Expression of Cold-Inducible RNA-Binding Protein (CIRP) in Pituitary Adenoma and its Relationships with Tumor Recurrence

BACKGROUND: The aim of this study was to detect the expression of cold-inducible RNA-binding protein in pituitary adenoma and to determine its effects on tumor recurrence. MATERIAL/METHODS: We collected a total of 60 post-op samples collected from pituitary adenoma patients (including 20 cases of invasive pituitary adenoma, 20 cases of non-invasive adenoma, and 20 cases of non-invasive recurrent adenoma) admitted in our hospital. Both protein and mRNA levels of CIRP in 3 types of pituitary adenoma samples were quantified by Western blotting and real-time PCR, respectively. RESULTS: Western blotting revealed significantly elevated CIRP expression levels in invasive pituitary adenoma compared to non-invasive tumors, with statistical significance (p<0.05). Recurrent pituitary adenoma expressed significantly higher CIRP levels compared to non-recurrent tumors (p<0.05). Real-time PCR for CIRP mRNA obtained consistent results: transcript levels were significantly higher in invasive pituitary adenoma compared to non-invasive adenoma (p<0.05); recurrent adenoma also had significantly higher CIRP mRNA levels compared to non-recurrent tumors (p<0.05). Among all 3 types of pituitary adenoma, recurrent tumors had the highest levels of CIRP mRNA and protein. CONCLUSIONS: The expression of CIRP in pituitary adenoma is closely related with tumor proliferation and invasion, and its significantly elevated expression level indicates post-op recurrence.