Regulation Of Receptors Research Articles

The Role of Impaired Receptor Trafficking in Mediating the Pathological Effects of APOE4 in Alzheimer's Disease.

Apolipoprotein E4 (APOE4) is the most prevalent genetic risk factor of Alzheimer's disease. Several studies suggest that APOE4 binding to its receptors is associated with their internalization and accumulation in intracellular compartments. Importantly, this phenomenon also occurs with other, non-ApoE receptors. Based on these observations, we hypothesized that APOE4 pathological effects are mediated by impairment in the life cycle of distinct receptors (APOER2, LRP1, IR, VEGFR). To examine the effects of APOE genotype on receptors protein levels and compartmentalization. Primary mouse neurons were prepared from APOE3 or APOE4 targeted replacement mice, or APOE-KO mice. Specific receptors protein levels were evaluated in these neurons, utilizing immunofluorescent staining. Additionally, surface membrane protein levels of those receptors were assessed by cell surface biotinylation assay and ELISA. Receptors' colocalization with intracellular compartments was assessed by double staining and confocal microscopy, followed by colocalization analysis. Finally, LRP1 or APOER2 were knocked-down with CRISPR/Cas9 system to examine their role in mediating APOE4 effects on the receptors. Our results revealed lower receptors' levels in APOE4, specifically on the membrane surface. Additionally, APOE4 affects the compartmentation of these receptors in two patterns: the first was observed with LRP1 and was associated with decreased receptor levels in numerous intracellular compartments. The second was obtained with the other receptors and was associated with their accumulation in early endosomes and their decrease in the late endosomes. These results provide a unifying mechanism, in which APOE4 drives the down regulation of various receptors, which plays important roles in distinct APOE4 related pathological processes.

Abstract C103: Differential acquisition of extracellular lipid correlates with pancreatic cancer subtype and metastatic tropism

Abstract Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease, and the third leading cause of cancer-related death with a 5-year overall survival rate of less than 5%. Recent studies have identified two major subtypes of pancreatic cancer, basal and classical, that are predictive of patient prognosis, with basal tumors corresponding with more aggressive disease. While transcriptional signatures define basal and classical tumors and cell lines, little is known regarding the metabolic vulnerabilities linked to the basal versus classical state. Using unbiased computational interrogation to uncover metabolic genes correlating with known markers of classical PDAC, we identified high expression of Proprotein convertase subtilisin/kexin type-9 (PCSK9) – a negative regulator of receptor mediated uptake of cholesterol containing low-density lipoprotein (LDL) – as correlating with several established markers of classical PDAC. In contrast, PCSK9 expression is suppressed in Basal PDAC. Accordingly, basal PDAC uptake high levels of LDL, are sensitive to LDL depletion and show higher dependence on cholesterol uptake, relative to classical PDAC. As lipoproteins are produced in the liver, we hypothesized that basal PDAC cells may more efficiently seed and grow within the liver. Consistent with this hypothesis, low PCSK9 expression is correlated with liver metastasis in mouse models of PDAC and patient PDAC specimens. Ongoing studies will interrogate the role of PCSK9 and cholesterol uptake and utilization in metastatic tropism, and uncover unique features and vulnerabilities of the most aggressive variant of PDAC. Citation Format: Gilles Rademaker, Grace A. Hernandez, Longhui Qiu, Kwun W. Wen, Aakriti Jain, Grace A. Kim, Roberto Zoncu, Rushik M. Perera. Differential acquisition of extracellular lipid correlates with pancreatic cancer subtype and metastatic tropism [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr C103.

Novel mechanism of androgen receptor regulation through switching by long non‐coding RNA LINC01126

Novel mechanism of androgen receptor regulation through switching by long non‐coding RNA LINC01126

Exploring the potential mechanism and molecular targets of Taohong Siwu Decoction against deep vein thrombosis based on network pharmacology and analysis docking.

