The relationship between expression of the sodium/iodide symporter gene and the status of hormonal receptors in human breast cancer tissue.
OBJECTIVE
It has been reported that the sodium/iodide symporter (NIS) gene is expressed in several breast cancer tissues, suggesting the possibility of radionuclide imaging and therapy. However, the regulatory mechanism of NIS gene expression in breast cancer is not yet understood. To assess the relationship between the hormonal status and the NIS expression in breast cancer tissue, we investigated the NIS expression and correlated it to the expression of the thyrotropin receptor (thyroid stimulating hormone receptor, TSH-R), the estrogen receptor (ER) and the progesterone receptor (PR) in human breast cancer tissues.


METHODS
Breast cancer tissues were obtained from 44 patients. Pathological examination showed 2 cases of Grade I, 17 of Grade II, 22 of Grade III, and 3 of unknown grade. We measured the expression of NIS and TSH-R genes by using RT-PCR and we measured the status of ER and PR by using immunohistochemistry.


RESULTS
The NIS gene was expressed in 15 (34%) of the 44 breast cancer tissues. The NIS gene was expressed in 32% of the cases with TSH-R gene expression. The NIS gene was expressed in 40% of the breast cancer tissues with a positive PR and in 31% with a negative PR (p>0.05). It was positive for PR in 18% of the cases and negative for PR in 39% of the cases (p>0.05).


CONCLUSIONS
The NIS gene is expressed in approximately one-third of the human breast cancer tissues. Its expression was not related to the presence of the TSH-R gene or hormonal receptors, ER and PR.
Oh
Hyun Jung
HJ
Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Korea.
Chung
June-Key
JK
Kang
Joo Hyun
JH
Kang
Won Jun
WJ
Noh
Dong Young
DY
Park
In Ae
IA
Jeong
Jae Min
JM
Lee
Dong Soo
DS
Lee
Myung Chul
MC