Expression profile of neurotensin receptors in ovarian cancer cell lines

Ovarian cancer is the most common cause of death among the gynecologic malignancies. This outcome is due to the lack of tools for early detection and also effective therapeutic strategies. Neurotensin, is a neuromodulator of dopamine transmission and exerts potent hypothermic and analgesic effects in the brain, whereas in the periphery, neurotensin is a paracrine and endocrine hormone of the digestive tract and of the cardiovascular system. In addition, neurotensin has been shown to stimulate the growth of numerous gastrointestinal tissues including pancreas, gastric antrum, small bowel and colon. Interestingly, neurotensin also acts as a growth factor in a variety of human cancers. Neurotensin fulfills its central and peripheral function through its interaction with three specific receptors: NTR1, NTR2 and NTR3/sortilin. In this study we have investigated five human ovarian cancer cell lines as well as normal ovary tissues for expression of three neurotensin receptors using RT-PCR. We found that NTR1 and NTR3 were expressed in ovarian cancer cell lines while neither of them expressed in normal ovary. Neither of the normal ovary nor the ovarian cancer cell lines expressed NTR2 receptor. The heterodimerization of NTR1 and NTR3 has been shown to be necessary for internalization of neurotensin following activation of downstream signaling cascade. Therefore, we hypothesize that such co-expression of NTR1 and NTR3 might play a functional impact on tumorogenesis of ovarian carcinoma. Furthermore, such ectopic expression in ovarian carcinoma make them possible candidates for developing a more valued diagnostic tool and also possible therapeutic target in patients with ovarian carcinoma.