scholarly journals Alpha1-ACT Functions as a Tumour Suppressor in Hepatocellular Carcinoma by Inhibiting the PI3K/AKT/mTOR Signalling Pathway via Activation of PTEN

2017 ◽  
Vol 41 (6) ◽  
pp. 2289-2306 ◽  
Author(s):  
Hanzhang Zhu ◽  
Qiaoyu Liu ◽  
Junwei Tang ◽  
Yu Xie ◽  
Xiaoliang Xu ◽  
...  

Background & Aims: To investigate the expression and prognostic value of α1-ACT (Alpha1-antichymotrypsin) in patients with HCC (hepatocellular carcinoma) and identify the mechanism by which α1-ACT inhibits proliferation and promotes apoptosis of HCC. Methods: We first measured α1-ACT expression levels and determined their relationship with the clinicopathological characteristics and prognosis of patients with HCC.We then established stable HCC cell lines with both α1-ACT overexpression and knockdown and performed a functional analysis in vitro.We first examined the relationship between α1-ACT and the PTEN/PI3K/AKT/mTOR pathway using Western blotting. Then, we determined whether α1-ACT can directly bind to PTEN using co-immunoprecipitation. Finally, we measured α1-ACT expression to evaluate its correlation with the PI3K/AKT/mTOR pathway-related apoptosis proteins in a xenograft tumour mouse model using immunohistochemistry. Results: The α1-ACT expression level was significantly lower in the HCC tissues than in the paratumour tissues and was negatively positively correlated with the level of Ki67, AFP, the AJCC stage, tumour size and tumour invasion. The overexpression of α1-ACT can inhibit cell proliferation and increase cell apoptosis by activating PI3K/AKT/mTOR-mediated apoptosis via binding to PTEN and activating it in vitro. Additionally, the overexpression of α1-ACT can also increase the proportion of cells in the G0/G1 stage by increasing cyclin p21 expression and inhibiting the migration and invasion abilities of HCC cells by regulating MMP2 and MMP9. The xenotransplantation studies with nude mice also showed that overexpression of α1-ACT inhibited tumourigenesis and knockdown of α1-ACT had the opposite effect. Conclusions: Our study demonstrates that α1-ACT suppresses liver cancer development and metastasis via targeting the PTEN/PI3K/AKT/mTOR signalling pathway, which may be a potential target for therapeutic intervention in HCC.

2017 ◽  
Vol 474 (16) ◽  
pp. 2733-2747 ◽  
Author(s):  
Chunyang Du ◽  
Tao Zhang ◽  
Xia Xiao ◽  
Yonghong Shi ◽  
Huijun Duan ◽  
...  

Protease-activated receptor-2 (PAR2), which belongs to a specific class of the G-protein-coupled receptors, is central to several inflammation processes. However, the precise molecular mechanism involved remains undefined. Autophagy has been previously shown to affect inflammation. In the present study, we examine the effect of PAR2 on kidney tubular epithelial autophagy and on autophagy-related inflammation and reveal the underlying mechanism involved. Autophagic activity and levels of autophagic marker LC3 were examined in human kidney tubular epithelial cells with PAR2 knockdown or overexpression. We administered the mammalian target of rapamycin (mTOR) inhibitor (rapamycin) or activator (MHY1485) to investigate the function of the phosphoinositide 3-kinase (PI3K)/Akt/mTOR pathway. We also used transforming growth factor-β1 (TGF-β1)-induced HK-2 cell inflammation models to investigate the role of PAR2-associated autophagy in kidney tubular epithelial inflammation. PAR2 antagonist and rapamycin were administered to mice after unilateral ureteral obstruction to detect the correlations between PAR2, autophagy, and inflammation. Our results show that PAR2 overexpression in HK-2 cells led to a greater reduction in autophagy via the PI3K/Akt/mTOR pathway activation and induces autophagy-related inflammation. Meanwhile, a knockdown of PAR2 via PAR2 RNAi transfection greatly increased autophagy and alleviated autophagy-associated inflammation. In unilateral ureteral obstruction (UUO) kidneys, PAR2 antagonist treatment greatly attenuated renal inflammation and interstitial injury by enhancing autophagy. Moreover, inhibition of mTOR, rapa, markedly increased autophagy and inhibited the UUO-induced inflammation. We conclude that PAR2 induces kidney tubular epithelial inflammation by inhibiting autophagy via the PI3K/Akt/mTOR signalling pathway. Our results are suggestive that PAR2 inhibition may play a role in the treatment of diseases with increased inflammatory responses in renal systems.


2017 ◽  
Vol 44 (1) ◽  
pp. 99-109 ◽  
Author(s):  
Fang Yang ◽  
Lizhi Lv ◽  
Kun Zhang ◽  
Qiucheng Cai ◽  
Jianyong Liu ◽  
...  

