BACKGROUND: The adaptation of the redox system and bioenergetics is a major factor contributing to cancer metabolism. Redox therapy is promising but still requires molecular studies that consider the Show more
BACKGROUND: The adaptation of the redox system and bioenergetics is a major factor contributing to cancer metabolism. Redox therapy is promising but still requires molecular studies that consider the reactive species interactome (RSI) concept, which integrates reactive oxygen, nitrogen, sulfur, carbonyl species, and redox enzymes. Our aim was to decipher the role of the RSI in glioblastoma (GBM), including by challenging the RSI with the MnTBAP redox agent.
METHODS: The effects of MnTBAP on the redox system and bioenergetics were investigated on several GBM models, namely in vitro 2D culture, in vitro 3D culture with two human GBM tumoroids, and in vivo preclinical model, which included male and female comparisons.
RESULTS: We show - for the first time - that MnTBAP represses the sulfide:quinone oxidoreductase (SQOR) involved in the sulfur metabolism and bioenergetics, and targets the RSI through the sulfido-redox system. Through in vitro silencing and overexpression approaches, we also demonstrate that SQOR contributed to GBM cell growth and that its decrease is involved in the molecular effect of MnTBAP. Consequently, MnTBAP induces a switch between apoptosis, uncontrolled necrosis, and ferroptosis depending on the glioblastoma models.
CONCLUSION: Our findings represent the next step in establishing a better understanding of redox biology in the context of GBM. Show less
Cell death triggered by photodynamic therapy can occur through different mechanisms: apoptosis, necrosis or autophagy. However, recent studies have demonstrated the existence of other mechanisms with Show more
Cell death triggered by photodynamic therapy can occur through different mechanisms: apoptosis, necrosis or autophagy. However, recent studies have demonstrated the existence of other mechanisms with characteristics of both necrosis and apoptosis. These new cell death pathways, collectively termed regulated necrosis, include a variety of processes triggered by different stimuli. In this study, we evaluated the cell death mechanism induced by photodynamic treatments with two photosensitizers, meso-tetrakis (4-carboxyphenyl) porphyrin sodium salt (Na-H2TCPP) and its zinc derivative Na-ZnTCPP, in two human breast epithelial cell lines, a non-tumoral (MCF-10A) and a tumoral one (SKBR-3). Viability assays showed that photodynamic treatments with both photosensitizers induced a reduction in cell viability in a concentration-dependent manner and no dark toxicity was observed. The cell death mechanisms triggered were evaluated by several assays and cell line-dependent results were found. Most SKBR-3 cells died by either necrosis or apoptosis. By contrast, in MCF-10A cells, necrotic cells and another cell population with characteristics of both necrosis and apoptosis were predominant. In this latter population, cell death was PARP-dependent and translocation of AIF to the nucleus was observed in some cells. These characteristics are related with parthanatos, being the first evidence of this type of regulated necrosis in the field of photodynamic therapy. Show less
AbstractCell death triggered by photodynamic therapy can occur through different mechanisms: apoptosis, necrosis or autophagy. However, recent studies have demonstrated the existence of other mechanis Show more
AbstractCell death triggered by photodynamic therapy can occur through different mechanisms: apoptosis, necrosis or autophagy. However, recent studies have demonstrated the existence of other mechanisms with characteristics of both necrosis and apoptosis. These new cell death pathways, collectively termed regulated necrosis, include a variety of processes triggered by different stimuli. In this study, we evaluated the cell death mechanism induced by photodynamic treatments with two photosensitizers, meso-tetrakis (4-carboxyphenyl) porphyrin sodium salt (Na-H2TCPP) and its zinc derivative Na-ZnTCPP, in two human breast epithelial cell lines, a non-tumoral (MCF-10A) and a tumoral one (SKBR-3). Viability assays showed that photodynamic treatments with both photosensitizers induced a reduction in cell viability in a concentration-dependent manner and no dark toxicity was observed. The cell death mechanisms triggered were evaluated by several assays and cell line-dependent results were found. Most SKBR-3 cells died by either necrosis or apoptosis. By contrast, in MCF-10A cells, necrotic cells and another cell population with characteristics of both necrosis and apoptosis were predominant. In this latter population, cell death was PARP-dependent and translocation of AIF to the nucleus was observed in some cells. These characteristics are related with parthanatos, being the first evidence of this type of regulated necrosis in the field of photodynamic therapy. Show less