An investigation of PD-L1 expression and its association with tumor infiltrating T cells in human cervical carcinomas

International Conference & Exhibition on Cancer Science & Therapy

15-17 August 2011 Las Vegas, USA

Xu Man, Wang Yuqi, Xu Guangxu, Geng Weipu and Tang Junying

Department of Pathology, Molecular Medicine and Cancer Research Center
Gynecology of the first affiliate hospital, Chongqing Medical University, China

Scientific Tracks Abstracts: J Cancer Sci Ther

Abstract :

Purpose: To observe the expression of Programmed death receptor-ligand 1(PD-L1) and the association between PD-L1 expression and T cell infiltration in human cervical carcinomas. Methods : PD-L1 and PD-1 expression was respectively determined in five cases of normal cervical tissue, 7 cases of highlevel cervical intraepithelial neoplasia (CIN II-III) and 67 cases of cervical carcinomas by immunohistochemistry staining; the tumor infiltrating CD4+T and CD8+T cells were determined by immunofluorescent staining, and the apoptosis of tumor infiltrating lymphocytes was examined by TUNEL assay in those cases. Results: No PD-L1 expressed in normal cervical epithelium; PD-L1 negatively or weakly expressed in epithelia of high grade CIN, the average relative optical density was 0.82 �± 0.75; and PD-L1 expressed in 70% (47/67) cervical carcinomas, the average relative optical density in superficial infiltrating (<0.5 cm) and deep infiltrating cervical squamous cell carcinomas was 2.70 �± 1.68 and 2.90 �± 1.72. PD-1 expressed in partial tumor infiltrating lymphocytes in those cases. PD-L1 expression density of cervical carcinomas was significantly higher than that of CIN (P<0.01); PD-L1 expression density of superficial invasive cervical carcinomas was slightly lower than that of deep invasive cases, but there was no significant statistic difference between them; in addition, PD-L1 expression negatively associated with the number of tumor infiltrating CD8+T cells(r =-0.82, P<0.01), but not with the number of CD4+T cells (r =-0.05, P> 0.05). Apoptosis occurred in partial tumor infiltrating lymphocytes of cervical carcinomas. Conclusion: Human cervical carcinoma cells express PD-L1, and it negatively associates with the number of tumor infiltrating CD8+T cells, but not with the number of CD4+T cells. PD-L1 expression of tumor cells may play role on apoptosis of tumor infiltrating lymphocytes.