SET and MYND domain-containing protein 2, also known as HSKM-B, SMYD2, and KMT3C, is a member of the SMYD protein family. It contains one MYND-type zinc finger and one SET domain. Not much is known about SMYD2. However, the interest in better understanding the roles of SMYD2 has grown because of reports indicating that SMYD2 methylates p53 and histone H3. In Xenopus, SMYD1 and SMYD2 were expressed in various muscle tissues and related to muscle cell differentiation. SMYD2 mRNA is most highly expressed in heart and brain tissue. Over-expressed SMYD2 localizes to the cytoplasm and the nucleus in 293T cells. SMYD2 appears to restrain cell proliferation, likely through direct modulation of chromatin structure. Patients with SMYD2-overexpressing tumors had a worse overall rate of survival than those with non-expressing tumors, and SMYD2 positivity was independently associated with a worse outcome in the multivariate analysis. SMYD2 plays an important role in tumor cell proliferation through its activation/overexpression and regards as a prognosticator and potential therapeutic target in esophageal squamous cell carcinoma (ESCC).