Department of Preventive Veterinary Medicine, Faculty of Veterinary Medicine, Udayana University. Jl. P.B. Sudirman, Denpasar-Bali. 80234. Indonesia.
Department of Clinical Microbiology, Faculty of Medicine, Udayana University. Jl. P.B.Sudirman, Denpasar-Bali. 80234. Indonesia.
Asian Pac J Cancer Prev. 2022 Oct 1;23(10):3247-3252. doi: 10.31557/APJCP.2022.23.10.3247.
The low general toxicity against tumors expressing globotriaosylceramide (Gb3) and Shiga-like toxins produced by E. coli have been proposed as an anti-cancer therapy because of their specific target. This study aimed to determine the potency of the local strains of E. coli O157:H7 isolated from humans and cattle as a new breast cancer therapy by analyzing the cell cycle's inhibition and apoptosis induction.
Approximately 10 cultured T47D cells were subjected to Shiga-like toxin produced by four local isolates of E. coli O157:H7, including KL-48 (2) from humans, and SM-25 (1), SM-7 (1), DS-21 (4) from cattle. Using ATCC 43894 as a control, the treatment was observed for 24 h by two replications. In addition, a FITC-Annexin V and PI assay were used to observe apoptosis and necrosis effect, as well as to analyze the cell cycle using propidium iodide (PI) staining.
The results showed the toxicity effect of Shiga in the human T47 D cells line. The viability of the cells is subjected to Shiga-like toxins produced by KL-48 (2), SM7 (1), ATCC 43894, SM-25 (1), and DS-21 (4) isolates decreased with 15.20, 16.36, 22.17, 22.64, and 33.86%, in contrary to control of 94.36%. These were supported by the cells entering the late apoptosis of the cell cycle through each isolate with 67.66, 62.60, 63.68, 63.90, and 54.74%, and a control of 0.01%. Also, the necrosis cell for each treatment of 12.73, 19.3, 10.84, 10.53, and 4.86% was higher than the control of 5.51%. These were confirmed by the higher percentage of the cells treated with toxins of KL-48 (2), SM7(1), ATCC 43894, SM-25 (1), and DS-21 (4), which entered G0-G1 of the cell cycle phase with 66.41, 63.37, 61.52, 55.36, and 47.28%, respectively, than control of 40.69%. Additionally, the toxicity effect was supported by an increase in the cells entering the S and the G2-M phase of the cycle for each treatment.
It is concluded that the Shiga-like toxin produced by E. coli O157:H7 local isolates can be developed as a drug against breast cancer based on its effect to arrest induction of the cell cycle and inducing apoptosis.
由于其特定的靶点，针对表达神经节苷脂（Gb3）和大肠杆菌产生的志贺样毒素的肿瘤具有较低的一般毒性，因此被提议作为一种抗癌疗法。本研究旨在通过分析细胞周期的抑制和凋亡诱导，确定从人和牛分离出的大肠杆菌 O157:H7 的本地株作为新的乳腺癌治疗方法的效力。
用来自人类的 KL-48（2）和来自牛的 SM-25（1）、SM-7（1）、DS-21（4）等四种本地分离的大肠杆菌 O157:H7 的志贺样毒素处理大约 10 个培养的 T47D 细胞。以 ATCC 43894 作为对照，在 24 小时内进行两次重复处理。此外，使用 FITC-Annexin V 和 PI 检测来观察凋亡和坏死效应，并使用碘化丙啶（PI）染色来分析细胞周期。
结果显示，人类 T47D 细胞系中存在 Shiga 的毒性作用。KL-48（2）、SM7（1）、ATCC 43894、SM-25（1）和 DS-21（4）分离株产生的志贺样毒素使细胞活力降低，分别为 15.20%、16.36%、22.17%、22.64%和 33.86%，而对照为 94.36%。这些结果通过每个分离株将细胞进入晚期细胞凋亡的细胞周期得到支持，凋亡率分别为 67.66%、62.60%、63.68%、63.90%和 54.74%，而对照为 0.01%。此外，每个处理的坏死细胞为 12.73%、19.3%、10.84%、10.53%和 4.86%，高于对照的 5.51%。这些结果通过 KL-48（2）、SM7（1）、ATCC 43894、SM-25（1）和 DS-21（4）处理的细胞进入细胞周期 G0-G1 期的百分比更高得到证实，分别为 66.41%、63.37%、61.52%、55.36%和 47.28%，而对照为 40.69%。此外，每个处理的细胞进入 S 和 G2-M 周期阶段的数量增加，这也支持了毒性作用。
综上所述，大肠杆菌 O157:H7 本地分离株产生的志贺样毒素可以作为治疗乳腺癌的药物开发，因为它具有抑制细胞周期诱导和诱导细胞凋亡的作用。
