Correlation between sodium-iodide symporter expression and circulating tumor cell positivity in differentiated thyroid carcinoma

Objective We investigated the correlation between the expression of the sodium-iodide symporter(NIS) and the detection of circulating tumor cells(CTCs) in differentiated thyroid carcinoma(DTC).Methods NIS expression in differentiated thyroid and the positive rate of CTCs in the peripheral blood were determined by immunohistochemistry S-P and flow cytometry from the records of 172 cases of differentiated thyroid carcinoma.Results Seventy-six cases(44.2%) expressed NIS in the differentiated thyroid and 63 cases(36.6%) were positive for CTCs in the peripheral blood. There was a significant difference between N0 and N1 in the expression of NIS(χ~2 = 6.015, P = 0.014) and the positive rate of CTCs(χ~2 = 14.035, P = 0.001). N0 and N1 also differed significantly in the expression of NIS(r =-0.383,-0.610, P = 0.002, < 0.001). The differences in the NIS expression, but not in the positive rate of CTCs, were significant among the different pathological subtypes(χ~2 = 7.897, P = 0.005; χ~2 = 1.455, P = 0.228, respectively). There was a significant negative correlation between the highly differentiated type and intermediate differentiation type both in the expression of NIS and positive rate of CTCs(r =-0.591,-0.443, P < 0.001, P = 0.002). Conclusion There was a significant negative correlation between the expression of tissue NIS and positive rate of CTCs in the peripheral blood in DTC. The malignancy level and lymph node metastasis in differentiated thyroid carcinoma were negatively correlated with NIS expression and positively correlated with the positive rate of CTC.

Adenovirus-mediated and tumor-specific transgene expression of the sodium-iodide symporter from the human telomerase reverse transcriptase promoter enhances killing of lung cancer cell line in vitro

Background The sodium-iodide symporter （NIS） protein can mediate the active radioiodine uptake.The human telomerase reverse transcriptase （hTERT） promoter is known to be selectively reactivated in majority of tumors and hence could be used for tumor targeting.We constructed a recombinant adenovirus containing the human sodium iodide symporter （hNIS） gene directed by the hTERT promoter, characterized the ability of infected cells in uptaking iodide, and explored the therapeutic efficacy of 131I in a lung cancer cell line in vitro.Methods The hTERT promoter was amplified by PCR from DNA isolated from log-phase HepG2 cells, subcloned into lineralized FL＊-hNIS/pcDNA3, and then the hTERT-hNIS sequence was subcloned into the shuttle plasmid pAdTrack.The recombinant adenovirus Ad-hTERT-hNIS was constructed by AdEasy system.A positive control adenovirusAd-CMV-hNIS and a negative control adenovirus Ad-CMV were created similarly.A549 cells were transduced with recombinant adenoviruses.125I uptake studies and sodium perchlorate suppression studies were used to confirm hNIS expression and function.Toxic effects of 131I on tumor cells were studied by in vitro clonogenic assay.Results We first successfully constructed an adenovirus mediated transgene expression system of the hNIS under the control of hTERT promoter.When infected with recombinant adenovirus constructs expressing hNIS directed by hTERTand CMV-promoters （Ad-hTERT-hNIS and Ad-CMV-hNIS, respectively）, the lung cancer cell line A549 had increased ability to uptake radioiodide up to 23- and 30- fold compared to the control parental cells, respectively.The radioiodide uptake ability of both the Ad-CMV-hNIS and Ad-hTERT-hNIS transduced cell lines were repressed 11-fold by sodium perchlorate （NaCIO4）.The subsequent in vitro clonogenic assay of the infected A549 cell line was further repressed to 23% （Ad-CMV-hNIS） and 30% （Ad-hTERT-hNIS） of the control group after receiving radioiodide for 7 hours （P 〈0.001）.Conclusion Our preliminary study indicates that an adenovirus mediated transgene expression system of the hNIS under the control of hTERT promoter has the potential to become an effective wide-spectrum yet highly specific anti-cancer strategy.

