Lunec J, Pieron C, Sherbet G V, Thody A J
Cancer Research Unit, Medical School, University of Newcastle-upon-Tyne, UK.
Pathobiology. 1990;58(4):193-7. doi: 10.1159/000163583.
Using a radioimmunoassay specific for alpha-melanocyte-stimulating hormone (alpha-MSH), significant levels of immunoreactivity were detected in a range of murine and human melanoma cell lines, including a series of ras-transfected melanocytes. The levels found in the melanoma cell lines tested varied, and overall were higher than in non-melanoma cell lines assayed for comparison. Furthermore the highest levels of immunoreactivity measured tended to be in the least differentiated and most metastatic melanoma lines. High performance liquid chromatography showed a peak of immunoreactivity which co-migrated with a desacetyl alpha-MSH standard. Additional unidentified components of immunoreactivity were found, including a high molecular weight form revealed by Sephadex-G50 gel exclusion. These may represent bound alpha-MSH or fragments of the proopiomelanocortin precursor having in common the C-terminus epitope recognised by the antibody. In view of the known effects of alpha-MSH on anchorage independent growth and metastasis of melanoma cells, our findings raise the possibility that MSH peptides may have an autocrine role in the growth and progression of melanoma. However, further characterisation of the immunoreactive species is required to determine whether these represent biologically active forms.
使用针对α-黑素细胞刺激素（α-MSH）的放射免疫测定法，在一系列小鼠和人类黑色素瘤细胞系中检测到显著水平的免疫反应性，包括一系列经ras转染的黑素细胞。所测试的黑色素瘤细胞系中的水平各不相同，总体上高于用于比较的非黑色素瘤细胞系。此外，所测量的最高免疫反应性水平往往出现在分化程度最低和转移性最强的黑色素瘤细胞系中。高效液相色谱显示免疫反应性峰值与去乙酰化α-MSH标准品共迁移。还发现了其他未鉴定的免疫反应性成分，包括通过Sephadex-G50凝胶排阻法揭示的高分子量形式。这些可能代表结合的α-MSH或阿片促黑素皮质素原前体的片段，它们具有共同的被抗体识别的C末端表位。鉴于α-MSH对黑色素瘤细胞的锚定非依赖性生长和转移的已知作用，我们的发现增加了MSH肽可能在黑色素瘤的生长和进展中具有自分泌作用的可能性。然而，需要对免疫反应性物种进行进一步表征，以确定这些是否代表生物活性形式。
