scholarly journals PTP4A3, A Novel Target Gene of HIF-1alpha, Participates in Benzene-Induced Cell Proliferation Inhibition and Apoptosis through PI3K/AKT Pathway

Author(s):  
Yunqiu Pu ◽  
Fengxia Sun ◽  
Rongli Sun ◽  
Zhaodi Man ◽  
Shuangbin Ji ◽  
...  

Benzene, a commonly used chemical, has been confirmed to specifically affect the hematopoietic system as well as overall human health. PTP4A3 is overexpressed in leukemia cells and is related to cell proliferation. We previously found that HIF-1alpha was involved in benzene toxicity and PTP4A3 may be the target gene of HIF-1alpha via ChIP-seq. The aim of this study is to confirm the relationship between HIF-1alpha and PTP4A3 in benzene toxicity, as well as the function of PTP4A3 on cell toxicity induced by 1,4-benzoquinone (1,4-BQ). Our results indicate that HIF-1alpha could regulate PTP4A3 with in vivo and in vitro experiments. A cell line with suppressed PTP4A3 was established to investigate the function of PTP4A3 in 1,4-BQ toxicity in vitro. The results revealed that cell proliferation inhibition was more aggravated in PTP4A3 low-expression cells than in the control cells after 1,4-BQ treatment. The relative oxygen species (ROS) significantly increased in cells with inhibited PTP4A3, while the rise was inferior to the control cells at the 20 μM 1,4-BQ group. An increase in DNA damage was seen in PTP4A3 down-regulated cells at the 10 μM 1,4-BQ group, whereas the results reversed at the concentration of 20 μM. Moreover, the apoptosis rate increased higher in down-regulated PTP4A3 cells after 1,4-BQ exposure. In addition, PI3K/AKT pathway was significantly restrained in cells with inhibited PTP4A3 after 1,4-BQ treatment. Our results indicate that HIF-1alpha may regulate PTP4A3 to be involved in benzene toxicity. Inhibition of PTP4A3 could aggravate cell proliferation suppression and apoptosis by regulating PI3K/AKT pathway after 1,4-BQ treatment.

2018 ◽  
Vol 46 (4) ◽  
pp. 1311-1325 ◽  
Author(s):  
Tao Tian ◽  
Chun-Li Li ◽  
Xiao Fu ◽  
Shu-Hong Wang ◽  
Jun Lu ◽  
...  

Objective To explore the role and mechanism of β1 integrin in the regulation of multicellular drug resistance in hepatocellular carcinoma (HCC). Methods This in vitro study used a liquid overlay technique to obtain multicellular spheroids of two human HCC cell lines, HepG2 and Bel-7402. The morphology of the spheroids was observed by optical and electron microscopy. The effects of exposure to 5-fluorouracil (5-FU) and cisplatin (CDDP) on cell proliferation and the induction of apoptosis were assessed in monolayer cells and multicellular spheroids. The levels of β1 integrin and the effects on the focal adhesion kinase (FAK)/protein kinase B (Akt) pathway were evaluated using Western blot analysis, immunofluorescence and flow cytometry. The role of β1 integrin was confirmed by using an inhibitory antibody. Results Cell proliferation inhibition and cell apoptosis induced by 5-FUl and CDDP were abrogated in multicellular spheroids compared with monolayer cells. There were high levels of β1 integrin in multicellular spheroids. β1 integrin inhibitory antibody prevented the formation of multicellular spheroids, coupled with a significant increase in proliferation inhibition and apoptosis induction. β1 integrin inhibitory antibody effectively suppressed activation of both FAK and Akt in multicellular spheroids. Conclusions β1 integrin mediated multicellular drug resistance through the FAK/Akt pathway in HCC spheroids.


2018 ◽  
Vol 50 (2) ◽  
pp. 612-628 ◽  
Author(s):  
Yaodong Zhang ◽  
Guwei Ji ◽  
Sheng Han ◽  
Zicheng Shao ◽  
Zefa Lu ◽  
...  

