TY - JOUR TI - IGF-IEc expression is increased in secondary compared to primary foci in neuroendocrine neoplasms AU - Alexandraki, K.I. AU - Philippou, A. AU - Boutzios, G. AU - Theohari, I. AU - Koutsilieris, M. AU - Delladetsima, I.K. AU - Kaltsas, G.A. JO - OncoTargets and therapy PY - 2017 VL - 8 TODO - 45 SP - 79003-79011 PB - Impact Journals, LLC SN - null TODO - 10.18632/oncotarget.20743 TODO - insulin like growth factor IEc; isoprotein; Ki 67 antigen; somatomedin C; unclassified drug, adult; Article; cancer localization; carcinogenesis; clinical article; controlled study; female; human; human tissue; immunohistochemistry; male; middle aged; neuroendocrine carcinoma; protein determination; protein expression; protein function; protein targeting; tumor biopsy; upregulation TODO - Different Insulin-like growth factor-I (IGF-I) mRNA transcripts are produced by alternative splicing and particularly the IGF-IEc isoform has been implicated in the development and/or progression of various types of cancer. In the present study, we examined the potential role of IGF-IEc expression as a new immunohistochemical marker of aggressiveness in neuroendocrine neoplasms (NENs). We utilized immunohistochemical analysis in tissue specimens of 47 patients with NENs, to evaluate the expression of IGF-IEc (%) and Ki-67 proliferation index (%). Specimens from patients with tumors of different tissue origin, of either primary or metastatic lesions and of different grade were examined. Cytoplasmic IGF-IEc staining was found in 23 specimens of NENs or NECs: 10 pancreatic, 4 small bowel, 3 gastric, 1 lung, 1 uterine and 4 poorly differentiated of unknown primary origin. Ki-67 and IGF-IEc expression was positively correlated in all the samples studied (r=0.31, p=0.03). IGF- 1Ec expression was more prevalent in specimens originating from metastatic foci with high Ki-67 compared to primary sites with low Ki-67 expression (p=0.036). These findings suggest a possible role of IGF-IEc in NEN tumorigenesis and progression to metastases that could be used as an additional new marker of a more aggressive behavior and a potential drugable target. © Alexandraki et al. ER -