Study Expression of HDAC3 and HDAC6 in Women with Breast Cancer under Chemotherapy and Immunotherapy

Abstract

Breast cancer exhibits considerable heterogeneity in its molecular and clinical features, and is one of the most common cancers among women worldwide. It has multiple causes, including genetic and non-genetic factors. It also poses a major challenge in diagnosis and therapeutic monitoring, especially in light of the complexity of the tumor's immune environment and the variability of responses to treatment. The current study aimed to investigate some molecular biomarkers. The gene expression of Histone Deacetylase 3 (HDAC3) and Histone Deacetylase 6 (HDAC6) was evaluated in breast cancer patients undergoing chemotherapy and immunotherapy, compared to a control group of healthy women. The study included 40 patients previously diagnosed with breast cancer by the medical staff at the Salah al-Din Oncology Center, during the period from July 2024 to August 2024, in addition to 20 healthy female participants (controls). Women with breast cancer were divided into two groups according to the type of treatment: the first group (chemotherapy group) included 20 samples. The second group (immunotherapy group) included 20 samples. The third group was the control group, with 20 samples. Gene expression was quantified using RT-qPCR. The results showed that HDAC3 gene expression was significantly decreased in the patient group compared to the control group (p=0.006), with the decrease being more pronounced in the chemotherapy group, reaching (p=0.003) compared to the control group. As for HDAC6, gene expression was significantly decreased in patients compared to the control group (p=0.047). Although lower values ​​were recorded in the chemotherapy group, the differences between the groups were not statistically significant (p>0.05). Meanwhile, ROC analysis showed that HDAC3 had a higher diagnostic ability (p=0.009, AUC=0.701) compared to HDAC6, which had a moderate diagnostic ability (p=0.042, AUC=0.659). Correlation analysis results also revealed a strong positive relationship between HDAC3 and HDAC6 (r=0.679, p<0.001), while no statistically significant correlation was recorded between immune variables and age. These findings suggest that the molecular markers HDAC3 and HDAC6 may play an important role in regulating the tumor immune environment and determining treatment response, and may serve as promising markers for breast cancer diagnosis and monitoring. However, further studies are needed to determine their prognostic significance and therapeutic implications, particularly in the context of combination therapies.