Wang Zhihui, Birch Christina M, Deisboeck Thomas S
Harvard-MIT (HST) Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA 02129, USA.
Biosystems. 2008 Jun;92(3):249-58. doi: 10.1016/j.biosystems.2008.03.002. Epub 2008 Mar 21.
Sensitivity analysis is an effective tool for systematically identifying specific perturbations in parameters that have significant effects on the behavior of a given biosystem, at the scale investigated. In this work, using a two-dimensional, multiscale non-small cell lung cancer (NSCLC) model, we examine the effects of perturbations in system parameters which span both molecular and cellular levels, i.e. across scales of interest. This is achieved by first linking molecular and cellular activities and then assessing the influence of parameters at the molecular level on the tumor's spatio-temporal expansion rate, which serves as the output behavior at the cellular level. Overall, the algorithm operated reliably over relatively large variations of most parameters, hence confirming the robustness of the model. However, three pathway components (proteins PKC, MEK, and ERK) and eleven reaction steps were determined to be of critical importance by employing a sensitivity coefficient as an evaluation index. Each of these sensitive parameters exhibited a similar changing pattern in that a relatively larger increase or decrease in its value resulted in a lesser influence on the system's cellular performance. This study provides a novel cross-scaled approach to analyzing sensitivities of computational model parameters and proposes its application to interdisciplinary biomarker studies.
敏感性分析是一种有效的工具,用于在研究尺度上系统地识别对给定生物系统行为有显著影响的参数中的特定扰动。在这项工作中,我们使用二维多尺度非小细胞肺癌(NSCLC)模型,研究跨越分子和细胞水平(即跨感兴趣尺度)的系统参数扰动的影响。这首先通过将分子和细胞活动联系起来,然后评估分子水平参数对肿瘤时空扩展速率的影响来实现,肿瘤时空扩展速率作为细胞水平的输出行为。总体而言,该算法在大多数参数的相对较大变化范围内可靠运行,从而证实了模型的稳健性。然而,通过使用敏感性系数作为评估指标,确定了三个信号通路成分(蛋白PKC、MEK和ERK)和十一个反应步骤至关重要。这些敏感参数中的每一个都表现出相似的变化模式,即其值相对较大的增加或减少对系统的细胞性能影响较小。本研究提供了一种新颖的跨尺度方法来分析计算模型参数的敏感性,并提出了其在跨学科生物标志物研究中的应用。