Histone Deacetylase-2 Expression in Colorectal Cancer: An Immunohistochemical Study and Its Clinicopathological Significance

Background/Objectives: Colorectal cancer (CRC) remains a leading cause of cancer-related mortality and is characterized by substantial molecular heterogeneity, including epigenetic dysregulation. Histone acetylation, regulated by histone acetyltransferases and histone deacetylases (HDAC), has been implicated in CRC development and progression. The aim of the present study was to evaluate HDAC-2 expression in CRC and investigate its association with clinicopathological parameters and patient outcomes. Methods: In this retrospective study, tumor tissue samples from 77 patients with CRC and documented recurrence were examined. HDAC-2 expression was assessed by immunohistochemistry and classified as low or high using a semi-quantitative scoring system. Associations with clinicopathological parameters and survival outcomes (disease-free survival, DFS; overall survival, OS) were analyzed. Results: High HDAC-2 expression was associated with younger patient age and earlier disease recurrence, while its association with overall survival was borderline. Conclusions: HDAC-2 expression may have clinicopathological relevance in CRC, particularly in relation to recurrence-related outcomes, although larger studies are needed to confirm its prognostic significance.