PO.MCB11.01 · 分子与细胞生物学
评估胆碱乙酰转移酶(ChAT)在T细胞恶性肿瘤中的作用
Evaluating the role of choline acetyltransferase (ChAT) in T cell malignancies
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
乙酰胆碱(ACh)是一种经典的神经递质,其免疫调节作用日益受到认识。除神经组织外,活化的T细胞表达胆碱乙酰转移酶(ChAT),从而实现ACh的局部合成和释放,ACh通过烟碱型和毒蕈碱型受体调节活化、细胞因子产生和血管张力。虽然这条通路可减轻炎症并维持免疫稳态,但其在恶性T细胞内的功能仍知之甚少。PTEN缺失是侵袭性T细胞恶性肿瘤的标志,它组成性地激活PI3K-Akt通路以促进不受控制的生长和存活。我们假设肿瘤内在的ChAT约束这些Akt依赖性应激反应,充当恶性进展的内在制动器。利用条件性T细胞PTEN缺陷小鼠模型,我们发现ChAT在与PI3K-Akt过度激活相吻合的特定胸腺细胞发育阶段上调,并且在癌前PTEN缺陷背景下,ChAT阳性胸腺细胞与ChAT阴性细胞相比表现出更高的活化标志物表达和更活化的发育表型。在PTEN缺失背景下ChAT的缺失进一步增加pAkt水平并改变早期活化标志物,这与向致癌应激增强的转变相一致。在功能上,在该模型中删除T细胞特异性ChAT以等位基因剂量依赖的方式缩短了淋巴瘤生存期,表明内源性胆碱能活性对肿瘤侵袭性提供了可测量的约束。总之,这些发现支持一种模型,即胆碱能信号与T细胞恶性肿瘤中的致癌性PI3K-Akt活性相交汇。本项目将界定这种相互作用在细胞、分子和治疗上的相关性,总体目标是鉴定胆碱能通路作为改变PTEN缺陷型T细胞癌症中肿瘤演化的新切入点。
查看英文原文 English abstract
Acetylcholine (ACh) is a classical neurotransmitter increasingly recognized for its immunoregulatory roles. Beyond neural tissues, activated T cells express choline acetyltransferase (ChAT), enabling the local synthesis and release of ACh, which acts through nicotinic and muscarinic receptors to modulate activation, cytokine production, and vascular tone. While this pathway can dampen inflammation and sustain immune homeostasis, its function within malignant T cells remains poorly understood. PTEN loss, a hallmark of aggressive T cell malignancies, constitutively activates the PI3K-Akt pathway to promote unchecked growth and survival. We hypothesized that tumour-intrinsic ChAT restrains these Akt-dependent stress responses, serving as an intrinsic brake on malignant progression. Using a conditional T cell PTEN-deficient mouse model, we found that ChAT is upregulated at specific thymocyte developmental stages that coincide with PI3K Akt hyperactivation, and that ChAT-positive thymocytes in the pre-malignant PTEN-deficient setting display higher activation marker expression and a more activated developmental phenotype compared to ChAT-negative cells. Loss of ChAT in the PTEN-null background further increases pAkt levels and alters early activation markers, which is consistent with a shift toward heightened oncogenic stress. Functionally, deleting T cell-specific ChAT in this model shortens lymphoma survival in an allele dosage-dependent manner, indicating that endogenous cholinergic activity provides a measurable constraint on tumour aggressiveness. Together, these findings support a model in which cholinergic signalling intersects with oncogenic PI3K Akt activity in T cell malignancy. This proposal will define the cellular, molecular, and therapeutic relevance of this interaction, with the overall goal of identifying cholinergic pathways as new entry points for modifying tumour evolution in PTEN-deficient T cell cancers.
利益披露 Disclosure
A. Hilal, None..
M. A. Cox, None.