Radioiodine therapy for castration-resistant prostate cancer following prostate-specific membrane antigen promoter-mediated transfer of the human sodium iodide symporter

Radioiodine therapy, the most effective form of systemic radiotherapy available, is currently useful only for thyroid cancer because of the thyroid-specific expression of the human sodium iodide symporter （hNIS）. Here, we explore the efficacy of a novel form of gene therapy using prostate-specific membrane antigen （PSMA） promoter-mediated hNIS gene transfer followed by radioiodine administration for the treatment of castration-resistant prostate cancer （CRPC）. The androgen-dependent C33 LNCaP cell line and the androgen-independent C81 LNCaP cell line were transfected by adenovirus. PSMA promoter-hNIS （Ad.PSMApro-hNIS） or adenovirus.cytomegalovirus-hNIS containing the cytomegalovirus promoter （Ad.CMM-hNIS） or a control virus. The iodide uptake was measured in vitro. The in vivo iodide uptake by C81 cell xenografts in nude mice injected with an adenovirus carrying the hNIS gene linked to PSMA and the corresponding tumor volume fluctuation were assessed. Iodide accumulation was shown in different LNCaP cell lines after Ad.PSMApro-hNIS and Ad.CMV-hNIS infection, but not in different LNCaP cell lines after adenovirus.cytomegalovirus （Ad.CMV） infection. At each time point, higher iodide uptake was shown in the C81 cells infected with Ad.PSMApro-hNIS than in the C33 cells （P 〈 0.05）. An in vivo animal model showed a significant difference in 1311 radioiodine uptake in the tumors infected with Ad.PSMApro-hNIS, Ad.CMV-hNIS and control virus （P 〈 0.05） and a maximum reduction of tumor volume in mice infected with Ad.PSMApro-hNIS. These results show prostate-specific expression of the hNIS gene delivered by the PSMA promoter and effective radioiodine therapy of CRPC by the PSMA promoter-driven hNIS transfection.

Effect of Cytokine on the Expression of Sodium Iodide Symporter Gene in Breast Cancer Cell

Objective: To investigate the effect of cytokines (TNF-α,IFN-γ and IL-6) on the expression of sodium-iodide symporter(NIS)gene in breast cancer cell(MCF-7). Methods:The breast cancer cell was cultureds with negative control culture or culture with different concentrations of cytokines for 72 h.NIS gene mRNA in breast cancer cells cultured was determined by reverse transcriptase-polymerase chain reaction(RT-PCR). Results:Expression of sodium-iodide symporter mRNA can be found decreasing along with increasing the concentration of cytokine dose-dependently. Conclusion: Cytokine may play a role in iodide-uptake modulating in breast cancer cells by their effect on NIS gene expression.

Transfection of the Human Sodium/Iodide Symporter(NIS) Gene with Liposomes and the Expression of the NIS Protein in Human Lung A549 Cancer Cells

OBJECTIVE To examine the possibility of human sodium iodide symporter （hNIS） protein expression in lung cancer cells. METHODS Human lung A549 cancer cells were thawed and cultured in vitro. The cells were divided into an experimental group transfected with a recombinant pcDNA3-hNIS plasmid and a control group transfected only with a pcDNA3 plasmid. The recombinant plasmid vector encoding the hNIS gene （pcDNA3-hNIS） was amplified, purified and identified. The hNIS gene was followed by DNA sequencing. A Western blot and an immunohistochemical assay were applied to detect the hNIS protein expression in the transfected human lung A549 cancer cells. RESULTS Restriction enzyme digestion and DNA sequencing results showed the size and direction of the inserted gene in the recombinant pcD- NA3-hNIS plasmid was correct. The Western blot method and immunohistochemical analysis showed a positive NIS protein expression in the experimental group. The NIS protein was detected mainly in the cell membranes showing a positive rate up to 70.6% with no expression of the NIS protein in the control group. There was a significant difference between two groups （P=0.000）. CONCLUSION The hNIS gene was transfected effectively into human lung A549 cancer cells mediated by Lipofectamine 2000, and was expressed with its protein in vitro.