This study aims to investigate the mechanism of Taohong Siwu Decoction (THSWD) against deep vein thrombosis (DVT) using network pharmacology and molecular docking technology. We used the Traditional Chinese Medicine Systems Pharmacology database and reviewed literature to identify the main chemical components of THSWD. To find targets for DVT, we consulted GeneCards, Therapeutic Target Database, and PharmGKB databases. We used Cytoscape 3.8.2 software to construct herb-disease-gene-target networks. Additionally, we integrated drug targets and disease targets on the STRING platform to create a protein-protein interaction network. Then, we conducted Kyoto Encyclopedia of Genes and Genomes and gene ontology analysis. Finally, We employed the molecular docking method to validate our findings. We identified 56 potential targets associated with DVT and found 61 effective components. beta-sitosterol, quercetin, and kaempferol were the most prominent among these components. Our analysis of the protein-protein interaction network revealed that IL6, L1B, and AKT1 had the highest degree of association. Gene ontology analysis showed that THSWD treatment for DVT may involve response to inorganic substances, negative regulation of cell differentiation, plasma membrane protein complex, positive regulation of phosphorylation, and signaling receptor regulator activity. Kyoto Encyclopedia of Genes and Genomes analysis indicated that lipid and atherosclerosis, pathways in cancer, as well as the PI3K-Akt pathway are the main signal pathways involved. Molecular docking results demonstrated strong binding affinity between beta-sitosterol, quercetin, kaempferol, and AKT1 proteins as well as IL1B and IL6 proteins. The main targets for THSWD treatment of DVT may include AKT1, IL1B, and IL6. Beta-sitosterol, quercetin, and kaempferol may be the active ingredients responsible for producing this effect. These compounds may slow down the progression of DVT by regulating the inflammatory response through the PI3K/Akt pathway.

Structural basis for the activity and specificity of the immune checkpoint inhibitor lirilumab

The clinical success of immune checkpoint inhibitors has underscored the key role of the immune system in controlling cancer. Current FDA-approved immune checkpoint inhibitors target the regulatory receptor pathways of cytotoxic T-cells to enhance their anticancer responses. Despite an abundance of evidence that natural killer (NK) cells can also mediate potent anticancer activities, there are no FDA-approved inhibitors targeting NK cell specific checkpoint pathways. Lirilumab, the most clinically advanced NK cell checkpoint inhibitor, targets inhibitory killer immunoglobulin-like receptors (KIRs), however it has yet to conclusively demonstrate clinical efficacy. Here we describe the crystal structure of lirilumab in complex with the inhibitory KIR2DL3, revealing the precise epitope of lirilumab and the molecular mechanisms underlying KIR checkpoint blockade. Notably, the epitope includes several key amino acids that vary across the human population, and binding studies demonstrate the importance of these amino acids for lirilumab binding. These studies reveal how KIR variations in patients could influence the clinical efficacy of lirilumab and reveal general concepts for the development of immune checkpoint inhibitors targeting NK cells.

IKAROS and AIOLOS directly regulate AP-1 transcriptional complexes and are essential for NK cell development.

Ikaros transcription factors are essential for adaptive lymphocyte function, yet their role in innate lymphopoiesis is unknown. Using conditional genetic inactivation, we show that Ikzf1/Ikaros is essential for normal natural killer (NK) cell lymphopoiesis and IKZF1 directly represses Cish, a negative regulator of interleukin-15 receptor resulting in impaired interleukin-15 receptor signaling. Both Bcl2l11 and BIM levels, and intrinsic apoptosis were increased in Ikzf1-null NK cells, which in part accounts for NK lymphopenia as both were restored to normal levels when Ikzf1 and Bcl2l11 were co-deleted. Ikzf1-null NK cells presented extensive transcriptional alterations with reduced AP-1 transcriptional complex expression and increased expression of Ikzf2/Helios and Ikzf3/Aiolos. IKZF1 and IKZF3 directly bound AP-1 family members and deletion of both Ikzf1 and Ikzf3 in NK cells resulted in further reductions in Jun/Fos expression and complete loss of peripheral NK cells. Collectively, we show that Ikaros family members are important regulators of apoptosis, cytokine responsiveness and AP-1 transcriptional activity.

