scholarly journals Tumor PD-L1 Induction by Resveratrol/Piceatannol May Function as a Search, Enhance, and Engage (“SEE”) Signal to Facilitate the Elimination of “Cold, Non-Responsive” Low PD-L1-Expressing Tumors by PD-L1 Blockade

2019 ◽  
Vol 20 (23) ◽  
pp. 5969 ◽  
Author(s):  
Tze-Chen Hsieh ◽  
Joseph M. Wu
Keyword(s):  
Cell Death ◽  
Antitumor Activity ◽  
Programmed Cell Death ◽  
Selection Criteria ◽  
Regulatory Protein ◽  
Immune Surveillance ◽  
Tumor Escape ◽  
Free Response ◽  
High Level ◽  
Host Immune Surveillance

Programmed cell death ligand 1 (PD-L1) is an immune regulatory protein that facilitates tumor escape from host immune surveillance. In the clinic, tumors with high level of PD-L1 have been used to identify patients who might respond favorably to treatment by anti-PD-L1 antibodies (PD-L1 blockade, PLB). Typically, a progression-free response of 9–20% to PLB has been observed, the basis for the low success rate is largely unknown. Recently, we show upregulation of PD-L1 in cancer cells by ≥IC50 supra-pharmacological dose of grape polyphenol resveratrol and piceatannol, alone and combined. Herein, we summarize recent published studies on the regulation of tumor PD-L1 by flavonoids and grape polyphenols. We hypothesize that the induced tumor PD-L1 by resveratrol and/or piceatannol may serve as a Search, Enhance, and Engage (“SEE”) signal to sensitize and augment the recognition and detection of low PD-L1-expressing “cold, non-responsive” tumors. The “SEE” strategy enhances the “visibility” of previously unidentified tumor cells for targeting and eventual eradication by the host antitumor activity. This strategy expands the selection criteria for patients with improved sensitivity and potential responsiveness when used in combination with PLB. The modulation of tumor PD-L1 by flavonoids or polyphenols is proposed to improve the response to PLB in low PD-L1 tumors.

scholarly journals Response to Comment on “Sterilizing immunity in the lung relies on targeting fungal apoptosis-like programmed cell death”

Science ◽  
2018 ◽  
Vol 360 (6395) ◽  
pp. eaas9457
Author(s):  
Neta Shlezinger ◽  
Henriette Irmer ◽  
Sourabh Dhingra ◽  
Sarah R. Beattie ◽  
Robert A. Cramer ◽  
...  
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Aspergillus Fumigatus ◽  
Experimental Approach ◽  
Immune Surveillance ◽  
Genetic Manipulations ◽  
Sterilizing Immunity ◽  
Single Approach ◽  
Host Immune Surveillance

Aouacheria et al. question the interpretation of contemporary assays to monitor programmed cell death with apoptosis-like features (A-PCD) in Aspergillus fumigatus. Although our study focuses on fungal A-PCD for host immune surveillance and infectious outcomes, the experimental approach incorporates multiple independent A-PCD markers and genetic manipulations based on fungal rather than mammalian orthologs to circumvent the limitations associated with any single approach.

Stem cell factor and leukemia inhibitory factor promote primordial germ cell survival by suppressing programmed cell death (apoptosis)

Development ◽  
1993 ◽  
Vol 118 (4) ◽  
pp. 1089-1094 ◽  
Author(s):  
M. Pesce ◽  
M.G. Farrace ◽  
M. Piacentini ◽  
S. Dolci ◽  
M. De Felici
Keyword(s):  
Cell Death ◽  
Stem Cell ◽  
Programmed Cell Death ◽  
Leukemia Inhibitory Factor ◽  
Stem Cell Factor ◽  
Tissue Transglutaminase ◽  
Primordial Germ Cell ◽  
Inhibitory Factor ◽  
High Level

Proliferating primordial germ cells (PGCs) isolated from mouse embryos soon after their arrival in the genital ridges would only survive in vitro at temperature of less than 30 degrees C (De Felici, M. and McLaren, A. (1983). Exp. Cell. Res. 144, 417–427; Wabik-Sliz, B. and McLaren, A. (1984). Exp. Cell. Res. 154, 530–536) or when co-cultured on cell feeder layers (Donovan, P. J., Stott, D., Godin, I., Heasman, J. and Wylie, C. C. (1986). Cell 44, 831–838; De Felici, M. and Dolci, S. (1991). Dev. Biol. 147, 281–284). In the present paper we report that mouse PGC death in vitro occurs with all the hallmarks of programmed cell death or apoptosis. We found that after 4–5 hours in culture many PGCs isolated from 12.5 dpc fetal gonads assumed a nuclear morphology and produced membrane bound fragments (apoptotic bodies) typical of apoptotic cells. In addition, PGCs in culture accumulated high level of tissue transglutaminase (tTGase; an enzyme that is induced and activated during apoptosis) and showed extensive degradation of DNA to oligonucleosomal fragments, which is characteristic of apoptosis. The physiological relevance of this mechanism of PGC death is supported by the finding that some PGCs undergoing apoptosis, as revealed by the high level of tTGase expression, were detected in the embryo. Most importantly, we show that the addition of stem cell factor (SCF) or leukemia inhibitory factor (LIF) to the culture medium, two cytokines known to favour PGC survival and/or proliferation in vitro, markedly reduced the occurrence of apoptosis in PGCs during the first hours in culture.(ABSTRACT TRUNCATED AT 250 WORDS)

