Human Cell最新文献

Radiotherapy resistance, is usually caused by enhanced tumor stemness and poses a significant challenge in treating breast cancer (BRCA). In this study, we investigated the molecular regulatory mechanism of radiotherapy sensitivity in BRCA associated with replication factor C4 (RFC4) and insulin-like growth factor 2 mRNA binding protein 2 mRNA Binding Protein 2 (IGF2BP2). RFC4 expression was increased in BRCA cell lines and tissues, and high RFC4 expression in BRCA patients predicted the occurrence of lymphatic metastasis. RFC4-specific short hairpin RNA sequences or RFC4 coding sequences were subsequently cloned and inserted into plasmid vectors to downregulate or upregulate RFC4 expression. Knockdown of RFC4 attenuated stemness, as evidenced by a reduction in sphere formation and the downregulation of CD44 and SOX2. RFC4 silencing inhibited migration and invasion, promoted apoptosis, and improved sensitivity to radiotherapy (4-Gy X-ray). The results were detected by a wound healing assay, a transwell assay, and flow cytometry. The overexpression of RFC4 had the opposite effect on BRCA cells. Like RFC4 expression, IGF2BP2 expression was also increased in the cancer tissues of breast cancer patients. The results of the dual luciferase assay and RIP assay confirmed the binding of IGF2BP2 to the RFC4 mRNA coding sequence. Knockdown of RFC4 eliminated the effects of IGF2BP2 overexpression on increasing cell viability, invasion, the expression of stemness markers and radioresistance, suggesting that the effect of RFC4 on the stemness of BRCA cells was regulated by IGF2BP2. In conclusion, we reported that RFC4, a key regulator of BRCA progression, promoted radioresistance in BRCA and was positively regulated by IGF2BP2.

Propionic acidemia (PA) is a rare autosomal recessive metabolic disorder caused by mutations in the PCCA and PCCB genes, which encode subunits of the mitochondrial enzyme propionyl-CoA carboxylase (PCC). This enzyme deficiency leads to the accumulation of toxic metabolites, resulting in severe metabolic dysfunction. To create ideal in vitro disease models of PA with isogenic controls and provide a robust platform for therapeutic research, we generated two induced pluripotent stem cell (iPSC) lines with knockout (KO) mutations in the PCCA and PCCB genes using CRISPR-Cas9 gene editing in a healthy control iPSC line. The KO iPS cells were successfully established and characterized, confirming the presence of frameshift insertions and deletions in each target gene, as well as the loss of the corresponding transcript, protein expression, and activity. Additionally, the generated iPSC lines exhibit hallmark characteristics of pluripotency, including the potential to differentiate into all three germ layers. Our PCCA and PCCB KO iPSC models provide a valuable tool for studying the molecular mechanisms underlying PA and hold potential for advancing new therapeutic approaches.

We previously reported that high tumoral expression of Toll-like receptor 3 (TLR3) and CXCL10, a member of the CXC chemokine family, was an independent positive prognostic factor in patients with advanced thoracic esophageal squamous cell carcinoma (ESCC). However, the direct relationships between TLR3 and CXCL10 in ESCC cells was not fully understood. Here, we analyzed TLR3 mRNA and protein expression in two ESCC lines (TE8 and KYSE180) and one esophageal adenocarcinoma (EAC) line (OE19). We also assessed the effect of the TLR3 agonist poly(I:C) on production of downstream adapter proteins and cytokines, including CXCL10, and further tested its effects on cell viability and caspase 3/7 activity with and without siRNA-induced knockdown of TLR3 and the TICAM-1 or MAVS adapter protein. Both ESCC lines, but not the EAC line, showed high expression of TLR3 mRNA and protein. TICAM-1 and MAVS were also expressed, and their knockdown suppressed responsiveness to poly(I:C) in the ESCC lines. Poly(I:C) induced strong CXCL10 production, resulting in significantly upregulated caspase3/7 activity and downregulated cell proliferation in both ESCC lines but not the EAC line. The effect of poly(I:C) on CXCL10 production was attenuated after transfecting the cells with siRNAs targeting TICAM-1 or MAVS. TLR3 is thus highly expressed in ESCC cells, where it induces strong CXCL10 production and significantly upregulates caspase3/7 activity and downregulates cell proliferation. TLR3 signaling and the resultant downstream CXCL10 production have the potential to serve as useful prognostic markers and therapeutic targets for the treatment of ESCC.