Radioiodide uptake in melanoma cells after transfer of human NaI symporter gene

To obtain human sodium/iodide symporter gene cDNA for studying its potential ability as a radioiodide treatment for melanoma, the hNIS gene cDNA was amplified with total RNA from human thyroid tissue by RT-PCR. The hNIS cDNA was inserted into cloning vector pUCm-T and subcloned into eukaryotic expression vector pc-DNA3. The pc-DNA3-hNIS and pc-DNA3 were transduced into melanoma cells (B16) by electroporation, and two cell lines termed B16-A and B16-B respectively were established. The uptake and efflux of iodide was examined in vitro. The three cell lines (B16-A, B16-B, B16) were injected subcutaneously into the right flank of C57 mice. Biodistribution study and tumor imaging were performed when the tumor reached approximately 10mm in diameter. The cloned hNIS cDNA sequence was identical with the published sequence. Two novel cell lines named 16-A containing pc-DNA3-hNIS and B16-B containing pc-DNA3 only were established. The resultant cell line B16-A accumulated 17 and 19 times more radioiodide in vitro than B16 and B16-B respectively. The iodide uptake reached the half-maximal level within 10 min, and reached a plateau at 30 min. The efflux of iodide was also rapid (T1/2eff=10min). The imaging shows in vivo uptake in expected sites including the salivary glands, thyroid, stomach, and hNIS-transduced tumor, whereas the nontransduced tumor was not visualized. The %ID/g of B16-A tumors at 1, 2, 4, 12, and 24h after injec- tion of 125I were 12.22±0.71, 10.91±0.72, 8.73±0.99, 1.24±0.29, and 0.19±0.03, respectively, which were signifi- cantly higher percentages than those for controlling tumors, p<0.01. However, biologic T1/2 was about 6 h. Our pre- liminary data indicate that the transduction of the hNIS gene per se is sufficient to induce iodide transport in mela- noma cells both in vitro and in vivo, but T1/2eff is short.

Radiofrequency induction on sodium/iodide symporter expression of thyroid cancer

Objective; The aim of this study was to investigate the effects of radiofrequency treatment on sodium/iodide symporter expression of thyroid cancer ceils. Methods： In 29 thyroid cancer patients with low or no expression of soda ／ iodide symporter, the radio frequency combined 1311 therapy was used, the whole-body scintigraphy and serum Ig were detected before and after the radiofrequency treatment. Results： The whole-body scintigraphy showed that 4 cases （4/29） before radiofrequenc_y treatment had positive iodine uptake, 19 cases （19/29） two weeks after radiofrequency treatment had the positive iodine uptake, 12 cases （12/29） four weeks after radiofrequency treatment had the positive iodine uptake. Four weeks after radiofrequency treatment, 5 cases had increased serum Ig levels, 17 cases had decreased serum Ig levels, 7 cases showed no change. 25 cases （25/29） were effective, 15 cases （15/29） were cured. Conclusion： The radiofrequency induced the non-expressed the sodium/iodide symporter of thyroid cancer cells regain the iodine intake ability, it improved the clinical efficacy of 131I therapy in dedifferentiated thyroid cancer.

Correlation analysis between serum β2-MG and sodium/iodide symporter in patients with thyroid carcinoma

Objective： The aim of our study was to investigate the correlation between the expression of sodium/iodide symporter, serum levels of β2-MG and prognosis of thyroid carcinoma patients. Methods： Ninty-five cases with thyroid carcinoma, using enzyme-linked immunosorbent assay with double-antibody sandwich to detect the serum β2-MG levels and immunehistochemistry to detect NIS expression of thyroid cancer tissue. Results： Thirty-seven cases showed positive expression of sodium/iodide symporter （38.9%） and 30 cases showed positive expression of β2-MG （31.57%）. There were significant differences of NIS expression （X2 = 8.207, P = 0.017） and β2-MG expression （X2 = 10.121, P = 0.006） between different pathological types of thyroid carcinoma, but there was no correlation between the positive rate of the two research groups （r = -0.546, P = 0.633）. The significant differences was observed in expression of sodium/iodide symporter （X2 = 9.272, P=0.002） and expression of β2-MG （X2 = 4.441, P = 0.035） between the group with neck lymph node metastasis and the group without neck lymph node metastasis and both positive rate was significantly negatively correlated （r = -1.000, P = 0.000）. The significant differences was observed in expression of sodium/iodide symporter （X2 = 9.272, P = 0.002） and expression of β2-MG （X2 = 3.867, P = 0.043） between the group with distant organ metastasis and the group without distant organ metastasis （X2 = 11.985, P = 0.001） and both positive rate was significantly negatively correlated （r = -1.000, P = 0.000）. Conclusion： There are significantly negatively correlated between neck lymph node metastasis, distant organ metastasis and expression of sodium/iodide symporter and expression of β2-MG. Thyroid cancer lymph node and distant organ metastasis, the tumor tissue NIS expression and serum levels of β2-MG is significantly negatively correlated. The detection of serum β2-MG provides clinical reference value for the effects on radionuclide therapy and prognosis assessment of thyroid carcinoma. Serum β2-MG levels is negatively correlated with prognosis in thyroid cancer patients.

