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RATIONALE AND OBJECTIVES: Transarterial chemoembolization (TACE) plus molecular targeted therapies has emerged as the main approach for treating hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). A robust model for outcome prediction and risk stratification of recommended TACE plus molecular targeted therapies candidates is lacking. We aimed to develop an easy-to-use tool specifically for these patients. METHODS: A retrospective analysis was conducted on 384 patients with HCC and PVTT who underwent TACE plus molecular targeted therapies at 16 different institutions. We developed and validated a new prognostic score which called ABPS score. Additionally, an external validation was performed on data from 200 patients enrolled in a prospective cohort study. RESULTS: The ABPS score (ranging from 0 to 3 scores), which involves only Albumin-bilirubin (ALBI, grade 1: 0 score; grade 2: 1 score), PVTT(I-II type: 0 score; III-IV type: 1 score), and systemic-immune inflammation index (SII,<550 × 1012: 0 score; ≥550 × 1012: 1 score). Patients were categorized into three risk groups based on their ABPS score: ABPS-A, B, and C (scored 0, 1-2, and 3, respectively). The concordance index (C-index) of the ABPS scoring system was calculated to be 0.802, significantly outperforming the HAP score (0.758), 6-12 (0.712), Up to 7 (0.683), and ALBI (0.595) scoring systems (all P < 0.05). These research findings were further validated in the external validation cohorts. CONCLUSION: The ABPS score demonstrated a strong association with survival outcomes and radiological response in patients undergoing TACE plus molecular targeted therapy for HCC with PVTT. The ABPS scoring system could serve as a valuable tool to guide treatment selection for these patients.
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RNA silencing is an important mechanism to regulate gene expression and antiviral defense in plants. Nevertheless, RNA silencing machinery in the important oil crop Brassica napus and function in resistance to the devastating fungal pathogen Sclerotinia sclerotiorum are not well-understood. In this study, gene families of RNA silencing machinery in B. napus were identified and their role in resistance to S. sclerotiorum was revealed. Genome of the allopolyploid species B. napus possessed 8 Dicer-like (DCL), 27 Argonaute (AGO), and 16 RNA-dependent RNA polymerase (RDR) genes, which included almost all copies from its progenitor species B. rapa and B. oleracea and three extra copies of RDR5 genes, indicating that the RDR5 group in B. napus appears to have undergone further expansion through duplication during evolution. Moreover, compared with Arabidopsis, some AGO and RDR genes such as AGO1, AGO4, AGO9, and RDR5 had significantly expanded in these Brassica species. Twenty-one out of 51 DCL, AGO, and RDR genes were predicted to contain calmodulin-binding transcription activators (CAMTA)-binding site (CGCG box). S. sclerotiorum inoculation strongly induced the expression of BnCAMTA3 genes while significantly suppressed that of some CGCG-containing RNA silencing component genes, suggesting that RNA silencing machinery might be targeted by CAMTA3. Furthermore, Arabidopsis mutant analyses demonstrated that dcl4-2, ago9-1, rdr1-1, rdr6-11, and rdr6-15 mutants were more susceptible to S. sclerotiorum, while dcl1-9 was more resistant. Our results reveal the importance of RNA silencing in plant resistance to S. sclerotiorum and imply a new mechanism of CAMTA function as well as RNA silencing regulation.
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MicroRNAs (miRNAs) are multifunctional non-coding short nucleotide molecules. Nevertheless, the role of miRNAs in the interactions between plants and necrotrophic pathogens is largely unknown. Here, we report the identification of the miRNA repertoire of the economically important oil crop oilseed rape (Brassica napus) and those involved in interacting with its most devastating necrotrophic pathogen Sclerotinia sclerotiorum. We identified 280 B. napus miRNA candidates, including 53 novel candidates and 227 canonical members or variants of known miRNA families, by high-throughput deep sequencing of small RNAs from both normal and S. sclerotiorum-inoculated leaves. Target genes of 15 novel candidates and 222 known miRNAs were further identified by sequencing of degradomes from the two types of samples. MiRNA microarray analysis revealed that 68 miRNAs were differentially expressed between S. sclerotiorum-inoculated and uninoculated leaves. A set of these miRNAs target genes involved in plant defense to S. sclerotiorum and/or other pathogens such as nucleotide binding site-leucine-rich repeat (NBS-LRR) R genes and nitric oxygen and reactive oxygen species related genes. Additionally, three miRNAs target AGO1 and AGO2, key components of post-transcriptional gene silencing (PTGS). Expression of several viral PTGS suppressors reduced resistance to S. sclerotiorum. Arabidopsis mutants of AGO1 and AGO2 exhibited reduced resistance while transgenic lines over-expressing AGO1 displayed increased resistance to S. sclerotiorum in an AGO1 expression level-dependent manner. Moreover, transient over-expression of miRNAs targeting AGO1 and AGO2 decreased resistance to S. sclerotiorum in oilseed rape. Our results demonstrate that the interactions between B. napus and S. sclerotiorum are tightly regulated at miRNA level and probably involve PTGS.
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Ascomicetos/patogenicidad , Brassica napus/genética , Brassica napus/microbiología , MicroARNs/genética , Plantas Modificadas Genéticamente/microbiología , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/microbiología , Brassica napus/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Plantas Modificadas Genéticamente/genéticaRESUMEN
Identification of hypersensitive cell death (HCD) regulators is essential to dissect the molecular mechanisms underlying plant disease resistance. In this study, combined proteomic and RNA interfering (RNAi) analyses were employed to identify genes required for the HCD conferred by the tomato resistance gene Cf-4 and the Cladosporium fulvum avirulence gene Avr4. Forty-nine proteins differentially expressed in the tomato seedlings mounting and those not mounting Cf-4/Avr4-dependent HCD were identified through proteomic analysis. Among them were a variety of defence-related proteins including a cysteine protease, Pip1, an operative target of another C. fulvum effector, Avr2. Additionally, glutathione-mediated antioxidation is a major response to Cf-4/Avr4-dependent HCD. Functional analysis through tobacco rattle virus-induced gene silencing and transient RNAi assays of the chosen 16 differentially expressed proteins revealed that seven genes, which encode Pip1 homologue NbPip1, a SIPK type MAP kinase Nbf4, an asparagine synthetase NbAsn, a trypsin inhibitor LeMir-like protein NbMir, a small GTP-binding protein, a late embryogenesis-like protein, and an ASR4-like protein, were required for Cf-4/Avr4-dependent HCD. Furthermore, the former four genes were essential for Cf-9/Avr9-dependent HCD; NbPip1, NbAsn, and NbMir, but not Nbf4, affected a nonadaptive bacterial pathogen Xanthomonas oryzae pv. oryzae-induced HCD in Nicotiana benthamiana. These data demonstrate that Pip1 and LeMir may play a general role in HCD and plant immunity and that the application of combined proteomic and RNA interfering analyses is an efficient strategy to identify genes required for HCD, disease resistance, and probably other biological processes in plants.