N-羟乙酰神经氨酸(Neu5Gc)参与肿瘤进程的研究进展

Advances in involvement of Neu5Gc in tumor progression

大多数哺乳动物体内均含有Neu5Ac和Neu5Gc这两种形式的唾液酸。在人体内,由于胞苷单磷酸N-乙酰神经氨酸羟化酶CMAH的缺失,无法内源性合成Neu5Gc,来自外源性饮食的Neu5Gc及其复合物被机体吸收并沉积在细胞表面。Neu5Gc在体内参与细胞凋亡、细胞信号转导及诱导体内产生抗Neu5Gc抗体进而诱导机体产生慢性炎症最终导致肿瘤的发生和发展。这为激活Neu5Gc相关的致癌途径提供了分子基础和Neu5Gc相关糖基化表位,这类特征分子可被用来靶向肿瘤细胞,或者在肿瘤部位分泌或脱落到体液中作为非侵入性肿瘤生物标志物。本文综述唾液酸家族中的Neu5Gc引起的炎症反应和肿瘤进程中的变化情况及其相应病理生理学功能,为临床肿瘤鉴别诊断和治疗提出指导。

Most mammals contain two forms of sialic acid,Neu5 Ac and Neu5 Gc.In the human body,due to the absence of cytidine monophosphate N-acetylneuraminic acid hydroxylase CMAH,endogenous Neu5 Gc cannot be synthesized.Neu5 Gc and its complexes from the exogenous diet are absorbed by the body and deposited on cell surfaces.Neu5 Gc participates in cell apoptosis,cell signal transduction and induces the production of anti-Neu5 Gc antibodies in the body and then induces the body to produce chronic inflammation.As a result it promotes the occurrence and development of tumors.This intricate interaction provides a molecular basis for activating Neu5 Gc-related oncogene pathways,and also provides an important source of Neu5 Gc-related glycosylation epitopes.These type of molecules can be used to target tumor cells,or glycoproteins secreted or shed into body fluids at tumor sites can be used as noninvasive tumor biomarkers.This study reviewed the changes in inflammatory response and tumor progression caused by Neu5 Gc in the sialic acid family and their corresponding pathological and physiological functions,which will be guiding significance for clinical differential diagnosis and specific immunotherapy of tumors.