Zou Bingqing, Zhu Wenjia, Liu Hongqin, Wang Shuyi, Zhu Hongguang
Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China.
Department of Pathology, Eye & ENT Hospital, Fudan University, Shanghai, China.
Cell Physiol Biochem. 2018;49(4):1364-1379. doi: 10.1159/000493414. Epub 2018 Sep 11.
BACKGROUND/AIMS: Sinonasal mucosal melanoma (SMM) is a rare but extremely aggressive disease. Interestingly, however, as lethal as SMM, a few patients could survive for over 5 years without metastasis. However, biomarkers for metastatic SMM are lacking.
Laser-capture microdissection combined with microRNA microarray and RT-qPCR was performed in formalin-fixed paraffin-embedded tissue samples from SMM patients whose follow-up studies were carried out in parallel. In vitro cell proliferation and invasion assays, gelatin zymography, western blot analysis and RT-qPCR were performed in melanoma cell lines.
In the discovery stage, miR-4633-5p expressed differentially in sinonasal mucosal melanoma patients with short and long disease-specific survival. Subsequent large-sample validation revealed that expression of miR-4633-5p was lower in metastatic SMM than in non-metastatic patients (P< 0.001). Moreover, miR-4633-5plow was able to identify metastatic SMM with specificity of 100% (5/5) and sensitivity of 87.5% (21/24). Multivariate analysis further pinpointed miR-4633-5p as an independent marker for metastasis (relative risk: 54.22, P< 0.001). In vitro, overexpression of miR-4633-5p suppressed the growth and invasiveness of melanoma cells through inhibiting activation of Akt pathway and secretion of MMP2, while knockdown of miR-4633-5p reversed the inhibitory effects.
Our findings underpin miR-4633-5p as a predictive biomarker in metastatic SMM and a pivotal tumor suppressor that negatively regulates the invasive growth of melanoma cells. Quantitative detection of miR-4633-5p can diagnostically predict the risk of metastasis in SMM patients, which, in turn, may lead to more personalized treatment with better prognosis.
背景/目的：鼻窦黏膜黑色素瘤（SMM）是一种罕见但极具侵袭性的疾病。然而，有趣的是，尽管SMM致命，但仍有少数患者可在无转移的情况下存活超过5年。然而，目前缺乏转移性SMM的生物标志物。
对并行进行随访研究的SMM患者的福尔马林固定石蜡包埋组织样本进行激光捕获显微切割，并结合微小RNA微阵列和RT-qPCR。在黑色素瘤细胞系中进行体外细胞增殖和侵袭试验、明胶酶谱分析、蛋白质免疫印迹分析和RT-qPCR。
在发现阶段，miR-4633-5p在疾病特异性生存期短和长的鼻窦黏膜黑色素瘤患者中表达存在差异。随后的大样本验证显示，转移性SMM中miR-4633-5p的表达低于非转移性患者（P<0.001）。此外，miR-4633-5p低表达能够识别转移性SMM，特异性为100%（5/5），敏感性为87.5%（21/24）。多变量分析进一步确定miR-4633-5p是转移的独立标志物（相对风险：54.22，P<0.001）。在体外，miR-4633-5p的过表达通过抑制Akt通路的激活和MMP2的分泌来抑制黑色素瘤细胞的生长和侵袭性，而敲低miR-4633-5p则逆转了这些抑制作用。
我们的研究结果支持miR-4633-5p作为转移性SMM的预测生物标志物以及负向调节黑色素瘤细胞侵袭性生长的关键肿瘤抑制因子。对miR-4633-5p的定量检测可在诊断上预测SMM患者的转移风险，进而可能带来预后更好的更个性化治疗。
