眼黑色素瘤是成人常见的原发性恶性眼肿瘤，有效的治疗方法有限。表观遗传调控在肿瘤发生发展中发挥着重要作用。转换/蔗糖非发酵 (SWI/SNF) 染色质重塑复合物以及溴结构域和末端外结构域家族蛋白是多种癌症中涉及的表观遗传调节因子。我们的目的是筛选针对这些调节因子的候选小分子抑制剂，并研究其在眼部黑色素瘤中的作用和机制。我们观察了相应基因敲低引起的表型以及与 BRD 抑制剂治疗和 SWI/SNF 复合物敲低的协同效应。采用流式细胞术分析JQ-1对眼部黑色素瘤细胞周期和凋亡的影响。通过RNA测序，我们还探讨了BRD4的机制。虽然shBRD4和shBRD9组没有统计学上明显的变化，但BRD4抑制剂（JQ-1）的肿瘤抑制效果最好。有趣的是，shBRD4组中JQ-1的抑制作用降低。 JQ-1 抑制多种细胞系和荷瘤小鼠中黑色素瘤的生长。我们发现这 28 个常见差异表达基因中有 17 个在用 JQ-1 处理 MEL270 和 MEL290 细胞后下调。这 17 个基因中的 4 个：TP53I11、SH2D5、SEMA5A 和 MDGA1，与 BRD4 呈正相关。在TCGA数据库中，TP53I11、SH2D5、SEMA5A和MDGA1的低表达提高了患者的总体生存率。此外，TP53I11、SH2D5 和 SEMA5A 低表达组的无病生存率增加。JQ-1 可能作用于 BRD4 下游，通过诱导 G1 细胞周期停滞来抑制眼部黑色素瘤生长。

Ocular melanoma is a common primary malignant ocular tumor in adults with limited effective treatments. Epigenetic regulation plays an important role in tumor development. The switching/sucrose nonfermentation (SWI/SNF) chromatin remodeling complex and bromodomain and extraterminal domain family proteins are epigenetic regulators involved in several cancers. We aimed to screen a candidate small molecule inhibitor targeting these regulators and investigate its effect and mechanism in ocular melanoma.We observed phenotypes caused by knockdown of the corresponding gene and synergistic effects with BRD inhibitor treatment and SWI/SNF complex knockdown. The effect of JQ-1 on ocular melanoma cell cycle and apoptosis was analyzed with flow cytometry. Via RNA sequencing, we also explored the mechanism of BRD4.The best tumor inhibitory effect was observed for the BRD4 inhibitor (JQ-1), although there were no statistically obvious changes in the shBRD4 and shBRD9 groups. Interestingly, the inhibitory effect of JQ-1 was decrease in the shBRD4 group. JQ-1 inhibits the growth of melanoma in various cell lines and in tumor-bearing mice. We found 17 of these 28 common differentially expressed genes were downregulated after MEL270 and MEL290 cells treated with JQ-1. Four of these 17 genes, TP53I11, SH2D5, SEMA5A, and MDGA1, were positively correlated with BRD4. In TCGA database, low expression of TP53I11, SH2D5, SEMA5A, and MDGA1 improved the overall survival rate of patients. Furthermore, the disease-free survival rate was increased in the groups with low expression of TP53I11, SH2D5, and SEMA5A.JQ-1 may act downstream of BRD4 and suppress ocular melanoma growth by inducing G1 cell cycle arrest.