Growth Of Epithelial Cells Research Articles

A suture-free, shape self-adaptive and bioactive PEG-Lysozyme implant for Corneal stroma defect repair and rapid vision restoration.

Corneal transplantation is a prevailing treatment to repair injured cornea and restore vision but faces the limitation of donor tissue shortage clinically. In addition, suturing-needed transplantation potentially causes postoperative complications. Herein, we design a PEG-Lysozyme injective hydrogel as a suture-free, shape self-adaptive, bioactive implant for corneal stroma defect repair. This implant experiences a sol-gel phase transition via an in situ amidation reaction between 4-arm-PEG-NHS and lysozyme. The physicochemical properties of PEG-Lysozyme can be tuned by the components ratio, which confers the implant mimetic corneal modulus and provides tissue adhesion to endure increased intraocular pressure. In vitro tests prove that the implant is beneficial to Human corneal epithelial cells growth and migration due to the bioactivity of lysozyme. Rabbit lamellar keratoplasty experiment demonstrates that the hydrogel can be filled into defect to form a shape-adaptive implant adhered to native stroma. The implant promotes epithelialization and stroma integrity, recovering the topology of injured cornea to normal. A newly established animal forging behavior test prove a rapid visual restoration of rabbits when use implant in a suture free manner. In general, this work provides a promising preclinical practice by applicating a self-curing, shape self-adaptive and bioactive PEG-Lysozyme implant for suture-free stroma repair.

Vγ9+Vδ2+ T cell control of Listeria monocytogenes growth in infected epithelial cells requires butyrophilin 3A genes

Intracellular bacteria produce antigens, which serve as potent activators of γδ T cells. Phosphoantigens are presented via a complex of butyrophilins (BTN) to signal infection to human Vγ9+Vδ2+ T cells. Here, we established an in vitro system allowing for studies of Vγ9+Vδ2+ T cell activity in coculture with epithelial cells infected with the intracellular bacterial pathogen Listeria monocytogenes. We report that the Vγ9+Vδ2+ T cells efficiently control L. monocytogenes growth in such cultures. This effector function requires the expression of members of the BTN3A family on epithelial cells. Specifically, we observed a BTN3A1-independent BTN3A3 activity to present antigen to Vγ9+Vδ2+ T cells. Since BTN3A1 is the only BTN3A associated with phosphoantigen presentation, our study suggests that BTN3A3 may present different classes of antigens to mediate Vγ9+Vδ2+ T cell effector function against L. monocytogenes-infected epithelia.

Molecular Action of Tamoxifen in the Ovaries of Rats with Mammary Neoplasia

Tamoxifen (TAM) is a drug commonly used in patients with breast cancer. The anticancer effect of TAM occurs via its ability to antagonize estrogen-dependent growth of mammary epithelial cells. Previously, we demonstrated that TAM prevented the chemotherapy-induced loss of ovarian follicular reserves in both cancer-free rats and rats with cancer. Such follicular loss is a main cause of infertility in young women treated for cancer. The current study was undertaken to discover the molecules and intracellular pathways involved in the action of TAM in the ovaries of rats with mammary tumors. To meet this goal we used transcriptomic (RNA-Seq) and proteomic (2D-DIGE/MS) approaches. TAM inhibited the expression of genes and lncRNAs involved in ovarian steroidogenesis. Moreover, TAM altered the expression of genes related to primordial follicle activation or arrest. In addition, proteomic screening indicated the importance of basic metabolic processes in the ovarian actions of TAM. Although simple extrapolation of these data to humans is not possible, the results of this study emphasize the need to explore the ability of TAM to affect ovarian function in women undergoing cancer treatment.

PSI-19 A Saccharomyces Cerevisiae-Derived Postbiotic Stimulates in Vitro Volatile Fatty Acid Production and Influences Hindgut Microbial Population Characteristics

