DataSheet_1_Co-administration of MDR1 and BCRP or EGFR/PI3K inhibitors overcomes lenvatinib resistance in hepatocellular carcinoma.zip

Lenvatinib is the first-line treatment for hepatocellular carcinoma (HCC), the most common type of primary liver cancer; however, some patients become refractory to lenvatinib. The underlying mechanism of lenvatinib resistance (LR) in patients with advanced HCC remains unclear. We focused on exploring the potential mechanism of LR and novel treatments of lenvatinib-resistant HCC. In particular, we established a Huh7 LR cell line and performed in vitro, bioinformatic, and biochemical assays. Additionally, we used a Huh7-LR cell-derived xenograft mouse model to confirm the results in vivo. Following LR induction, multidrug resistance protein 1 (MDR1) and breast cancer resistance protein (BCRP) transporters were markedly upregulated, and the epidermal growth factor receptor (EGFR), MEK/ERK, and PI3K/AKT pathways were activated. In vitro, the co-administration of elacridar, a dual MDR1 and BCRP inhibitor, with lenvatinib inhibited proliferation and induced apoptosis of LR cells. These effects might be due to inhibiting cancer stem-like cells (CSCs) properties, by decreasing colony formation and downregulating CD133, EpCAM, SOX-9, and c-Myc expression. Moreover, the co-administration of gefitinib, an EGFR inhibitor, with lenvatinib retarded proliferation and induced apoptosis of LR cells. These similar effects might be caused by the inhibition of EGFR-mediated MEK/ERK and PI3K/AKT pathway activation. In vivo, co-administration of lenvatinib with elacridar or gefitinib suppressed tumour growth and angiogenesis. Therefore, inhibiting MDR1 and BCRP transporters or targeting the EGFR/PI3K pathway might overcome LR in HCC. Notably, lenvatinib should be used to treat HCC after LR induction owing to its role in inhibiting tumour proliferation and angiogenesis. Our findings could help develop novel and effective treatment strategies for HCC.

仑伐替尼（Lenvatinib）是原发性肝癌最常见类型——肝细胞癌（hepatocellular carcinoma, HCC）的一线治疗方案，但部分患者会对仑伐替尼产生耐药。晚期HCC患者出现仑伐替尼耐药（lenvatinib resistance, LR）的潜在机制目前仍未阐明。本研究聚焦于探索LR的潜在机制与仑伐替尼耐药HCC的新型治疗策略。具体而言，我们成功构建了Huh7 LR细胞株，并开展了体外实验、生物信息学分析与生化检测。此外，我们利用Huh7-LR细胞来源的异种移植瘤小鼠模型，在体内验证了相关实验结果。在诱导LR后，多药耐药蛋白1（multidrug resistance protein 1, MDR1）与乳腺癌耐药蛋白（breast cancer resistance protein, BCRP）转运体的表达显著上调，同时表皮生长因子受体（epidermal growth factor receptor, EGFR）、MEK/ERK及PI3K/AKT通路被激活。体外实验中，联合应用双重MDR1/BCRP抑制剂埃拉利达（elacridar）与仑伐替尼，可抑制LR细胞的增殖并诱导其凋亡。该作用可能通过抑制癌症干细胞样细胞（cancer stem-like cells, CSCs）的特性实现，具体表现为减少集落形成，并下调CD133、EpCAM、SOX-9及c-Myc的表达水平。此外，联合应用EGFR抑制剂吉非替尼（gefitinib）与仑伐替尼，可延缓LR细胞的增殖并诱导其凋亡。这类相似效应可能源于EGFR介导的MEK/ERK及PI3K/AKT通路激活被抑制。体内实验中，仑伐替尼联合埃拉利达或吉非替尼可抑制肿瘤生长与血管生成。因此，抑制MDR1与BCRP转运体，或靶向EGFR/PI3K通路，或可逆转HCC中的LR。值得注意的是，鉴于仑伐替尼可抑制肿瘤增殖与血管生成，在诱导LR后，仑伐替尼仍可用于HCC的治疗。本研究结果可为HCC新型有效治疗策略的开发提供参考依据。