Myofibroblasts combine features of fibroblasts and smooth muscle cells, and they are reactive cells present under injury conditions. This study was performed to explore the mechanism that methylenetetrahydrofolate dehydrogenase/cyclohydrolase 2 (MTHFD2) mediated m6A modification in sepsis-induced AKI (SAKI) through regulating the collagen accumulation in myofibroblasts. Gene expression microarrays related to SAKI were obtained from the GEO database, and the hub protein involved was screened using PPI. The SAKI mice were induced by cecal ligation and puncture (CLP). MTHFD2 expression was significantly elevated in the kidneys of CLP-induced mice, and SAKI was ameliorated by knocking down MTHFD2 in kidney tissues. MTHFD2 promoted N⁶-methyladenosine (m6A) modification in kidney tissues of CLP-induced mice by increasing the content of methylated donor s-adenosylmethionine (SAM). MTHFD2 enhanced LOX mRNA stability in an m6A modification-dependent manner, thereby promoting its expression. Knockdown of MTHFD2 inhibited collagen accumulation in myofibroblasts, whereas overexpression of LOX accelerated fibrosis and SAKI in mice in the presence of sh-MTHFD2. In conclusion, our results show that MTHFD2 promotes LOX expression in an m6A-dependent manner, thereby mediating SAKI progression.

Osteoarthritis (OA) is a widespread chronic bone and joint disease for which there is currently no effective preventive or therapeutic treatment. Accumulating evidence indicates that circular RNAs (circRNAs), a class of noncoding RNAs, play critical roles in OA. Therefore, in this study, we aimed to reveal an unexplored circTBCK and elucidate its mechanism of action in the pathological process of OA. The different expression of circTBCK was obtained both in vitro and in vivo. In the in vivo model, mice were induced via destabilization of the medial meniscus (DMM) surgery, while in vitro model, mouse cells like primary chondrocytes of newborn mice and ATDC5 cell line were treated with IL-1β treatment (10 ng/mL for 24 h). The level of circTBCK was examined by quantitative real-time polymerase chain reaction (qRT-PCR). After circTBCK was overexpressed or knocked down, IL-1β treatment was performed, and then, chondrocyte viability was detected via a Cell Counting Kit-8 (CCK-8) assay at 0, 24, 48, or 72 h. To assess type II collagen (Collagen II) expression, immunofluorescence (IF) analysis was used. The levels of mRNAs and proteins related to proliferation, the extracellular matrix (ECM) and autophagy were determined by qRT-PCR and Western blotting. Compared with OA treatment, primary chondrocytes with treatment of both circTBCK overexpression and IL-1βincreased the expression of anabolic factors-Collagen II and SRY-box transcription factor 9 (SOX9), proliferation-related molecules-Ki-67 and proliferating cell nuclear antigen (PCNA), and autophagy-related molecules-Microtubule-associated protein 1 light chain 3 (LC3), B-cell lymphoma 1 (Bcl1), and autophagy-related 5 (Atg5) and decreased Sequestosome 1 (SQSTM1 or P62). In contrast, knockdown of circTBCK aggravated the chondrocyte degeneration induced by IL-1β. Overall, our findings suggest that circTBCK, an unexplored circRNA, could regulate autophagy, proliferation, and the extracellular matrix (ECM) to mitigate the development of OA, suggesting a possible target for OA prevention and therapy.

Heart failure is known as the leading cause of mortality and morbidity in adults, not only in USA but worldwide. Since the world's population is aging, the burden of cardiovascular disorders is increasing. Mesenchymal stem/stromal cells (MSCs) from a patient's bone marrow or other tissues have been widely used as the primary source of stem cells for cellular cardiomyoplasty. The incongruencies that exist between various cell-therapy approaches for cardiac diseases could be attributed to variations in cell processing methods, quality of the process, and cell donors. Off-the-shelf preparations of MSCs, enabled by batch processing of the cells and controlled cell processing factories in regulated facilities, may offer opportunities to overcome these problems. In this study, for the first time, we focused on the fetal membranes and childbirth byproducts as a promising source of cells for regenerative medicine. While many studies have described the advantages of cells derived from these organs, their advantage as a source of younger cells has not been sufficiently covered by the literature. Thus, herein, we highlight challenges that may arise from the impairment of the regenerative capacity of MSCs due to donor age and how allograft cells from fetal adnexa can be a promising substitute for the aged patients' stem cells for myocardial regeneration. Moreover, obstacles to the use of off-the-shelf cell-therapy preparations in regenerative medicine are briefly summarized here.

High glucose leads to cellular damage and dysfunction in the retina. Dietary interventions, including the use of ketogenic diets, have been explored for their potential to reduce the adverse effects of hyperglycemia. β-Hydroxybutyrate (BHB), a ketone body, has immune and anti-inflammatory properties. This study aims to investigate whether BHB ameliorates the harmful effects induced by high glucose in ARPE-19 cells, a model of retinal pigment epithelium. We investigated the effects induced by high glucose and/or BHB on viability, migration, colony-forming ability, cell cycle progression and cytokine production. Our data indicate that high glucose significantly reduces the viability of ARPE-19 cells with no significant changes in apoptosis or autophagy, while inducing cell cytostasis. On the other hand, BHB exerts a protective effect on ARPE-19 cells under hyperglycemic conditions improving cell viability and alleviating glucose-induced cell cycle arrest. Additionally, BHB treatment affects the expression of IL-8 and IL-17α, as well as of MCP-1, modulating the inflammatory response, cell migration and wound healing. In conclusion, this study highlights the potential protective role of BHB against the detrimental effects induced by high glucose on ARPE-19 cells. These findings support the use of ketone bodies in mitigating high glucose-induced cellular damage. Future research will be critical to translate these findings to the clinical practice for metabolic diseases.

