Risk-associated alterations in marrow T cells in pediatric leukemia.

Current management of childhood leukemia is tailored based on disease risk determined by clinical features at presentation. Whether properties of the host immune response impact disease risk and outcome is not known. Here, we combine mass cytometry, single cell genomics, and functional studies to characterize the BM immune environment in children with B cell acute lymphoblastic leukemia and acute myelogenous leukemia at presentation. T cells in leukemia marrow demonstrate evidence of chronic immune activation and exhaustion/dysfunction, with attrition of naive T cells and TCF1+ stem-like memory T cells and accumulation of terminally differentiated effector T cells. Marrow-infiltrating NK cells also exhibit evidence of dysfunction, particularly in myeloid leukemia. Properties of immune cells identified distinct immune phenotype-based clusters correlating with disease risk in acute lymphoblastic leukemia. High-risk immune signatures were associated with expression of stem-like genes on tumor cells. These data provide a comprehensive assessment of the immune landscape of childhood leukemias and identify targets potentially amenable to therapeutic intervention. These studies also suggest that properties of the host response with depletion of naive T cells and accumulation of terminal-effector T cells may contribute to the biologic basis of disease risk. Properties of immune microenvironment identified here may also impact optimal application of immune therapies, including T cell-redirection approaches in childhood leukemia.

Differential effects of PD-L1 versus PD-1 blockade on myeloid inflammation in human cancer.

BACKGROUNDPD-1 and PD-L1 have been studied interchangeably in the clinic as checkpoints to reinvigorate T cells in diverse tumor types. Data for biologic effects of checkpoint blockade in human premalignancy are limited.METHODSWe analyzed the immunologic effects of PD-L1 blockade in a clinical trial of atezolizumab in patients with asymptomatic multiple myeloma (AMM), a precursor to clinical malignancy. Genomic signatures of PD-L1 blockade in purified monocytes and T cells in vivo were also compared with those following PD-1 blockade in lung cancer patients. Effects of PD-L1 blockade on monocyte-derived DCs were analyzed to better understand its effects on myeloid antigen-presenting cells.RESULTSIn contrast to anti-PD-1 therapy, anti-PD-L1 therapy led to a distinct inflammatory signature in CD14+ monocytes and increase in myeloid-derived cytokines (e.g., IL-18) in vivo. Treatment of AMM patients with atezolizumab led to rapid activation and expansion of circulating myeloid cells, which persisted in the BM. Blockade of PD-L1 on purified monocyte-derived DCs led to rapid inflammasome activation and synergized with CD40L-driven DC maturation, leading to greater antigen-specific T cell expansion.CONCLUSIONThese data show that PD-L1 blockade leads to distinct systemic immunologic effects compared with PD-1 blockade in vivo in humans, particularly manifest as rapid myeloid activation. These findings also suggest an additional role for PD-L1 as a checkpoint for regulating inflammatory phenotype of myeloid cells and antigen presentation in DCs, which may be harnessed to improve PD-L1-based combination therapies.TRIAL REGISTRATIONNCT02784483.FUNDINGThis work is supported, in part, by funds from NIH/NCI (NCI CA197603, CA238471, and CA208328).

Early alterations in stem-like/resident T cells, innate and myeloid cells in the bone marrow in preneoplastic gammopathy.

Preneoplastic lesions carry many of the antigenic targets found in cancer cells but often exhibit prolonged dormancy. Understanding how the host response to premalignancy is maintained and altered during malignant transformation is needed to prevent cancer. In order to understand the immune microenvironment in precursor monoclonal gammopathy of undetermined significance (MGUS) and myeloma, we analyzed bone marrow immune cells from 12 healthy donors and 26 MGUS/myeloma patients by mass cytometry and concurrently profiled transcriptomes of 42,606 single immune cells from these bone marrows. Compared to age-matched healthy donors, memory T cells from both MGUS and myeloma patients exhibit greater terminal-effector differentiation. However, memory T cells in MGUS show greater enrichment of stem-like TCF1/7hi cells. Clusters of T cells with stem-like and tissue-residence genes were also found to be enriched in MGUS by single-cell transcriptome analysis. Early changes in both NK and myeloid cells were also observed in MGUS. Enrichment of stem-like T cells correlated with a distinct genomic profile of myeloid cells and levels of Dickkopf-1 in bone-marrow plasma. These data describe the landscape of changes in both innate and adaptive immunity in premalignancy and suggest that attrition of the bone-marrow-resident T cell compartment due to loss of stem-like cells may underlie loss of immune surveillance in myeloma.

Low levels of intra-tumoural T cells in breast cancer identify clinically frail patients with shorter disease-specific survival.

