Evaluation of Placental Alkaline Phosphatase Expression as A Potential Target of Solid Tumors Immunotherapy by Using Gene and Protein Expression Repositories.

Placental alkaline phosphatase (PLAP) is a membrane enzyme mainly expressed in the placenta. PLAP is shown to be expressed in ovarian cancer (OV), however, there is little known about its expression in other cancers. Using gene and protein expression deposited data, we surveyed PLAP expression across malignant and normal human tissues to explore the potential of PLAP as an immunotherapy target. We detected more than two-fold increased PLAP expression in multiple solid tumors including ovarian cancer, testicular germ cell tumors (TGCT), and uterine corpus endometrial carcinoma (UCEC) compared with matched normal tissues. We also showed association of PLAP expression with high mortality pancreatic adenocarcinoma (PAAD). Altogether, our results suggest that PLAP can be a promising target for immunotherapy of multiple cancers, especially OV, TGCT, and UCEC.