Project description:Sustained tumor progression has been attributed to a distinct population of tumor-propagating cells (TPCs). To identify TPCs relevant to lung cancer pathogenesis, we investigated functional heterogeneity in tumor cells isolated from Kras-driven mouse models of non-small cell lung cancer (NSCLC). CD24+ITGB4+Notchhi cells are capable of propagating tumor growth in both a clonogenic and an orthotopic serial transplantation assay. While all four Notch receptors mark TPCs, Notch3 plays a non-redundant role in tumor cell propagation in two mouse model and in human NSCLC. The TPC population is enriched after chemotherapy and the gene signature of mouse TPCs correlates with poor prognosis in human NSCLC. The unique role of Notch3 in tumor propagation may provide a therapeutic target for NSCLC Primary lung adenocarcinoma tumor cells were FACS sorted based on expression of CD24, ITGB4 and Notch. TPC cells are defined by Cd24+ITGB4+ Notch(high), and the remainder tumor cells are non-TPC cells. Samples were derived from six mice.
Project description:Sustained tumor progression has been attributed to a distinct population of tumor-propagating cells (TPCs). To identify TPCs relevant to lung cancer pathogenesis, we investigated functional heterogeneity in tumor cells isolated from Kras-driven mouse models of non-small cell lung cancer (NSCLC). CD24+ITGB4+Notchhi cells are capable of propagating tumor growth in both a clonogenic and an orthotopic serial transplantation assay. While all four Notch receptors mark TPCs, Notch3 plays a non-redundant role in tumor cell propagation in two mouse model and in human NSCLC. The TPC population is enriched after chemotherapy and the gene signature of mouse TPCs correlates with poor prognosis in human NSCLC. The unique role of Notch3 in tumor propagation may provide a therapeutic target for NSCLC Highly purified primary tumor cells were FACS sorted based on expression of CD24. Samples were derived from six mice.
Project description:Sustained tumor progression has been attributed to a distinct population of tumor-propagating cells (TPCs). To identify TPCs relevant to lung cancer pathogenesis, we investigated functional heterogeneity in tumor cells isolated from Kras-driven mouse models of non-small cell lung cancer (NSCLC). CD24+ITGB4+Notchhi cells are capable of propagating tumor growth in both a clonogenic and an orthotopic serial transplantation assay. While all four Notch receptors mark TPCs, Notch3 plays a non-redundant role in tumor cell propagation in two mouse model and in human NSCLC. The TPC population is enriched after chemotherapy and the gene signature of mouse TPCs correlates with poor prognosis in human NSCLC. The unique role of Notch3 in tumor propagation may provide a therapeutic target for NSCLC
Project description:Sustained tumor progression has been attributed to a distinct population of tumor-propagating cells (TPCs). To identify TPCs relevant to lung cancer pathogenesis, we investigated functional heterogeneity in tumor cells isolated from Kras-driven mouse models of non-small cell lung cancer (NSCLC). CD24+ITGB4+Notchhi cells are capable of propagating tumor growth in both a clonogenic and an orthotopic serial transplantation assay. While all four Notch receptors mark TPCs, Notch3 plays a non-redundant role in tumor cell propagation in two mouse model and in human NSCLC. The TPC population is enriched after chemotherapy and the gene signature of mouse TPCs correlates with poor prognosis in human NSCLC. The unique role of Notch3 in tumor propagation may provide a therapeutic target for NSCLC
Project description:Oncogenic STAT3 functions are known in various malignancies. We found that STAT3 plays an unexpected tumor suppressive role in KRAS-mutant non-small-cell-lung cancer (NSCLC). In mice, tissue-specific inactivation of Stat3 resulted in increased Kras (G12D)-driven NSCLC initiation and malignant progression leading to markedly reduced survival. Clinically, low STAT3 expression levels correlate with poor survival in human lung adenocarcinoma patients with smoking history. Consistently, KRAS-mutant lung tumors showed reduced STAT3 levels. Mechanistically, we show that STAT3 controls NFκB-induced IL-8-expression by sequestering NFκB in the cytoplasm while IL-8 in turn regulates myeloid tumor infiltration and tumor vascularization thereby promoting tumor progression. These results identify a novel STAT3-NFκB-IL-8 axis in KRAS-mutant NSCLC with therapeutic and prognostic relevance WT: Control lung; KRAS: Lung tumors expressing KRAS G12D; KRAS STAT3 KO: Lung tumors expressing KRAS G12D- STAT3 deficient; tumors of four mice pooled per sample
Project description:SOD1 is known as the major cytoplasmic superoxide dismutase and an anticancer target. However, the role of SOD1 in cancer is not fully understood. Herein we describe the generation of an inducible Sod1 knockout in KRAS-driven NSCLC mouse model. Sod1 knockout markedly reduces tumor burden in vivo and blocks growth of KRAS mutant NSCLC cells in vitro. Intriguingly, SOD1 is enriched in the nucleus and notably in the nucleolus of NSCLC cells. The nuclear and nucleolar, not cytoplasmic, form of SOD1 is essential for lung cancer cell proliferation. Moreover, SOD1 interacts with PeBoW complex and controls its assembly necessary for pre-60S ribosomal subunit maturation. Mechanistically, SOD1 regulates co-localization of PeBoW with and processing of pre-rRNA, and maturation of cytoplasmic 60S ribosomal subunits in KRAS mutant lung cancer cells. Collectively, our study unravels a nuclear SOD1 function essential for ribosome biogenesis and proliferation in KRAS-driven lung cancer.
