Programmed cell death ligand-1 expression in gastroenteropancreatic neuroendocrine tumors

Oktay E., Yalcin G. D., Ekmekci S., Kahraman D. S., Yalcin A., Degirmenci M., ...Daha Fazla

Journal of B.U.ON., cilt.24, sa.2, ss.779-790, 2019 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 24 Sayı: 2
  • Basım Tarihi: 2019
  • Dergi Adı: Journal of B.U.ON.
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.779-790
  • Anahtar Kelimeler: GEP carcinomas, GEPNET, Immunohistochemistry, PD-1, PD-L1, RT=PCR
  • Manisa Celal Bayar Üniversitesi Adresli: Evet

Özet

Purpose: Gastroenteropancreatic tumors (GEPNETs) is a heterogeneous disease with variable clinical course. While promising therapeutic options exist for other adult cancers, there are no new molecular-based treatments developed for GEPNETs. One of the main targets of cancer immunotherapy is the Programmed Cell Death Ligand-1 (PD-L1) pathway. Our purpose was to investigate the profile of PD-L1 expression in different organs of GEPNETs and compare the conventional immunohistochemistry (IHC) with the RNA expression analysis via real time polymerase chain reaction (RT-PCR) in order to determine which patients might be appropriate for immune check point-targeted therapy. Methods: A total of 59 surgically or endoscopically resected GEPNET tissues were retrospectively collected. The expression of PD-L1 and mRNA was evaluated with IHC. Results: The expression of PD-L1 was significantly associated with the high-grade classification (p=0.012). PD-L1 mRNA expression in tumor samples appeared to be higher compared to the corresponding normal tissues. In appendix, stomach and small intestine, the expression of PD-L1 mRNA was higher in the tumor tissues compared to the respective controls. In pancreas and colon, control tissues tend to have a higher PD-L1 mRNA expression compared to tumor tissues. PD-L1 mRNA expression was higher in GEP carcinomas (p=0.0031). Conclusion: RT-PCR was found to be more sensitive in detecting PD-L1 expression than conventional IHC. This study may provide an important starting point and useful background information for future research about immunotherapy for appendix, stomach and small intestine neuroendocrine carcinomas.