Human sodium/iodide symporter gene induced iodine uptake in human lung adenocarcinoma via baculovirus

To investigate human sodium/iodide symporter (hNIS) induced iodine uptake in human lung adenocarcinoma via baculovirus, a recombinant baculovirus encoding hNIS gene was constructed under the control of CMV promoter (Bac-CMV-hNIS). In vitro, baculovirus infected A549 cells accumulated about 27 times more 125I than that of noninfected cells. The 125I uptake was maximal after 30-min incubation of the cells, and efflux of the radioactivity was rapid, with 50% lost during the first 2 min after 125I-containing medium had been replaced by nonradioactive medium. Competition experiments in the presence of sodium perchlorate revealed a dose-dependent decrease of 125I uptake. Bac-CMV-hNIS infected tumor cells were selectively killed by exposure to 131I, as revealed by clonogenic assays. In nude mice, Bac-CMV-hNIS infected A549 cells accumulated more 131I than that of the control monitored by 1-h scintigraphy after 131I administration. The transduction of hNIS gene through baculovirus is sufficient to induce iodine transporting in A549 cells in vitro and in vivo, outlining the potential of this novel tumor gene imaging approach. But a rapid efflux of radioactivity from the tumor was shown in vivo and the in vivo therapy test showed no sign of effect.

Effects of BRAF^(V600E) Mutation on Na^+/I^- Symporter Expression in Papillary Thyroid Carcinoma

Radioiodine ablation（RIA） therapy is one of the most important treatments for papillary thyroid carcinoma（PTC）, but some patients who received 131 I have radioiodine-refractory disease caused by the decreased expression of the Na^＋/I^- symporter（NIS）. BRAF^V600E mutation is one possible risk factor that can disturb the NIS expression, but the roles are unclear in clinical practice. This research discussed the association of BRAF^V600E mutation and NIS expression in PTC tissue and the clinical implications in RIA therapy. 134 PTC samples were collected between June 2013 and June 2014 from Tongji Hospital affiliated to Tongji Medical College, and their clinical characteristics were analyzed. RT-PCR was used to detect the BRAF^V600E mutation from formalin-fixed paraffin-embedded samples, and immunohistochemistry was applied to detect the NIS expression. IPP software was used to calculate the relative expression quantity of NIS. We found that there was no significant correlation between the absorbance（A） values of NIS and clinicopathologic features in these cases, even thyroid stimulating hormone. BRAF^V600E mutation showed inhibitory effect on the NIS expression without statistically significant difference in all PTC cases（β=–0.0195, P=0.085）, but in the subgroup without hashimoto＇s thyroiditis（HT）, BRAF^V600E mutation could significantly inhibit the NIS expression（β=–0.0257, P=0.046）. The results indicate that BRAF^V600E mutation is correlated with a lower expression of NIS in PTCs without HT, suggesting the radioiodine-refractory effects during RIA therapy in these patients.

