Browsing by Person "Renner, Olga"

Now showing 1 - 2 of 2

Role of iron and TfR1 in the application of high‑dose ascorbate against pancreatic cancer
(2026) Piotrowsky, Alban; Leischner, Christian; Schmieder, Hendrik; Detert, Katja; Schneider, Kathrin; Schulte, Johanna; Hammerschmidt, Sabrina; Marongiu, Luigi; Renner, Olga; Burkard, Markus; Venturelli, Sascha
Pancreatic cancer remains one of the deadliest tumor diseases with an urgent need for new therapy options. At the same time, the use of high‑dose vitamin C in cancer treatment has been investigated for decades. Despite promising in vitro and in vivo data and initial clinical studies, there is a need for optimization with regard to an ideal treatment regimen and suitable patient population for the use of high‑dose vitamin C. The aim of the present study was to evaluate for the first time the combination of high‑dose vitamin C with the administration of iron in three human pancreatic cancer cell lines and to determine the exact cell death mechanism. While the investigated cell lines showed a high susceptibility to ascorbate treatment, the combination treatment with FeCl3 generally led to a reduction in the ascorbate effect and in the formation of reactive oxygen species. The ascorbate‑induced cell death showed no signs of apoptosis but clear ferroptotic properties. Furthermore, treatment of the tumor cells with FeCl3 was accompanied by reduced expression of TfR1, preventing an increase in the intracellular labile iron pool. The present study provided valuable information on the mechanism of action of high‑dose vitamin C in pancreatic cancer, whereby a combination treatment with ferric iron in the context of tumor therapy is not recommended based on these data.
The therapeutic potential of vitamins A, C, and D in pancreatic cancer
(2025) Piotrowsky, Alban; Burkard, Markus; Schmieder, Hendrik; Venturelli, Sascha; Renner, Olga; Marongiu, Luigi
The pancreatic ductal adenocarcinoma (PDAC) is among the deadliest tumor diseases worldwide. While treatment options have generally become more diverse, little progress has been made in the treatment of PDAC and the median survival time for patients with locally advanced PDAC is between 8.7 and 13.7 months despite treatment. The aim of this review was to explore the therapeutic potential of complementing standard therapy with natural or synthetic forms of vitamins A, C, and D. The therapeutic use of vitamins A, C, and D could be a promising addition to the treatment of PDAC. For all three vitamins and their derivatives, tumor cell-specific cytotoxicity and growth inhibition against PDAC cells has been demonstrated in vitro and in preclinical animal models. While the antitumor effect of vitamin C is probably mainly due to its pro-oxidative effect in supraphysiological concentrations, vitamin A and vitamin D exert their effect by activating nuclear receptors and influencing gene transcription. In addition, there is increasing evidence that vitamin A and vitamin D influence the tumor stroma, making the tumor tissue more accessible to other therapeutic agents. Based on these promising findings, there is a high urgency to investigate vitamins A, C, and D in a clinical context as a supplement to standard therapy in PDAC. Further studies are needed to better understand the exact mechanism of action of the individual compounds and to develop the best possible treatment regimen. This could contribute to the long-awaited progress in the treatment of this highly lethal tumor entity.