Project description:The outbreak-causing monkeypox virus of 2022 (2022 MPXV) is classified as a clade IIb strain and phylogenetically distinct from prior endemic MPXV strains (clades I or IIa), suggesting that its virological properties may also differ. Here, we used human keratinocytes and induced pluripotent stem cell-derived colon organoids to examine the efficiency of viral growth in these cells and the MPXV infection-mediated host responses. MPXV replication was much more productive in keratinocytes than in colon organoids. We observed that MPXV infections, regardless of strain, caused cellular dysfunction and mitochondrial damage in keratinocytes. Notably, a significant increase in the expression of hypoxia-related genes was observed specifically in 2022 MPXV-infected keratinocytes. Our comparison of virological features between 2022 MPXV and prior endemic MPXV strains revealed signaling pathways potentially involved with the cellular damages caused by MPXV infections and highlights host vulnerabilities that could be utilized as protective therapeutic strategies against human mpox in the future.
Project description:The World Health Organization Classification of Hematolymphoid Tumors (WHO) and the International Consensus Classification (ICC) of 2022 introduced major changes to the definition of CMML. To assess qualitative and quantitative implications for patient care, we started with 3,311 established CMML cases (according to WHO 2017 criteria) and included also 2,130 oligomonocytosis cases fulfilling the new CMML diagnostic criteria. Applying both classification systems from 2022, 356 and 241 of oligomonocytosis cases were newly classified as myelodysplastic (MD)-CMML (WHO and ICC 2022, respectively), most of which were diagnosed as MDS according to WHO 2017. Importantly, 1.5 times more oligomonocytosis cases were classified as CMML according to WHO 2022 than based on ICC, due to different diagnostic criteria. Genetic analyses of the newly classified CMML cases showed a distinct mutational profile with strong enrichment of MDS-typical alterations, resulting in a transcriptional subgroup separated from established MD- and myeloproliferative (MP)-CMML. Despite a different cytogenetic, molecular, immunophenotypic, and transcriptional landscape, no differences in overall survival were found between newly classified and established MD-CMML cases. To the best of our knowledge, this study represents the most comprehensive analysis of routine CMML cases to date, both in terms of clinical characterization and transcriptomic analysis, placing newly classified CMML cases on a disease continuum between MDS and previously established CMML.
Project description:Isoniazid (INH) is the first-line anti-tuberculosis drug used for nearly seventy years. Metabolites of INH showed hepatotoxicity in human and tumorigenicity in rodents. However, mechanism underlying the side effects of INH is elusive. Histone acylation is known to be modulated by intracellular metabolites. Here, we report INH and its metabolites induces a novel post-translational modification (PTM) on histones, the lysine isonicotinylation (Kinic), also called 4-picolinylation, in cells and mice. INH functions as a donor to promote biosynthesis of isonicotinyl-CoA that is used for a co-factor of intracellular isonicotinylation reaction. Twenty-six isonicotinylation sites were identified on histones in HepG2 cells by mass spectrometry. Acetyltransferases CREB-binding protein (CBP) and P300 were found to catalyze histone Kinic, whilst histone deacetylase HDAC3 functions as a deisonicotinylase. MNase sensitivity assay and RNA-seq analysis showed that histone Kinic relaxes chromatin structure and promotes gene transcription. Importantly, INH-mediated histone Kinic upregulates PIK3R1 gene expression and activates PI3K/Akt/mTOR signaling pathway in liver cancer cells, linking INH to the tumorigenicity in liver. Further, Kinic was found increased in liver cancer patients with concomitant raised PIK3R1 protein level. In addition, histone Kinic also affects TNF and GABAergic synapse signaling pathways that are closely related to INH-caused side effects. Taken together, we demonstrated that lysine isonicotinylation represents the first histone acylation mark with the pyridine ring that may arise broad biological effects. Therefore, INH-induced isonicotinylation is likely a mechanism accounting for side effects in patients who taking long-term INH for anti-tuberculosis therapy and this modification may also increase cancer risk in human.