Department of Intelligent Systems Engineering, Indiana University, Bloomington, IN, USA.
Department of Chemical, Paper and Biomedical Engineering, Miami University, Oxford, OH, USA.
Sci Rep. 2021 Jan 18;11(1):1710. doi: 10.1038/s41598-020-78780-7.
Colorectal cancer and other cancers often metastasize to the liver in later stages of the disease, contributing significantly to patient death. While the biomechanical properties of the liver parenchyma (normal liver tissue) are known to affect tumor cell behavior in primary and metastatic tumors, the role of these properties in driving or inhibiting metastatic inception remains poorly understood, as are the longer-term multicellular dynamics. This study adopts a multi-model approach to study the dynamics of tumor-parenchyma biomechanical interactions during metastatic seeding and growth. We employ a detailed poroviscoelastic model of a liver lobule to study how micrometastases disrupt flow and pressure on short time scales. Results from short-time simulations in detailed single hepatic lobules motivate constitutive relations and biological hypotheses for a minimal agent-based model of metastatic growth in centimeter-scale tissue over months-long time scales. After a parameter space investigation, we find that the balance of basic tumor-parenchyma biomechanical interactions on shorter time scales (adhesion, repulsion, and elastic tissue deformation over minutes) and longer time scales (plastic tissue relaxation over hours) can explain a broad range of behaviors of micrometastases, without the need for complex molecular-scale signaling. These interactions may arrest the growth of micrometastases in a dormant state and prevent newly arriving cancer cells from establishing successful metastatic foci. Moreover, the simulations indicate ways in which dormant tumors could "reawaken" after changes in parenchymal tissue mechanical properties, as may arise during aging or following acute liver illness or injury. We conclude that the proposed modeling approach yields insight into the role of tumor-parenchyma biomechanics in promoting liver metastatic growth, and advances the longer term goal of identifying conditions to clinically arrest and reverse the course of late-stage cancer.
结直肠癌和其他癌症在疾病晚期常转移到肝脏,这是导致患者死亡的主要原因。虽然肝实质(正常肝组织)的生物力学特性已知会影响原发性和转移性肿瘤中的肿瘤细胞行为,但这些特性在驱动或抑制转移起始中的作用仍知之甚少,长期的多细胞动力学也是如此。本研究采用多模型方法研究转移性播种和生长过程中肿瘤-实质生物力学相互作用的动力学。我们采用肝小叶的详细粘弹性模型来研究微转移如何在短时间尺度上破坏流动和压力。详细单个肝小叶的短期模拟结果为转移性生长的最小基于代理的模型提供了本构关系和生物学假设,该模型适用于厘米级组织中的数月时间尺度。经过参数空间研究后,我们发现,在较短时间尺度(粘附、排斥和数分钟内的弹性组织变形)和较长时间尺度(数小时内的塑性组织松弛)上基本的肿瘤-实质生物力学相互作用的平衡可以解释微转移的广泛行为,而无需复杂的分子尺度信号。这些相互作用可以使微转移处于休眠状态而停止生长,并防止新到达的癌细胞建立成功的转移灶。此外,模拟表明,在实质组织力学特性发生变化(如衰老、急性肝疾病或损伤期间)时,休眠肿瘤可能会“重新觉醒”。我们得出结论,所提出的建模方法深入了解了肿瘤-实质生物力学在促进肝转移生长中的作用,并推进了识别条件以临床阻止和逆转晚期癌症进程的长期目标。