Project description:Non-small cell lung cancer (NSCLC), the most frequent subtype of lung cancer, remains a highly lethal malignancy and one of the leading causes of cancer deaths worldwide. Mutant KRAS is the prevailing oncogenic driver of lung adenocarcinoma, the most common histological form of NSCLC. In this study, we examined the role of PKCe, an oncogenic kinase highly expressed in NSCLC and other cancers, in KRAS-driven tumorigenesis. Notably, database analysis revealed an association between PKCe expression and poor outcome in lung adenocarcinoma patients specifically having KRAS mutation. By generating a PKCe-deficient, conditionally activatable allele of oncogenic Kras (LSL-Kras G12D ;PKCe -/- mice) we were able to demonstrate the requirement of PKCe for Kras-driven lung tumorigenesis in vivo, which is consistent with the impaired transformed growth observed in PKCe-deficient KRAS-dependent NSCLC cells. Moreover, PKCe-knockout mice were found to be less susceptible to lung tumorigenesis induced by benzo[a]pyrene, a carcinogen that induces mutations in Kras. Mechanistic analysis using RNA-Seq revealed little overlapping for PKCe and KRAS in the control of genes/biological pathways relevant in NSCLC, suggesting that a permissive role of PKCe in KRAS-driven lung tumorigenesis may involve non-redundant mechanisms. Our results thus highlight the relevance and potential of targeting PKCe for lung cancer therapeutics.
Project description:Oncogenic STAT3 functions are known in various malignancies. We found that STAT3 plays an unexpected tumor suppressive role in KRAS-mutant non-small-cell-lung cancer (NSCLC). In mice, tissue-specific inactivation of Stat3 resulted in increased Kras (G12D)-driven NSCLC initiation and malignant progression leading to markedly reduced survival. Clinically, low STAT3 expression levels correlate with poor survival in human lung adenocarcinoma patients with smoking history. Consistently, KRAS-mutant lung tumors showed reduced STAT3 levels. Mechanistically, we show that STAT3 controls NFκB-induced IL-8-expression by sequestering NFκB in the cytoplasm while IL-8 in turn regulates myeloid tumor infiltration and tumor vascularization thereby promoting tumor progression. These results identify a novel STAT3-NFκB-IL-8 axis in KRAS-mutant NSCLC with therapeutic and prognostic relevance
Project description:Polycomb repressive complexes (PRC) are frequently implicated in human cancer acting either as oncogenes or tumor suppressors. Here we show that PRC2 is a critical regulator of Kras-driven non-small-cell lung cancer (NSCLC) progression. Modulation of PRC2 by either Ezh2 overexpression or Eed deletion enhances Kras-driven adenomagenesis and inflammation, respectively. Eed-loss-driven inflammation leads to massive macrophage recruitment and marked decline in tissue function. Additional Trp53 inactivation activates a cell autonomous epithelial-to-mesenchymal transition (EMT) program leading to an invasive mucinous adenocarcinoma. A switch between methylated/acetylated chromatin underlies the tumor phenotypic evolution, prominently involving genes controlled by Hippo/Wnt-signaling. Our observations in the mouse models were conserved in human cells. Importantly, PRC2 inactivation results in context-dependent phenotypic alterations, with implications for its therapeutic application. We generated ChIP-seq from primary Kras;p53 (KP) cells in culture with and without Eed (KPE) and from KP primary tumors generated by injection of NSCLC into the tail vein. Mice were sacrificed on the onset of shortness of breath. We generated genome-wide expression profiles (RNA-seq) and Nuclease Accessibility (NA)-seq in primary KP and KPE tumor cells. NA-seq was also performed in A549 cells.
Project description:As a master regulator of chromatin structure and function, the EZH2 lysine methyltransferase orchestrates transcriptional silencing of developmental gene networks. Overexpression of EZH2 is commonly observed in human epithelial cancers, such as non- small cell lung carcinoma (NSCLC), yet definitive demonstration of malignant transformation by deregulated EZH2 has proven elusive. Here, we demonstrate the causal role of EZH2 overexpression in NSCLC with a new genetically-engineered mouse model of lung adenocarcinoma. Deregulated EZH2 silences normal developmental pathways leading to epigenetic transformation independent from canonical growth factor pathway activation. As such, tumors feature a transcriptional program distinct from KRAS- and EGFR-mutant mouse lung cancers, but shared with human lung adenocarcinomas exhibiting high EZH2 expression. To target EZH2-dependent cancers, we developed a novel and potent EZH2 inhibitor that arises from a facile synthesis and possesses improved pharmacologic properties. JQEZ5 promoted the regression of EZH2-driven tumors in vivo, confirming oncogenic addiction to EZH2 in established tumors and providing the rationale for epigenetic therapy in a defined subset of lung cancer. ChIP-Seq for H3K27ac and H3K27me3 in murine normal and EZH2 overexpressed tumor lung tissue