Abstract Horses rely on volatile fatty acids (VFA) to provide a source of energy and fermentative end-products for their health and performance. Improvement in VFA production, has been associated in various species with improved feed conversion and availability of nutrients necessary to maintain epithelial cell growth, blood flow, and the normal secretory and absorptive functions of the intestine and positive changes in the microbial ecology of the gut. In this study, we characterized the effect of a dietary Saccharomyces cerevisiae fermentation postbiotic (SCFP; Diamond V, Cedar Rapids, IA) using an in vitro equine intestinal model to estimate the effects on VFA production and microbiome changes in the horse hindgut. Treatments contained inoculated medium containing a predigested blend of alfalfa and timothy hay substrate and a dilution of fresh equine excreta. The test article (SCFP) was evaluated at 150 mg (TEC) and 225 mg (TECP), in addition to a negative control containing inoculated medium alone, and the positive control containing inulin. The full array of treatments and replicates were incubated anaerobically at 37.2 C for 24 h. VFA concentrations were analyzed by gas chromatography and the microbiome was characterized through shotgun sequencing. Both levels of SCFP supported greater (P < 0.05) acetate, propionate, butyrate, and total VFA production versus the negative control. Greater production of acetate, propionate, butyrate and total VFA was observed for TECP compared with the positive control (P < 0.05). Between the two SCFP treatments, TECP promoted more acetate, propionate and total VFA (P < 0.01), and 18.3% more butyrate than TEC. Significant microbiome changes were also observed, with TEC and TECP promoting greater microbiome diversity (P < 0.05) compared with both negative and positive controls. Compared with the negative control, both levels of SCFP influenced an increased abundance (P < 0.05) of lactic acid producers (Veillonella), butyrate producers (Butyricicoccus, Anaerobutyricum), and an increased abundance of multiple Bacteroides species, all known for their enrichment of carbohydrate-degrading enzymes. Interestingly, our data show a distinct effect of inulin in microbial communities by promoting an increased abundance of Streptococcus species. This study provides evidence that a SCFP can stimulate VFA production, and this effect is incremental with the level of administration which could potentially provide gut health benefits in horses.

Culturing Limbal Epithelial Cells of Long-term Stored Corneal Donors (Organ Culture) In Vitro - A Stepwise Linear Regression Algorithm.

To assess various potential factors on human limbal epithelial cell (LEC) outgrowth in vitro using corneal donor tissue following long-term storage (organ culture) and a stepwise linear regression algorithm. Of 215 donors, 304 corneoscleral rings were used for our experiments. For digestion of the limbal tissue and isolation of the limbal epithelial cells, the tissue pieces were incubated with 4.0 mg/mL collagenase A at 37 °C with 95% relative humidity and a 5% CO2 atmosphere overnight. Thereafter, limbal epithelial cells were separated from limbal keratocytes using a 20-µm CellTricks filter. The separated human LECs were cultured in keratinocyte serum-free medium medium, 1% penicillin/streptomycin (P/S), 0.02% epidermal growth factor (EGF), and 0.3% bovine pituitary extract (BPE). The potential effect of donor age (covariate), postmortem time (covariate), medium time (covariate), size of the used corneoscleral ring (360°, 270°180°, 120°, 90°, less than 90°) (covariate), endothelial cell density (ECD) (covariate), gender (factor), number of culture medium changes during organ culture (factor), and origin of the donor (donating institution and storing institution, factor) on the limbal epithelial cell outgrowth was analyzed with a stepwise linear regression algorithm. The rate of successful human LEC outgrowth was 37.5%. From the stepwise linear regression algorithm, we found out that the relevant influencing parameters on the LEC growth were intercept (p < 0.001), donor age (p = 0.002), number of culture medium changes during organ culture (p < 0.001), total medium time (p = 0.181), and size of the used corneoscleral ring (p = 0.007), as well as medium time × size of the corneoscleral ring (p = 0.007). The success of LEC outgrowth increases with lower donor age, lower number of organ culture medium changes during storage, shorter medium time in organ culture, and smaller corneoscleral ring size. Our stepwise linear regression algorithm may help us in optimizing LEC cultures in vitro.

Extracellular vesicles from induced pluripotent stem cell-derived mesenchymal stem cells enhance the recovery of acute kidney injury