电针对紫杉醇诱导大鼠神经病理性疼痛的影响

目的观察电针(EA)对紫杉醇诱导神经病理性疼痛大鼠脊髓背角NKCC1、KCC2表达和小胶质细胞活化的影响及其可能机制。方法将48只雄性SD大鼠随机分为溶媒组(Vehicle组)、紫杉醇组(PTX组)、紫杉醇+电针组(PTX+EA组)、紫杉醇+假电针组(PTX+Sham EA组),每组12只。采用腹腔注射PTX的方法建立PTX诱导的神经病理性疼痛大鼠动物模型,建模完成后,PTX+EA组给予“足三里”、“阳陵泉”电针刺激,连续7 d。于紫杉醇注射前2 d和注射后第1、3、5、7、14、21天进行机械撤足阈值和热缩足潜伏期痛行为学测试。利用免疫荧光染色技术和Western blot技术检测脊髓背角组织中钠钾氯联合转运蛋白1(NKCC1)、钾氯联合转运蛋白2(KCC2)和小胶质细胞标志物离子钙结合衔接分子1(Iba1)表达的变化。结果与Vehicle组比较,PTX组大鼠出现双后足机械和热痛觉过敏,脊髓背角组织中NKCC1表达升高和活化的小胶质细胞数增加。与PTX组比较,PTX+EA组大鼠在第14、21天的机械和热痛觉过敏得到显著改善,脊髓背角组织中NKCC1和Iba1表达量降低,4组间KCC2表达差异无统计学意义。结论电针可有效缓解紫杉醇诱导的神经病理性疼痛,其机制可能与抑制大鼠脊髓背角组织中NKCC1表达和小胶质细胞活化有关。

钠碘同向转运体表达与功能调控的研究进展

钠碘同向转运体(sodium iodine symporter)广泛分布于人体各个器官,是器官转运I-的结构和功能基础。钠碘同向转运体主要表达在细胞的基底侧膜上,为各种生命活动提供所需的I-。目前已知,钠碘同向转运体的调控机制涉及激素、细胞因子、转录因子及信号分子的作用。此外,钠碘同向转运体作为甲状腺癌的重要治疗靶点逐渐受到关注,然而在治疗过程中唾液腺等其他器官吸收放射性碘而产生的并发症也值得重视。本文重点综述了钠碘同向转运体的表达、作用及其调控机制的研究进展,旨在为临床干预钠碘同向转运体异常相关疾病进程提供新思路。

甲状腺癌碘-131治疗抵抗发生的分子机制研究进展

甲状腺癌是内分泌系统最常见的恶性肿瘤,其中分化型甲状腺癌(differentiated thyroid carcinoma,DTC)占90%以上。多数DTC患者经过系统治疗后预后良好,但少数患者肿瘤原发灶或转移灶出现失分化现象,进展为放射性碘难治性DTC(radioiodine-refractory DTC,RAIR-DTC),预后明显变差,是甲状腺癌致死的主要原因。钠碘转运体(sodium iodide symporter,NIS)的表达和功能异常,是导致甲状腺癌碘-131治疗抵抗的主要原因,其发生受遗传学改变、表观遗传学改变、肿瘤微环境作用、自噬作用等多因素影响。遗传学改变如BRAF基因的V600E位点突变、RET/PTC基因重排等导致致癌信号通路的激活,直接或间接地影响NIS的表达及其在细胞膜上的正常定位。表观遗传学调控特定基因的表达模式,调节NIS的表达水平,进而影响甲状腺细胞的碘摄取功能。肿瘤微环境中的免疫细胞、细胞因子和细胞外基质等成分也可能通过降低NIS的表达水平和/或干扰其在细胞膜上的正常功能导致细胞碘摄取障碍。此外,自噬作为一种细胞内部的代谢调节机制,也可以调节NIS的表达及其在细胞内的分布,从而影响碘的摄取和碘-131治疗的敏感性。通过综述以上因素在甲状腺癌失分化中的作用机制,可以更全面地理解RAIR-DTC的发生和发展过程,有助于探寻新的治疗靶点,改善预后,并为患者提供更有效的个体化治疗策略。

