scholarly journals HBV Infection Promotes The Occurrence and Development of Hepatocellular Carcinoma Through Impairing The Inhibitory Effect of PPP2R5A on MAPK/AKT/WNT Signaling Pathway

Author(s):  
Xuejing Lin ◽  
Ziming Mao ◽  
Lei Chen ◽  
Haihua Qian ◽  
Chunying Liu ◽  
...  

Abstract Background: Reversible phosphorylation and dephosphorylation play important roles in cell function and cell signal transduction. PPP2R5A is responsible for specifically regulating the catalytic function, substrate specificity and intracellular localization of the tumor suppressor phosphatase PP2A. Therefore, the abnormal expression and function of PPP2R5A may be related to the occurrence and development of tumors.Results: This study showed that PPP2R5A inhibited the proliferation and metastasis of hepatocellular carcinoma (HCC) cells, and acted as a tumor suppressor in HCC cells, but it had no significant effect on cell cycle. Further research found that PPP2R5A exerted tumor suppressor efficacy by inhibiting the MAPK/AKT/WNT signaling pathway. Combined with analysis of clinical tissue samples and TCGA database, it was found that the expression of PPP2R5A in tumor tissues of Chinese HCC patients was down-regulated and significantly correlated with the progression-free survival (PFS) of HCC patients. On the contrary, PPP2R5A showed an up-regulation trend in HCC cases in TCGA database although its effect on PFS was the same with that in Chinese HCC patients. HBV infection is the main pathogenic factor of HCC in China. It was found that hepatitis B virus (HBV) infection reduced the content of PPP2R5A in cells.Conclusions: It was concluded that HBV inhibited the initiation of the protective mechanism mediated by PPP2R5A, making the occurrence and progress of HCC more "unimpeded". This conclusion will further reveal the role of PPP2R5A in HBV-induced and HBV-unrelated HCC, therefore, providing clues for the prevention and treatment of the two types of HCC, respectively.

2019 ◽  
Vol 51 (11) ◽  
pp. 1-20 ◽  
Author(s):  
Jun-Cheng Guo ◽  
Yi-Jun Yang ◽  
Jin-Fang Zheng ◽  
Jian-Quan Zhang ◽  
Min Guo ◽  
...  

AbstractHepatocellular carcinoma (HCC) is a major cause of cancer-related deaths, but its molecular mechanisms are not yet well characterized. Long noncoding RNAs (lncRNAs) play crucial roles in tumorigenesis, including that of HCC. However, the role of homeobox A11 antisense (HOXA11-AS) in determining HCC stem cell characteristics remains to be explained; hence, this study aimed to investigate the effects of HOXA11-AS on HCC stem cell characteristics. Initially, the expression patterns of HOXA11-AS and HOXA11 in HCC tissues, cells, and stem cells were determined. HCC stem cells, successfully sorted from Hep3B and Huh7 cells, were transfected with short hairpin or overexpression plasmids for HOXA11-AS or HOXA11 overexpression and depletion, with an aim to study the influences of these mediators on the self-renewal, proliferation, migration, and tumorigenicity of HCC stem cells in vivo. Additionally, the potential relationship and the regulatory mechanisms that link HOXA11-AS, HOXA11, and the Wnt signaling pathway were explored through treatment with Dickkopf-1 (a Wnt signaling pathway inhibitor). HCC stem cells showed high expression of HOXA11-AS and low expression of HOXA11. Both HOXA11-AS silencing and HOXA11 overexpression suppressed the self-renewal, proliferation, migration, and tumorigenicity of HCC stem cells in vivo, as evidenced by the decreased expression of cancer stem cell surface markers (CD133 and CD44) and stemness-related transcription factors (Nanog, Sox2, and Oct4). Moreover, silencing HOXA11-AS inactivated the Wnt signaling pathway by decreasing the methylation level of the HOXA11 promoter, thereby inhibiting HCC stem cell characteristics. Collectively, this study suggested that HOXA11-AS silencing exerts an antitumor effect, suppressing HCC development via Wnt signaling pathway inactivation by decreasing the methylation level of the HOXA11 promoter.


2017 ◽  
Vol 38 (4) ◽  
pp. 2351-2359 ◽  
Author(s):  
Chunlin Jiang ◽  
Miao Yu ◽  
Xiaoyan Xie ◽  
Guangliang Huang ◽  
Yao Peng ◽  
...  

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Asma Saleem ◽  
Eric W Howard ◽  
Latonya F Been ◽  
Megan Lerner ◽  
Daniel Brackett ◽  
...  