OBJECTIVES: The global health status of older patients with cancer influences their clinical course, but little is known regarding the influence of the immune system on the global health of older patients with cancer. The goal of this study was to assess the relationships between patient fitness/frailty status and survival, and the local tumour immune environment of older patients with breast cancer. MATERIALS AND METHODS: In a cohort of 58 older patients with breast cancer (over 70 years of age), fluorescence microscopy was used to investigate whether levels of intra-tumoural T cells (CD3+) and granulocytic cells (CD15+) could predict clinical outcome, and/or whether they correlated with patient physical and mental performance as evaluated by comprehensive geriatric assessment. RESULTS: We observed that patients with higher levels of intra-tumoural T cells were fitter according to a number of clinical health measures including G8 (p = 0.006), Karnofsky Index (p = 0.0372), and Leuven Oncology Frailty Score (LOFS) (p = 0.0187). In contrast, high relative levels of granulocytic cells were found in patients with poorer clinical health (LOFS, p = 0.0474). Furthermore, high levels of T cells but not granulocytic cells were associated with longer breast cancer-specific survival (p = 0.0444). CONCLUSIONS: This is the first study to show that low relative levels of intra-tumoural T cells are associated with inferior patient fitness. In contrast to T cells, we observed that intra-tumoural granulocytic cells displayed an inverse relationship with patient performance. Further research is needed to determine whether boosting the level of intra-tumoural T cells in older non-fit patients can result in improved outcome.

Early B cell changes predict autoimmunity following combination immune checkpoint blockade.

Combination checkpoint blockade (CCB) targeting inhibitory CTLA4 and PD1 receptors holds promise for cancer therapy. Immune-related adverse events (IRAEs) remain a major obstacle for the optimal application of CCB in cancer. Here, we analyzed B cell changes in patients with melanoma following treatment with either anti-CTLA4 or anti-PD1, or in combination. CCB therapy led to changes in circulating B cells that were detectable after the first cycle of therapy and characterized by a decline in circulating B cells and an increase in CD21lo B cells and plasmablasts. PD1 expression was higher in the CD21lo B cells, and B cell receptor sequencing of these cells demonstrated greater clonality and a higher frequency of clones compared with CD21hi cells. CCB induced proliferation in the CD21lo compartment, and single-cell RNA sequencing identified B cell activation in cells with genomic profiles of CD21lo B cells in vivo. Increased clonality of circulating B cells following CCB occurred in some patients. Treatment-induced changes in B cells preceded and correlated with both the frequency and timing of IRAEs. Patients with early B cell changes experienced higher rates of grade 3 or higher IRAEs 6 months after CCB. Thus, early changes in B cells following CCB may identify patients who are at increased risk of IRAEs, and preemptive strategies targeting B cells may reduce toxicities in these patients.

CD14+ HLA-DR-/low MDSCs are elevated in the periphery of early-stage breast cancer patients and suppress autologous T cell proliferation.

PURPOSE: Despite the recent expansion in the use of immunotherapy for many cancer types, it is still not a standard treatment for breast cancer. Identifying differences in the immune systems of breast cancer patients compared to healthy women might provide insight into potential targets for immunotherapy and thus may assist its clinical implementation. METHODS: Multi-colour flow cytometry was used to investigate myeloid and lymphoid populations in the peripheral blood of breast cancer patients (n = 40) and in the blood of healthy age-matched women (n = 25). We additionally performed functional testing to identify immune suppressive mechanisms used by circulating CD14+ myeloid cells from breast cancer patients. RESULTS: Our results show that breast cancer patients have significantly elevated frequencies of cells with the monocytic myeloid-derived suppressor cell (mMDSC) phenotype CD14+ HLA-DR-/low compared with healthy women (p < 0.01). We also observed higher levels of earlier differentiated T cells and correspondingly lower levels of T cells in later stages of differentiation (p < 0.05). These disease-associated differences could already be detected in early-stage breast cancer patients in stages 1 and 2 (n = 33 of 40) (p < 0.05). Levels of circulating T cells correlated with certain clinical features and with patient age (p < 0.05). Functional tests showed that CD14+ myeloid cells from breast cancer patients more potently suppressed autologous T cell proliferation than CD14+ cells from healthy women (p < 0.01). Subsequent investigation determined that suppression was mediated in part by reactive oxygen species, because inhibiting this pathway partially restored T cell proliferation (p < 0.01). CONCLUSION: Our results highlight the potential importance of cells with mMDSC phenotypes in breast cancer, identifiable already at early stages of disease. This may provide a basis for identifying possible new therapeutic targets to enhance anti-cancer immunity.

Immune profiles of elderly breast cancer patients are altered by chemotherapy and relate to clinical frailty.

