Department of Bioengineering and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Department of Electrical and Computer Engineering and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Anal Chem. 2023 Feb 14;95(6):3349-3357. doi: 10.1021/acs.analchem.2c04554. Epub 2022 Dec 27.
Cell cycle progression plays a vital role in regulating proliferation, metabolism, and apoptosis. Three-dimensional (3D) cell cultures have emerged as an important class of disease models, and incorporating the variation occurring from cell cycle progression in these systems is critical. Here, we report the use of Fourier transform infrared (FT-IR) spectroscopic imaging to identify subtle biochemical changes within cells, indicative of the G1/S and G2/M phases of the cell cycle. Following previous studies, we first synchronized samples from two-dimensional (2D) cell cultures, confirmed their states by flow cytometry and DNA quantification, and recorded spectra. We determined two critical wavenumbers (1059 and 1219 cm) as spectral indicators of the cell cycle for a set of isogenic breast cancer cell lines (MCF10AT series). These two simple spectral markers were then applied to distinguish cell cycle stages in a 3D cell culture model using four cell lines that represent the main stages of cancer progression from normal cells to metastatic disease. Temporal dependence of spectral biomarkers during acini maturation validated the hypothesis that the cells are more proliferative in the early stages of acini development; later stages of the culture showed stability in the overall composition but unique spatial differences in cells in the two phases. Altogether, this study presents a computational and quantitative approach for cell phase analysis in tissue-like 3D structures without any biomarker staining and provides a means to characterize the impact of the cell cycle on 3D biological systems and disease diagnostic studies using IR imaging.
细胞周期进程在调节增殖、代谢和凋亡方面起着至关重要的作用。三维（3D）细胞培养已成为一类重要的疾病模型，在这些系统中纳入细胞周期进程中的变化至关重要。在这里，我们报告使用傅里叶变换红外（FT-IR）光谱成像来识别细胞内微妙的生化变化，这些变化表明细胞周期处于 G1/S 和 G2/M 期。在之前的研究之后，我们首先对来自二维（2D）细胞培养物的样品进行同步，通过流式细胞术和 DNA 定量来确认其状态，并记录光谱。我们确定了两个关键的波数（1059 和 1219 cm）作为一组同源乳腺癌细胞系（MCF10AT 系列）细胞周期的光谱指标。然后，将这两个简单的光谱标记物应用于使用代表从正常细胞到转移性疾病的癌症进展主要阶段的四种细胞系的 3D 细胞培养模型中，以区分细胞周期阶段。在腺泡成熟过程中光谱生物标志物的时间依赖性验证了这样一种假设，即细胞在腺泡发育的早期阶段更具增殖性；培养的后期阶段在整体组成上表现出稳定性，但在两个阶段的细胞中存在独特的空间差异。总的来说，这项研究提出了一种在无任何生物标志物染色的情况下对组织样 3D 结构中的细胞相进行分析的计算和定量方法，并提供了一种使用 IR 成像对 3D 生物系统和疾病诊断研究中细胞周期的影响进行特征描述的手段。
