Mice lacking NF-κB1 exhibit marked DNA damage responses and more severe gastric pathology in response to intraperitoneal tamoxifen administration

miR-21 and miR-146a: The microRNAs of inflammaging and age-related diseases

The first paper on "inflammaging" published in 2001 paved the way for a unifying theory on how and why aging turns out to be the main risk factor for the development of the most common age-related diseases (ARDs). The most exciting challenge on this topic was explaining how systemic inflammation steeps up with age and why it shows different rates among individuals of the same chronological age. The "epigenetic revolution" in the past twenty years conveyed that the assessment of the individual genetic make-up is not enough to depict the trajectories of age-related inflammation. Accordingly, others and we have been focusing on the role of non-coding RNA, i.e. microRNAs (miRNAs), in inflammaging. The results obtained in the latest 10 years underpinned the key role of a miRNA subset that we have called inflammamiRs, owing to their ability to master (NF-κB)-driven inflammatory pathways. In this review, we will focus on two inflammamiRs, i.e. miR-21-5p and miR-146a-5p, which target a variety of molecules belonging to the NF-κB/NLRP3 pathways. The interplay between miR-146a-5p and IL-6 in the context of aging and ARDs will also be highlighted. We will also provide the most relevant evidence suggesting that circulating inflammamiRs, along with IL-6, can measure the degree of inflammaging.

Combining multi-dimensional data to identify a key signature (gene and miRNA) of cisplatin-resistant gastric cancer

Gastric cancer (GC) is one of the most lethal malignant tumors; the resistance of this type of tumor is the main source of GC treatment failure. In this study, we used bioinformatics analysis to verify differences in resistant GCs and identify an effective method for reversing drug resistance in GC. Microarray data [gene and microRNA (miRNA)] were analyzed using GEO2R software, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were applied to further enrich the genetic data. miRNA-gene interactions were determined using Cytoscape (v.3.5.1). Online software was used to analyze protein interactions and predict network structure. The Cancer Genome Atlas (TCGA) database was used to verify the expression levels of genes in GC resistance. miR-604 expression levels were verified by real-time PCR in GC cell lines. We screened 3981 GC resistance-associated genes and 244 miRNAs using bioinformatics methods. Six hub genes were identified and verified in the TCGA database, including five up-regulated genes, POLR2L, POLR2C, POLR2F, APRT, and LMAN2, and a down-regulated gene, NFKB2. The up-regulated genes POLR2L, POLR2C, APRT, and LMAN2 interact with miR-604; therefore, we focused on miR-604, which has low expression in drug-resistant GC. The results of this study indicate that through bioinformatics technologies, we have determined the hub genes and hub miRNAs related to drug resistance in GC. Among them, miR-604 could become a new indicator in the diagnosis of drug-resistant GC and may be used to investigate the pathogenesis of resistance in GC.

Regenerative proliferation of differentiated cells by mTORC1-dependent paligenosis

In 1900, Adami speculated that a sequence of context-independent energetic and structural changes governed the reversion of differentiated cells to a proliferative, regenerative state. Accordingly, we show here that differentiated cells in diverse organs become proliferative via a shared program. Metaplasia-inducing injury caused both gastric chief and pancreatic acinar cells to decrease mTORC1 activity and massively upregulate lysosomes/autophagosomes; then increase damage associated metaplastic genes such as Sox9; and finally reactivate mTORC1 and re-enter the cell cycle. Blocking mTORC1 permitted autophagy and metaplastic gene induction but blocked cell cycle re-entry at S-phase. In kidney and liver regeneration and in human gastric metaplasia, mTORC1 also correlated with proliferation. In lysosome-defective Gnptab-/- mice, both metaplasia-associated gene expression changes and mTORC1-mediated proliferation were deficient in pancreas and stomach. Our findings indicate differentiated cells become proliferative using a sequential program with intervening checkpoints: (i) differentiated cell structure degradation; (ii) metaplasia- or progenitor-associated gene induction; (iii) cell cycle re-entry. We propose this program, which we term "paligenosis", is a fundamental process, like apoptosis, available to differentiated cells to fuel regeneration following injury.