Background/Aims: Aberrant expression of Tip60 is associated with progression in many cancers. However, the role of Tip60 in cancer progression remains contradictory. The aim of this study was to investigate the clinical significance, biological functions and underlying mechanisms of Tip60 deregulation in cholangiocarcinoma (CCA) for the first time. Methods: Quantitative real-time PCR (QRT-PCR), western blotting and immunohistochemistry staining (IHC) were carried out to measure Tip60 expression in CCA tissues and cell lines. Kaplan–Meier analysis and the log-rank test were used for survival analysis. In vitro, cell proliferation was evaluated by flow cytometry and CCK-8, colony formation, and EDU assays. Migration/ invasion was evaluated by trans-well assays. Phosphokinase array was used to confirm the dominant signal regulated by Tip60. Tumor growth and metastasis were demonstrated in vivo using a mouse model. Results: Tip60 was notably downregulated in CCA tissues, which was associated with greater tumor size, venous invasion, and TNM stage. Down-regulation of Tip60 was associated with tumor progression and poorer survival in CCA patients. In vitro and in vivo studies demonstrated that Tip60 suppressed growth and metastasis throughout the progression of CCA. We further identified the PI3K/AKT pathway as a dominant signal of Tip60 and suggested that Tip60 regulated CCA cell proliferation and metastasis via PT3K-AKT pathway. Pearson analysis revealed that PTEN was positively correlated with the Tip60 level in CCA tissues. Conclusion: Tip60, as a tumor suppressor in CCA via the PI3K/AKT pathway, might be a promising therapeutic target or prognostic marker for CCA.


Author(s):  
Xiao Xue Ke ◽  
Rui Zhang ◽  
Xi Zhong ◽  
Lei Zhang ◽  
Hongjuan Cui

Glioblastoma is an aggressive and difficult to treat cancer. Recent data have emerged implicating that histone modification level may play a crucial role in glioma genesis. The histone lysine methyltransferase G9a is mainly responsible for the mono- and di-methylation of histone H3 lysine 9 (H3K9), whose overexpression is associated with a more aggressive phenotype in cancer. However, the detailed correlations between G9a and glioblastoma genesis remain to be further elucidated. Here, we show that G9a is essential for glioblastoma carcinogenesis and reveal a probable mechanism of it in cell proliferation control. We found that G9a was highly expressed in glioblastoma cells, and knockdown or inhibition of G9a significantly repressed cell proliferation and tumorigenesis ability both in vitro and in vivo. Besides, knockdown or inhibition of G9a led to a cell cycle arrest in G2 phase, as well as decreased the expression of CDK1, CDK2, Cyclin A2, and Cyclin B1, while it induced the activation of autophagy. Further investigation showed that G9a deficiency induced cell proliferation suppression, and activation of autophagy was rescued by overexpression of the full-length c-Myc. Chromatin immunoprecipitation (ChIP) assay showed that G9a was enriched on the −2267 to −1949 region of the c-Myc promoter in LN-229 cells and the −1949 to −1630 region of the c-Myc promoter in U-87 MG cells. Dual-luciferase reporter assay showed that c-Myc promoter activity was significantly reduced after knockdown or inhibition of G9a. Our study shows that G9a controls glioblastoma cell proliferation by transcriptionally modulating oncogene c-Myc and provides insight into the capabilities of G9a working as a potential therapeutic target in glioblastoma.


2019 ◽  
Vol 10 (10) ◽  
Author(s):  
Xiaonan Xi ◽  
Ning Liu ◽  
Qianqian Wang ◽  
Yahui Chu ◽  
Zheng Yin ◽  
...  

Abstract PAI-1 plays significant roles in cancer occurrence, relapse and multidrug resistance and is highly expressed in tumours. ACT001, which is currently in phase I clinical trials for the treatment of glioblastoma (GBM). However, the detailed molecular mechanism of ACT001 is still unclear. In this study, we investigated the effects of ACT001 on glioma cell proliferation and clarified its mechanism. We discovered that PAI-1 was the direct target of ACT001 by a cellular thermal shift assay. Then, the interaction between ACT001 and PAI-1 was verified by Biacore assays, thermal stability assays and ACT001 probe assays. Furthermore, from the proteomic analysis, we found that ACT001 directly binds PAI-1 to inhibit the PI3K/AKT pathway, which induces the inhibition of glioma cell proliferation, invasion and migration. Moreover, the combination of ACT001 and cisplatin showed a synergistic effect on the inhibition of glioma in vitro and in vivo. In conclusion, our findings demonstrate that PAI-1 is a new target of ACT001, the inhibition of PAI-1 induces glioma inhibition, and ACT001 has a synergistic effect with cisplatin through the inhibition of the PAI-1/PI3K/AKT pathway.


Blood ◽  
2020 ◽  
Author(s):  
Shirong Li ◽  
Jing Fu ◽  
Jun Yang ◽  
Huihui Ma ◽  
Divaya Bhutani ◽  
...  