Eat at the right time: Regulation of ER-phagy receptors in plant response to environmental stresses

The endoplasmic reticulum (ER) is the site where proteins and lipids are made. Recent research has spotlighted ER-phagy, a selective autophagy of the ER, as an important player in plant adaptation to environmental stresses. Central to ER-phagy are diverse ER-phagy receptors in both mammalian and plant cells that not only facilitate the selective degradation of the ER but also participate in the formation of the ER under normal conditions. How do cells modulate these two actions of ER-phagy receptors? Recent studies suggest that three post-translational modifications: ubiquitination, phosphorylation and UFMylation, may act as switches for these dual roles. Given the importance of ER-phagy in plant stress responses, understanding the factors that govern these dual functions is crucial. Here we seek to integrate recent research in ER-phagy receptors in mammalian and plant cells. We hypothesize that ubiquitination and phosphorylation operate collaboratively in plant cells to determine action of ER-phagy receptors in tubular ER-phagy, while UFMylation acts in rough/sheet ER-phagy. We also suggest the need for further investigations into the specificity of ER-phagy receptors and signal pathways that relay environmental stresses to the two post-translational modifications of ER-phagy receptors.

Molecular mechanism of antihistamines recognition and regulation of the histamine H1 receptor

Histamine receptors are a group of G protein-coupled receptors (GPCRs) that play important roles in various physiological and pathophysiological conditions. Antihistamines that target the histamine H1 receptor (H1R) have been widely used to relieve the symptoms of allergy and inflammation. Here, to uncover the details of the regulation of H1R by the known second-generation antihistamines, thereby providing clues for the rational design of newer antihistamines, we determine the cryo-EM structure of H1R in the apo form and bound to different antihistamines. In addition to the deep hydrophobic cavity, we identify a secondary ligand-binding site in H1R, which potentially may support the introduction of new derivative groups to generate newer antihistamines. Furthermore, these structures show that antihistamines exert inverse regulation by utilizing a shared phenyl group that inserts into the deep cavity and block the movement of the toggle switch residue W4286.48. Together, these results enrich our understanding of GPCR modulation and facilitate the structure-based design of novel antihistamines.

Cortisol controls endoplasmic reticulum stress and hypoxia dependent regulation of insulin receptor and related genes expression in HEK293 cells.

Objective. Glucocorticoids are important stress-responsive regulators of insulin-dependent metabolic processes realized through specific changes in genome function. The aim of this study was to investigate the impact of cortisol on insulin receptor and related genes expression in HEK293 cells upon induction the endoplasmic reticulum (ER) stress by tunicamycin and hypoxia. Methods. The human embryonic kidney cell line HEK293 was used. Cells were exposed to cortisol (10 µM) as well as inducers of hypoxia (dimethyloxalylglycine, DMOG; 0.5 mM) and ER stress (tunicamycin; 0.2 µg/ml) for 4 h. The RNA from these cells was extracted and reverse transcribed. The expression level of INSR, IRS2, and INSIG2 and some ER stress responsive genes encoding XBP1n, non-spliced variant, XBP1s, alternatively spliced variant of XBP1, and DNAJB9 proteins, was measured by quantitative polymerase chain reaction and normalized to ACTB. Results. We showed that exposure of HEK293 cells to cortisol elicited up-regulation in the expression of INSR and DNAJB9 genes and down-regulation of XBP1s, XBP1n, IRS2, and INSIG2 mRNA levels. At the same time, induction of hypoxia by DMOG led to an up-regulation of the expression level of most studied mRNAs: XBP1s and XBP1n, IRS2 and INSIG2, but did not change significantly INSR and DNAJB9 gene expression. We also showed that combined impact of cortisol and hypoxia introduced the up-regulation of INSR and suppressed XBP1n mRNA expression levels. Furthermore, the exposure of HEK293 cells to tunicamycin affected the expression of IRS2 gene and increased the level of XBP1n mRNA. At the same time, the combined treatment of these cells with cortisol and inductor of ER stress had much stronger impact on the expression of all the tested genes: strongly increased the mRNA level of ER stress dependent factors XBP1s and DNAJB9 as well as INSR and INSIG2, but down-regulated IRS2 and XBP1n. Conclusion. Taken together, the present study indicates that cortisol may interact with ER stress and hypoxia in the regulation of ER stress dependent XBP1 and DNAJB9 mRNA expression as well as INSR and its signaling and that this corticosteroid hormone modified the impact of hypoxia and especially tunicamycin on the expression of most studied genes in HEK293 cells. These data demonstrate molecular mechanisms of glucocorticoids interaction with ER stress and insulin signaling at the cellular level.

The analgesic effect of paeoniflorin: A focused review.

