Shao Z, Shen Z, Fontana J A
Cancer Hospital, Shanghai Medical University.
Zhonghua Zhong Liu Za Zhi. 1995 Nov;17(6):425-8.
A number of studies have shown that retinoids can inhibit malignant cell growth including certain breast carcinoma cells. Its inhibitory effect is observed only in ER positive but not in ER negative breast cancer cells. We examined retinoic acid nuclear receptors (RARs) and retinoids X receptors (RXRs) levels in 6 breast carcinoma cell lines and 18 breast cancer biopsy specimens. We found that RAR-alpha mRNA level was significantly higher in ER positive cell lines and samples. RAR-gamma mRNA was expressed at relatively high levels in majority of tumor samples independent of the ER-status while RAR-beta mRNA was expressed at low levels. We also found high RXR-alpha mRNA levels in all of the tumor samples examined while RXR-gamma mRNA could not be detected. Our study suggests a possibility that retinoids inhibit tumor cell growth through RAR-alpha and RAR-alpha levels may serve as a potential marker to determine responsiveness of patients to retinoids therapy.
多项研究表明，类视黄醇可抑制恶性细胞生长，包括某些乳腺癌细胞。其抑制作用仅在雌激素受体（ER）阳性的乳腺癌细胞中观察到，而在ER阴性的乳腺癌细胞中未观察到。我们检测了6种乳腺癌细胞系和18例乳腺癌活检标本中视黄酸核受体（RARs）和类视黄醇X受体（RXRs）的水平。我们发现，ER阳性细胞系和样本中RAR-α mRNA水平显著更高。RAR-γ mRNA在大多数肿瘤样本中表达水平相对较高，与ER状态无关，而RAR-β mRNA表达水平较低。我们还发现，在所有检测的肿瘤样本中RXR-α mRNA水平都很高，而未检测到RXR-γ mRNA。我们的研究表明，类视黄醇可能通过RAR-α抑制肿瘤细胞生长，且RAR-α水平可能作为确定患者对类视黄醇治疗反应性的潜在标志物。
