Causes of death and patterns of metastatic disease at the end of life for patients with advanced melanoma in the immunotherapy era.

Despite remarkable advances in immunotherapy, melanoma remains a significant cause of cancer mortality. Many factors concerning melanoma mortality are poorly understood, posing an obstacle to optimal care. We conducted a retrospective observational cohort study of 183 patients with metastatic melanoma who died following immunotherapy treatment to investigate sites of metastases at death, settings of death, and mechanisms of death.

Immunotherapy utilization in stage IIIA melanoma: less may be more.

Background: Immunotherapy agents are approved for adjuvant treatment of stage III melanoma; however, evidence for survival benefit in early stage III disease is lacking. Current guidelines for adjuvant immunotherapy utilization in stage IIIA rely on clinician judgment, creating an opportunity for significant variation in prescribing patterns. This study aimed to characterize current immunotherapy practice variations and to compare patient outcomes for different prescribing practices in stage IIIA melanoma.

Causal identification of single-cell experimental perturbation effects with CINEMA-OT.

Recent advancements in single-cell technologies allow characterization of experimental perturbations at single-cell resolution. While methods have been developed to analyze such experiments, the application of a strict causal framework has not yet been explored for the inference of treatment effects at the single-cell level. Here we present a causal-inference-based approach to single-cell perturbation analysis, termed CINEMA-OT (causal independent effect module attribution + optimal transport).

Subsets of IFN Signaling Predict Response to Immune Checkpoint Blockade in Patients with Melanoma.

Purpose: IFN signaling in the tumor microenvironment is a critical determinant of both response and resistance of cancer to immune checkpoint inhibitors (ICI). We hypothesized that distinct patterns of IFN signaling in melanoma are associated with clinical response or resistance to ICIs.

Experimental Design: Two tissue microarrays containing samples from 97 patients with metastatic melanoma who received nivolumab, pembrolizumab, or a combination of ipilimumab and nivolumab at Yale New Haven Hospital between 2011 and 2017 were randomized into discovery and validation cohorts.

PI3K activation allows immune evasion by promoting an inhibitory myeloid tumor microenvironment.

Background: Oncogenes act in a cell-intrinsic way to promote tumorigenesis. Whether oncogenes also have a cell-extrinsic effect on suppressing the immune response to cancer is less well understood.

Methods: We use an expression screen of known cancer-associated somatic mutations in mouse syngeneic tumor models treated with checkpoint blockade to identify oncogenes that promote immune evasion.

Going viral: HBV-specific CD8 tissue-resident memory T cells propagate anti-tumor immunity.

The nature of the epitopes recognized by tumor-infiltrating T cells is not clearly defined. In this issue of Immunity, Cheng et al. demonstrate that tissue-resident memory CD8 T cells specific for hepatitis B virus-derived antigens exhibit potent anti-tumor properties and correlate with relapse-free survival in patients with resected hepatocellular carcinoma.

Reprogramming of the esophageal squamous carcinoma epigenome by SOX2 promotes ADAR1 dependence.

Esophageal squamous cell carcinomas (ESCCs) harbor recurrent chromosome 3q amplifications that target the transcription factor SOX2. Beyond its role as an oncogene in ESCC, SOX2 acts in development of the squamous esophagus and maintenance of adult esophageal precursor cells. To compare Sox2 activity in normal and malignant tissue, we developed engineered murine esophageal organoids spanning normal esophagus to Sox2-induced squamous cell carcinoma and mapped Sox2 binding and the epigenetic and transcriptional landscape with evolution from normal to cancer.

Epigenetic silencing by SETDB1 suppresses tumour intrinsic immunogenicity.

Epigenetic dysregulation is a defining feature of tumorigenesis that is implicated in immune escape. Here, to identify factors that modulate the immune sensitivity of cancer cells, we performed in vivo CRISPR-Cas9 screens targeting 936 chromatin regulators in mouse tumour models treated with immune checkpoint blockade. We identified the H3K9 methyltransferase SETDB1 and other members of the HUSH and KAP1 complexes as mediators of immune escape.

Spatial signatures identify immune escape via PD-1 as a defining feature of T-cell/histiocyte-rich large B-cell lymphoma.

