STRESS-RELATED CHANGES IN GENE EXPRESSION AS BIOMARKERS OF RELAPSE VULNERABILITY

描述(申请人提供)：这项拟议的研究将持续两年，将评估基因表达的变化与压力诱导的渴望、负面情绪和生理学指标之间的关系，这些指标以前被证明可以预测治疗后早期复发的风险。该项目的长期目标是开发新的分子工具，可以用来预测和监测对酒精依赖的特定治疗的反应。我们小组进行的初步研究发现，酒精依赖者和社交饮酒者的外周血液基因表达存在差异。与这些基因相关的生物过程包括细胞凋亡(细胞程序性死亡)、细胞周期调节和细胞内信号级联反应。这些基因表达差异涉及的关键转录因子包括HNF4-α、c-myc、ESR1、AR和NF-：B。涉及这些转录因子的基因网络的异常表达可能是酒精依赖者对应激反应增强的基础，以及治疗反应、复发风险和共病疾病(如抑郁症)的差异。在拟议的研究中，我们将招募(n=25)寻求治疗的酒精依赖受试者和(n=25)社交饮酒者，并从先前描述的涉及个性化压力或中性放松情景(每次会话一种想象条件)的简短引导成像会议之前、之后和一小时后收集的血液中分离RNA(Sinha等人，2008年)。在长时间(28天)禁食后，将进行成像治疗。基因表达水平将通过使用Illumina Sentrix BeadChip(Human-6v2)阵列(与我们初步研究中使用的相同平台)的微阵列杂交来评估。选择感兴趣的基因的差异表达将使用实时定量逆转录聚合酶链式反应(qRT-PCR)来确认。酒精渴望、焦虑和情绪评级、行为痛苦反应、心率、血压和唾液皮质醇测量将在每一次会议期间进行评估。在实验室课程结束后，还将对酗酒者进行90天的跟踪调查，以评估酗酒情况。具体目标包括：(1)评估压力想象与中性放松想象相比是否会导致外周血液基因表达的不同变化；(2)评估酒精依赖者和健康对照组在通过诱导特定的压力相关基因来衡量他们对压力想象的反应方面是否存在差异；以及(3)确定与压力相关的基因表达变化与先前被证明预测复发风险的生理和情感反应之间的关系。作为一项探索性目标，我们还将评估特定目标1-3中确定的与压力相关的基因表达变化与酒精依赖受试者在测试后90天内复发风险之间的关系。 公共卫生相关性：众所周知，压力是酒精依赖复发的危险因素。该项目的目标是确定特定的压力相关基因，这些基因可能预测酒精依赖受试者的复发风险，并允许高风险个体被指导进行更密集的治疗干预。更好地了解压力对复发风险的影响的分子和遗传途径，也将有助于开发更有效的酒精和其他滥用药物依赖的治疗方法。

DESCRIPTION (provided by applicant): The proposed study, which will be of 2 years duration, will assess the relationship between changes in gene-expression and laboratory measures of stress-induced craving, negative emotion, and physiology previously shown to predict risk for early relapse after treatment. The long-term goal of this project is to develop novel molecular tools that can be used to predict and monitor the response to specific treatments for alcohol dependence. Preliminary studies conducted by our group have identified peripheral blood gene-expression differences between alcohol dependent subjects and social drinkers. Biological processes associated with these genes include apoptosis (programmed cell death), cell cycle regulation, and intracellular signaling cascades. Key transcription factors implicated by these gene- expression differences include HNF4-alpha, c-myc, ESR1, AR, and NF-:B. Abnormal expression of gene- networks involving these transcription factors may underlie the heightened response to stress observed in alcohol dependent subjects as well as differences in response to treatment, risk for relapse, and co-morbid disorders (e.g. depression). In the proposed study, we will recruit (n=25) treatment-seeking alcohol-dependent subjects, and (n=25) social drinkers and isolate RNA from blood collected before, immediately after, and one hour after brief guided imagery sessions involving personalized stressful or neutral-relaxing situations (one imagery condition per session) as previously described (Sinha et al., 2008). Imagery sessions will be conducted after a period of prolonged (28-day) abstinence. Gene-expression levels will be assed by microarray hybridization using Illumina Sentrix Beadchip (Human-6v2) arrays (the same platform used in our preliminary studies). Differential expression of selected genes of interested will be confirmed using Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Alcohol craving, anxiety and emotion ratings, behavioral distress responses, heart rate, blood pressure, and salivary cortisol measures will be assessed during each session. Alcoholic subjects will also be followed for 90 days after completion of the laboratory sessions to assess alcohol relapse. Specific aims include: (1) assessing whether stress imagery as compared to neutral-relaxing imagery results in differential changes in peripheral blood gene-expression; (2) assessing whether alcohol-dependent subjects and healthy controls differ in their reactivity to stress imagery as measured by induction of specific stress-related genes; and (3) determining the relationship between stress-related changes in gene-expression and physiologic and emotional responses previously shown to predict risk for relapse. As an exploratory aim we will also assess the relationship between stress-related changes in gene-expression identified in specific aims 1-3 and risk for relapse among alcohol-dependent subjects during the 90 days after testing. PUBLIC HEALTH RELEVANCE: Stress is a well known risk factor for relapse in alcohol-dependence. The goal of this project is to identify specific stress-related genes that may predict the risk for relapse in alcohol dependent subjects and allow individuals at higher-risk to be directed to more intensive treatment interventions. Better understanding of the molecular and genetic pathways mediating the effects of stress on the risk for relapse will also aid in the development of more effective treatments for dependence on alcohol and other drugs of abuse.