Department of Pharmacy Practice and Science, College of Pharmacy, University of Nebraska Medical Center, 986145 Nebraska Medical Center, Omaha, NE, 68198-6145, USA.
College of Medicine, Division of Pediatrics, University of Nebraska Medical Center, Omaha, NE, USA.
BMC Cancer. 2019 Aug 27;19(1):837. doi: 10.1186/s12885-019-6033-2.
The activity of MP1, a pyrrolomycin, was studied in MYCN amplified neuroblastoma (NB) alone and combined with temsirolimus (TEM).
Activity of MP1 was tested in MYCN amplified (BE-2c, IMR) and non amplified (SKN-AS) NB cells. The effect of MP1 on MYCN, MCL-1, cleaved PARP, LC3II/LC3I, bcl-2, BAX, and BRD-4 were determined by western blot and RNAseq. The effect of MP1 on metabolism, mitochondrial morphology, and cell cycle was determined. Toxicology and efficacy of MP1 plus TEM were evaluated.
The IC of MP1 was 0.096 μM in BE-2c cells compared to 0.89 μM in IMR, and >50 μM in SKN-AS. The IC of MP1 plus TEM in BE-2c cells was 0.023 μM. MP1 inhibited metabolism leading to quiescence and produced a decline in cell cycle S-phase. Electron microscopy showed cristae loss and rounding up of mitochondria. Gene and protein expression for MYCN and MCL-1 declined while LCII and cleaved PARP increased. Protein expression of BAX, bcl-2, and BRD-4 were not significantly changed after MP1 treatment. The in-vivo concentrations of MP1 in blood and tumor were sufficient to produce the biologic effects seen in-vitro. MP1 plus TEM produced a complete response in 3 out of 5 tumor bearing mice. In a second mouse study, the combination of MP1 and TEM slowed tumor growth compared to control.
MP1 has a potent inhibitory effect on the viability of MYCN amplified NB. Inhibition of metabolism by MP1 induced quiescence and autophagy with a favorable toxicology and drug distribution profile. When combined with TEM anti-tumor activity was potentiated in-vitro and in-vivo.
吡咯霉素 MP1 的活性在 MYCN 扩增神经母细胞瘤（NB）中进行了研究，单独使用以及与替西罗莫司（TEM）联合使用。
在 MYCN 扩增（BE-2c、IMR）和非扩增（SKN-AS）NB 细胞中测试了 MP1 的活性。通过 Western blot 和 RNAseq 确定 MP1 对 MYCN、MCL-1、裂解 PARP、LC3II/LC3I、bcl-2、BAX 和 BRD-4 的影响。测定 MP1 对代谢、线粒体形态和细胞周期的影响。评估 MP1 加 TEM 的毒性和疗效。
MP1 在 BE-2c 细胞中的 IC 为 0.096 μM，而在 IMR 中的 IC 为 0.89 μM，在 SKN-AS 中的 IC 大于 50 μM。MP1 加 TEM 在 BE-2c 细胞中的 IC 为 0.023 μM。MP1 抑制代谢导致静止，并导致细胞周期 S 期减少。电子显微镜显示嵴丢失和线粒体圆化。MYCN 和 MCL-1 的基因和蛋白表达下降，而 LCII 和裂解 PARP 增加。MP1 处理后，BAX、bcl-2 和 BRD-4 的蛋白表达没有明显变化。血液和肿瘤中的 MP1 浓度足以产生体外观察到的生物学效应。MP1 加 TEM 在 5 只荷瘤小鼠中有 3 只产生完全反应。在第二项小鼠研究中，与对照组相比，MP1 和 TEM 的联合使用减缓了肿瘤生长。
MP1 对 MYCN 扩增 NB 的活力具有很强的抑制作用。MP1 抑制代谢诱导静止和自噬，具有良好的毒理学和药物分布特征。当与 TEM 联合使用时，在体外和体内均增强了抗肿瘤活性。
