Melhem Sarah A, Saadah Loai M, Attallah Zeena S, Mansi Iman A, Hamed Saja H, Talib Wamidh H
Department of Clinical Pharmacy, Faculty of Pharmacy, Applied Science Private University. Amman, Jordan.
Department of Clinical Pharmacy and Pharmacy Practice, Faculty of Pharmaceutical Sciences, Hashemite University, Zarqa, Jordan.
Heliyon. 2024 Sep 29;10(19):e38685. doi: 10.1016/j.heliyon.2024.e38685. eCollection 2024 Oct 15.
Angiotensin-converting enzyme 2 (ACE2) is a pivotal molecular nexus linking novel coronavirus disease to breast cancer. In-silico investigations have repurposed carnosine for both these conditions based on its potential ACE2 inhibitory properties.
Utilizing an ACE2 inhibitor screening kit, we determined the inhibitory range of carnosine doses. Subsequently, we examined the effect of carnosine on ACE2 expression in supernatants from various breast cancer cell lines (MCF-7, MDA-MB-231, and EMT-6). Additionally, we compared ACE2 activity in cell line pellets with and without carnosine and a putative ACE2 activator using a fluorometric activity assay kit. Finally, we performed a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay across overlapping concentrations.
Carnosine exhibited dose-dependent ACE2 inhibition within the 100-300 mM range. ACE2 expression significantly diminished after exposure to carnosine for 2 and 24 h in MDA-MB-231 and MCF-7 cell lines, respectively. MTT assay unveiled notable antiproliferative effects in MDA-MB-231 (50 % survival at approximately 265 mM) and EMT-6 cell lines (unquantifiable 50 % survival dose). Conversely, the MCF-7 cell line displayed a modest increase in proliferation (Effective concentration 50-186 mM, ∼40 % increased survival).
This pioneering study delineates evident dose-dependent ACE2 inhibition by carnosine. Moreover, it unveils the modulatory impact of this ACE2 inhibitor in breast cancer cell lines. Carnosine demonstrated a significant antiproliferative effect on aggressive cell lines while sparing luminal cell lines from substantial toxic or proliferative effects.
血管紧张素转换酶2（ACE2）是连接新型冠状病毒病与乳腺癌的关键分子枢纽。基于肌肽潜在的ACE2抑制特性，计算机模拟研究已将其用于这两种病症的治疗。
我们使用ACE2抑制剂筛选试剂盒确定了肌肽剂量的抑制范围。随后，我们检测了肌肽对各种乳腺癌细胞系（MCF-7、MDA-MB-231和EMT-6）上清液中ACE2表达的影响。此外，我们使用荧光活性测定试剂盒比较了添加和不添加肌肽以及一种假定的ACE2激活剂的细胞系沉淀中的ACE2活性。最后，我们在重叠浓度范围内进行了3-(4,5-二甲基噻唑-2-基)-2,5-二苯基-2H-四唑溴盐（MTT）测定。
肌肽在100-300 mM范围内表现出剂量依赖性的ACE2抑制作用。在MDA-MB-231和MCF-7细胞系中，分别在暴露于肌肽2小时和24小时后，ACE2表达显著降低。MTT测定显示，在MDA-MB-231（约265 mM时50%存活）和EMT-6细胞系（50%存活剂量无法量化）中，肌肽具有显著的抗增殖作用。相反，MCF-7细胞系的增殖略有增加（半数有效浓度为50-186 mM，存活率增加约40%）。
这项开创性研究描述了肌肽对ACE2明显的剂量依赖性抑制作用。此外，它还揭示了这种ACE2抑制剂对乳腺癌细胞系的调节作用。肌肽对侵袭性细胞系具有显著的抗增殖作用，同时使管腔细胞系免受实质性的毒性或增殖影响。