Extrachromosomal circular DNA (eccDNA) is a fascinating form of genetic material found outside the usual chromosomal DNA in eukaryotic cells, including humans. Since its discovery in the 1960s, eccDNA has been linked to critical roles in cancer progression and age-related diseases. This review thoroughly explores eccDNA, covering its types, how it forms, and its significant impact on diseases, particularly cancer. EccDNA, especially in its extrachromosomal DNA (ecDNA) form, contributes to the genetic diversity of tumour cells, helping them evolve quickly and resist treatments. Beyond cancer, eccDNA is also connected to age-related conditions like Werner syndrome, amyotrophic lateral sclerosis (ALS), and type 2 diabetes mellitus (T2DM), where it may affect genomic stability and disease development. The potential of eccDNA as a biomarker for predicting disease outcomes and as a target for new treatments is also highlighted. This review aims to deepen our understanding of eccDNA and inspire further research into its roles in human health and disease, paving the way for innovative diagnostic and therapeutic approaches.

Keratoconus (KC) is characterised by corneal stromal thinning and irregular astigmatism, resulting in diminution of vision. Underlying aetiology remains poorly understood. Recent evidence suggests dysregulation of oxidative balance and mitochondrial function in KC corneas. Therefore, this study aims to investigate the morphology of mitochondria in the corneal tissues. Twenty patients each diagnosed with KC and age-matched healthy controls were enrolled in this study. Demographic and clinical details were recorded. Corneal tissues were collected and analyzed using hematoxylin and eosin staining and transmission electron microscopy (TEM). Patients were followed up for 6 months. There was a male preponderance (75%) with an average age of 23.05 ± 6.92 years in KC patients. The clinical findings showed a history of eye atopy (65%), frequent eye rubbing (65%), and characteristic KC signs such as Munson's sign (60%) and Vogt striae (60%). The TEM analysis revealed that KC corneal epithelium exhibited numerous degraded mitochondria with dissolved cristae and heterogenous morphology, while healthy controls displayed intact mitochondrial structures. Similarly, the stroma of KC patients showed very few mitochondria with altered morphology, necrotic keratocytes, and loosely packed collagen fibrils. All the cases showed no disease progression on follow up. This is the first study providing the novel insights into the ultrastructural changes of mitochondria in epithelium and stromal layers of moderate and advanced cases of KC. This emphasises the significant mitochondrial degradation and morphological abnormalities in the corneal tissues of KC patients, indicating a pivotal role of mitochondrial dysfunction in the pathophysiology of keratoconus.

Age-related macular degeneration (AMD), the leading cause of irreversible vision loss in the US, is on the rise among the elderly. Uncontrolled mitochondria-derived peptide production from mtDNA disruption and 16S or 12S rRNA damage could worsen AMD. Our previous work has shown that Humanin G possesses cytoprotective effects in retinal pigment epithelial (RPE) cells. However, MOTS-c, a highly efficient mitochondrial peptide, has yet to be evaluated on retinal cell survival. In this study, we show that there are differences in effects between wild-type (wt-) and differentiated ARPE19 cells (diff-ARPE19), implying that the cellular differentiation status may influence how cells respond to MOTS-c. MOTS-c has dose-dependent effects on apoptosis, inflammation, and mitochondrial biogenesis in diff-ARPE19 cells. Lower doses (500 nM) have more significant impacts than 5 µM concentrations. In diff-ARPE19 cells, a lower dose of MOTS-c can reduce the negative impact of hypoxia on cellular survival and gene expression, including apoptosis (CASP3, CASP9), mitochondrial biogenesis (TFAM, PGC-1α), and metabolic sensor (AMPK). However, it had no significant effect on ROS levels or NRF1 expression, regardless of MOTS-c dose. Exposing diff-ARPE19 cells to varied MOTS-c dosages before and after therapy in a chemically induced hypoxic environment yields no extra benefits as compared to MOTS-c treatment alone. MOTS-c had different effects on the expression of genes linked with apoptosis, mitochondrial biogenesis, and antioxidant activity in AMD patients versus age-matched control cybrids. The MOTS-c peptide appears to enhance cellular metabolism and regulate gene expression, which could potentially provide therapeutic benefits in AMD.