Systemic GM-CSF Recruits Effector T Cells into the Tumor Microenvironment in Localized Prostate Cancer

BackgroundRegulatory T (Treg) cells are vital for preventing autoimmunity but are a major barrier to robust cancer immunity as the tumor microenvironment (TME) recruits and promotes their function. The deregulated cellular metabolism of tumor cells leads to a metabolite-depleted, hypoxic, and acidic TME. While the TME impairs the effector function of highly glycolytic tumor infiltrating CD8 T cells, Treg cell suppressive function is maintained. Further, studies of in vitro induced and ex vivo Treg cells reveal a distinct metabolic profile compared to effector T cells. Thus, it may be that the altered metabolic landscape of the TME and the increased activity of intratumoral Treg cells are linked.MethodsFlow cytometry, isotopic flux analysis, Foxp3 driven Cre-lox, glucose tracers, Seahorse extracellular flux analysis, RNA sequencing.ResultsHere we show Treg cells display heterogeneity in terms of their glucose metabolism and can engage an alternative metabolic pathway to maintain their high suppressive function and proliferation within the TME and other tissues. Tissue derived Treg cells (both at the steady state and under inflammatory conditions) show broad heterogeneity in their ability to take up glucose. However, glucose uptake correlates with poorer suppressive function and long-term functional stability, and culture of Treg cells in high glucose conditions decreased suppressive function. Treg cells under low glucose conditions upregulate genes associated with the uptake and metabolism of the glycolytic end-product lactic acid. Treg cells withstand high lactate conditions, and lactate treatment prevents the destabilizing effects of high glucose culture. Treg cells utilize lactate within the TCA cycle and generate phosphoenolpyruvate (PEP), a critical intermediate that can fuel intratumoral Treg cell proliferation in vivo. Using mice with a Treg cell-restricted deletion of lactate transporter Slc16a1 (MCT1) we show MCT1 is dispensable for peripheral Treg cell function but required intratumorally, resulting in slowed tumor growth and prolonged survival.ConclusionsThese data support a model in which Treg cells are metabolically flexible such that they can utilize ‘alternative’ metabolites present in the TME to maintain their suppressive identity. Further, our studies support the notion that tumors avoid immune destruction not only by depriving effector T cells of essential nutrients, but also by metabolically supporting regulatory T cells.

Download Full-text

KY1044 to target the ICOS pathways inducing intratumoral Treg depletion and agonism of effector T cells: Preliminary pharmacodynamic markers from a phase 1/2 multicenter trial.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.15_suppl.2626 ◽

2021 ◽

Vol 39 (15_suppl) ◽

pp. 2626-2626

Author(s):

Chia-Chi Lin ◽

Aung Naing ◽

Manish R. Patel ◽

Howard A. Burris III ◽

Giuseppe Curigliano ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Phase 1 ◽

Single Agent ◽

Effector T Cells ◽

Post Treatment ◽

Target Engagement ◽

Treg Depletion ◽

Gm Csf ◽

Tumor Biopsies

2626 Background: Inducible T-cell co-stimulator (ICOS) is an important co-stimulatory receptor on effector T cells (Teffs) that also promotes tumor growth due to its high expression on regulatory T cells (Tregs). KY1044 is a fully human IgG1 that targets ICOS, acting via a dual mode of action (MoA) by depleting ICOShigh Tregs and stimulating ICOSLow Teffs. A Phase 1/2 clinical trial (NCT03829501) is currently assessing the safety and preliminary efficacy of KY1044, as a single agent and in combination with atezolizumab, in subjects with advanced relapsed/refractory malignancies. Using longitudinal blood samples and tumor biopsies, we aim to correlate KY1044 target engagement levels with pharmacodynamic (PD) properties (e.g. dual MoA) in the tumor microenvironment (TME) and the circulation. Methods: Phase 1 subjects were enrolled in dose escalation and enrichment cohorts to evaluate the effect of KY1044 as monotherapy (0.8 – 240 mg) Q3W and in combination (0.8 – 80 mg) with atezolizumab (1200 mg) Q3W. PBMCs, plasma and tumor biopsies were collected over the first 3 cycles to confirm target engagement and KY1044 MoA. The sample analysis included: immunohistochemistry (IHC) of tumor samples (ICOS, FOXP3 and CD8); circulating T cell immunoprofiling and receptor occupancy by chip-cytometry; PBMC and tumor sample pre- and post-treatment transcriptomic analysis; and the assessment of circulating cytokines (e.g. GM-CSF). Results: As assessed in PBMCs, full/prolonged ICOS target engagement on T cells was confirmed in subjects receiving a flat dose of 8 to 240 mg, while partial/transient saturation was observed at lower doses (0.8-2.4 mg). The target engagement was not affected by atezolizumab. The immune cell profiling showed changes in some populations, but there was no significant depletion of peripheral ICOS+ cells. In contrast, pre- and post-treatment IHC analysis of ICOS+/FOXP3+ cells in tumor biopsies confirmed a KY1044-dose dependent reduction of ICOS+ Tregs and maintenance of CD8+ T cells in the TME. Together, this resulted in an increased intratumoral CD8+/ICOS+ Treg ratio at all doses, plateauing from subjects receiving a flat KY1044 dose of 8 mg. KY1044-dependent agonism was indirectly assessed by measuring circulating cytokine levels. A post-dosing transient induction of GM-CSF was evident in subjects dosed with KY1044 at the 0.8 and 2.4 mg dose, whereas minimal induction was observed at dose of 8 mg and higher. Conclusions: LongitudinalPDdata confirmed the expected KY1044 MoA, namely ICOS Treg depletion and increased CD8/ICOS Treg ratio in the TME as well as T cell co-stimulation. The observed PD responses are currently being further explored in a more homogenous patient population.

