Neurotensin Receptor-1 Expression in Human Prostate Cancer: A Pilot Study on Primary Tumors and Lymph Node Metastases

Neurotensin and its high-affinity receptor, NTR(1), are involved in the growth of various tumors. Few data are available regarding NTR(1) expression in normal and tumoral human prostate tissue samples. NTR(1) expression was assessed using immunohistochemistry in 12 normal prostate tissues, 11 benign prostatic hyperplasia (BPH), 44 prostate cancers, and 15 related metastatic lymph nodes (one per patient, when available). NTR(1)-staining was negative in normal prostate and BPH samples. NTR(1) was overexpressed in four out of 44 (9.1%) primary tumors. There was no clear association between NTR(1) overexpression and age, PSA-values, Gleason score, pT-status, nodal-status, or margin. NTR(1) was expressed at a high level of five out of 15 (33.3%) metastatic lymph nodes. NTR(1) overexpression was thus more frequent in metastatic lymph nodes than in primary tumors (p = 0.038). In this limited series of samples, NTR(1) overexpression was observed in few primary prostate cancers. Upregulation was more frequent in related lymph nodes. The presence of this target in metastatic lymph nodes may open new perspectives for imaging and radionuclide therapy of prostate cancer. Factors driving NTR(1) expression in primary prostate cancer and in nodal and distant metastases still need to be characterized.