Browsing by Author "Calado, Sofia M."
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- Interferon-alpha decreases cancer stem cell properties and modulates exosomes in malignant melanomaPublication . García-Ortega, María Belén; Aparicio, Ernesto; Griñán-Lisón, Carmen; Jiménez, Gema; López-Ruiz, Elena; Palacios, José Luis; Ruiz-Alcalá, Gloria; Alba, Cristina; Martínez, Antonio; Boulaiz, Houria; Perán, Macarena; Hackenberg, Michael; Bragança, José; Calado, Sofia M.; Marchal, Juan A.; García, María ÁngelMalignant melanoma (MM) can spread to other organs and is resistant in part due to the presence of cancer stem cell subpopulations (CSCs). While a controversial high dose of interferon-alpha (IFN-α) has been used to treat non-metastatic high-risk melanoma, it comes with undesirable side effects. In this study, we evaluated the effect of low and high doses of IFN-α on CSCs by analyzing ALDH activity, side population and specific surface markers in established and patient-derived primary cell lines. We also assessed the clonogenicity, migration and tumor initiation capacities of IFN-α treated CSCs. Additionally, we investigated genomic modulations related to stemness properties using microRNA sequencing and microarrays. The effect of IFN-α on CSCs-derived exosomes was also analyzed using NanoSight and liquid chromatography (LC-HRMS)-based metabolomic analysis, among others. Our results showed that even low doses of IFN-α reduced CSC formation and stemness properties, and led to a significant decrease in the ability to form tumors in mice xenotransplants. IFN-α also modulated the expression of genes and microRNAs involved in several cancer processes and metabolomics of released exosomes. Our work suggests the utility of low doses of interferon, combined with the analysis of metabolic biomarkers, as a potential clinical approach against the aggressiveness of CSCs in melanoma.
- pEPito-driven PEDF Expression Ameliorates Diabetic Retinopathy HallmarksPublication . Calado, Sofia M.; Diaz-Corrales, Francisco; Silva, Gabriela A.Diabetic retinopathy (DR) is one of the major complications of diabetes mellitus. It is characterized by retinal microvascular changes caused by chronic exposure to hyperglycemia, leading to low tissue oxygenation and ultimately to neovascularization. Laser photocoagulation and vitrectomy are the most efficient treatments for DR, but display severe side effects such as the destruction of the healthy retina. Another clinical approach uses antiangiogenic agents to prevent and delay progression of neovascularization, but these require recurrent local administrations that increase the possibility of retinal detachment, vitreous hemorrhage, and cataract formation. Studies in human diabetic retinas have revealed an imbalance between proangiogenic factors such as the vascular endothelial growth factor (VEGF) and antiangiogenic factors, such as pigment epithelial-derived factor (PEDF). This imbalance favors pathological angiogenesis contributing to DR, and can constitute a therapeutic target. Gene therapy was recently shown to be an adequate intervention for long-term treatment of several retinal pathologies. We have previously shown the newly engineered episomal vector pEPito to be able of sustained gene expression in the mouse retina. We here show that pEPito was able to overexpress PEDF for up to three months, both in in vitro cultures of human retinal pigment epithelial cells and in the retina of diabetic mice after a single subretinal injection. In vivo, in parallel with the increase in PEDF we observed a decrease in VEGF levels in injected compared with noninjected eyes and a significant effect on two hallmarks of DR: reduction of glucose transport (by glucose transporter GLUT1), and reduction of inflammation by decreased reactivity of microglia. Jointly, these results point to a significant therapeutic potential of gene therapy with pEPito-PEDF for the treatment of DR.