SGLT-2抑制剂对糖尿病小鼠血管内皮细胞的影响

【目的】探讨钠-葡萄糖协同转运蛋白2(SGLT-2)抑制剂对糖尿病小白鼠血管内皮细胞的影响。【方法】将24只SPF级8周龄雄性ICR小白鼠腹腔注射低剂量链脲佐菌素(STZ)(50 mg/kg),建立糖尿病模型,造模成功,随机分为模型组和治疗组(达格列净治疗12周),6只小白鼠作为对照组,皮下注射生理盐水。三组均普通饲料喂养,动态观察每周小鼠体重、血糖的变化,比较三组小白鼠血浆肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、单核细胞趋化因子-1(MCP-1)、超氧化物歧化酶(SOD)、丙二醛(MDA)水平。【结果】第2周末至第12周末,模型组、治疗组体重均低于对照组,治疗组体重均高于模型组,差异有统计学意义(P<0.05)。与对照组比较,模型组、治疗组血糖显著升高,差异有统计学意义(P<0.05);与模型组比较,3周末至12周末,治疗组小白鼠血糖水平显著下降,差异有统计学意义(P<0.05)。模型组血浆TNF-α、IL-1β、MCP-1水平显著高于对照组,治疗组血浆TNF-α、IL-1β、MCP-1水平显著低于模型组,差异有统计学意义(P<0.05)。模型组血浆SOD水平低于对照组,治疗组血浆SOD水平高于模型组,差异有统计学意义(P<0.05);与对照组比较,模型组血浆MAD水平高于对照组,治疗组血浆MAD水平低于模型组,差异有统计学意义(P<0.05)。【结论】SGLT-2抑制剂能有效抑制糖尿病小鼠血管内皮细胞炎症因子的释放,改善血管内皮细胞功能。

高碘摄入对大鼠乳腺和胎盘钠碘转运体mRNA表达的影响

目的研究不同高碘水平饮食对孕期母鼠胎盘和哺乳期母鼠乳腺钠-碘转运体(Na+-I-symporter,NIS)mRNA水平表达的影响。方法将断乳后1个月的健康Wistar大鼠按体重随机分为适碘组(NI)、10倍碘(10HI)组、100倍碘(100HI)组,每组30只,雌∶雄比例为2∶1,其碘摄入量估计分别为6.15、61.5、615.0μg/d。染毒3个月后,采用过硫酸铵消化-砷铈催化分光光度法测定母鼠尿碘含量,分别在母鼠孕期第17天和母鼠哺乳期第10天,用反转录-聚合酶链式反应(RT-PCR)测定母鼠胎盘、乳腺钠-碘转运体(NIS)mRNA水平表达强度。结果10HI组、100HI组尿碘含量中位数分别为3597.5、25404.3μg/L,高于NI组(344.7μg/L),差异均有统计学意义(P<0.05);且尿碘中位数随着饮食中碘含量的增加而增加。与NI组比较,100HI组孕期胎盘中NIS mRNA的AR值和10HI组和100HI组哺乳期乳腺中NISmRNA的AR值均较低,经LSD检验,差异均有统计学意义(P<0.01);且AR值随着摄入碘量的增加而降低。结论高碘摄入抑制胎盘和乳腺中NIS的表达,此机制对子代有着重要的保护作用。

携带人NIS基因的重组腺病毒的构建

利用RT-PCR技术从Graves甲亢病人的甲状腺组织中扩增得到甲状腺钠/碘同向转运体(NIS)可编码区片段,并克隆到T载体,测序后亚克隆到腺病毒载体穿梭质粒pAdTrack-CMV上,再与含有骨架质粒pAdEasy-1的大肠杆菌BJ5183同源重组,经293细胞包装并扩增得到重组腺病毒AdNIS。结果显示重组腺病毒质粒经PmeI酶切鉴定,电泳中出现了诊断性片段;感染的293细胞出现了明显的细胞病变效应;PCR产物电泳证实了重组病毒的存在。病毒滴度为2.5～3×109efu/ml。表明成功构建了携带人NIS基因的重组腺病毒,这为基因转移NIS介导131I治疗非甲状腺肿瘤提供实验研究基础。