Background/Aims: Increasing evidence has indicated that Forkhead box protein C2 (FOXC2) plays an important role in carcinogenesis. However, the expression and the role of FOXC2 in hepatocellular carcinoma (HCC) have not been extensively studied. Methods: FOXC2 expression was analyzed by quantitative real-time polymerase chain reaction, Western blot analysis and immunohistochemistry in HCC tissue and cells. The relationship between FOXC2 expression and patient clinical significance and survival were assessed by Pearson’s correlation and Kaplan-Meier analysis, respectively. Cell proliferation assays, colony formation assays, flow cytometric analysis and Transwell assays were employed to measure the effects of FOXC2 on HCC cells in vitro. Results: The expression of FOXC2 was increased in HCC tissue, and high FOXC2 expression was associated with worse patient survival. Knockdown of FOXC2 inhibited HCC cell growth, migration, and invasion in vitro, as well as tumor growth. Furthermore, we found that activation of AKT-mediated MMP-2 and MMP-9 was involved in FOXC2 promoting an aggressive phenotype. Conclusions: Taken together, these findings demonstrate that FOXC2 is upregulated in HCC tissue and is associated with tumor size, vascular invasion and advanced TNM stage. Further investigation suggested that FOXC2 may play a vital role in promoting proliferation and invasion in HCC and serves as a novel therapeutic target in HCC.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Zhenhong Liu ◽  
Gaofeng Qin ◽  
Lulu Mana ◽  
Shuaiyang Huang ◽  
Yahan Wang ◽  
...  

White matter degeneration and demyelination are nonnegligible pathological manifestations of Alzheimer’s disease (AD). The damage of myelin sheath consisting of oligodendrocytes is the basis of AD’s unique early lesions. Shenzhiling oral liquid (SZL) was the effective Chinese herbal compound approved by the Food and Drug Administration (FDA) for the treatment of AD in China, which plays the exact therapeutic role in clinical AD patients. However, its molecular mechanism remains unclear to date. For this purpose, an in vitro mode of streptozotocin- (STZ-) induced rat oligodendrocyte OLN-93 cell injury was established to mimic the pathological changes of myelin sheath of AD and investigate the mechanism of SZL protecting injured OLN-93 cell. The results showed that STZ can decrease cell viability and downregulate the activity of PI3K/Akt-mTOR signalling pathway and the expression of myelin sheath-related proteins (MBP, MOG, and PLP) in OLN-93 cells. Both SZL-medicated serum and donepezil (positive control) can protect cells from STZ-caused damage. SZL-medicated serum increased OLN-93 cell viability in a dose- and time-dependent manner and enhanced the activity of PI3K/Akt-mTOR signalling pathway. The inhibitor of PI3K (LY294002) inhibited the protective effect of SZL-medicated serum on the STZ-injured OLN-93 cells. Furthermore, rapamycin, the inhibitor of mTOR, inhibited the promotion of cell viability and upregulation of p-mTOR and MBP caused by SZL-medicated serum. In conclusion, our data indicate that SZL plays its therapeutic role on AD by promoting PI3K/Akt-mTOR signalling pathway of oligodendrocytes. Thus, the present study may facilitate the therapeutic research of AD.


2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Wei Cheng ◽  
Ziwei Cheng ◽  
Dongwei Xing ◽  
Minguang Zhang

Hypoxia-inducible factor-1α (HIF-1α) plays a key role by triggering the transcriptional activation of a number of genes involved in migration, invasion, and angiogenesis in hepatocellular carcinoma (HCC). Thus, suppressing tumour growth by targeting the HIF-1α/VEGF signalling pathway represents a promising strategy for the treatment of HCC. In our previous studies, we found that asparagus polysaccharide (ASP) suppressed the proliferation and promoted the apoptosis of HCC cells both in vivo and in vitro. To further explore the potential mechanisms of the antitumor effects of ASP in HCC, we investigated effects of ASP on the migration, invasion, and angiogenesis of HCC cells (SK-Hep1 and Hep-3B) using an in vitro experimental model. First, we found that ASP effectively suppressed the proliferation of the SK-Hep1 and Hep-3B cells but did not cause significant cytotoxicity in normal liver cells (L-O2). Then, we found that ASP inhibited the migration and invasion of the SK-Hep1 and Hep-3B cells and HCC cells-induced angiogenesis of human umbilical vein endothelial cells in a concentration-dependent manner. Mechanistic studies revealed that the inhibition of migration, invasion, and angiogenesis by ASP in the SK-Hep1 and Hep-3B cells might occur via the downregulation of HIF-1α/VEGF signalling pathway. Finally, our results also showed that the inhibition of HIF-1α by ASP may be mediated through the downregulation of the phosphorylation levels of AKT, mTOR, and ERK. In conclusion, our results suggest that ASP suppresses the migration, invasion, and angiogenesis of HCC cells partly via inhibiting the HIF-1α/VEGF signalling pathway.