In multiple myeloma (MM), frequent mutations of NRAS, KRAS, or BRAF are found in up to 50% of newly diagnosed patients. The majority of the NRAS, KRAS, and BRAF mutations occur in hotspots causing constitutive activation of the corresponding proteins. Thus targeting RAS mutation in MM will increase therapeutic efficiency and potentially overcome drug-resistance. We identified Germinal Center Kinase (GCK) as a novel therapeutic target in MM with RAS mutation. GCK knockdown in MM cells demonstrated in vitro and in vivo that silencing of GCK induces MM cell growth inhibition, associated with blocked MKK4/7-JNK phosphorylation and impaired degradation of IKZF1/3, BCL-6, and c-MYC. These effects were rescued by overexpression of an shRNA-resistant GCK, thereby excluding the potential off-target effects of GCK knockdown. In contrast, overexpression of shRNA-resistant GCK kinase-dead mutant (K45A) inhibited MM cell proliferation and failed to rescue the effects of GCK knockdown on MM growth inhibition, indicating that GCK kinase activity is critical for regulating MM cell proliferation and survival. Importantly, the higher sensitivity to GCK knockdown in RASMut cells suggests that targeting GCK is effective in multiple myeloma which harbors RAS mutations. In accordance with the effects of GCK knockdown, the GCK inhibitor TL4-12 dose-dependently downregulated IKZF1 and BCL-6 and led to MM cell proliferation inhibition accompanied by induction of apoptosis. Hereby our data identify GCK as a novel target in RASMut MM cells, providing a rationale to treat RAS mutations in MM. Furthermore, GCK inhibitors might represent an alternative therapy to overcome IMiD-resistance in MM.


2016 ◽  
Vol 47 ◽  
pp. 1-7 ◽  
Author(s):  
Delphine Manzoni ◽  
Régine Catallo ◽  
Amel Chebel ◽  
Lucile Baseggio ◽  
Anne-Sophie Michallet ◽  
...  

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Xinchen Yang ◽  
Shikun Yang ◽  
Jinhua Song ◽  
Wenjie Yang ◽  
Yang Ji ◽  
...  

AbstractGrowing evidence demonstrates that MicroRNAs (miRNAs) play an essential role in contributing to tumor development and progression. However, the underlying role and mechanisms of miR-23b-5p in hepatocellular carcinoma (HCC) formation remain unclear. Our study showed that miR-23b-5p was downregulated in the HCC tissues and cell lines, and lower expression of miR-23b-5p was associated with more severe tumor size and poorer survival. Gain- or loss-of-function assays demonstrated that miR-23b-5p induced G0/G1 cell cycle arrest and inhibited cell proliferation both in vitro and in vivo. qRT-PCR, western blot and luciferase assays verified that Mammalian transcription factor Forkhead Box M1 (FOXM1), upregulated in HCC specimens, was negatively correlated with miR-23b-5p expression and acted as a direct downstream target of miR-23b-5p. In addition, miR-23b-5p could regulate cyclin D1 and c-MYC expression by directly targeting FOXM1. Further study revealed that restoration of FOXM1 neutralized the cell cycle arrest and cell proliferation inhibition caused by miR-23b-5p. Taken together, our findings suggest that miR-23b-5p acted as a tumor suppressor role in HCC progression by targeting FOXM1 and may serve as a potential novel biomarker for HCC diagnosis and prognosis.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Shujun Cao ◽  
Na Li ◽  
Xihong Liao

Abstract Background Ovarian cancer is the leading lethal gynecological cancer and is generally diagnosed during late-stage presentation. In addition, patients with ovarian cancer still face a low 5-year survival rate. Thus, innovative molecular targeting agents are required to overcome this disease. The present study aimed to explore the function of miR-362-3p and the underlying molecular mechanisms influencing ovarian cancer progression. Methods The expression levels of miR-362-3p were determined using qRT-PCR. Gain-of-function and loss-of-function methods were used to detect the effects of miR-362-3p on cell proliferation, cell migration, and tumor metastasis in ovarian cancer. A luciferase reporter assay was performed to confirm the potential target of miR-362-3p, and a rescue experiment was employed to verify the effect of miR-362-3p on ovarian cancer by regulating its target gene. Results miR-362-3p was significantly downregulated in ovarian cancer tissues and cell lines. In vitro, our data showed that miR-362-3p suppressed cell proliferation and migration. In vivo, miR-362-3p inhibited ovarian cancer growth and metastasis. Mechanistically, SERBP1 was identified as a direct target and functional effector of miR-362-3p in ovarian cancer. Moreover, SERBP1 overexpression rescued the biological function of miR-362-3p. Conclusions Our data reveal that miR-362-3p has an inhibitory effect on ovarian cancer. miR-362-3p inhibits the development and progression of ovarian cancer by directly binding its target gene SERBP1.


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