Gut Microbiota and Immune Checkpoint Inhibitors-Based Immunotherapy

: Application of immune checkpoint inhibitors (ICIs) is a major breakthrough in the field of cancer therapy, which has displayed tremendous potential in various types of malignancies. However, their response rates range widely in different cancer types and a significant number of patients experience immune-related adverse effects (irAEs) induced by these drugs, limiting the proportion of patients who can truly benefit from ICIs. Gut microbiota has gained increasing attention due to its emerging role in regulating the immune system. In recent years, numerous studies have shown that gut microbiota can modulate antitumor response, as well as decrease the risk of colitis due to ICIs in patients receiving immunotherapy. The present review analyzed recent progress of relevant basic and clinical studies in this area and explored new perspectives to enhance the efficacy of ICIs and alleviate associated irAEs via manipulation of the gut microbiota.

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Are Long-Chain Polyunsaturated Fatty Acids the Link between the Immune System and the Microbiome towards Modulating Cancer?

Medicines ◽

10.3390/medicines5030102 ◽

2018 ◽

Vol 5 (3) ◽

pp. 102 ◽

Cited By ~ 9

Author(s):

Leodevico Ilag

Keyword(s):

Fatty Acids ◽

Immune System ◽

Gut Microbiota ◽

Polyunsaturated Fatty Acids ◽

Immune Checkpoint ◽

Immune Checkpoint Inhibitors ◽

Checkpoint Inhibitors ◽

Optimal Level ◽

Common Denominator ◽

Long Chain

Three recent studies revealed synergy between immune-checkpoint inhibitors and the microbiome as a new approach in the treatment of cancer. Incidentally, there has been significant progress in understanding the role of polyunsaturated fatty acids (PUFAs) in modulating cancer and the immune system, as well as in regulating the microbiome. Inflammation seems to be the common denominator among these seemingly unrelated biological entities—immune system, the microbiome, and long-chain polyunsaturated fatty acids (LC-PUFAs). This commentary presents a hypothesis proposing the existence of an optimal level of LC-PUFAs that nurtures the suitable gut microbiota preventing dysbiosis. This synergy between optimal LC-PUFAs and gut microbiota helps the immune system overcome the immunosuppressive tumour microenvironment including enhancing the efficacy of immune checkpoint inhibitors. A model on how LC-PUFAs (such as omega(n)-3 and n-6 fatty acids) forms a synergistic triad with the immune system and the microbiome in regulating inflammation to maintain homeostasis is presented. The principles underlying the hypothesis provide a basis in managing and even preventing cancer and other chronic diseases associated with inflammation.

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Immune Checkpoint Inhibitors for the Treatment of Cancer: Clinical Impact and Mechanisms of Response and Resistance

Annual Review of Pathology Mechanisms of Disease ◽

10.1146/annurev-pathol-042020-042741 ◽

2020 ◽

Vol 16 (1) ◽

Author(s):

Sreya Bagchi ◽

Robert Yuan ◽

Edgar G. Engleman

Keyword(s):

Immune Checkpoint ◽

Immune Checkpoint Inhibitors ◽

Immune Cell ◽

Cytotoxic T Lymphocyte ◽

Checkpoint Inhibitors ◽

Annual Review ◽

Publication Date ◽

Number Of Patients ◽

Cancer Types ◽

Cell Changes

Immune checkpoint inhibitors (ICIs) have made an indelible mark in the field of cancer immunotherapy. Starting with the approval of anti-cytotoxic T lymphocyte-associated protein 4 (anti-CTLA-4) for advanced-stage melanoma in 2011, ICIs—which now also include antibodies against programmed cell death 1 (PD-1) and its ligand (PD-L1)—quickly gained US Food and Drug Administration approval for the treatment of a wide array of cancer types, demonstrating unprecedented extension of patient survival. However, despite the success of ICIs, resistance to these agents restricts the number of patients able to achieve durable responses, and immune-related adverse events complicate treatment. Thus, a better understanding of the requirements for an effective and safe antitumor immune response following ICI therapy is needed. Studies of both tumoral and systemic changes in the immune system following ICI therapy have yielded insight into the basis for both efficacy and resistance. Ultimately, by building on these insights, researchers should be able to combine ICIs with other agents, or design new immunotherapies, to achieve broader and more durable efficacy as well as greater safety. Here, we review the history and clinical utility of ICIs, the mechanisms of resistance to therapy, and local and systemic immune cell changes associated with outcome. Expected final online publication date for the Annual Review of Pathology: Mechanisms of Disease, Volume 16 is January 25, 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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The Role of Gut Microbiota in Overcoming Resistance to Checkpoint Inhibitors in Cancer Patients: Mechanisms and Challenges

