KLF9 and neoplasm: For example, KLF family proteins have been shown to have either a tumor-promoting (KLF4 [2, 7], KLF6 [9], KLF9 [10], KLF10 [11], KLF11 [12], and KLF17 [13]) or a tumor-suppressing (KLF5 [14], KLF12 [15]) role by intervening in cell signaling associated with proliferation and/or suppression.