hNIS转基因介导^(131)碘对鼻咽癌细胞增殖和凋亡的影响

目的:克隆人的甲状腺钠/碘同向转运体(hNIS)基因,研究其转导在鼻咽癌细胞内的功能,以及131碘对鼻咽癌细胞增殖和凋亡的影响。方法:利用逆转录和聚合酶链反应(RT-PCR)从毒性弥漫性甲状腺肿(Graves病)病人的甲状腺组织中扩增得到hNIS的可编码区基因,并克隆到pcDNA3.1(+)-FLAG载体,获得重组真核表达质粒pcDNA3.1(+)-hNIS-FLAG。采用脂质体转染的方法,将pcDNA3.1(+)-hNIS-FLAG质粒导入到鼻咽癌细胞株CNE2,G418筛选得到稳定表达hNIS鼻咽癌细胞系CNE2-hNIS,体外培养条件下检测其对放射性碘的摄取和外流情况。CCK8试剂盒检测131碘对鼻咽癌细胞增殖的作用,AnnexinⅤ-FITC/PI双标记流式细胞技术(FCM)检测131碘作用后鼻咽癌细胞凋亡情况。结果:成功克隆hNIS基因,并建立能稳定表达hNIS的鼻咽癌细胞系CNE2-hNIS。CNE2-hNIS对125碘的吸收量比CNE2高约15倍,但在无碘的环境中,细胞内滞留的碘外流迅速,有效半衰期约8min。131碘在72 h后对CNE2-hNIS的增殖产生抑制作用,细胞早期凋亡率增加,并随着131碘浓度的增加,作用逐渐增强(P<0.01)。结论:从Graves病人的甲状腺组织中克隆的hNIS基因转染鼻咽癌细胞后,能使鼻咽癌细胞发挥高水平吸碘功能,131碘能够抑制转染hNIS的鼻咽癌细胞的增殖,促进细胞凋亡。

碘对大鼠体内及体外甲状腺钠碘转运体mRNA表达的调节

目的探讨碘过量对体内、体外甲状腺钠碘转运体(NIS)mRNA表达的影响。方法Wistar大鼠,随机分为低碘组(LI)、适碘组(NI)、5倍高碘组(5HI)、10倍高碘组(10HI)、50倍高碘组(50HI)、100倍高碘组(100HI),检测尿碘、甲状腺NISmRNA表达水平。FRTL细胞分别在含有10-6～10-3mol/L碘化钾的培养基中培养24、48h,检测NISmRNA水平的变化。结果LI组尿碘显著低于NI组,而甲状腺NISmRNA表达水平明显高于NI组(P<0.01);各高碘组尿碘与NI组比较呈成倍升高,NISmRNA水平与NI组相比逐渐下降。FRTL细胞在分别含有10-6～10-3mol/L碘化钾的培养基中培养24、48h,NISmRNA的表达水平与对照组差异无统计学意义(P>0.05)。结论碘对体内、体外甲状腺NISmRNA表达的影响存在不同的机制,长期、慢性处于高碘摄入的大鼠主要通过转录水平影响甲状腺NISmRNA的表达,而体外急性实验表明,高碘则可能通过转录后水平而起作用。

维甲酸诱导甲状腺癌细胞摄碘的实验研究

目的 探讨全反式维甲酸(ATRA)诱导甲状腺癌细胞系的钠碘同向转运体(NIS)表达及其碘摄取。方法 通过ATRA诱导甲状腺癌细胞系滤泡状甲状腺癌细胞株(FTC 133)、乳头状甲状腺癌细胞株(W3)及未分化甲状腺癌细胞株( 85 0 5C)后,经逆转录 聚合酶链反应(RT PCR)及Westernblot检测甲状腺癌细胞系的NISmRNA及其蛋白质表达,并测定甲状腺癌细胞系诱导后的摄碘变化。结果 ATRA诱导甲状腺癌细胞系4 8h后,FTC 133和W3的NISmRNA及蛋白质表达增高,85 0 5C未见变化;ATRA诱导甲状腺癌细胞系2周后,FTC 133和W3的摄碘增高。结论 ATRA能诱导分化型甲状腺癌细胞摄碘增高。

钠碘转运体与甲状腺疾病

钠碘转运体 (NIS)为甲状腺滤泡上皮细胞基底膜上的一类膜蛋白 ,主要作用是促进甲状腺逆浓度梯度转运无机碘 ,NIS受促甲状腺激素、碘、多种细胞因子及其他一些激素的调节。 NIS与自身免疫性疾病、先天性甲状腺功能低下、甲状腺肿瘤的发生密切相关 。