Cancer Biology Division, School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT), Deemed to be University, Campus-11, Patia, Bhubaneswar- 751024, Odisha, India.
Cancer Biology Division, School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT), Deemed to be University, Campus-11, Patia, Bhubaneswar- 751024, Odisha, India.
Eur J Pharmacol. 2020 Sep 15;883:173308. doi: 10.1016/j.ejphar.2020.173308. Epub 2020 Jun 27.
NECTIN-4 [a poliovirus receptor-related-4 (PVRL-4) encoded gene] has vital roles in cancer proliferation, metastasis and angiogenesis. It possesses three different domains and it is predicted that they have different roles in cancer but the structure-function relationship is still unknown and hence carrying out a detailed study to elucidate the domain-specific functions of NECTIN-4 in cancer is necessary. Using 5-Fluouracil-resistant cervical cancer stem cells (PEMT-5FU-R-MC) and different NECTIN-4 domain-specific constructs, different domains of NECTIN-4 were over-expressed in PEMT-5FU-R-MC cells. Biochemical assays like comet, γ-H2AX immunofluorescence, western blot, in vitro tube formation, gelatin zymography, in ovo CAM assay, etc. were used to delineate the function of each domain of NECTIN-4 in cancer and their regulation by nano-formulated quinacrine (NQC). Endo-domain (lacking extracellular region corresponding to aa 30-347) and ecto-domain (lacking signal peptide and cytoplasmic region corresponding to aa 1-29 and 348-509, respectively) of NECTIN-4 were largely overexpressed in nucleus and cytoplasm, respectively. Endo-domain translocates into nucleus by physically interacting with IMPORTIN-α2, activates the DNA repair and enhances cell growth, whereas ecto-domain specifically activates angiogenesis by modulating representative angiogenic markers, inducing in vitro tube formation and in ovo blood vessel formation. Full-length NECTIN-4 (aa 1-509) was overexpressed in both nucleus and cytoplasm and modulated both DNA repair and angiogenesis. NQC down-regulated these phenomena by modulating the endo-domain and ecto-domain of NECTIN-4. Thus, current study suggested that endo-domain of NECTIN-4 translocated into nucleus and increased the DNA repair and ecto-domain of NECTIN-4 enhanced the angiogenesis, whereas NQC inhibits these processes.
NECTIN-4（一种与脊髓灰质炎病毒受体相关的 4 型基因，PVRL-4）在癌症的增殖、转移和血管生成中具有重要作用。它具有三个不同的结构域，据预测它们在癌症中具有不同的作用，但结构与功能的关系尚不清楚，因此有必要进行详细的研究来阐明 NECTIN-4 在癌症中的特定结构域功能。使用氟尿嘧啶耐药型宫颈癌干细胞（PEMT-5FU-R-MC）和不同的 NECTIN-4 结构域特异性构建体，在 PEMT-5FU-R-MC 细胞中过表达不同的 NECTIN-4 结构域。使用生物化学分析，如彗星实验、γ-H2AX 免疫荧光、western blot、体外管形成、明胶酶谱分析、鸡胚绒毛尿囊膜（CAM） assay 等，来描绘 NECTIN-4 的每个结构域在癌症中的功能及其受纳米制剂奎纳克林（NQC）的调控。NECTIN-4 的内结构域（缺少对应于 aa 30-347 的细胞外区域）和外结构域（分别缺少信号肽和对应于 aa 1-29 和 348-509 的细胞质区域）主要在细胞核和细胞质中过度表达。内结构域通过与 IMPORTIN-α2 相互作用而转位入核，激活 DNA 修复并增强细胞生长，而外结构域通过调节代表性的血管生成标志物特异性地激活血管生成，诱导体外管形成和鸡胚血管形成。全长 NECTIN-4（aa 1-509）在细胞核和细胞质中均过度表达，并调节 DNA 修复和血管生成。NQC 通过调节 NECTIN-4 的内结构域和外结构域下调了这些现象。因此，本研究表明，NECTIN-4 的内结构域转位入核，增加了 DNA 修复，而 NECTIN-4 的外结构域增强了血管生成，而 NQC 抑制了这些过程。