Pain has been a prominent medical concern since ancient times. Despite significant advances in the diagnosis and treatment of pain in contemporary medicine, there is no a therapeutic cure for chronic pain. Chinese herbaceous peony, a traditional Chinese analgesic herb has been in clinical use for millennia, with widespread application and substantial efficacy. Paeoniflorin (PF), the main active ingredient of Chinese herbaceous peony, has antioxidant, anti-inflammatory, anticancer, analgesic, and antispasmodic properties, among others. The analgesic effect of PF, involving multiple critical targets and pain regulatory pathways, has been a hot spot for current research. This article reviews the literature related to the analgesic effect of PF in the past decade and discusses the molecular mechanism of the analgesic effect of PF, including the protective effects of nerve cells, inhibition of inflammatory reactions, antioxidant effects, reduction of excitability in nociceptor, inhibition of the nociceptive excitatory neuroreceptor system, activation of the nociceptive inhibitory neuroreceptor system and regulation of other receptors involved in nociceptive sensitization. Thus, providing a theoretical basis for pain prevention and treatment research. Furthermore, the prospect of PF-based drug development is presented to propose new ideas for clinical analgesic therapy.

Exploration of the molecular mechanism guiding Xinfeng capsule regulatory mechanism for rheumatoid arthritis inflammation.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joint synovium. The traditional Chinese medicine Xinfeng capsule (XFC) has a remarkable alleviating effect on inflammatory symptoms, such as joint pain and swelling, in patients with RA. However, the underlying mechanism of action remains to be elucidated. This study intended to conduct network pharmacology, animal experiments, data mining, and molecular docking to explore the molecular mechanism through which XFC can improve the inflammatory symptoms of RA. The Apriori association rules and a random walk model were employed to evaluate the effect of XFC on the clinical inflammatory indexes of RA. The active ingredients and the potential target genes of XFC were obtained from public databases. Based on the search tool for recurring instances of neighboring genes (STRING) database, the Database for Annotation, Visualization and Integrated Discovery (DAVID) database, Cytoscape software, and molecular docking method, the molecular mechanism by which XFC acts on RA was also analyzed. Finally, an adjuvant arthritis rat model was established to verify the effects of XFC on inflammation-related signaling pathways and inflammatory factors. XFC significantly reduced the level of C-reactive protein (CRP), vascular endothelial growth factor (VEGF), and the erythrocyte sedimentation rate (ESR). The docking space structures of the active ingredients in XFC, namely triptolide and quercetin, and the key targets were stable. Inflammation-related biological processes were identified as the key factors involved in the development of RA, and the regulation of the toll-like receptor (TLR) signaling pathway may be the key link for XFC toward improving the inflammatory state of RA. The expression levels of toll-like receptor 4 (TLR4), myeloid differentiation primary response protein MyD88 (MyD88), interleukin-1 receptor-associated kinase 1 (IRAK1), TNF receptor-associated factor 6 (TRAF6), TGF-beta-activated kinase 1 (TAK1), phospho-Inhibitor of NF-κB kinaseβ (p-IKKβ), phospho-Nuclear factor-k-gene binding (p-NF-κB), and interleukin-1β (IL-1β) can all be decreased by XFC. XFC improves joint inflammation symptoms by lowering pro-inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interferon-γ (INF-γ) levels. XFC could effectively improve the clinical inflammatory indexes of RA. The active ingredients of XFC improved the inflammatory state of RA by regulating the TLR-signaling pathway.

Probiotics induce intestinal IgA secretion in weanling mice potentially through promoting intestinal APRIL expression and modulating the gut microbiota composition.

Intestinal infections are strongly associated with infant mortality, and intestinal immunoglobulin A (IgA) is important to protect infants from intestinal infections after weaning. This study aims to screen probiotics that can promote the production of intestinal IgA after weaning and further explore their potential mechanisms of action. In this study, probiotics promoting intestinal IgA production were screened in weanling mouse models. The results showed that oral administration of Bifidobacterium bifidum (B. bifidum) FL228.1 and Bifidobacterium bifidum (B. bifidum) FL276.1 significantly enhanced IgA levels in the small intestine and upregulated the expression of a proliferation-inducing ligand (APRIL) and its upstream regulatory factor toll-like receptor 4 (TLR4). Furthermore, B. bifidum FL228.1 upregulated the relative abundance of Lactobacillus, while B. bifidum FL276.1 increased the relative abundance of Marvinbryantia and decreased Mucispirillum, further elevating intestinal IgA levels. In summary, B. bifidum FL228.1 and B. bifidum FL276.1 can induce IgA production in the intestinal tract of weanling mice by promoting intestinal APRIL expression and mediating changes in the gut microbiota, thus playing a significant role in enhancing local intestinal immunity in infants.

