Blom D J, Mooy C M, Luyten G P, Kerkvliet S, Ouwerkerk I, Zwinderman A H, Schrier P I, Jager M J
Department of Ophthalmology, Leiden University Hospital, The Netherlands.
J Pathol. 1997 Jan;181(1):75-9. doi: 10.1002/(SICI)1096-9896(199701)181:1<75::AID-PATH724>3.0.CO;2-V.
HLA class I is expressed in 75-85 per cent of uveal melanoma and cytoplasmic c-myc expression has been reported in 78 per cent of uveal melanoma. In skin melanoma, an inverse relationship has been observed between HLA class I expression and c-myc. The purpose of this study was to determine whether a similar correlation occurred between high expression of c-myc and low expression of HLA class I in uveal melanoma. The expression of c-myc, HLA-A, and HLA-B was determined by immunohistochemistry on formalin-fixed and paraffin-embedded sections of 30 uveal melanomas. Cell cultures from four primary uveal melanomas (lines 92-1, MEL 202, OCM-1, and EOM-3) and one uveal melanoma metastasis (line OMM-1) were tested for mRNA levels of c-myc and HLA-A and HLA-B in Northern blot assays. The high level of expression of cytoplasmic c-myc was significantly correlated with low expression of HLA-B (P = 0.03) and vice versa. High expression of HLA-B was significantly correlated with the presence of epithelioid cells (P = 0.004). The inverse correlation observed between c-myc and HLA-B expression is similar to previous observations in cutaneous melanoma. By downregulating HLA-B expression, c-myc may influence the immune response in uveal melanoma. Tumours containing epithelioid cells showed a significantly higher expression of HLA-B than tumours of the spindle cell type.
75% - 85%的葡萄膜黑色素瘤表达HLA - I类分子，据报道78%的葡萄膜黑色素瘤存在细胞质c - myc表达。在皮肤黑色素瘤中，已观察到HLA - I类分子表达与c - myc之间呈负相关。本研究的目的是确定在葡萄膜黑色素瘤中，c - myc高表达与HLA - I类分子低表达之间是否存在类似的相关性。通过免疫组织化学方法，对30例葡萄膜黑色素瘤的福尔马林固定石蜡包埋切片进行c - myc、HLA - A和HLA - B表达的检测。对来自4例原发性葡萄膜黑色素瘤（92 - 1、MEL 202、OCM - 1和EOM - 3系）和1例葡萄膜黑色素瘤转移灶（OMM - 1系）的细胞培养物进行Northern印迹分析，检测c - myc以及HLA - A和HLA - B的mRNA水平。细胞质c - myc的高表达水平与HLA - B的低表达显著相关（P = 0.03），反之亦然。HLA - B的高表达与上皮样细胞的存在显著相关（P = 0.004）。c - myc与HLA - B表达之间观察到的负相关与先前在皮肤黑色素瘤中的观察结果相似。通过下调HLA - B表达，c - myc可能会影响葡萄膜黑色素瘤中的免疫反应。含有上皮样细胞的肿瘤比梭形细胞型肿瘤显示出显著更高的HLA - B表达。