BACKGROUND: Effective therapeutic management of elderly patients with cancer, on an individual basis, remains a clinical challenge. Here, we identify novel biomarkers to assess elderly patients (≥70 years of age) with breast cancer undergoing treatment with or without chemotherapy. METHODS: We performed comprehensive geriatric assessment and measured markers sensitive to alteration in ageing, including leukocyte telomere length, CMV serostatus, levels of circulating growth factors and cytokines, and immune profiling of T cell and myeloid populations in blood before and at 3 months and 12 months after initiation of therapy, using flow cytometry. RESULTS: We observed changes in immune profiles over time that were specific to patients receiving chemotherapy; these patients had elevated CD4+ T effector memory re-expressing CD45RA (TEMRA) cells and relatively lower CD8+ central memory cells at 3 months, with normalized levels after 12 months. Patients' baseline immune profiles correlated with markers such as telomere length, cytomegalovirus (CMV) serostatus and levels of circulating cytokines. We also identified correlations between baseline immune profile and geriatric assessment, i.e. more frail patients had higher levels of granulocytic cells but lower levels of cells with suppressor phenotypes including myeloid-derived suppressor cells and regulatory T cells, although none of the examined immune populations correlated with chronological age. Importantly, immune profiles prior to therapy predicted unexpected hospitalizations in patients receiving chemotherapy. CONCLUSION: These findings suggest that immune profiling may represent a novel complementary approach to more accurately assess the global health status of the elderly patient with breast cancer and select the most appropriate individual treatment option. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00849758 . Registered on 20 February 2009.

The impact of adjuvant chemotherapy in older breast cancer patients on clinical and biological aging parameters.

PURPOSE: This prospective observational study aimed to evaluate the impact of adjuvant chemotherapy on biological and clinical markers of aging and frailty. METHODS: Women ≥ 70 years old with early breast cancer were enrolled after surgery and assigned to a chemotherapy (Docetaxel and Cyclophosphamide) group (CTG, n=57) or control group (CG, n=52) depending on their planned adjuvant treatment. Full geriatric assessment (GA) and Quality of Life (QoL) were evaluated at inclusion (T0), after 3 months (T1) and at 1 year (T2). Blood samples were collected to measure leukocyte telomere length (LTL), levels of interleukin-6 (IL-6) and other circulating markers potentially informative for aging and frailty: Interleukin-10 (IL-10), Tumor Necrosis Factor Alpha (TNF-α), Insulin-like Growth Factor 1 (IGF-1), Monocyte Chemotactic Protein 1 (MCP-1) and Regulated on Activation, Normal T cell Expressed and Secreted (RANTES). RESULTS: LTL decreased significantly but comparably in both groups, whereas IL-6 was unchanged at T2. However, IL-10, TNF-α, IGF-1 and MCP-1 suggested a minor biological aging effect of chemotherapy. Clinical frailty and QoL decreased at T1 in the CTG, but recovered at T2, while remaining stable in the CG. CONCLUSIONS: Chemotherapy (TC) is unlikely to amplify clinical aging or induce frailty at 1 year. Accordingly, there is no impact on the most established aging biomarkers (LTL, IL-6).

Prognostic impact of circulating Her-2-reactive T-cells producing pro- and/or anti-inflammatory cytokines in elderly breast cancer patients.

BACKGROUND: Treating elderly breast cancer patients remains a challenge but the increasing availability of immunotherapeutic approaches instills optimism that these tumours may also be susceptible to immune control. Because aging leads to a number of alterations in the immune system ("immunosenescence") reflecting potential exhaustion which could compromise immunomodulatory antibody therapy, here we have assessed the immunocompetence of elderly breast cancer patients compared with a group of younger patients, and related this to the 5-year survival of the former. METHODS: T-cell responses to Her-2 peptide pools in vitro were assessed by analyzing pro- and anti-inflammatory cytokine production by CD4+ and CD8+ T-cells in 40 elderly and 35 younger breast cancer patients. RESULTS: The proportions of older and younger patients whose peripheral T-cells responded to Her-2 peptides in vitro were found to be similar, although a significantly higher fraction of younger patients possessed IL-2-producing CD4+ Her-2-reactive T-cells than in the elderly (p = 0.03). However, IL-2 production did not impart a survival benefit to the latter. In contrast, there was a survival benefit of possessing Her-2-reactive CD8+ T-cells, but this was abrogated in patients if they also had CD4+ Her-2-responsive T-cells that producedIL-5 and/or IL-17 (p = 0.01). This resulted in a 5-yr survival rate of only 29 % compared to 76 % for patients whose her-2-reactive CD4+ T-cells did not produceIL-5 and/or IL-17. Additionally, patients whose CD8+ T-cells produced TNF had a significantly better survival than those that did not (93 % compared to 52 %, p = 0.01), whereas no survival benefit was attributable to possessing IFN-γ-producing cells. CONCLUSIONS: Elderly breast cancer patients appear perfectly immunocompetent to respond to Her-2 peptide pools in vitro, with response patterns very similar to younger patients. The nature of this response is associated with 5-year survival of these elderly patients, suggesting that boosting anti-tumor responses and modulating the nature of the T-cell response is likely to be effective even in potentially immunosenescent elderly breast cancer patients, and might be useful for predicting which patients are most likely to benefit from such treatments.