Background aimsTo investigate whether the extracellular vesicles (EVs) from mesenchymal stem cell–like cells derived from induced pluripotent stem cells (iMSC-EVs) can inhibit the progression of acute kidney injury (AKI). MethodsThe characteristics of iMSC-EVs were confirmed by immunoblotting, cryo-transmission electron microscopy, nanoparticle tracking analysis, and their localization in kidneys. Using human renal epithelial cells, the potential of iMSC-EVs to stimulate the growth and survival of HK-2 cells undergoing cisplatin-induced cell death was investigated. The anti-inflammatory effects of iMSC-EVs was examined in M1-polarized THP-1 macrophages. Subsequently, the therapeutic potential of iMSC-EVs was assessed in cisplatin-induced acute kidney injury in BALB/c mice. The anti-apoptotic and anti-inflammatory effect of iMSC-EVs was evaluated using serum biochemistry, histology, immunohistochemistry, and gene expression analysis. ResultsiMSC-EVs promoted the growth of renal epithelial cell (HK-2) and enhanced the survival of HK-2 undergoing cisplatin-induced cell death. In cisplatin-induced mice with AKI, iMSC-EVs alleviated AKI, as shown by reduced blood nitrogen urea/creatinine and increased body weight. Also, iMSC-EVs enhanced renal tissue integrity and the number of proliferating cell nuclear antigen–positive tubules. iMSC-EVs decreased the infiltration of immune cells, reduced the expression of inflammatory genes in M1-induced THP-1 cells and enhanced capillary density in the kidney of AKI mice. Real-time quantitative polymerase chain reaction analysis showed that the expression of inflammatory genes in the kidney of AKI mice was reduced compared with that received vehicle. Immunoblotting revealed that iMSC-EVs led to a decreased protein expression of key inflammatory genes. Also, iMSC-EVs reversed the activation of ERK1/2 signaling induced by AKI. Finally, iMSC-EVs inhibited the apoptosis of HK-2 cells induced by cisplatin as well as that of renal tissue of AKI mice. ConclusionsOur data suggest that iMSC-EVs have potential to become a novel, cell-free therapeutic for cisplatin-induced AKI.

Myeloid- and epithelial-derived RELMα contribute to tissue repair following lung helminth infection.

Soil-transmitted helminth (STH) infections impact billions of individuals globally; however, there is a need to clarify the long-term impacts of these infections on pulmonary health owing to their transient migration and subsequent damage to the lungs. In mouse models of these infections using Nippostrongylus brasiliensis, lung pathology persists at later time points post single infection. These studies also indicate the persistent transcriptional expression of resistin-like molecule α (RELMα), an immunomodulatory protein induced in type 2 immunity and alternatively activated macrophages. Using constitutive and tamoxifen-inducible cell-specific RELMα knockout mouse strains, we identified that epithelial- and myeloid-derived RELMα protein remained elevated at 30 days post infection and altered the immune cell signature and gene expression in lung compartments. Histopathological assessment of alveolar damage revealed a role for RELMα in tissue repair, suggesting the importance of sustained RELMα expression for lung recovery from helminth infection. Acellular three-dimensional (3D) lung scaffolds were prepared from the lungs of wild-type (WT), RELMα KO-naive, or 30 days post N. brasiliensis-infected mice to assess their ability to support epithelial cell growth. N. brasiliensis infection significantly altered the scaffold and impaired epithelial cell growth and metabolic activity, especially in the RELMα KO scaffolds. These findings underscore a need to identify the long-term impacts of helminth infection on human pulmonary disease, particularly as alveolar destruction can develop into chronic obstructive pulmonary disease (COPD), which remains among the top global causes of death. Translation of these findings to human protein resistin, with sequence homology to RELMα therapeutic opportunities in lung repair.

Hysteresis and Hopf bifurcation: Deciphering the dynamics of an in-host model of SARS-CoV-2 with logistic target cell growth and sigmoidal immune response

Mathematical models of in-host dynamics of SARS-CoV-2 may reveal the intricate underlying dynamics of host-pathogen interaction and guide crucial steps to curtail progression of COVID-19 and other similar infectious diseases. While the existing models on SARS-CoV-2 have considered a wide range of host-pathogen interactions, at their core, these models are remarkably similar, particularly in the choice of mathematical functions used in modeling the interactions. Specifically, these models have employed mass action kinetics while modeling target-cell interaction with virus particles and immune response to virus, thus overlooking the role of saturated evolution of target epithelial cells as well as immune cells. Here we fill this gap by developing a more comprehensive model of in-host dynamics of SARS-CoV-2 that concurrently models target epithelial cell growth using a logistic equation and virus-immune interaction using Michaelis–Menten kinetics. We identify a feasible disease-free equilibrium whose local stability depends on ”reproduction number” and global stability on the replenishment rate as well as the removal rate of immune cells. We also obtain multiple endemic equilibria and perform their local and global stability analysis. Our detailed numerical investigation demonstrates that the infection rate and reproduction number govern several interesting dynamical behaviors such as forward bifurcation with and without hysteresis, Hopf bifurcation, and multiple endemic equilibria. To analyze the impact of parameters on the model system and disease dynamics, we investigate several sensitive parameters and compute their sensitivity indices. Finally, to understand the impact of anti-viral therapy on viral load, we identify a novel threshold of replication rate that must be crossed to enable virus proliferation. Our results thus provide novel insights into the in-host dynamics of SARS-CoV-2 and we expect this model will help in the development of better treatment strategies for COVID-19 and other such infectious diseases.

