Immune checkpoint and checkpoint inhibitors in hepatocellular carcinoma

2018 ◽  
Vol 1 (1) ◽  
pp. 28-32
Author(s):  
Piyawat Komolmit

การรักษามะเร็งด้วยแนวความคิดของการกระตุ้นให้ภูมิต้านทานของร่างกายไปทำลายเซลล์มะเร็งนั้น ปัจจุบันได้รับการพิสูจน์ชัดว่าวิธีการนี้สามารถหยุดยั้งการแพร่กระจายของเซลล์มะเร็ง โดยไม่ก่อให้เกิดภาวะแทรกซ้อนทางปฏิกิริยาภูมิต้านทานต่ออวัยวะส่วนอื่นที่รุนแรง สามารถนำมาใช้ทางคลินิกได้ ยุคของการรักษามะเร็งกำลังเปลี่ยนจากยุคของยาเคมีบำบัดเข้าสู่การรักษาด้วยภูมิต้านทาน หรือ immunotherapy ยากลุ่ม Immune checkpoint inhibitors โดยเฉพาะ PD-1 กับ CTLA-4 inhibitors จะเข้ามามีบทบาทในการรักษามะเร็งตับในระยะเวลาอันใกล้ จำเป็นแพทย์จะต้องมีความรู้ความเข้าใจในพื้นฐานของ immune checkpoints และยาที่ไปยับยั้งโมเลกุลเหล่านี้ Figure 1 เมื่อ T cells รับรู้แอนทิเจนผ่านทาง TCR/MHC จะมีปฏิกิริยาระหว่าง co-receptors หรือ immune checkpoints กับ ligands บน APCs หรือ เซลล์มะเร็ง ทั้งแบบกระตุ้น (co-stimulation) หรือยับยั้ง (co-inhibition) TCR = T cell receptor, MHC = major histocompatibility complex

Cancers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1689 ◽  
Author(s):  
Edoardo Giannini ◽  
Andrea Aglitti ◽  
Mauro Borzio ◽  
Martina Gambato ◽  
Maria Guarino ◽  
...  

Despite progress in our understanding of the biology of hepatocellular carcinoma (HCC), this tumour remains difficult-to-cure for several reasons, starting from the particular disease environment where it arises—advanced chronic liver disease—to its heterogeneous clinical and biological behaviour. The advent, and good results, of immunotherapy for cancer called for the evaluation of its potential application also in HCC, where there is evidence of intra-hepatic immune response activation. Several studies advanced our knowledge of immune checkpoints expression in HCC, thus suggesting that immune checkpoint blockade may have a strong rationale even in the treatment of HCC. According to this background, initial studies with tremelimumab, a cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitor, and nivolumab, a programmed cell death protein 1 (PD-1) antibody, showed promising results, and further studies exploring the effects of other immune checkpoint inhibitors, alone or with other drugs, are currently underway. However, we are still far from the identification of the correct setting, and sequence, where these drugs might be used in clinical practice, and their actual applicability in real-life is unknown. This review focuses on HCC immunobiology and on the potential of immune checkpoint blockade therapy for this tumour, with a critical evaluation of the available trials on immune checkpoint blocking antibodies treatment for HCC. Moreover, it assesses the potential applicability of immune checkpoint inhibitors in the real-life setting, by analysing a large, multicentre cohort of Italian patients with HCC.


1993 ◽  
Vol 177 (6) ◽  
pp. 1541-1550 ◽  
Author(s):  
S C Jameson ◽  
F R Carbone ◽  
M J Bevan

A previous report showed that the proliferative response of helper T cells to class II major histocompatibility complex (MHC)-restricted antigens can be inhibited by analogues of the antigen, which act as T cell receptor (TCR) antagonists. Here we define and analyze peptide variants that antagonize various functions of class I MHC-restricted cytotoxic T lymphocyte (CTL) clones. Of 64 variants at individual TCR contact sites of the Kb-restricted octamer peptide ovalbumin257-264 (OVAp), a very high proportion (40%) antagonized lysis by three OVAp-specific CTL clones. This effect was highly clone specific, since many antagonists for one T cell clone have differential effects on another. We show that this inhibition of CTL function is not a result of T cell-T cell interaction, precluding veto-like phenomena as a mechanism for antagonism. Moreover, we present evidence for direct interaction between the TCR and antagonist-MHC complexes. In further analysis of the T cell response, we found that serine esterase release and cytokine production are susceptible to TCR antagonism similarly to lysis. Ca2+ flux, an early event in signaling, is also inhibited by antagonists but may be more resistant to the antagonist effect than downstream responses.


Nature ◽  
1988 ◽  
Vol 335 (6187) ◽  
pp. 229-233 ◽  
Author(s):  
Hung Sia Teh ◽  
Pawel Kisielow ◽  
Bernadette Scott ◽  
Hiroyuki Kishi ◽  
Yasushi Uematsu ◽  
...  

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Takayoshi Yamauchi ◽  
Toshifumi Hoki ◽  
Takaaki Oba ◽  
Vaibhav Jain ◽  
Hongbin Chen ◽  
...  

