Li Yu-Ling, Zhou Bo-Wen, Cao Yu-Qi, Zhang Jing, Zhang Li, Guo Yin-Long
State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
Anal Chem. 2021 Mar 16;93(10):4576-4583. doi: 10.1021/acs.analchem.0c05015. Epub 2021 Mar 3.
noncontact cell-based coculture models are frequently employed to study cell-to-cell communication. However, these models cannot accurately represent the complexity of signaling. d-Lactate is an unusual metabolite produced and released by cancer cells. The characterization of d-lactate is challenging as it shares the same mass but has much lower amounts compared with l-lactate. Herein, d-α-hydroxy acids were specifically recognized and dehydrogenated by d-α-hydroxy acid dehydrogenase. The dehydrogenation products were rapidly quaternized for enhancement of mass signals. An on-probe enzymatic dehydrogenation-derivatization method was proposed for chiral analysis of α-hydroxy acids at the single-cell level. It is a promising amplification methodology and affords over 3 orders of magnitude signal enhancement. Furthermore, direct contact coculture models were used to precisely mimic the tumor microenvironment and explore the communication between cancer and normal cells. Single-cell mass spectrometry (SCMS) was further applied to easily sample cell extracts and study the differences of the aspects of small molecule metabolism in cocultured cells. On the basis of direct contact coculture SCMS, several differential small molecule metabolites and differences of oxidative stress between cocultured and monocultured normal cells were successfully detected. Additionally, d-lactate was discovered as a valuable differential metabolite with application of the two developed methods. It may account for the cancer-associated metabolic behavior of normal cells. These changes could be relieved after d-lactate metabolism-related drug treatment. This discovery may promote the investigation of d-lactate metabolism, which may provide a novel direction for cancer therapy.
基于非接触细胞的共培养模型经常被用于研究细胞间通讯。然而，这些模型无法准确呈现信号传导的复杂性。d-乳酸是癌细胞产生并释放的一种特殊代谢物。d-乳酸的表征具有挑战性，因为它与l-乳酸质量相同，但含量要低得多。在此，d-α-羟基酸被d-α-羟基酸脱氢酶特异性识别并脱氢。脱氢产物迅速被季铵化以增强质量信号。提出了一种探针上酶促脱氢衍生化方法用于单细胞水平α-羟基酸的手性分析。这是一种有前景的放大方法，能实现超过3个数量级的信号增强。此外，直接接触共培养模型被用于精确模拟肿瘤微环境并探索癌细胞与正常细胞之间的通讯。单细胞质谱（SCMS）被进一步应用于轻松采集细胞提取物，并研究共培养细胞中小分子代谢方面的差异。基于直接接触共培养SCMS，成功检测到了几种差异小分子代谢物以及共培养和单培养正常细胞之间氧化应激的差异。此外，通过这两种开发的方法发现d-乳酸是一种有价值的差异代谢物。它可能解释了正常细胞与癌症相关的代谢行为。d-乳酸代谢相关药物治疗后，这些变化可能会得到缓解。这一发现可能会促进对d-乳酸代谢的研究，这可能为癌症治疗提供一个新方向。
