40 research outputs found

    Castleman’s Disease presenting as a pleural mass in the thoracic cavity

    Get PDF
    A 61-year-old non-smoking Turkish woman presented with chest pain for 10 months. Computed tomography of the chest revealed a solitary, relatively well circumscribed, heterogeneous mass of 4 x 6 cm diameter in left posteriorlateral hemithorax. On thoracotomy, an extraparanchymal mass destructing the ribs was determined. Mass excision and partial chest wall resection were performed. On histopathologic examination, this mass showed features of the hyaline vascular type of Castleman’s Disease

    The Status of Antioxidants and Oxidative Damage in Patients with COVID-19

    Get PDF
    Purpose: COVID-19 is a viral disease that has recently caused a pandemic and significantly affects human health. In this study, superoxide dismutase, glutathione peroxidase, glutathione, total thiol, natural thiol, disulfide, oxidative DNA damage and malondialdehyde levels in COVID-19 were investigated. Materials and Methods: Thirty-five patients and 35 healthy volunteers were included in this study. The diagnosis of COVID-19 was made by reverse transcriptase-polymerase chain reaction. Serum glutathione, glutathione peroxidase, superoxide dismutase, natural thiol, total thiol and disulphide levels by enzyme-linked immunosorbent assay and malondialdehyde and 8-hydroxy-2-deoxyguanosine/10⁶ deoxyguanosine levels by high-pressure liquid chromatography measured. Results: While serum superoxide dismutase, glutathione peroxidase, malondialdehyde, 8-hydroxy-2-deoxyguanosine/10⁶ deoxyguanosine, disulfide levels were higher in the COVID-19 patient group than in the healthy control group, glutathione, total thiol, natural thiol levels were lower. In addition, there was a negative correlation between 8-hydroxy-2-deoxyguanosine/10⁶ deoxyguanosine and glutathione, natural thiol and total thiol, and a positive correlation with disulfide. Conclusion: This study revealed that serum superoxide dismutase, glutathione peroxidase, malondialdehyde, 8-hydroxy-2-deoxyguanosine/10⁶ deoxyguanosine, and disulfide levels increased and glutathione, thiol and natural thiol levels decreased in COVID-19 patients. These results revealed that there was a decrease in antioxidant marker levels and an increase in oxidative stress markers in COVID-19 patients

    Efficacy of BET bromodomain inhibition in Kras-mutant non-small cell lung cancer

    Get PDF
    PurposeAmplification of MYC is one of the most common genetic alterations in lung cancer, contributing to a myriad of phenotypes associated with growth, invasion and drug resistance. Murine genetics has established both the centrality of somatic alterations of Kras in lung cancer, as well as the dependency of mutant Kras tumors on MYC function. Unfortunately, drug-like small-molecule inhibitors of KRAS and MYC have yet to be realized. The recent discovery, in hematologic malignancies, that BET bromodomain inhibition impairs MYC expression and MYC transcriptional function established the rationale of targeting KRAS-driven NSCLC with BET inhibition.Experimental DesignWe performed functional assays to evaluate the effects of JQ1 in genetically defined NSCLC cells lines harboring KRAS and/or LKB1 mutations. Furthermore, we evaluated JQ1 in transgenic mouse lung cancer models expressing mutant kras or concurrent mutant kras and lkb1. Effects of bromodomain inhibition on transcriptional pathways were explored and validated by expression analysis.ResultsWhile JQ1 is broadly active in NSCLC cells, activity of JQ1 in mutant KRAS NSCLC is abrogated by concurrent alteration or genetic knock-down of LKB1. In sensitive NSCLC models, JQ1 treatment results in the coordinate downregulation of the MYC-dependent transcriptional program. We found that JQ1 treatment produces significant tumor regression in mutant kras mice. As predicted, tumors from mutant kras and lkb1 mice did not respond to JQ1.ConclusionBromodomain inhibition comprises a promising therapeutic strategy for KRAS mutant NSCLC with wild-type LKB1, via inhibition of MYC function. Clinical studies of BET bromodomain inhibitors in aggressive NSCLC will be actively pursued

    JAK2/IDH-mutant–driven myeloproliferative neoplasm is sensitive to combined targeted inhibition

    Get PDF
    Patients with myeloproliferative neoplasms (MPNs) frequently progress to bone marrow failure or acute myeloid leukemia (AML), and mutations in epigenetic regulators such as the metabolic enzyme isocitrate dehydrogenase (IDH) are associated with poor outcomes. Here, we showed that combined expression of Jak2V617Fand mutant IDH1R132Hor Idh2R140Q induces MPN progression, alters stem/progenitor cell function, and impairs differentiation in mice. Jak2V617FIdh2R140Q–mutant MPNs were sensitive to small-molecule inhibition of IDH. Combined inhibition of JAK2 and IDH2 normalized the stem and progenitor cell compartments in the murine model and reduced disease burden to a greater extent than was seen with JAK inhibition alone. In addition, combined JAK2 and IDH2 inhibitor treatment also reversed aberrant gene expression in MPN stem cells and reversed the metabolite perturbations induced by concurrent JAK2 and IDH2 mutations. Combined JAK2 and IDH2 inhibitor therapy also showed cooperative efficacy in cells from MPN patients with both JAK2mutand IDH2mutmutations. Taken together, these data suggest that combined JAK and IDH inhibition May offer a therapeutic advantage in this high-risk MPN subtype.Damon Runyon Cancer Research Foundation (DRG-2241-15)Howard Hughes Medical Institute (Faculty Scholars Award)Stand Up To CancerNational Cancer Institute (U.S.) (P50CA165962)National Cancer Institute (U.S.) (P30CA14051)Koch Institute for Integrative Cancer Research ( Dana-Farber Harvard Cancer Center Bridge Project)Leukemia & Lymphoma Society of America. Specialized Center of Research (SCOR) ProgramNational Institutes of Health (U.S.) (grant U54OD020355-01)National Institutes of Health (U.S.) (grant NCI R01CA172636)National Institutes of Health (U.S.) (grant R35CA197594)National Cancer Institute (U.S.) (Cancer Center Support Grant (P30 CA008747)

