非鳞状表型的鼻咽癌可能是 EGFR/PI3K/AKT/mTOR 通路抑制后的鼻咽鳞状细胞癌的一种变异型。
Nasopharyngeal carcinoma with non-squamous phenotype may be a variant of nasopharyngeal squamous cell carcinoma after inhibition of EGFR/PI3K/AKT/mTOR pathway.
机构信息
Department of Pathology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
出版信息
Histol Histopathol. 2024 May;39(5):647-657. doi: 10.14670/HH-18-673. Epub 2023 Nov 8.
Nasopharyngeal carcinoma (NPC) is a cancerous tumor that develops in the nasopharynx epithelium and typically has squamous differentiation. The squamous phenotype is evident in immunohistochemistry, with diffuse nuclear positivity for p63 and p40. Nonetheless, a few NPCs have been identified by clinicopathological diagnosis that do not exhibit the squamous phenotype; these NPCs are currently referred to as non-squamous immunophenotype nasopharyngeal carcinomas (NSNPCs). In a previous work, we have revealed similarities between the histological appearance, etiology, and gene alterations of NSNPC and conventional NPC. According to ultrastructural findings, NSNPC still falls under the category of non-keratinized squamous cell carcinoma that is undifferentiated. NSNPC has an excellent prognosis and a low level of malignancy, according to a retrospective investigation. Based on prior research, we investigated the molecular mechanism of NSNPC not expressing the squamous phenotype and its biological behavior. IHC was used to determine the expression of EGFR, PI3K, AKT, p-AKT, mTOR, p-mTOR, Notch, STAT3 and p-STAT3 in a total of 20 NSNPC tissue samples and 20 classic NPC tissue samples. We obtained human NPC cell lines (CNE-2,5-8F) and used EGFR overexpression plasmid and shRNAs to transfect them. To find out whether mRNA and proteins were expressed in the cells, we used Western blotting and qRT-PCR. Cell biological behavior was discovered using the CCK-8 assay, cell migration assay, and cell invasion assay. EGFR, PI3K, p-AKT and p-mTOR proteins were lowly expressed in NSNPC tissues by immunohistochemistry, compared with classical NPC. In the classical NPC cell lines CNE-2 and 5-8F, overexpression EGFR can up-regulate the expression of p63 through the PI3K/AKT/mTOR pathway, and promote the proliferation, migration, and invasion of nasopharyngeal carcinoma cells. At the same time, knockout of EGFR can down-regulate p63 expression through the PI3K/AKT/mTOR pathway, and inhibit the proliferation, migration, and invasion of nasopharyngeal carcinoma cells. The lack of p63 expression in NSNPC was linked with the inhibition of the EGFR/PI3K/AKT/mTOR pathway, and NSNPC may be a variant of classical NPC.
鼻咽癌(NPC)是一种发生在鼻咽部上皮的癌性肿瘤,通常具有鳞状分化。免疫组织化学显示,p63 和 p40 弥漫核阳性,具有鳞状表型。然而,一些通过临床病理诊断的 NPC 没有表现出鳞状表型;这些 NPC 目前被称为非鳞状免疫表型鼻咽癌(NSNPC)。在之前的一项工作中,我们揭示了 NSNPC 的组织学表现、病因和基因改变与传统 NPC 之间的相似性。根据超微结构发现,NSNPC 仍属于未分化的非角化鳞状细胞癌。根据回顾性研究,NSNPC 预后良好,恶性程度低。基于之前的研究,我们研究了 NSNPC 不表达鳞状表型的分子机制及其生物学行为。我们使用免疫组织化学法检测了 20 例 NSNPC 组织样本和 20 例经典 NPC 组织样本中 EGFR、PI3K、AKT、p-AKT、mTOR、p-mTOR、Notch、STAT3 和 p-STAT3 的表达。我们获得了人 NPC 细胞系(CNE-2、5-8F),并使用 EGFR 过表达质粒和 shRNA 进行转染。为了确定细胞中是否表达了 mRNA 和蛋白质,我们使用 Western blot 和 qRT-PCR。通过 CCK-8 测定、细胞迁移测定和细胞侵袭测定发现了细胞的生物学行为。免疫组织化学显示,与经典 NPC 相比,NSNPC 组织中 EGFR、PI3K、p-AKT 和 p-mTOR 蛋白表达水平较低。在经典 NPC 细胞系 CNE-2 和 5-8F 中,过表达 EGFR 可通过 PI3K/AKT/mTOR 通路上调 p63 的表达,并促进鼻咽癌细胞的增殖、迁移和侵袭。同时,敲除 EGFR 可通过 PI3K/AKT/mTOR 通路下调 p63 的表达,抑制鼻咽癌细胞的增殖、迁移和侵袭。NSNPC 中 p63 表达缺失与 EGFR/PI3K/AKT/mTOR 通路的抑制有关,NSNPC 可能是经典 NPC 的一种变异型。