Browsing by Author "Brebi, Priscilla"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Effects of c-FLIPL Knockdown in Cervical Uterine Carcinoma Cell Lines
    (2015) Ili, Carmen G.; Brebi, Priscilla; García Cañete, Patricia; Leal, Pamela; Lopez, Jaime; Tapia, Oscar; Letelier, Pablo; Weber, Helga; Castillo, Jonathan; Roa Strauch, Juan Carlos Enrique
  • Thumbnail Image
    Item
    Environmental and Lifestyle Risk Factors in the Carcinogenesis of Gallbladder Cancer
    (2022) Pérez Moreno, Pablo; Riquelme, Ismael; García Cañete, Patricia; Brebi, Priscilla; Roa, Juan Carlos
    Gallbladder cancer (GBC) is an aggressive neoplasm that in an early stage is generally asymptomatic and, in most cases, is diagnosed in advanced stages with a very low life expectancy because there is no curative treatment. Therefore, understanding the early carcinogenic mechanisms of this pathology is crucial to proposing preventive strategies for this cancer. The main risk factor is the presence of gallstones, which are associated with some environmental factors such as a sedentary lifestyle and a high-fat diet. Other risk factors such as autoimmune disorders and bacterial, parasitic and fungal infections have also been described. All these factors can generate a long-term inflammatory state characterized by the persistent activation of the immune system, the frequent release of pro-inflammatory cytokines, and the constant production of reactive oxygen species that result in a chronic damage/repair cycle, subsequently inducing the loss of the normal architecture of the gallbladder mucosa that leads to the development of GBC. This review addresses how the different risk factors could promote a chronic inflammatory state essential to the development of gallbladder carcinogenesis, which will make it possible to define some strategies such as anti-inflammatory drugs or public health proposals in the prevention of GBC.
  • No Thumbnail Available
    Item
    Epigallocatechin Gallate Enhances MAL-PDT Cytotoxic Effect on PDT-Resistant Skin Cancer Squamous Cells
    (2020) Leon, Daniela; Buchegger, Kurt; Silva, Ramon; Riquelme, Ismael; Viscarra, Tamara; Mora-Lagos, Barbara; Zanella, Louise; Schafer, Fabiola; Kurachi, Cristina; Roa, Juan Carlos; Ili, Carmen; Brebi, Priscilla
    Photodynamic therapy (PDT) has been used to treat certain types of non-melanoma skin cancer with promising results. However, some skin lesions have not fully responded to this treatment, suggesting a potential PDT-resistant phenotype. Therefore, novel therapeutic alternatives must be identified that improve PDT in resistant skin cancer. In this study, we analyzed the cell viability, intracellular protoporphyrin IX (PpIX) content and subcellular localization, proliferation profile, cell death, reactive oxygen species (ROS) detection and relative gene expression in PDT-resistant HSC-1 cells. PDT-resistant HSC-1 cells show a low quantity of protoporphyrin IX and low levels of ROS, and thus a low rate of death cell. Furthermore, the resistant phenotype showed a downregulation of HSPB1, SLC15A2, FECH, SOD2 and an upregulation of HMBS and BIRC5 genes. On the other hand, epigallocatechin gallate catechin enhanced the MAL-PDT effect, increasing levels of protoporphyrin IX and ROS, and killing 100% of resistant cells. The resistant MAL-PDT model of skin cancer squamous cells (HSC-1) is a reliable and useful tool to understand PDT cytotoxicity and cellular response. These resistant cells were successfully sensitized with epigallocatechin gallate catechin. The in vitro epigallocatechin gallate catechin effect as an enhancer of MAL-PDT in resistant cells is promising in the treatment of difficult skin cancer lesions.