scholarly journals PKM2-Induced the Phosphorylation of Histone H3 Contributes to EGF-Mediated PD-L1 Transcription in HCC

2020 ◽  
Vol 11 ◽  
Author(s):  
Xiao Wang ◽  
Chao Liang ◽  
Xin Yao ◽  
Ruo-Han Yang ◽  
Zhan-Sheng Zhang ◽  
...  

High expression of programmed death-ligand-1 (PD-L1) in hepatocellular carcinoma (HCC) cells usually inhibits the proliferation and functions of T cells, leading to immune suppression in tumor microenvironment. However, very little has been described regarding the mechanism of PD-L1 overexpression in HCC cells. In the present study, we found epidermal growth factor (EGF) stimulation promoted the expression of PD-L1 mRNA and protein in HCC cells. Inhibition of epidermal growth factor receptor (EGFR) could reverse EGF-induced the expression of PD-L1 mRNA and protein. Subsequently, we also observed that the phosphorylation level of Pyruvate kinase isoform M2 (PKM2) at Ser37 site was also increased in response to EGF stimulation. Expression of a phosphorylation-mimic PKM2 S37D mutant stimulated PD-L1 expression as well as H3-Thr11 phosphorylation in HCC cells, while inhibition of PKM2 significantly blocked EGF-induced PD-L1 expression and H3-Thr11 phosphorylation. Furthermore, mutation of Thr11 of histone H3 into alanine abrogated EGF-induced mRNA and protein expression of PD-L1, Chromatin immunoprecipitation (ChIP) assay also suggested that EGF treatment resulted in enhanced H3-Thr11 phosphorylation at the PD-L1 promoter. In a diethylnitrosamine (DEN)-induced rat model of HCC, we found that the expression of phosphorylated EGFR, PKM2 nuclear expression, H3-Thr11 phosphorylation as well as PD-L1 mRNA and protein was higher in the livers than that in normal rat livers. Taken together, our study suggested that PKM2-dependent histone H3-Thr11 phosphorylation was crucial for EGF-induced PD-L1 expression at transcriptional level in HCC. These findings may provide an alternative target for the treatment of hepatocellular carcinoma.

2021 ◽  
Vol 21 ◽  
Author(s):  
Hadeer Abosalema ◽  
Shahenda Mahgoub ◽  
Mohamed Emara ◽  
Nahla Kotb ◽  
Sameh Soror

: Hepatocellular carcinoma (HCC) is a major health problem worldwide. Most patients are diagnosed for the first time at late stages; this leads to a very poor prognosis. It is challenging to discover strategies for treatment at these advanced stages. Recently, monoclonal antibodies (mAbs) targeting specific cellular signaling pathways in HCC have been developed. Unfortunately, they still have a low survival rate, and some of them failed clinically to produce effective responses even if they showed very good results against HCC in preclinical studies. This review focuses on and discusses the possible causes for the failure of mAbs, precisely anti-Epidermal Growth Factor Receptor (EGFR) mAb and the crosstalk between this mAb and patients' NK cells.


PRILOZI ◽  
2018 ◽  
Vol 39 (2-3) ◽  
pp. 21-28
Author(s):  
Dafina Nikolova ◽  
Viktorija Chalovska ◽  
Magdalena Genadieva Ivanova ◽  
Emilija Nikolovska ◽  
Ance Volkanovska ◽  
...  

Abstract Introduction: Epidermal growth factor receptor (EGFR) signaling plays an important role in various cancers, including hepatocellular carcinoma (HCC). We aimed to evaluate immunoexpression of EGFR in HCC and surrounding non-tumor liver tissue and to correlate it to multiple clinicopathologic data. Material and Methods: We analyzed 60 patients with HCC for multiple clinicopathologic characteristics and survival. Presence of the immunosignal and the percentage of positive tumor cells at the whole tumor tissue sample and adjacent cirrhotic liver tissue were semi-quantitatively determined. Results: Nineteen patients (31.67%) were female and 41 (68.33%) were male ranging in age from 31 to 85 years, median 61.88±10.51. Mean survival time for female patients was 8.86±1.76 months, for male 13.03±1.50 months and overall survival was 11.6051±1.19 months. The most patients had: T2 status (41.67%), no enlarged lymph nodes (90%), vascular invasion (63.33%) and well differentiated (43.33%) tumors. EGFR immunoexpression was determined in range from 0% to 100% in both tumor and non-tumor tissue with mean value of 39.58% in tumor and 86.86% in cirrhotic tissue (p<0.00). Higher percent of tumor EGFR positive cells were found in cases with higher T status, higher levels of AFP and poorly differentiated carcinoma, but not significantly. Lower percent of tumor EGFR positive cells were found in patients with vascular invasion and enlarged lymph nodes, but also not significantly. EGFR expression in tumor tissue significantly influenced survival of the patients (p<0.05). Conclusion: The study showed that expression of EGFR in lower percentage of tumor cells was associated to favorable prognosis, making it a potential prognostic marker and therapeutic target.


Tumor Biology ◽  
2017 ◽  
Vol 39 (3) ◽  
pp. 101042831769502 ◽  
Author(s):  
Kai Liu ◽  
Dongdong Lin ◽  
Yabo Ouyang ◽  
Lijun Pang ◽  
Xianghua Guo ◽  
...  

Overexpression of apoptosis-stimulating protein 2 of p53 (ASPP2) induces apoptotic cell death in hepatoma cells (e.g. HepG2 cells) by enhancing the transactivation activity of p53, but long-term ASPP2 overexpression fails to induce more apoptosis since activation of the epidermal growth factor/epidermal growth factor receptor/SOS1 pathway impairs the pro-apoptotic role of ASPP2. In this study, in recombinant adenovirus-ASPP2-infected HepG2 cells, ASPP2 overexpression induces amphiregulin expression in a p53-dependent manner. Although amphiregulin initially contributes to ASPP2-induced apoptosis, it eventually impairs the pro-apoptotic function of ASPP2 by activating the epidermal growth factor/epidermal growth factor receptor/SOS1 pathway, leading to apoptosis resistance. Moreover, blocking soluble amphiregulin with a neutralizing antibody also significantly increased apoptotic cell death of HepG2 cells due to treatment with methyl methanesulfonate, cisplatin, or a recombinant p53 adenovirus, suggesting that the function of amphiregulin involved in inhibiting apoptosis may be a common mechanism by which hepatoma cells escape from stimulus-induced apoptosis. Thus, our data elucidate an apoptosis-evasion mechanism in hepatocellular carcinoma and have potential implications for hepatocellular carcinoma therapy.


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