The METTL3-D splice variant has an opposite function to that of the downstream genes of the canonical full-length METTL3-A. (A) RT–qPCR analyses of the mRNA levels of downstream target genes in METTL3-A- or METTL3-D-overexpressing HepG2 cells. SOCS2 and BATF2 were previously reported as mRNA stability-decreased target genes of METTL3, while EGFR and TAZ were previously reported as mRNA translation-affected target genes [31,32,33]. (B) mRNA levels of SOCS2 and BATF2 in two HCC patients. Compared with patient #58, patient #23 had higher levels of METTL3-D and higher levels of SOCS2 and BATF2. (C) Correlation coefficient between METTL3-D and BATF2 expression in HCC patients. The original data were downloaded from GEPIA2. The data in the bar graphs are expressed as means ± SD. * p < 0.05, ** p < 0.01, **** p < 0.0001 (t test).