scholarly journals Immune Checkpoints: Therapeutic Targets for Pituitary Tumors

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Ding Nie ◽  
Yimeng Xue ◽  
Qiuyue Fang ◽  
Jianhua Cheng ◽  
Bin Li ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Antitumor Immunity ◽  
Treatment Options ◽  
Cell Activity ◽  
Pituitary Tumors ◽  
Immune Checkpoints ◽  
Intracranial Tumors ◽  
Peripheral Tissues ◽  
Effective Strategies ◽  
Immune Injury

Pituitary tumors are the third most common intracranial tumors in adults. Treatment of refractory pituitary tumors is known to be difficult due to limited treatment options. As a promising therapeutic method, tumor immunotherapy has been applied in the treatment of many tumors, including pituitary tumors. Immune checkpoint blocking is one of the effective strategies to activate antitumor immunity. Immune checkpoints prevent tissue damage by regulating the immune response of peripheral tissues and participate in the maintenance of a normal immune environment. In the presence of a tumor, inhibition of T cell activity by tumor cells binding to immune checkpoints and their ligands is an important mechanism for tumor cells to escape immune injury. In this review, we summarize the latest findings of immune checkpoints and their potential as immunotherapeutic targets for pituitary tumors.

RRx-001 is a phase III aerospace-derived small molecule that immunonormalizes the tumor microenvironment.

2019 ◽  
Vol 37 (8_suppl) ◽  
pp. 156-156
Author(s):  
Pedro Cabrales
Keyword(s):  
Tumor Microenvironment ◽  
Tumor Cells ◽  
Immune Cell ◽  
Cell Activity ◽  
Phase Iii ◽  
Cell Infiltration ◽  
Immune Checkpoints ◽  
Vascular Normalization ◽  
Tumor Associated Macrophages ◽  
Macrophage Phagocytosis

156 Background: Tumor associated macrophages (TAMs) with M2-like phenotypes produce angiogenic factors and cytokines which lead to vascular immaturity. M2 cytokines also impair immune cell activity. CD47 and SIRP⍺ are innate immune checkpoints which inhibit macrophage phagocytosis and enhance M2 polarization. Disruption of the CD47/SIRP⍺ axis polarize TAMs away from an M2-like phenotype to normalize tumor vessels and stimulate antitumor immunity. Normalized vessels facilitate delivery of drugs and immune cells and also sensitizes tumors to therapy and promotes M1-like TAM phenotype. RRx-001 modulates TAM infiltration and phenotype via CD47/SIRP⍺ downregulation, which normalizes both the tumor vasculature, and the immune cell milieu. Methods: The effect of RRx-001 on intratumoral blood flow was evaluated both preclinically and clinically with dynamic contrast MRI. An in vitro phagocytotic assay was used to determine whether RRx-001 promoted engulfment of A549 tumor cells by macrophages. Transcriptional mRNA profiling in murine tumor associated macrophages (TAMs) was performed to analyze the cytokine profile of TAMs in the presence or absence of RRx-001. Athymic mice with intracranial GBM43 were administered RRx-001 (10 mg/kg) followed 4 hours later by 0.4 mg of irinotecan by tail vein on days 12, 18, 24 and 30 after implantation of tumor cells. Mice were euthanized 24 hours after last irinotecan administration, with brains immediately resected and tumor tissue dissected prior to snap-freezing by immersion in liquid nitrogen. Results: RRx-001 was shown to induce: vascular normalization with increased intratumoral perfusion, dual downregulation of CD47 and SIRP⍺, increased phagocytosis, improved delivery of chemotherapy and increased T cell infiltration. Conclusions: RRx-001 leads to vascular normalization and enhanced delivery of chemotherapy and immune cell infiltration. The increase in tumor perfusion diminishes hypoxia and also serves to polarize TAMs away from an M2-like state. These results also suggest and are borne out by clinical biopsies that the effect of RRx-001 depends on the number of TAMs present in the tumor microenvironment with higher numbers leading to better activity.

