Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 06351, South Korea.
Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 06351, South Korea; Division of Hematology and Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, South Korea.
Antiviral Res. 2021 May;189:105063. doi: 10.1016/j.antiviral.2021.105063. Epub 2021 Mar 16.
Romidepsin, a histone deacetylase (HDAC) inhibitor, has been approved for the treatment of relapsed and refractory peripheral T-cell lymphoma. However the use of romidepsin reportedly causes potent EBV (Epstein-Barr virus) reactivation leading to severe adverse events in patients with natural killer (NK)/T-cell lymphoma (NKTL). As inhibition of EBV lytic cycle reactivation may help prevent romidepsin-induced adverse events in NKTL, we herein set out to identify a safe and effective drug for inhibiting EBV reactivation and examine its mechanism of inhibition. EBV reactivation was evaluated by qRT-PCR of BZLF1 and BRLF1 mRNA expression, qPCR of EBV DNA, and immunoblotting of viral EA-D protein. High-throughput screening of FDA-approved drugs was performed to identify safe and effective molecules and test their effect on romidepsin-induced EBV reactivation in the EBV-positive NKTL cell lines, SNK6 and NK92MI. We found that phosphodiesterase 5 (PDE5) inhibitors, including sildenafil (Viagra; Pfizer), appeared to be nontoxic and effective inhibitors of romidepsin-induced EBV reactivation. Clinical relevance was investigated by qPCR of EBV in two primary effusion samples of NKTL patients. We also investigated the molecular consequences downstream of sildenafil-induced PDE5 inhibition in NKTL cells. A negative correlation was established between the cGMP/PKG pathway and EBV reactivation in NKTL cells. On a molecular level, PDE5 inhibition downregulates BZLF1 and BRLF1 through cGMP/PKG signaling-induced ZNF overexpression. Co-treatment with romidepsin and sildenafil (inhibiting HDAC and PDE5, respectively) showed a synergistic inhibitory effect on NKTL cells, highlighting PDE5 as an attractive target for future therapy in NKTL.
罗米地辛是一种组蛋白去乙酰化酶（HDAC）抑制剂，已被批准用于治疗复发性和难治性外周 T 细胞淋巴瘤。然而，据报道，罗米地辛的使用会导致强烈的 EBV（Epstein-Barr 病毒）再激活，从而导致自然杀伤（NK）/T 细胞淋巴瘤（NKTL）患者出现严重的不良事件。由于抑制 EBV 裂解周期再激活可能有助于预防 NKTL 中罗米地辛诱导的不良事件，因此我们旨在确定一种安全有效的药物来抑制 EBV 再激活，并研究其抑制机制。通过 BZLF1 和 BRLF1 mRNA 表达的 qRT-PCR、EBV DNA 的 qPCR 和病毒 EA-D 蛋白的免疫印迹评估 EBV 再激活。对 FDA 批准的药物进行高通量筛选，以确定安全有效的分子，并测试它们对 EBV 阳性 NKTL 细胞系 SNK6 和 NK92MI 中罗米地辛诱导的 EBV 再激活的影响。我们发现磷酸二酯酶 5（PDE5）抑制剂，包括西地那非（伟哥；辉瑞），似乎是非毒性的，并且是罗米地辛诱导的 EBV 再激活的有效抑制剂。通过对两名 NKTL 患者的原发性渗出液样本中的 EBV 进行 qPCR 检测，研究了其临床相关性。我们还研究了西地那非诱导的 NKTL 细胞中 PDE5 抑制的下游分子后果。建立了 NKTL 细胞中 cGMP/PKG 途径与 EBV 再激活之间的负相关关系。在分子水平上，PDE5 抑制通过 cGMP/PKG 信号诱导 ZNF 过表达来下调 BZLF1 和 BRLF1。罗米地辛和西地那非（分别抑制 HDAC 和 PDE5）联合治疗对 NKTL 细胞显示出协同抑制作用，突出了 PDE5 作为 NKTL 未来治疗的有吸引力的靶点。
