scholarly journals Ezrin Modulates the Cell Surface Expression of Programmed Cell Death Ligand-1 in Human Cervical Adenocarcinoma Cells

Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5648
Author(s):  
Chihiro Tanaka ◽  
Takuro Kobori ◽  
Mayuka Tameishi ◽  
Yoko Urashima ◽  
Takuya Ito ◽  
...  

Cancer cells employ programmed cell death ligand-1 (PD-L1), an immune checkpoint protein that binds to programmed cell death-1 (PD-1) and is highly expressed in various cancers, including cervical carcinoma, to abolish T-cell-mediated immunosurveillance. Despite a key role of PD-L1 in various cancer cell types, the regulatory mechanism for PD-L1 expression is largely unknown. Understanding this mechanism could provide a novel strategy for cervical cancer therapy. Here, we investigated the influence of ezrin/radixin/moesin (ERM) family scaffold proteins, crosslinking the actin cytoskeleton and certain plasma membrane proteins, on the expression of PD-L1 in HeLa cells. Our results showed that all proteins were expressed at mRNA and protein levels and that all ERM proteins were highly colocalized with PD-L1 in the plasma membrane. Interestingly, immunoprecipitation assay results demonstrated that PD-L1 interacted with ERM as well as actin cytoskeleton proteins. Furthermore, gene silencing of ezrin, but not radixin and moesin, remarkably decreased the protein expression of PD-L1 without affecting its mRNA expression. In conclusion, ezrin may function as a scaffold protein for PD-L1; regulate PD-L1 protein expression, possibly via post-translational modification in HeLa cells; and serve as a potential therapeutic target for cervical cancer, improving the current immune checkpoint blockade therapy.

2021 ◽  
Vol 14 (9) ◽  
pp. 864
Author(s):  
Takuro Kobori ◽  
Chihiro Tanaka ◽  
Mayuka Tameishi ◽  
Yoko Urashima ◽  
Takuya Ito ◽  
...  

Programmed cell death ligand-1 (PD-L1), an immune checkpoint protein highly expressed on the cell surface in various cancer cell types, binds to programmed cell death-1 (PD-1), leading to T-cell dysfunction and tumor survival. Despite clinical successes of PD-1/PD-L1 blockade therapies, patients with colorectal cancer (CRC) receive little benefit because most cases respond poorly. Because high PD-L1 expression is associated with immune evasion and poor prognosis in CRC patients, identifying potential modulators for the plasma membrane localization of PD-L1 may represent a novel therapeutic strategy for enhancing the efficacy of PD-1/PD-L1 blockade therapies. Here, we investigated whether PD-L1 expression in human colorectal adenocarcinoma cells (LS180) is affected by ezrin/radixin/moesin (ERM), functioning as scaffold proteins that crosslink plasma membrane proteins with the actin cytoskeleton. We observed colocalization of PD-L1 with all three ERM proteins in the plasma membrane and detected interactions involving PD-L1, the three ERM proteins, and the actin cytoskeleton. Furthermore, gene silencing of ezrin and radixin, but not of moesin, substantially decreased the expression of PD-L1 on the cell surface without affecting its mRNA level. Thus, in LS180 cells, ezrin and radixin may function as scaffold proteins mediating the plasma membrane localization of PD-L1, possibly by post-translational modification.


2021 ◽  
Vol 14 (10) ◽  
pp. 963
Author(s):  
Mayuka Tameishi ◽  
Takuro Kobori ◽  
Chihiro Tanaka ◽  
Yoko Urashima ◽  
Takuya Ito ◽  
...  

Immune checkpoint blockade (ICB) antibodies targeting programmed cell death ligand-1 (PD-L1) and programmed cell death-1 (PD-1) have improved survival in patients with conventional single agent chemotherapy-resistant gestational trophoblastic neoplasia (GTN). However, many patients are resistant to ICB therapy, the mechanisms of which are poorly understood. Unraveling the regulatory mechanism for PD-L1 expression may provide a new strategy to improve ICB therapy in patients with GTN. Here, we investigated whether the ezrin/radixin/moesin (ERM) family, i.e., a group of scaffold proteins that crosslink actin cytoskeletons with several plasma membrane proteins, plays a role in the regulation of PD-L1 expression using JEG-3 cells, a representative human choriocarcinoma cell line. Our results demonstrate mRNA and protein expressions of ezrin, radixin, and PD-L1, as well as their colocalization in the plasma membrane. Intriguingly, immunoprecipitation experiments revealed that PD-L1 interacted with both ezrin and radixin and the actin cytoskeleton. Moreover, gene silencing of ezrin but not radixin strongly diminished the cell surface expression of PD-L1 without altering the mRNA level. These results indicate that ezrin may contribute to the cell surface localization of PD-L1 as a scaffold protein in JEG-3 cells, highlighting a potential therapeutic target to improve the current ICB therapy in GTN.