scholarly journals The role of lncRNAs and circRNAs in the PD-1/PD-L1 pathway in cancer immunotherapy

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Wenxiao Jiang ◽  
Shuya Pan ◽  
Xin Chen ◽  
Zhi-wei Wang ◽  
Xueqiong Zhu
Keyword(s):  
Cancer Immunotherapy ◽  
Tumor Cells ◽  
Antitumor Immunity ◽  
Immune Therapy ◽  
Noncoding Rnas ◽  
Immune Checkpoints ◽  
Circular Rnas ◽  
Antitumor Effects ◽  
Antitumor Immunotherapy

AbstractCancer immunotherapy has recently shown promising antitumor effects in various types of tumors. Among all immune checkpoints, the PD-1/PD-L1 pathway plays an important role in the immune evasion of tumor cells, making it a potent target in antitumor immunity. Accordingly, antibodies targeting the PD-1/PD-L1 pathway have been developed to attack tumor cells; however, resistance to immune therapy remains to be solved. Hence, identification of the underlying modulators of the PD-1/PD-L1 pathway is of significant importance to understand the mechanisms of antitumor immunotherapy. Long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) have been identified to regulate the PD-1/PD-L1 pathway, leading to participation in the immune response and immunotherapy. Therefore, this review focuses on the functions of lncRNAs and circRNAs in regulation of the PD-1/PD-L1 axis in tumorigenesis and tumor progression. We hope this review will stimulate research to supply more precise and effective cancer immune checkpoint therapies for a large number of tumors.

A highly stable multifunctional aptamer for enhancing antitumor immunity against hepatocellular carcinoma by blocking dual immune checkpoints

2021 ◽  
Author(s):  
Yanlin Du ◽  
Da Zhang ◽  
Yiru Wang ◽  
Ming Wu ◽  
Cuilin Zhang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Immune Checkpoint ◽  
Antitumor Immunity ◽  
Immune Checkpoint Blockade ◽  
Checkpoint Blockade ◽  
Immune Checkpoints

A highly stable multifunctional aptamer was prepared for strengthening antitumor immunity through a dual immune checkpoint blockade of CTLA-4 and PD-L1.

scholarly journals Hsp70 Interacts with the TREM-1 Receptor Expressed on Monocytes and Thereby Stimulates Generation of Cytotoxic Lymphocytes Active against MHC-Negative Tumor Cells

2021 ◽  
Vol 22 (13) ◽  
pp. 6889
Author(s):  
Tatiana N. Sharapova ◽  
Elena A. Romanova ◽  
Olga K. Ivanova ◽  
Denis V. Yashin ◽  
Lidia P. Sashchenko
Keyword(s):  
Innate Immunity ◽  
Tumor Cells ◽  
Heat Shock Protein 70 ◽  
Antitumor Immunity ◽  
Lymphocyte Subpopulations ◽  
Regulatory Mechanisms ◽  
Cytotoxic Lymphocytes ◽  
Special Significance ◽  
Cytotoxic Lymphocyte ◽  
Negative Tumor

The search for and analysis of new ligands for innate immunity receptors are of special significance for understanding the regulatory mechanisms of immune response. Here we show that the major heat shock protein 70 (Hsp70) can bind to and activate TREM-1, the innate immunity receptor expressed on monocytes. The Hsp70–TREM-1 interaction activates expression of TNFα and IFNγ mRNAs in monocytes and stimulates IL-2 secretion by РВМСs. Moreover, incubation of РВМСs with Hsp70 leads to an appearance of cytotoxic lymphocyte subpopulations active against the MHC-negative tumor cells. In addition, both the CD4+ Т-lymphocytes and CD14+ monocytes are necessary for the Hsp70 signal transduction and a consequent activation of the cytotoxic lymphocytes. We believe that data presented in this study will broaden the views on the involvement of Hsp70 in the antitumor immunity.