International Journal of Molecular Sciences ◽

10.3390/ijms22158036 ◽

2021 ◽

Vol 22 (15) ◽

pp. 8036

Author(s):

Youssef Bouferraa ◽

Andrea Chedid ◽

Ghid Amhaz ◽

Ahmed El Lakkiss ◽

Deborah Mukherji ◽

...

Keyword(s):

Immune System ◽

Gut Microbiota ◽

Immune Checkpoint ◽

Immune Checkpoint Inhibitors ◽

Checkpoint Inhibitors ◽

Response To Treatment ◽

Multiple Cancer ◽

Ongoing Research ◽

Cancer Pathogenesis

The introduction of immune checkpoint inhibitors has constituted a major revolution in the treatment of patients with cancer. In contrast with the traditional cytotoxic therapies that directly kill tumor cells, this treatment modality enhances the ability of the host’s immune system to recognize and target cancerous cells. While immune checkpoint inhibitors have been effective across multiple cancer types, overcoming resistance remains a key area of ongoing research. The gut microbiota and its role in cancer immunosurveillance have recently become a major field of study. Gut microbiota has been shown to have direct and systemic effects on cancer pathogenesis and hosts anti-tumor immune response. Many studies have also shown that the host microbiota profile plays an essential role in the response to immunotherapy, especially immune checkpoint inhibitors. As such, modulating this microbial environment has offered a potential path to overcome the resistance to immune checkpoint inhibitors. In this review, we will talk about the role of microbiota in cancer pathogenesis and immune-system activity. We will also discuss preclinical and clinical studies that have increased our understanding about the roles and the mechanisms through which microbiota influences the response to treatment with immune checkpoint inhibitors.

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Immune Checkpoint Inhibitors in Human Glioma Microenvironment

Frontiers in Immunology ◽

10.3389/fimmu.2021.679425 ◽

2021 ◽

Vol 12 ◽

Author(s):

Amina Ghouzlani ◽

Sarah Kandoussi ◽

Mariam Tall ◽

Konala Priyanka Reddy ◽

Soumaya Rafii ◽

...

Keyword(s):

Immune Response ◽

Immune System ◽

Immune Checkpoint ◽

Immune Checkpoint Inhibitors ◽

Checkpoint Inhibitors ◽

Immune Checkpoint Blockade ◽

General Concept ◽

The Central Nervous System ◽

Cancer Types ◽

Glioma Microenvironment

Gliomas are the most common primary brain tumors in adults. Despite the fact that they are relatively rare, they cause significant morbidity and mortality. High-grade gliomas or glioblastomas are rapidly progressing tumors with a very poor prognosis. The presence of an intrinsic immune system in the central nervous system is now more accepted. During the last decade, there has been no major progress in glioma therapy. The lack of effective treatment for gliomas can be explained by the strategies that cancer cells use to escape the immune system. This being said, immunotherapy, which involves blockade of immune checkpoint inhibitors, has improved patients’ survival in different cancer types. This novel cancer therapy appears to be one of the most promising approaches. In the present study, we will start with a review of the general concept of immune response within the brain and glioma microenvironment. Then, we will try to decipher the role of various immune checkpoint inhibitors within the glioma microenvironment. Finally, we will discuss some promising therapeutic pathways, including immune checkpoint blockade and the body’s effective anti-glioma immune response.

