<p>Identification of Apolipoprotein E as a Potential Diagnostic Biomarker of Nasopharyngeal Carcinoma</p>

Abstract

Purpose: Apo-E, a secreted protein, is closely related to the migration and invasion of tumor cells. In this study, we aimed to analyze the expression of Apo-E in nasopharyngeal carcinoma (NPC) patients and cell lines, as well as its effects on NPC cell behavior. Patients and Methods: Our study included 35 patients with NPC from Zhongnan Hospital. Expression levels of Apo-E in patients with NPC were examined by quantitative reverse transcription-polymerase chain reaction, Western blot, and immunohistochemical (IHC) staining. Receiver operating characteristic (ROC) curves were analyzed using the SPSS 22 software to estimate the sensitivity and specificity of the Apo-E protein in diagnosing NPC. Additionally, the level of Apo-E in NPC cell lines (NP69, 6-10B, and 5-8F) was investigated by Western blotting and IHC. Results: Levels of Apo-E were higher in NPC patients than in controls. Moreover, ROC analysis revealed that increased Apo-E in the serum of NPC patients may act as a potential biomarker for NPC diagnosis (Area under the curve 0.917). Furthermore, similar results were also identified in NPC cancer cell lines. RNA interference technology was used to overexpress the endogenous Apo-E in the NPC cell line 6-10B. Wound healing and transwell assays indicated that the overexpression of Apo-E increased the number of cell colonies and migration ability, respectively. Conclusion: In this study, we found that Apo-E was elevated in NPC patients and may act as a potential biomarker for NPC diagnosis. In addition, Apo-E was upregulated in NPC cell lines and promoted cell growth, migration, and invasion.

The Role of ApoE Serum Levels and ApoE Gene Polymorphisms in Patients with Laryngeal Squamous Cell Carcinoma

“…Xue et al investigated the links between ApoE and nasopharyngeal carcinoma. According to that study, patients with nasopharyngeal carcinoma had a statistically significant increase in serum ApoE levels along with statistically significantly ( p < 0.05) more common metastases to the lymph nodes and invasion of surrounding tissues [ 34 ]. These findings are in concordance with Jaykar et al’s statement that reducing the amount of ApoE reduces the invasion of tumor cells into healthy tissues by minimizing matrix degradation and the number of invadopodia [ 56 ].…”

“…Not only is ApoE a potential biomarker for lung cancer, but it has also been reported to be one of the biomarkers to help diagnose breast cancer in men [ 33 ]. ApoE is associated with an increased risk of developing various cancers, including the nasopharynx [ 18 , 32 , 33 , 34 ]. However, the interactions between ApoE and LSCC have not been adequately explored.…”