RESUMO
Objective: To investigate the association between WD40-encoding RNA antisense to p53 ( WRAP53 ß), a telomerase new core subunit, and the clinical, genomic and immune infiltration characteristics of squamous cell carcinoma of the head and neck (HNSC), and to explore for potential joint targeted therapy of HNSC. Methods: Tumor IMmune Estimation Resource (TIMER) online modules were adopted to predict the association between WRAP53 ß expression and the clinical features, oncogene, and immune infiltration of HNSC in the Cancer Genome Atlas (TCGA) cohort. Tumor Immune Single-cell Hub (TISCH) was used to analyze WRAP53 ß expression at the single cell level. Analysis of the small molecule inhibitors potentially targeting WRAP53 ß was carried out by Computational Analysis of REsistance (CARE). In the in vitro verification experiment, recombinant lentiviral particles with the sh WRAP53 ß sequence were synthesized. Then, the oral squamous cell carcinoma cell line Cal27 (the sh WRAP53 ßgroup) stably expressing sh WRAP53 ß were constructed, and two control groups were set up (the shNC group consisting of Cal27 cells added with lentiviral particles containing non-specific control sequences and the Con group consisting of untreated Cal27 cells). MTT assay was done to examine the proliferation of cells in the three groups. Cellular immunofluorescence assay was done for further qualitative examination of the expression of P53 protein in the cells of the sh WRAP53 ß group and the shNC group. Western blot was done to measure the expression of WRAP53ß and γ-H2AX, a DNA damage protein, in the 18 th, 23 rd and 28 th passages of the sh WRAP53 ß group and the shNC group. Finally, specimens of 13 cases of oral squamous cell carcinoma and 7 cases of oral mucosal inflammation were collected, and the expression of WRAP53ß and γ-H2AX in the clinical specimens of oral squamous cell carcinoma was verified with immunohistochemistry. Resluts: TIMER analysis revealed that the expression level of WRAP53 ß in HNSC tissues was significantly higher than that in normal tissues. There was a significant positive correlation between WRAP53 ß expression and multiple genes in the p53 pathway, including CCNB1, CCNB2 and CDK1. Although no significant correlation between WRAP53 ß expression and infiltrating immune cells was found, WRAP53 ß was significantly positively correlated with the inflammatory factors IFN-γ and IL23A, and negatively correlated with IL-1A and IL-6 in HPV-positive carcinoma of the head and neck. TISCH single cell sequencing datasets also showed higher expression of WRAP53 ß in malignant cells, and very low or zero expression in immune cells. According to the CARE scores, the most potent WRAP53 ß co-inhibitory drugs were ATM, CDK1 and MDM4 targeted inhibitors. In vitro cell experiments showed that the proliferation ability of Cal27 cells decreased significantly in the sh WRAP53 ß group as compared with that of the control group between Day 5 and Day 7 ( P<0.05). Furthermore, the expression of P53 decreased significantly in the sh WRAP53 ß group. As compared with the control group, the expression of WRAP53ß in sh WRAP53 ß group significantly decreased in the 18 th, 23 rd and 28 th passages ( P<0.05), while γ-H2AX expression only decreased in the 18 th and 28 th passages ( P<0.05) according to the results of Western blot. Clinical specimens showed rather high positive expression rate of γ-H2AX in oral squamous cell carcinoma tissues (12/13), while the expression of WRAP53ß was not detected in oral mucositis samples (0/7). Conclusions: WRAP53 ß showed significantly higher expression level in HSNC, and was significantly associated with p53 pathway genes. ATM, CDK1 and MDM4 inhibitors may be potential WRAP53 ß co-inhibitory agents. RNA interference of WRAP53 ß expression may cause inhibition of DNA damage, thereby indicating therapeutic potential for HNSC.