Faculté de Médecine, Laboratoire de Pathologie Cellulaire et Moléculaire en Nutrition, INSERM U724, Centre de Ressources Biologiques, CHU de Nancy, 54505 Vandoeuvre-Lès-Nancy, France.
BMC Cancer. 2009 Dec 4;9:423. doi: 10.1186/1471-2407-9-423.
Retinoid Receptors are involved in development and cell homeostasis. Alterations of their expressions have been observed in lung cancer. However, retinoid chemoprevention trials in populations at risk to develop such tumors have failed. Therefore, the pertinence of new clinical trials using second generation retinoid requires prior better understanding of retinoid signalling. This is our aim when validating extensively research tools, focused on Retinoic Acid Receptor beta, whose major role in lung cancer is documented.
Biocomputing was used to assess the genomic organization of RAR beta. Its putative RAR-beta1' promoter features were investigated experimentally. Specific measures realized, with qRT-PCR Syber Green assays and a triplex of Taqman probes, were extensively validated to establish Retinoid Receptors mRNAs reference values for in vivo normal human bronchial cells, lung tumors and cell lines. Finally, a pan-RAR-beta antibody was generated and extensively validated by western-blot and immunoprecipitation.
No promoter-like activity was found for RAR-beta1'. RAR-beta2 mRNAs increase signs the normal differentiation of the human bronchial epithelium while a decrease is observed in most lung cancer cell lines. Accordingly, it is also, along with RXR beta, down-regulated in lung tumors. When using nuclear extracts of BEAS-2B and normal lung cells, only the RAR-beta2 long protein isoform was recognized by our antibody.
Rigorous samples processing and extensive biocomputing, were the key factors for this study. mRNA reference values and validated tools can now be used to advance researches on retinoid signalling in the lung.
视黄酸受体参与发育和细胞内稳态。在肺癌中观察到它们的表达改变。然而，在有发展此类肿瘤风险的人群中进行的视黄酸化学预防试验已经失败。因此，使用第二代视黄酸进行新的临床试验的相关性需要事先更好地了解视黄酸信号。当广泛验证研究工具时，我们旨在验证视黄酸受体β，其在肺癌中的主要作用已有文献记载。
生物计算用于评估 RARβ的基因组组织。实验研究了其假定的 RAR-β1'启动子特征。通过 qRT-PCR Syber Green 测定和 Taqman 探针三聚体实现的特定措施进行了广泛验证，以建立体内正常人类支气管细胞、肺癌肿瘤和细胞系的视黄酸受体 mRNAs 参考值。最后，生成了一种泛 RAR-β 抗体，并通过 Western blot 和免疫沉淀进行了广泛验证。
未发现 RAR-β1'的启动子样活性。RAR-β2 mRNAs 的增加标志着人类支气管上皮的正常分化，而大多数肺癌细胞系中则减少。因此，它也与 RXRβ一起在肺癌肿瘤中下调。当使用 BEAS-2B 和正常肺细胞的核提取物时，只有 RAR-β2 长蛋白异构体被我们的抗体识别。
严格的样本处理和广泛的生物计算是本研究的关键因素。mRNA 参考值和经过验证的工具现在可以用于推进肺内视黄酸信号的研究。
