Liou M J, Lin J D, Chan E C, Liu F H, Chao T C, Weng H F
Department of Internal Medicine, Division of Endocrinology and Metabolism, Chang Gung Memorial Hospital, Chang Gung University, 5 Fu-Shin St., Kweishan Village, Taoyuan, PR, Taiwan, China.
Cancer Lett. 2000 Nov 10;160(1):75-80. doi: 10.1016/s0304-3835(00)00565-6.
Human sodium iodide symporter (hNIS) is an intrinsic membrane protein with 12 transmembrane regions, which shows homology to other sodium-dependent transporters. There is controversy as to the amount of hNIS expression in different kinds of human thyroid cancer tissues and cell lines. In this study, reverse transcription-polymerase chain reaction (RT-PCR) was used to detect mRNA of hNIS in various fresh normal, benign tissues and malignant human thyroid tissues. The forward primer was nested hNIS-5' primer containing the sequences: ACCTGGAAATGCGCTTCAGC. The reverse primer was nested hNIS-3' primer containing the sequences: AAGCATGACACCGCGTGCCA. The results revealed three of three normal tissues, six of eight nodular hyperplasia, two of two hyperthyroidism, one of three follicular adenomas, five of ten papillary thyroid carcinomas, one of one follicular carcinoma and zero of one metastatic follicular tissues demonstrated positive results for hNIS in thyroid epithelial cells. A higher percentage of positive results of the symporter mRNA were found in normal benign thyroid tissues and the thyroid tissues of hyperthyroidism, and nodular hyperplasia (84.6%); however follicular adenoma, papillary and follicular thyroid carcinomas demonstrated a lower percentage of expression in the RT-PCR studies (46.7%). Serum thyrotropin levels and the degree of differentiated components presented in cancer tissues have been mentioned as important factors for hNIS expression in the cancer tissues. The discrepancies of the expression of hNIS in in vivo and in vitro studies need further investigation. In conclusion, hNIS was found in higher ratios in normal and benign thyroid tissues than in the malignant tissues. In addition, the RT-PCR technique hNIS did not detect the transporter in most papillary thyroid cancer tissues.
人钠碘同向转运体（hNIS）是一种具有12个跨膜区域的内在膜蛋白，与其他钠依赖性转运体具有同源性。关于hNIS在不同类型的人甲状腺癌组织和细胞系中的表达量存在争议。在本研究中，采用逆转录聚合酶链反应（RT-PCR）检测各种新鲜正常、良性组织及恶性人甲状腺组织中hNIS的mRNA。正向引物为嵌套的hNIS-5'引物，序列为：ACCTGGAAATGCGCTTCAGC。反向引物为嵌套的hNIS-3'引物，序列为：AAGCATGACACCGCGTGCCA。结果显示，在甲状腺上皮细胞中，3例正常组织中的3例、8例结节性增生中的6例、2例甲状腺功能亢进中的2例、3例滤泡性腺瘤中的1例、10例乳头状甲状腺癌中的5例、1例滤泡癌中的1例以及1例转移性滤泡组织中的0例hNIS呈阳性结果。在正常良性甲状腺组织、甲状腺功能亢进的甲状腺组织及结节性增生中，同向转运体mRNA的阳性结果百分比更高（84.6%）；然而，在RT-PCR研究中，滤泡性腺瘤、乳头状和滤泡性甲状腺癌的表达百分比更低（46.7%）。血清促甲状腺激素水平以及癌组织中呈现的分化成分程度已被提及为癌组织中hNIS表达的重要因素。hNIS在体内和体外研究中表达的差异需要进一步研究。总之，在正常和良性甲状腺组织中发现hNIS的比例高于恶性组织。此外，RT-PCR技术在大多数乳头状甲状腺癌组织中未检测到该转运体。
