鼻咽癌血清比较蛋白质组学研究

目的 采用双向电泳-质谱技术优化肿瘤抗原筛选方法,筛选鼻咽癌肿瘤抗原.方法 鼻咽癌转移组、鼻咽癌未转移组和正常对照组血清先采用高丰度蛋白去除、脱盐预处理等以优化双向电泳,图像分析3组血清图谱寻找差异蛋白质点,基质辅助激光解吸电离飞行时间质谱对差异蛋白质点进行鉴定.结果 通过调整、优化各个阶段的实验条件,实验结果比较稳定,重复性也比较好,分辨率得到一定的提高.图谱比较所得29个差异蛋白质点,成功鉴定了23种蛋白质.与正常组比较,转铁蛋白、锌指蛋白544、甲状腺激素结合蛋白、NM23-H1蛋白和FAD合成酶在两组鼻咽癌患者中低表达,12-脂氧合酶、血清淀粉样蛋白A1前体、细胞色素P450、sICAM-1、组织蛋白酶G和组蛋白赖氨酸特异性脱甲基酶1等在两组鼻咽癌中均高表达.其中12-脂氧合酶、sICAM-1、组织蛋白酶G和组蛋白赖氨酸特异性脱甲基酶1在鼻咽癌转移组中比未转移组中表达增高,而热休克蛋白70则只在鼻咽癌转移组表达.结论 双向电泳-质谱技术可发现鼻咽癌发生发展过程中血清蛋白表达谱质或量的变化,从而为鼻咽癌的早期诊断和治疗奠定基础.     

LSD1 inhibitors: a patent review (2010-2015)

Introduction: Lysine demethylase 1 (LSD1) plays an important role in mediating the expression of genes involved in cancer and non-cancer diseases such as viral infections, cardiovascular and neurodegenerative disorders. It is involved in a number of processes from adipogenesis to cell adhesion to viral latency, regulating several cell pathways related with proliferation, development, and cell cycle control. Numerous chemical entities have been studied in recent years and some of them entered the clinical arena.

Areas covered: This review summarizes recent efforts in the drug development of LSD1 inhibitors reported in the patent literature covering the 2010-2015 period, including their potential use as therapeutics in cancerous, neurological, inflammatory, cardiovascular, and viral diseases.

Expert opinion: The development of novel potent and selective LSD1 inhibitors is ongoing, in order to improve their potency and selectivity against specific types of cancer or non-cancer diseases. More in-depth studies are required to assess the role of LSD1 inhibitors in the expression of LSD1 target genes, for a better assessment of the biochemistry underlying their efficacy, and to provide evidence for any possible side effects. Furthermore, an interesting therapeutic approach is the use of LSD1 inhibitors in conjunction with other epidrugs to combine their therapeutic potential, leading to innovative, personalized treatments.     

Nitrite binding to cytochrome P-450 from liver microsomes of trout (Salmo gairdneri Rich.) and effects on two microsomal enzymes

Addition of nitrite to dithionite-reduced trout liver microsomes leads to the conversion of cytochrome P-450 into a cytochrome P-420-NO complex, as it does in mammalian microsomes. A loss in cytochrome P-450 and an inhibition of aminopyrine demethylase (AP) activity were observed in vitro at nitrite-concentrations found in the liver of trout exposed in vivo to this toxin. Nitrite had no effect on dimethylaniline monooxygenase (DMA), a cytochrome P-450-independent enzyme.     