PD-L1 is induced on the hepatocyte surface via CKLF-like MARVEL transmembrane domain-containing protein 6 up-regulation by the anti-HBV drug Entecavir

2020 ◽  
Vol 32 (8) ◽  
pp. 519-531 ◽  
Author(s):  
Yuichiro Yamamoto ◽  
Masatoshi Kakizaki ◽  
Takayuki Shimizu ◽  
Joaquim Carreras ◽  
Tetsuhiro Chiba ◽  
...  
Keyword(s):  
Cell Death ◽  
Hepatitis B ◽  
Programmed Cell Death ◽  
Cell Surface ◽  
Transmembrane Domain ◽  
Immune Surveillance ◽  
Hbv Infection ◽  
Jurkat Cells ◽  
Hbv Replication ◽  
Checkpoint Molecule

Abstract Chronic hepatitis B is now controllable when treated with nucleoside reverse transcriptase inhibitors (NRTIs), which inhibit hepatitis B virus (HBV) replication. However, once the NRTIs are discontinued, most patients relapse, necessitating lifelong NRTIs treatment. HBV infection relapse is assumed to be caused by the persistent existence of covalently closed circular DNA (cccDNA) in the nuclei of infected hepatocytes. The mechanism by which cccDNA-positive hepatocytes escape immune surveillance during NRTIs treatment remains elusive. Entecavir (ETV), a commonly used NRTI, post-transcriptionally up-regulates programmed cell death-ligand 1 (PD-L1), an immune checkpoint molecule, on the cell surface of hepatocytes regardless of HBV infection. Up-regulation by ETV depends on up-regulation of CKLF-like MARVEL transmembrane domain-containing 6, a newly identified potent regulator of PD-L1 expression on the cell surface. ETV-treated hepatic cells suppressed the activity of primary CD3 T cells and programmed cell death protein-1 (PD-1)-over-expressed Jurkat cells. Finally, ETV induces PD-L1 in primary hepatocytes infected by HBV. These results provide evidence that ETV considerably up-regulates PD-L1 on the cell surface of infected hepatocytes, which may be one of the mechanisms by which infected hepatocytes subvert immune surveillance.

scholarly journals Tislelizumab in Chinese patients with advanced solid tumors: an open-label, non-comparative, phase 1/2 study

2020 ◽  
Vol 8 (1) ◽  
pp. e000437
Author(s):  
Lin Shen ◽  
Jun Guo ◽  
Qingyuan Zhang ◽  
Hongming Pan ◽  
Ying Yuan ◽  
...  
Keyword(s):  
Cell Death ◽  
Antitumor Activity ◽  
Programmed Cell Death ◽  
Solid Tumors ◽  
Phase 1 ◽  
Chinese Patients ◽  
Advanced Solid Tumors ◽  
Phase 2 ◽  
Dose Verification ◽  
Open Label

BackgroundTislelizumab is an investigational, humanized, IgG4 monoclonal antibody with high affinity and binding specificity for programmed cell death-1 (PD-1) that was engineered to minimize binding to FcγR on macrophages in order to abrogate antibody-dependent phagocytosis, a mechanism of T-cell clearance and potential resistance to anti-PD-1 therapy.MethodsThe purpose of this phase 1/2, open-label, non-comparative study was to examine the safety, tolerability, and antitumor activity of tislelizumab in adult (≥18 years) Chinese patients with histologically or cytologically confirmed advanced solid tumors with measurable disease. The phase 1 portion of the study consisted of a dose-verification study and a pharmacokinetic (PK) substudy; phase 2 was an indication-expansion study including 11 solid tumor cohorts. Patients previously treated with therapies targeting PD-1 or its ligand, programmed cell death ligand-1 were excluded. During dose-verification, dose-limiting toxicities (DLTs) were monitored; safety and tolerability were examined and the previously determined recommended phase 2 dose (RP2D) was verified. The primary endpoint of phase 2 was investigator-assessed objective response rate per Response Evaluation Criteria in Solid Tumors V.1.1.ResultsAs of December 1, 2018, 300 patients were treated with tislelizumab 200 mg intravenously once every 3 weeks (Q3W). Median duration of follow-up was 8.1 months (range 0.2–21.9). No DLTs were reported during the phase 1 dose-verification study and the RP2D was confirmed to be 200 mg intravenously Q3W. Most treatment-related adverse events (62%) were grade 1 or 2, with the most common being anemia (n=70; 23%) and increased aspartate aminotransferase (n=67; 22%). Of the 251 efficacy evaluable patients, 45 (18%) achieved a confirmed clinical response, including one patient from the PK substudy who achieved a complete response. Median duration of response was not reached for all except the nasopharyngeal carcinoma cohort (8.3 months). Antitumor responses were observed in multiple tumor types.ConclusionsTislelizumab was generally well tolerated among Chinese patients. Antitumor activity was observed in patients with multiple solid tumors.Trial registration numberCTR20160872.