HGF/C-Met Expression in Epithelial Ovarian Carcinogenesis and Its Potential as Molecular Targeted Therapy

Background: The Mesenchymal-Epithelial Transition factor (C-Met) is a tyrosine kinase receptor (TKR) that binds to a ligand called Hepatocyte Growth Factor (HGF). Recent studies conducted on patients with epithelial ovarian cancer (EOC) reported that high expression of C-Met was associated with poorer clinicopathological grading and outcomes. Therefore, this study aimed to further explore the downstream pathway specifically activated when the HGF/C-Met complex was formed, the interplay between C-Met and other molecules, as well as the impact on EOC when these interactions were inhibited through designated molecular targeted therapy.Methods: The search strategy using the PubMed search engine (https://pubmed.ncbi.nlm.nih.gov/) was conducted on September 21, 2022, with the keywords: “HGF/C-Met and ovarian cancer”. The search resulted in 261 articles, and they were filtered by “published in the last five years,” which yielded 67 articles. These articles then underwent further screening, resulting in 40 articles for analysis. A systematic literature review was conducted to improve the quality of this study. Approximately 150 articles were thoroughly examined and organized using a reference manager, then 15 with the greatest impact and clinical relevance to this study were selected. Results: The HGF/C-Met complex was found to stimulate signaling pathways linked to the growth of epithelial cells and also caused the phosphorylation of tyrosine residues on other tyrosine receptors. The activation of C-Met affected the downstream pathways involving molecules associated with cell proliferation and survival, such as epidermal growth factor receptor (EGFR), p53, and KRAS. C-Met can be combined with other tyrosine kinase inhibitors in chemotherapy to enhance the initiation of cell death (apoptosis) in cancer cells.Conclusions: The HGF/C-Met mediated a signaling cascade that played an essential role in the tumorigenesis of ovarian carcinoma and had the potential to be a targeted molecular therapy in EOC

Benign prostatic hyperplasia and the urinary tract repercussions

Known as the most common urological disease, benign prostatic hyperplasia (BPH) is a condition that affects men from 40 years of age. Linked to metabolic, hormonal and inflammatory mechanisms, the disease causes growth of prostatic tissue, epithelial and stromal cells, compressing the urethra, resulting in resistance to the output of urine from the bladder and the main complaints of the disease, the symptoms of the lower urinary tract (LUTS). This study aims to inform about benign prostatic hyperplasia and its main symptoms of the lower urinary tract, since these LUTS negatively affect affected patients. This is a literature review with articles published on the subject in the last 7 years, through an electronic search in the main bibliographic indexes. The benign growth of the prostate gland and its obstructive and irritating urinary symptoms such as: urgency to urinate, hesitation, forced urination with slow flow, nocturia and irritation, negatively affect the quality of life of most patients. Diagnosed in a simple way, based on the patient's clinical history, physical examination and digital rectal examination, in addition to laboratory and imaging tests, such as transrectal ultrasound, BPH has an excellent prognosis. For the treatment, the degree of the patient's symptoms is evaluated through a questionnaire, the International Prostate Symptom Score (IPSS), the classification in mild, moderate and severe defines the conduct. Watchful waiting, a treatment for patients with mild symptoms, is the most common. The existing drug classes aim to reduce LUTS and slow down the progression of the disease. The growth of the prostate gland and the consequent compression of the urethra, causes several complaints and losses in the daily life of men who have BPH, therefore, knowing the signs and symptoms of the disease is essential for it to be effectively diagnosed and treated.

Biofilm's Impact on Inflammatory Bowel Diseases.

