scholarly journals Analysis of the immune landscape of small bowel neuroendocrine tumors

2019 ◽  
Vol 26 (1) ◽  
pp. 119-130 ◽  
Author(s):  
M Cives ◽  
J Strosberg ◽  
S Al Diffalha ◽  
D Coppola

Immune checkpoint inhibitors have shown promising results in different cancers, and correlation between immune infiltration, expression of programmed death-ligand 1 (PD-L1) by tumor cells and response to immunotherapy has been reported. There is limited knowledge regarding the immune microenvironment of small bowel (SB) neuroendocrine tumors (NETs). This work was aimed at characterizing the immune landscape of SB NETs. Expression of PD-L1 and programmed death-1 (PD-1) was evaluated by immunohistochemistry in 102 surgically resected, primary NETs of the duodenum, jejunum and ileum. Extent and characteristics of the tumor-associated immune infiltrate were also assessed and investigated in their prognostic potential. We detected the expression of PD-L1 in ≥1 and ≥50% of tumor cells in 40/102 (39%; 95% CI, 30–49%) and 14/102 (14%; 95% CI, 8–22%) cases respectively. Intratumor host immune response was apparently absent in 35/102 cases (34%; 95% CI, 25–44%), mild to moderate in 46/102 samples (45%, 95% CI, 35–55%), intense in 21/102 tumors (21%, 95% CI, 13–30%). Expression of PD-L1 and extent of immune infiltration were significantly higher in duodenal NETs as compared with jejunal/ileal NETs. A marked peritumoral host response was organized as ectopic lymph node-like structures in 18/102 cases (18%; 95% CI, 11–26%). Neither PD-L1 expression nor the degree of immune infiltration showed any prognostic significance. Overall, the immune landscape of SB NETs is heterogeneous, with adaptive immune resistance mechanisms prevailing in duodenal NETs. Clinical trials of immune checkpoint inhibitors should take into account the immune heterogeneity of SB NETs.

Author(s):  
Revati Sharma ◽  
Elif Kadife ◽  
Mark Myers ◽  
George Kannourakis ◽  
Prashanth Prithviraj ◽  
...  

AbstractVascular endothelial growth factor tyrosine kinase inhibitors (VEGF-TKIs) have been the mainstay of treatment for patients with advanced renal cell carcinoma (RCC). Despite its early promising results in decreasing or delaying the progression of RCC in patients, VEGF-TKIs have provided modest benefits in terms of disease-free progression, as 70% of the patients who initially respond to the treatment later develop drug resistance, with 30% of the patients innately resistant to VEGF-TKIs. In the past decade, several molecular and genetic mechanisms of VEGF-TKI resistance have been reported. One of the mechanisms of VEGF-TKIs is inhibition of the classical angiogenesis pathway. However, recent studies have shown the restoration of an alternative angiogenesis pathway in modulating resistance. Further, in the last 5 years, immune checkpoint inhibitors (ICIs) have revolutionized RCC treatment. Although some patients exhibit potent responses, a non-negligible number of patients are innately resistant or develop resistance within a few months to ICI therapy. Hence, an understanding of the mechanisms of VEGF-TKI and ICI resistance will help in formulating useful knowledge about developing effective treatment strategies for patients with advanced RCC. In this article, we review recent findings on the emerging understanding of RCC pathology, VEGF-TKI and ICI resistance mechanisms, and potential avenues to overcome these resistance mechanisms through rationally designed combination therapies.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi93-vi93
Author(s):  
Stephanie Sanders ◽  
Denise Herpai ◽  
Waldemar Debinski

Abstract Glioblastoma (GBM) is an immunologically cold tumor. Using single cell sequencing of CD45+ cells we confirmed that T cells are present within GBM samples. These T cells are positive for exhaustion markers such as LAG3 and TIGIT, as well as CTLA4 and PD1 checkpoint receptors. Modulating T cell activity through use of immune checkpoint inhibitors (ICIs) has shown efficacy in the treatment of a variety of solid tumors, and the combination of anti-CTLA4 and anti-PD1 ICIs has shown increased efficacy over use of a single therapeutic. Additionally, targeting ICIs to the tumor cells may increase efficacy of this treatment. We therefore constructed a combinatorial ICI redirected to GBM via interleukin 13 receptor alpha 2 (IL13RA2), a receptor over-expressed on the majority of GBM cells but not normal brain. The first component of the construct, labeled with a histidine tag, targets CTLA4 while the second component, tagged with a StrepII tag, targets PD1. The tags added to the constructs will allow for purification of a combinatorial heterodimer simultaneously targeting PD1, CTLA4 and IL13RA2. We purified individual components via fast protein liquid chromatography (FPLC) using a proteinG column followed by a HisTrap or StrepTrap column. We obtained a recombinant, targeted multivalent ICI at > 95% purity. We found that these constructs are able to bind their target receptors via ELISA in which the Kd values ranged from picomolar to low nanomolar range. Additionally, our constructs bind their target on live cells by flow cytometry. We next designed a heterodimeric construct which can combinatorially target CTLA4 and PD1 while also directing the ICI therapy to GBM. These constructs in conjunction with other immune stimulants like cytotoxic therapies are intended to facilitate the interaction between T cells and GBM tumor cells directly in a tumor microenvironment.


