The gastrin-releasing peptide receptor as a potential biomarker for squamous cell carcinoma

The gastrin-releasing peptide receptor (GRPR) is expressed across multiple human cancer types, including head and neck tumors, and has also been detected in the oral mucosa of patients bearing head and neck neoplasms. This study aimed to evaluate GRPR expression in tumor samples obtained from patients with histopathologically confirmed squamous cell carcinomas of the head and neck and esophagus. GRPR protein expression was analyzed by immunohistochemistry in 80 tumor specimens and 10 cancer-free tissue samples. GRPR positivity was observed in 72.5% of tumors, whereas all healthy control samples were negative. Additionally, an expression threshold of 10% was sufficient to distinguish between positive and negative tumors (P < 0.0001). Overall survival for the cohort was 64.7%. GRPR expression tends to influence patient outcomes, with an expression level exceeding 50% correlating with worse survival (p = 0.031). GRPR is overexpressed in head and neck and esophageal squamous cell carcinoma, and higher expression was associated with worse survival, suggesting a promising role of GRPR as a new biomarker for early diagnosis and prognosis.