The colon has a large surface area covered with a thick mucus coating. Colon's biomass consists of about 1,012 colony-forming units per gram of feces and 500-1,000 distinct bacterial species.The term inflammatory bowel disease(IBD) indicates the collection of intestinal illnesses in which the digestive system (esophagus, large intestine, mouth, stomach, and small intestine) experiences persistent inflammation. IBD development is influenced by environmental (infections, stress, and nutrition) and genetic factors. The microbes present in gut microbiotahelp maintain intestinal homeostasisand support immune and epithelial cell growth, differentiation, as well as proliferation. It has been discovered that a variety of variables and microorganisms are crucial for the development of biofilms and mucosal colonization during IBD. An extracellular matrix formed by bacteria supports biofilm production in our digestive system and harms the host's immunological response. Irritable bowel syndrome (IBS) and IBDconsiderably affect human socioeconomic well-being and the standard of living. IBD is a serious public health issue, affecting millions of people across the globe. The gut microbiome may significantly influence IBS pathogenesis, even though few diagnostic and treatment options are available. As a result, current research focuses more on disrupting biofilm in IBD patients and stresses primarily on drugs that help improve the quality of life for human well-being. We evaluate studies on IBD and bacterial biofilm to add fresh insights into the existing state of knowledge of biofilm formation in IBD, incidence of IBD patients, molecular level of investigations, bacteria that are involved in the formation of biofilm, and present and down the line regimens and probiotics. Planning advanced ways to control and eradicate bacteria in biofilms should be the primary goal to add fresh insights into generating innovative diagnostic and alternative therapy options for IBD.

Glutamine Regulates Gene Expression Profiles to Increase the Proliferation of Porcine Intestinal Epithelial Cells and the Expansion of Intestinal Stem Cells.

The intestinal epithelium is known for its rapid self-renewal, and glutamine is crucial in providing carbon and nitrogen for biosynthesis. However, understanding how glutamine affects gene expression in the intestinal epithelium is limited, and identifying the essential genes and signals involved in regulating intestinal epithelial cell growth is particularly challenging. In this study, glutamine supplementation exhibited a robust acceleration of intestinal epithelial cell proliferation and stem cell expansion. RNA sequencing indicated diverse transcriptome changes between the control and glutamine supplementation groups, identifying 925 up-regulated and 1152 down-regulated genes. The up-regulated DEGs were enriched in the KEGG pathway of cell cycle and GO terms of DNA replication initiation, regulation of phosphatidylinositol 3-kinase activity, DNA replication, minichromosome maintenance protein (MCM) complex, and ATP binding, whereas the down-regulated DEGs were enriched in the KEGG pathway of p53 signaling pathway, TNF signaling pathway, and JAK-STAT signaling pathway and GO terms of inflammatory response and intrinsic apoptotic signaling pathway in response to endoplasmic reticulum stress. Furthermore, GSEA analysis revealed a significant up-regulation of the cell cycle, DNA replication initiation, ATP-dependent RNA helicase activity, and down-regulation of the TNF signaling pathway. The protein-protein association network of the intersecting genes highlighted the significance of DNA replication licensing factors (MCM3, MCM6, and MCM10) in promoting intestinal epithelial growth in response to glutamine. Based on these findings, we propose that glutamine may upregulate DNA replication licensing factors, leading to increased PI3K/Akt signaling and the suppression of TNF, JAK-STAT, and p53 pathways. Consequently, this mechanism results in the proliferation of porcine intestinal epithelial cells and the expansion of intestinal stem cells.

Integration and deconvolution methodology deciphering prognosis-related signatures in lung adenocarcinoma.

This study aims to establish a risk prediction model based on prognosis-related genes (PRGs) and clinicopathological factors, and investigate the biological activities of PRGs in lung adenocarcinoma (LUAD). Risk score signatures were developed by employing multiple algorithms and their amalgamations. A predictive model for overall survival was established through the integration of risk score signatures and several clinicopathological parameters. A comprehensive single-cell atlas, gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA) were used to investigate the biological activities of prognosis-related genes in LUAD. A risk prediction model was established based on 16 PRGs, exhibiting robust performance in predicting overall survival. The single-cell analysis revealed that epithelial cells were primarily associated with worse survival of LUAD, and PRGs were predominantly enriched in malignant epithelial cells and influenced epithelial cell growth and progression. Furthermore, GSEA and GSVA analysis showed that PRGs were involved in tumor pathways such as epithelial-mesenchymal transition, hypoxia and KRAS_UP, and high GSVA scores are correlated with worse outcome in LUAD patients. The constructed risk prediction model in this study offers clinicians a valuable tool for tailoring treatment strategies of LUAD and provides a comprehensive interpretation on the biological activities of PRGs in LUAD.