Oncotarget ◽  
2017 ◽  
Vol 9 (10) ◽  
pp. 8801-8809 ◽  
Author(s):  
Aman Chauhan ◽  
Millicent Horn ◽  
Gray Magee ◽  
Kurt Hodges ◽  
Mark Evers ◽  
...  

Immunotherapy ◽  
2021 ◽  
Author(s):  
Fausto Petrelli ◽  
Roberto Ferrara ◽  
Diego Signorelli ◽  
Antonio Ghidini ◽  
Claudia Proto ◽  
...  

This study is a meta-analysis of randomized controlled trials involving first-line studies in which immune checkpoint inhibitors were added to chemotherapy and were compared with chemotherapy alone. The primary end point was overall survival (OS). The analyses used random-effects models and the Grading of Recommendations Assessment, Development, and Evaluation system to rate the quality of the evidence. Nine articles were included for qualitative and quantitative synthesis. A meta-analysis of the nine randomized trials showed a significant benefit in terms of OS (hazard ratio: 0.75 [95% CI: 0.66–0.85]; p < 0.01). Only programmed death ligand-1 positive-high cancers derive a significant OS benefit. In this meta-analysis, there is moderate evidence that the addition of immune checkpoint inhibitors to chemotherapy may improve both OS compared with chemotherapy alone.


2019 ◽  
Vol 26 (4) ◽  
pp. 995-999 ◽  
Author(s):  
Steffi Thomas ◽  
Chay Bae ◽  
Tabanor Joy-Ann ◽  
William Traverse

Introduction The landscape for the treatment of metastatic melanoma has been revolutionized with the introduction immune checkpoint inhibitors. Immune checkpoint inhibitors have now become the standard of care for the treatment of cancers. These immune agents including programmed death receptor-1 inhibitors, programmed death-ligand 1 inhibitors and cytotoxic T-lymphocyte antigen-4 inhibitors have shown promising results but have been associated with numerous immune-related complications. Pembrolizumab, a programmed death receptor-1 inhibitor, has been associated with a number of immune-related adverse events affecting multiple organ systems including integument, ocular, endocrine, cardiovascular, pulmonary, renal, gastrointestinal, and musculoskeletal system. Case report We present a case of an 88-year-old Caucasian male with metastatic melanoma of the face with metastasis to the right fifth cranial nerve and into the right cavernous sinus. He underwent resection of the melanoma and was placed on pembrolizumab at 2 mg/kg every three weeks. Interestingly, 24 months on pembrolizumab therapy, he developed corneal erosions, oral and genital ulcerations. Management and outcome Patient completed his 24 months of pembrolizumab and was started on prednisone and colchicine with improvement in his symptoms. At his follow-up eight months, he had recurrence of an oral ulcer. Discussion Here we present a rare case of an elderly male on pembrolizumab who suffered from corneal erosions, oral and genital ulcers, a syndrome similar to Behcet’s disease. Given that pembrolizumab and other immune checkpoint inhibitors are being utilized in the treatment of cancers, physicians should be aware of the wide range immune-related adverse events including the possible Behcet’s-like syndrome presentation.


Cancers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 738 ◽  
Author(s):  
Raju K. Vaddepally ◽  
Prakash Kharel ◽  
Ramesh Pandey ◽  
Rohan Garje ◽  
Abhinav B. Chandra

Cancer is associated with higher morbidity and mortality and is the second leading cause of death in the US. Further, in some nations, cancer has overtaken heart disease as the leading cause of mortality. Identification of molecular mechanisms by which cancerous cells evade T cell-mediated cytotoxic damage has led to the modern era of immunotherapy in cancer treatment. Agents that release these immune brakes have shown activity to recover dysfunctional T cells and regress various cancer. Both cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and Programmed Death-1 (PD-1) play their role as physiologic brakes on unrestrained cytotoxic T effector function. CTLA-4 (CD 152) is a B7/CD28 family; it mediates immunosuppression by indirectly diminishing signaling through the co-stimulatory receptor CD28. Ipilimumab is the first and only FDA-approved CTLA-4 inhibitor; PD-1 is an inhibitory transmembrane protein expressed on T cells, B cells, Natural Killer cells (NKs), and Myeloid-Derived Suppressor Cells (MDSCs). Programmed Death-Ligand 1 (PD-L1) is expressed on the surface of multiple tissue types, including many tumor cells and hematopoietic cells. PD-L2 is more restricted to hematopoietic cells. Blockade of the PD-1 /PDL-1 pathway can enhance anti-tumor T cell reactivity and promotes immune control over the cancerous cells. Since the FDA approval of ipilimumab (human IgG1 k anti-CTLA-4 monoclonal antibody) in 2011, six more immune checkpoint inhibitors (ICIs) have been approved for cancer therapy. PD-1 inhibitors nivolumab, pembrolizumab, cemiplimab and PD-L1 inhibitors atezolizumab, avelumab, and durvalumab are in the current list of the approved agents in addition to ipilimumab. In this review paper, we discuss the role of each immune checkpoint inhibitor (ICI), the landmark trials which led to their FDA approval, and the strength of the evidence per National Comprehensive Cancer Network (NCCN), which is broadly utilized by medical oncologists and hematologists in their daily practice.


2018 ◽  
Vol 23 (11) ◽  
pp. 1388-1390 ◽  
Author(s):  
Jeremy M. O'Connor ◽  
Kathi Seidl‐Rathkopf ◽  
Aracelis Z. Torres ◽  
Paul You ◽  
Kenneth R. Carson ◽  
...  

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