Pasquali D, Bellastella A, Valente A, Botti G, Capasso I, del Vecchio S, Salvatore M, Colantuoni V, Sinisi A A
Istituto di Endocrinologia, Facoltá di Medicina, Seconda Universitá di Napoli, Naples, Italy.
Eur J Endocrinol. 1997 Oct;137(4):410-4. doi: 10.1530/eje.0.1370410.
Retinoids seem to act as agents of chemoprevention and differentiation in breast diseases. Their action is mediated by nuclear receptors, retinoic acid receptors (RAR alpha, RAR beta, RAR gamma) and retinoid X receptors (RXR alpha, RXR beta, RXR gamma) and modulated by cellular retinol binding proteins (CRBP). There are few published data on CRBP expression. In this study, we evaluated the expression of RAR alpha, beta and gamma and CRBP type I (CRBP-I) gene expression in fibrocystic disease (FD) and in breast cancer (BC), studying 14 FD and 20 BC surgical samples by reverse transcription (RT)-PCR. We also evaluated mRNA concentrations in cancer samples by a semiquantitative PCR method, co-amplifying RAR alpha, RAR beta and CRBP-I genes with an unrelated gene, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), as internal control. All benign and malignant breat tissues expressed RAR alpha, beta and gamma, and CRBP-I mRNAs. A greater concentration of RAR beta mRNA was detected in cancer tissues with lower oestrogen and progesterone receptor concentrations, whereas RAR alpha was detected in variable concentrations that were not related to those of steroid receptors. The CRBP-I concentration was similar in all samples studied. We demonstrated that all three RARs and CRBP-I transcripts are expressed in FD, and that RAR beta, RAR gamma and CRBP-I mRNAs also are present in BC tissues. This indicates that both malignant and benign breast tissues may be target for retinoids, justifying the use of natural and synthetic vitamin A derivatives in the chemoprevention of breast disease.
类视黄醇似乎在乳腺疾病中充当化学预防和分化的介质。它们的作用由核受体、维甲酸受体（RARα、RARβ、RARγ）和类视黄醇X受体（RXRα、RXRβ、RXRγ）介导，并受细胞视黄醇结合蛋白（CRBP）调节。关于CRBP表达的已发表数据很少。在本研究中，我们通过逆转录（RT）-PCR研究了14例纤维囊性疾病（FD）和20例乳腺癌（BC）手术样本，评估了RARα、β和γ以及I型CRBP（CRBP-I）基因在纤维囊性疾病和乳腺癌中的表达。我们还通过半定量PCR方法评估了癌症样本中的mRNA浓度，将RARα、RARβ和CRBP-I基因与无关基因甘油醛-3-磷酸脱氢酶（GAPDH）共同扩增作为内对照。所有良性和恶性乳腺组织均表达RARα、β和γ以及CRBP-I mRNA。在雌激素和孕激素受体浓度较低的癌症组织中检测到更高浓度的RARβ mRNA，而检测到的RARα浓度各不相同，与类固醇受体的浓度无关。在所有研究样本中，CRBP-I浓度相似。我们证明，所有三种RAR和CRBP-I转录本在FD中均有表达，并且RARβ、RARγ和CRBP-I mRNA也存在于BC组织中。这表明恶性和良性乳腺组织都可能是类视黄醇的作用靶点，这为在乳腺疾病化学预防中使用天然和合成维生素A衍生物提供了依据。
