Epigenetic silencing of a long non-coding RNA KIAA0495 in multiple myeloma.

In multiple myeloma, a long non-coding RNA, KIAA0495 (alias PDAM/TP73-AS1), had been found progressively downregulated from normal plasma cell to benign monoclonal gammopathy of undetermined significance to symptomatic myeloma. Herein, by methylation-specific PCR, the putative KIAA0495 promoter was found unmethylated in all healthy controls (N = 14) but methylated in 50 % of myeloma cell lines (N = 10). KIAA0495 methylation was shown inversely correlated with KIAA0495 expression. However, KIAA0495 methylation was detected in none of both primary myeloma samples at diagnosis (N = 61) and at relapse/progression (N = 16). Collectively, despite frequently methylated in cell lines, KIAA0495 methylation appeared unimportant in the pathogenesis or progression of myeloma.