Project description:We performed RNA-sequencing of mouse cells derived from colony forming assays (CFA) to evaluate the transcriptome of MPN cells with deletion of the tumor suppressor STK11/LKB1 and relative controls. The CFA are from mouse primary floxed STK11 hematopoietic stem and progenitor cells (HSPCs) transduced with retroviruses encoding the MPN mutation MPLW515L and CRE recombinase to delete STK11.
Project description:The myeloproliferative neoplasms (MPN) frequently progress to blast phase disease, an aggressive form of acute myeloid leukemia. To identify genes that suppress disease progression, we performed a focused CRISPR/Cas9 screen and discovered that depletion of LKB1/Stk11 led to enhanced in vitro self-renewal of murine MPN cells. Deletion of Stk11 in a mouse MPN model caused rapid lethality with enhanced fibrosis, osteosclerosis, and an accumulation of immature cells in the bone marrow, as well as enhanced engraftment of primary human MPN cells in vivo. LKB1 loss was associated with increased mitochondrial reactive oxygen species and stabilization of HIF1α, and downregulation of LKB1 and increased levels of HIF1α were observed in human blast phase MPN specimens. Of note, we observed strong concordance of pathways that were enriched in murine MPN cells with LKB1 loss with those enriched in blast phase MPN patient specimens, supporting the conclusion that STK11 is a tumor suppressor in the MPNs.
Project description:We investigated how selective mutation in STK11 or KEAP1 alters the transcriptional profile of cancer cells, and how the transcriptional profile of co-mutant cells might uniquely affect cancer-related pathways including control of proliferative potential, metabolic homeostasis, and cell death. We performed bulk RNAseq on none, single or double mutation of these genes in single cell knockout clones (n=3 per group) from both H358 and H292 cell lines.
Project description:Transcriptional profiling of BL/6 mice harboring a mutant Kras allele, with or without knockouts of Stk11 and/or Keap1, or with expression of an Nfe2l2 transgene, Nrf2Tg. In lung adenocarcinoma (LUAD), stabilization of the transcription factor NRF2 through genomic alterations in KEAP1 and NFE2L2 occurs in roughly a quarter of patients, often in the context of STK11 tumor suppressor loss. In this study, we demonstrate that NRF2 activation in the context of concurrent KRAS mutation and STK11 loss promotes aggressive LUAD tumor behavior in both human and mouse preclinical models. This phenotype is associated with metabolic rewiring and rescue by NRF2 of redox stress, high in STK11 null tumors. Applying a novel, pan-lung cancer, diagnostic NRF2 activation gene expression signature that is independent of frequently co-occurring mutations, we dissect the independent contributions of the three most frequent genetic events in human LUAD (NRF2 activation, STK11 loss and KRAS mutations) on patient prognosis and clinical responses in a dataset of second-line LUAD patients treated with immunotherapy or chemotherapy (OAK trial). Our findings underscore that both individual effects and epistatic relationships among oncogenic and tumor suppressor pathways influence tumor biology, immune contexture and patient clinical outcomes. Our work also highlights the value of lung cancer disease sub-classification based on genetic and expression profiling as part of patient clinical management.
Project description:HCC515 lung cells with dox-inducible KEAP1 knockdown and/or STK11 re-addition, under two different metabolic stress conditions, baseline vs. suspension, were transcriptionally profiled to investigate whether KEAP1 knockdown can rescue metabolic defects in STK11-null cancer cells and how the regulation of the transcriptome by KEAP1 knockdown is affected by STK11 status and different metabolic stress conditions. In lung adenocarcinoma (LUAD), stabilization of the transcription factor NRF2 through genomic alterations in KEAP1 and NFE2L2 occurs in roughly a quarter of patients, often in the context of STK11 tumor suppressor loss. In this study, we demonstrate that NRF2 activation in the context of concurrent KRAS mutation and STK11 loss promotes aggressive LUAD tumor behavior in both human and mouse preclinical models. This phenotype is associated with metabolic rewiring and rescue by NRF2 of redox stress, high in STK11 null tumors. Applying a novel, pan-lung cancer, diagnostic NRF2 activation gene expression signature that is independent of frequently co-occurring mutations, we dissect the independent contributions of the three most frequent genetic events in human LUAD (NRF2 activation, STK11 loss and KRAS mutations) on patient prognosis and clinical responses in a dataset of second-line LUAD patients treated with immunotherapy or chemotherapy (OAK trial). Our findings underscore that both individual effects and epistatic relationships among oncogenic and tumor suppressor pathways influence tumor biology, immune contexture and patient clinical outcomes. Our work also highlights the value of lung cancer disease sub-classification based on genetic and expression profiling as part of patient clinical management.
