Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, 68198-5870, USA.
Department of Pharmacy Practice and Science, College of Pharmacy, University of Nebraska Medical Center, 986145 Nebraska Medical Center, Omaha, NE, 68198-6145, USA.
Oncogene. 2021 Jan;40(1):215-231. doi: 10.1038/s41388-020-01518-2. Epub 2020 Oct 27.
Pancreatic ductal adenocarcinoma (PDAC) metastasizes to distant organs, which is the primary cause of mortality; however, specific features mediating organ-specific metastasis remain unexplored. Emerging evidence demonstrates that cancer stem cells (CSCs) and cellular metabolism play a pivotal role in metastasis. Here we investigated the role of distinct subtypes of pancreatic CSCs and their metabolomic signatures in organ-specific metastatic colonization. We found that PDAC consists of ALDH+/CD133+ and drug-resistant (MDR1+) subtypes of CSCs with specific metabolic and stemness signatures. Human PDAC tissues with gemcitabine treatment, autochthonous mouse tumors from Kras; Pdx1-Cre (KC) and Kras; Trp53; Pdx-1 Cre (KPC) mice, and KPC- Liver/Lung metastatic cells were used to evaluate the CSC, EMT (epithelial-to-mesenchymal transition), and metabolic profiles. A strong association was observed between distinct CSC subtypes and organ-specific colonization. The liver metastasis showed drug-resistant CSC- and EMT-like phenotype with aerobic glycolysis and fatty acid β-oxidation-mediated oxidative (glyco-oxidative) metabolism. On the contrary, lung metastasis displayed ALDH+/CD133+ and MET-like phenotype with oxidative metabolism. These results were obtained by evaluating FACS-based side population (SP), autofluorescence (AF+) and Alde-red assays for CSCs, and Seahorse-based oxygen consumption rate (OCR), extracellular acidification rate (ECAR), and fatty acid β-oxidation (FAO)-mediated OCR assays for metabolic features along with specific gene signatures. Further, we developed in vitro human liver and lung PDAC metastasis models by using a combination of liver or lung decellularized scaffolds, a co-culture, and a sphere culture methods. PDAC cells grown in the liver-mimicking model showed the enrichment of MDR1+ and CPT1A+ populations, whereas the PDAC cells grown in the lung-mimicking environment showed the enrichment of ALDH+/CD133+ populations. In addition, we observed significantly elevated expression of ALDH1 in lung metastasis and MDR1/LDH-A expression in liver metastasis compared to human primary PDAC tumors. Our studies elucidate that distinct CSCs adapt unique metabolic signatures for organotropic metastasis, which will pave the way for the development of targeted therapy for PDAC metastasis.
胰腺导管腺癌 (PDAC) 转移到远处器官，这是导致死亡的主要原因；然而，介导器官特异性转移的特定特征仍未得到探索。新出现的证据表明，癌症干细胞 (CSC) 和细胞代谢在转移中起着关键作用。在这里，我们研究了不同亚型的胰腺 CSC 及其代谢组学特征在器官特异性转移性定植中的作用。我们发现 PDAC 由 ALDH+/CD133+ 和耐药 (MDR1+) 亚型的 CSC 组成，具有特定的代谢和干性特征。我们使用经吉西他滨处理的人 PDAC 组织、来自 Kras; Pdx1-Cre (KC) 和 Kras; Trp53; Pdx-1 Cre (KPC) 小鼠的自发肿瘤，以及 KPC-肝/肺转移性细胞来评估 CSC、EMT（上皮间质转化）和代谢特征。我们观察到不同的 CSC 亚型与器官特异性定植之间存在很强的关联。肝转移显示出耐药性 CSC 和 EMT 样表型，具有有氧糖酵解和脂肪酸 β-氧化介导的氧化（糖氧化）代谢。相反，肺转移显示出 ALDH+/CD133+ 和 MET 样表型，具有氧化代谢。这些结果是通过评估基于 FAC 的侧群 (SP)、自发荧光 (AF+) 和 Alde-red 测定法对 CSC 进行评估，以及基于 Seahorse 的耗氧量 (OCR)、细胞外酸化率 (ECAR) 和脂肪酸 β-氧化 (FAO) 介导的 OCR 测定法对代谢特征以及特定的基因特征进行评估而得出的。此外，我们通过使用肝或肺去细胞化支架、共培养和球体培养方法的组合，开发了体外人肝和肺 PDAC 转移模型。在肝模拟模型中生长的 PDAC 细胞显示出 MDR1+和 CPT1A+群体的富集，而在肺模拟环境中生长的 PDAC 细胞显示出 ALDH+/CD133+群体的富集。此外，与原发性人 PDAC 肿瘤相比，我们观察到肺转移中 ALDH1 的表达显著升高，而肝转移中 MDR1/LDH-A 的表达升高。我们的研究阐明了不同的 CSC 为器官趋向性转移适应独特的代谢特征，这将为 PDAC 转移的靶向治疗铺平道路。
