瘤内缺氧与去势抵抗性前列腺癌 (CRPC) 这种致命疾病有关。FOXA1 是一种在 CRPC 中下调的上皮转录因子。我们之前曾报道过,FOXA1 缺失会通过升高的 TGFβ 信号传导诱导上皮-间质转化 (EMT) 和细胞运动。然而,FOXA1 是否直接调节 CRPC 肿瘤的缺氧通路之前尚未研究。在这里,我们报告 FOXA1 下调诱导缺氧转录程序,并且 FOXA1 水平与临床前列腺癌 (PCa) 样本中的缺氧标志物呈负相关。从机制上讲,FOXA1 直接与 HIF1A 的基因内增强子结合以抑制其表达,而 HIF1A 反过来又在介导 FOXA1 缺失诱导的缺氧基因表达中起关键作用。此外,我们确定了 CCL2,一种调节肿瘤微环境并促进癌症进展的趋化因子配体,作为 FOXA1-HIF1A 轴的重要靶点。我们发现 FOXA1 缺失导致免疫抑制性巨噬细胞浸润和细胞侵袭增加,这取决于 HIF1A 表达。至关重要的是,使用药理学抑制剂治疗靶向 HIF1A-CCL2 可消除 FOXA1 丢失诱导的巨噬细胞浸润和 PCa 细胞侵袭。总之,我们的研究揭示了 FOXA1 在控制缺氧肿瘤微环境中的重要作用,并将 HIF1A-CCL2 轴确立为 FOXA1 缺失诱导的 CRPC 进展的一种机制。依赖于 HIF1A 的表达。至关重要的是,使用药理学抑制剂治疗靶向 HIF1A-CCL2 可消除 FOXA1 丢失诱导的巨噬细胞浸润和 PCa 细胞侵袭。总之,我们的研究揭示了 FOXA1 在控制缺氧肿瘤微环境中的重要作用,并将 HIF1A-CCL2 轴确立为 FOXA1 缺失诱导的 CRPC 进展的一种机制。依赖于 HIF1A 的表达。至关重要的是,使用药理学抑制剂治疗靶向 HIF1A-CCL2 可消除 FOXA1 丢失诱导的巨噬细胞浸润和 PCa 细胞侵袭。总之,我们的研究揭示了 FOXA1 在控制缺氧肿瘤微环境中的重要作用,并将 HIF1A-CCL2 轴确立为 FOXA1 缺失诱导的 CRPC 进展的一种机制。
"点击查看英文标题和摘要"
FOXA1 inhibits hypoxia programs through transcriptional repression of HIF1A
Intratumoral hypoxia is associated with castration-resistant prostate cancer (CRPC), a lethal disease. FOXA1 is an epithelial transcription factor that is down-regulated in CRPC. We have previously reported that FOXA1 loss induces epithelial-mesenchymal transition (EMT) and cell motility through elevated TGFβ signaling. However, whether FOXA1 directly regulates hypoxia pathways of CRPC tumors has not been previously studied. Here we report that FOXA1 down-regulation induces hypoxia transcriptional programs, and FOXA1 level is negatively correlated with hypoxia markers in clinical prostate cancer (PCa) samples. Mechanistically, FOXA1 directly binds to an intragenic enhancer of HIF1A to inhibit its expression, and HIF1A, in turn, is critical in mediating FOXA1 loss-induced hypoxia gene expression. Further, we identify CCL2, a chemokine ligand that modulates tumor microenvironment and promotes cancer progression, as a crucial target of the FOXA1-HIF1A axis. We found that FOXA1 loss leads to immunosuppressive macrophage infiltration and increased cell invasion, dependent on HIF1A expression. Critically, therapeutic targeting of HIF1A-CCL2 using pharmacological inhibitors abolishes FOXA1 loss-induced macrophage infiltration and PCa cell invasion. In summary, our study reveals an essential role of FOXA1 in controlling the hypoxic tumor microenvironment and establishes the HIF1A-CCL2 axis as one mechanism of FOXA1 loss-induced CRPC progression.