RESUMO
BACKGROUND: The overexpression of microRNA-21 (miR-21) in pancreatic cancer has been implicated in drug resistance to gemcitabine. Thus far, miR-21 has gained wide attention as a potential biomarker to predict the clinical response in patients with pancreatic cancer receiving gemcitabine. The aim of this study was to evaluate the predictive value of miR-21 expression, determined by locked nucleic acid in situ hybridization (LNA-ISH), in patients with pancreatic cancer who underwent adjuvant gemcitabine after curative surgery. MATERIALS AND METHODS: Tumor miR-21 expression was analyzed via LNA-ISH and correlated with the clinical outcomes of the patients treated with adjuvant gemcitabine. RESULTS: The overexpression of miR-21 in pancreatic cancer, determined by LNA-ISH, was significantly and independently associated with a shorter disease-free survival in patients who received adjuvant gemcitabine after curative resection. CONCLUSION: The LNA-ISH analysis of miR-21 may serve as a significant predictor for gemcitabine resistance in patients with pancreatic cancer undergoing adjuvant gemcitabine after curative resection.
Assuntos
Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/cirurgia , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , MicroRNAs/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/cirurgia , Idoso , Carcinoma Ductal Pancreático/genética , Quimioterapia Adjuvante , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Feminino , Humanos , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Oligonucleotídeos/genética , Neoplasias Pancreáticas/genética , Prognóstico , Análise de Sobrevida , Resultado do Tratamento , GencitabinaRESUMO
We have previously shown that maturation of mouse bone marrow-derived mast cells (BMMCs) into connective tissue mast cells (CTMCs) upon coculture with fibroblasts in the presence of stem cell factor (kit ligand) is accompanied by marked induction of a panel of genes, one of which was identified as NLRP3. Here we report that NLRP3 acts as a novel negative regulator of delayed prostaglandin (PG) D(2) production in BMMCs. We found that, apart from its cell maturation-associated induction, NLRP3 expression was markedly induced in BMMCs several hours after FcepsilonRI crosslinking or cytokine stimulation. Ectopic expression of NLRP3 in BMMCs resulted in marked attenuation of cyclooxygenase (COX)-2-dependent delayed PGD(2) generation, whereas it had no effects on other effector functions, including degranulation, COX-1-dependent immediate PGD(2) generation and cytokine/chemokine expression. The suppression of delayed PGD(2) generation by NLRP3 was preceded by a transient decrease of NF-kappaB activation and a marked reduction in the expression of COX-2, but not that of cytosolic phospholipase A(2) alpha (cPLA(2)alpha), COX-1 and hematopoietic PGD(2) synthase. Moreover, in CTMC-like differentiated cells in which endogenous NLRP3 expression was induced, cytokine-stimulated induction of COX-2 and attendant delayed PGD(2) generation were markedly reduced. Our results suggest that, in mouse mast cells, NLRP3 counter-regulates COX-2-dependent sustained production of PGD(2), a prostanoid that exhibits both pro- and anti-allergic effects, thereby potentially influencing the duration of allergic and other mast cell-associated inflammatory diseases.
Assuntos
Proteínas de Transporte/metabolismo , Mastócitos/metabolismo , Prostaglandina D2/biossíntese , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular , Mastócitos/citologia , Mastócitos/enzimologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLRRESUMO
Coculture of mouse bone marrow-derived immature mast cells (BMMC) with Swiss 3T3 fibroblasts in the presence of stem cell factor (SCF) promotes morphological and functional maturation toward a connective tissue mast cell (CTMC)-like phenotype, which is accompanied by increased expression of several unique genes. Here we report the molecular identification of one of them, mast cell maturation-associated inducible gene (MMIG)-1. The MMIG-1 cDNA encodes a 117-kDa cytosolic protein that comprises an N-terminal PYRIN domain, a central nucleotide-binding domain, and nine C-terminal leucine-rich repeats. MMIG-1 shows >85% sequence similarity to human cryopyrin/PYPAF1, a causal gene for familial cold urticaria and Muckle-Wells syndrome. MMIG-1 was distributed in the cytosol of CTMC-like differentiated BMMC. MMIG-1 underwent alternative splicing in the leucine-rich repeats and each variant was induced differently in BMMC during coculture. Moreover, its expression was increased in the ears of mice with experimental atopic dermatitis. Thus, MMIG-1, a likely mouse PYPAF1 ortholog, may play a role in mast cell-directed inflammatory diseases.
