The overexpression and activation of RARs have been implicated in the inappropriate behavior of cancer stem cells (CSCs) in malignancies such as AML, cholangiocarcinoma, colorectal cancer, clear cell renal cell carcinoma, hepatocellular carcinoma, prostate cancer, pancreatic ductal adenocarcinoma, and ovarian cancer (Bleul et al., 2015; Herreros-Villanueva et al., 2015; Guo et al., 2016; Wang et al., 2016; Fettig et al., 2017; Mezquita et al., 2018; Fan et al., 2021). This evidence concerns the gene RARS1 and cancer.