ABSTRACT
PURPOSE OF REVIEW: To review the structure, mechanism of action, and pathophysiology of antibody-drug conjugates (ADCs) used to treat gynecological malignancies associated with ocular adverse effects. RECENT FINDINGS: Recent research shows tisotumab vedotin causes ocular toxicity localized to the conjunctiva, with common adverse effects being conjunctivitis, dry eye, blepharitis, and keratitis. Toxicity is likely due to targeting tissue factor (TF) in the conjunctiva, leading to direct delivery of the cytotoxic payload resulting in apoptosis and bystander killing. Mirvetuximab soravtansine causes blurred vision, keratitis, or dry eye with toxicity often localized in the cornea. Off-target inflammation appears to cause ocular adverse effects, with nonreceptor mediated macropinocytosis by corneal stem cells. SUMMARY: Collaboration between oncologists and ophthalmologists with adherence to mitigation protocols can decrease the risk of ocular adverse events.
ABSTRACT
Human liver-derived metabolically competent HepaRG cells have been successfully employed in both two-dimensional (2D) and 3D spheroid formats for performing the comet assay and micronucleus (MN) assay. In the present study, we have investigated expanding the genotoxicity endpoints evaluated in HepaRG cells by detecting mutagenesis using two error-corrected next generation sequencing (ecNGS) technologies, Duplex Sequencing (DS) and High-Fidelity (HiFi) Sequencing. Both HepaRG 2D cells and 3D spheroids were exposed for 72 h to N-nitrosodimethylamine (NDMA), followed by an additional incubation for the fixation of induced mutations. NDMA-induced DNA damage, chromosomal damage, and mutagenesis were determined using the comet assay, MN assay, and ecNGS, respectively. The 72-h treatment with NDMA resulted in concentration-dependent increases in cytotoxicity, DNA damage, MN formation, and mutation frequency in both 2D and 3D cultures, with greater responses observed in the 3D spheroids compared to 2D cells. The mutational spectrum analysis showed that NDMA induced predominantly A:T â G:C transitions, along with a lower frequency of G:C â A:T transitions, and exhibited a different trinucleotide signature relative to the negative control. These results demonstrate that the HepaRG 2D cells and 3D spheroid models can be used for mutagenesis assessment using both DS and HiFi Sequencing, with the caveat that severe cytotoxic concentrations should be avoided when conducting DS. With further validation, the HepaRG 2D/3D system may become a powerful human-based metabolically competent platform for genotoxicity testing.
Subject(s)
Comet Assay , DNA Damage , Dimethylnitrosamine , High-Throughput Nucleotide Sequencing , Micronucleus Tests , Mutagens , Humans , Dimethylnitrosamine/toxicity , Comet Assay/methods , Micronucleus Tests/methods , Mutagens/toxicity , DNA Damage/drug effects , Spheroids, Cellular/drug effects , Mutagenicity Tests/methods , Cell Culture Techniques , Cell Line , Hepatocytes/drug effects , Mutagenesis/drug effects , Mutation , Dose-Response Relationship, DrugABSTRACT
N-nitrosamine impurities have been increasingly detected in human drugs. This is a safety concern as many nitrosamines are mutagenic in bacteria and carcinogenic in rodent models. Typically, the mutagenic and carcinogenic activity of nitrosamines requires metabolic activation by cytochromes P450 enzymes (CYPs), which in many in vitro models are supplied exogenously using rodent liver homogenates. There are only limited data on the genotoxicity of nitrosamines in human cell systems. In this study, we used metabolically competent human HepaRG cells, whose metabolic capability is comparable to that of primary human hepatocytes, to evaluate the genotoxicity of eight nitrosamines [N-cyclopentyl-4-nitrosopiperazine (CPNP), N-nitrosodibutylamine (NDBA), N-nitrosodiethylamine (NDEA), N-nitrosodimethylamine (NDMA), N-nitrosodiisopropylamine (NDIPA), N-nitrosoethylisopropylamine (NEIPA), N-nitroso-N-methyl-4-aminobutyric acid (NMBA), and N-nitrosomethylphenylamine (NMPA)]. Under the conditions we used to culture HepaRG cells, three-dimensional (3D) spheroids possessed higher levels of CYP activity compared to 2D monolayer cells; thus the genotoxicity of the eight nitrosamines was investigated using 3D HepaRG spheroids in addition to more conventional 2D cultures. Genotoxicity was assessed as DNA damage using the high-throughput CometChip assay and as aneugenicity/clastogenicity in the flow-cytometry-based micronucleus (MN) assay. Following a 24-h treatment, all the nitrosamines induced DNA damage in 3D spheroids, while only three nitrosamines, NDBA, NDEA, and NDMA, produced positive responses in 2D HepaRG cells. In addition, these three nitrosamines also caused significant increases in MN frequency in both 2D and 3D HepaRG models, while NMBA and NMPA were positive only in the 3D HepaRG MN assay. Overall, our results indicate that HepaRG spheroids may provide a sensitive, human-based cell system for evaluating the genotoxicity of nitrosamines.