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Immune Checkpoint Inhibitors: Basics and Challenges

Current Medicinal Chemistry ◽

10.2174/0929867324666170804143706 ◽

2019 ◽

Vol 26 (17) ◽

pp. 3009-3025 ◽

Cited By ~ 8

Author(s):

Bin Li ◽

Ho Lam Chan ◽

Pingping Chen

Keyword(s):

Immune Checkpoint ◽

Immune Checkpoint Inhibitors ◽

Checkpoint Inhibitors ◽

Complete Response ◽

Modern World ◽

Basic Principles ◽

Mutation Status ◽

Anti Cancer ◽

Cancer Types ◽

Shed Light

Cancer is one of the most deadly diseases in the modern world. The last decade has witnessed dramatic advances in cancer treatment through immunotherapy. One extremely promising means to achieve anti-cancer immunity is to block the immune checkpoint pathways – mechanisms adopted by cancer cells to disguise themselves as regular components of the human body. Many review articles have described a variety of agents that are currently under extensive clinical evaluation. However, while checkpoint blockade is universally effective against a broad spectrum of cancer types and is mostly unrestricted by the mutation status of certain genes, only a minority of patients achieve a complete response. In this review, we summarize the basic principles of immune checkpoint inhibitors in both antibody and smallmolecule forms and also discuss potential mechanisms of resistance, which may shed light on further investigation to achieve higher clinical efficacy for these inhibitors.

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Rethinking immune checkpoint blockade: ‘Beyond the T cell’

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2020-001460 ◽

2021 ◽

Vol 9 (1) ◽

pp. e001460 ◽

Cited By ~ 1

Author(s):

Xiuting Liu ◽

Graham D Hogg ◽

David G DeNardo

Keyword(s):

Immune System ◽

T Cell ◽

Immune Checkpoint ◽

Immune Checkpoint Inhibitors ◽

Antitumor Immunity ◽

Checkpoint Inhibitors ◽

Clinical Success ◽

Immune Checkpoint Blockade ◽

Checkpoint Blockade

The clinical success of immune checkpoint inhibitors has highlighted the central role of the immune system in cancer control. Immune checkpoint inhibitors can reinvigorate anti-cancer immunity and are now the standard of care in a number of malignancies. However, research on immune checkpoint blockade has largely been framed with the central dogma that checkpoint therapies intrinsically target the T cell, triggering the tumoricidal potential of the adaptive immune system. Although T cells undoubtedly remain a critical piece of the story, mounting evidence, reviewed herein, indicates that much of the efficacy of checkpoint therapies may be attributable to the innate immune system. Emerging research suggests that T cell-directed checkpoint antibodies such as anti-programmed cell death protein-1 (PD-1) or programmed death-ligand-1 (PD-L1) can impact innate immunity by both direct and indirect pathways, which may ultimately shape clinical efficacy. However, the mechanisms and impacts of these activities have yet to be fully elucidated, and checkpoint therapies have potentially beneficial and detrimental effects on innate antitumor immunity. Further research into the role of innate subsets during checkpoint blockade may be critical for developing combination therapies to help overcome checkpoint resistance. The potential of checkpoint therapies to amplify innate antitumor immunity represents a promising new field that can be translated into innovative immunotherapies for patients fighting refractory malignancies.

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363 Vactosertib and durvalumab as second or later line treatment for PD-L1 positive non-small cell lung cancer: interim result

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2020-sitc2020.0363 ◽

2020 ◽

Vol 8 (Suppl 3) ◽

pp. A388-A388

Author(s):

Byoung Chul Cho ◽

Ki Hyeong Lee ◽

Ji-Youn Han ◽

Byoung Yong Shim ◽

Hye Ryun Kim ◽

...

