Previous studies have demonstrated that SUMOylation modulates KLF4 activity—for instance, SUMO1 conjugation promotes KLF4-mediated M2 macrophage polarization, while SENP1-mediated de-SUMOylation of KLF4 drives M1 polarization via NF-κB activation and influences cancer cell behavior [31]; Nie et al. demonstrated that SUMO1 conjugation of KLF4 is critical for transcriptional corepressor binding at the p21 promoter, a key event in modulating VSMC proliferation [32]. This evidence concerns the gene SUMO1 and cancer.