RESUMO
Epithelial ovarian cancer (EOC) is the most lethal gynecological cancer. The current treatment for EOC involves surgical debulking of the tumors followed by a combination of chemotherapy. While most patients achieve complete remission, many EOCs will recur and develop chemo-resistance. The cancer cells can adapt to several stress stimuli, becoming resistant. Because of this, new ways to fight resistant cells during the disease are being studied. However, the clinical outcomes remain unsatisfactory. Recently, ferroptosis, a novel form of regulated cell death trigged by the accumulation of iron and toxic species of lipid metabolism in cells, has emerged as a promising anti-tumor strategy for EOC treatment. This process has a high potential to become a complementary treatment to the current anti-tumor strategies to eliminate resistant cells and to avoid relapse. Cancer cells, like other cells in the body, release small extracellular vesicles (sEV) that allow the transport of substances from the cells themselves to communicate with their environment. To achieve this, we analyzed the capacity of epithelial ovarian cancer cells (OVCA), treated with ferroptosis inducers, to generate sEV, assessing their size and number, and study the transmission of ferroptosis by sEV. Our results reveal that OVCA cells treated with ferroptotic inducers can modify intercellular communication by sEV, inducing cell death in recipient cells. Furthermore, these receptor cells are able to generate a greater amount of sEV, contributing to a much higher ferroptosis paracrine transmission. Thus, we discovered the importance of the sEV in the communication between cells in OVCA, focusing on the ferroptosis process. These findings could be the beginning form to study the molecular mechanism ferroptosis transmission through sEV.
RESUMO
PURPOSE: Obstructive sleep apnea (OSA) is a sleep breathing disorder with unclear multifactorial pathogenesis. This study aimed to investigate the association between OSA and two human leukocyte antigens (HLA) alleles; DQB1*0602 and DRB1*15. METHODS: Forty patients with OSA and 40 control subjects were enrolled in the study. OSA diagnosis was made utilizing the Apnea-Hypopnea Index (AHI)≥5 in overnight polysomnography (PSG). AHI was also used to determine OSA severity. Controls were randomly selected from healthy volunteers who had a low risk for OSA, utilizing the Berlin Questionnaire. Polymerase chain reaction (PCR) using Sequence Specific Primers (PCR-SSPs) was used to determine the association between HLA (HLA-DQB1*0602 and HLA-DRB1*15) and OSA, then statistical analyses of the results were performed. RESULTS: HLA-DQB1*0602 allele was found in 85% of all OSA patients and 50% of controls (P< 0.001). In patients with severe OSA, HLA-DQB1*0602 was present in the 92.9% compared with 66.7% in non-severe OSA (P=0.05). HLA-DRB1*15 allele was found in 15% of OSA patients and 20% of controls, with no difference between the two groups (P=0.556). No statistical difference was found in HLA-DRB1*15 between severe and non-severe OSA (P=0.499). After adjusting for gender, HLA-DQB1*0602 allele was associated with increased odds of OSA (OR = 6.17, 95% CI 1.87-20.3, p = 0.003), but HLA-DRB1*15 allele was not associated with OSA (OR 0.45, 95% CI 0.12-1.73, p = 0.242). CONCLUSIONS: The presence of HLA-DQB1*0602 allele, but not HLA-DRB1*15 allele, was significantly associated with OSA.
