RESUMO
Gonadotropinreleasing hormone (GnRH), or its analogues have been demonstrated to exhibit antiproliferative effects on tumour cells in ovarian, endometrial and breast cancer through GnRHreceptors (GnRHR). However, the role of GnRH in nasopharyngeal carcinoma (NPC) remains to be elucidated. In order to investigate the effects of GnRH in NPC, the present study examined the expression of the GnRHR transcript in NPC and investigated the phenotypic changes in HK1 cells, a recurrent NPCderived cell line, upon receiving GnRH treatment. Firstly, the GnRHR transcript was demonstrated in the NPC cell lines and four snap frozen biopsies using reverse transcriptionquantitative polymerase chain reaction. In addition, immunohistochemistry revealed the expression of GnRHR in two of the eight (25%) NPC specimens. Treatment with GnRH induced a rapid increase in intracellular ionised calcium concentration in the NPC cells. GnRH and its agonists, triptorelin and leuprolide, exerted antiproliferative effects on the NPC cells, as determined using an MTS assay. GnRH did not induce any cell cycle arrest in the HK1 cells under the conditions assessed in the present study. Timelapse imaging demonstrated a reduction in cell motility in the GnRHtreated cells. In conclusion, GnRH, or its analogues may have antitumour effects on NPC cells. The consequences of alterations in the levels of GnRH on the progression of NPC require further examination.