Jeyachristy Sam Annie, Nazem Eshan Rosly, Thevendran Ramesh, Goyal Ahsas, Goyal Kavita, Maheswaran Solayappan, Pramanik Atreyi, Gupta Gaurav, Fuloria Neeraj Kumar, Fuloria Shivkanya, Hussain Md Sadique
Faculty of Medicine, AIMST University, 08100, Semeling, Kedah, Malaysia.
Faculty of Medicine, Royal College of Medicine Perak, Universiti Kuala Lumpur (UniKL RCMP), Ipoh, 30450, Perak, Malaysia.
Biotechnol Lett. 2025 Aug 12;47(5):90. doi: 10.1007/s10529-025-03630-3.
Acute myeloid leukemia (AML) is a neoplastic disorder of the myeloid stem cell and is most commonly diagnosed in children and young adults. N-CoR is an essential protein that regulates transcriptional repression in normal myeloid cell development Mutations or loss of function in the N-CoR gene result in the abnormal expression of critical genes involved in cell proliferation, contributing to leukemogenic transformation and the development of malignancy in acute myeloid leukemia subtype M5 (AML-M5). This study was aimed to elucidate the mechanism of N-CoR degradation by O-sialo-glycoprotein endopeptidase (OSGEP), a protease that is active in AML-M5 cells only. The AML-M5-specific proteases were isolated using HPLC size exclusion chromatography and anti-N-CoR OSGEP antibodies. In vitro experiments were performed to test the degradation of recombinant N-CoR protein by OSGEP protease. The protease's identity and composition were analyzed via mass spectrometry. Study involved transfection studies using various cell lines to evaluate the subtype-specific activity of OSGEP based on N-CoR expression levels. Study findings revealed OSGEP protease to cleave N-CoR in AML-M5 cells. Mass spectrometry confirmed the identity and composition of a purified, functionally active form of the OSGEP protease. The transfection studies proved that N-CoR was the only protein of the two that OSGEP protease acted on selectively in AML-M5 cells thus proving its specificity in the subtype of cells. Findings of present study suggests that OSGEP protease-mediated N-CoR degradation is an important factor in the development of AML-M5. Current study highlights N-CoR degradation by OSGEP as a key molecular event in AML-M5 and proposes the N-CoR protease as a potential diagnostic and therapeutic biomarker for this leukemia subtype.
急性髓系白血病（AML）是一种髓系干细胞的肿瘤性疾病，最常见于儿童和年轻人。N-CoR是一种在正常髓系细胞发育中调节转录抑制的重要蛋白质。N-CoR基因的突变或功能丧失会导致参与细胞增殖的关键基因异常表达，从而促成急性髓系白血病M5亚型（AML-M5）的致白血病转化和恶性肿瘤发展。本研究旨在阐明仅在AML-M5细胞中具有活性的蛋白酶O-唾液酸糖蛋白内肽酶（OSGEP）降解N-CoR的机制。使用高效液相色谱尺寸排阻色谱法和抗N-CoR OSGEP抗体分离AML-M5特异性蛋白酶。进行体外实验以测试OSGEP蛋白酶对重组N-CoR蛋白的降解作用。通过质谱分析该蛋白酶的身份和组成。研究涉及使用各种细胞系进行转染研究，以根据N-CoR表达水平评估OSGEP的亚型特异性活性。研究结果显示OSGEP蛋白酶在AML-M5细胞中切割N-CoR。质谱分析证实了纯化的、具有功能活性的OSGEP蛋白酶的身份和组成。转染研究证明，在AML-M5细胞中，N-CoR是OSGEP蛋白酶仅选择性作用的两种蛋白质之一，从而证明了其在该细胞亚型中的特异性。本研究结果表明，OSGEP蛋白酶介导的N-CoR降解是AML-M5发生发展的一个重要因素。当前研究强调OSGEP介导的N-CoR降解是AML-M5中的一个关键分子事件，并提出N-CoR蛋白酶作为该白血病亚型的潜在诊断和治疗生物标志物。
