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2.
bioRxiv ; 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37662289

RESUMO

Metastasis is the principal cause of cancer death, yet we lack an understanding of metastatic cell states, their relationship to primary tumor states, and the mechanisms by which they transition. In a cohort of biospecimen trios from same-patient normal colon, primary and metastatic colorectal cancer, we show that while primary tumors largely adopt LGR5 + intestinal stem-like states, metastases display progressive plasticity. Loss of intestinal cell states is accompanied by reprogramming into a highly conserved fetal progenitor state, followed by non-canonical differentiation into divergent squamous and neuroendocrine-like states, which is exacerbated by chemotherapy and associated with poor patient survival. Using matched patient-derived organoids, we demonstrate that metastatic cancer cells exhibit greater cell-autonomous multilineage differentiation potential in response to microenvironment cues than their intestinal lineage-restricted primary tumor counterparts. We identify PROX1 as a stabilizer of intestinal lineage in the fetal progenitor state, whose downregulation licenses non-canonical reprogramming.

3.
Scand J Immunol ; 62(2): 123-30, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16101818

RESUMO

The development of pulmonary granulomatous lesions during mycobacterial infection is a complex phenomenon, in part caused by responses elicited towards the surface glycolipid trehalose 6,6'-dimycolate (TDM; cord factor). The molecular mechanisms underlying granuloma formation following challenge with TDM are not yet completely understood. The present study defines pathologic differences in acute response to Mycobacterium tuberculosis TDM in C57BL/6 mice and mice lacking the C5a receptor (C5aR-/-). Mice were intravenously injected with TDM prepared in water-in-oil-in-water emulsion and examined for histologic response and changes in proinflammatory cytokines and chemokines in lung tissue. Control C5a receptor-sufficient mice demonstrated a granulomatous response that peaked between days 4 and 7. Increased production of macrophage inflammatory protein-1 alpha (MIP-1alpha), interleukin-1beta (IL-1beta) and CXC chemokine KC (CXCL1) correlated with development of granulomas, along with modest change in tumor necrosis factor-alpha (TNF-alpha). In contrast, the C5aR-/- mice revealed markedly exacerbated inflammatory response. The receptor-deficient mice also demonstrated a lack of coherent granulomatous response, with severe oedema present and instances of lymphocytic cuffing around pulmonary vessels. Lung weight index was increased in the C5aR-/- mice, correlating with increased MIP-1alpha, KC, IL-1beta and TNF-alpha over that identified in the congenic C5aR-sufficient controls. Correlate experiments performed in C5-deficient (B10.D2-H2d H2-T18c Hco/oSnJ) mice revealed similar results, leading to the conclusion that C5 plays a significant role in mediation of chemotactic and activation events that are the basis for maturation of granulomatous responses to TDM.


Assuntos
Complemento C5/imunologia , Fatores Corda/imunologia , Granuloma/imunologia , Mycobacterium tuberculosis/imunologia , Receptor da Anafilatoxina C5a/imunologia , Tuberculose/imunologia , Animais , Quimiocina CCL3 , Quimiocina CCL4 , Quimiocina CXCL1 , Quimiocinas CXC/metabolismo , Histocitoquímica , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Interleucina-1/metabolismo , Proteínas Inflamatórias de Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Tuberculose/patologia , Fator de Necrose Tumoral alfa/metabolismo
4.
J Immunol ; 165(10): 5406-9, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11067891

RESUMO

The complement anaphylatoxin C3a, on binding the C3aR, mediates numerous proinflammatory activities. In addition, recent in vitro studies with C3a have implicated C3aR as a possible anti-inflammatory receptor. Because of its possible dual role in modulating the inflammatory response, it is uncertain whether C3aR contributes to the pathogenesis of endotoxin shock. Here, the targeted-disruption of the C3aR in mice is reported. These mice exhibit an enhanced lethality to endotoxin shock with a pronounced gene dosage effect. In addition, the plasma concentration of IL-1beta was significantly elevated in the C3aR(-/-) mice compared with their littermates following LPS challenge. These findings demonstrate an important protective role for the C3aR in endotoxin shock and indicate that, in addition to its traditionally accepted functions in mediating inflammation, the C3aR also acts in vivo as an anti-inflammatory receptor by attenuating LPS-induced proinflammatory cytokine production.


Assuntos
Anti-Inflamatórios não Esteroides/imunologia , Complemento C3a/fisiologia , Marcação de Genes , Proteínas de Membrana , Receptores de Complemento/genética , Choque Séptico/genética , Choque Séptico/imunologia , Sequência de Aminoácidos , Animais , Complemento C3a/metabolismo , Relação Dose-Resposta Imunológica , Marcação de Genes/métodos , Predisposição Genética para Doença , Injeções Intravenosas , Interleucina-1/biossíntese , Interleucina-1/sangue , Lipopolissacarídeos/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Dados de Sequência Molecular , Mutagênese Insercional , Receptores de Complemento/deficiência , Choque Séptico/mortalidade
5.
Mol Immunol ; 35(3): 137-48, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9694514

RESUMO

The complement C3a anaphylatoxin receptor (C3aR) is a seven-transmembrane G-protein coupled chemoattractant receptor that on binding the C3a peptide ligand mediates numerous cellular responses, including histamine release from mast cells. smooth muscle contraction, and the directed migration of eosinophils. To delineate the murine C3aR coding sequence, gene structure, 5'-flanking region, and chromosome location, cDNA and genomic clones encoding the mouse C3a receptor were isolated, characterized, and used in fluorescence in situ hybridization experiments. The results from this study indicate that the murine C3a receptor structural gene is a single copy gene of approximately 8 kb comprised of 2 exons which are separated by a large intervening intron of 4724 bp. The first exon encodes 97 bp of 5'-untranslated sequence. Exon 2 encodes the remaining 8 bp of 5'-untranslated sequence and the entire coding and 3'-untranslated sequences. This genomic organization is typical of most other chemoattractant receptor genes in that the entire coding sequence is contained on a single exon. The human and mouse C3a receptor genes were localized to syntenic chromosomal bands 12q13.2-3 and 6F1, respectively. No other seven-transmembrane receptor genes, to date, have been localized to these chromosomal regions. Primer extension experiments using mouse macrophage RNA indicated a single transcriptional initiation site. Sequence analysis 5' of the transcriptional site indicated a TATA-less promoter with possible cis-acting motifs that may regulate C3a receptor gene expression. These included the recognition sequence for the nuclear transcription factor SP1 and the phorbol ester response sequence which binds the Fos/Jun heteromeric transcription factor AP1.


Assuntos
Complemento C3a/metabolismo , Proteínas de Membrana , Receptores de Complemento/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Ligação Competitiva , Mapeamento Cromossômico , Cromossomos Humanos Par 12/genética , Clonagem Molecular , DNA Complementar/genética , Expressão Gênica , Genes , Humanos , Hibridização in Situ Fluorescente , Macrófagos/imunologia , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Estrutura Secundária de Proteína , Receptores de Complemento/química , Receptores de Complemento/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Transfecção
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