Erickson Lori A, Letts Gary A, Shah Sonali M, Shackelton Jeffrey B, Duncan Lyn M
Dermatopathology Unit, Pathology Service, Massachusetts General Hospital and Harvard Medical School, Boston, MA 2114, USA.
Mod Pathol. 2009 Jul;22(7):969-76. doi: 10.1038/modpathol.2009.56. Epub 2009 Apr 24.
The transient receptor potential cation channel, subfamily M, member 1 (TRPM1/Melastatin-1/MLSN-1) expression has been shown to have prognostic utility in the evaluation of primary cutaneous melanoma. We analyzed a series of spindled and epithelioid cell nevi (Spitz) and primary cutaneous nodular melanomas to determine whether the expression of TRPM1 mRNA may be useful in distinguishing between Spitz nevi and nodular melanomas and to further examine the patterns of TRPM1 mRNA expression in cutaneous melanocytic proliferations. Formalin-fixed, paraffin-embedded tissues from 95 Spitz nevi and 33 nodular melanomas were analyzed for the expression of TRPM1 mRNA by in situ hybridization using (35)S-labeled riboprobes. Ubiquitous melanocytic expression of TRPM1 mRNA was observed in 56 of 95 (59%) Spitz nevi and 4 of 33 (12%) nodular melanomas. Diffusely scattered loss of TRPM1 mRNA was identified in 38 of 95 (40%) Spitz nevi and 2 of 33 (6%) nodular melanomas. Regional loss of the TRPM1 mRNA expression by a significant subset of dermal tumor cells or a complete absence of TRPM1 expression by the dermal tumor was identified in 27 of 33 (82%) nodular melanomas, but only 1 of 95 (1%) Spitz nevi. These findings suggest that the pattern of TRPM1 mRNA expression may be helpful in the differentiation of Spitz nevi and nodular melanomas. Of the 16 patients who experienced metastasis, 15 (94%) had primary tumors that displayed reduced MLSN mRNA expression by all or a part of the dermal tumor.
瞬时受体电位阳离子通道M亚家族成员1（TRPM1/褪黑素-1/MLSN-1）的表达已被证明在原发性皮肤黑色素瘤的评估中具有预后价值。我们分析了一系列梭形和上皮样细胞痣（Spitz痣）及原发性皮肤结节性黑色素瘤，以确定TRPM1 mRNA的表达是否有助于区分Spitz痣和结节性黑色素瘤，并进一步研究TRPM1 mRNA在皮肤黑素细胞增殖中的表达模式。使用（35）S标记的核糖探针，通过原位杂交分析95例Spitz痣和33例结节性黑色素瘤的福尔马林固定石蜡包埋组织中TRPM1 mRNA的表达。在95例Spitz痣中的56例（59%）和33例结节性黑色素瘤中的4例（12%）观察到TRPM1 mRNA在黑素细胞中普遍表达。在95例Spitz痣中的38例（40%）和33例结节性黑色素瘤中的2例（6%）发现TRPM1 mRNA呈弥漫性散在缺失。在33例结节性黑色素瘤中的27例（82%）中，真皮肿瘤细胞的一个重要亚群出现TRPM1 mRNA表达区域性缺失或真皮肿瘤完全不表达TRPM1，但在95例Spitz痣中仅1例（1%）出现这种情况。这些发现表明，TRPM1 mRNA的表达模式可能有助于区分Spitz痣和结节性黑色素瘤。在16例发生转移的患者中，15例（94%）的原发性肿瘤全部或部分真皮肿瘤显示MLSN mRNA表达降低。
