ANALYSIS OF TR3 RECEPTOR IN APOPTOSIS OF PROSTATE CANCER AND APPLICATION FOR DIAGNOSIS OF PROSTATE CANCER RECCURENCE

(1)TR 3孤儿受体在药物诱导的前列腺增生中的作用在雄激素应答性LNCaP人前列腺癌细胞中，人TR 3孤儿受体可以通过雄激素或生长因子的刺激而快速诱导（即，EGF或FGF。相反，去势后大鼠前列腺腹侧区TR 3孤儿受体基因表达增加，细胞凋亡呈梯状。这一现象促使我们进一步分析人TR 3孤儿受体在前列腺癌细胞凋亡诱导中的作用。北方印迹分析显示，在LNCaP细胞中，10 mM钙离子载体或300 mM依托泊苷（VP 16）处理后，人TR 3孤儿受体可被快速诱导。反义TR 3孤儿受体稳定的转染子LNCaP细胞表明，与对照（载体）稳定的转染子LNCaP细胞相比，需要高得多的依托泊苷浓度来显示类似的细胞凋亡。在一起， ...更多信息 提示TR 3孤儿受体可能在药物诱导前列腺癌细胞凋亡中起重要作用。(2)TR 3孤儿受体对人睫状神经营养因子受体（CNTFR）基因内含子增强子的诱导在人TR 3孤儿受体CNTFR基因α组分的第五内含子中鉴定出一种激素应答元件，CNTER-NERB（5 ′-AAAGGTCA-3 ′）。电泳迁移率变动分析表明，在体外表达的TR 3和CNTFR-NBRE之间的特异性结合。利用CAT的报告基因分析表明，CNTFR具有增强子活性，可以以剂量依赖的方式被TR 3受体诱导。在不存在CNTFR-BNBRE的情况下，这种诱导显著降低。总之，这些结果表明CNTFR-NBRE足以介导TR 3诱导CNTFR增强子活性的作用。因此，我们的发现可能表明CNTFR是TR 3调控的靶基因，并扩展了TR 3在神经系统中的作用。(3)前列腺癌组织中TR 3受体的原位杂交最近，Jenkins等显示了明确的数据，其中使用荧光原位杂交检测前列腺癌组织和转移性淋巴结中的c-myc扩增。我们在人前列腺癌、良性前列腺肥大和正常前列腺组织中的原位杂交数据显示，TR 3孤儿受体mRNA的表达模式与c-myc的表达模式非常相似。更有趣的是，TR 3孤儿受体mRNA在前列腺癌区域比在邻近的正常或良性肥大组织中更高表达。在低分化腺癌组织中表达明显。这些数据表明，TR 3孤儿受体可能在前列腺癌的发展或进展中发挥一些重要作用，与c-myc癌基因的方式相同。(4)前列腺癌组织中端粒酶活性的检测分析端粒酶活性与前列腺癌病理分化程度的关系。采用端粒重复序列扩增法（TRAP）检测端粒酶活性。结果表明，90%的前列腺癌组织端粒酶活性阳性，且原发灶和活检组织中端粒酶活性均较高，以低分化腺癌多见。RT-PCR检测hTERT基因的表达。结果显示，70%的前列腺癌组织中的表达高于正常前列腺组织。少

(1) A role of TR3 orphan receptor in drug-induced prostate apoptosisIn androgen-responsive LNCaP human prostatic cancer cells, human TR3 orphan receptor can be rapidly induced by stimulation of androgen or growth factors (i.e., EGF or FGF). In contrast, ablation of androgen by castration can also induce the expression of TR3 orphan receptor gene in rat ventral prostate which underwent programmed cell death (apoptosis) characterized by DNA fragmentation ladder. This phenomenon prompted us to further analyze the roles of human TR3 orphan receptor in apoptosis-induced prostate cancer cells. Northern blot analysis shows that human TR3 orphan receptor can be induced rapidly after treatment of 10 mM calcium ionophore or 300 mM etoposide (VP 16) in LNCaP cells. Antisense TR3 orphan receptor stable transfectant LNCaP cells indicated a much higher concentration of etoposide was needed to show the similar apoptosis as compared to the control (vector) stable transfectant LNCaP cells. Together, ou … More r data suggest that human TR3 orphan receptor may play an important role of drug-induced apoptosis in human prostate cancer cells.(2) Induction of an intronic enhancer of the human ciliary neurotrophic factor receptor (CNTFR) gene by the TR3 orphan receptorA hormone response element, CNTER-NERB (5'-AAAGGTCA-3') has been identified in the fifth intron of the alpha component of CNTFR gene for the human TR3 orphan receptor. A specific binding between in vitro expressed TR3 and CNTFR-NBRE was demonstrated by using electrophoretic mobility shift assay. A reporter gene assay using CAT showed that CNTFR has an enhancer activity that could be induced by TR3 receptor in a dose-dependent manner. This induction was significantly reduced in the absence of CNTFR-BNBRE. Together, these results indicate CNTFR-NBRE is sufficient to mediate TR3 action in inducing the enhancer activity of CNTFR. Our finding may, therefore, suggest CNTFR is a target gene regulated by TR3 and expand the role of TR3 in the nervous system.(3) In situ hybridization of TR3 receptor in prostate cancer tissues.Recently, Jenkins et al. showed clear data in which c-myc amplification in prostate cancer tissues and metastatic lymphnodes was detected using fluorescence in situ hybridization. Our in situ hybridization data in human prostate cancer, benign prostate hypertrophy, and normal prostate tissues revealed that the expression patterns of TR3 orphan receptor mRNA were very similar to those of c-myc. More interestingly, TR3 orphan receptor mRNAs were more highly expressed in prostate cancer area than in adjacent normal or benign hypertrophic tissue. Furthermore, these expressions were highly seen in poorly differentiated adenocarcinoma area. These data suggest that the TR3 orphan receptor may play some important roles in development or progression of prostate cancer in the same manner as the c-myc oncogene.(4) Telomerase activities in prostate cancer tissues.We analyzed the telomerase activity in association with the pathological differentiation of prostate cancer. Telomerase activity was examined by PCR-based telomeric repeat amplification protocol (TRAP) assay. The results showed that most of prostate cancer tissues (90%) displayed telomerase activity and high activity in primary and biopsy specimens were more frequent detected in poorly differentiated adenocarcinoma. Also, the expression of catalytic subunit, hTERT, was detected by RT-PCR. It revealed that the expression in 70% of prostate cancer tissues was more highly seen in comparison with those in normal prostate tissues. Less