HDAC9 and benign prostatic hyperplasia: Out of 12 members in BPH, six shared similarity with the classic HDAC family of zinc-dependent deacetylases, designated NlHDAC1, NlHDAC3, NlHDAC4, NlHDAC6, NlHDAC11 and NlHDAC11_like (NlHDAC11_l); the remaining six members were close to the sirtuin family of NAD+-dependent deacetylases, designated NlSIRT1–4, NlSIRT6 and NlSIRT7.