Identification of Small Inhibitors for Human Metadherin, an Oncoprotein, through in silico Approach.

Cancer is a disease that takes lives of thousands of people each year. There are more than 100 different types of cancers known to man. This fatal disease is one of the leading causes of death today. Astrocyte elevated gene-1(AEG-1)/Metadherin (MTDH) activates multiple oncogenic signaling pathways and leads to different types of cancers. MTDH interacting with staphylococcal nuclease domain containing 1(SND1) supports the survival and growth of mammary epithelial cells under oncogenic conditions. Silencing MTDH or SND1 individually or disrupting their interaction compromises the tumorigenic potential of tumor-initiating cells. The aim of our present study was to investigate novel interactions of staphylococcal nuclease domain containing 1 (SND1) binding domain of AEG-1/MTDH with different lead compounds through molecular docking approach using MOE software. Molecular docking was done by docking the ChemBridge database against important residues of MTDH involved in interaction with SND1. After docking the whole ChemBridge database, the top 200 interactive compounds were selected based on docking scores. After applying Lipinski's rule, all the remaining chosen compounds were studied on the basis of binding affinity, binding energy, docking score and protein-ligand interactions. Finally, 10 compounds showing multiple interactions with different amino acid residues were selected as the top interacting compounds. Three compounds were selected for simulation studies after testing these compounds using topkat toxicity and ADMET studies. The simulation study indicated that compound 32538601 is a lead compound for inhibiting MTDH-SND1 complex formation. These novels, potent inhibitors of MTDH-SND1 complex can ultimately help us in controlling cancer up to some extent.

Efficacy of Loop Electrosurgical Excision Procedure in the Management of Cervical Intraepithelial Neoplasia (CIN) –in A Tertiary Level Hospital

Background: Cervical intraepithelial neoplasia (CIN) is the potentially premalignant transformation and abnormal growth of surface epithelial cells of the cervix. CIN is a precancerous condition and curable. Loop electrosurgical excision procedure (LEEP) is a simple, outpatient procedure of removing the transformation zone of cervix. The aim of our study was to evaluate the efficacy of large loop electrosurgical excision procedure (LEEP) as a treatment procedure for cervical intraepiethelial neoplasia. Methods: This prospective observational study was conducted at Colposcopy clinic of Bangabandhu Sheikh Mujib Medical University (BSMMU) from June, 2017 to May, 2019. All consecutive patients having colposcopicaly and histopathologicaly proven high grade lesion by colposcopy directed punch biopsy were included in this study. All eligible patients with high grade lesion were underwent LEEP and followed up on 15 days post-procedure, 6 months, 12 months with colposcopy. Results: Sixty (60) cases were undergone LEEP, among them 48 (80%) cases were diagnosed as CIN2 and 12 (20%) cases were CIN3 by colposcopy- directed biopsy. One patient (1.7%) needed hospital admission to controll intra-operative bleeding and in postoperative period 7 (11.7%) patients had mild to moderate post-operative bleeding which was controlled well after application of morsel’s pastes and electro-cautery, one patient (1.7%) had pelvic infection. On 6 months follow-up, in case of CIN2 patients, cure rate was 93.5% (43 of 46) and 1 (2.2%) patient had persistent CIN-2. Patient with persistent CIN2 had re-excision and followed up at 12 month with colposcopy. Among case of CIN-3, the cure rate was 81.8% (9 of 11) and 1 (9.1%) case had CIN2. P-value was 0.244, which was not statistically significant. Overall cure rate on 6 month follow-up was 91.2%. On 12 months follow-up cure rate for CIN2 was 97.8% and for CIN3 was 90.9%. Overall cure rate was 96.5%. P-value was 0.352, which was not statistically significant. Conclusion: Loop electrosurgical excision procedure (LEEP) has a good outcome as a diagnostic and treatment procedure for cervical intraepithelial neoplasia. Bangladesh Medical Res Counc Bull 2023; 49(2): 113-119

SUMOylation of AnxA6 facilitates EGFR-PKCα complex formation to suppress epithelial cancer growth

