Platelet-activating Factor receptor ligands Protect Tumor cells from radiation-induced cell Death

Autor(es)

da Silva-Junior, Ildefonso Alves ^[1] ; Dalmaso, Barbara ^[1] ; Herbster, Suellen ^[1] ; Lepique, Ana Paula ^[1] ; Jancar, Sonia ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Ciencias Biomed, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: FRONTIERS IN ONCOLOGY; v. 8, FEB 5 2018.
• Citações Web of Science: 6

Resumo

Irradiation generates oxidized phospholipids that activate platelet-activating factor receptor (PAFR) associated with pro-tumorigenic effects. Here, we investigated the involvement of PAFR in tumor cell survival after irradiation. Cervical cancer samples presented higher levels of PAF-receptor gene (PTAFR) when compared with normal cervical tissue. In cervical cancer patients submitted to radiotherapy (RT), the expression of PTAFR was significantly increased. Cervical cancer-derived cell lines (C33, SiHa, and HeLa) and squamous carcinoma cell lines (SCC90 and SCC78) express higher levels of PAFR mRNA and protein than immortalized keratinocytes. Gamma radiation increased PAFR expression and induced PAFR ligands and prostaglandin E2 (PGE2) in these tumor cells. The blocking of PAFR with the antagonist CV3938 before irradiation inhibited PGE2 and increased tumor cells death. Similarly, human carcinoma cells transfected with PAFR (KBP) were more resistant to radiation compared to those lacking the receptor (KBM). PGE2 production by irradiated KBP cells was also inhibited by CV3988. These results show that irradiation of carcinoma cells generates PAFR ligands that protect tumor cells from death and suggests that the combination of RT with a PAFR antagonist could be a promising strategy for cancer treatment. (AU)

• Processo FAPESP: 17/08904-7 - O Receptor do PAF na repopulação tumoral induzida por Radioterapia
• Beneficiário: Ildefonso Alves da Silva Junior
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado