PLEKHF1 Induces Mitochondrial Dysfunction to Inhibit Osteosarcoma Growth and Metastasis

Osteosarcoma (OS) is an uncommon malignancy with stagnant survival rates over the past four decades and early-stage metastasis, predominantly affecting children and adolescents. This study identified significant metabolic differences between metastatic and non-metastatic OS samples through bioinformatics analysis, highlighting key processes such as cell proliferation, mitochondrial assembly, and changes in mitochondrial membrane permeability. Among differentially expressed genes, Pleckstrin Homology And FYVE Domain Containing 1 (PLEKHF1) was the most significantly downregulated in metastatic OS samples. Functional experiments demonstrated that PLEKHF1 overexpression in Saos-2 and U2OS cells induced mitochondrial dysfunction, evidenced by increased mtROS levels, decreased mitochondrial membrane potential, and altered cytochrome C distribution. Additionally, PLEKHF1 overexpression inhibited OS cell viability, colony formation, migration, invasion, and epithelial-mesenchymal transition (EMT), while promoting apoptosis. Conversely, knockdown of PLEKHF1 had the opposite effects on Saos-2 and U2OS cells. In vivo, PLEKHF1 overexpression reduced tumor growth and lung metastasis in a mouse model. Conversely, PLEKHF1 knockdown ameliorated Rotenone-induced mitochondrial dysfunction and mitophagy, partially reversing the suppressive effects of Rotenone on OS cell aggressiveness. These findings suggest that PLEKHF1 could serve as an anti-tumor factor by inducing mitochondrial dysfunction, thereby inhibiting OS growth and metastasis. The study highlights the potential of PLEKHF1 as a therapeutic target for managing osteosarcoma, providing valuable insights into the role of mitochondrial dysfunction in OS pathogenesis.