BACKGROUNDControl of hypersecretion of certain hormones is one of the key targets in the treatment of pituitary adenomas. RNA interference has been shown to inhibit protein expression, and thus it may represent a promising method for the treatment of pituitary adenomas. In the present study, transfection efficiency of small interfering RNA (siRNA) was optimized in human prolactinoma cells.

METHODSFirst, a method was optimized to extract highly purified human prolactinoma cells in vitro. The extracted cells were verified to retain the physiological features of prolactin (PRL) secretion. Second, three conditions for siRNA transfection were tested by the evaluation of transfection efficiency and cell viability. The proper transfection condition was verified for human prolactinoma cells. Third, the siRNA for prolactin was transfected into the human prolactinoma cells, and the suppression of PRL mRNA was evaluated by quantitative real-time reverse transcription-PCR.

RESULTSThe siRNA of 100 pmol with Lipofectamine 2000 of 5 µl for 1 × 10(6) cells was proved preferable, with transfection efficiency being 53.3% and cell viability being 69.7%. In the preliminary experiment the siRNA against PRL decreased the mRNA of PRL by 34.0%.

CONCLUSIONIt is possible to inhibit hormone hypersecretion by RNA interference, that may eventually enable therapeutic siRNA drugs developed.