Clinical stage-dependent expression of MRE11 and its association with laryngeal cancer progression

Background: Radiotherapy is a mainstay of treatment for laryngeal cancer. MRE11, a core component of the MRN complex, contributes to radioresistance and also has a signalling function. This study examines the association between MRE11 expression and tumour progression in patients with laryngeal cancer treated at Bulovka University Hospital in Prague. Materials and methods: This retrospective study included 108 patients with laryngeal cancer treated with radiotherapy. Immunohistochemical analysis was performed on pretreatment biopsy samples to evaluate the expression of selected DNA repair proteins and statistically assess their impact on treatment outcomes. Results: Of the proteins studied, MRE11 showed the strongest statistical association, with significantly higher expression in early clinical stages I-II and lower expression in stages III-IV (p < 0.001). Higher MRE11 expression was associated with better overall survival (p < 0.001) and longer progression-free survival (p = 0.025). No significant relationship was observed between analysed protein expression and treatment toxicity. Conclusions: In our cohort of patients with laryngeal carcinoma treated with radiotherapy, elevated immunohistochemical expression of MRE11 was associated with less advanced disease and improved treatment outcomes, in contrast to findings in other head and neck cancers. This discrepancy may reflect the context-dependent function of MRE11. Further research is needed to clarify the prognostic role of MRE11 and its potential use in guiding personalised treatment.