T-cell/histiocyte-rich large B-cell lymphoma (TCRLBCL) is an aggressive variant of diffuse large B-cell lymphoma (DLBCL) characterized by rare malignant B cells within a robust but ineffective immune cell infiltrate. The mechanistic basis of immune escape in TCRLBCL is poorly defined and not targeted therapeutically. We performed a genetic and quantitative spatial analysis of the PD-1/PD-L1 pathway in a multi-institutional cohort of TCRLBCLs and found that malignant B cells harbored PD-L1/PD-L2 copy gain or amplification in 64% of cases, which was associated with increased PD-L1 expression (P = .

Vitamin D intake is associated with decreased risk of immune checkpoint inhibitor-induced colitis.

Background: There is a lack of predictive markers informing on the risk of colitis in patients treated with immune checkpoint inhibitors (ICIs). The aim of this study was to identify potential factors associated with development of ICI colitis.

Methods: We performed a retrospective analysis of melanoma patients at Dana-Farber Cancer Institute who received PD-1, CTLA-4, or combination ICIs between May 2011 to October 2017.

Author Correction: Subsets of exhausted CD8 T cells differentially mediate tumor control and respond to checkpoint blockade.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Phase II Study of Avelumab in Patients With Mismatch Repair Deficient and Mismatch Repair Proficient Recurrent/Persistent Endometrial Cancer.

Purpose: Despite the tissue-agnostic approval of pembrolizumab in mismatch repair deficient (MMRD) solid tumors, important unanswered questions remain about the role of immune checkpoint blockade in mismatch repair-proficient (MMRP) and -deficient endometrial cancer (EC).

Methods: This phase II study evaluated the PD-L1 inhibitor avelumab in two cohorts of patients with EC: (1) MMRD/ (polymerase ε) cohort, as defined by immunohistochemical (IHC) loss of expression of one or more mismatch repair (MMR) proteins and/or documented mutation in the exonuclease domain of ; and (2) MMRP cohort with normal IHC expression of all MMR proteins. Coprimary end points were objective response (OR) and progression-free survival at 6 months (PFS6).

Subsets of exhausted CD8 T cells differentially mediate tumor control and respond to checkpoint blockade.

T cell dysfunction is a hallmark of many cancers, but the basis for T cell dysfunction and the mechanisms by which antibody blockade of the inhibitory receptor PD-1 (anti-PD-1) reinvigorates T cells are not fully understood. Here we show that such therapy acts on a specific subpopulation of exhausted CD8 tumor-infiltrating lymphocytes (TILs). Dysfunctional CD8 TILs possess canonical epigenetic and transcriptional features of exhaustion that mirror those seen in chronic viral infection.

Loss of ADAR1 in tumours overcomes resistance to immune checkpoint blockade.

Most patients with cancer either do not respond to immune checkpoint blockade or develop resistance to it, often because of acquired mutations that impair antigen presentation. Here we show that loss of function of the RNA-editing enzyme ADAR1 in tumour cells profoundly sensitizes tumours to immunotherapy and overcomes resistance to checkpoint blockade. In the absence of ADAR1, A-to-I editing of interferon-inducible RNA species is reduced, leading to double-stranded RNA ligand sensing by PKR and MDA5; this results in growth inhibition and tumour inflammation, respectively.

Quantitating T cell cross-reactivity for unrelated peptide antigens.

Quantitating the frequency of T cell cross-reactivity to unrelated peptides is essential to understanding T cell responses in infectious and autoimmune diseases. Here we used 15 mouse or human CD8+ T cell clones (11 antiviral, 4 anti-self) in conjunction with a large library of defined synthetic peptides to examine nearly 30,000 TCR-peptide MHC class I interactions for cross-reactions. We identified a single cross-reaction consisting of an anti-self TCR recognizing a poxvirus peptide at relatively low sensitivity.

The structural dynamics and energetics of an immunodominant T cell receptor are programmed by its Vbeta domain.

Immunodominant and public T cell receptor (TCR) usage is relatively common in many viral diseases yet surprising in the context of the large naive TCR repertoire. We examined the highly conserved Vbeta17:Valpha10.2 JM22 T cell response to the influenza matrix peptide (58-66)-HLA-A*0201 (HLA-A2-flu) through extensive kinetic, thermodynamic, and structural analyses.