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Biology subjects

Pedroso, D.

Publications and source records attributed to Pedroso, D..

4 recordsLinked to original sources

Refined USP25/28 inhibitors with improved selectivity towards c-Myc driven squamous lung cancer cells

The ubiquitin specific protease 28 (USP28) is implicated in tumorigenesis by controlling the turnover of substrates including the oncogene c-MYC and the ubiquitin ligase FBW7. Here, we describe small molecule inhibitors of USP25 and USP28, leading to cancer cell cycle arrest and death. However, genetic deletion of USP25/28 does not replicate this effect. An integrated -omics approach revealed off-target effects for thienopyridine and thienopyrazine carboxamide compounds in protein translation. Chemoproteomics and biochemical analyses suggested binding of such compounds to a region near the ribosome complex polypeptide exit tunnel. Structural analysis of a USP28-inhibitor complex enabled the design of modified USP25/28 inhibitor molecules which minimized translation-related off-target effects. In distinction to earlier compounds, the optimized inhibitors were non-toxic to breast cancer cells yet retained potent anti-proliferative activity in squamous lung carcinoma cells, where USP28 is associated with disease progression. Together, our results demonstrate that refined USP25/28 inhibitors can selectively suppress tumor growth by targeting c-MYC driven pathways, offering a more precise therapeutic strategy for treating squamous lung cancers whilst minimizing undesired cytotoxicity.

cancer biology↗

DNA damage independent inhibition of NF-κB transcription by anthracyclines

Anthracyclines are among the most used and effective anticancer drugs. Their activity has been attributed to DNA double-strand breaks resulting from topoisomerase II poisoning and to eviction of histones from select sites in the genome. Here we show that the extensively used anthracyclines Doxorubicin, Daunorubicin and Epirubicin, decrease the transcription of nuclear factor kappa B (NF-{kappa}B)-dependent gene targets, but not interferon responsive genes. Using an NMR-based structural approach, we demonstrate that anthracyclines disturb the complexes formed between the NF-{kappa}B subunit RelA and its DNA binding sites. The variant anthracyclines Aclarubicin, Doxorubicinone and the newly developed Dimethyl-doxorubicin, which share anticancer properties with the other anthracyclines but do not induce DNA damage, also suppressed inflammation, thus uncoupling DNA damage from the effects on inflammation. These findings have implications for anticancer therapy and for the development of novel anti-inflammatory drugs with limited side effects for life-threatening conditions such as sepsis.

immunology↗

Host-dependent induction of disease tolerance to infection by tetracycline antibiotics

Synergy of resistance and disease tolerance mechanisms is necessary for an effective immune response leading to survival and return to homeostasis when an organism is challenged by infection. Antibiotics are used for their resistance enhancement capabilities by decreasing pathogen load, but several classes have long been known to have beneficial effects that cannot be explained strictly on the basis of their capacity to control the infectious agent. Here we report that tetracycline antibiotics, a class of ribosome-targeting drugs, robustly protects against sepsis by inducing disease tolerance, independently from their direct antibiotic properties. Mechanistically, we find that mitochondrial inhibition of protein synthesis perturbs the electron transfer chain and leads to improved damage repair in the lung and fatty acid oxidation and glucocorticoid sensitivity in the liver. Using a partial and acute deletion of CRIF1 in the liver, a critical mitoribosomal component for protein synthesis, we find that mice are protected against bacterial sepsis, an observation which is phenocopied by the transient inhibition of complex I of ETC by phenformin. Together, we demonstrate that ribosome-targeting antibiotics are beneficial beyond their antibacterial activity and that mitochondrial protein synthesis inhibition leading to ETC perturbation is a novel mechanism for the induction of disease tolerance.

immunology↗

CXCL5-mediated recruitment of neutrophils into the peritoneal cavity of Gdf15-deficient mice protects against abdominal sepsis

Sepsis is a life-threatening organ dysfunction condition caused by a dysregulated host response to an infection. Here we report that the circulating levels of growth-differentiation factor-15 (GDF15) are strongly increased in septic shock patients and correlate with mortality. In mice, we find that peptidoglycan is a potent ligand that signals through the TLR2-Myd88 axis for the secretion of GDF15 and that Gdf15-deficient animals are protected against abdominal sepsis due to increased chemokine CXC ligand 5 (CXCL5)-mediated recruitment of neutrophils into the peritoneum leading to better local bacterial control. Our results identify GDF15 as a potential target to improve sepsis treatment. Its inhibition should increase neutrophil recruitment to the site of infection and consequently lead to better pathogen control and clearance.

immunology↗