As revealed in Figure 4, the phosphorylation levels of JAK2, STAT3, PI3K and AKT were downregulated in the absence of KLF3 in both A549 and 95D cells in vitro, suggesting that JAK2/STAT3 and PI3K/AKT signalling pathways may be involved in lung cancer progression regulated by KLF3. This evidence concerns the gene KLF3 and lung cancer.