108 MCY-M11, a CAR-PBMC cell product transiently expressing a mesothelin targeted mRNA CAR, exhibits desirable functional and immune phenotype attributed to sustained antitumor immunity in vitro

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A120-A120
Author(s):  
Sashi Kasimsetty ◽  
Himavanth Gatla ◽  
Dhana Chinnasamy
Keyword(s):  
T Cells ◽  
Tumor Cells ◽  
Antitumor Immunity ◽  
Memory T Cells ◽  
Cell Populations ◽  
Epitope Spreading ◽  
Antitumor Response ◽  
Cell Product

BackgroundMCY-M11, an anti-mesothelin CAR (Meso-CAR) mRNA transfected PBMC cell product manufactured through <1 day-process is under clinical evaluation for the treatment of advanced ovarian cancer and peritoneal mesothelioma. In this in-vitro study, we characterized the phenotypic and functional status of immune cell populations in MCY-M11 and their possible role in antitumor immunity.MethodsMCY-M11 cell product were generated using unmanipulated healthy donor PBMCs (n=5) by transfection of Meso-CAR mRNA using MaxCyte’s proprietary Flow Electroporation® system. Frozen MCY-M11 cell product was thawed and cultured for 18 hours, then co-cultured with hMSLNneg or hMSLNpos human mesothelioma cell line, MSTO-211H, or stimulated with anti-CD3/anti-CD28 antibodies in vitro for 8 days. Distinct cell populations in MCY-M11 were evaluated for kinetics and duration of CAR expression, differentiation, activation, exhaustion, and their ability to secrete various immunomodulatory molecules during in vitro stimulation. Antigen-specific proliferation and cytotoxicity of MCY-M11 against hMSLNpos tumor cells as well as their ability to mount long-term antitumor immunity through epitope spreading mechanisms were studied.ResultsIndividual cell populations in MCY-M11 exhibited a consistent but transient Meso-CAR expression persisting for about 7 days. Cell subsets in MCY-M11 acquired early signs of activation and differentiation within 18–24 hours post-culture, but only attained full activation and lineage-specific differentiation upon specific response to hMSLNpos tumor cells. hMSLN antigen experienced MCY-M11 retained significant fractions of Naïve and Central Memory T cells and increased percentage of Effector Memory T cells along with increased expression of CD62L, CD27, and chemokine receptors (CCR5, CCR7, and CXCR3). MCY-M11 exhibited strong antigen-specific cytotoxicity against hMSLNpos tumor cells with corresponding increase in activation and proliferation of CD4+ and CD8+ T cell subsets and displayed low or no acquisition of known exhaustion markers. NK cells also exhibited a functionally superior molecular signature exhibiting increased levels of NKG2D, NKp44, NKp46, FAS, and TRAIL. The Monocytes and B cells in MCY-M11 also acquired an activated, differentiated, and mature phenotype, expressing molecules required for antigen presentation (HLA-DR, HLA-ABC, and CD205) and T cell co-stimulation (CD80 and CD86) to mount a strong antitumor response. These phenotypic changes in cell subsets of MCY-M11 transpired with simultaneous secretion of potent immunostimulatory molecules and chemokines facilitating an extended antitumor response through epitope spreading.ConclusionsWe demonstrated that MCY-M11 is a unique cell product possessing a complete built-in immune cellular machinery with favorable phenotype and enhanced functions specialized in mediating an effective and long-term antitumor response.Trial RegistrationNCT03608618

scholarly journals Retargeting of NK-92 Cells against High-Risk Rhabdomyosarcomas by Means of an ERBB2 (HER2/Neu)-Specific Chimeric Antigen Receptor

