Date of Award
2024
Document Type
Dissertation
Degree Name
Philosophy (Ph.D)
Department
Pharmaceutical Sciences
First Advisor
Zhe-Sheng Chen
Abstract
The resistance of cancer cells to multiple drugs, known as multidrug resistance (MDR), remains a significant obstacle that leads to the ineffectiveness of cancer chemotherapy. The overexpression of ATP-binding cassette (ABC) transporters, particularly ABCB1 and ABCG2, has been strongly correlated with MDR. There is an urgent need to explore and identify novel inhibitors targeting ABCB1 and ABCG2 to overcome the related MDR. Mobocertinib (TAK-788) is an orally administered, irreversible EGFR/HER2 inhibitor approved for the treatment of adult patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) exon 20 insertion mutations. This study reveals that mobocertinib has the potential to reverse ABCB1- and ABCG2-mediated MDR. The molecular docking analysis showed a high binding affinity score for mobocertinib with both ABCB1 and ABCG2 models, signifying the strong interaction between mobocertinib and these two proteins. The MTT assay demonstrated the capability of mobocertinib to reverse MDR mediated by ABCB1 and ABCG2 in cancer cells. In addition, the employment of the HEK293 double-transfected model and the ABCB1 and ABCG2 gene knockout cell model underscored the specific inhibitory effects of mobocertinib on ABCB1- and ABCG2-associated MDR. Mechanistic assays unveiled that mobocertinib enhances drug accumulation by inhibiting the drug efflux function of ABCB1 and ABCG2. This inhibitory effect of mobocertinib on the ATPase activity of ABCB1 and ABCG2 was concentration-dependent. Furthermore, within a treatment period of up to 72 h, mobocertinib demonstrated no influence on the expression levels or subcellular localization of ABCB1 and ABCG2. In the tumor-bearing mouse model, mobocertinib boosted the antitumor effect of topotecan, resulting in tumor regression with the treatment and exhibiting a consistent trend in reversal studies. In summary, our study uncovers a novel potential for repurposing mobocertinib as a dual inhibitor of ABCB1 and ABCG2, and suggests the combination of mobocertinib with substrate drugs as a strategy to counteract MDR.
Recommended Citation
Dong, Xingduo, "MOBOCERTINIB ANTAGONIZES MULTIDRUG RESISTANCE IN ABCB1- AND ABCG2-OVEREXPRESSING CANCER CELLS" (2024). Theses and Dissertations. 815.
https://scholar.stjohns.edu/theses_dissertations/815