Author(s):  
Lifang Zhang ◽  
Yu Zhao ◽  
Quanmei Tu ◽  
Xiangyang Xue ◽  
Xueqiong Zhu ◽  
...  

Background: Cervical cancer induced by infection with human papillomavirus (HPV) remains a leading cause of mortality for women worldwide although preventive vaccines and early diagnosis have reduced morbidity and mortality. Advanced cervical cancer can only be treated with either chemotherapy or radiotherapy but outcomes are poor. The median survival for advanced cervical cancer patients is only 16.8 months. Methods: We undertook a structural search of peer-reviewed published studies based on 1). Characteristics of programmed cell death ligand-1/programmed cell death-1(PD-L1/PD-1) expression in cervical cancer and upstream regulatory signals of PD-L1/PD-1 expression, 2). The role of the PD-L1/PD-1 axis in cervical carcinogenesis induced by HPV infection and 3). Whether the PD-L1/PD-1 axis has emerged as a potential target for cervical cancer therapies. Results: One hundred and twenty-six published papers were included in the review, demonstrating that expression of PD-L1/PD-1 is associated with HPV-caused cancer, especially with HPV 16 and 18 which account for approximately 70% of cervical cancer cases. HPV E5/E6/E7 oncogenes activate multiple signaling pathways including PI3K/AKT, MAPK, hypoxia-inducible factor 1α, STAT3/NF-kB and MicroRNAs, which regulate PD-L1/PD-1 axis to promote HPV-induced cervical carcinogenesis. The PD-L1/PD-1 axis plays a crucial role in immune escape of cervical cancer through inhibition of host immune response. creating an "immune-privileged" site for initial viral infection and subsequent adaptive immune resistance, which provides a rationale for therapeutic blockade of this axis in HPV-positive cancers. Currently, Phase I/II clinical trials evaluating the effects of PD-L1/PD-1 targeted therapies are in progress for cervical carcinoma, which provide an important opportunity for the application of anti-PD-L1/anti-PD-1 antibodies in cervical cancer treatment. Conclusion: Recent research developments have led to an entirely new class of drugs using antibodies against the PD-L1/PD-1 thus promoting the body’s immune system to fight the cancer. The expression and roles of the PD-L1/ PD-1 axis in the progression of cervical cancer provide great potential for using PD-L1/PD-1 antibodies as a targeted cancer therapy.


2021 ◽  
Vol 9 (2) ◽  
pp. e001696
Author(s):  
Yi Que ◽  
Xiao-Long Zhang ◽  
Ze-Xian Liu ◽  
Jing-Jing Zhao ◽  
Qiu-Zhong Pan ◽  
...  

BackgroundThe advent of immune checkpoint therapy has been a tremendous advance in cancer treatment. However, the responses are still insufficient in patients with soft tissue sarcoma (STS). We aimed to identify rational combinations to increase the response to immune checkpoint therapy and improve survival.MethodsWhole-exome sequencing (WES) was performed in 11 patients with liposarcoma. Somatic copy number alterations (SCNAs) were analyzed at the gene level to identify obvious amplification patterns in drug-target genes. The expression and prognostic value of class I histone deacetylases (HDACs) was evaluated in 49 patients with sarcoma in our center and confirmed in 263 sarcoma samples from The Tumor Cancer Genome Atlas (TCGA) database. Q-PCR, flow cytometry and RNA-seq were performed to determine the correlations between class I HDACs, chidamide and PD-L1 in vitro and in vivo. The efficacy of combining chidamide with PD-1 blockade was explored in an immunocompetent murine model and a small cohort of patients with advanced sarcoma. Western blot, ChIP assay and dual luciferase assessment were applied in the mechanistic study.ResultsThe HDAC gene family was frequently amplified in STS. SCNAs in the HDAC gene family were extensively amplified in 8 of 11 (73%) patients with liposarcoma, based on a drug-target gene set, and we verified amplification in 76.65% (197/257) of cases by analyzing TCGA sarcoma cohort. Class I HDAC expression is associated with a poor prognosis for patients with STS, and its inhibition is responsible for promoting apoptosis and upregulating of programmed cell death ligand 1 (PD-L1). The HDAC class I inhibitor chidamide significantly increases PD-L1 expression, increased the infiltration of CD8+ T cells and reduced the number of MDSCs in the tumor microenvironment. The combination of chidamide with an anti-PD-1 antibody significantly promotes tumor regression and improves survival in a murine model. Moreover, chidamide combined with the anti-PD-1 antibody toripalimab is effective in patients with advanced and metastatic sarcoma, and the side effects are tolerable. Mechanistically, chidamide increases histone acetylation at the PD-L1 gene through the activation of the transcriptional factor STAT1.ConclusionsThe combination of chidamide and anti-programmed cell death 1 (PD-1) therapy represents a potentially important strategy for STS.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A310-A310
Author(s):  
Krishna Gunturu ◽  
Muhammad Awidi ◽  
Rojer Ranjit ◽  
Brendan Connell ◽  
Rachel Carrasquillo ◽  
...  

