Abstract:Objective: To investigate the effect of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and pepsin on local invasion of laryngeal squamous cell carcinoma. Methods: From October 2020 to March 2022, fresh specimens of cancer tissue and paracancerous tissue from 32 patients with laryngeal cancer who underwent inpatient surgery in the otolaryngology department of Liuzhou People's Hospital and were pathologically diagnosed were collected. During the same period, fresh specimens of 29 adult pharyngeal papilloma tissues and adjacent tissues were collected. The expressions of MMP-2, MMP-9 and Pepsin mRNA in the above tissue samples were detected by real-time fluorescence quantitative PCR (qRT-PCR), and analyzed in combination with clinical data. Results: The expression of MMP-2, MMP-9 and Pepsin mRNA in laryngeal carcinoma tissues was higher than that in adjacent tissues (P<0.05). The expression level in stage III and IV groups was higher than that in stage I and II groups (P<0.05), and that in lymph node metastasis group was higher than that in non-metastasis group (P<0.05). The expression of MMP-2 mRNA and MMP-9 mRNA in medium-low differentiated squamous cell carcinoma group was higher than that in well differentiated group (P<0.05); the expression of Pepsin mRNA in laryngeal carcinoma group aged 60 years or older was higher than that in laryngeal carcinoma group aged less than 60 years (P<0.05); the expression of MMP-2 mRNA, MMP-9 mRNA and Pepsin in laryngeal carcinoma tissue was higher than that in papilloma and adjacent tissue group (P<0.05). In addition, the expression levels of MMP-2, MMP-9 and Pepsin mRNA increased from paratumoral tissue, papilloma tissue to laryngeal carcinoma tissue. Conclusion: MMP-2, MMP-9 and Pepsin play a coordinated role in local invasion of squamous carcinoma of the larynx. Prevention and treatment of laryngopharyngeal reflux is an important part of preventing the local invasion of laryngeal carcinoma.