scholarly journals Selective Suppression of Cell Growth and Programmed Cell Death-Ligand 1 Expression in HT1080 Fibrosarcoma Cells by Low Molecular Weight Fucoidan Extract

Marine Drugs ◽  
2019 ◽  
Vol 17 (7) ◽  
pp. 421 ◽  
Author(s):  
Kiichiro Teruya ◽  
Yoshihiro Kusumoto ◽  
Hiroshi Eto ◽  
Noboru Nakamichi ◽  
Sanetaka Shirahata
Keyword(s):  
Molecular Weight ◽  
Cell Death ◽  
Programmed Cell Death ◽  
Cancer Cells ◽  
Biological Activities ◽  
Immune Surveillance ◽  
Selective Inhibition ◽  
Low Molecular Weight ◽  
Fibrosarcoma Cells ◽  
Self Protection

Low molecular weight fucoidan extract (LMF), prepared by an abalone glycosidase digestion of a crude fucoidan extracted from Cladosiphon novae-caledoniae Kylin, exhibits various biological activities, including anticancer effect. Various cancers express programmed cell death-ligand 1 (PD-L1), which is known to play a significant role in evasion of the host immune surveillance system. PD-L1 is also expressed in many types of normal cells for self-protection. Previous research has revealed that selective inhibition of PD-L1 expressed in cancer cells is critical for successful cancer eradication. In the present study, we analyzed whether LMF could regulate PD-L1 expression in HT1080 fibrosarcoma cells. Our results demonstrated that LMF suppressed PD-L1/PD-L2 expression and the growth of HT1080 cancer cells and had no effect on the growth of normal TIG-1 cells. Thus, LMF differentially regulates PD-L1 expression in normal and cancer cells and could serve as an alternative complementary agent for treatment of cancers with high PD-L1 expression.

scholarly journals Macrophages eat cancer cells using their own calreticulin as a guide: Roles of TLR and Btk

2015 ◽  
Vol 112 (7) ◽  
pp. 2145-2150 ◽  
Author(s):  
Mingye Feng ◽  
James Y. Chen ◽  
Rachel Weissman-Tsukamoto ◽  
Jens-Peter Volkmer ◽  
Po Yi Ho ◽  
...  
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Cell Surface ◽  
Tyrosine Kinase ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Regulatory Protein ◽  
Toll Like Receptor ◽  
Tlr Signaling ◽  
Target Cancer

Macrophage-mediated programmed cell removal (PrCR) is an important mechanism of eliminating diseased and damaged cells before programmed cell death. The induction of PrCR by eat-me signals on tumor cells is countered by don’t-eat-me signals such as CD47, which binds macrophage signal-regulatory protein α to inhibit phagocytosis. Blockade of CD47 on tumor cells leads to phagocytosis by macrophages. Here we demonstrate that the activation of Toll-like receptor (TLR) signaling pathways in macrophages synergizes with blocking CD47 on tumor cells to enhance PrCR. Bruton’s tyrosine kinase (Btk) mediates TLR signaling in macrophages. Calreticulin, previously shown to be an eat-me signal on cancer cells, is activated in macrophages for secretion and cell-surface exposure by TLR and Btk to target cancer cells for phagocytosis, even if the cancer cells themselves do not express calreticulin.

scholarly journals The Role of Oncogenes and Redox Signaling in the Regulation of PD-L1 in Cancer

Cancers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 4426
Author(s):  
Christophe Glorieux ◽  
Xiaojun Xia ◽  
Peng Huang
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Cell Function ◽  
Immune Surveillance ◽  
Redox Signaling ◽  
Checkpoint Signaling ◽  
Therapeutic Implications ◽  
Programmed Cell Death 1 ◽  
Control Tumor

Tumor cells can evade the immune system via multiple mechanisms, including the dysregulation of the immune checkpoint signaling. These signaling molecules are important factors that can either stimulate or inhibit tumor immune response. Under normal physiological conditions, the interaction between programmed cell death ligand 1 (PD-L1) and its receptor, programmed cell death 1 (PD-1), negatively regulates T cell function. In cancer cells, high expression of PD-L1 plays a key role in cancer evasion of the immune surveillance and seems to be correlated with clinical response to immunotherapy. As such, it is important to understand various mechanisms by which PD-L1 is regulated. In this review article, we provide an up-to-date review of the different mechanisms that regulate PD-L1 expression in cancer. We will focus on the roles of oncogenic signals (c-Myc, EML4-ALK, K-ras and p53 mutants), growth factor receptors (EGFR and FGFR), and redox signaling in the regulation of PD-L1 expression and discuss their clinical relevance and therapeutic implications. These oncogenic signalings have common and distinct regulatory mechanisms and can also cooperatively control tumor PD-L1 expression. Finally, strategies to target PD-L1 expression in tumor microenvironment including combination therapies will be also discussed.

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