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1443
Author(s):  
Leonie D. H. Gossel ◽  
Catrin Heim ◽  
Lisa-Marie Pfeffermann ◽  
Laura M. Moser ◽  
Halvard B. Bönig ◽  
...  
Keyword(s):  
High Risk ◽  
Tumor Cells ◽  
Chimeric Antigen Receptor ◽  
Treatment Options ◽  
Antigen Receptor ◽  
Proof Of Concept ◽  
Cell Monolayers ◽  
Novel Treatment ◽  
Dismal Prognosis

The dismal prognosis of pediatric and young adult patients with high-risk rhabdomyosarcoma (RMS) underscores the need for novel treatment options for this patient group. In previous studies, the tumor-associated surface antigen ERBB2 (HER2/neu) was identified as targetable in high-risk RMS. As a proof of concept, in this study, a novel treatment approach against RMS tumors using a genetically modified natural killer (NK)-92 cell line (NK-92/5.28.z) as an off-the-shelf ERBB2-chimeric antigen receptor (CAR)-engineered cell product was preclinically explored. In cytotoxicity assays, NK-92/5.28.z cells specifically recognized and efficiently eliminated RMS cell suspensions, tumor cell monolayers, and 3D tumor spheroids via the ERBB2-CAR even at effector-to-target ratios as low as 1:1. In contrast to unmodified parental NK-92 cells, which failed to lyse RMS cells, NK-92/5.28.z cells proliferated and became further activated through contact with ERBB2-positive tumor cells. Furthermore, high amounts of effector molecules, such as proinflammatory and antitumoral cytokines, were found in cocultures of NK-92/5.28.z cells with tumor cells. Taken together, our data suggest the enormous potential of this approach for improving the immunotherapy of treatment-resistant tumors, revealing the dual role of NK-92/5.28.z cells as CAR-targeted killers and modulators of endogenous adaptive immunity even in the inhibitory tumor microenvironment of high-risk RMS.

Immunotherapy for Esophageal and Gastric Cancer

2017 ◽  
pp. 292-300 ◽  
Author(s):  
Ronan J. Kelly
Keyword(s):  
Gastric Cancer ◽  
Tumor Cells ◽  
Immune Cells ◽  
Single Agent ◽  
Phase Iii ◽  
Immune Checkpoints ◽  
Barr Virus ◽  
Mutation Burden ◽  
Heavily Pretreated ◽  
Epstein Barr

PD-L1 upregulation occurs in approximately 40% of gastroesophageal cancers. However, unlike other solid tumors, there is minimal PD-L1 expressed on the cancer cells; rather, expression occurs predominantly on infiltrating myeloid cells. Preliminary clinical data involving single-agent PD-1/PD-L1 inhibitors in metastatic gastroesophageal cancer have reported response rates of 22%–27% for patients with PD-L1+ tumors and 10%–17% for unselected patients. The phase III ONO-4538-12 (ATTRACTION 2) trial has demonstrated an improved overall survival for nivolumab compared with placebo for patients with heavily pretreated gastric cancer. In the future, we will need better biomarkers to select those most likely to respond and/or identify patients who may need combination immunotherapeutics or alternate strategies. A number of subsets of gastric cancer with different immune signatures, most notably tumors positive for Epstein-Barr virus and microsatellite instability, have been identified, with approximately 50% and 94% PD-L1+ staining seen on tumor cells and immune cells in the EBV subtype and approximately 33% and 45% PD-L1+ staining seen on tumor cells and immune cells in MSI high tumors. Both subtypes demonstrate PD-L1+ immune cells with tumor-infiltrating patterns, unlike the more commonly seen PD-L1+ immune cells at the invasive margin. PD-L2 expression has been reported in 52% of esophageal adenocarcinomas but little is known about the expression of other immune checkpoints. Additional factors that suggest gastroesophageal cancers may respond to checkpoint inhibition include the high somatic mutation burden and the link with chronic inflammation. Here we provide a comprehensive review of the checkpoint inhibitor data published to date in advanced esophagogastric cancers and rationalize how the immune microenvironment in these diverse tumors can explain response or resistance to immunotherapeutics.

