Li B, Wang H, Chen Z
International Co-operative Laboratory for Signal Transduction, Second Military Medical University, Shanghai.
Zhonghua Zhong Liu Za Zhi. 1998 Sep;20(5):345-7.
To investigate the association between signal-regulatory protein alpha (SIRP alpha) and hepatocellular carcinoma (HCC).
Thirty-six pairs of HCC and the surrounding noncancerous hepatic tissues, one normal liver cell line and 4 HCC cell lines were used to extract the total RNA and then to prepare the mRNA. The expression of SIRP alpha was determined by Northern blot analysis. The results were analyzed in association with the pathologic characteristics of each sample.
SIRP alpha expressed at low level in 20 of 36 HCC samples and 2 of 4 HCC cell lines. Of the two major hybridization signals, a 3.9 kb transcript in HCC samples was 2-4 times lower than that in the surrounding noncancerous hepatic tissues, whereas a 2.5 kb transcript was 4-6 times as low. Furthermore, a hybridization signal slightly longer than 3.9 kb, being absent in the surrounding noncancerous hepatic tissue, appeared in 9 of the 20 HCC samples. Low level expression of SIRP alpha was observed in all of the 5 HCC samples that had intrahepatic or portal metastasis.
The expression of SIRP alpha, especially 2.5 kb transcript, was down-regulated in HCC, and an unknown mumber or a variant of SIRP family existed in some tumor tissues. SIRP alpha protein may play an important role in hepatic oncogenesis and metastasis of HCC.
研究信号调节蛋白α（SIRPα）与肝细胞癌（HCC）之间的关联。
采用36对HCC及其周围非癌肝组织、1种正常肝细胞系和4种HCC细胞系提取总RNA，进而制备mRNA。通过Northern印迹分析确定SIRPα的表达。结合每个样本的病理特征对结果进行分析。
36个HCC样本中的20个以及4个HCC细胞系中的2个SIRPα表达水平较低。在两个主要杂交信号中，HCC样本中3.9 kb转录本比周围非癌肝组织低2 - 4倍，而2.5 kb转录本低4 - 6倍。此外，20个HCC样本中的9个出现了一个略长于3.9 kb的杂交信号，该信号在周围非癌肝组织中不存在。在所有5个发生肝内或门静脉转移的HCC样本中均观察到SIRPα低水平表达。
HCC中SIRPα的表达，尤其是2.5 kb转录本的表达下调，并且在一些肿瘤组织中存在未知数量或SIRP家族变体。SIRPα蛋白可能在HCC的肝脏肿瘤发生和转移中起重要作用。
