Vanoli Fabio, Herviou Laurie, Tsuda Yusuke, Sung Patricia, Xie Ziyu, Fishinevich Eve, Min Soe S, Mallen William, de Wardin Henry de Traux, Zhang Yanming, Jasin Maria, Antonescu Cristina R
Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Developmental Biology Program, Sloan Kettering Institute, New York, NY, USA.
Oncogenesis. 2023 Feb 17;12(1):8. doi: 10.1038/s41389-023-00454-6.
The discovery of neurotrophic tyrosine receptor kinase (NTRK) gene fusions as pan-tumor oncogenic drivers has led to new personalized therapies in oncology. Recent studies investigating NTRK fusions among mesenchymal neoplasms have identified several emerging soft tissue tumor entities displaying various phenotypes and clinical behaviors. Among them, tumors resembling lipofibromatosis or malignant peripheral nerve sheath tumors often harbor intra-chromosomal NTRK1 rearrangements, while most infantile fibrosarcomas are characterized by canonical ETV6::NTRK3 fusions. However, appropriate cellular models to investigate mechanisms of how kinase oncogenic activation through gene fusions drives such a wide spectrum of morphology and malignancy are lacking. Progress in genome editing has facilitated the efficient generation of chromosomal translocations in isogenic cell lines. In this study we employ various strategies to model NTRK fusions, including LMNA::NTRK1 (interstitial deletion) and ETV6::NTRK3 (reciprocal translocation) in human embryonic stem (hES) cells and mesenchymal progenitors (hES-MP). Here, we undertake various methods to model non-reciprocal, intrachromosomal deletions/translocations by induction of DNA double strand breaks (DSBs) exploiting either the repair mechanisms of homology directed repair (HDR) or non-homologous end joining (NHEJ). Expression of LMNA::NTRK1 or ETV6::NTRK3 fusions in either hES cells or hES-MP did not affect cell proliferation. However, the level of mRNA expression of the fusion transcripts was significantly upregulated in hES-MP, and phosphorylation of the LMNA::NTRK1 fusion oncoprotein was noted only in hES-MP but not in hES cells. Similarly, an NTRK1-driven transcriptional profile related to neuronal and neuroectodermal lineage was upregulated mainly in hES-MP, supporting the importance of appropriate cellular context in modeling cancer relevant aberrations. As proof of concept of the validity of our in vitro models, phosphorylation was depleted by two TRK inhibitors, Entrectinib and Larotrectinib, currently used as targeted therapy for tumors with NTRK fusions.
神经营养性酪氨酸受体激酶（NTRK）基因融合作为泛肿瘤致癌驱动因素的发现，已带来肿瘤学领域新的个性化疗法。最近对间叶性肿瘤中NTRK融合的研究已识别出几种新出现的软组织肿瘤实体，它们表现出不同的表型和临床行为。其中，类似脂肪纤维瘤病或恶性外周神经鞘瘤的肿瘤常存在染色体内NTRK1重排，而大多数婴儿纤维肉瘤的特征是典型的ETV6::NTRK3融合。然而，目前缺乏合适的细胞模型来研究激酶致癌激活通过基因融合驱动如此广泛的形态学和恶性程度的机制。基因组编辑技术的进展促进了在同基因细胞系中高效产生染色体易位。在本研究中，我们采用多种策略对NTRK融合进行建模，包括在人胚胎干细胞（hES）和间充质祖细胞（hES-MP）中构建LMNA::NTRK1（间质性缺失）和ETV6::NTRK3（相互易位）。在此，我们采用多种方法通过利用同源定向修复（HDR）或非同源末端连接（NHEJ）的修复机制诱导DNA双链断裂（DSB）来对非相互性、染色体内缺失/易位进行建模。在hES细胞或hES-MP中表达LMNA::NTRK1或ETV6::NTRK3融合并不影响细胞增殖。然而，融合转录本的mRNA表达水平在hES-MP中显著上调，并且仅在hES-MP中检测到LMNA::NTRK1融合癌蛋白的磷酸化，而在hES细胞中未检测到。同样，与神经元和神经外胚层谱系相关的NTRK1驱动的转录谱主要在hES-MP中上调，这支持了在模拟癌症相关畸变时合适细胞背景的重要性。作为我们体外模型有效性的概念验证，两种TRK抑制剂恩曲替尼和拉罗替尼可消除磷酸化，这两种抑制剂目前被用作NTRK融合肿瘤的靶向治疗药物。
