Karina Silina

An Immune Atlas of Clear Cell Renal Cell Carcinoma

Summary Immune cells in the tumor microenvironment modulate cancer progression and are attractive therapeutic targets. Macrophages and T cells are key components of the microenvironment, yet their phenotypes and relationships in this ecosystem and to clinical outcomes are ill defined. We used mass cytometry with extensive antibody panels to perform in-depth immune profiling of samples from 73 clear cell renal cell carcinoma (ccRCC) patients and five healthy controls. In 3.5 million measured cells, we identified 17 tumor-associated macrophage phenotypes, 22 T cell phenotypes, and a distinct immune composition correlated with progression-free survival, thereby presenting an in-depth human atlas of the immune tumor microenvironment in this disease. This study revealed potential biomarkers and targets for immunotherapy development and validated tools that can be used for immune profiling of other tumor types.

Maturation of tertiary lymphoid structures and recurrence of stage II and III colorectal cancer

ABSTRACT Tertiary lymphoid structures (TLS) are associated with favorable outcome in non-metastatic colorectal carcinoma (nmCRC), but the dynamics of TLS maturation and its association with effective anti-tumor immune surveillance in nmCRC are unclear. Here, we hypothesized that not only the number of TLS but also their composition harbors information on recurrence risk in nmCRC. In a comprehensive molecular, tissue, laboratory, and clinical analysis of 109 patients with stage II/III nmCRC, we assessed TLS numbers and degree of maturation in surgical specimens by multi-parameter immunofluorescence of follicular dendritic cell (FDC) and germinal center (GC) markers. TLS formed in most tumors and were significantly more prevalent in highly-microsatellite-instable (MSI-H) and/or BRAF-mutant nmCRC. We could distinguish three sequential TLS maturation stages which were characterized by increasing prevalence of FDCs and mature B-cells: [1] Early TLS, composed of dense lymphocytic aggregates without FDCs, [2] Primary follicle-like TLS, having FDCs but no GC reaction, and [3] Secondary follicle-like TLS, having an active GC reaction. A simple integrated TLS immunoscore reflecting these parameters identified a large subgroup of nmCRC patients with a very low risk of recurrence independently of clinical co-variables such as ECOG performance status, age, stage, and adjuvant chemotherapy. We conclude that (1) mismatch repair and BRAF mutation status are associated with the formation of TLS in nmCRC, (2) TLS formation in nmCRC follows sequential maturation steps, culminating in germinal center formation, and (3) this maturation process harbors important prognostic information on the risk of disease recurrence.

Rational Combination of Immunotherapies with Clinical Efficacy in Mice with Advanced Cancer

An efficacious combination of immunomodulatory treatments was identified in a late-stage prostate cancer model that prevented tolerance, promoted a sustained tumor-specific CD8+ T cells response, and cured tumors when given with adoptively transferred tumor-specific T cells. In the context of cancer, naïve T cells are insufficiently primed and become progressively dysfunctional. Boosting antitumor responses by blocking PD-1 or CTLA-4 results in durable clinical responses only in a limited proportion of cancer patients, suggesting that other pathways must be targeted to improve clinical efficacy. Our preclinical study in TRAMP mice comparing 14 different immune interventions identified anti-CD40 + IL2/anti-IL2 complexes + IL12Fc as a uniquely efficacious treatment that prevents tolerance induction, promotes priming of sustained, protective tumor-specific CD8+ T cells, and cures late-stage cancer when given together with adoptively transferred tumor-specific T cells. We propose that improving signals 2 (costimulation) and 3 (cytokines) together with fresh tumor-specific, rather than boosting of dysfunctional preexisting memory, T cells represents a potent therapy for advanced cancer. Cancer Immunol Res; 3(11); 1279–88. ©2015 AACR.

Abstract B85: Tertiary lymphoid structures in chemotherapy-treated and untreated lung squamous cell carcinoma patients

Tertiary lymphoid structures (TLS) form in chronically inflamed tissues and contain organized compartments of T cells, B cells and follicular dendritic cells (FDCs). TLS were first noticed in autoimmune diseases where they support ectopic germinal center (GC) reactions and facilitate the activation and infiltration of immune cells. In cancer B cell and mature DC markers have been used for TLS detection because of their frequent localisation in TLS, and show a significant association with improved survival in several tumor types. Together these studies have driven the interest in TLS as a potential site of anti-tumor immune response activation and/or facilitation of lymphocyte infiltration. Here we aimed to characterise TLS as a microanatomical structure excluding non-organised lymphocytic infiltrates and to determine their prognostic value and association with clinico-pathologic parameters in non-small cell lung cancer patients. We characterised TLS density and presence of GCs in tumor center and periphery using HE December 1-4, 2014; Orlando, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2015;3(10 Suppl):Abstract nr B85.