Publications by authors named "N Zambetti"

Multiple Ras proteins, including N-Ras, depend on a palmitoylation/depalmitoylation cycle to regulate their subcellular trafficking and oncogenicity. General lipase inhibitors such as Palmostatin M (Palm M) block N-Ras depalmitoylation, but lack specificity and target several enzymes displaying depalmitoylase activity. Here, we describe ABD957, a potent and selective covalent inhibitor of the ABHD17 family of depalmitoylases, and show that this compound impairs N-Ras depalmitoylation in human acute myeloid leukemia (AML) cells.

View Article and Find Full Text PDF

The outcome of kidney transplant patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is still unclear. Here we describe the clinical characteristics, disease outcome, and risk factors for acute respiratory distress syndrome (ARDS) and death of a cohort of 53 kidney transplant patients with coronavirus disease 2019 (COVID-19). Eight of 53 have been handled as outpatients because of mild disease, on average with immunosuppression reduction and the addition of hydroxychloroquine and azithromycin; no patients required admission, developed ARDS, or died.

View Article and Find Full Text PDF

The outcome of SARS-CoV2 infection in patients who have received a kidney allograft and are being treated with immunosuppression is unclear. We describe 20 kidney transplant recipients (median age 59 years [inter quartile range 51-64 years], median age of transplant 13 years [9-20 years], baseline eGFR 36.5 [23-47.

View Article and Find Full Text PDF

Oncogenic RAS mutations pose substantial challenges for rational drug discovery. Sequence variations within the hypervariable region of Ras isoforms underlie differential posttranslational modification and subcellular trafficking, potentially resulting in selective vulnerabilities. Specifically, inhibiting the palmitoylation/depalmitoylation cycle is an appealing strategy for treating NRAS mutant cancers, particularly as normal tissues would retain K-Ras4b function for physiologic signaling.

View Article and Find Full Text PDF

Mesenchymal niche cells may drive tissue failure and malignant transformation in the hematopoietic system, but the underlying molecular mechanisms and relevance to human disease remain poorly defined. Here, we show that perturbation of mesenchymal cells in a mouse model of the pre-leukemic disorder Shwachman-Diamond syndrome (SDS) induces mitochondrial dysfunction, oxidative stress, and activation of DNA damage responses in hematopoietic stem and progenitor cells. Massive parallel RNA sequencing of highly purified mesenchymal cells in the SDS mouse model and a range of human pre-leukemic syndromes identified p53-S100A8/9-TLR inflammatory signaling as a common driving mechanism of genotoxic stress.

View Article and Find Full Text PDF