Intratumor heterogeneity is a key hallmark of cancer that contributes to progression and therapeutic resistance. Phenotypic heterogeneity is in part caused by Darwinian selection of subclones that arise by random (epi)genetic aberrations. In addition, cancer cells are endowed with increased cellular plasticity compared with their normal counterparts, further adding to their heterogeneous behavior. However, the molecular mechanisms underpinning cancer cell plasticity are incompletely understood. Here, I outline the hypothesis that cancer-associated perturbations collectively disrupt normal gene regulatory networks (GRNs) by increasing their entropy. Importantly, in this model both somatic driver and passenger alterations contribute to ‘perturbation-driven entropy’, thereby increasing phenotypic heterogeneity and evolvability. This additional layer of heterogeneity may contribute to our understanding of cancer evolution and therapeutic resistance.

肿瘤内异质性是癌症的关键标志，有助于进展和治疗抵抗力。表型异质性部分是由于随机（表观）遗传畸变引起的达尔文亚克隆选择所致。此外，与正常癌细胞相比，癌细胞具有更高的细胞可塑性，从而进一步增强了它们的异质性。但是，尚不完全了解支持癌细胞可塑性的分子机制。在这里，我概述了一个假设，即与癌症相关的扰动会通过增加其熵来共同破坏正常的基因调节网络（GRN）。重要的是，在该模型中，躯体驾驶员和乘客的改变都对“摄动驱动的熵”做出了贡献，从而增加了表型异质性和可进化性。