LZTR1 is a melanoma oncogene that promotes invasion and suppresses apoptosis.

Leucine zipper like transcription regulator 1 (LZTR1) is amplified in acral melanomas, is required for melanocytes and melanoma cell proliferation, and it induces anchorage-independent growth, by yet unknown mechanisms. We therefore performed comprehensive studies to identify its activity in melanomas employing proximity biotinylation and co-immunoprecipitation combined with LC-MS/MS proteomics and molecular characterization. The results show that LZTR1 regulates the ubiquitin proteasome system in melanoma cells and also associates with actin-related proteins and actin cytoskeleton organization.

The ERVK3-1 Microprotein Interacts with the HUSH Complex.

Human endogenous retroviruses (hERVs) are noninfectious molecular remnants of ancient exogenous retroviruses that now make up 8% of the human genome. The ubiquitously expressed human locus was recently annotated as encoding a 109-amino acid endogenous retroviral Rec microprotein. However, because this locus was thought to be noncoding until recently, it is currently unknown whether the ERVK3-1 microprotein has a function in human cells.

Blocking Nitrosylation Induces Immunogenic Cell Death by Sensitizing NRAS-Mutant Melanoma to MEK Inhibitors.

Unlabelled: Activating NRAS mutations occur in 15% to 25% of all melanomas. However, this subtype remains refractory to existing therapeutics, including immunotherapy and RAS inhibitors; therefore, identifying innovative treatment strategies is of utmost importance. We investigated the role of nitrosylation, a nitric oxide-induced posttranslational modification, in melanoma progression and therapeutic resistance.

FAK inhibition combined with the RAF-MEK clamp avutometinib overcomes resistance to targeted and immune therapies in BRAF V600E melanoma.

Widespread BRAF mutations result in persistent RAS-RAF-MEK-ERK (MAPK) signaling in melanoma. BRAF (BRAFi) and MEK (MEKi) inhibitors are approved for BRAF V600E melanomas, including those progressing on immunotherapy; however, rapid resistance to these agents highlights the need for novel strategies. Here, transcriptome analysis of BRAF V600E melanomas from patients resistant to BRAFi and MEKi shows activation of focal adhesion signaling.

Circulating tumor-reactive KIRCD8 T cells suppress anti-tumor immunity in patients with melanoma.

Effective anti-tumor immunity is driven by cytotoxic CD8 T cells with specificity for tumor antigens. However, the factors that control successful tumor rejection are not well understood. Here we identify a subpopulation of CD8 T cells that are tumor-antigen-specific and can be identified by KIR expression but paradoxically impair anti-tumor immunity in patients with melanoma.

Prognostic and therapeutic insights into MIF, DDT, and CD74 in melanoma.

Macrophage Migration Inhibitory Factor (MIF) and its homolog D-dopachrome Tautomerase (DDT) have been implicated as drivers of tumor progression across a variety of cancers. Recent evidence suggests MIF as a therapeutic target in immune checkpoint inhibition (ICI) resistant melanomas, however clinical evidence of MIF and particularly of DDT remain limited. This retrospective study analyzed 97 patients treated at Yale for melanoma between 2002-2020.

Digital spatial proteomic profiling reveals immune checkpoints as biomarkers in lymphoid aggregates and tumor microenvironment of desmoplastic melanoma.

Background: Desmoplastic melanoma (DM) is a rare melanoma subtype characterized by dense fibrous stroma, a propensity for local recurrence, and a high response rate to programmed cell death protein 1 (PD-1) blockade. Occult sentinel lymph node positivity is significantly lower in both pure and mixed DM than in conventional melanoma, underscoring the need for better prognostic biomarkers to inform therapeutic strategies.

Methods: We assembled a tissue microarray comprising various cores of tumor, stroma, and lymphoid aggregates from 45 patients with histologically confirmed DM diagnosed between 1989 and 2018.

Circulating Tumor Reactive KIR+CD8+ T cells Suppress Anti-Tumor Immunity in Patients with Melanoma.

Effective anti-tumor immunity is largely driven by cytotoxic CD8 T cells that can specifically recognize tumor antigens. However, the factors which ultimately dictate successful tumor rejection remain poorly understood. Here we identify a subpopulation of CD8 T cells which are tumor antigen-specific in patients with melanoma but resemble KIRCD8 T cells with a regulatory function (Tregs).

Unannotated microprotein EMBOW regulates the interactome and chromatin and mitotic functions of WDR5.

The conserved WD40-repeat protein WDR5 interacts with multiple proteins both inside and outside the nucleus. However, it is currently unclear whether and how the distribution of WDR5 between complexes is regulated. Here, we show that an unannotated microprotein EMBOW (endogenous microprotein binder of WDR5) dually encoded in the human SCRIB gene interacts with WDR5 and regulates its binding to multiple interaction partners, including KMT2A and KIF2A.

CD4 T cells and toxicity from immune checkpoint blockade.

