Less toxic treatment strategies for testicular germ cell tumor (TGCT) patients are needed, as overtreatment is a concern due to the long-term side effects of platin-based chemotherapy. Although clinical benefit from classical hypomethylating agents has to date been limited, TGCTs show an abnormal DNA methylome indicating the potential of treating TGCTs with hypomethylating drugs. We tested, for the first time in TGCT cell lines, a new synthetic flavonoid compound (MLo1302) from the 3-nitroflavanone family of DNA methyltransferase (DNMT) inhibitors. We show that MLo1302 reduces cell viability (including of cisplatin resistant cell line NCCIT-R), with IC₅₀s (inhibitory concentration 50) within the nanomolar range for NCCIT and NTERA-2 cells, and proved its cytotoxic effect. Exposure to MLo1302 reduced DNMT protein expression, similar to decitabine, and showed a partial effect in cell differentiation, reducing protein expression of pluripotency markers. RT² profiler expression array indicated several dysregulated targets, related to activation of apoptosis, differentiation, and cell cycle arrest. We validated these data by showing increased apoptosis, increased protein expression of cleaved caspase 8 and activated caspase 2, and reduced proliferation (BrdU assay), with increase in CDKN1A and decrease in MIB-1 expression. Therefore, synthetic drugs designed to target DNA methylation in cells may uncover effective treatments for TGCT patients.

中文翻译：

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用新合成的黄酮类化合物MLo1302靶向生殖细胞肿瘤可有效降低肿瘤细胞活力并诱导凋亡和细胞周期阻滞

对于睾丸生殖细胞肿瘤（TGCT）患者，需要毒性较低的治疗策略，因为基于铂类化学疗法的长期副作用引起过度治疗。尽管迄今为止为止经典的低甲基化药物的临床获益有限，但TGCT显示出异常的DNA甲基化组，表明用低甲基化药物治疗TGCT的潜力。我们首次在TGCT细胞系中测试了一种来自DNA甲基转移酶（DNMT）抑制剂3-硝基黄烷酮家族的新型合成类黄酮化合物（MLo1302）。我们显示MLo1302可降低细胞活力（包括顺铂耐药细胞系NCCIT-R），并具有IC ₅₀在纳摩尔范围内对NCCIT和NTERA-2细胞具有抑制作用（抑制浓度50），并证明了其细胞毒性作用。与地西他滨相似，暴露于MLo1302会降低DNMT蛋白的表达，并在细胞分化中显示出部分作用，从而降低多能性标记物的蛋白表达。RT ² profiler表达阵列指示了几个失调的靶标，与细胞凋亡的激活，分化和细胞周期停滞有关。我们通过显示凋亡增加，裂解的半胱天冬酶8和活化的半胱天冬酶2的蛋白表达增加，增殖减少（BrdU分析），CDKN1A增加和MIB-1表达减少来验证这些数据。因此，旨在靶向细胞中DNA甲基化的合成药物可能会发现针对TGCT患者的有效治疗方法。