    AXL targeting restores PD-1 blockade sensitivity of STK11/LKB1 mutant NSCLC through expansion of TCF1+ CD8 T cells

    Get PDF
    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 in KPL tumors. This was observed in syngeneic immunocompetent mouse models and in humanized mice bearing STK11/LKB1 mutant NSCLC human tumor xenografts. NSCLC-affected individuals 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.publishedVersio

    \u3cem\u3eLkb1\u3c/em\u3e Inactivation Drives Lung Cancer Lineage Switching Governed by Polycomb Repressive Complex 2

    Get PDF
    Adenosquamous lung tumours, which are extremely poor prognosis, may result from cellular plasticity. Here, we demonstrate lineage switching of KRAS+ lung adenocarcinomas (ADC) to squamous cell carcinoma (SCC) through deletion of Lkb1 (Stk11) in autochthonous and transplant models. Chromatin analysis reveals loss of H3K27me3 and gain of H3K27ac and H3K4me3 at squamous lineage genes, including Sox2, ΔNp63 and Ngfr. SCC lesions have higher levels of the H3K27 methyltransferase EZH2 than the ADC lesions, but there is a clear lack of the essential Polycomb Repressive Complex 2 (PRC2) subunit EED in the SCC lesions. The pattern of high EZH2, but low H3K27me3 mark, is also prevalent in human lung SCC and SCC regions within ADSCC tumours. Using FACS-isolated populations, we demonstrate that bronchioalveolar stem cells and club cells are the likely cells-of-origin for SCC transitioned tumours. These findings shed light on the epigenetics and cellular origins of lineage-specific lung tumours

    Somatic LKB1 Mutations Promote Cervical Cancer Progression

    Get PDF
    Human Papilloma Virus (HPV) is the etiologic agent for cervical cancer. Yet, infection with HPV is not sufficient to cause cervical cancer, because most infected women develop transient epithelial dysplasias that spontaneously regress. Progression to invasive cancer has been attributed to diverse host factors such as immune or hormonal status, as no recurrent genetic alterations have been identified in cervical cancers. Thus, the pressing question as to the biological basis of cervical cancer progression has remained unresolved, hampering the development of novel therapies and prognostic tests. Here we show that at least 20% of cervical cancers harbor somatically-acquired mutations in the LKB1 tumor suppressor. Approximately one-half of tumors with mutations harbored single nucleotide substitutions or microdeletions identifiable by exon sequencing, while the other half harbored larger monoallelic or biallelic deletions detectable by multiplex ligation probe amplification (MLPA). Biallelic mutations were identified in most cervical cancer cell lines; HeLa, the first human cell line, harbors a homozygous 25 kb deletion that occurred in vivo. LKB1 inactivation in primary tumors was associated with accelerated disease progression. Median survival was only 13 months for patients with LKB1-deficient tumors, but >100 months for patients with LKB1-wild type tumors (P = 0.015, log rank test; hazard ratio = 0.25, 95% CI = 0.083 to 0.77). LKB1 is thus a major cervical tumor suppressor, demonstrating that acquired genetic alterations drive progression of HPV-induced dysplasias to invasive, lethal cancers. Furthermore, LKB1 status can be exploited clinically to predict disease recurrence

    Mutant IDH inhibits HNF-4α to block hepatocyte differentiation and promote biliary cancer

    Get PDF
    Mutations in isocitrate dehydrogenase 1 (IDH1) and IDH2 are among the most common genetic alterations in intrahepatic cholangiocarcinoma (IHCC), a deadly liver cancer1, 2, 3, 4, 5. Mutant IDH proteins in IHCC and other malignancies acquire an abnormal enzymatic activity allowing them to convert α-ketoglutarate (αKG) to 2-hydroxyglutarate (2HG), which inhibits the activity of multiple αKG-dependent dioxygenases, and results in alterations in cell differentiation, survival, and extracellular matrix maturation6, 7, 8, 9, 10. However, the molecular pathways by which IDH mutations lead to tumour formation remain unclear. Here we show that mutant IDH blocks liver progenitor cells from undergoing hepatocyte differentiation through the production of 2HG and suppression of HNF-4α, a master regulator of hepatocyte identity and quiescence. Correspondingly, genetically engineered mouse models expressing mutant IDH in the adult liver show an aberrant response to hepatic injury, characterized by HNF-4α silencing, impaired hepatocyte differentiation, and markedly elevated levels of cell proliferation. Moreover, IDH and Kras mutations, genetic alterations that co-exist in a subset of human IHCCs4, 5, cooperate to drive the expansion of liver progenitor cells, development of premalignant biliary lesions, and progression to metastatic IHCC. These studies provide a functional link between IDH mutations, hepatic cell fate, and IHCC pathogenesis, and present a novel genetically engineered mouse model of IDH-driven malignancy
    corecore