HDAC9 and cervical squamous cell carcinoma: Therefore, we designed this study to quantify the level of acetylated histone H3 and the aberrant expression of RARβ2 and the E-cadherin/β-catenin complex in biopsies of cervical squamous cell carcinoma patients using immunohistochemistry, to determine the relationship between the expression levels of these markers and the clinicopathological features of the patients, and to evaluate the therapeutic efficacy of the HDAC inhibitor VPA combined with ATRA by targeting chromatin remodelling and RARβ expression.