SP4 and gastric cancer: Although the patterns of SP1 protein levels in gastric cancer cell lines were not directly correlated with the patterns of SP3 and SP4 protein levels (Figure S1B), CXCL10, ACVRL1, and CDKN2D in MKN28 can also be regulated by SP3 and SP4 in a similar manner to SP1 (data not shown), suggesting that different SP transcription factors can regulate the same gene [28]–[30].