Keyword(s):

Immune Checkpoint ◽

Objective Response Rate ◽

Immune Checkpoint Inhibitors ◽

Advanced Nsclc ◽

Response Rate ◽

Checkpoint Inhibitors ◽

Objective Response ◽

Platinum Based Chemotherapy ◽

Number Of Patients ◽

Anti Tumor Activity

BackgroundTargeting transforming growth factor-β (TGF-β) is reported to augment the efficacy of immune checkpoint inhibitors (ICIs) through either enhanced anti-tumor immunity or the correction of tumor microenvironment (TME). Therefore, the combination of vactosertib, a highly selective TGF-β RI kinase inhibitor, and durvalumab is anticipated to improve anti-tumor activity of the ICI. A phase 1b/2a study was conducted to evaluate the combination of vactosertib and durvalumab in patients with advanced NSCLC who progressed after platinum-based chemotherapy.MethodsPatients were treated with vactosertib at a dose of 200 mg twice daily (five days on and two days off) and durvalumab at a dose of 1500 mg every four weeks. Eligible patients were ≥19 years old with good performance status (ECOG 0–1) and have no prior exposure to immune checkpoint inhibitors or other TGF- β R1 kinase inhibitors. The objectives of this analysis were to evaluate the safety, antitumor activity including objective response rate (ORR), duration of response (DOR), and time to response (TTR) as well as circulating pharmacodynamic biomarkers related to TGF-β signaling. Response was assessed per RECIST (v1.1).ResultsBy August 4 2020, twenty-six PD-L1 positive (SP263 assay) patients were analyzed. Median age was 61.5 years (range 48–83), 69.2% were male, median number of previous lines of chemotherapy was 1 (range 1–4), and all patients were PD-L1 positive (15 patients with PD-L1≥25% and 11 patients with PD-L1 1–24%). The most frequently reported treatment-related adverse events (TRAE) were itching (38.5%) and skin rash (34.6%), but no Gr≥3 itching and rash were observed. Each case of the following was reported as Grade 3 TRAEs: adrenal insufficiency, anemia, and pneumonitis; Grade 4 TRAE, CPK increase, was observed in one patient. Objective response rate was 30.8% and 40.0% in patients with PD-L1≥1% and ≥25% respectively. Circulating PAI-1 and CTGF evaluated in 15 patients decreased significantly on Cycle 1 day 5. Ongoing biomarker results will be presented.ConclusionsThe combination of vactosertib and durvalumab has demonstrated a manageable safety profile and encouraging anti-tumor activity as a potential therapeutic strategy in patients with advanced NSCLC. The efficacy outcomes of this combination in a larger number of patients with advanced NSCLC will be followed.Trial RegistrationNCT03732274Ethics ApprovalThe study was approved by Ethics Board of Severance Hospital (4-2018-0892), National Cancer Center (NCC2019-0057), St. Vincent’s Hospital (VC19MDDF0205), and Chungbuk National University Hospital (2019-08-015).

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Determinants of resistance to VEGF-TKI and immune checkpoint inhibitors in metastatic renal cell carcinoma

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-021-01961-3 ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Revati Sharma ◽

Elif Kadife ◽

Mark Myers ◽

George Kannourakis ◽

Prashanth Prithviraj ◽

...

Keyword(s):

Renal Cell Carcinoma ◽

Cell Carcinoma ◽

Immune Checkpoint ◽

Renal Cell ◽

Immune Checkpoint Inhibitors ◽

Kinase Inhibitors ◽

Checkpoint Inhibitors ◽

Resistance Mechanisms ◽

Number Of Patients ◽

Angiogenesis Pathway

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.

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Immune-Related Adverse Events (irAE) in Cancer Immune Checkpoint Inhibitors (ICI) and Survival Outcomes Correlation: To Rechallenge or Not?

Cancers ◽

10.3390/cancers13050989 ◽

2021 ◽

Vol 13 (5) ◽

pp. 989

Author(s):

Heidar J. Albandar ◽

Jacob Fuqua ◽

Jasim M. Albandar ◽

Salahuddin Safi ◽

Samuel A. Merrill ◽

...