Download Full-text

Phenotype, distribution, generation, and functional and clinical relevance of Th17 cells in the human tumor environments

Blood ◽

10.1182/blood-2009-03-208249 ◽

2009 ◽

Vol 114 (6) ◽

pp. 1141-1149 ◽

Cited By ~ 468

Author(s):

Ilona Kryczek ◽

Mousumi Banerjee ◽

Pui Cheng ◽

Linhua Vatan ◽

Wojciech Szeliga ◽

...

Keyword(s):

T Cells ◽

Tumor Microenvironment ◽

Regulatory T Cells ◽

Cancer Patients ◽

Th17 Cells ◽

Human Tumor ◽

Active Role ◽

Effector T Cells ◽

Cell Phenotype ◽

Effector Cells

Abstract Th17 cells play an active role in autoimmune diseases. However, the nature of Th17 cells is poorly understood in cancer patients. We studied Th17 cells, the associated mechanisms, and clinical significance in 201 ovarian cancer patients. Tumor-infiltrating Th17 cells exhibit a polyfunctional effector T-cell phenotype, are positively associated with effector cells, and are negatively associated with tumor-infiltrating regulatory T cells. Tumor-associated macrophages promote Th17 cells through interleukin-1β (IL-1β), whereas tumor-infiltrating regulatory T cells inhibit Th17 cells through an adenosinergic pathway. Furthermore, through synergistic action between IL-17 and interferon-γ, Th17 cells stimulate CXCL9 and CXCL10 production to recruit effector T cells to the tumor microenvironment. The levels of CXCL9 and CXCL10 are associated with tumor-infiltrating effector T cells. The levels of tumor-infiltrating Th17 cells and the levels of ascites IL-17 are reduced in more advanced diseases and positively predict patient outcome. Altogether, Th17 cells may contribute to protective human tumor immunity through inducing Th1-type chemokines and recruiting effector cells to the tumor microenvironment. Inhibition of Th17 cells represents a novel immune evasion mechanism. This study thus provides scientific and clinical rationale for developing novel immune-boosting strategies based on promoting the Th17 cell population in cancer patients.

Download Full-text

Activated Lymphocyte Recruitment Into the Tumor Microenvironment Following Preoperative Sipuleucel-T for Localized Prostate Cancer

JNCI Journal of the National Cancer Institute ◽

10.1093/jnci/dju268 ◽

2014 ◽

Vol 106 (11) ◽

Cited By ~ 98

Author(s):

Lawrence Fong ◽

Peter Carroll ◽

Vivian Weinberg ◽

Stephen Chan ◽

Jera Lewis ◽

...

Keyword(s):

Prostate Cancer ◽

Tumor Microenvironment ◽

Localized Prostate Cancer

Download Full-text

Tumor Microenvironment: No Effector T Cells without Dendritic Cells

Cancer Cell ◽

10.1016/j.ccell.2017.04.007 ◽

2017 ◽

Vol 31 (5) ◽

pp. 614-615 ◽

Cited By ~ 19

Author(s):

Christina Pfirschke ◽

Marie Siwicki ◽

Hsin-Wei Liao ◽

Mikael J. Pittet

Keyword(s):

T Cells ◽

Dendritic Cells ◽

Tumor Microenvironment ◽

Effector T Cells

Download Full-text

Caloric restriction impairs regulatory T-cells within the tumor microenvironment after radiation and primes effector T-cells

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/j.ijrobp.2021.02.029 ◽

2021 ◽

Author(s):

Gregor Manukian ◽

Charles Kivolowitz ◽

Tiziana DeAngelis ◽

Anuradha Shastri ◽

Jason E. Savage ◽

...

