Project description:To investigate the mechanisms of PI3Kα-induced senescence, we performed a gene expression microarray analysis with MCF-10A/H and parental MCF-10A cells.
Project description:We set out to characterize the transcriptional heterogeneity of the senescence program using a large number of whole-transcriptome sequencing datasets generated by us or publicly available. We identify a number of senescence transcriptional signatures associated to specific stresses or cell types. We also merge all the studies to identify and validate the genes that are universally differentially regulated during senescence.
Project description:Uncontrolled accumulation of pulmonary artery smooth muscle cells (PASMC) to the distal pulmonary arterioles (PAs) is one of the major characteristics of pulmonary hypertension (PH). Cellular senescence contributes to aging and lung diseases associated with PH and links to PH progression. However, the mechanism by which cellular senescence controls vascular remodeling in PH is not fully understood. The levels of senescence marker, p16INK4A and senescence-associated β-galactosidase (SA-β-gal) activity are higher in PA endothelial cells (ECs) isolated from idiopathic pulmonary arterial hypertension (IPAH) patients compared to those from healthy individuals. Hypoxia-induced accumulation of α-smooth muscle actin (αSMA)-positive cells to the PAs is attenuated in p16fl/fl-Cdh5(PAC)-CreERT2 (p16iΔEC) mice after tamoxifen induction. We have reported that endothelial TWIST1 mediates hypoxia-induced vascular remodeling by increasing platelet-derived growth factor (PDGFB) expression. Transcriptomic analyses of IPAH patient or hypoxia-induced mouse lung ECs reveal the alteration of senescence-related gene expression and their interaction with TWIST1. Knockdown of p16INK4A attenuates the expression of PDGFB and TWIST1 in IPAH patient PAECs or hypoxia-treated mouse lungs and suppresses accumulation of αSMA–positive cells to the supplemented ECs in the gel implanted on the mouse lungs. Hypoxia-treated mouse lung EC-derived exosomes stimulate DNA synthesis and migration of PASMCs in vitro and in the gel implanted on the mouse lungs, while p16iΔEC mouse lung EC-derived exosomes inhibit the effects. These results suggest that endothelial senescence controls αSMA–positive cell proliferation and migration in PH through TWIST1-PDGFB signaling.
Project description:Cellular senescence is described as an irreversible cell cycle arrest induced in response to various stresses. Senescent cells are characterised by heterogeneous signalling alterations, complex secretory phenotype, known as senescence-associated secretory phenotype (SASP), and diverse transcriptomic profile. With the aim to investigate senescence heterogeneity and identify conserved transctiptomic alterations and universal senescence markers, we performed RNA-seq and multiplex proteomic analysis in proteasome inhibition-induced and stress-induced premature senescence models of HFL1 and BJ human fibroblasts. Our data revealed diverse transcriptomic signatures, but also, 231 common differentially expressed genes related to cell division and ECM remodelling, and enriched pathways that remained conserved among the different models with senescence onset. Moreover, we identified a subset of proteins and validated them in replicative senescent models. These proteins are involved in cell cycle arrest and promote a pro-inflammatory environment in premature and replicative senescence models. We suggest that the simultaneous analysis of p21, p-c-JUN, BCL-xL and survivin in cellular lysates, and IL-8, GM-CSF, GDF-15 and GROa in culture supernatants can provide a powerful tool for the identification and monitoring of senescent cells and can support the assessment of the efficacy of potential senotherapeutic approaches.
Project description:Senescence can be transmitted in a paracrine way from cells undergoing Oncogene Induced Senescence (OIS) to naïve normal cells. We define this phenomenon as “paracrine senescence” We used microarrays to compare the trancriptome of cells undergoing paracrine senescence to the transcriptome of cells suffering OIS to unveil the common signatures defining both events and the similarities between them