Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35233, USA.
HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA.
Cells. 2022 Jun 9;11(12):1873. doi: 10.3390/cells11121873.
Glioblastoma (GBM) remains one of the most aggressive cancers, partially due to its ability to migrate into the surrounding brain. The sphingolipid balance, or the balance between ceramides and sphingosine-1-phosphate, contributes to the ability of GBM cells to migrate or invade. Of the ceramidases which hydrolyze ceramides, acid ceramidase (ASAH1) is highly expressed in GBM samples compared to non-tumor brain. ASAH1 expression also correlates with genes associated with migration and focal adhesion. To understand the role of ASAH1 in GBM migration, we utilized shRNA knockdown and observed decreased migration that did not depend upon changes in growth. Next, we inhibited ASAH1 using carmofur, a clinically utilized small molecule inhibitor. Inhibition of ASAH1 by carmofur blocks in vitro migration of U251 (GBM cell line) and GBM cells derived from patient-derived xenografts (PDXs). RNA-sequencing suggested roles for carmofur in MAPK and AKT signaling. We found that carmofur treatment decreases phosphorylation of AKT, but not of MAPK. The decrease in AKT phosphorylation was confirmed by shRNA knockdown of ASAH1. Our findings substantiate ASAH1 inhibition using carmofur as a potential clinically relevant treatment to advance GBM therapeutics, particularly due to its impact on migration.
胶质母细胞瘤（GBM）仍然是最具侵袭性的癌症之一，部分原因是其能够迁移到周围的大脑中。神经酰胺和鞘氨醇-1-磷酸之间的神经鞘脂平衡，有助于 GBM 细胞迁移或侵袭的能力。在水解神经酰胺的神经酰胺酶中，酸性神经酰胺酶（ASAH1）在 GBM 样本中的表达水平明显高于非肿瘤脑。ASAH1 的表达也与与迁移和黏附焦点相关的基因相关。为了了解 ASAH1 在 GBM 迁移中的作用，我们利用 shRNA 敲低技术观察到迁移减少，而这种减少并不依赖于生长的变化。接下来，我们使用卡莫氟抑制 ASAH1，卡莫氟是一种临床上使用的小分子抑制剂。卡莫氟抑制 ASAH1 可阻断 U251（GBM 细胞系）和源自患者来源异种移植（PDX）的 GBM 细胞的体外迁移。RNA 测序表明卡莫氟在 MAPK 和 AKT 信号通路中发挥作用。我们发现卡莫氟处理可降低 AKT 的磷酸化，但不降低 MAPK 的磷酸化。ASAH1 的 shRNA 敲低证实了 AKT 磷酸化的减少。我们的研究结果证实了使用卡莫氟抑制 ASAH1 作为一种潜在的临床相关治疗方法来推进 GBM 治疗，特别是由于其对迁移的影响。
