Expression of neurophysin-related precursor in cell membranes of a small-cell lung carcinoma.
Expression of neurophysin-related precursor in cell membranes of a small-cell lung carcinoma.
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小细胞肺癌细胞膜中神经素相关前体的表达。
DOI：
10.1073/pnas.87.24.9928
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发表时间：
1990
影响因子：
11.1
通讯作者：
Nilaver,G
中科院分区：
文献类型：
--
作者：
Rosenbaum,LC;Neuwelt,EA;VanTol,HH;Loh,YP;Verbalis,JG;Hellström,I;Hellström,KE;Nilaver,G
一种针对小细胞肺癌表面抗原的单克隆抗体（mAb L6）识别下丘脑核中抗利尿激素-神经physin和催产素-神经physin的共同表位。我们现在报道在人肺癌（LX-1）细胞膜中发现一种神经磷脂样前体。溶解膜的mAb L6免疫亲和层析产生约45 kDa的单条带。Western blot分析显示，该条带与抗抗利尿加压素单抗L6和抗利尿加压素前体pre -pressophysin抗体具有免疫反应性。该条带的N端测序结果表明，该条带与人促垂体前素的N端有21个氨基酸同源性，并且肿瘤抗原中的Cys33残基被Arg33取代。在细胞质提取物和培养基中对上述抗体缺乏免疫反应性表明未分泌加工过的或完整的促红细胞生成素样肽。Northern分析显示，LX-1 mRNA在大鼠前加压素C端有一个30-mer的条带，大约有1000个碱基对，比下丘脑信息大250个碱基对。用相同探针对LX-1荷瘤裸鼠脑进行原位杂交，发现在大鼠下丘脑和异种移植肿瘤中存在特异性杂交。这些发现表明，在这种肿瘤细胞系中，一种促垂体素样蛋白的表达优先针对细胞膜。
A monoclonal antibody (mAb L6) to a small-cell lung carcinoma surface antigen recognizes a common epitope of vasopressin-neurophysin and oxytocin-neurophysin in hypothalamic nuclei. We now report on the identification of a neurophysin-like precursor in human lung carcinoma (LX-1) cell membrane. mAb L6 immunoaffinity chromatography of solubilized membranes resulted in a single band of approximately 45 kDa. Western blot analysis demonstrated immunoreactivity of this band with mAb L6, anti-vasopressin, and an antibody to the vasopressin precursor, pro-pressophysin. N-terminal sequencing of this band demonstrated a 21-amino acid homology with the N terminus of human pro-pressophysin, and substitution of a Cys33 residue in the tumor antigen with Arg33. Absence of immunoreactivity with the antibodies described above in cytosolic extracts and culture medium suggests nonsecretion of processed or intact pro-pressophysin-like peptide. Northern analysis of LX-1 mRNA with a 30-mer to the C terminus of rat pro-pressophysin resulted in a band of approximately 1000 base pairs, 250 base pairs larger than hypothalamic message. In situ hybridization of LX-1 tumor-bearing nude rat brain with the same probe demonstrated specific hybridization in rat hypothalamus and xenografted tumor. These findings suggest expression of a pro-pressophysin-like protein in this tumor cell line that is preferentially targeted to the cell membrane.