The role of CD4+ T cells in visceral leishmaniasis; new and emerging roles for NKG7 and TGFβ.

Visceral leishmaniasis is a potentially devastating neglected tropical disease caused by the protozoan parasites Leishmania donovani and L. infantum (chagasi). These parasites reside in tissue macrophages and survive by deploying a number of mechanisms aimed at subverting the host immune response. CD4+ T cells play an important role in controlling Leishmania parasites by providing help in the form of pro-inflammatory cytokines to activate microbiocidal pathways in infected macrophages. However, because these cytokines can also cause tissue damage if over-produced, regulatory immune responses develop, and the balance between pro-inflammatory and regulatory CD4+ T cells responses determines the outcomes of infection. Past studies have identified important roles for pro-inflammatory cytokines such as IFNγ and TNF, as well as regulatory co-inhibitory receptors and the potent anti-inflammatory cytokine IL-10. More recently, other immunoregulatory molecules have been identified that play important roles in CD4+ T cell responses during VL. In this review, we will discuss recent findings about two of these molecules; the NK cell granule protein Nkg7 and the anti-inflammatory cytokine TGFβ, and describe how they impact CD4+ T cell functions and immune responses during visceral leishmaniasis.

Analysis of SIGLEC12 expression, immunomodulation and prognostic value in renal cancer using multiomic databases

Siglecs belong to a family of immune regulatory receptors predominantly found on hematopoietic cells. They interact with Sia, resulting in the activation or inhibition of the immune response. Previous reports have suggested that the SIGLEC12 gene, which encodes the Siglec-XII protein, is expressed in the epithelial tissues and upregulated in carcinomas. However, studies deciphering the role of Siglec-XII in renal cancer (RC) are still unavailable, and here we provide insights on this question. We conducted expression analysis using the Human Protein Atlas and UALCAN databases. The impact of SIGLEC12 on RC prognosis was determined using the KM plotter, and an assessment of immune infiltration with SIGLEC12 was performed using the TIMER database. GSEA was conducted to identify the pathways affected by SIGLEC12. Finally, using GeneMania, we identified Siglec-XII interacting proteins. Our findings indicated that macrophages express SIGLEC12 in the kidney. Furthermore, we hypothesize that Siglec-XII expression might be involved in the increase of primary RC, but this effect may not be dependent on the age of the patient. In the tumour microenvironment, oncogenic pathways appeared to be upregulated by SIGLEC12. Similarly, our analysis suggested that SIGLEC12-related kidney renal papillary cell carcinomas may be more suitable for targeted immunotherapy, such as CTLA-4 and PD-1/PD-L1 inhibitors. These preliminary results suggested that high expression of SIGLEC12 is associated with poor prognosis for RC. Future studies to assess its clinical utility are necessitated.

Immunological signatures from irradiated cancer-associated fibroblasts.

Cancer-associated fibroblasts (CAFs) are abundant and influential elements of the tumor microenvironment (TME), giving support to tumor development in multiple ways. Among other mechanisms, CAFs are important regulators of immunological processes occurring in tumors. However, CAF-mediated tumor immunomodulation in the context of radiotherapy remains poorly understood. In this study, we explore effects of radiation on CAF-derived immunoregulatory signals to the TME. Primary CAF cultures were established from freshly collected human NSCLC lung tumors. CAFs were exposed to single-high or fractionated radiation regimens (1x18Gy or 3x6Gy), and the expression of different immunoregulatory cell-associated and secreted signaling molecules was analyzed 48h and 6 days after initiation of treatment. Analyses included quantitative measurements of released damage-associated molecular patterns (DAMPs), interferon (IFN) type I responses, expression of immune regulatory receptors, and secretion of soluble cytokines, chemokines, and growth factors. CAFs are able to survive ablative radiation regimens, however they enter into a stage of premature cell senescence. Our data show that CAFs avoid apoptosis and do not contribute by release of DAMPs or IFN-I secretion to radiation-mediated tumor immunoregulation. Furthermore, the secretion of relevant immunoregulatory cytokines and growth factors including TGF-β, IL-6, IL-10, TNFα, IL-1β, VEGF, CXCL12, and CXCL10 remain comparable between non-irradiated and radiation-induced senescent CAFs. Importantly, radiation exposure modifies the cell surface expression of some key immunoregulatory receptors, including upregulation of CD73 and CD276. Our data suggest that CAFs do not participate in the release of danger signals or IFN-I secretion following radiotherapy. The immune phenotype of CAFs and radiation-induced senescent CAFs is similar, however, the observed elevation of some cell surface immunological receptors on irradiated CAFs could contribute to the establishment of an enhanced immunosuppressive TME after radiotherapy.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) as a marker of coronary lesion severity in stable coronary artery disease (CAD) patients.

