PRRX1 and cancer: It was proposed that depleting sirtuin 1 (SIRT1) accelerates the degradation of paired related homeobox 1 (PRRX1) and disinhibits kruppel-like factor 4 (KLF4) transcription, leading to a partial MET, occurrence of aldehyde dehydrogenase 1 (ALDH1)-positive cancer stem cells, distant metastases and resistance to paclitaxel.