BackgroundThe Annexin A6 (AnxA6) protein is known to inhibit the epidermal growth factor receptor (EGFR)-extracellular signal regulated kinase (ERK)1/2 signaling upon EGF stimulation. While the biochemical mechanism of AnxA6 inactivating phosphorylation of EGFR and ERK1/2 is not completely explored in cancer cells.MethodsCells were transiently co-transfected with pFlag-AnxA6, pHA-UBC9 and pHis-SUMO1 plasmids to enrich the SUMOylated AnxA6 by immunoprecipitation, and the modification level of AnxA6 by SUMO1 was detected by Western blot against SUMO1 antibody. The SUMOylation level of AnxA6 was compared in response to chemical SUMOylation inhibitor treatment. AnxA6 SUMOylation sites were further identified by LC–MS/MS and amino acid site mutation validation. AnxA6 gene was silenced through AnxA6 targeting shRNA-containing pLKO.1 lentiviral transfection in HeLa cells, while AnxA6 gene was over-expressed within the Lenti-Vector carrying AnxA6 or mutant AnxA6K299R plasmid in A431 cells using lentiviral infections. Moreover, the mutant plasmid pGFP-EGFRT790M/L858R was constructed to test AnxA6 regulation on EGFR mutation-induced signal transduction. Moreover, cell proliferation, migration, and gefitinib chemotherapy sensitivity were evaluated in HeLa and A431 cells under AnxA6 konckdown or AnxA6 overexpression by CCK8, colony form and wound healing assays. And tumorigenicity in vivo was measured in epithelial cancer cells-xenografted nude mouse model.ResultsAnxA6 was obviously modified by SUMO1 conjugation within Lys (K) residues, and the K299 was one key SUMOylation site of AnxA6 in epithelial cancer cells. Compared to the wild type AnxA6, AnxA6 knockdown and its SUMO site mutant AnxA6K299R showed less suppression of dephosphorylation of EGFR-ERK1/2 under EGF stimulation. The SUMOylated AnxA6 was prone to bind EGFR in response to EGF inducement, which facilitated EGFR-PKCα complex formation to decrease the EGF-induced phosphorylation of EGFR-ERK1/2 and cyclin D1 expression. Similarly, AnxA6 SUMOylation inhibited dephosphorylation of the mutant EGFR, thereby impeding EGFR mutation-involved signal transduction. Moreover, AnxA6 knockdown or the K299 mutant AnxA6K299R conferred AnxA6 inability to suppress tumor progression, resulting in drug resistance to gefitinib in epithelial cancer cells. And in epithelial cancer cells-xenografted nude mouse model, both the weight and size of tumors derived from AnxA6 knockdown or AnxA6K299R mutation-expressing cells were much greater than that of AnxA6-expressing cells.ConclusionsBesides EGFR gene mutation, protein SUMOylation modification of EGFR-binding protein AnxA6 also functions pivotal roles in mediating epithelial cancer cell growth and gefitinib drug effect.4V8MbH9D2-V-dxkGbe_YjXVideo

CHAF1A promotes the proliferation and growth of epithelial ovarian cancer cells by affecting the phosphorylation of JAK2/STAT3 signaling pathway

The molecular mechanism of chromatin assembly factor 1 unit A (CHAF1A) promoting the proliferation and growth of epithelial ovarian cancer (EOC) cells hasn’t been reported at present. In this study, recombinant CHAF1A siRNA/overexpression plasmid (si-RNA1/pcDNA3.1-CHAF1A) was designed and constructed, and stable cell lines with knockdown or overexpression of CHAF1A were constructed. The changes of JAK2/STAT3 pathway were detected by Western blot. JAK2/STAT3 pathway was inhibited by Peficitinib, and then cell proliferation and growth ability were detected. Bioinformatics analysis suggested that CHAF1A was up-regulated in epithelial ovarian cancer. JAK2/STAT3 pathway phosphorylation was inhibited in si-RNA1 group, while it was increased in pcDNA3.1-CHAF1A group. After inhibiting JAK2/STAT3 pathway, the promoting effect of CHAF1A on epithelial ovarian cancer cell proliferation disappeared, meanwhile the inhibitory effect of CHAF1A on apoptosis enhanced. In conclusion, CHAF1A promotes the proliferation and growth of epithelial ovarian cancer cells by affecting the phosphorylation of JAK2/STAT3 signaling pathway.

