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Pluvinet, R.

Publications and source records attributed to Pluvinet, R..

3 recordsLinked to original sources

METTL3-mediated m6A modification of DNMT1 enhances ovarian cancer progression

High-grade serous carcinoma (HGSC), the most lethal subtype of ovarian cancer, is often diagnosed at advanced stages owing to its asymptomatic progression and lack of early detection markers. In this study, we identified a critical oncogenic role of the RNA methyltransferase METTL3 and the N6-methyladenosine (m6A) RNA modification pathway in HGSC. Depletion of METTL3 or its binding partner METTL14 impairs ovarian cancer proliferation and tumor progression. Mechanistically, m6A deposition enhances the translation of DNA methyltransferase DNMT1, an epigenetic repressor that silences tumor suppressor genes. Pharmacologic inhibition of DNMT1 led to DNA hypomethylation and upregulation of the tumor suppressors TNFAIP3 and FBXO32. Consistently, METTL3 depletion also increased the expression of these genes supporting a model in which METTL3 sustains oncogenesis by maintaining DNMT1 protein levels and repressing anti-tumor pathways. These findings position METTL3-mediated RNA modifications and DNMT1 as promising therapeutic targets in HGSC.

cancer biology↗

The Multiomics Blueprint of Extreme Human Lifespan

The indexed individual, from now on termed M116, was the worlds oldest verified living person from January 17th 2023 until her passing on August 19th 2024, reaching the age of 117 years and 168 days (https://www.supercentenarian.com/records.html). She was a Caucasian woman born on March 4th 1907 in San Francisco, USA, from Spanish parents and settled in Spain since she was 8. A timeline of her life events and her genealogical tree are shown in Supplementary Fig. 1a-b. Although centenarians are becoming more common in the demographics of human populations, the so-called supercentenarians (over 110 years old) are still a rarity. In Catalonia, the historic nation where M116 lived, the life-expectancy for women is 86 years, so she exceeded the average by more than 30 years (https://www.idescat.cat). In a similar manner to premature aging syndromes, such as Hutchinson-Gilford Progeria and Werner syndrome, which can provide relevant clues about the mechanisms of aging, the study of supercentenarians might also shed light on the pathways involved in lifespan. To unfold the biological properties exhibited by such a remarkable human being, we developed a comprehensive multiomics analysis of her genomic, transcriptomic, metabolomic, proteomic, microbiomic and epigenomic landscapes in different tissues, as depicted in Fig. 1a, comparing the results with those observed in non-supercentenarian populations. The picture that emerges from our study shows that extremely advanced age and poor health are not intrinsically linked and that both processes can be distinguished and dissected at the molecular level. O_FIG O_LINKSMALLFIG WIDTH=156 HEIGHT=200 SRC="FIGDIR/small/639740v1_fig1.gif" ALT="Figure 1"> View larger version (63K): org.highwire.dtl.DTLVardef@1705be6org.highwire.dtl.DTLVardef@1a16e4borg.highwire.dtl.DTLVardef@15005f1org.highwire.dtl.DTLVardef@b6297b_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFig. 1C_FLOATNO Chromosomes and genes.a, Schematic representation of all -omics studied in the supercentenarian. b, Telomeres marked with Cy3 (yellow) in nuclei stained with DAPI (blue) observed in HT-qFISH from M116 and younger womens PBMCs. Scale bars: 20 {micro}m. c, Telomere length (Kb) calculation (left) and percentage of extremely short telomeres (below the 20th percentile) (right) in M116 (orange) using standard curve from samples previously analyzed (black) and control women (blue) (Online Methods). d, Circos plot with chromosomal alterations detected through optical genome mapping in supercentenarian. e, Variants of interest (VOI)-harboring genes found in supercentenarians genomic DNA contributing to immune function, cardiovascular health, neuroprotection, metabolism, and DNA dynamics. f, Significantly enriched functions of VOI-harboring genes in the supercentenarian. g, VOI-harbouring genes significantly contributing to enriched functions. h, VOI-harboring genes found in supercentenarians genomic and mitochondrial DNA contributing to mitochondrial function. i, Mean fluorescence intensity of TMRE (a marker of mitochondrial membrane potential) and SOX (a marker of mitochondrial superoxide ion) in PBMCs from the supercentenarian (orange) and healthy controls across various ages (gray). Unpaired t-test was used to statistically compare M116 to the mean of all control women. *p < 0.05. C_FIG

genomics↗

Targetable Treatment Resistance in Thyroid Cancer with Clonal Hematopoiesis

Anaplastic thyroid cancer (ATC) is a clinically aggressive malignancy with a dismal prognosis. Combined BRAF/MEK inhibition offers significant therapeutic benefit in patients with BRAFV600E-mutant ATCs. However, relapses are common and overall survival remains poor. Compared with differentiated thyroid cancer, a hallmark of ATCs is significant infiltration with myeloid cells, particularly macrophages. ATCs are most common in the aging population, which also has an increased incidence of TET2-mutant clonal hematopoiesis (CH). CH-mutant macrophages have been shown to accelerate CH-associated pathophysiology including atherosclerosis. However, the clinical and mechanistic contribution of CH-mutant clones to solid tumour biology, prognosis and therapeutic response has not been elucidated. Here we show that TET2-mutant CH is enriched in the tumour microenvironment of patients with solid tumours and associated with adverse prognosis in ATC patients. We find that Tet2-mutant macrophages selectively infiltrate mouse BrafV600E-mutant ATC and that their overexpression of Tgf{beta}-family ligands mediates resistance to BRAF/MEK inhibition. Importantly, inhibition of Tgf{beta} signaling restores sensitivity to MAPK pathway inhibition, opening a path for synergistic strategies to improve outcomes of patients with ATCs and concurrent CH.

cancer biology↗