BackgroundICI revolutionized modern Oncology landscape and being utilized in metastatic to adjuvant and neo-adjuvant settings. As Oncologists, we are treating cancer patients with ICI every day, yet there is still a lot that is unknown about these drugs. We don’t have clear understanding of the efficacy and toxicity when sequencing one ICI for another. We conducted a retrospective review of real world data at Lahey Hospital and Medical Center to understand further and to pave path for prospective studies to understand this issue further to improve patient care.MethodsWe retrospectively reviewed Oncology patient charts who received ICI between January1, 2014 to December 18, 2018. Total 483 patients received ICI during this time frame and 22 of these patients received a second ICI either as monotherapy or in combination with other ICI or chemotherapy.ResultsA total of 22 patients received subsequent ICI after the initial ICI as showed in table 1. 15 of the 22 (68%) patients were transitioned from one ICI to another monotherapy. 11 of these patients were transitioned secondary to disease progression (73%), three had immune related adverse events and one was switched per standard of care. One patient had ICI re-challenge. Three patients had a transition from ICI monotherapy to combination ICI therapy. One patient went onto chemo-immunotherapy and 2 patients transitioned from combination ICI to chemo-immunotherapy.Abstract 284 Table 1Real world data of sequencing immune checkpoint inhibitors (ICI) after initial ICIConclusionsICI therapy is evolving and patients are being treated with multiple lines of ICI. In current practices, ICI is frequently being transitioned from cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death 1 (PD-1) or its ligand, programmed cell death ligand 1 (PD-L1) classes or combined with chemotherapy or targeted therapy. It would be prudent to explore the effects of sequencing these medications either as a monotherapy or in combination with other therapies to better serve our patients and to prevent financial toxicity.


2021 ◽  
Vol 14 (2) ◽  
pp. 151
Author(s):  
Anica Högner ◽  
Peter Thuss-Patience

Immune checkpoint inhibitors enrich the therapeutic landscape in oesophago-gastric carcinoma. With regard to oesophageal squamous cell carcinoma (ESCC), the selective PD-1 (programmed cell death receptor 1)-inhibitor nivolumab improves disease-free survival in the adjuvant therapy setting (CHECKMATE-577). In first-line treatment, ESCC patients (pts) benefit in overall survival (OS) from the PD-1-inhibitor pembrolizumab in combination with chemotherapy (KEYNOTE-590). In the second-line setting, nivolumab (ATTRACTION-03) and pembrolizumab (KEYNOTE-181) demonstrate a benefit in OS compared with chemotherapy. These data resulted in the approval of nivolumab for the second-line treatment of advanced ESCC pts regardless of PD-L1 (programmed cell death ligand 1) status in Europe, Asia, and the USA, and pembrolizumab for pts with PD-L1 CPS (combined positivity score) ≥ 10 in Asia and the USA. Further approvals can be expected. In gastro-oesophageal junction and gastric cancer, the addition of nivolumab to chemotherapy in first-line treatment improves OS in pts with advanced disease with PD-L1 CPS ≥ 5 (CHECKMATE-649). Additionally, pembrolizumab was non-inferior to chemotherapy for OS in PD-L1 CPS ≥ 1 pts (KEYNOTE-062). In third-line treatment, nivolumab shows benefits in OS regardless of PD-L1 expression (ATTRACTION-02) with approval in Asia, and pembrolizumab prolonged the duration of response in PD-L1 positive pts (KEYNOTE-059) with approval in the USA. We discuss the recent results of the completed phase II and III clinical trials.


