Background:

Cardiac glycosides (CGs) possess a chemical structure similar to steroids, and are inhibitors of the sodium potassium pump. An anti-tumor effect of CGs in breast and prostate cancers has been reported, but the effect of CGs on ovarian cancer is still unclear.

Aims:

In this study, the effects of CGs on proliferation, cytotoxicity and cell cycle of ovarian cancer cell line (SKOV-3) have been investigated.

Procedure:

The cell proliferation and cytotoxicity were detected by MTT assay and LDH activity assay, respectively. CGs, at concentrations higher than IC50, decreased cell proliferation and showed increased cytotoxicity toward SKOV-3 cells. The colony-formation ability was reduced after treatment with digoxin and digitoxin for 10 days. Furthermore, we explored the effect of digoxin and digitoxin on the distribution of cell cycle by flow cytometry.

Results:

Results revealed that both digoxin and digitoxin led to cell cycle arrest in G₀/G₁ phase with 24 or 48 hours, but the arrest of G₀/G₁ phase was not observed at 72 hours. We evaluated the percentage of hypodiploid cell population as an index of the cellular fragments through flow cytometry. The data indicated that cellular fragments were significantly increased by treating with digitoxin at the concentrations of IC50 and 10⁻⁶ M for 72 hours.

Conclusion:

Taken together, these data suggest that CGs decreased cell proliferation and increased cytotoxicity through cell cycle arrest at the G₀/G₁ phase. CGs have anti-tumor effect in SKOV-3 cells and might be a potential therapeutic drug for ovarian cancer. Since this study is a preliminary investigation of CGs on SKOV-3 cells, more experiments might be performed in the future. Furthermore, more ovarian cancer cell lines might also be employed in the future studies to confirm the effect of CGs in ovarian cancer.

中文翻译：

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地高辛和洋地黄毒苷对人卵巢癌细胞系SKOV-3细胞生长的抑制作用

背景：

强心苷 (CG) 具有类似于类固醇的化学结构，是钠钾泵的抑制剂。已经报道了CGs在乳腺癌和前列腺癌中的抗肿瘤作用，但CGs对卵巢癌的影响仍不清楚。

目标：

在本研究中，研究了CGs对卵巢癌细胞系（SKOV-3）增殖、细胞毒性和细胞周期的影响。

程序：

MTT法和LDH活性法分别检测细胞增殖和细胞毒性。浓度高于 IC50 的 CG 会降低细胞增殖并显示对 SKOV-3 细胞的细胞毒性增加。用地高辛和地高辛处理 10 天后，集落形成能力降低。此外，我们通过流式细胞术探讨了地高辛和洋地黄毒苷对细胞周期分布的影响。

结果：

结果表明，二者地高辛和洋地黄毒苷导致细胞周期停滞在G中₀ / G _1个相用24或48小时，但G的阻滞₀ / G ₁阶段没有在72小时时观察到的。我们通过流式细胞术评估了亚二倍体细胞群的百分比作为细胞碎片的指标。数据表明，通过用IC50和10 ^-6  M浓度的洋地黄毒苷处理72小时，细胞碎片显着增加。

结论：

综上所述，这些数据表明CGs通过在G ₀ /G ₁期的细胞周期停滞来降低细胞增殖并增加细胞毒性。CGs在SKOV-3细胞中具有抗肿瘤作用，可能是一种潜在的卵巢癌治疗药物。由于这项研究是对 SKOV-3 细胞上 CG 的初步研究，未来可能会进行更多的实验。此外，在未来的研究中也可能使用更多的卵巢癌细胞系来证实 CGs 在卵巢癌中的作用。