Coronary artery disease (CAD) remains a significant global health concern with considerable high morbidity and mortality and its development is influenced by various genetic and environmental factors. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a vital regulator of low-density lipoprotein receptor (LDLR) metabolism, directly impacting serum cholesterol levels. However, its role in development of CAD is not fully understood. The aim of this study was to assess the association between the level of PCSK9 and coronary lesion severity in patients with CAD. A case-control study using consecutive sampling was conducted among CAD patients at H. Adam Malik General Hospital and Murni Teguh Memorial Hospital, Medan, Indonesia. A total of 200 CAD patients were divided into two groups based on the SYNTAX score: control (score ≤22, n=100) and case (score >22, n=100). Plasma PCSK9 levels were measured from venous blood using quantitative sandwich enzyme immunoassay. The Chi-squared test was used to analyze the data. Our data suggested that PCSK9 level was associated with coronary lesion severity (p<0.001) of which high PCSK9 level was associated with severe coronary lesion. We also found that hypertension (p<0.001), smoking (p=0.072), diabetes (p<0.001), dyslipidemia (p<0.001), obesity (p=0.023), and family history (p=0.001) were associated with lesion severity. Using the receiver operating characteristic (ROC) curve analysis, the cut-off 70.35 ng/mL of PCSK9 had sensitivity 75% and specificity 78% to predict severe coronary lesion. This study highlights that PCSK9 level has moderate sensitivity and specificity to predict the coronary lesion severity among CAD patients.

Sesamin and sesamolin potentially inhibit adipogenesis through downregulating the peroxisome proliferator-activated receptor γ protein expression and activity in 3T3-L1 cells

Sesamin and sesamolin are major sesame lignans that have demonstrated anti-inflammatory, anticancer, and neuroprotective properties and potential benefits in the liver, cardiovascular diseases, and metabolic syndrome. However, despite previous research on their antiobesity effects and underlying mechanisms, a comprehensive investigation of these aspects is still lacking. In this study, we evaluated the regulatory effects of 20 to 80 µM sesamin and sesamolin on adipogenesis in vitro using 3T3-L1 cells as a model cell line. We hypothesized that the lignans would inhibit adipogenic differentiation in 3T3-L1 cells through the regulation of peroxisome proliferator-activated receptor γ (PPARγ). Our data indicate that sesamin and sesamolin inhibited the adipogenic differentiation of 3T3-L1 cells by dose-dependently decreasing lipid accumulation and triglyceride formation. Sesamin and sesamolin reduced the mRNA and protein expression of the adipogenesis-related transcription factors, PPARγ and CCAAT/enhancer-binding protein α, leading to the dose-dependent downregulations of their downstream targets, fatty acid binding protein 4, hormone-sensitive lipase, lipoprotein lipase, and glucose transporter 4. In addition, glucose uptake was dose-dependently attenuated by sesamin and sesamolin in both differentiated 3T3-L1 cells and HepG2 cells. Interestingly, our results suggested that sesamin and sesamolin might directly bind to PPARγ to inhibit its transcriptional activity. Finally, sesamin and sesamolin decreased the phosphorylation of 3 mitogen-activated protein kinase signaling components in differentiated 3T3-L1 cells. Taken together, our findings suggest that sesamin and sesamolin may exhibit antiobesity effects by potentially downregulating PPARγ and its downstream genes through the mitogen-activated protein kinase signaling pathway, offering important insights into the molecular mechanisms underlying the potential antiobesity effects of sesamin and sesamolin.

Disruption of LPA-LPAR1 pathway results in lung tumor growth inhibition by downregulating B7-H3 expression in fibroblasts.

