Department of Oncology, Tianjin Medical University General Hospital, Tianjin, China.
Tianjin Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, China.
Thorac Cancer. 2021 Jun;12(11):1708-1715. doi: 10.1111/1759-7714.13906. Epub 2021 May 4.
The resistance mechanism of the third generation of epidermal growth factor (EGFR) tyrosine kinase inhibitor (TKI) osimertinib is complex. Epithelial mesenchymal transition (EMT) is a common mechanism of EGFR-TKI acquired resistance. Snail is an important transcription factor related to EMT. Whether targeting Snail can reverse the resistance of osimertinib by downregulating Snail is unknown.
The presence of EMT in H1975/OR (osimertinib resistance) cells was confirmed by transwell assay. To explore the EMT role in resistance, the expression levels of EMT markers were detected in both parental cells H1975 and resistant cells H1975OR. We used RNA interference technology to knockdown the key regulator Snail in resistant cells. After the interference efficiency was confirmed, changes in EMT-related molecules of Snail were explicitly downregulated, and changes in sensitivity and migration and invasion ability were also examined. We used CDK4/6 inhibitor to test the ability of reversing drug resistance by downregulating Snail.
Compared with the H1975 cell line, the H1975/OR resistant cell line showed increased invasiveness, upregulated expression of vimentin and downregulation of E-cadherin. EMT occurred in the H1975/OR resistant cell line. The expression of Snail was upregulated in the osimertinib-resistant cell line H1975/OR. Knockdown of Snail increased the sensitivity of H1975/OR cells to osimertinib. CDK4/6 inhibitor palbociclib could downregulate the expression of Snail. CDK 4/6 inhibitor palbociclib combined with osimertinib could reverse the resistance of osimertinib in H1975/OR.
Snail plays an important role in the third generation of EGFR-TKI osimertinib resistance, which may be reversed by downregulating Snail.
第三代表皮生长因子（EGFR）酪氨酸激酶抑制剂（TKI）奥希替尼的耐药机制复杂。上皮间质转化（EMT）是 EGFR-TKI 获得性耐药的常见机制。Snail 是 EMT 相关的重要转录因子。通过下调 Snail 来靶向 Snail 是否可以逆转奥希替尼的耐药性尚不清楚。
通过 Transwell 实验证实 H1975/OR（奥希替尼耐药）细胞中存在 EMT。为了探讨 EMT 在耐药中的作用，检测亲本细胞 H1975 和耐药细胞 H1975OR 中 EMT 标志物的表达水平。我们使用 RNA 干扰技术敲低耐药细胞中的关键调节因子 Snail。在确认干扰效率后，明确下调 Snail 的 EMT 相关分子，同时检测敏感性和迁移及侵袭能力的变化。我们使用 CDK4/6 抑制剂来测试通过下调 Snail 逆转耐药的能力。
与 H1975 细胞系相比，H1975/OR 耐药细胞系表现出侵袭性增加，波形蛋白表达上调，E-钙黏蛋白表达下调。H1975/OR 耐药细胞系发生 EMT。Snail 在奥希替尼耐药细胞系 H1975/OR 中表达上调。敲低 Snail 增加了 H1975/OR 细胞对奥希替尼的敏感性。CDK4/6 抑制剂 palbociclib 可以下调 Snail 的表达。CDK4/6 抑制剂 palbociclib 联合奥希替尼可逆转 H1975/OR 中奥希替尼的耐药性。
Snail 在第三代 EGFR-TKI 奥希替尼耐药中起重要作用，通过下调 Snail 可能逆转耐药。