Type 2 (non-insulin-dependent) diabetes mellitus (T2DM) is associated with a marked increase in the risk of coronary heart disease. The discovery of TCF7L2 as a global T2DM gene has triggered investigations to explore the clinical utility of its variants for guiding the development of new diagnostic and therapeutic strategies. However, interpreting the resulting associations into function still remains unclear. Canonical Wnt signaling regulates β-catenin and its binding with TCF7L2, which in turn is critical for the production of glucagon like protein-1 (GLP-1). This study examines the role of a novel frame-shift insertion discovered in a conserved region of WNT16a, and it is proposed that this mutation affects T2DM susceptibility in conjunction with gene variants in TCF7L2. Our results predicted that the insertion would convert the upstream open reading frame in the Wnt16a mRNA to an alternative, in-frame translation initiation site, resulting in the prevention of nonsense-mediated decay that would normally occur in the wild-type message, leading to a consequent stabilization of the mutated WNT16a message. To examine the role of Wnt16a in the Wnt signaling pathway, DNA and serum samples from 2,034 individuals (48% with T2DM) from the Sikh Diabetes Study were used in this investigation, of which 32% were WNT16a insertion carriers. There was a 3.2 fold increase in Wnt16a mRNA levels in pancreatic tissues from the insertion carriers and a significant increase (70%, p<0.0001) in luciferase activity in the constructs carrying the insertion. The expression of TCF7L2 mRNA in pancreas was also elevated (~23-fold) among the insertion carriers (p=0.003). Our results suggest synergistic effects of WNT16a insertion mutants and the at-risk ‘T ‘allele of TCF7L2 (rs7903146) for compounding the risk of T2DM, perhaps by impacting genes related to β-cell function in the Wnt/β-catenin/TCF7L2 signaling pathway.


2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Surbhi Chouhan ◽  
Snahlata Singh ◽  
Dipti Athavale ◽  
Pranay Ramteke ◽  
Vimal Pandey ◽  
...  

2021 ◽  
Vol 11 ◽  
Author(s):  
Juan Xiong ◽  
Panpan Jiang ◽  
Li Zhong ◽  
Youling Wang

ObjectClinically, the effective treatment options available to thyroid cancer (THCA) patients are very limited. Elucidating the features of tumor suppressor genes (TSGs) and the corresponding signal transduction cascade may provide clues for the development of new strategies for targeted therapy of THCA. Therefore, this paper aims to explore the mechanism of ZNF24 underlying promoting THCA cell senescence at molecular level.MethodsWe performed RT-PCR and Western Blotting for evaluating associated RNA and protein expression. CCK8, colony forming, wound healing and Transwell chamber assays were conducted to examine THCA cell proliferation, invasion and migration. β-galactosidase staining assay was performed to detect THCA cells senescence. The size and volume of xenotransplanted tumors in nude mice are calculated to asses ZNF24 effect in vivo.ResultsEctopic expression of ZNF24 significantly inhibited the cell viability, colony forming, migration and invasion abilities of THCA cell lines (K1/GLAG-66i and BCPAPi) (P &lt; 0.05). ZNF24 induced BCPAPi cells senescence through regulating Wnt signaling pathway. ZNF24 inhibited Wnt signaling pathway activition by competitively binding β-catenin from LEF1/TCF1-β-catenin complex. In nude mice, both Ectopic expression of ZNF24 and 2,4-Da (the strong β-catenin/Tcf-4 inhibitor) treatment significantly decreased both the size and weight of xenotransplanted tumors when compared with control mice (P &lt; 0.05).ConclusionResults obtained in vivo and in vitro reveal the role of ZNF24 in significantly suppressing THCA tumorigenesis and invasion by regulating Wnt signaling pathway.


Cells ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 1020 ◽  
Author(s):  
Hang-Lung Chang ◽  
Oluwaseun Adebayo Bamodu ◽  
Jiann-Ruey Ong ◽  
Wei-Hwa Lee ◽  
Chi-Tai Yeh ◽  
...  

Background: With recorded under-performance of current standard therapeutic strategies as highlighted by high rates of post-treatment (resection or local ablation) recurrence, resistance to chemotherapy, poor overall survival, and an increasing global incidence, hepatocellular carcinoma (HCC) constitutes a medical challenge. Accumulating evidence implicates the presence of HCC stem cells (HCC-SCs) in HCC development, drug-resistance, recurrence, and progression. Therefore, treatment strategies targeting both HCC-SCs and non-CSCs are essential. Methods: Recently, there has been an increasing suggestion of MALAT1 oncogenic activity in HCC; however, its role in HCC stemness remains unexplored. Herein, we investigated the probable role of MALAT1 in the SCs-like phenotype of HCC and explored likely molecular mechanisms by which MALAT1 modulates HCC-SCs-like and metastatic phenotypes. Results: We showed that relative to normal, cirrhotic, or dysplastic liver conditions, MALAT1 was aberrantly expressed in HCC, similar to its overexpression in Huh7, Mahlavu, and SK-Hep1 HCC cells lines, compared to the normal liver cell line THLE-2. We also demonstrated a positive correlation between MALAT1 expression and poor cell differentiation status in HCC using RNAscope. Interestingly, we demonstrated that shRNA-mediated silencing of MALAT1 concomitantly downregulated the expression levels of β-catenin, Stat3, c-Myc, CK19, vimentin, and Twist1 proteins, inhibited HCC oncogenicity, and significantly suppressed the HCC-SCs-related dye-effluxing potential of HCC cells and reduced their ALDH-1 activity, partially due to inhibited MALAT1-β-catenin interaction. Additionally, using TOP/FOP (TCL/LEF-Firefly luciferase) Flash, RT-PCR, and western blot assays, we showed that silencing MALAT1 downregulates β-catenin expression, dysregulates the canonical Wnt signaling pathway, and consequently attenuates HCC tumorsphere formation efficiency, with concurrent reduction in CD133+ and CD90+ HCC cell population, and inhibits tumor growth in SK-Hep1-bearing mice. Conclusions: Taken together, our data indicate that MALAT1/Wnt is a targetable molecular candidate, and the therapeutic targeting of MALAT1/Wnt may constitute a novel promising anticancer strategy for HCC treatment.


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