Subject(s)
Nitrosamines , Humans , Nitrosamines/toxicity , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Carcinogens/toxicity , DNA Damage , Dimethylnitrosamine/toxicity , Mutagens/toxicityABSTRACT
Bisphenols are common chemicals found in plastics and epoxy resins. Over the past decades, many studies have shown that bisphenol A (BPA) is a potential endocrine-disrupting chemical that may cause multisystem toxicity. However, the relative safety of BPA analogues is a controversial subject. Herein, we conducted a review of the reproductive toxicity, neurotoxicity, immunotoxicity, metabolic toxicity and gut microbiome toxicity of the BPA analogues in various species, including Caenorhabditis elegans, zebrafish, turtles, sheep, rodents, and humans. In addition, the mechanisms of action were discussed with focus on bisphenol S and bisphenol F. It was found that these BPA analogues exert their toxic effects on different organs and systems through various mechanisms including epigenetic modifications and effects on cell signaling pathways, microbiome, and metabolome in different species. More research is needed to study the relative toxicity of the lesser-known BPA analogues compared to BPA, both systemically and organ specifically, and to better define the underlying mechanisms of action, in particular, the potentials of disrupting microbiome and metabolism.
Subject(s)
Benzhydryl Compounds/toxicity , Immune System/drug effects , Phenols/toxicity , Animals , Endocrine Disruptors , Gastrointestinal Microbiome/drug effects , Humans , Reproduction/drug effects , Sheep , Sulfones , ZebrafishABSTRACT
The healthy and diverse microbes living in our gut provide numerous benefits to our health. It is increasingly recognized that the gut microbiome affects the host's neurobehavioral state through production of metabolites, modulation of intestinal immunity (e.g., cytokines) and other mechanisms (e.g., gut neuropeptides). By sending the sensed information (e.g., metabolic and immunologic mediators) about the state of the inner organs to the brain via afferent fibers, the vagus nerve maintains one of the connections between the brain and GI tract, and oversees many critical bodily functions (e.g., mood, immune response, digestion and heart rate). The microbiota-gut-brain axis is a bidirectional communication between the gut, its microbiome, and the nervous system. In the present review, the roles of microbiome in neuroendocrine and neuroimmune interactions have been discussed using naturally occurring isoflavones, particularly the phytoestrogen genistein, as there are sex differences in the interactions among the microbiome, hormones, immunity and disease susceptibility. A deep understanding of the mechanisms underlying the interactions among the endocrine modulators, brain, endocrine glands, gut immune cells, vagus nerve, enteric nervous system and gut microbiome will provide important knowledges that may ultimately lead to treatment and prevention of debilitating disorders characterized by deficits of microbiome-neuroendocrine-neuroimmune relationships.
