[Autophagy promotes recurrence of nasopharyngeal carcinoma via inducing the formation of dormant polyploid giant cancer cells].

Objective: To explore the effect of dormant polyploid giant cancer cells (PGCC) on nasopharyngeal carcinoma (NPC) recurrence and to clarify the role of inhibition of autophagy in inhibiting NPC-PGCC formation and preventing NPC recurrence. Methods: NPC cells-derived PGCC (NPC-PGCC) were induced by paclitaxel (PTX), and the morphology, polyploid characteristics and cell activity of PGCC were identified by light microscopy, immunofluorescence and Live/Dead cell double staining assays. RNA-seq was used to analyze the differentially expressed genes between NPC-PGCC and diploid nasopharyngeal carcinoma cells CNE2. Functional enrichment and pathway annotation analysis of differentially expressed genes were performed using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG). The level of autophagy in NPC-PGCC cells was assessed by Western Blot and transmission electron microscopy analysis. The role of autophagy in the formation of NPC-PGCC and the effect of NPC-PGCC on the recurrence of nasopharyngeal carcinoma were studied using a highly clinically relevant mouse nasopharyngeal carcinoma recurrence model. Statistical analysis was performed using GraphPad Prism 6 and P-values<0.05 were considered statistically significant. Results: NPC-PGCC induced by paclitaxel had the characteristics of burst-like division after dormancy. GO enrichment and KEGG pathway analyses identified the significant biological processes and pathways mainly concentrated in autophagy and related pathways involving the differentially expressed genes between NPC-PGCC and diploid nasopharyngeal carcinoma cells CNE2. The autophagy level was significantly enhanced in NPC-PGCC cells. In a highly clinically relevant mouse nasopharyngeal carcinoma recurrence model, the number of PGCC in the primary tumor of the nude mice treated with cisplatin were higher than those of the other groups. In nude mice pretreated with autophagy inhibitor and then co-treatment with autophagy inhibitor and cisplatin, the number of PGCC in primary tumors was less and the recurrence rate was significantly lower than in other groups. Conclusions: The mechanism of dormant polyploid giant cancer cells formation is related to autophagy. Inhibition of autophagy can inhibit the formation of PGCC and thus prevent the recurrence of nasopharyngeal carcinoma.

[Research of SIRT1 on promoting the proliferation, migration and lipid metabolism of nasopharyngeal carcinoma].

Objective: To analyze the differential expression of silent information regulator transcript-1 (SIRT1) in tissues and cells of nasopharyngeal carcinoma (NPC), to explore the effects of SIRT1 on the proliferation and migration of NPC cells, as well as the effects on and mechanisms of lipid metabolism in NPC cells. Methods: Experimental subjects: In this study, tissue specimens were obtained from patients who visited the Department of Otolaryngology and performed nasopharyngeal tissue biopsy in the Affiliated Hospital of Nantong University from 2019 to 2020. Among them, 6 cases were male, 6 cases were female, age range: 27-72 years old, including 7 cases of NPC diagnosed by pathology and 5 cases of normal nasopharyngeal mucosa. Experimental methods and outcome measures: Western Blot and quantitative real time polymerase chain reaction (qRT-PCR) were used to detect the protein and mRNA levels of SIRT1. CNE2 cell line was selected for subsequent experiments. Cell viability and migratory ability were evaluated by CCK8, wound healing and Transwell assays respectively. Animal xenograft tumor model was used to explore the role of SIRT1 inhibitor Ex527 on tumor growth in nude mice. Oil red and Bodipy were used to stain intracellular lipids. For the mechanical investigation, the interactions between SIRT1 and hypoxia inducible factor-1α (HIF-1α) were analyzed by immunoprecipitation (IP) and chromatin immunoprecipitation (ChIP). Finally, statistical analysis was performed by SPSS 26.0 software, P<0.05 was considered statistically significant. Results: The levels of SIRT1 protein (1.005±0.168) and mRNA (5.829±2.395) in NPC tissues were higher than those in normal nasopharyngeal mucosa (0.181±0.042,1.995±1.605). Differences were statistically significant (t values were 6.438 and 2.759, both P<0.05). The mRNA and protein levels of CNE1, CNE2, 5-8F and 6-10B cell lines were also higher than those in normal nasopharynx epithelial cell line NP69. Besides, overexpression of SIRT1 correlated with the proliferation and migration of NPC cells. The tumorigenesis ability of nude mice in the Ex527 group was lower than that in the control group. The low SIRT1 expression reduced the protein level of the key enzymes of liposynthesis in NPC cells, improved the expression of lipolysis enzymes, while HIF-1α overexpression promoted lipid synthesis enzymes in NPC cells. SIRT1 inhibited HIF-1α transcription by enhancing deacetylation levels. The binding ability of HIF-1α to SIRT1 promoter regions decreased when NPC cells were hypoxic. Conclusions: SIRT1 promotes the proliferation, migration and lipid metabolism of nasopharyngeal carcinoma cells, which might be expected to provide new theoretical basis for prognosis judgment and gene therapy.

[The clinical features of patients with allergic rhinitis of Nantong city in China].

Objective:To comprehensively analyze the clinical features of patients with AR by a retrospective study. Method:A total number of 8 102 patients diagnosed with AR were enrolled in Nantong area, and detailed clinical data were documented in all cases. Skin prick tests with standardized aeroallergens were conducted in these patients; The samples were divided into two groups(children and adults group) and the clinical features between two groups were analysed. Result:Children in schoolage were the majority of AR patients in children group. There were 4 581 cases(56.54%) with ocular symptoms, 3 977 cases(49.09%)with lower respiratory tract symptoms. Nasal congestion (97.37%) was the most common symptoms in patients with AR,while eye itching(32.68%) was the most common ocular symptoms in patients with AR, followed by the dacryorrhea(23.57%);and cough(44.72%) was the most common lower respiratory tract symptoms. Dermatophagoides pteronyssinus and dermatophagoides farinae had the highest positivity among all allergens, and the shrimp was the main food allergen. Conclusion:We analyzed the clinical features of patients with AR, that would provide a more scientific basis for prevention,clinical diagnosis, treatment and epidemiological studies for AR.