@article{VergoteMacarullaHirschetal.2023, author = {Vergote, Ignace and Macarulla, Teresa and Hirsch, Fred R. and Hagemann, Carsten and Miller, David Scott}, title = {Tumor Treating Fields (TTFields) therapy concomitant with taxanes for cancer treatment}, series = {Cancers}, volume = {15}, journal = {Cancers}, number = {3}, issn = {2072-6694}, doi = {10.3390/cancers15030636}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-305007}, year = {2023}, abstract = {Non-small cell lung cancer, ovarian cancer, and pancreatic cancer all present with high morbidity and mortality. Systemic chemotherapies have historically been the cornerstone of standard of care (SOC) regimens for many cancers, but are associated with systemic toxicity. Multimodal treatment combinations can help improve patient outcomes; however, implementation is limited by additive toxicities and potential drug-drug interactions. As such, there is a high unmet need to develop additional therapies to enhance the efficacy of SOC treatments without increasing toxicity. Tumor Treating Fields (TTFields) are electric fields that exert physical forces to disrupt cellular processes critical for cancer cell viability and tumor progression. The therapy is locoregional and is delivered noninvasively to the tumor site via a portable medical device that consists of field generator and arrays that are placed on the patient's skin. As a noninvasive treatment modality, TTFields therapy-related adverse events mainly consist of localized skin reactions, which are manageable with effective acute and prophylactic treatments. TTFields selectively target cancer cells through a multi-mechanistic approach without affecting healthy cells and tissues. Therefore, the application of TTFields therapy concomitant with other cancer treatments may lead to enhanced efficacy, with low risk of further systemic toxicity. In this review, we explore TTFields therapy concomitant with taxanes in both preclinical and clinical settings. The summarized data suggest that TTFields therapy concomitant with taxanes may be beneficial in the treatment of certain cancers.}, language = {en} } @phdthesis{Krenz2023, author = {Krenz, Bastian}, title = {The immune-evasive potential of MYC in pancreatic ductal adenocarcinoma}, doi = {10.25972/OPUS-32590}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-325903}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {Pancreatic ductal adenocarcinoma (PDAC) is predominantly driven by mutations in KRAS and TP53. However, PDAC tumors display deregulated levels of MYC and are a paradigm example for MYC-driven and -addicted tumors. For many years MYC was described as a transcription factor that regulates a pleiotropic number of genes to drive proliferation. Recent work sheds a different light on MYC biology. First, changes in gene expression that come along with the activation of MYC are mild and MYC seems to act more as a factor that reduces stress and increases resilience towards challenges during transcription. Second, MYC is a strong driver of immune evasion in different entities. In this study we depleted MYC in murine PDAC cells and revealed the immune dependent regression of tumors in an orthotope transplant model, as well as the activation of the innate immune system using global expression analysis, immunoblotting and fCLIP. These experiments revealed that endogenous double-stranded RNA is binding as a viral mimicry to Toll-like receptor 3, causing activation of TBK1 and downstream activation of a proimmunogenic transcription program. The regression of tumors upon depletion of MYC is dependent on this pathway since the knockout of TBK1 prevents regression of tumors after depletion of MYC. We can summarize this study in three main findings: First, the dominant and most important function of MYC in tumors is not to drive proliferation but to promote immune evasion and prevent immune-dependent regression of tumors. Second, cells monitor defects or delay in splicing and RNA processing and activate the immune system to clear cells that face problems with co-transcriptional processing. Third, MYC suppresses the activation of the cell-intrinsic innate immune system and shields highly proliferating cells from the recognition by the immune system. To translate this into a therapeutically approach, we replaced the shRNA mediated depletion of MYC by treatment with cardiac glycosides. Upon treatment with cardiac glycosides tumor cells reduce uptake of nutrients, causing a downregulation of MYC translation, inhibition of proliferation, glycolysis and lactate secretion. Lactate is a major reason for immune evasion in solid tumors since it dampens, amongst others, cytotoxic T cells and promotes regulatory T cells. Treatment of mice with cardiac glycosides causes a complete and immune-dependent remission of PDAC tumors in vivo, pointing out that cardiac glycosides have strong proimmunogenic, anti-cancer effects. More detailed analyses will be needed to dissect the full mechanism how cardiac glycosides act on MYC translation and immune evasion in PDAC tumors.}, subject = {Bauchspeicheldr{\"u}senkrebs}, language = {en} }