MI Lab, Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
NMR Biomed. 2013 May;26(5):600-6. doi: 10.1002/nbm.2901. Epub 2012 Dec 27.
MR metabolic profiling of the prostate is promising as an additional diagnostic approach to separate indolent from aggressive prostate cancer. The objective of this study was to assess the relationship between the Gleason score and the metabolic biomarker (choline + creatine + spermine)/citrate (CCS/C) measured by ex vivo high-resolution magic angle spinning MRS (HR-MAS MRS) and in vivo MRSI, and to evaluate the correlation between in vivo- and ex vivo-measured metabolite ratios from spatially matched prostate regions. Patients (n = 13) underwent in vivo MRSI prior to radical prostatectomy. A prostate tissue slice was snap-frozen shortly after surgery and the locations of tissue samples (n = 40) collected for ex vivo HR-MAS were matched to in vivo MRSI voxels (n = 40). In vivo MRSI was performed on a 3T clinical MR system and ex vivo HR-MAS on a 14.1T magnet. Relative metabolite concentrations were calculated by LCModel fitting of in vivo spectra and by peak integration of ex vivo spectra. Spearman's rank correlations (ρ) between CCS/C from in vivo and ex vivo MR spectra, and with their corresponding Gleason score, were calculated. There was a strong positive correlation between the Gleason score and CCS/C measured both in vivo and ex vivo (ρ = 0.77 and ρ = 0.69, respectively; p < 0.001), and between in vivo and ex vivo metabolite ratios from spatially matched regions (ρ = 0.67, p < 0.001). Our data indicate that MR metabolic profiling is a potentially useful tool for the assessment of cancer aggressiveness. Moreover, the good correlation between in vivo- and ex vivo-measured CCS/C demonstrates that our method is able to bridge MRSI and HR-MAS molecular analysis.
MR 前列腺代谢组学有望成为一种额外的诊断方法，用于区分惰性和侵袭性前列腺癌。本研究的目的是评估通过离体高分辨率磁共振波谱（HR-MAS MRS）和体内磁共振波谱成像（MRSI）测量的 Gleason 评分与代谢生物标志物（胆碱+肌酸+精胺）/柠檬酸盐（CCS/C）之间的关系，并评估来自空间匹配前列腺区域的体内和离体测量代谢物比值之间的相关性。患者（n = 13）在根治性前列腺切除术前接受了体内 MRSI。手术后不久，立即对前列腺组织切片进行冷冻，并对用于离体 HR-MAS 的组织样本（n = 40）的位置进行匹配，以匹配体内 MRSI 体素（n = 40）。体内 MRSI 在 3T 临床磁共振系统上进行，离体 HR-MAS 在 14.1T 磁体上进行。通过 LCModel 拟合体内光谱和离体光谱的峰积分计算相对代谢物浓度。计算了来自体内和离体 MR 光谱的 CCS/C 与 Gleason 评分之间的 Spearman 秩相关系数（ρ）。Gleason 评分与体内和离体测量的 CCS/C 之间呈强正相关（ρ分别为 0.77 和 0.69，p < 0.001），并且与空间匹配区域的体内和离体代谢物比值之间呈强正相关（ρ = 0.67，p < 0.001）。我们的数据表明，MR 代谢组学是评估癌症侵袭性的一种潜在有用工具。此外，体内和离体测量的 CCS/C 之间的良好相关性表明，我们的方法能够桥接 MRSI 和 HR-MAS 分子分析。
