High-HDAC7 expression related to poor prognosis in sinonasal mucosal melanoma

Sinonasal mucosal melanoma (SNMM) is a rare malignant melanoma. Histone deacetylase 7 (HDAC7) is involved in the development of various tumours, but its function in SNMM remains underexplored. We retrospectively studied 30 patients with SNMM treated between 2013 and 2023. Immunohistochemistry was used to assess HDAC7, β-catenin, c-Myc, and Ki-67 expression. Relationships among HDAC7 expression, clinical characteristics, prognosis, β-catenin, c-Myc, and Ki-67 were analysed. HDAC7 was overexpressed in SNMM tissues compared to normal tissues. Expression was higher in stage IV compared to stage III and in T4 grade compared to T3 grade. The median overall survival (OS) was 29 months, with 8 patients alive. High-HDAC7 expression (in 13 patients) correlated with poorer OS and disease-free survival (DFS). HDAC7's carcinogenic role in SNMM may be mediated by β-catenin/c-Myc. Univariate analysis for OS revealed high-HDAC7, high c-Myc, positive surgical margins, T4 grade, and stage IV were significant factors leading to SNMM's poor prognosis. However, HDAC7 expression was the only independent prognostic factor. Additionally, a nomogram model showed promising results but was not validated in another cohort. High-HDAC7 expression is associated with advanced T grade, clinical stage, and poor prognosis in SNMM. HDAC7 may influence cell proliferation, invasion and migration by activating the Wnt/β-catenin/c-Myc signalling pathway.