Greater transiency in modulation of gene expression is the predominant difference between the actions of bryostatin 1 and phorbol ester in LNCaP and U937 cells [set 2]. Greater transiency in modulation of gene expression is the predominant difference between the actions of bryostatin 1 and phorbol ester in LNCaP and U937 cells [set 2]

Bryostatin 1, like the phorbol ester PMA, activates protein kinase C (PKC) in vitro but paradoxically blocks many phorbol ester responses in vivo. Results with a limited panel of genes suggested that transiency of action was an important mechanism contributing to this differential cellular response. Here, we examined global gene expression in LNCaP and U937 cell lines to probe the extent to which transiency of action captures the difference in response. While different genes showed different patterns of relative response, the overall pattern was reflective of an initial PMA-like response to bryostatin 1 followed by variable transiency of the continued response. This conclusion was further strengthened by detailed time course measurements by qPCR of selected genes. Merle 23, a bryostatin derivative with biological behavior intermediate between that of bryostatin 1 and PMA, was likewise intermediate for transiency of action. Both the LNCaP and U937 cell lines behaved similarly, but the extent of transiency in response to bryostatin 1 was greater in the LNCaP cells. Overall design: Forty seven samples were analyzed in the study; Univariate one-way analysis of variance with planned contrasts (Partek® Genomics Suite 6.5) was used to identify significant changes in gene expression due to bryostatin 1 and PMA 1-hour and 6-hour treatments in LNCaP and U937 cells. The ANOVA p-values were converted to false discovery adjusted q-values with the method of Storey [Storey 2002] implemented in the R package qvalue [R core team 2013, Dabney and Storey]. Gene co-expression network was built with the R package WGCNA (Langfelder and Horvath, 2012).

草苔虫素1（Bryostatin 1）与佛波酯（PMA）类似，可在体外激活蛋白激酶C（PKC），但却会在体内反常地阻断诸多佛波酯介导的应答反应。针对有限基因集的实验结果表明，作用的瞬时性是导致这种差异化细胞应答的重要机制之一。本研究通过检测LNCaP与U937细胞系的全基因表达谱，探究作用瞬时性能在多大程度上解释这种应答差异。尽管不同基因呈现出各异的相对应答模式，但整体模式反映出：草苔虫素1的应答最初呈现PMA类似的特征，后续持续应答的瞬时性则存在差异。针对选定基因的实时定量PCR（qPCR）详细时间进程检测结果进一步验证了这一结论。Merle 23作为草苔虫素1的衍生物，其生物学特性介于草苔虫素1与PMA之间，其作用瞬时性同样处于二者的中间水平。LNCaP与U937细胞系的表现相似，但LNCaP细胞中针对草苔虫素1的应答瞬时性程度更高。
研究设计：本研究共分析47份样本；采用带有预设对照的单变量单因素方差分析（通过Partek® Genomics Suite 6.5软件实现），以鉴定LNCaP与U937细胞经草苔虫素1或PMA处理1小时、6小时后基因表达的显著变化。本研究采用R包qvalue[R核心团队2013，Dabney与Storey]中实现的Storey方法[Storey 2002]，将方差分析得到的p值转换为错误发现率校正后的q值。采用R包WGCNA（Langfelder与Horvath，2012）构建基因共表达网络。