Heterogeneous populations within a tumor have varying metabolic profiles, which can muddle the interpretation of bulk tumor imaging studies of treatment response. Although methods to study tumor metabolism at the cellular level are emerging, these methods provide a single time point “snapshot” of tumor metabolism and require a significant time and animal burden while failing to capture the longitudinal metabolic response of a single tumor to treatment. Here, we investigated a novel method for longitudinal, single-cell tracking of metabolism across heterogeneous tumor cell populations using optical metabolic imaging (OMI), which measures autofluorescence of metabolic coenzymes as a report of metabolic activity. We also investigated whether in vivo cellular metabolic heterogeneity can be accurately captured using tumor-derived three-dimensional organoids in a genetically engineered mouse model of breast cancer. OMI measurements of response to paclitaxel and the phosphatidylinositol-3-kinase inhibitor XL147 in tumors and organoids taken at single cell resolution revealed parallel shifts in metaboltruic heterogeneity. Interestingly, these previously unappreciated heterogeneous metabolic responses in tumors and organoids could not be attributed to tumor cell fate or varying leukocyte content within the microenvironment, suggesting that heightened metabolic heterogeneity upon treatment is largely due to heterogeneous metabolic shifts within tumor cells. Together, these studies show that OMI revealed remarkable heterogeneity in response to treatment, which could provide a novel approach to predict the presence of potentially unresponsive tumor cell subpopulations lurking within a largely responsive bulk tumor population, which might otherwise be overlooked by traditional measurements.

肿瘤中的异质种群具有不同的代谢谱，这可能使对治疗反应的大块肿瘤成像研究的解释混乱。尽管正在研究在细胞水平上进行肿瘤代谢的方法，但是这些方法提供了肿瘤代谢的单个时间点“快照”，并且需要大量的时间和动物负担，同时无法捕获单个肿瘤对治疗的纵向代谢反应。在这里，我们研究了使用光学代谢成像（OMI）跨异质性肿瘤细胞群体进行纵向，单细胞代谢追踪的新方法，该方法可测量代谢辅酶的自发荧光，作为代谢活动的报告。我们还调查了是否在体内细胞代谢异质性可以在肿瘤的基因工程小鼠模型中使用肿瘤衍生的三维类器官来精确捕获。在单细胞分辨率下对肿瘤和类器官中对紫杉醇和磷脂酰肌醇-3-激酶抑制剂XL147的响应的OMI测量显示，代谢异质性平行变化。有趣的是，这些先前未认识到的肿瘤和类器官中的异质代谢反应不能归因于肿瘤细胞命运或微环境中白细胞含量的变化，这表明治疗后代谢异质性的提高很大程度上归因于肿瘤细胞内异质代谢的改变。这些研究共同表明，OMI显示出对治疗的显着异质性，