A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.
Department of Radiology, University of Turku, Turku, Finland.
NMR Biomed. 2021 Apr;34(4):e4483. doi: 10.1002/nbm.4483. Epub 2021 Feb 4.
MRI is a common method of prostate cancer diagnosis. Several MRI-derived markers, including the apparent diffusion coefficient (ADC) based on diffusion-weighted imaging, have been shown to provide values for prostate cancer detection and characterization. The hypothesis of the study was that docetaxel chemotherapy response could be picked up earlier with rotating frame relaxation times T and T than with the continuous wave T , adiabatic T , adiabatic T , T , T or water ADC. Human PC3 prostate cancer cells expressing a red fluorescent protein were implanted in 21 male mice. Docetaxel chemotherapy was given once a week starting 1 week after cell implantation for 10 randomly selected mice, while the rest served as a control group (n = 11). The MRI consisted of relaxation along a fictitious field (RAFF) in the second (RAFF2) and fourth (RAFF4) rotating frames, T and T , continuous wave T , adiabatic T and adiabatic T relaxation time measurements and water ADC. MRI was conducted at 7 T, once a week up to 4 weeks from cell implantation. The tumor volume was monitored using T -weighted MRI and optical imaging. The histology was evaluated after the last imaging time point. Significantly reduced RAFFn, T T and conventional relaxation times 4 weeks after tumor implantation were observed in the treated tumors compared with the controls. The clearest short- and long-term responses were obtained with T , while no clear improvement in response to treatment was detected with novel methods compared with conventional methods or with RAFFn compared with all others. The tumor volume decreased after a two-week time point for the treated group and increased significantly in the control group, which was supported by increasing red fluorescent light emission in the control tumors. Decreased relaxation times were associated with successful chemotherapy outcomes. The results indicate altered relaxation mechanisms compared with higher dose chemotherapies previously published.
MRI 是一种常见的前列腺癌诊断方法。几项基于磁共振扩散加权成像的 MRI 衍生标志物，包括表观扩散系数（ADC），已被证明可用于前列腺癌的检测和特征描述。本研究的假设是，与连续波 T 1 、绝热 T 1 、绝热 T 2 、T 2 、T 2 或水 ADC 相比，旋转框架弛豫时间 T 1 和 T 2 可以更早地检测到多西紫杉醇化疗的反应。表达红色荧光蛋白的人前列腺癌细胞 PC3 被植入 21 只雄性小鼠中。在细胞植入后 1 周开始，每周给 10 只随机选择的小鼠进行多西紫杉醇化疗，其余作为对照组（n = 11）。MRI 包括在第二个（RAFF2）和第四个（RAFF4）旋转框架中沿虚构场（RAFF）的弛豫、T 1 和 T 2 、连续波 T 1 、绝热 T 1 和绝热 T 2 弛豫时间测量以及水 ADC。在 7T 进行 MRI 检查，从细胞植入后每周一次，共进行 4 周。使用 T 1 加权 MRI 和光学成像监测肿瘤体积。在最后一次成像时间点后进行组织学评估。与对照组相比，治疗肿瘤在肿瘤植入后 4 周时，RAFFn、T 1 和常规弛豫时间明显降低。与传统方法或 RAFFn 相比，T 1 获得了最清晰的短期和长期反应，而与常规方法或 RAFFn 相比，新型方法并未检测到治疗反应的明显改善。治疗组的肿瘤体积在两周时间点后减小，对照组的肿瘤体积显著增加，这得到了对照组肿瘤中红色荧光发射增加的支持。弛豫时间的降低与化疗成功的结果相关。结果表明，与之前发表的高剂量化疗相比，松弛机制发生了改变。
