Abstract
Non-Hodgkin lymphoma (NHL) consists of various lymphoid malignancies with a diverse clinical pathology and biological characteristics. Methylation of cytosine residues by DNA methyltransferases at CpG dinucleotides in the promoter region of the genes is a major epigenetic modification in mammalian genomes that can have profound effects on gene expression. The PTPL1 methylation pattern was screened by methylation‑specific polymerase chain reaction (MSP) in 7 lymphoma‑derived cell lines and in 47 samples of diffuse large B cell lymphoma (DLBCL). The PTPL1 gene was hypermethylated in the CA46, Raji, Jurkat and DB cell lines; however, it was unmethylated in the Hut78, Maver and Z138 cell lines. The expression of PTPL1 mRNA was re‑inducible by 5‑azacytidine (5‑Aza), an agent of DNA demethylation. The methylations were detected in 59.6% of DLBCL versus 6.3% in reactive lymph node proliferation. Therefore, the present data showed that PTPL1 was epigenetically regulated in NHL suggesting an involvement of the PTPL1 tumor‑suppressor genes in NHL, and highlights 5-Aza as a potential therapeutic candidate for NHL.