The prognostic impact of specific CD4 T-cell responses is critically dependent on the target antigen in melanoma.

The melanoma-associated antigens Melan-A and NY-ESO-1 stimulate different T-cell responses in late-stage melanoma patients. Either CD4+ or CD8+ T-cell reactivity against NY-ESO-1 was associated with better prognosis, but for Melan-A, only CD8+ but not CD4+ T-cell responses were associated with longer survival.

Presence of circulating Her2-reactive CD8 + T-cells is associated with lower frequencies of myeloid-derived suppressor cells and regulatory T cells, and better survival in older breast cancer patients.

INTRODUCTION: Breast cancer is one of the most common cancers among women. Its incidence is increasing in many countries and a higher number of older women are now being diagnosed with the disease. Immune parameters are implicated in disease progression, and the frequencies of both myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs), associated with tumour burden, have been suggested to be indicators of poor prognosis in cases of metastatic breast cancer. METHODS: Here, we have assessed the frequency of peripheral Tregs and MDSCs in relation to in vitro T cell responses to Her2 antigen in 40 untreated breast cancer patients 65 to 87 years of age at diagnosis. RESULTS: The five-year survival rate of patients who mounted a CD8+ T cell response to Her2 peptides and had a lower frequency of Lin⁻CD14⁺HLA-DR⁻MDSCs was 100% compared to only 38% in patients without Her2-reactive CD8⁺ T cells and with higher frequencies of MDSCs (P = 0.03). Patients who lacked a CD8 response to Her2 tended to have higher frequencies of MDSCs. Similarly, patients who lacked a CD8 response to Her2 and had higher frequencies of CD4⁺Foxp3⁺CD127lowCD25⁺ Tregs had only 50% survival compared to the 100% survival of patients who did mount a CD8 response and had lower frequencies of Tregs (P = 0.03). A similar trend was observed for activated (CD4⁺CD45RA⁻Foxp3hi) but not resting Tregs (CD4⁺CD45RA⁺FoxP3⁺). This survival advantage was observed in both metastatic and non-metastatic patients. CONCLUSIONS: Our data demonstrate a negative role of both MDSCs and Tregs in the prognosis of breast cancer patients, the mechanism of which might be through dampening favourable CD8+ T cell immune responses to tumour-associated antigens.

Circulating CD4+ T cells that produce IL4 or IL17 when stimulated by melan-A but not by NY-ESO-1 have negative impacts on survival of patients with stage IV melanoma.

PURPOSE: We initially observed that the presence of circulating NY-ESO-1- and/or Melan-A-specific T cells in patients with stage IV melanoma was significantly associated with prolonged survival. Here, we report the ways in which the phenotypes and functions of these T cells differentially affect survival in patients preselected for NY-ESO-1 and/or Melan-A reactivity. EXPERIMENTAL DESIGN: We assayed functional antigen-reactive T cells recognizing NY-ESO-1 and/or Melan-A after in vitro stimulation using overlapping peptide pools. After restimulation, we assayed six cytokines simultaneously by intracellular cytokine staining. This allowed us to analyze the functional antigen response of both CD4(+) and CD8(+) T cells at the single-cell level. RESULTS: We observed that NY-ESO-1 stimulated mainly CD4(+) T cells, whereas Melan-A more often stimulated CD8(+) T cells. NY-ESO-1 reactivity was not associated with an additional impact on survival, whether CD4(+) T cells, CD8(+) T cells, or both types of T cells were responding. In contrast, recognition of Melan-A by CD4(+) T cells was associated with reduced survival in our cohort of patients preselected for NY-ESO-1 and/or Melan-A reactivity (that is, in patients with exceptionally long survival). We further observed a negative effect on survival in patients with CD4(+) T cells producing IL4 and IL17 upon Melan-A stimulation. Their prognosis was comparable to patients without any Melan-A reactivity. CONCLUSIONS: The nature and prognostic impact of specific T-cell responses is different according to targeted antigen. Independent from phenotype and functional aspects, NY-ESO-1 reactivity is associated with good prognosis. In terms of Melan-A, antigen-specific CD8(+) but not CD4(+) responses are associated with prolonged survival. Clin Cancer Res; 20(16); 4390-9. ©2014 AACR.