Keyword(s):

T Cells ◽

Tumor Microenvironment ◽

Regulatory T Cells ◽

Caloric Restriction ◽

Effector T Cells

Download Full-text

Tumor Cells and the Extracellular Matrix Dictate the Pro-Tumoral Profile of Macrophages in CRC

Cancers ◽

10.3390/cancers13205199 ◽

2021 ◽

Vol 13 (20) ◽

pp. 5199

Author(s):

Sara Coletta ◽

Silvia Lonardi ◽

Francesca Sensi ◽

Edoardo D’Angelo ◽

Matteo Fassan ◽

...

Keyword(s):

T Cells ◽

Tumor Microenvironment ◽

Tumor Cells ◽

Metastatic Potential ◽

Effector T Cells ◽

Macrophage Phenotype ◽

Mhc Ii ◽

Cytokines And Chemokines ◽

Antigen Presenting ◽

Cell Effector

Tumor-associated macrophages (TAMs) are major components of the tumor microenvironment. In colorectal cancer (CRC), a strong infiltration of TAMs is accompanied by a decrease in effector T cells and an increase in the metastatic potential of CRC. We investigated the functional profile of TAMs infiltrating CRC tissue by immunohistochemistry, flow cytometry, ELISA, and qRT-PCR and their involvement in impairing the activation of effector T cells. In CRC biopsies, we evidenced a high percentage of macrophages with low expression of the antigen-presenting complex MHC-II and high expression of CD206. Monocytes co-cultured with tumor cells or a decellularized tumor matrix differentiated toward a pro-tumoral macrophage phenotype characterized by decreased expression of MHC-II and CD86 and increased expression of CD206 and an abundant release of pro-tumoral cytokines and chemokines. We demonstrated that the hampered expression of MHC-II in macrophages is due to the downregulation of the MHC-II transactivator CIITA and that this effect relies on increased expression of miRNAs targeting CIITA. As a result, macrophages become unable to present antigens to CD4 T lymphocytes. Our data suggest that the tumor microenvironment contributes to defining a pro-tumoral profile of macrophages infiltrating CRC tissue with impaired capacity to activate T cell effector functions.

Download Full-text

Neoadjuvant sipuleucel-T in localized prostate cancer: Effects on immune cells within the prostate tumor microenvironment.

Journal of Clinical Oncology ◽

10.1200/jco.2012.30.15_suppl.2564 ◽

2012 ◽

Vol 30 (15_suppl) ◽

pp. 2564-2564 ◽

Cited By ~ 1

Author(s):

Lawrence Fong ◽

Vivian K. Weinberg ◽

Stephen E Chan ◽

John M Corman ◽

Christopher L Amling ◽

...

Keyword(s):

Prostate Cancer ◽

Immune Response ◽

T Cells ◽

Cd4 T Cells ◽

Prostate Tumor ◽

Localized Prostate Cancer ◽

Cellular Immunotherapy ◽

Cancer Tissue ◽

Estimated Blood Loss ◽

Pre Treatment

2564 Background: Sipuleucel-T is an FDA-approved autologous cellular immunotherapy for patients with asymptomatic or minimally symptomatic metastatic castrate resistant prostate cancer (mCRPC). To date, studies of sipuleucel-T in patients with mCRPC have studied immune response in peripheral blood. The effects of sipuleucel-T on prostate tumors are unknown. Methods: NeoACT (P07-1; NCT00715104) is an open-label, phase 2 study of patients with localized prostate cancer who received sipuleucel-T prior to radical prostatectomy (RP) to examine the immunologic effects of treatment on prostate tissue. Patients received 3 infusions of sipuleucel-T at approximately 2-week intervals, beginning 6-7 weeks prior to RP. The primary endpoint was the change in the frequency of lymphocytes between prostate biopsies (pre-treatment) and RP tissue (post-treatment), as assessed by immunohistochemistry (IHC). Results: The median age of the 42 enrolled patients was 61 years, and all had an ECOG performance status of 0. Thirty-eight patients received all 3 pre-RP sipuleucel-T infusions. To date, tissue IHC analysis has been completed on 32 patients. Treatment-related AEs were manageable and transient. Sipuleucel-T did not appear to impact surgery, as judged by operative complications, procedure time, and estimated blood loss. Frequent events that occurred ≤1 day after infusion (>10% of patients) were fatigue, headache, and myalgia. Significant increases (≥3 fold) in CD3+ and CD4+ T cell populations were observed at the tumor interface (where benign and malignant glands interface), compared with the pre-treatment biopsy, benign RP tissue, and tumor RP tissue (ANOVA post hoc Newman-Keuls test: p<0.0001 for each comparison). FoxP3+ CD4+ T cells were also increased (p=0.0005) at the tumor interface, but represented a small fraction of the observed CD4+ T cells. Conclusions: Neoadjuvant sipuleucel-T treatment is associated with an increased frequency of T cells in prostate cancer tissue at the interface of the benign and malignant glands. These data suggest that sipuleucel-T can modulate the presence of lymphocytes at the prostate tumor site. Work is ongoing to more fully characterize the immune response.

Download Full-text