Cockroaches live in places where various pathogens exist. Thus, they are more likely to use antimicrobial compounds to defend against pathogen intrusions. We previously performed an in silico analysis of the Periplaneta americana transcriptome and detected periplanetasin-5 using an in silico antimicrobial peptide prediction method. In this study, we investigated whether periplanetasin-5 has anticancer activity against the human leukemia cell line K562. Cell growth and survival of K562 cells treated with periplanetasin-5 were decreased in a dose-dependent manner. By using flow cytometric analysis, acridine orange/ethidium bromide (AO/EB) staining, and DNA fragmentation, we found that periplanetasin-5 induced apoptotic and necrotic cell death in leukemia cells. In addition, these events were associated with increased levels of the proapoptotic proteins Fas and cytochrome c and reduced levels of the anti-apoptotic protein Bcl-2. Periplanetasin-5 induces the cleavage of pro-caspase-9, pro-caspase-8, pro-caspase-3, and poly (ADP-ribose) polymerase (PARP). The above data suggest that periplanetasin-5 induces apoptosis via both the intrinsic and extrinsic pathways. Furthermore, caspase-related apoptosis was further confirmed by using the caspase inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]-fluoromethylketone (Z-VAD-FMK), which reversed the periplanetasin-5-induced reduction in cell viability. In conclusion, periplanetasin-5 caused apoptosis in leukemia cells, suggesting its potential utility as an anticancer therapeutic agent.

中文翻译：

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Periplanetasin-5 的抗癌活性，一种来自美洲大蠊的抗菌肽。

蟑螂生活在各种病原体存在的地方。因此，他们更有可能使用抗菌化合物来抵御病原体入侵。我们之前对美洲大蠊转录组进行了计算机分析，并使用计算机检测了 periplanetasin-5抗菌肽预测方法。在这项研究中，我们研究了 periplanetasin-5 是否对人类白血病细胞系 K562 具有抗癌活性。用 periplanetasin-5 处理的 K562 细胞的细胞生长和存活以剂量依赖性方式降低。通过使用流式细胞术分析、吖啶橙/溴化乙锭 (AO/EB) 染色和 DNA 片段化，我们发现 periplanetasin-5 在白血病细胞中诱导凋亡和坏死细胞死亡。此外，这些事件与促凋亡蛋白 Fas 和细胞色素c水平升高有关并降低抗凋亡蛋白 Bcl-2 的水平。Periplanetasin-5 诱导 pro-caspase-9、pro-caspase-8、pro-caspase-3 和聚 (ADP-核糖) 聚合酶 (PARP) 的裂解。上述数据表明，periplanetasin-5 通过内在和外在途径诱导细胞凋亡。此外，通过使用半胱天冬酶抑制剂苯甲氧基-缬氨酰-丙氨酰-天冬氨酰-[O-甲基]-氟甲基酮 (Z-VAD-FMK) 进一步证实了与半胱天冬酶相关的细胞凋亡，它逆转了 periplanetasin-5 诱导的细胞活力降低。总之，periplanetasin-5 引起白血病细胞凋亡，表明其作为抗癌治疗剂的潜在用途。