Homozygous KSR1 deletion attenuates morbidity but does not prevent tumor development in a mouse model of RAS-driven...

Area of Science:

• Oncology
• Molecular Biology
• Cancer Signaling

Background:

• Mitogen-activated protein (MAP) kinase signaling is frequently dysregulated in cancer, leading to therapeutic efforts targeting RAS signaling.
• Kinase Suppressor of Ras 1 (KSR1), a pseudokinase interacting with RAF, is a potential therapeutic target due to its role in RAS-mediated transformation.

Purpose of the Study:

• To investigate the impact of KSR1 deletion on tumor development in a genetically engineered mouse model of pancreatic cancer with oncogenic RAS.
• To evaluate the therapeutic potential of targeting KSR1 in the context of RAS-driven pancreatic cancer.

Main Methods:

• Utilized a genetically engineered mouse model of pancreatic cancer harboring oncogenic RAS.
• Assessed tumor development, morbidity, precursor lesions (PanIN), pERK expression, proliferation, and tumor genetic signatures in Ksr1-/- mice compared to Ksr1+/+ and Ksr1+/- controls.
• Performed RNA sequencing on tumors from different genotypes.

Main Results:

• Ksr1-/- mice exhibited a modest but significant improvement in all-cause morbidity compared to control groups.
• Tumor development and the appearance of precursor pancreatic intraepithelial neoplastic (PanIN) lesions occurred in Ksr1-/- mice, similar to Ksr1+/+ mice.
• No significant differences in pERK expression, proliferation, or unique tumor genetic signatures were observed between Ksr1-/- and control groups.

Conclusions:

• KSR1 deletion offers a modest survival benefit in a RAS-driven pancreatic cancer mouse model but does not fully prevent tumor formation.
• The lack of significant changes in pERK, proliferation, or genetic profiles suggests KSR1's role may be context-dependent or compensated by other pathways.
• Further investigation is required to determine the clinical utility of KSR1 inhibition in cancer therapy, potentially in specific settings or combinations.