ESR1 and endometrial cancer: To study the anti-tumor activity of pterostilbene in endometrial cancer, we tested its effect on cell growth in two endometrial cancer cell lines, ECC-1, an ER/PR responsive cell line derived from a patient with a well-differentiated endometrial cancer, and HEC-1A, a cell line derived from an endometrial cancer patient with adenosquamous histology with moderate ER-α expression36–38.