Host–device interactions: exposure of lung epithelial cells and fibroblasts to nickel, titanium, or nitinol affect proliferation, reactive oxygen species production, and cellular signaling

Endoscopic implantation of medical devices for the treatment of lung diseases, including airway stents, unidirectional valves and coils, is readily used to treat central airway disease and emphysema. However, granulation and fibrotic tissue formation impairs treatment effectiveness. To date little is known about the interaction between implanted devices, often made from metals, such as nickel, titanium or nitinol, and cells in the airways. Here, we study the response of lung epithelial cells and fibroblasts to implant device materials. The adhesion and proliferation of bronchial epithelial cells and lung fibroblasts upon exposure to 10 × 3 × 1 mm pieces of nickel, titanium or nitinol is examined using light and scanning electron microscopy. Pro-inflammatory cytokine mRNA expression and release, signaling kinase activity and intracellular free radical production are assessed. Nitinol, and to a lesser extent nickel and titanium, surfaces support the attachment and growth of lung epithelial cells. Nitinol induces a rapid and significant alteration of kinase activity. Cells directly exposed to nickel or titanium produce free radicals, but those exposed to nitinol do not. The response of lung epithelial cells and fibroblasts depends on the metal type to which they are exposed. Nitinol induces cellular surface growth and the induction of kinase activity, while exposure of lung epithelial cells to nickel and titanium induces free radical production, but nitinol does not.Graphical

Glucose promotes cell growth and casein synthesis via ATF4/Nrf2-Sestrin2- AMPK-mTORC1 pathway in dairy cow mammary epithelial cells

In the dairy industry, glucose (Glu) is used as bioactive substance to increase milk yield. However, the molecular regulation underneath needs further clarification. Here, the regulation and its molecular mechanism of Glu on cell growth and casein synthesis of dairy cow mammary epithelial cells (DCMECs) were investigated. When Glu was added from DCMECs, both cell growth, β-casein expression and the mechanistic target of rapamycin complex 1 (mTORC1) pathway were increased. Overexpression and silencing of mTOR revealed that Glu promoted cell growth and β-casein expression through the mTORC1 pathway. When Glu was added from DCMECs, both Adenosine 5'-monophosphate-activated protein kinase α (AMPKα) and Sestrin2 (SESN2) expression were decreased. Overexpression and silencing of AMPKα or SESN2 uncovered that AMPKα suppressed cell growth and β-casein synthesis through inhibiting mTORC1 pathway, and SESN2 suppressed cell growth and β-casein synthesis through activating AMPK pathway. When Glu was depleted from DCMECs, both activating transcription factor 4 (ATF4) and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) expression were increased. Overexpression or silencing of ATF4 or Nrf2 demonstrated that Glu depletion promoted SESN2 expression through ATF4 and Nrf2. Together, these results indicate that in DCMECs, Glu promoted cell growth and casein synthesis via ATF4/Nrf2-SESN2-AMPK-mTORC1 pathway.

Preparation and Characterization of a Photo-Crosslinked Methacryloyl-Collagen Composite Film to Promote Corneal Nerve Regeneration via Surface Grafting of Taurine Molecules.

Blindness is frequently caused by corneal abnormalities, and corneal transplantation is the most effective treatment method. It is extremely important to develop high-quality artificial corneas because there are not enough donor corneas accessible for cornea transplantation. One of the most-often utilized materials is collagen, which is the primary component of natural cornea. Collagen-based corneal repair materials have good physicochemical properties and excellent biocompatibility, but how to promote the regeneration of the corneal nerve after keratoplasty is still a big challenge. In this research, in order to promote the growth of nerve cells on a collagen (Col) substrate, a novel collagen-based material was synthesized starting from the functionalization of collagen with unsaturated methacryloyl groups that three-dimensionally photopolymerize to a 3D network of chemically crosslinked collagen (ColMA), onto which taurine molecules were eventually grafted (ColMA-Tr). The physicochemical properties and biocompatibility of the Col, ColMA and ColMA-Tr films were evaluated. By analyzing the results, we found that all the three samples had good moisture retention and aq high covalent attachment of methacryloyl groups followed by their photopolymerization improved the mechanical properties of the ColMA and ColMA-Tr. Most importantly, compared with ColMA, the taurine-modified collagen-MA film significantly promoted the growth of nerve cells and corneal epithelial cells on its surface. Our preliminary results suggest that this novel ColMA-Tr film may have potential use in cornea tissue engineering in the future.