Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan.
Department of Neurosurgery, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan.
Sci Rep. 2021 May 27;11(1):11223. doi: 10.1038/s41598-021-90841-z.
Amide proton transfer (APT) imaging is a magnetic resonance (MR) molecular imaging technique that is sensitive to mobile proteins and peptides in living tissue. Studies have shown that APT-related signal intensity (APTSI) parallels with the malignancy grade of gliomas, allowing the preoperative assessment of tumor grades. An increased APTSI in malignant gliomas has been attributed to cytosolic proteins and peptides in proliferating tumor cells; however, the exact underlying mechanism is poorly understood. To get an insight into the mechanism of high APTSI in malignant gliomas, we investigated the correlations between APTSI and several MR imaging parameters including apparent diffusion coefficient (ADC), relative cerebral blood volume and pharmacokinetic parameters obtained in the same regions-of-interest in 22 high-grade gliomas. We found a significant positive correlation between APTSI and ADC (ρ = 0.625 and 0.490 for observers 1 and 2, respectively; p < 0.001 for both), which is known to be inversely correlated with cell density. Multiple regression analysis revealed that ADC was significantly associated with APTSI (p < 0.001 for both observers). Our results suggest possible roles of extracellular proteins and peptides in high APTSI in malignant gliomas.
酰胺质子转移（APT）成像是一种磁共振（MR）分子成像技术，对活组织中移动的蛋白质和肽敏感。研究表明，APT 相关的信号强度（APTSI）与神经胶质瘤的恶性程度平行，允许术前评估肿瘤的分级。恶性神经胶质瘤中增加的 APTSI归因于增殖肿瘤细胞中的细胞质蛋白质和肽；然而，其确切的潜在机制尚未完全了解。为了深入了解恶性神经胶质瘤中高 APTSI 的机制，我们研究了 APTSI 与包括表观扩散系数（ADC）在内的几种磁共振成像参数之间的相关性，以及在 22 例高级别神经胶质瘤的相同感兴趣区域中获得的相对脑血容量和药代动力学参数。我们发现 APTSI 与 ADC 之间存在显著的正相关（观察者 1 和 2 的 ρ 值分别为 0.625 和 0.490；均 p < 0.001），这与细胞密度呈负相关。多元回归分析显示，ADC 与 APTSI 显著相关（观察者 1 和 2 的 p 值均 < 0.001）。我们的结果表明，细胞外蛋白质和肽可能在恶性神经胶质瘤中的高 APTSI 中发挥作用。
