Tp53 haploinsufficiency is involved in hotspot mutations and cytoskeletal remodeling in gefitinib-induced drug-resistant EGFRL858R-lung cancer mice

Yi-Shiang Wang; Ming-Jer Young; Chia-Yu Liu; Yung-Ching Chen; Jan-Jong Hung

doi:10.1038/s41420-023-01393-2

Tp53 haploinsufficiency is involved in hotspot mutations and cytoskeletal remodeling in gefitinib-induced drug-resistant EGFR^L858R-lung cancer mice

Cell Death Discov. 2023 Mar 14;9(1):96. doi: 10.1038/s41420-023-01393-2.

Authors

Yi-Shiang Wang^#¹, Ming-Jer Young^#², Chia-Yu Liu², Yung-Ching Chen², Jan-Jong Hung^{3

4}

Affiliations

¹ Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan.
² Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan.
³ Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan. [email protected].
⁴ Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan. [email protected].

^# Contributed equally.

Abstract

Tumor heterogeneity is the major factor for inducing drug resistance. p53 is the major defender to maintain genomic stability, which is a high proportion mutated in most of the cancer types. In this study, we established in vivo animal models of gefitinib-induced drug-resistant lung cancer containing EGFR^L858R and EGFR^L858R*Tp53^+/- mice to explore the molecular mechanisms of drug resistance by studying the genomic integrity and global gene expression. The cellular morphology of the lung tumors between gefitinib-induced drug-resistant mice and drug-sensitive mice were very different. In addition, in drug-resistant mice, the expression of many cytoskeleton-related genes were changed, accompanied by decreased amounts of actin filaments and increased amounts of microtubule, indicating that significant cytoskeletal remodeling is induced in gefitinib-induced drug-resistant EGFR^L858R and EGFR^L858R*Tp53^+/- lung cancer mice. The gene expression profiles and involved pathways were different in gefitinib-sensitive, gefitinib-resistant and Tp53^+/--mice. Increases in drug resistance and nuclear size (N/C ratio) were found in EGFR^L858R*Tp53^+/- drug-resistant mice. Mutational hotspot regions for drug resistance via Tp53^+/+- and Tp53^+/--mediated pathways are located on chromosome 1 and chromosome 11, respectively, and are related to prognosis of lung cancer cohorts. This study not only builds up a gefitinib-induced drug-resistant EGFR^L858R lung cancer animal model, but also provides a novel mutation profile in a Tp53^+/+- or Tp53^+/--mediated manner and induced cytoskeleton remodeling during drug resistance, which could contribute to the prevention of drug resistance during cancer therapy.