METTL3-mediated m6A modification promotes processing and maturation of pri-miRNA-19a to facilitate nasopharyngeal carcinoma cell proliferation and invasion.

The interplay between N6-methyladenosine (m6A) modification and microRNAs (miRs) participates in cancer progression. This study is conducted to explore the role of miR-19a-3p in nasopharyngeal carcinoma (NPC) cell proliferation and invasion. Reverse transcription quantitative polymerase chain reaction and Western blot showed that miR-19a-3p was upregulated in NPC tissues and cells and related to poor prognosis, methyltransferase-like 3 (METTL3) was highly expressed, whereas BMP and activin membrane-bound inhibitor (BAMBI) was weakly expressed in NPC tissues and cells. miR-19a-3p downregulation inhibited cell proliferation and invasion, whereas miR-19a-3p overexpression played the opposite role. m6A quantification and m6A RNA immunoprecipitation assays showed that METTL3-mediated m6A modification promoted the processing and maturation of pri-miR-19a via DiGeorge syndrome critical region gene 8 (DGCR8). Dual-luciferase assay showed that BAMBI was a target of miR-19a-3p. The rescue experiments showed that BAMBI downregulation reversed the role of miR-19a-3p inhibition in NPC cells. A xenograft tumor model showed that METTL3 downregulation inhibited tumor growth via the miR-19a-3p/BAMBI in vivo. Overall, our findings elicited that METTL3-mediated m6A modification facilitated the processing and maturation of pri-miR-19a via DGCR8 to upregulate miR-19a-3p, and miR-19a-3p inhibited BAMBI expression to promote NPC cell proliferation and invasion, thus driving NPC progression.

The diagnosis and treatment of a variant type of auricular sinus: postauricular sinus.

OBJECTIVES: To make otolaryngologists aware of the variant types of auricular sinus, we have performed a systematic review of patient diagnoses and presented our operative experiences. METHODS: From 2009 to 2013 in Sun Yat-Sen Memorial Hospital, there was a total of 20 children with the variant type of auricular sinuses including the comprehensive group. Postauricular sinuses have pits located posterior to the imaginary vertical line that is tangent to the external auditory canal. Sinuses that penetrate the cartilage and cause postauricular swelling or skin defects characterize type 1 of the variant type, while sinuses that adhere to the cartilage and cause preauricular or auricular swelling or skin defects characterize type 2. Patients with pits both anterior to and posterior to the imaginary vertical line comprise the comprehensive group. The patients who had infected underwent auricular sinusectomy using a dual approach, with accurate fistula tracing and proper cartilage removal. RESULTS: Sixteen children who had infected sinus underwent surgery, while the other four were asymptomatic. Ten children (62.5%) of 16 patients were diagnosed as type 1 of the variant type, 2 (12.5%) as type 2. Four children (25%) were diagnosis as the comprehensive group. The asymptomatic could not be defined as the sinuses location were unknown. Sixteen children (100%) of 16 patients who underwent surgery had a history of misdiagnosis and treatment. These patients did not experience recurrence over a 5-year follow-up period. CONCLUSION: The locations of pits and sinuses help to categorize the different types of auricular sinus. The effective method that we have described should be considered a viable way to reduce recurrence.

FTH1 indicates poor prognosis and promotes metastasis in head and neck squamous cell carcinoma.

Background: Currently, ferritin heavy chain (FTH1) has been increasingly found to play a crucial role in cancer as a core regulator of ferroptosis, while its role of non-ferroptosis in head and neck squamous cell carcinoma (HNSCC) is still unclear. Methods: Herein, we analyzed the expression level of FTH1 in HNSCC using TCGA database, and FTH1 protein in HNSCC tissues and cell lines was determined by immunohistochemistry (IHC) and western blotting, respectively. Then, its prognostic value and relationship with clinical parameters were investigated in HNSCC patients. Additionally, the biological function of FTH1 in HNSCC was explored. Results: The current study showed that FTH1 is significantly overexpressed in HNSCC tissues and related to poor prognosis and lymph node metastasis of HNSCC. FTH1 knockdown could suppress the metastasis and epithelial-mesenchymal transition (EMT) process of HNSCC. Conclusion: Our findings indicate that FTH1 plays a critical role in the progression and metastasis of HNSCC and can serve as a promising prognostic factor and therapeutic target in HNSCC.