LSD1和EZH2蛋白表达与食管鳞癌术后预后相关性分析

目的 表现遗传学是当前肿瘤生物学研究的热点,本研究探讨食管鳞状细胞癌癌组织中组蛋白赖氨酸特异性脱甲基酶1 (lysine specific demethylase 1,LSD1)和Zeste基因增强子(enhancer of zeste homolog 2,EZH2)的蛋白表达与术后预后的相关性.方法 收集2008-05-07-2009-8-20在安阳市肿瘤医院胸外科行食管癌根治术的食管鳞癌患者85例.选取食管鳞癌组织85例,淋巴结转移癌组织30例,癌旁组织30例.免疫组织化学法检测食管鳞癌组织、淋巴结转移癌组织、癌旁组织中LSD1和EZH2蛋白表达.采用x2检验分析LSD1和EZH2蛋白表达与临床病理特征的关系;Spearman法分析LSD1和EZH2两者的相关性;Kaplan-meier法和Logrank-test检验分析LSD1和EZH2蛋白表达与术后总生存期(overall survival,OS)和无进展生存期(progression free survival,PFS)的关系,Cox模型多因素预后分析.结果 LSD1在食管鳞癌组织和淋巴结转移癌组织中的高表达率分别为64.7％ (55/85)和70.0％(21/30);癌旁组织均为少量阳性表达(低表达),主要位于增殖较旺盛的鳞状上皮基底部;LSD1在食管鳞癌组织、淋巴结转移癌组织的表达均高于癌旁组织(P＜0.001,P=0.001),食管鳞癌组织与淋巴结转移癌组织中的表达差异无统计学意义,P=0.598.EZH2在食管鳞癌组织、淋巴结转移癌组织和癌旁组织中的高表达率分别为62.3％(53/85)、76.7％ (23/30)和20.0％ (6/30);EZH2在食管鳞癌组织、淋巴结转移癌组织的表达均高于癌旁组织(P＜0.001,P=0.001),食管鳞癌组织与淋巴结转移癌组织中的表达差异无统计学意义,P=0.155.Spearman相关分析显示,LSD1和EZH2蛋白表达存在正相关,r=0.239,P=0.028.LSD1蛋白表达水平与pT分期(P=0.007)和分化程度(P=0.021)相关.EZH2蛋白表达水平与pT分期(P=0.022)、pN分期(P=0.046)和分化程度(P=0.018)相关.单因素分析显示,LSD1高表达患者的mOS和mPFS均低于低表达患者,均P＜0.001.EZH2高表达患者的mOS和mPFS均低于低表达患者,均P＜0.001.亚组分析LSD1和EZH2同时高表达患者的中位总生存期(median overall survival,mOS)和中位无进展生存期(median progress free survival,mPFS)均低于非LSD1和EZH2同时高表达患者,均P＜0.001.多因素分析显示,LSD1表达为独立的PFS预后指标,P=0.005;EZH2表达为独立的OS和PFS预后因素(P=0.003,0.014).结论 LSD1和EZH2在食管鳞癌组织和淋巴结转移癌组织中表达上调,高表达的患者与术后不良预后有关.     

Comparison of the expression levels of lysine-specific demethylase 1 and survival outcomes between triple-negative and non-triple-negative breast cancer

Lysine-specific demethylase 1 (LSD1) is a nuclear protein and the first histone demethylase to be identified. LSD1 is an evolutionarily conserved member of the FAD-dependent amine oxidase family and serves an important role in controlling gene expression. LSD1 has been implicated in the tumorigenesis and progression of several types of human cancer; however, to the best of our knowledge, the expression levels and clinical significance of LSD1 in triple-negative breast cancer (TNBC) and non-triple-negative breast cancer (NTNBC) have not been investigated in detail. Therefore, the present study aimed to compare the expression levels of LSD1 in TNBC and NTNBC to determine the prognostic significance of LSD1 in breast cancer. Previous studies have suggested that LSD1 may be involved in the carcinogenesis and progression of breast cancer; however, the findings of the present study indicated that LSD1 may not be a suitable molecular treatment target and auxiliary diagnostic indicator for TNBC and NTNBC.     