Subject(s)
Gastrointestinal Microbiome/drug effects , Genistein/pharmacology , Animals , Gastrointestinal Tract/physiology , Humans , Neuroimmunomodulation/drug effects , Neurosecretory SystemsABSTRACT
There has been growing interest in the use of human-derived metabolically competent cells for genotoxicity testing. The HepaRG cell line is considered one of the most promising cell models because it is TP53-proficient and retains many characteristics of primary human hepatocytes. In recent years, HepaRG cells, cultured in both a traditional two-dimensional (2D) format and as more advanced in-vivo-like 3D spheroids, have been employed in assays that measure different types of genetic toxicity endpoints, including DNA damage, mutations, and chromosomal damage. This review summarizes published studies that have used HepaRG cells for genotoxicity assessment, including cell model evaluation studies and risk assessment for various compounds. Both 2D and 3D HepaRG models can be adapted to several high-throughput genotoxicity assays, generating a large number of data points that facilitate quantitative benchmark concentration modeling. With further validation, HepaRG cells could serve as a unique, human-based new alternative methodology for in vitro genotoxicity testing.
Subject(s)
DNA Damage , Hepatocytes , Mutagenicity Tests , Humans , Hepatocytes/drug effects , Mutagens/toxicity , Cell Line , Risk AssessmentABSTRACT
PURPOSE: To assess the accuracy and completeness of ChatGPT-generated answers regarding uveitis description, prevention, treatment, and prognosis. METHODS: Thirty-two uveitis-related questions were generated by a uveitis specialist and inputted into ChatGPT 3.5. Answers were compiled into a survey and were reviewed by five uveitis specialists using standardized Likert scales of accuracy and completeness. RESULTS: In total, the median accuracy score for all the uveitis questions (n = 32) was 4.00 (between "more correct than incorrect" and "nearly all correct"), and the median completeness score was 2.00 ("adequate, addresses all aspects of the question and provides the minimum amount of information required to be considered complete"). The interrater variability assessment had a total kappa value of 0.0278 for accuracy and 0.0847 for completeness. CONCLUSION: ChatGPT can provide relatively high accuracy responses for various questions related to uveitis; however, the answers it provides are incomplete, with some inaccuracies. Its utility in providing medical information requires further validation and development prior to serving as a source of uveitis information for patients.
ABSTRACT
Brominated flame retardants are used in many household products to reduce flammability, but often leach into the surrounding environment over time. Hexabromocyclododecane (HBCD) is one brominated flame retardant detected in human blood across the world. HBCD exposure can result in neurological problems and altered lipid metabolism, but to date the two remain unlinked. As lipids constitute â¼50% of brain dry weight, lipid metabolism plays a critical role in neuronal function and homeostasis. To determine the effect of HBCD exposure on brain lipid metabolism, young adult male C57BL/6 mice were exposed to 1 mg/kg HBCD every 3 days for 28 days. Major lipid classes were found to change across brain regions, including the membrane glycerolipids phosphatidylcholine and phosphatidylethanolamine, and sphingolipids such as hexosylceramide. In addition, saturated, monounsaturated, and polyunsaturated fatty acids were enriched within brain lipid species. To understand the source of the brain lipidomic alterations, the blood and liver lipidomes and the cecal microbiome were evaluated. The liver and blood demonstrated changes amongst multiple lipid classes, including triacylglycerol suppression, as well as altered esterified fatty acid content. Significant alterations were also detected in the cecal microbiome, with decreases in the Firmicutes to Bacteriodetes ratio, changes in beta diversity, and pathway alterations associated with metabolic pathways and amino acid biosynthesis. These data demonstrate that HBCD can induce lipidomic alterations across brain regions and organs and supports a potential role of the microbiome in these alterations.
