title: PD-1, PD-L1 and PD-L2 expression in mouse prostate cancer.
abstract: Programmed cell death protein 1 (PD-1) and its ligands PD-L1 and PD-L2 play critical roles in maintaining an immunosuppressive tumor microenvironment. The purpose of the present study was to assess expression of PD-1, PD-L1, and PD-L2 in mouse prostate tumors. A total of 33 mouse prostate tumors derived from Pten-null mice were examined using immunohistochemical staining for PD-1, PD-L1, and PD-L2. The animals were either with interleukin-17 receptor c (Il-17rc) wild-type or knockout genotype, or fed with regular diet or high-fat diet to 30 weeks of age. We found that Il-17rc wild-type mouse prostate tumors had significantly higher levels of PD-1, PD-L1, and PD-L2 than Il-17rc knockout mouse prostate tumors. High-fat diet-induced obese mice had significantly higher levels of PD-1, PD-L1, and PD-L2 in their prostate tumors than lean mice fed with regular diet. Increased expression of PD-1, PD-L1, and PD-L2 was associated with increased number of invasive prostate tumors formed in the Il-17rc wild-type and obese mice compared to the Il-17rc knockout and lean mice, respectively. Our findings suggest that expression of PD-1, PD-L1, and PD-L2 may enhance development of mouse prostate cancer through creating an immunosuppressive tumor microenvironment.
authors.affiliation: Department of Structural and Cellular Biology, Tulane UniversityNew Orleans, LA, USA; Department of Urology, The Third Hospital of Hebei Medical UniversityShijiazhuang, China.
authors.forename: Shijie
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Structural and Cellular Biology, Tulane University New Orleans, LA, USA.
authors.forename: Qiuyang
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Structural and Cellular Biology, Tulane University New Orleans, LA, USA.
authors.forename: Sen
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Pathology and Laboratory Medicine, Tulane University New Orleans, LA, USA.
authors.forename: Alun R
authors.initials: AR
authors.lastname: Wang
authors.affiliation: Department of Structural and Cellular Biology, Tulane UniversityNew Orleans, LA, USA; Tulane Cancer Center and Louisiana Cancer Research Consortium, Tulane UniversityNew Orleans, LA, USA; Department of Orthopaedic Surgery, Tulane UniversityNew Orleans, LA, USA; Tulane Center for Stem Cell Research and Regenerative Medicine, Tulane UniversityNew Orleans, LA, USA; Tulane Center for Aging, Tulane UniversityNew Orleans, LA, USA.
authors.forename: Zongbing
authors.initials: Z
authors.lastname: You
keywords: IL-17; PD-1; PD-L1; PD-L2; Prostate cancer; obesity