An HMGA2-p62-ERα axis regulates uterine leiomyomas proliferation

HMGA2 promotes cancer metastasis by regulating epithelial-mesenchymal transition

Epithelial-mesenchymal transition (EMT) is a complex physiological process that transforms polarized epithelial cells into moving mesenchymal cells. Dysfunction of EMT promotes the invasion and metastasis of cancer. The architectural transcription factor high mobility group AT-hook 2 (HMGA2) is highly overexpressed in various types of cancer (e.g., colorectal cancer, liver cancer, breast cancer, uterine leiomyomas) and significantly correlated with poor survival rates. Evidence indicated that HMGA2 overexpression markedly decreased the expression of epithelial marker E-cadherin (CDH1) and increased that of vimentin (VIM), Snail, N-cadherin (CDH2), and zinc finger E-box binding homeobox 1 (ZEB1) by targeting the transforming growth factor beta/SMAD (TGFβ/SMAD), mitogen-activated protein kinase (MAPK), and WNT/beta-catenin (WNT/β-catenin) signaling pathways. Furthermore, a new class of non-coding RNAs (miRNAs, circular RNAs, and long non-coding RNAs) plays an essential role in the process of HMGA2-induced metastasis and invasion of cancer by accelerating the EMT process. In this review, we discuss alterations in the expression of HMGA2 in various types of cancer. Furthermore, we highlight the role of HMGA2-induced EMT in promoting tumor growth, migration, and invasion. More importantly, we discuss extensively the mechanism through which HMGA2 regulates the EMT process and invasion in most cancers, including signaling pathways and the interacting RNA signaling axis. Thus, the elucidation of molecular mechanisms that underlie the effects of HMGA2 on cancer invasion and patient survival by mediating EMT may offer new therapeutic methods for preventing cancer progression.

Non-Coding RNAs Modulating Estrogen Signaling and Response to Endocrine Therapy in Breast Cancer

The largest part of human DNA is transcribed into RNA that does not code for proteins. These non-coding RNAs (ncRNAs) are key regulators of protein-coding gene expression and have been shown to play important roles in health, disease and therapy response. Today, endocrine therapy of ERα-positive breast cancer (BC) is a successful treatment approach, but resistance to this therapy is a major clinical problem. Therefore, a deeper understanding of resistance mechanisms is important to overcome this resistance. An increasing amount of evidence demonstrate that ncRNAs affect the response to endocrine therapy. Thus, ncRNAs are considered versatile biomarkers to predict or monitor therapy response. In this review article, we intend to give a summary and update on the effects of microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) on estrogen signaling in BC cells, this pathway being the target of endocrine therapy, and their role in therapy resistance. For this purpose, we reviewed articles on these topics listed in the PubMed database. Finally, we provide an assessment regarding the clinical use of these ncRNA types, particularly their circulating forms, as predictive BC biomarkers and their potential role as therapy targets to overcome endocrine resistance.

An autophagy-related diagnostic biomarker for uterine fibroids: FOS

Uterine fibroids (UFs) are the most common benign gynecologic tumors in reproductive-aged women. The typical diagnostic strategies of UFs are transvaginal ultrasonography and pathological feature, while molecular biomarkers are considered conventional options in the assessment of the origin and development of UFs in recent years. Here, we extracted the differential expression genes (DEGs) and differential DNA methylation genes (DMGs) of UFs from the Gene Expression Omnibus (GEO) database, GSE64763, GSE120854, GSE45188, and GSE45187. 167 DEGs with aberrant DNA methylation were identified, and further Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) were performed by the relevant R package. We next discerned 2 hub genes (FOS, and TNFSF10) with autophagy involvement by overlapping 167 DEGs and 232 autophagic regulators from Human Autophagy Database. FOS was identified as the most crucial gene through the Protein-Protein Interactions (PPI) network with the correlation of the immune scores. Moreover, the down-regulated expression of FOS in UFs tissue at both mRNA and protein levels was validated by RT-qPCR and immunohistochemistry respectively. The area under the ROC curve (AUC) of FOS was 0.856, with a sensitivity of 86.2% and a specificity of 73.9%. Overall, we explored the possible biomarker of UFs undergoing DNA-methylated autophagy and provided clinicians with a comprehensive assessment of UFs.