Keyword(s):

Adverse Events ◽

Immune Checkpoint ◽

Immune Checkpoint Inhibitors ◽

Checkpoint Inhibitors ◽

Survival Outcomes ◽

Limited Data ◽

Risk Of Death ◽

Survival Difference ◽

Histopathologic Diagnosis ◽

Cancer Types

Introduction: There is growing recognition of immune related adverse events (irAEs) from immune checkpoint therapies being correlated with treatment outcomes in certain malignancies. There are currently limited data or consensus to guide management of irAEs with regards to treatment rechallenge. Methods: We conducted a retrospective analysis with an IRB-approved protocol of adult patients seen at the WVU Cancer Institute between 2011–2019 with a histopathologic diagnosis of active cancers and were treated with immune checkpoint inhibitors (ICI) therapy. Results: Demographics were similar between the ICI interrupted irAE groups within cancer types. Overall, out of 548 patients who received ICI reviewed, there were 133 cases of ≥1 irAE found of any grade. Being treated with anti-CTLA-4 inhibitor ICI was associated with lower risk of death compared to anti-PD-1 ICI. The overall survival difference observed for irAE positive patients, between rechallenged (37.8 months, reinitiated with/without interruption; 38.6 months, reinitiated after interruption) and interrupted/non-reinitiated (i.e., discontinued) groups (24.9 months) was not statistically significant, with a numerical trend favoring the former. Conclusions: Our exploratory study did not identify significantly different survival outcomes among the Appalachian West Virginia adult cancer patients treated with ICI who developed irAE and had treatment reinitiated after interruption, when compared with those not reinitiated.

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Genetic ancestry and clinical outcomes to immune checkpoint inhibitors among seven common cancers.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.15_suppl.10536 ◽

2021 ◽

Vol 39 (15_suppl) ◽

pp. 10536-10536

Author(s):

Amin Nassar ◽

Elio Adib ◽

Sarah Abou Alaiwi ◽

Elie Akl ◽

Talal El Zarif ◽

...

Keyword(s):

Cell Carcinoma ◽

Clinical Outcomes ◽

Immune Checkpoint ◽

Immune Checkpoint Inhibitors ◽

Checkpoint Inhibitors ◽

East Asian ◽

Genetic Ancestry ◽

Sequencing Data ◽

Histologic Subtype ◽

Cancer Types

10536 Background: Prior studies and clinical trials report associations between self-reported race and clinical outcomes to Immune Checkpoint Inhibitors (ICIs). However, comprehensive studies of ancestry-associated differences in clinical outcomes have not been performed. We derived genetic ancestry scores and assessed clinical outcomes in 1341 patients with cancer treated with ICIs. Methods: Patients at the Dana-Farber Cancer Institute treated with ICIs only and with relevant cancer types and targeted exome sequencing data (Oncopanel) were included. Relevant cancer types included colorectal adenocarcinoma (CRC), esophagogastric adenocarcinoma (EGC), head and neck squamous cell carcinoma (HNSCC), melanoma, non-small cell lung cancer (NSCLC), renal cell carcinoma (RCC), and urothelial carcinoma (UC). We developed a bioinformatics pipeline to infer fine-scale genetic ancestry for each patient (n=1341) directly from tumor sequencing data by leveraging off and on-target sequenced reads and external ancestry reference panels. Three ancestry scores were determined (African, East Asian, European). Overall survival (OS) and time-to-treatment failure (TTF) were compared by Cox logistic regression between ancestral populations. Hazard ratio (HR) was derived using multivariable analysis, adjusted for single versus combination therapy, prior lines of therapy, and tumor mutational burden (TMB, as percentiles). Results: Median follow-up was 37.8 months (m; interquartile range: 35.7-39.5m). Common cancer types included CRC (n=52), EGC (n=114), HNSCC (n=88), melanoma (n=274), NSCLC (n=571), RCC (n=99), and UC (n=143). A higher East Asian ancestry (EAS) was significantly associated with worse OS ( p=0.03) and TTF ( p=0.002) in patients with RCC, independent of the histologic subtype (Table). There was no significant association between any of the three ancestral populations and clinical outcomes in the other 6 cancer types. Conclusions: We described clinical outcomes to ICIs across three global populations in 7 cancers. As the medical field re-evaluates the use of self-reported race in clinical decision-making, we utilize a novel ancestry pipeline that can be readily applied to tumor-only sequencing panels and better characterize non-white populations. We find no ancestry differences in clinical outcomes except in patients with RCC treated with ICIs which will require future validation. We plan to analyze genomic correlates of response by ancestry in each of the cancer types to better understand these diverge clinical behaviors.[Table: see text]

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