Project description:Philadelphia-chromosome negative myeloproliferative neoplasms (MPNs) including polycythemia vera, essential thrombocythemia and primary myelofibrosis show an inherent tendency for transformation into leukemia (MPN-blast phase), which is hypothesized to be accompanied by acquisition of additional genomic lesions. We, therefore, examined chromosomal abnormalities by high-resolution single-nucleotide polymorphism (SNP) array in 88 MPN patients, as well as 71 cases with MPN-blast phase, and correlated these findings with their clinical parameters. Frequent genomic alterations were found in MPN after leukemic transformation with up to 3-fold more genomic changes per sample compared to samples in chronic phase (p<0.001). We identified commonly altered regions involved in disease progression including established targets (ETV6, TP53 and RUNX1), as well as new candidate genes on 7q, 16q, 19p and 21q. Moreover, trisomy 8 or amplification of 8q24 (MYC) was almost exclusively detected in JAK2V617F(-) cases with MPN-blast phase. Remarkably, copy-number neutral-loss of heterozygosity (CNN-LOH) on either 7q or 9p including homozygous JAK2V617F was related to decreased survival after leukemic transformation (p=0.01 and p=0.016, respectively). Our high density SNP-array analysis of MPN genomes in the chronic compared to leukemic stage identified novel target genes and provided prognostic insights associated with the evolution to leukemia. Keywords: SNP-chip To identify oncogenic lesions in MPD, we performed a genome-wide analysis of primary MPD samples using high-density SNP arrays (Affymetrix GeneChip).
Project description:Mutations in STK11/LKB1 in non-small cell lung cancer (NSCLC) are associated with poor patient responses to immune checkpoint blockade (ICB) and introduction of a Stk11/Lkb1 (L) mutation into murine lung adenocarcinomas driven by mutant Kras and Trp53 loss (KP) resulted in an ICB refractory syngeneic KPL tumor. Mechanistically this occurred because KPL mutant NSCLCs lacked TCF1-expressing CD8 T cells, a phenotype recapitulated in human STK11/LKB1 mutant NSCLCs. Systemic inhibition of Axl results in increased type I interferon secretion from dendritic cells that expanded tumor-associated TCF1+ PD-1+ CD8 T cells, restoring therapeutic response to PD-1 ICB for KPL tumors. This was observed in syngeneic immunocompetent mouse models and in humanized mice bearing STK11/LKB1 mutant NSCLC human tumor xenografts. NSCLC patients with identified STK11/LKB1 mutations receiving bemcentinib and pembrolizumab demonstrated objective clinical response to combination therapy. We conclude that AXL is a critical targetable driver of immune suppression in STK11/LKB1 mutant NSCLC.
Project description:Genomic DNA of granulocytes or mononuclear cell fractions of 408 myeloproliferative neoplasm (MPN) patients was analyzed using Affymetrix Genome-Wide Human SNP 6.0 arrays
Project description:While mutations in the KRAS oncogene are amongst the most prevalent in human cancer, there are few successful treatments to target these tumors. It is also likely that heterogeneity in KRAS-mutant tumor biology significantly contributes to the response to therapy. We hypothesized that presence of commonly co-occurring mutations in STK11 and TP53 tumor suppressors may represent a significant source of heterogeneity in KRAS-mutant tumors. To address this, we utilized a large cohort of resected tumors from 442 lung adenocarcinoma patients with data including annotation of prevalent driver mutations (KRAS, EGFR) and tumor suppressor mutations (STK11 and TP53), microarray-based gene expression and clinical covariates including overall survival (OS). Specifically, we determined impact of STK11 and TP53 mutations on a new KRAS mutation-associated gene expression signature as well as previously defined signatures of tumor cell proliferation and immune surveillance responses. Interestingly, STK11, but not TP53 mutations, were associated with highly elevated expression of KRAS mutation-associated genes. Mutations in TP53 and STK11 also impacted tumor biology regardless of KRAS status, with TP53 strongly associated with enhanced proliferation and STK11 with suppression of immune surveillance. These findings illustrate the remarkably distinct ways through which tumor suppressor mutations may contribute to heterogeneity in KRAS-mutant tumor biology. In addition, these studies point to novel associations between gene mutations and immune surveillance that could impact the response to immunotherapy.
Project description:Philadelphia-chromosome negative myeloproliferative neoplasms (MPNs) including polycythemia vera, essential thrombocythemia and primary myelofibrosis show an inherent tendency for transformation into leukemia (MPN-blast phase), which is hypothesized to be accompanied by acquisition of additional genomic lesions. We, therefore, examined chromosomal abnormalities by high-resolution single-nucleotide polymorphism (SNP) array in 88 MPN patients, as well as 71 cases with MPN-blast phase, and correlated these findings with their clinical parameters. Frequent genomic alterations were found in MPN after leukemic transformation with up to 3-fold more genomic changes per sample compared to samples in chronic phase (p<0.001). We identified commonly altered regions involved in disease progression including established targets (ETV6, TP53 and RUNX1), as well as new candidate genes on 7q, 16q, 19p and 21q. Moreover, trisomy 8 or amplification of 8q24 (MYC) was almost exclusively detected in JAK2V617F(-) cases with MPN-blast phase. Remarkably, copy-number neutral-loss of heterozygosity (CNN-LOH) on either 7q or 9p including homozygous JAK2V617F was related to decreased survival after leukemic transformation (p=0.01 and p=0.016, respectively). Our high density SNP-array analysis of MPN genomes in the chronic compared to leukemic stage identified novel target genes and provided prognostic insights associated with the evolution to leukemia. Keywords: SNP-chip