Attenuated titin protein expression is associated with advanced stages of ovarian cancer

This study explores the role of titin, a giant muscle protein, in the progression of epithelial ovarian cancer (EOC). We examined titin levels in tissues and sera from EOC patients across stages I-IV and in chemoresistant EOC cells. Tissue samples underwent immunohistochemistry, and serum titin levels were measured using ELISA. Quantitative real-time PCR analyzed titin mRNA in cell lines, including chemosensitive, chemoresistant, and normal ovarian cells. Notably, elevated titin levels were detected in 90.9% of stage I tissues compared to only 14.3% of stage III and IV tissues. Serum titin levels were consistently decreased across all stages relative to healthy controls, with a gradual decrease in expression from stages I to IV. Additionally, titin levels were significantly higher in normal ovarian epithelial cells compared to both chemosensitive and chemoresistant EOC cells, albeit significantly higher in chemosensitive than chemoresistant cells. These findings suggest the possible role of decreased titin levels as a marker for therapeutic intervention, particularly in advanced-stage and chemoresistant EOC. Further elucidation of the mechanisms underlying attenuated titin expression holds promise for advancing our understanding of ovarian cancer pathogenesis.