HDAC2 and metastatic malignant neoplasm in the lymph nodes: Interestingly, the presence of lymph node metastasis was associated with lower levels of HDAC-2 expression, which was an association that was stronger in tumors with serous histology (Mann–Whitney U test, p = 0.045, Figure 3) and was of borderline significance in the whole cohort (p = 0.081).