RESUMO
BACKGROUND: t(8;21)(q22;q22) is one of the most frequent chromosomal abnormalities in acute myeloid leukemia (AML), leading to the generation of the fusion protein AML1-ETO. Despite t(8;21) AML being considered as a subtype with a favorable prognosis, approximately 30-50% of patients experience drug resistance and subsequent relapse. N6-methyladenosine (m6A) is demonstrated to be involved in the development of AML. However, the regulatory mechanisms between AML1-ETO and m6A-related enzymes and the roles of dysregulated m6A modifications in the t(8;21)-leukemogenesis and chemoresistance remain elusive. METHODS: Chromatin immunoprecipitation, dual-luciferase reporter assay, m6A-qPCR, RNA immunoprecipitation, and RNA stability assay were used to investigate a regulatory loop between AML1-ETO and FTO, an m6A demethylase. Gain- and loss-of-function experiments both in vitro and in vivo were further performed. Transcriptome-wide RNA sequencing and m6A sequencing were conducted to identify the potential targets of FTO. RESULTS: Here we show that FTO is highly expressed in t(8;21) AML, especially in patients with primary refractory disease. The expression of FTO is positively correlated with AML1-ETO, which is attributed to a positive regulatory loop between the AML1-ETO and FTO. Mechanistically, AML1-ETO upregulates FTO expression through inhibiting the transcriptional repression of FTO mediated by PU.1. Meanwhile, FTO promotes the expression of AML1-ETO by inhibiting YTHDF2-mediated AML1-ETO mRNA decay. Inactivation of FTO significantly suppresses cell proliferation, promotes cell differentiation and renders resistant t(8;21) AML cells sensitive to Ara-C. FTO exerts functions by regulating its mRNA targets, especially IGFBP2, in an m6A-dependent manner. Regain of Ara-C tolerance is observed when IGFBP2 is overexpressed in FTO-knockdown t(8;21) AML cells. CONCLUSION: Our work reveals a therapeutic potential of targeting AML1-ETO/FTO/IGFBP2 minicircuitry in the treatment for t(8;21) patients with resistance to Ara-C.
RESUMO
Natural tocopherols have strong antioxidant and physiological functions, which are mainly produced from vegetable oil deodorized distillates. In this work, a simple and green solvent extraction method based on deep eutectic solvent has been developed to simultaneously extract three isomers of tocopherols (α, γ and δ-tocopherols) from soybean oil deodorizer distillate (SODD). The key factor to affect the solvent extraction efficiency was proposed that phenolic deep eutectic solvents interacted with targeted tocopherols mainly through π-π bonds interaction. This sustainable extraction process included two steps. Firstly, total tocopherols were extracted from SODD at room temperature by phenolic deep eutectic solvent composed of ChCl and p-cresol. Subsequently, tocopherols were successfully separated from deep eutectic solvent phase by re-extraction with n-hexane, and tocopherols products could be simply recovered. Under the optimum extraction conditions, the extraction efficiency of total tocopherols (α, γ and δ-tocopherols) from SODD was 77.6% after extraction with phenolic deep eutectic solvent.
Assuntos
Colina/química , Cresóis/química , Óleo de Soja/química , Tocoferóis/isolamento & purificação , Conformação Molecular , Solventes/química , Temperatura , Tocoferóis/químicaRESUMO
BACKGROUND: Milk Thistle fruit is an important herb popularly consumed worldwide for a very long time. Silybin is the main bioactive constituent of the herb, and it has been approved by US Food and Drug Administration (FDA) as a medicine to treat liver diseases. Presently, using conventional technology, the meal of Milk Thistle fruit is used as the raw material to extract silybin. OBJECTIVE: To investigate the necessity of detaching husk from kernel of the herb and also to propose a novel approach to enhance the extraction technology in pharmaceutical practices. MATERIALS AND METHODS: The husk of Milk Thistle fruit was detached from the kernel of the herb using an automatic huller specially designed for this application. The husk and the meal of Milk Thistle fruit was subsequently refluxed, separately, with production rate of silybin as index for comparison of their extraction effect. RESULTS: The highest production rate was achieved under optimized condition. The husk was extracted 2 times (3 hrs each) using ethyl acetate, and the ratio of solvent to raw material was 8:1. The extract was allowed to be crystallized out. CONCLUSION: The separation of kernel from the husk of Milk Thistle fruit and using only the husk as raw material can largely enhance the extraction of silybin.