DNMT3A and small cell lung carcinoma: Given the crucial roles played by coordinated histone methylation and DNA methylation driven by KMT2C and DNMT3A deficiencies, respectively, during SCLC metastasis progression, researchers have proposed SAM (S-adenosylmethionine), a common substrate for both histones and DNMTs, as a proof-of-concept inhibitor for SCLC metastasis treatment.