Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas.
Cancer Discov. 2020 Apr;10(4):608-625. doi: 10.1158/2159-8290.CD-19-0297. Epub 2020 Feb 11.
A hallmark of pancreatic ductal adenocarcinoma (PDAC) is an exuberant stroma comprised of diverse cell types that enable or suppress tumor progression. Here, we explored the role of oncogenic KRAS in protumorigenic signaling interactions between cancer cells and host cells. We show that KRAS mutation (KRAS*) drives cell-autonomous expression of type I cytokine receptor complexes (IL2rγ-IL4rα and IL2rγ-IL13rα1) in cancer cells that in turn are capable of receiving cytokine growth signals (IL4 or IL13) provided by invading Th2 cells in the microenvironment. Early neoplastic lesions show close proximity of cancer cells harboring KRAS* and Th2 cells producing IL4 and IL13. Activated IL2rγ-IL4rα and IL2rγ-IL13rα1 receptors signal primarily via JAK1-STAT6. Integrated transcriptomic, chromatin occupancy, and metabolomic studies identified MYC as a direct target of activated STAT6 and that MYC drives glycolysis. Thus, paracrine signaling in the tumor microenvironment plays a key role in the KRAS*-driven metabolic reprogramming of PDAC. SIGNIFICANCE: Type II cytokines, secreted by Th2 cells in the tumor microenvironment, can stimulate cancer cell-intrinsic MYC transcriptional upregulation to drive glycolysis. This KRAS*-driven heterotypic signaling circuit in the early and advanced tumor microenvironment enables cooperative protumorigenic interactions, providing candidate therapeutic targets in the KRAS* pathway for this intractable disease.
胰腺导管腺癌 (PDAC) 的一个标志是丰富的基质,由多种细胞类型组成,这些细胞类型能够促进或抑制肿瘤的进展。在这里,我们探讨了致癌基因 KRAS 在肿瘤细胞和宿主细胞之间促进肿瘤发生的信号相互作用中的作用。我们表明,KRAS 突变 (KRAS*) 驱动癌症细胞中 I 型细胞因子受体复合物 (IL2rγ-IL4rα 和 IL2rγ-IL13rα1) 的细胞自主表达,而这些受体复合物反过来又能够接收微环境中浸润的 Th2 细胞提供的细胞因子生长信号 (IL4 或 IL13)。早期肿瘤病变显示 KRAS* 携带的肿瘤细胞与产生 IL4 和 IL13 的 Th2 细胞非常接近。激活的 IL2rγ-IL4rα 和 IL2rγ-IL13rα1 受体主要通过 JAK1-STAT6 信号传递。综合转录组学、染色质占据和代谢组学研究表明,MYC 是激活的 STAT6 的直接靶点,并且 MYC 驱动糖酵解。因此,肿瘤微环境中的旁分泌信号在 KRAS驱动的 PDAC 代谢重编程中起着关键作用。意义:肿瘤微环境中的 Th2 细胞分泌的 II 型细胞因子可以刺激癌症细胞内在的 MYC 转录上调,从而驱动糖酵解。这种在早期和晚期肿瘤微环境中由 KRAS驱动的异型信号通路能够促进协同的促肿瘤发生相互作用,为该难治性疾病中 KRAS*途径提供了候选治疗靶点。