Lysophosphatidic acids (LPAs) belong to a class of bioactive lysophospholipids with multiple functions including immunomodulatory roles in tumor microenvironment (TME). LPA exerts its biological effects via its receptors that are highly expressed in fibroblasts among other cell types. As cancer-associated fibroblasts (CAFs) are a key component of the TME, it is important to understand LPA signaling and regulation of receptors in fibroblasts or CAFs and associated regulatory roles on immunomodulation-related molecules. Cluster analysis, immunoblotting, real-time quantitative-PCR, CRISPR-Cas9 gene editing system, immunohistochemical staining, coculture model, and in vivo xenograft model were used to investigate the effects of LPA-LPAR1 on B7-H3 in tumor promotion of CAFs. In this study, we found that LPAR1 and CD276 (B7-H3) were generally highly expressed in fibroblasts with good expression correlation. LPA induced B7-H3 up-expression through LPAR1, and stimulated fibroblasts proliferation that could be inhibited by silencing LPAR1 or B7-H3 as well as small molecule LPAR1 antagonist (Ki16425). Using engineered fibroblasts and non-small cell lung carcinoma (NSCLC) cell lines, subsequent investigations demonstrated that CAFs promoted the proliferation of NSCLC in vitro and in vivo, and such effect could be inhibited by knocking out LPAR1 or B7-H3. The present study provided new insights for roles of LPA in CAFs, which could lead to the development of innovative therapies targeting CAFs in the TME. It is also reasonable to postulate a combinatory approach to treat malignant fibrous tumors (such as NSCLC) with LPAR1 antagonists and B7-H3 targeting therapies.

A prospective study of circulating estrogen in oral leukoplakia and oral squamous cell carcinoma.

Reports suggested that hormone replacement therapy decreased the incidence of squamous cell carcinoma (SCC) of the oral cavity. The aim of this study was to analyze and quantify the serum 17β-estradiol (E2) level by chemiluminescence immunoassay in four groups, Group I (control group with no habit of tobacco and areca), Group II (control group with a habit of tobacco and areca), Group III (potentially malignant disorder-leukoplakia), and Group IV (oral squamous cell carcinoma (OSCC)). It was the first study to evaluate E2 in four study groups with and without the habit of tobacco. The serum analysis was carried out in Cobas e411 analyzer by electrochemiluminescence immunoassay analysis. As per the Kruskal--Wallis test, statistically significant rise in estradiol levels in Group IV as in comparison to Group III as compared with Groups II and I. This study proved that irrespective of the gender bias, the female sex hormone, estradiol levels were significantly raised in OSCC patients. This study suggests that E2 may play a vital role in determining the patient prognosis in OSCC with tobacco habit. The confounding results of this preliminary study opened up new advents emphasizing the role of E2 in OSCC. The role of E2 in estrogen receptor regulation can also be a subject of study for targeted therapies in improving the patient's prognosis.

Mild internet use is associated with epigenetic alterations of key neurotransmission genes in salivary DNA of young university students

The potentially problematic use of the Internet is a growing concern worldwide, which causes and consequences are not completely understood yet. The neurobiology of Internet addiction (IA) has attracted much attention in scientific research, which is now focusing on identifying measurable biological markers. Aim of this study was to investigate epigenetic and genetic regulation of oxytocin receptor (OXTR), dopamine transporter (DAT1) and serotonin transporter (SERT) genes using DNA obtained from saliva samples of young university students: the Internet Addiction Test (IAT) was administered to evaluate the potential existence and intensity of IA. Significant changes in DNA methylation levels at OXTR, DAT1 and SERT genes were observed in the 30 < IAT < 49 group (mild-risk internet users) compared to the IAT < 29 subjects (complete control of internet use) and IAT > 50 subjects (considered as moderately addicted). Moreover, epigenetic markers were significantly correlated, either directly (for OXTR and DAT1) or inversely (OXTR and DAT1 versus SERT), to the psychometric properties. Our data confirmed the association of OXTR, DAT1 and SERT genes in processes related to behavioural addictions and might be of relevance to suggest possible biological predictors of altered behaviours and the eventual vulnerability to develop an IA. Different other genetic pathways have been suggested to play a role in IA and research is ongoing to better define them, in order to help in the early diagnosis as well as in the development of new potential treatments.