce the release of ECM GAGs in OA cartilage and alleviate the severity of OA. Conclusion. A combined treatment of curcumin and probucol could be used to protect chondrocytes from inflammatory cytokine stress via inhibition of the autophagy-related PI3K/Akt/mTOR pathway both in vitro and in vivo, which might be of potential pharmaceutical value for OA prevention and therapy.


Author(s):  
Dan Wei ◽  
Shaofei Wu ◽  
Jie Liu ◽  
Xiaoqian Zhang ◽  
Xiaoling Guan ◽  
...  

Theobromine, a methylxanthine present in cocoa, has been shown to possess many beneficial pharmacological properties such as anti-oxidative stress, anti-inflammatory property, and anti-microbial activity. In this study, we investigated the effects of theobromine on NAFLD and the possible underlying mechanisms in vivo and in vitro. The results showed that theobromine reduced body weight, fat mass and improved dyslipidemia. Theobromine decreased liver weight, mitigated liver injury, and significantly reduced hepatic TG level in mice with obesity. Histological examinations also showed hepatic steatosis was alleviated after theobromine treatment. Furthermore, theobromine reversed the elevated mRNA and protein expression of SREBP-1c, FASN, CD36, FABP4 and the suppressed expression of PPARα, CPT1a in the liver of mice with obesity, which were responsible for lipogenesis, fatty acid uptake and fatty acid oxidation respectively. In vitro, theobromine also downregulated SREBP-1c, FASN, CD36, FABP4 and upregulated PPARα, CPT1a mRNA and protein levels in hepatocytes in a dose-dependent manner, while these changes were reversed by L-Leucine, an mTOR agonist. The present study demonstrated that theobromine improved NAFLD by inhibiting lipogenesis, fatty acid uptake and promoting fatty acid oxidation in the liver and hepatocytes, which might be associated with its suppression of mTOR signaling pathway.


2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Jianwen Long ◽  
Xianming Pi

To investigate whether Polyphyllin I (PPI) might induce the autophagy and apoptosis of melanoma cells by regulating PI3K/Akt/mTOR signal pathway. Melanoma A375 cells were incubated with different concentrations of Polyphyllin I (0, 1.5, 3.0, and 6.0 mg/L) and PI3K/Akt/mTOR signaling pathway activator IGF-1(20 mg/L). CCK-8 assay was utilized to detect cell proliferation; Cell apoptosis and cell cycle were measured by flow cytometry; Western blot was used to examine the expressions of proteins. Immunofluorescence analysis was performed to evaluate autophagy of A375 cells; In addition, xenograft-bearing nude mice were applied to study the role of Polyphyllin I on melanoma development, melanoma cell proliferation, as well as melanoma cell apoptosis in vivo. The outcomes represented that Polyphyllin I promoted A375 cell apoptosis via upregulating Bax level and cleaved caspase-3 level and downregulating Bcl-2 level, inhibited the growth of A375 cells at the G0/G1 phase, and enhanced cell autophagy via regulating the levels of Beclin 1, LC3II, and p62. However, IGF-1 (an activator of PI3K/Akt/mTOR signal pathway) attenuated these changes that Polyphyllin I induced. Furthermore, the xenograft model experiment confirmed that Polyphyllin I treatment suppressed xenograft tumor growth, increased apoptotic index evaluated by the TUNEL method, and reduced the level of Ki67 in tumor tissues in vivo. In conclusion, Polyphyllin I treatment enhanced melanoma cell autophagy and apoptosis, as well as blocked melanoma cell cycle via suppressing PI3K/Akt/mTOR signal pathway. Meanwhile, Polyphyllin I treatment suppressed the development of melanoma in vivo. Therefore, Polyphyllin I possibly is a promising molecular targeted agent used in melanoma therapy.


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