Department of Radiology, University of Cambridge, Cambridge, United Kingdom.
Department of Radiology, University of Cambridge, Cambridge, United Kingdom; Cancer Research UK Cambridge Center, Cambridge, United Kingdom.
Eur J Radiol. 2023 Oct;167:111058. doi: 10.1016/j.ejrad.2023.111058. Epub 2023 Aug 22.
Tumour metabolism can be imaged with a novel imaging technique termed hyperpolarised carbon-13 (C)-MRI using probes, i.e., endogenously found molecules that are labeled with C. Hyperpolarisation of the C label increases the sensitivity to a level that allows dynamic imaging of the distribution and metabolism of the probes. Dynamic imaging of [1-C]pyruvate metabolism is of particular biological interest in cancer because of the Warburg effect resulting in the intratumoural accumulation of [1-C]pyruvate and conversion to [1-C]lactate. Numerous preclinical studies in breast cancer and other tumours have shown that hyperpolarised C-pyruvate has potential for metabolic phenotyping and response assessment at earlier timepoints than the current clinical imaging techniques allow. The clinical feasibility of hyperpolarised C-MRI after the injection of pyruvate in patients with breast cancer has now been demonstrated, with increased C-label exchange between pyruvate and lactate present in higher grade tumours with associated increased expression of the monocarboxylate transporter 1 (MCT1), the transmembrane transporter mediating intracellular pyruvate uptake, and lactate dehydrogenase (LDH) as the enzyme catalysing the conversion of pyruvate to lactate. Furthermore, a study in patients with breast cancer undergoing neoadjuvant chemotherapy suggested that early changes in C-label exchange can distinguish between patients who reach pathologic complete response (pCR) and those who do not. This review summarises the current literature on preclinical and clinical research on hyperpolarised C-MRI with [1-C]-pyruvate in breast cancer imaging.
肿瘤代谢可以通过一种称为 13C 磁共振波谱成像（13C-MRS）的新型成像技术进行成像，该技术使用探针，即标记有 13C 的内源性发现的分子。13C 标记的极化增加了灵敏度，使探针的分布和代谢的动态成像成为可能。由于导致肿瘤内 13C-丙酮酸积聚和转化为 13C-乳酸的沃伯格效应，[1-C]丙酮酸代谢的动态成像在癌症中具有特殊的生物学意义。在乳腺癌和其他肿瘤的大量临床前研究表明，与当前的临床成像技术相比，极化 13C-丙酮酸具有在更早时间点进行代谢表型分析和反应评估的潜力。现已证明，在乳腺癌患者中注射丙酮酸后进行极化 13C-MRI 的临床可行性，在高等级肿瘤中存在更高的丙酮酸和乳酸之间的 13C 标记交换，与单羧酸转运蛋白 1（MCT1）的表达增加相关，MCT1 是介导细胞内丙酮酸摄取的跨膜转运蛋白，以及乳酸脱氢酶（LDH）作为催化丙酮酸转化为乳酸的酶。此外，一项对接受新辅助化疗的乳腺癌患者的研究表明，13C 标记交换的早期变化可以区分达到病理完全缓解（pCR）的患者和未达到 pCR 的患者。这篇综述总结了关于乳腺癌成像中使用 13C-丙酮酸的极化 13C-MRI 的临床前和临床研究的当前文献。
