RHOT1‑mediated molecular mechanism of mitochondrial dysfunction and its phenotypic effects on gastric cancer cells

Mitophagy, a selective autophagy process that targets damaged mitochondria, plays a critical role in cellular homeostasis and disease progression, including tumorigenesis. Ras homolog family member T1 (RHOT1), a mitochondria‑associated protein, has been reported to regulate mitochondrial dynamics and energy metabolism. However, its role in gastric cancer (GC) remains unclear. The present study aimed to investigate the function of RHOT1 in GC progression and its mechanistic link with mitochondrial quality control. To achieve this, RHOT1 was silenced in GC cells and its effect on the PINK1/Parkin pathway, mitochondrial homeostasis and cellular behavior examined. The study employed qPCR and western blotting to evaluate gene and protein expression, siRNA transfection to silence RHOT1 and flow cytometry, CCK‑8 proliferation, wound‑healing, and Transwell assays to investigate mitochondrial function and cellular phenotypes. Silencing RHOT1 reduced <i>PINK1</i> mRNA expression by 59.75% (P=0.025) and <i>Parkin</i> mRNA expression by 65.12% (P=0.0189), indicating suppressed mitophagy. This was accompanied by an 84.73% increase in reactive oxygen species (P<0.001) and a 36.94% decrease in mitochondrial membrane potential (P=0.0061). Silencing RHOT1 further caused G₀/G₁ phase arrest and increased apoptosis (P<0.05), thereby markedly inhibiting the proliferation, invasion and migration of GC cells. The present study revealed that RHOT1 drives the malignant phenotype of GC through regulation of mitochondrial quality control and induction of oxidative stress, providing a rationale for developing novel anti‑tumor strategies by targeting mitochondrial function. RHOT1 may serve as a biomarker for prognostic assessment and individualized treatment of GC.