Formalin-fixed tumor cells effectively induce antitumor immunity both in prophylactic and therapeutic conditions

2004 ◽  
Vol 34 (3) ◽  
pp. 209-219 ◽  
Author(s):  
Chikage Obata ◽  
Manxin Zhang ◽  
Yoichi Moroi ◽  
Hajime Hisaeda ◽  
Keiji Tanaka ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Antitumor Immunity ◽  
Formalin Fixed ◽  
Fixed Tumor

The deposition of Hg203-chlormerodrin in experimental brain tumors

1971 ◽  
Vol 35 (3) ◽  
pp. 303-308 ◽  
Author(s):  
Tatsuya Kobayashi ◽  
Louis Bakay ◽  
Joseph C. Lee
Keyword(s):  
Brain Tumors ◽  
Tumor Cells ◽  
Normal Brain ◽  
Intracranial Tumors ◽  
Electron Microscopic ◽  
Electron Microscopic Autoradiography ◽  
Content Type ◽  
Meningeal Tumors ◽  
Vacuolar System ◽  
Fine Print

✓ The deposition of Hg203-chlormerodrin was studied in intracranial tumors in mice induced by implantation of 20-methyl cholanthrene by tissue assay, as well as light microscopic and electron microscopic autoradiography. The investigations were carried out in astrocytomas, glioblastomas, and meningeal tumors. The chlormerodrin content of the tumors exceeded that of normal brain with a significant tumor/brain ratio ranging from 5.8 to 22.5. It was found that the chlormerodrin molecule becomes rapidly incorporated in the tumor cells, with a preference for that portion of the cytoplasm associated with the vacuolar system.

Dual angiopoietin-2 and VEGFA inhibition elicits antitumor immunity that is enhanced by PD-1 checkpoint blockade

2017 ◽  
Vol 9 (385) ◽  
pp. eaak9670 ◽  
Author(s):  
Martina Schmittnaegel ◽  
Nicolò Rigamonti ◽  
Ece Kadioglu ◽  
Antonino Cassará ◽  
Céline Wyser Rmili ◽  
...  
Keyword(s):  
Antitumor Immunity ◽  
Antiangiogenic Therapy ◽  
Metastatic Breast ◽  
Pancreatic Neuroendocrine Tumor ◽  
Genetically Engineered ◽  
Immune Checkpoints ◽  
Tumor Control ◽  
Antitumoral Activity ◽  
Therapeutic Benefits ◽  
Angiopoietin 2

Pathological angiogenesis is a hallmark of cancer and a therapeutic target. Vascular endothelial growth factor A (VEGFA) and angiopoietin-2 (ANGPT2; also known as ANG2) are proangiogenic cytokines that sustain tumor angiogenesis and limit antitumor immunity. We show that combined ANGPT2 and VEGFA blockade by a bispecific antibody (A2V) provided superior therapeutic benefits, as compared to the single agents, in both genetically engineered and transplant tumor models, including metastatic breast cancer (MMTV-PyMT), pancreatic neuroendocrine tumor (RIP1-Tag2), and melanoma. Mechanistically, A2V promoted vascular regression, tumor necrosis, and antigen presentation by intratumoral phagocytes. A2V also normalized the remaining blood vessels and facilitated the extravasation and perivascular accumulation of activated, interferon-γ (IFNγ)–expressing CD8+ cytotoxic T lymphocytes (CTLs). Whereas the antitumoral activity of A2V was, at least partly, CTL-dependent, perivascular T cells concurrently up-regulated the expression of the immune checkpoint ligand programmed cell death ligand 1 (PD-L1) in tumor endothelial cells. IFNγ neutralization blunted this adaptive response, and PD-1 blockade improved tumor control by A2V in different cancer models. These findings position immune cells as key effectors of antiangiogenic therapy and support the rationale for cotargeting angiogenesis and immune checkpoints in cancer therapy.

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