Immune-related toxicities, otherwise known as immune-related adverse events (irAEs), occur in a substantial fraction of cancer patients treated with immune checkpoint inhibitors (ICIs). Ranging from asymptomatic to life-threatening, ICI-induced irAEs can result in hospital admission, high-dose corticosteroid treatment, ICI discontinuation, and in some cases, death. A deeper understanding of the factors underpinning severe irAE development will be essential for improved irAE prediction and prevention, toward maximizing the benefits and safety profiles of ICIs.

Dynamic changes of circulating soluble PD-1/PD-L1 and its association with patient survival in immune checkpoint blockade-treated melanoma.

Immune checkpoint PD-1 and its ligand PD-L1 lead to T cell exhaustion, and a high level of circulating soluble PD-L1 at baseline indicates a poor prognosis in melanoma and other solid tumor types. Here we show that the dynamic changes of circulating soluble PD-1 and PD-L1 across the course of immune checkpoint blockades (ICBs) and their changes associate with patient survival in melanoma in a retrospective study. A high change of soluble PD-L1 level at a time-point but not PD-1 significantly increased the mortality, whereas a high change of soluble PD-1/PD-L1 ratio significantly reduced the mortality.

Integrative molecular and clinical profiling of acral melanoma links focal amplification of 22q11.21 to metastasis.

Acral melanoma, the most common melanoma subtype among non-White individuals, is associated with poor prognosis. However, its key molecular drivers remain obscure. Here, we perform integrative genomic and clinical profiling of acral melanomas from 104 patients treated in North America (n = 37) or China (n = 67).

T cell characteristics associated with toxicity to immune checkpoint blockade in patients with melanoma.

Severe immune-related adverse events (irAEs) occur in up to 60% of patients with melanoma treated with immune checkpoint inhibitors (ICIs). However, it is unknown whether a common baseline immunological state precedes irAE development. Here we applied mass cytometry by time of flight, single-cell RNA sequencing, single-cell V(D)J sequencing, bulk RNA sequencing and bulk T cell receptor (TCR) sequencing to study peripheral blood samples from patients with melanoma treated with anti-PD-1 monotherapy or anti-PD-1 and anti-CTLA-4 combination ICIs.

A novel anti-melanoma SRC-family kinase inhibitor.

The major drawback of melanoma therapy with BRAF and MAPK inhibitors is the innate and acquired drug resistance. We therefore explored alternative targets and developed a new compound, SAB298, that is a SRC-family kinase (SFK) inhibitor. The drug is cytotoxic to patient-derived melanoma cells regardless of oncogene expression and inhibits tumor growth .

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.

A Serum Protein Signature Associated with Outcome after Anti-PD-1 Therapy in Metastatic Melanoma.

A mass spectrometry analysis was performed using serum from patients receiving checkpoint inhibitors to define baseline protein signatures associated with outcome in metastatic melanoma. Pretreatment serum was obtained from a development set of 119 melanoma patients on a trial of nivolumab with or without a multipeptide vaccine and from patients receiving pembrolizumab, nivolumab, ipilimumab, or both nivolumab and ipilimumab. Spectra were obtained using matrix-assisted laser desorption/ionization time of flight mass spectrometry.

Future perspectives in melanoma research "Melanoma Bridge", Napoli, November 30th-3rd December 2016.

Major advances have been made in the treatment of cancer with targeted therapy and immunotherapy; several FDA-approved agents with associated improvement of 1-year survival rates became available for stage IV melanoma patients. Before 2010, the 1-year survival were quite low, at 30%; in 2011, the rise to nearly 50% in the setting of treatment with Ipilimumab, and rise to 70% with BRAF inhibitor monotherapy in 2013 was observed. Even more impressive are 1-year survival rates considering combination strategies with both targeted therapy and immunotherapy, now exceeding 80%.

Spitz nevi and Spitzoid melanomas: exome sequencing and comparison with conventional melanocytic nevi and melanomas.

We performed exome sequencing of 77 melanocytic specimens composed of Spitz nevi (n=29), Spitzoid melanomas (n=27), and benign melanocytic nevi (n=21), and compared the results with published melanoma sequencing data. Our study highlights the prominent similarity between Spitzoid and conventional melanomas with similar copy number changes and high and equal numbers of ultraviolet-induced coding mutations affecting similar driver genes. Mutations in MEN1, PRKAR1A, and DNMT3A in Spitzoid melanomas may indicate involvement of the protein kinase A pathway, or a role of DNA methylation in the disease.

Interlesional diversity of T cell receptors in melanoma with immune checkpoints enriched in tissue-resident memory T cells.

Heterogeneity of tumor cells and their microenvironment can affect outcome in cancer. Blockade of immune checkpoints (ICPs) expressed only on a subset of immune cells leads to durable responses in advanced melanoma. Tissue-resident memory T (T) cells have recently emerged as a distinct subset of memory T cells in nonlymphoid tissues.