Targeting of p21-Activated Kinase 4 Radiosensitizes Glioblastoma Cells via Impaired DNA Repair

• Published in: Cells (Basel, Switzerland) Vol. 11; no. 14; p. 2133
• Main Authors: Blankenstein, Leon J, Cordes, Nils, Kunz-Schughart, Leoni A, Vehlow, Anne
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 06.07.2022; MDPI
• Subjects: Analysis; Antibodies; Brain cancer; Cancer therapies; Care and treatment; Cell culture; Cell cycle; Cell growth; Chemotherapy; Deoxyribonucleic acid; Development and progression; DNA; DNA damage; DNA methylation; DNA repair; Glioblastoma; Glioblastoma cells; Glioblastoma multiforme; GTP-binding protein; Health aspects; Invasiveness; Kinases; Medical prognosis; Microscopy; p21-activated kinase; p21-activated kinase 4; Protein kinases; Proteins; Radiation; radiosensitivity; Radiosensitization; siRNA; X-rays; Germany; United States > US
• ISSN: 2073-4409; 2073-4409
• DOI: 10.3390/cells11142133

Glioblastoma is a devastating malignant disease with poor patient overall survival. Strong invasiveness and resistance to radiochemotherapy have challenged the identification of molecular targets that can finally improve treatment outcomes. This study evaluates the influence of all six known p21-activated kinase (PAK) protein family members on the invasion capacity and radio-response of glioblastoma cells by employing a siRNA-based screen. In a panel of human glioblastoma cell models, we identified PAK4 as the main PAK isoform regulating invasion and clonogenic survival upon irradiation and demonstrated the radiosensitizing potential of PAK4 inhibition. Mechanistically, we show that PAK4 depletion and pharmacological inhibition enhanced the number of irradiation-induced DNA double-strand breaks and reduced the expression levels of various DNA repair proteins. In conclusion, our data suggest PAK4 as a putative target for radiosensitization and impairing DNA repair in glioblastoma, deserving further scrutiny in extended combinatorial treatment testing.