Beclin-1 and HIF-1α immunohistochemical expression in breast carcinoma: insights into tumor biology

Abstract

Breast carcinoma is a biologically heterogeneous disease in which tumor behavior and clinical outcome are influenced by multiple cellular pathways, including autophagy and hypoxia. Beclin-1, a key autophagy-related protein, and hypoxia-inducible factor-1α (HIF-1α), a central regulator of cellular responses to hypoxia, have both been implicated in breast cancer; however, their clinicopathological significance remains incompletely characterized. This study aimed to evaluate the immunohistochemical expression of Beclin-1 and HIF-1α in breast carcinoma and to assess their associations with clinicopathological features, molecular subtypes, and survival outcomes. This retrospective cohort study included 86 cases of invasive breast carcinoma diagnosed between 2014 and 2019. Tissue microarrays were constructed, and immunohistochemical staining for Beclin-1 and HIF-1α was performed. Beclin-1 expression was assessable in 82 cases and showed no significant association with clinicopathological features or survival outcomes. HIF-1α expression was evaluable in 79 cases and was significantly associated with age and lymph node positivity, but not with other clinicopathological variables or survival outcomes. A statistically significant positive correlation was observed between Beclin-1 and HIF-1α immunohistochemical expression. In conclusion, Beclin-1 and HIF-1α expression appear to reflect underlying tumor characteristics rather than serving as independent prognostic markers, while the association between HIF-1α expression and lymph node involvement supports a potential role for hypoxia-related pathways in regional tumor spread. Further larger studies are warranted to validate these findings.