Stem Cell Growth and Differentiation in Organ Culture: New Insights for Uterine Fibroid Treatment

Organ culture allows for the understanding of normal and tumor cell biology, and tissues generally remain viable for 5–7 days. Strikingly, we determined that myometrial and MED12 mutant leiomyoma cells repopulated cell-depleted tissue slices after 20 days of culture. Using immunofluorescence and quantitative PCR of stem cell and undifferentiated cell markers, we observed clusters of CD49b⁺ cells in tumor slices. CD49b⁺ cells, however, were sparsely detected in the myometrial slices. Almost all LM cells strongly expressed Ki67, while only a few myometrial cells were stained for this proliferation marker. The CD73 marker was expressed only in tumor cells, whereas the mesenchymal stem cell receptor KIT was detected only in normal cells. HMGA2 and CD24 showed broader expression patterns and higher signal intensity in leiomyoma than in myometrial cells. In this study, we propose that activating CD49b⁺ stem cells in myometrium leads to asymmetrical division, giving rise to transit-amplifying KIT⁺ cells that differentiate to smooth muscle cells. On the contrary, activated leiomyoma CD49b⁺ cells symmetrically divide to form clusters of stem cells that divide and differentiate to smooth muscle cells without losing proliferation ability. In conclusion, normal and mutant stem cells can proliferate and differentiate in long-term organ culture, constituting a helpful platform for novel therapeutic discovery.

Sex Influences Age-Related Changes in Natural Antibodies and CD5+ B-1 Cells

Natural Abs are primarily produced by B-1 cells and are essential for protection against Streptococcus pneumoniae The incidence and mortality rate for pneumococcal infection increases dramatically after age 65, disproportionately affecting males in both human and murine systems. To date, there is a significant gap in our understanding of the relationship among sex, aging, natural IgM efficacy, and the natural IgM repertoire. Our investigation demonstrates that the protective capacity of serum IgM against pneumococcal infection is maintained in IgM obtained from aged female mice but absent in IgM from aged male mice. To understand this difference in protective capacity, we examined serum Ig, discovering that the protective change was not associated with shifts in levels of phosphorylcholine (PC)- or pneumococcal capsular polysaccharide serotype 3-specific IgM. Interestingly, we observed that aged females have an increase in the total number of CD5⁺ B-1 cells, higher serum IL-5 levels, and a larger percentage of aged female CD5⁺ B-1 cells that express CD86 as compared with aged males. Furthermore, single-cell IgM repertoire analysis from peritoneal PC⁺, splenic PC⁺, and bone marrow CD5⁺ B-1 cell subsets demonstrated greater diversity with age and a higher level of germline status in female mice than previously observed in studies of aged male mice. Aged female CD5⁺ B-1 cells also expressed higher levels of transcripts associated with cell activity and self-renewal, such as Nanog and Hmga2 Taken together, these data indicate that females maintain a more diverse and active CD5⁺ B-1 cell pool and natural IgM repertoire, which has implications for sex-related susceptibility to infection and disease.

Molecular and Cellular Insights into the Development of Uterine Fibroids

Uterine leiomyomas represent the most common benign gynecologic tumor. These hormone-dependent smooth-muscle formations occur with an estimated prevalence of ~70% among women of reproductive age and cause symptoms including pain, abnormal uterine bleeding, infertility, and recurrent abortion. Despite the prevalence and public health impact of uterine leiomyomas, available treatments remain limited. Among the potential causes of leiomyomas, early hormonal exposure during periods of development may result in developmental reprogramming via epigenetic changes that persist in adulthood, leading to disease onset or progression. Recent developments in unbiased high-throughput sequencing technology enable powerful approaches to detect driver mutations, yielding new insights into the genomic instability of leiomyomas. Current data also suggest that each leiomyoma originates from the clonal expansion of a single transformed somatic stem cell of the myometrium. In this review, we propose an integrated cellular and molecular view of the origins of leiomyomas, as well as paradigm-shifting studies that will lead to better understanding and the future development of non-surgical treatments for these highly frequent tumors.

Exosomes derived from natural killer cells inhibit hepatic stellate cell activation and liver fibrosis

Activation of hepatic stellate cells (HSCs) is a prominent driver of liver fibrosis. This study was designed to investigate the effect of exosomes derived from natural killer (NK) cells on HSC activation and liver fibrosis. The exosomes were isolated from NK-92MI cells (NK-Exo) and identified by transmission electron microscopy, nanoparticle tracking analysis, and western blot. Then NK-Exo was administered into TGF-β1-treated LX-2 cells (human HSC line) and mice with CCl₄-induced liver fibrosis. LX-2 cell proliferation was determined by CCK-8 assay. The levels of α-SMA and CoL1A1 were measured by qRT-PCR and western blot to evaluate HSC activation. Serum levels of AST and ALT were measured. Hematoxylin-eosin, Masson staining, and Sirius Red staining were performed to assess the pathological changes and collagen deposition. Cell supernatant derived from NK-92MI cells inhibited TGF-β1-induced HSC proliferation and activation in LX-2 cells, and this effect was counteracted by the exosome inhibitor GW4869. Further assays confirmed that NK-Exo treatment significantly inhibited TGF-β1-induced HSC proliferation and activation. Moreover, NK-Exo administration alleviated CCl₄-induced liver fibrosis in mice. NK-Exo inhibited TGF-β1-induced HSC activation and CCl₄-induced liver fibrosis.