2021 ◽  
Vol 9 (4) ◽  
pp. 778
Author(s):  
Takayuki Murata

The immune system has evolved as a complex and efficient means of coping with extrinsic materials, such as pathogens and toxins, as well as intrinsic abnormalities, such as cancers. Although rapid and timely activation of the immune system is obviously important, regulated downregulation of the system is almost as significant as activation to prevent runaway immunity, such as allergies and hypercytokinemia. Therefore, the immune checkpoint programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway is beneficial for the host. On the other hand, pathogens have evolved to evade host immunity by taking advantage of the PD-1/PD-L1 pathway. This review is focused on human herpesviruses, such as herpes simplex virus (HSV), cytomegalovirus (CMV), and Epstein–Barr virus (EBV), which cause various types of disorders, and their relationships with the PD-1/PD-L1 pathway. Understanding such relationships will be useful for developing preventative and therapeutic methods for disorders caused by herpesviruses.


2021 ◽  
Vol 39 (15_suppl) ◽  
pp. TPS5597-TPS5597
Author(s):  
John Paul Diaz ◽  
Wenrui Duan ◽  
Eric Schroeder ◽  
Zuanel Diaz ◽  
Nicholas Lambrou ◽  
...  

TPS5597 Background: Immunotherapy has improved outcomes for patients with recurrent or metastatic cervical cancer whose tumors express PD-L1. Pembrolizumab (PEM), a monoclonal antibody that binds to programmed cell death 1 (PD 1) receptor, inhibits interaction with programmed cell death ligand 1 (PD-L1) and programmed cell death ligand 2 (PD-L2). It is approved for the treatment of recurrent or metastatic cervical cancer. Despite promising results, new strategies are being developed to improve immunotherapy responses. This includes DNA-damaging agents that have the potential to enhance the response to immunotherapy by promoting neo-antigen release, increasing tumor mutational burden, and enhancing PD-L1 expression. Poly-ADP-ribose polymerase (PARP) inhibitors, such as olaparib, have shown synergy with immunotherapy in preclinical and early clinical studies. PARP-based therapy is based on the inhibition of single-strand DNA repair, leading to DNA damage and increased tumor mutational burden. As a result, the tumor becomes a more attractive target for immunotherapy. Based on this, we are investigating the interplay between homologous recombination (HR) repair deficiency, another mechanism of DNA repair, and solid tumor response to ICI. Our approach uses an all-inclusive functional immunofluorescence assay of the Fanconi Anemia triple-staining immunofluorescence (FATSI) we developed and can be performed in paraffin-embedded tumors. Methods: This is a phase II open-label single center trial evaluating the role of PEM and olaparib in patients with metastatic cervical cancer who have progressed on first-line standard of care chemotherapy. FATSI will be performed in all patients. We hypothesize that FATSI negative tumors will be associated with improved responses. Other eligibility criteria include measurable disease by imaging, 18 years of age or older, and no previous exposure to ICI or PARP inhibitor. The primary objective is to evaluate the immune-related objective response rate (iORR) achieved in patients with FA Repair Pathway functionally competent and functionally deficient tumors. Secondary objectives include 20-week progression free survival and overall survival. Other exploratory objectives include evaluation of the mutation load and markers of neo-antigenicity, T cell receptor clonotype analyses (before and after treatment), and alterations in HR repair genes. We will utilize a two-stage phase II design to detect an iORR ≥ 20% in the whole population tested vs. the null hypothesis that the true iORR ≤5%, represents a response by chance alone or other infrequent unknown mechanisms. An interim analysis requires at least 2 of the first 20 evaluable patients enrolled have an objective response. If this occurs, we will accrue 28 additional patients to total 48. Enrollment is ongoing and two patients are currently on treatment. Clinical trial information: NCT04483544.


2018 ◽  
Vol 36 (1) ◽  
Author(s):  
Eliana La Rocca ◽  
Michela Dispinzieri ◽  
Laura Lozza ◽  
Gabriella Mariani ◽  
Serena Di Cosimo ◽  
...  

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