IGFBP3 and neoplasm: Immunostaining of tumor sections by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay demonstrated a higher trend of apoptotic cells in IGFBP3-expressing tumor cells (n = 75; 5.08 ± 0.8278% per filed) compared to controls (n = 75; 3.173 ± 0.56% per field; p = 0.0584; Fig. 2e) after IR.