KMT5B and glioblastoma: To delve into the possible role of KMT5B epigenetic repression in GBM, we stably transfected either a KMT5B expression plasmid or an empty vector (mock) into the human GBM cell line LN-229, which exhibits hypo-hydroxymethylation and downregulation of KMT5B. Two clones, namely KMT5B #3 and KMT5B #7, were selected among those that were drug resistant, and the expression of KMT5B was confirmed by qRT-PCR (Figure 3A).