2016 ◽  
Vol 38 (2) ◽  
pp. 836-846 ◽  
Author(s):  
Liyang Dong ◽  
Junwei Ni ◽  
Wenhao Hu ◽  
Chang Yu ◽  
Haiyan Li

Background/Aims: PlncRNA-1 has been demonstrated to promote malignancy in various cancers. The present study aims to investigate the expression pattern, prognosis value and the function of PlncRNA-1 in human hepatocellular carcinoma (HCC). Methods: The expression of PlncRNA-1 in 84 pairs of HCC and their matched normal tissues was examined by quantitative real-time polymerase chain reaction (qRT-PCR). The correlations of PlncRNA-1 expression and clinicopathological characteristics and prognosis were also analyzed. The biological role of PlncRNA-1 in cell proliferation, migration and invasion was examined in vitro and in vivo. Results: The results showed that the level of PlncRNA-1 expression was significantly increased in HCC tissues and significantly correlated with tumor size, vascular invasion and advanced TNM stage. Moreover, patients with high levels of PlncRNA-1 expression had relatively poor prognostic outcomes, serving as an independent prognostic factor for HCC. In vitro functional assays indicated that knockdown of PlncRNA-1 expression significantly reduced cell proliferation, migration and invasion by inhibiting the epithelial-mesenchymal transition (EMT) signaling. Animal model experiments confirmed the ability of PlncRNA-1 to promote tumor growth in vivo. Conclusions: Taken together, our findings suggest that PlncRNA-1 may serve as an oncogene in HCC progression and represent a valuable prognostic marker and potential therapeutic target for HCC.


2020 ◽  
Vol 122 (5) ◽  
pp. 705-714 ◽  
Author(s):  
Yu Liang ◽  
Danxi Zhu ◽  
Lidan Hou ◽  
Yu Wang ◽  
Xin Huang ◽  
...  

Abstract Background Chemoresistance remains a critical event that accounts for colorectal cancer (CRC) lethality. The aim of this study is to explore the ability of dichloroacetate (DCA) to increase chemosensitivity in CRC and the molecular mechanisms involved. Methods The effects of combination treatment of DCA and oxaliplatin (L-OHP) were analysed both in vitro and in vivo. The DCA-responsive proteins in AMPK pathway were enriched using proteomic profiling technology. The effect of DCA on CAB39–AMPK signal pathway was analysed. In addition, miRNA expression profiles after DCA treatment were determined. The DCA-responsive miRNAs that target CAB39 were assayed. Alterations of CAB39 and miR-107 expression were performed both in vitro and on xenograft models to identify miR-107 that targets CAB39–AMPK–mTOR signalling pathway. Results DCA increased L-OHP chemosensitivity both in vivo and in vitro. DCA could upregulate CAB39 expression, which activates the AMPK/mTOR signalling pathway. CAB39 was confirmed to be a direct target of miR-107 regulated by DCA. Alterations of miR-107 expression were correlated with chemoresistance development in CRC both in vitro and in vivo. Conclusion These findings suggest that the miR-107 induces chemoresistance through CAB39–AMPK–mTOR pathway in CRC cells, thus providing a promising target for overcoming chemoresistance in CRC.


Reproduction ◽  
2019 ◽  
Vol 157 (5) ◽  
pp. 475-484 ◽  
Author(s):  
Song Li ◽  
Qi Fan ◽  
Yanqiu Xie ◽  
Haiyan Lin ◽  
Qi Qiu ◽  
...  

In vitro activation of primordial follicles is becoming more essential in assisted reproductive technologies. Vasoactive intestinal peptide (VIP) is one of the members of the neurotrophin family which has demonstrated to have an impact on follicle development in recent years. This study aims to investigate the effect of VIP on the activation of primordial follicles in neonatal rat in an in vitro culture system and to determine the relevant molecular mechanism of their activation. Ovaries of 4-day-old rats were examined for the expression of VIP receptors and were cultured in mediums containing VIP with or without inhibitors of the ERK–mTOR signalling pathway. They were then collected for histological analysis or measurement of the molecular expression of this pathway. The receptors of VIP were found in granular cells and oocytes of primordial and early-growing follicles in neonatal ovary. The ratio of growing follicle increased in the presence VIP at different concentrations, with the highest level of increase being observed in the 10−7 mol/L VIP-treated group. The ratio of PCNA-positive granular cells was also increased, while that of the apoptotic oocytes were decreased, and protein analysis showed increased phosphorylation of ERK1/2, mTOR and RPS6 in the VIP-treated group. However, the effect of VIP on the activation of primordial follicle became insignificant with the addition of MEK inhibitor (U0126) or mTORC1 inhibitor (rapamycin). This study indicated that VIP could activate neonatal rat primordial follicle through the ERK-mTOR signalling pathway, suggesting a strategy for in vitro primordial follicle recruitment.


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