AbstractImmune checkpoint inhibitors (ICI) have revolutionized treatment for various cancers; however, durable response is limited to only a subset of patients. Discovery of blood-based biomarkers that reflect dynamic change of the tumor microenvironment, and predict response to ICI, will markedly improve current treatment regimens. Here, we investigate CX3C chemokine receptor 1 (CX3CR1), a marker of T-cell differentiation, as a predictive correlate of response to ICI therapy. Successful treatment of tumor-bearing mice with ICI increases the frequency and T-cell receptor clonality of the peripheral CX3CR1+CD8+ T-cell subset that includes an enriched repertoire of tumor-specific and tumor-infiltrating CD8+ T cells. Furthermore, an increase in the frequency of the CX3CR1+ subset in circulating CD8+ T cells early after initiation of anti-PD-1 therapy correlates with response and survival in patients with non-small cell lung cancer. Collectively, these data support T-cell CX3CR1 expression as a blood-based dynamic early on-treatment predictor of response to ICI therapy.


1994 ◽  
Vol 180 (5) ◽  
pp. 1921-1929 ◽  
Author(s):  
N Labrecque ◽  
J Thibodeau ◽  
W Mourad ◽  
R P Sékaly

Bacterial and retroviral superantigens (SAGs) stimulate a high proportion of T cells expressing specific variable regions of the T cell receptor (TCR) beta chain. Although most alleles and isotypes bind SAGs, polymorphisms of major histocompatibility complex (MHC) class II molecules affect their presentation to T cells. This observation has raised the possibility that a TCR-MHC class II interaction can occur during this recognition process. To address the importance of such interactions during SAG presentation, we have used a panel of murine T cell hybridomas that respond to the bacterial SAG Staphylococcal enterotoxin B (SEB) and to the retroviral SAG Mtv-7 when presented by antigen-presenting cells (APCs) expressing HLA-DR1. Amino acid substitutions of the putative TCR contact residues 59, 64, 66, 77, and 81 on the DR1 beta chain showed that these amino acids are critical for recognition of the SAG SEB by T cells. TCR-MHC class II interactions are thus required for T cell recognition of SAG. Moreover, Mtv-7 SAG recognition by the same T cell hybridomas was not affected by these mutations, suggesting that the topology of the TCR-MHC class II-SAG trimolecular complex could be different from one TCR to another and from one SAG to another.


1997 ◽  
Vol 186 (8) ◽  
pp. 1269-1275 ◽  
Author(s):  
Jörg Kirberg ◽  
Anton Berns ◽  
Harald von Boehmer

In the thymus, T cells are selected according to their T cell receptor (TCR) specificity. After positive selection, mature cells are exported from primary lymphoid organs to seed the secondary lymphoid tissue. An important question is whether survival of mature T cells is an intrinsic property or requires continuous survival signals, i.e., engagement of the TCR by major histocompatibility complex (MHC) molecules in the periphery, perhaps in a similar way as occurring during thymic positive selection. To address this issue we used recombination-activating gene (Rag)-deficient H-2b mice expressing a transgenic TCR restricted by I-Ed class II MHC molecules. After engraftment with Rag−/− H-2d fetal thymi, CD4+8− peripheral T cells emerged. These cells were isolated and transferred into immunodeficient hosts of H-2b or H-2d haplotype, some of the latter being common cytokine receptor γ chain deficient to exclude rejection of H-2b donor cells by host natural killer cells. Our results show that in the absence, but not in the presence, of selecting MHC molecules, peripheral mature T cells are short lived and disappear within 7 wk, indicating that continuous contact of the TCR with selecting MHC molecules is required for survival of T cells.


Author(s):  
Eiji Nakata ◽  
Tomohiro Fujiwara ◽  
Toshiyuki Kunisada ◽  
Tastuo Ito ◽  
Shota Takihira ◽  
...  

Abstract Sarcomas are a heterogeneous group of malignancies of mesenchymal origin; their molecular and genomic mechanisms differ with regard to histology. These characteristics lead to the presentation of varied immunological profiles based on the tumor microenvironment. Various immunotherapies are considered for the treatment of sarcoma. These treatments are performed either in isolation or in combination with other methods such as cytotoxic chemotherapy or the use of molecular target agents. Among these, two recently emerging immunotherapies include T-cell receptor gene therapy and immune checkpoint inhibitor therapy, which are expected to be effective for many types of sarcoma. A sarcoma with a disease-specific translocation and a limited number of mutations, such as synovial sarcoma, expresses high levels of self-antigens, like the New York esophageal squamous cell carcinoma 1, which has been targeted in T-cell receptor gene therapy. On the other hand, sarcomas with a greater number of mutations, such as undifferentiated pleomorphic sarcomas, myxofibrosarcoma and dedifferentiated liposarcomas, can be good candidates for immune checkpoint inhibitors. Among immune checkpoint inhibitor therapies, programmed cell death-1 blockade (nivolumab and pembrolizumab) and cytotoxic T-lymphocyte–associated antigen 4 blockade (ipilimumab) have been investigated most often in sarcoma. Although the sole use of immune checkpoint inhibitors provides limited efficacy, combined immunotherapy with immune checkpoint inhibitors or molecular target agents, especially antiangiogenic agents, has shown moderate results against some types of sarcoma, such as the alveolar soft part sarcoma. Several clinical trials utilizing immunotherapy, including T-cell receptor gene therapy and immune checkpoint inhibitors, in sarcomas are under progress. By clarifying the tumor microenvironment and biomarker-predictive capacity of immunotherapy in sarcomas, better clinical trials can be designed; this could lead to improved outcomes for immunotherapy in sarcoma.


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