Project description:Murine MYC-HCC were treated with control IgG or anti PDL1 or anti CTLA4, or their combination. Tumors were sequenced using Nanostring IO360.
Project description:To identify proteomic signatures associated with hepatocellular carcinoma driven by MYC overexpression, proteomics was performed on the LAP-tTA/tetO-MYC mouse conditional liver cancer model. Upon MYC activation, mice form liver cancer. Differential proteomics was performed in "MYC on" (MYC-HCC) mouse liver tumors versus mouse control normal liver tissue (where MYC was not overexpressed to drive tumorigenesis -- "MYC off").
Project description:Comparative transcriptional profiling of MYC driven HCC and MYC/Twist1 driven HCC during tumor progression, regression and recurrence.
Project description:The MYC oncogene is often dysregulated in human cancer, including hepatocellular carcinoma (HCC). However, MYC is considered undruggable to date. Here, we comprehensively identify genes essential for the survival of MYC-high but not MYC-low cells by performing a CRISPR/Cas9 genome-wide screen in a MYC-conditional HCC model. Our screen identifies novel MYC-synthetic lethal interactions, as well as most previously identified MYC-synthetic lethal genes. In particular, we found genes involved in nuclear to cytoplasmic transport to be MYC-synthetic lethal in HCC, and we show that many of these genes are transcriptionally upregulated in MYC-high murine HCC.
Project description:Immunotherapy revolutionized the treatment of advanced melanoma. As the pathways mediating resistance to immunotherapy are largely unknown, we conducted transcriptome profiling of pre-immunotherapy tumor biopsies from melanoma patients that received PD-1 blockade (n=36) or adoptive cell therapy with tumor infiltrating lymphocytes (n=37). We identified two melanoma-intrinsic mutually exclusive gene programs, which are controlled by interferon-γ and MYC, and determine immunotherapy outcome. MYC-overexpressing melanoma cells exhibited lower interferon-γ responsiveness, which was linked with JAK2 downregulation. Luciferase activity assays under the control of JAK2 promoter demonstrated reduced activity in MYC-overexpressing cells, which was reversible upon mutagenesis of MYC E-box binding sites in the JAK2 promoter. Moreover, silencing of MYC or its co-factor MAX with siRNA increased JAK2 expression and interferon-γ responsiveness of melanomas, while concomitantly enhancing the effector functions of T-cells co-incubated with MYC-overexpressing cells. Thus, we propose that MYC plays a pivotal role in immunotherapy resistance through downregulation of JAK2.
Project description:The MYC oncogene is often dysregulated in human cancer, including hepatocellular carcinoma (HCC). However, MYC is considered undruggable to date. Here, we comprehensively identify genes essential for the survival of MYC-high but not MYC-low cells by performing a CRISPR/Cas9 genome-wide screen in a MYC-conditional HCC model. Our screen identifies novel MYC-synthetic lethal interactions, as well as most previously identified MYC-synthetic lethal genes. In particular, we found genes involved in nuclear to cytoplasmic transport to be MYC-synthetic lethal in HCC, and we show that many of these genes are transcriptionally upregulated in MYC-high murine HCC.
Project description:The MYC oncogene is often dysregulated in human cancer, including hepatocellular carcinoma (HCC). However, MYC is considered undruggable to date. Here, we comprehensively identify genes essential for the survival of MYC-high but not MYC-low cells by performing a CRISPR/Cas9 genome-wide screen in a MYC-conditional HCC model. Our screen identifies novel MYC-synthetic lethal interactions, as well as most previously identified MYC-synthetic lethal genes. In particular, we found genes involved in nuclear to cytoplasmic transport to be MYC-synthetic lethal in HCC, and we show that many of these genes are transcriptionally upregulated in MYC-high murine HCC.
Project description:Immunotherapy has opened hitherto unknown possibilities to treat cancer. Whereas some cancer types (e.g. melanoma) can be efficiently treated, others lack measurable positive effects (e.g. PDAC). Moreover, stratification of responders/non-responders is only possible in some cancer types (e.g. melanoma). Hepatocellular carcinoma (HCC) has a dismal prognosis, limited treatment options and survival benefit, and represents a potential cancer entity for successful immunotherapy. Here, we investigated NASH-triggered HCC in the context PD-1-targeted immunotherapy. Using flow cytometry, single cell RNA sequencing, immunohistochemistry and mass spectrometric analyses, we found a progressive increase of CD8+PD-1+ effector T-cells with a unique profile of exhaustion and activation markers rising with murine and human NASH severity. Notably, late-stage HCC treatment with PD-1-targeted immunotherapy enhanced hepatic carcinogenesis in mice. Dissecting potential mechanisms of action during tumor-initiation and -progression we analyzed the effects of PD-1-targeted immunotherapy at HCC initiation. PD-1-targeted immunotherapy induced a pro-tumorigenic environment, enhanced necro-inflammation and increased NAFLD-activation score (NAS), leading to increased liver cancer incidence, tumor number and nodule size. In contrast, anti-CD8 or anti-CD8/anti-NK1.1 treatment reduced NAS and abrogated the development of liver cancer, thus identifying CD8+PD-1+ T-cells as drivers of liver cancer in NASH-triggered HCC. Increased apoptotic signaling, STAT3 phosphorylation and hepatic proliferation were detected in intra-tumoral liver tissue upon PD-1-targeted immunotherapy. In line, PD-1-/- mice challenged with a NASH diet displayed early onset of hepatocarcinogenesis, corroborating the pro-tumorigenic role of absent or reduced PD-1. Mechanistically PD-1-targeted immunotherapy mainly affected hepatic abundance of CD8+PD-1+ T-cells, instead of altering the quality of Tox+CXCR6+ expressing CD8+PD-1+TNF+CD39+Gzmb+ T-cells found in NASH livers, leading to an aggressive, pro-tumorigenic liver environment. Single-cell mapping of human NASH-, borderline NASH- or unaffected livers corroborated our preclinical NASH results. Moreover, in human NASH livers a correlation of hepatic CD8+, PD-1+, TNF+ T-cells with fibrosis and NASH severity was observed. Accordingly, HCC patients with NASH etiology display a sharp increase in intra- and peri-tumoral CD8+ PD-1+ T-cells. In a cohort of 65 patients recruited across 6 centers in Germany and Austria, patients with NAFLD/NASH-driven HCC responded worse to PD-1-targeted immunotherapy by Nivolumab or Pembrolizumab compared to non-NAFLD patients. This resulted in significant reduced overall survival, in trends of faster disease progression and reduced progression free survival. Histological analysis of livers derived from HCC patients treated with PD-1-targeted immunotherapy displayed high levels of intra and peri-tumoral CD8+ PD-1+ T-cells and Ki67+ hepatocytes. Taken together, these data indicate that PD-1-targeted immunotherapy induces immune-related adverse effects in NAFLD/NASH-driven HCC through CD8+PD-1+ T-cells. Our data call for stratification of HCC patients subjected to PD-1-targeted immunotherapy, with NAFLD being a negative predictor.