Anti-Proliferative Effect of Potential LSD1/CoREST Inhibitors Based on Molecular Dynamics Model for Treatment of SH-SY5Y Neuroblastoma Cancer Cell Line

Background: Lysine-specific demethylase is a demethylase enzyme that can remove methyl groups from histones H3K4me1/2 and H3K9me1/2. It is expressed in many cancers, where it impedes differentiation and contributes to cancer cell proliferation, cell metastasis and invasiveness, and is associated with inferior prognosis. LSD1 is associated with its corepressor protein CoREST, and utilizes tetrahydrofolate as a cofactor to accept CH2 from the demethylation process. The fact that the cofactor is best bound to the active site inspired us to explore its interactions to LSD1/CoREST enzyme complex utilizing molecular dynamics simulation, which aids designing novel and potent inhibitors. Objective: In this study we minted to identify a new potential LSD1/CoREST inhibitors and test the potency and the safety of such inhibitors against human neuroblastoma and fibroblast cells lines. Methods: We have implemented a previously derived model from the molecular dynamics simulation study and the key contacts to the active site in a subsequent structure based drug design and in-silico screening, which revealed a number of potential inhibitors toward LSD1/CoREST complex. The anti-proliferative activities of the identified compounds will be tested against neuroblastoma SH-SY5Y cancer cell line which known to highly express LSD1/CoREST complex. Results: In-silico mining on National Cancer Institute (NCI) database identified 55 promising and structurally diverse inhibitors. Applying the abovementioned molecular modeling procedure yielded four compounds of LSD1/CoREST inhibiters with IC50 < 2µM. The four lead compounds were tested against SH-SY5Y neuroblastoma cell line that known to express high level of LSD1 and illustrated a potent activity with an IC50 ranging from 0.195 to 1.52µM. To estimate the toxicity of the selective leads, they were tested against normal fibroblast cells and scored a relatively high IC50 ranging from 0.303 to ≥ 100µM. Conclusion: Our model revealed promising inhibitors that can be used in treating cancers that overexpress the LSD1 enzyme such as the SH-SY5Y neuroblastoma.     

LSD1及其在肿瘤发生中的调节作用

赖氨酸特异性组蛋白去甲基化酶(LSD1)是一种黄素腺嘌呤二核苷酸依赖性单胺氧化酶,可以特异性地催化单甲基化和二甲基化的组蛋白H3第4位赖氨酸(H3K4me1、H3K4me2)及第9位赖氨酸(H3K9me1、H3K9me2)去甲基化,从而调节基因的转录活性。近年来功能研究发现LSD1通过调节靶基因的表达,在肿瘤的发生、胚胎分化、异染色质的形成以及诱导多能干细胞形成等多方面起到重要作用。现对LSD1的结构、作用方式以及与肿瘤发生的关系等方面进行综述。     

组蛋白去甲基化酶JMJD1A及其生物学功能研究进展

组蛋白去甲基化酶JMJD1A（Jumonji do—main containing 1A）通过羟基化作用使组蛋白赖氨酸去甲基而参与转录调节,参与精子生成、能量代谢、干细胞调控,与肿瘤的发生和发展相关,是潜在的抗肿瘤药物的作用靶点。本文就JMJDlA的结构、催化反应机理、底物特异性、生物学功能和抑制剂作一综述。     

LSD1 inhibition: a therapeutic strategy in cancer?

Introduction: The role of epigenetic dysfunction in cancer is increasingly appreciated. This has raised the question as to whether enzymes that regulate the structure and function of chromatin might represent novel therapeutic targets. The histone demethylase LSD1 is one such candidate and novel, potent inhibitors are under development.

Areas covered: The literature on LSD1 (also known as KDM1A, AOF2, BHC110 or KIAA0601) was identified in Pubmed and is herein discussed. Areas covered include the structure and enzymatic activity of LSD1, its role in chromatin regulatory complexes, its functional roles in normal and malignant tissue, pharmacological inhibitors of its activity and their putative therapeutic roles.

Expert opinion: Pre-clinical data supporting a therapeutic role for LSD1 inhibitors are most encouraging in acute myeloid leukaemia, although optimal dosing strategies and beneficial combinations with other agents remain unclear. Studies making use of potent, selective LSD1 inhibitors active in the nanomolar range are required to establish therapeutic indications in other subtypes of haematological malignancy, and in solid tumours.