INTERNATIONAL CONGRESS OF
CancerGenetics
Expression investigation of PD-1, an immune system inhibitory marker, in tumor tissue of bladder cancer patients
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Ali Ariafar,1 Faezeh Gharechahi,2 Elham Taheri,3 Zohreh Bagheri,4 Seyedeh Hooriyeh Shapourian,5 Zahra Faghih,6,*
1. Department of Urology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
2. Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
3. Department of Pathology, School of Medicine, Shiraz University of Medical Sciences, Iran
4. Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
5. Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
6. Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
- Introduction: Programmed death protein 1 (PD-1) is introduced as one of the central immune checkpoint for regulating immune responses. as a key checkpoint for T cells, it hinders T cell function by tempting T cell exhaustion to promote immune invasion. Thus, regarding the crucial role of PD-1/PD-Ls pathway in the biology and immunotherapy of tumors, in the present study we aimed to assess the expression of PD-1 and its association with tumor prognosis and survival in Iranian patients with Bladder Cancer (BC).
- Methods: 129 untreated patients with BC who received surgical resection in hospitals affiliated with Shiraz University of Medical Sciences, Iran, from 1393 to 1400, were enrolled in the present study. The Hematoxylin and eosin (H&E) stained sections of selected patients were checked by an expert pathologist to select appropriate blocks. Then, three micrometer sections were prepared from formalin-fixed and paraffin-embedded tissue blocks and were stained with appropriate antibody specified for PD-1. After staining, the slides were examined by an expert pathologist, blinded to the clinical features and outcomes of the patients and the percentage of tumoral cells expressing the PD-1 was determined and reported separately in center and invasive margin of tumors.
- Results: Our results showed that PD-1 was expressed by bladder cancer cells mainly with cytoplasmic pattern, the frequency of PD-1+ tumoral cells varied widely among patients(0-60%). Statistical analysis indicated that PD-1 positivity among tumor cells in total cases and different regions (IM and CT) was strongly associated with muscle invasion, non-organ confined tumors, hifgh grade tumors and advanced tumor stages (P<0.05). However, univariate COX regression showed that patients with tumor cells expressing PD-1 in CT had prolonged survival (P=0.015).
- Conclusion: Taken together, our data demonstrated the association of PD-1 expression on tumor cells with poor prognosis of BC.
- Keywords: PD-1, Bladder cancer, Tumor cells
