THE IDENTIFICATION OF <EM>SP4 </EM>MRNA<EM> </EM>AND HSP60 PROTEIN AS BUCCAL CELL BIOMARKERS IN PATIENTS WITH SCHIZOPHRENIA

Schizophrenia (SCZ) is a chronic psychiatric disorder that leads to substantial functional impairment, elevated medical comorbidity, and reduced life expectancy. Despite its prevalence, effective treatments remain limited, and many individuals show inadequate response to available antipsychotic medications. Identifying noninvasive, easily obtainable biomarkers could improve diagnostic precision and guide more personalized interventions. To investigate potential biomarkers, we collected buccal cell samples from individuals with SCZ and healthy controls. Quantitative real-time PCR revealed significant alterations in Sp4 mRNA expression in the SCZ group. In parallel, targeted mass spectrometry showed increased levels of heat shock protein 60 (HSP60), a predicted target of SP4, among patients. We then assessed whether these molecular measures associate with clinical presentation and cognitive dysfunction. Correlation analyses indicated that elevated SP4 mRNA and HSP60 protein levels characterize a subset of patients with more severe symptoms and impaired memory performance. Our data support the use of buccal cell Sp4 mRNA and HSP60 protein as easy-to-collect, candidate SCZ biomarkers.