MYCN是一个重要的原癌基因，属于MYC基因家族，该家族还包括C-MYC和L-MYC等成员。MYC基因家族的共性在于它们编码的蛋白质都是转录因子，含有碱性螺旋-环-螺旋（bHLH）和亮氨酸拉链（LZ）结构域，能够与DNA结合并调控大量靶基因的表达，从而参与细胞增殖、分化、凋亡、代谢和干细胞维持等关键生物学过程。MYCN位于人类2号染色体短臂（2p24.3），其编码的蛋白质在胚胎发育中起重要作用，尤其在神经系统发育中调控神经前体细胞的增殖和分化。正常情况下，MYCN在成人组织中表达水平较低，但在多种恶性肿瘤中常出现过表达或扩增，尤其是神经母细胞瘤、小细胞肺癌和髓母细胞瘤等。MYCN的过表达会促进细胞周期进程、抑制分化、增强代谢重编程（如糖酵解）并维持肿瘤干细胞特性，从而导致肿瘤发生、进展和耐药性。相反，降低MYCN表达可诱导肿瘤细胞分化或凋亡，因此MYCN成为神经母细胞瘤等癌症的治疗靶点。MYCN的突变较少见，但其基因扩增（拷贝数增加）是神经母细胞瘤的重要预后标志，扩增患者通常预后较差。此外，MYCN与其他信号通路（如ALK、RAS/MAPK）相互作用可协同促进肿瘤发生。在非病理状态下，MYCN表达受严格调控，其异常激活可能导致发育缺陷。研究还发现，MYCN可通过调控miRNA（如let-7家族）影响肿瘤微环境。针对MYCN的治疗策略包括直接抑制其表达或功能（如BET抑制剂）、靶向其下游通路以及免疫治疗。MYCN的生物学功能复杂，既是发育调控的关键因子，也是癌症治疗的挑战性靶点。

此基因是Myc家族的成员，并且编码蛋白质与碱性螺旋 - 环 - 螺旋（bHLH）结构域。该蛋白位于细胞核内，并且必须以结合DNA与另一个的bHLH蛋白质二聚化。该基因的扩增与多种肿瘤相关的，最显着的神经母细胞瘤。已发现该基因编码不同亚型多重选择性剪接转录变异体。 [由RefSeq的，2014年6月提供]

The MYCN gene, located on the short arm of human chromosome 2 (2p24.3), encodes a critical oncoprotein that is a core member of the MYC transcription factor family, which also includes C-MYC and L-MYC. As a basic helix-loop-helix (bHLH) leucine zipper (LZ) protein, MYCN functions as a master regulator of gene expression by binding to specific DNA sequences, thereby orchestrating essential biological processes such as cell proliferation, differentiation, apoptosis, metabolic reprogramming, and stem cell maintenance. While MYCN expression is tightly restricted and generally low in adult tissues, it plays a pivotal role in embryonic development, particularly in driving the proliferation and differentiation of neural progenitor cells. In pathological contexts, MYCN is frequently amplified or overexpressed in aggressive malignancies, most notably neuroblastoma, small cell lung cancer, and medulloblastoma, where it promotes tumorigenesis by accelerating cell cycle progression, inhibiting differentiation, enhancing glycolytic metabolism, and preserving tumor stem cell properties. Although point mutations are rare, gene amplification serves as a significant adverse prognostic indicator, particularly in neuroblastoma, and often synergizes with other oncogenic signaling pathways, such as ALK and RAS/MAPK, to drive tumor progression and therapeutic resistance. Conversely, the downregulation of MYCN can induce differentiation or apoptosis, highlighting its potential as a therapeutic target; however, its essential role in normal development and its complex interactions with the tumor microenvironment, including the regulation of microRNAs like the let-7 family, present significant challenges for treatment strategies that include BET inhibitors, downstream pathway targeting, and immunotherapy.

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