Sekiya et al. reported a case of adenomatoid odontogenic tumor (AOT) in which estrogen receptors (located in tumor cell nuclei) were positive for B-cell lymphoma 2 (Bcl-2), suggesting that the survival of tumor cells was facilitated by Bcl-2 upon continuous stimulation of estrogen during pregnancy [20]. The gene discussed is ESR1; the disease is adenomatoid odontogenic tumor.