Department of General Internal Medicine 4, Kawasaki Medical School, Okayama, Japan.
Department of General Internal Medicine 4, Kawasaki Medical School, Okayama, Japan; Kajiki Hospital, Okayama, Japan.
Biochim Biophys Acta Gen Subj. 2024 Oct;1868(10):130675. doi: 10.1016/j.bbagen.2024.130675. Epub 2024 Jul 24.
We investigated the unknown mechanisms of osimertinib-resistant EGFR-mutant lung cancer.
An osimertinib-resistant cell line (PC-9/OsmR2) was established through continuous exposure to osimertinib using an EGFR exon 19 deletion (19Del) lung adenocarcinoma cell line (PC-9). EGFR 19Del (M1), L858R/T790M/C797S (M6), and L858R/C797S (M8) expression vectors were introduced into Ba/F3 cells. A second osimertinib-resistant line (M1/OsmR) was established through continuous exposure to osimertinib using M1 cells.
SLC1A3 had the highest mRNA expression level in PC-9/OsmR2 compared to PC-9 cells by microarray analysis and SLC1A3 was increased by flow cytometry. In PC-9/OsmR2 cells, osimertinib sensitivity was significantly increased in combination with siSLC1A3. Because SLC1A3 functions in glutamic acid transport, osimertinib with a glutaminase inhibitor (CB-839) or an SLC1A3 inhibitor (TFB-TBOA) increased the sensitivity. Also, CB-839 plus TFB-TBOA without osimertinib resulted in greater susceptibility than did CB-839 or TFB-TBOA plus osimertinib. Comprehensive metabolome analysis showed that the M1/OsmR cells had significantly more glutamine and glutamic acid than M1 cells. CB-839 plus osimertinib exerted a synergistic effect on M6 cells and an additive effect on M8 cells.
Targeting glutaminase and glutamic acid may overcome the osimertinib-resistant EGFR-mutant lung cancer.
我们研究了奥希替尼耐药的 EGFR 突变型肺癌的未知机制。
通过用 EGFR 外显子 19 缺失（19Del）肺腺癌细胞系（PC-9）连续暴露于奥希替尼来建立奥希替尼耐药细胞系（PC-9/OsmR2）。将 EGFR 19Del（M1）、L858R/T790M/C797S（M6）和 L858R/C797S（M8）表达载体引入 Ba/F3 细胞。通过用 M1 细胞连续暴露于奥希替尼来建立第二个奥希替尼耐药系（M1/OsmR）。
通过微阵列分析，PC-9/OsmR2 中 SLC1A3 的 mRNA 表达水平比 PC-9 细胞高，通过流式细胞术检测到 SLC1A3 增加。在 PC-9/OsmR2 细胞中，siSLC1A3 与奥希替尼联合使用可显著提高奥希替尼的敏感性。由于 SLC1A3 参与谷氨酸转运，因此用谷氨酰胺酶抑制剂（CB-839）或 SLC1A3 抑制剂（TFB-TBOA）与奥希替尼联合使用可提高敏感性。此外，无奥希替尼时 CB-839 加 TFB-TBOA 比 CB-839 或 TFB-TBOA 加奥希替尼更敏感。综合代谢组学分析表明，M1/OsmR 细胞中的谷氨酰胺和谷氨酸含量明显高于 M1 细胞。CB-839 加奥希替尼对 M6 细胞具有协同作用，对 M8 细胞具有相加作用。
靶向谷氨酰胺酶和谷氨酸可能克服奥希替尼耐药的 EGFR 突变型肺癌。
