Because the phosphorylation of HSP27 facilitates the ubiquitination and proteasomal breakdown of proteins that drive stemness (including NANOG, OCT4, c-Myc, SOX2, and KLF4) in non-small-cell lung cancer (NSCLC) cells, the inactivation of p38 promotes the expression of CSC characteristics [87]. Here, KLF4 is linked to non-small cell lung carcinoma.