ESR1 and clear cell adenocarcinoma: However, despite the similarities between clear cell carcinomas and endometrioid carcinomas in ARID1A and PI3K-Akt pathway aberrations, protein array analysis showed differential expression between the two subtypes with endometrioid carcinomas expressing higher levels of steroid hormone receptors (ER and PR), and clear cell carcinomas expressing higher levels of Cyclin E, SMAD3, and e-cadherin [140].