RESUMO
OBJECTIVE: Oesophageal cancer (OEC) is an aggressive disease with a poor survival rate. Prognostic markers are thus urgently needed. Due to the demonstrated prognostic value of histopathological growth pattern (HGP) in other cancers, we performed a retrospective assessment of HGP in patients suffering from invasive OEC. DESIGN: A first cohort composed of 89 treatment-naïve operated patients with OEC from The Cancer Genome Atlas (TCGA) public database was constituted, from which H&E images and RNA-sequencing data were retrieved. Next, a second cohort composed of 99 patients with OEC treated and operated in a Belgian hospital was established. H&E-stained sections and extracted tumorous RNA were obtained from the samples. HGP were assessed on H&E slides as infiltrative (IGP) or expansive (EGP). TCGA RNA-sequencing data were analysed through the gene set enrichment analysis and Cytoscape softwares. Real-time quantitative PCR (qPCR) experiments were performed to assess gene expression in the Belgian cohort. RESULTS: IGP patients displayed a grim prognosis compared with EGP patients, while IGP was found as associated with numerous lymphovascular emboli and perinervous infiltrations. Analyses of the TCGA expression data showed that angiogenesis, epithelial-to-mesenchymal transition (EMT) and inflammation were significantly upregulated in IGP compared with EGP samples. qPCR experiments of three genes appearing as highly upregulated in each pathway showed no difference in expression according to the HGP. CONCLUSION: The current study demonstrates the poor prognostic value carried by IGP in OC and suggests angiogenesis, EMT and inflammation as key carcinogenetic pathways upregulated in this pattern.
Assuntos
Proliferação de Células/genética , Neoplasias Esofágicas/genética , Invasividade Neoplásica/genética , Adenocarcinoma/patologia , Idoso , Bélgica/epidemiologia , Carcinoma de Células Escamosas/patologia , Estudos de Coortes , Gerenciamento de Dados , Transição Epitelial-Mesenquimal/genética , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Inflamação/genética , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Estudos Retrospectivos , Análise de Sequência de RNA/métodos , Regulação para CimaRESUMO
Apple (Malus × domestica) accumulates bioactive ursane-, oleanane-, and lupane-type triterpenes in its fruit cuticle, but their biosynthetic pathway is still poorly understood. We used a homology-based approach to identify and functionally characterize two new oxidosqualene cyclases (MdOSC4 and MdOSC5) and one cytochrome P450 (CYP716A175). The gene expression patterns of these enzymes and of previously described oxidosqualene cyclases were further studied in 20 apple cultivars with contrasting triterpene profiles. MdOSC4 encodes a multifunctional oxidosqualene cyclase producing an oleanane-type triterpene, putatively identified as germanicol, as well as ß-amyrin and lupeol, in the proportion 82 : 14 : 4. MdOSC5 cyclizes 2,3-oxidosqualene into lupeol and ß-amyrin at a ratio of 95 : 5. CYP716A175 catalyses the C-28 oxidation of α-amyrin, ß-amyrin, lupeol and germanicol, producing ursolic acid, oleanolic acid, betulinic acid, and putatively morolic acid. The gene expression of MdOSC1 was linked to the concentrations of ursolic and oleanolic acid, whereas the expression of MdOSC5 was correlated with the concentrations of betulinic acid and its caffeate derivatives. Two new multifuntional triterpene synthases as well as a multifunctional triterpene C-28 oxidase were identified in Malus × domestica. This study also suggests that MdOSC1 and MdOSC5 are key genes in apple fruit triterpene biosynthesis.
Assuntos
Vias Biossintéticas , Sistema Enzimático do Citocromo P-450/metabolismo , Frutas/enzimologia , Transferases Intramoleculares/metabolismo , Malus/enzimologia , Triterpenos/metabolismo , Sequência de Aminoácidos , Vias Biossintéticas/genética , Clonagem Molecular , Frutas/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Malus/genética , Filogenia , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Análise de Componente Principal , Alinhamento de Sequência , Análise de Sequência de Proteína , Esqualeno/análogos & derivados , Esqualeno/química , Esqualeno/metabolismo , Nicotiana/genética , Triterpenos/químicaRESUMO
Russeting, a commercially important defect in the exocarp of apple (Malus × domestica), is mainly characterized by the accumulation of suberin on the inner part of the cell wall of the outer epidermal cell layers. However, knowledge on the underlying genetic components triggering this trait remains sketchy. Bulk transcriptomic profiling was performed on the exocarps of three russeted and three waxy apple varieties. This experimental design was chosen to lower the impact of genotype on the obtained results. Validation by qPCR was carried out on representative genes and additional varieties. Gene ontology enrichment revealed a repression of lignin and cuticle biosynthesis genes in russeted exocarps, concomitantly with an enhanced expression of suberin deposition, stress responsive, primary sensing, NAC and MYB-family transcription factors, and specific triterpene biosynthetic genes. Notably, a strong correlation (R(2) = 0.976) between the expression of a MYB93-like transcription factor and key suberin biosynthetic genes was found. Our results suggest that russeting is induced by a decreased expression of cuticle biosynthetic genes, leading to a stress response which not only affects suberin deposition, but also the entire structure of the cell wall. The large number of candidate genes identified in this study provides a solid foundation for further functional studies.
