Keywords

Lung cancer, KRAS, AMG 510, Aquaporin 4, Drug resistance

Abstract

Lung cancer is the leading cause of cancer-related deaths worldwide. One of the most common genetic aberrations in lung cancer patients is Kirsten rat sarcoma viral oncogene homolog (KRAS). The KRAS protein is a Ras superfamily GTPase that switches between an active GTP-bound form and an inactive GDP-bound form. The consequence of KRAS mutations results in constitutively active downstream pathways involved in uncontrolled cell proliferation and survival. Fortunately, there has been a recent development of KRASG12C inhibitors that directly target mutant KRAS, thereby arresting its proliferative effects. A recently FDA-approved KRASG12C inhibitor for the treatment of non-small cell lung cancer, Sotorasib (AMG 510), has been shown to produce insubstantial clinical response rates and a short duration of response. Similar to other targeted therapies, the limitations of this treatment are primarily due to the emergence of drug resistance. Drug resistance has been studied extensively regarding other anticancer treatments; however, the underlying molecular mechanisms remain poorly characterized. Our investigation begins by establishing and analyzing a subpopulation of cancer cells that evolve and mediate drug resistance, known as drug-tolerant persister cells (DTPCs), in KRASG12C mutant cells using AMG 510. First, we observed the reactivation of a pro-proliferative kinase, ERK, in AMG 510 DTPCs. Additionally, whole transcriptomics analysis, RT-qPCR, and immunofluorescent staining demonstrated significant upregulation of AQP4 in AMG 510 DTPCs compared to drug sensitive cells (DSCs). Aquaporin 4 (AQP4) is a water-selective transmembrane protein that regulates fluid homeostasis in many organ systems, including the lungs, and is involved in intracellular calcium signaling. We aim to explore the connections between AQP4, ERK, and calcium signaling in promoting drug tolerance to AMG 510. The insights gained from this research could lead to improved targeted therapies and clinical outcomes by identifying AQP4 as a resistance-driving biomarker.

Completion Date

2024

Semester

Spring

Committee Chair

Zhang, Wencai

Degree

Master of Science (M.S.)

College

College of Medicine

Department

Biomedical Sciences

Degree Program

Biotechnology

Format

application/pdf

Identifier

DP0028300

URL

https://purls.library.ucf.edu/go/DP0028300

Language

English

Rights

In copyright

Release Date

May 2029

Length of Campus-only Access

5 years

Access Status

Masters Thesis (Campus-only Access)

Accessibility Status

Meets minimum standards for ETDs/HUTs

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Restricted to the UCF community until May 2029; it will then be open access.

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