Neurofibromatosis type 1 associated plexiform neurofibroma (pNF) is characterized by abundant fibroblasts and dense collagen, yet the intricate interactions between tumor-origin cells (Schwann cells) and neurofibroma-associated fibroblasts (NFAFs) remain elusive. Employing single-cell RNA sequencing on human pNF samples, we generated a comprehensive transcriptomics dataset and conducted cell-cell communication analysis to unravel the molecular dynamics between Schwann cells and NFAFs. Our focus centered on the pleiotrophin (PTN)/nucleolin (NCL) axis as a pivotal ligand-receptor pair orchestrating this interaction. Validation of PTN involvement was affirmed through coculture models and recombinant protein experiments. Functional and mechanistic investigations, employing assays such as CCK8, EdU, Western Blot, ELISA, Hydroxyproline Assay, and Human phospho-kinase array, provided critical insights. We employed siRNA or inhibitors to intercept the PTN/NCL/proline-rich Akt substrate of 40 kDa (PRAS40) axis, validating the associated molecular mechanism. Our analysis highlighted a subset of Schwann cells closely linked to collagen deposition, underscoring their significance in pNF development. The PTN/NCL axis emerged as a key mediator of the Schwann cell-NFAF interaction. Furthermore, our study demonstrated that elevated PTN levels enhanced NFAF proliferation and collagen synthesis, either independently or synergistically with TGF-β1 in vitro. Activation of the downstream molecule PRAS40 was noted in NFAFs upon PTN treatment. Crucially, by targeting NCL and PRAS40, we successfully reversed collagen synthesis within NFAFs. In conclusion, our findings unveil the pivotal role of the PTN/NCL/PRAS40 axis in driving pNF development by promoting NFAFs proliferation and function. Targeting this pathway emerges as a potential therapeutic strategy for pNF. This study contributes novel insights into the molecular mechanisms governing pNF pathogenesis.

1 型神经纤维瘤病相关丛状神经纤维瘤 (pNF) 的特点是丰富的成纤维细胞和致密的胶原蛋白，但肿瘤起源细胞（施万细胞）和神经纤维瘤相关成纤维细胞 (NFAF) 之间复杂的相互作用仍然难以捉摸。通过对人类 pNF 样本进行单细胞 RNA 测序，我们生成了全面的转录组数据集，并进行了细胞间通讯分析，以揭示施万细胞和 NFAF 之间的分子动力学。我们的重点集中在多效蛋白 (PTN)/核仁素 (NCL) 轴上，作为协调这种相互作用的关键配体-受体对。通过共培养模型和重组蛋白实验证实了 PTN 参与的验证。采用 CCK8、EdU、蛋白质印迹、ELISA、羟脯氨酸测定和人磷酸激酶阵列等测定法进行的功能和机制研究提供了重要的见解。我们采用 siRNA 或抑制剂来拦截 40 kDa (PRAS40) 轴的 PTN/NCL/富含脯氨酸的 Akt 底物，验证相关的分子机制。我们的分析强调了与胶原蛋白沉积密切相关的雪旺细胞子集，强调了它们在 pNF 发展中的重要性。 PTN/NCL 轴成为施万细胞-NFAF 相互作用的关键介质。此外，我们的研究表明，体外 PTN 水平升高可以独立或与 TGF-β1 协同作用，增强 NFAF 增殖和胶原蛋白合成。 PTN 处理后 NFAF 中下游分子 PRAS40 被激活。至关重要的是，通过靶向 NCL 和 PRAS40，我们成功逆转了 NFAF 内的胶原蛋白合成。总之，我们的研究结果揭示了 PTN/NCL/PRAS40 轴通过促进 NFAF 增殖和功能来驱动 pNF 发展的关键作用。针对这一途径成为 pNF 的潜在治疗策略。这项研究为控制 pNF 发病机制的分子机制提供了新的见解。