Nofiele Joris Tchouala, Czarnota Gregory J, Cheng Hai-Ling Margaret
Mol Imaging. 2014;13. doi: 10.2310/7290.2013.00071.
Cancer cells with a high metastatic potential will more likely escape and form distant tumors. Once the cancer has spread, a cure is rarely possible. Unfortunately, metastasis often proceeds unnoticed until a secondary tumor has formed. The culprit is that current imaging-based cancer screening and diagnosis are limited to assessing gross physical changes, not the earliest cellular changes that drive cancer progression. The purpose of this study is to develop a novel noninvasive magnetic resonance (MR) cellular imaging capability for characterizing the metastatic potential of breast cancer and enable early cancer detection. This MR method relies on imaging cell uptake of manganese, an endogenous calcium analogue and an MR contrast agent, to detect aggressive cancer cells. Studies on normal breast epithelial cells and three breast cancer cell lines, from nonmetastatic to highly metastatic, demonstrated that aggressive cancer cells appeared significantly brighter on MR as a result of altered cell uptake of manganese. In vivo results in nude rats showed that aggressive tumors that are otherwise unseen on conventional gadolinium-enhanced MR imaging are detected after manganese injection. This cellular MR imaging technology brings a critically needed, unique dimension to cancer imaging by enabling us to identify and characterize metastatic cancer cells at their earliest appearance.
具有高转移潜能的癌细胞更有可能逃脱并形成远处肿瘤。一旦癌症发生转移，治愈的可能性就很小了。不幸的是，转移通常在不知不觉中发生，直到形成继发性肿瘤才被发现。原因在于，目前基于成像的癌症筛查和诊断仅限于评估大体形态变化，而无法检测到驱动癌症进展的最早细胞变化。本研究的目的是开发一种新型的无创磁共振（MR）细胞成像技术，用于表征乳腺癌的转移潜能并实现癌症的早期检测。这种MR方法依靠对锰（一种内源性钙类似物和MR造影剂）的细胞摄取成像，来检测侵袭性癌细胞。对正常乳腺上皮细胞和三种从非转移性到高转移性的乳腺癌细胞系进行的研究表明，由于锰的细胞摄取改变，侵袭性癌细胞在MR图像上显得明显更亮。在裸鼠体内的结果显示，在注射锰后，可以检测到在传统钆增强MR成像上原本无法看到的侵袭性肿瘤。这种细胞MR成像技术为癌症成像带来了迫切需要的独特维度，使我们能够在转移性癌细胞最早出现时对其进行识别和表征。