ABSTRACT
PURPOSE: The purpose of this study was to assess the accuracy and completeness of 3 large language models (LLMs) to generate information about antibody-drug conjugate (ADC)-associated ocular toxicities. METHODS: There were 22 questions about ADCs, tisotumab vedotin, and mirvetuximab soravtansine that were developed and input into ChatGPT 4.0, Bard, and LLaMa. Answers were rated by 4 ocular toxicity experts using standardized 6-point Likert scales on accuracy and completeness. ANOVA tests were conducted for comparison between the 3 subgroups, followed by pairwise t-tests. Interrater variability was assessed with Fleiss kappa tests. RESULTS: The mean accuracy score was 4.62 (SD 0.89) for ChatGPT, 4.77 (SD 0.90) for Bard, and 4.41 (SD 1.09) for LLaMA. Both ChatGPT (P = 0.03) and Bard (P = 0.003) scored significantly better for accuracy when compared with LLaMA. The mean completeness score was 4.43 (SD 0.91) for ChatGPT, 4.57 (SD 0.93) for Bard, and 4.42 (SD 0.99) for LLaMA. There were no significant differences in completeness scores between groups. Fleiss kappa assessment for interrater variability was good (0.74) for accuracy and fair (0.31) for completeness. CONCLUSIONS: All 3 LLMs had relatively high accuracy and completeness ratings, showing LLMs are able to provide sufficient answers for niche topics of ophthalmology. Our results indicate that ChatGPT and Bard may be slightly better at providing more accurate answers than LLaMA. As further research and treatment plans are developed for ADC-associated ocular toxicities, these LLMs should be reassessed to see if they provide complete and accurate answers that remain in line with current medical knowledge.
ABSTRACT
BACKGROUND: Most thyroid and parathyroid surgeries are performed by nonfellowship trained, low-volume surgeons with associated higher complication rates. Furthermore, the average number of endocrine procedures performed by general surgery residents is decreasing. While previous studies have documented a lack of general surgery resident confidence in performing these procedures, the specific knowledge gaps in endocrine surgery remain unexplored. METHODS: We conducted semi-structured interviews with surgical residents (clinical PGY3-PGY5) at a high-volume academic center with an endocrine surgery fellowship to discuss their experience, knowledge, and deficits managing patients with surgical thyroid and parathyroid disease. Interviews were audio-recorded, de-identified, and transcribed verbatim. Content analysis was used to identify areas of confidence and knowledge deficits in all phases of care. RESULTS: Overall, 14 trainees participated in the study (50% women, mean PGY: 3.8). Preoperatively, residents were confident with thyroid nodule and primary hyperparathyroidism work-up, but less comfortable with rare conditions. Residents were uncomfortable using ultrasound to identify suspicious lymph nodes or abnormal parathyroid glands. Residents perceived knowledge deficits in the multidisciplinary care and work-up of patients with advanced thyroid cancer. Intraoperatively, most residents were confident performing thyroidectomy and focused parathyroidectomy, but less comfortable performing 4-gland explorations or neck dissections. Several had concern with independently identifying and protecting the recurrent laryngeal nerve or locating parathyroid glands in the setting of negative localization. Residents noted a lack of autonomy in both thyroidectomy and parathyroidectomy. Postoperatively, residents felt confident in the acute management of patients, but identified deficits in long-term management of patients with thyroid cancer or chronic complications. CONCLUSIONS: Despite confidence in managing "bread and butter" cervical endocrine surgery in all phases of care, residents perceive a lack of meaningful autonomy intraoperatively. Further educational endeavors may be required to ensure graduating residents are "practice ready" for straightforward cases they may encounter in practice as a general surgeon. A lack of exposure to complex endocrinopathy even at a high-volume center suggests that comprehensive endocrine surgery fellowship remains critical.
Subject(s)
Clinical Competence , General Surgery , Internship and Residency , Humans , Female , Male , General Surgery/education , Qualitative Research , Interviews as Topic , Education, Medical, Graduate/methods , Thyroidectomy/education , Adult , Endocrine Surgical Procedures/education , Thyroid Diseases/surgeryABSTRACT
AIMS: To determine if cellulose nanofibrils (CNF) have potential applications as food additives. MATERIALS AND METHODS: Male C57BL/6 mice on a Western diet were exposed to CNF for one month at a dose of 30 mg/kg by gavage. Male NOD mice, a model for type 1 diabetes (T1D), were used in a six-month study. KEY FINDINGS: Sequencing analysis of 16S rRNA genes suggested significant changes in gut microbiome of male C57BL/6 mice exposed to CNF. Analysis of functional metagenomics indicated that many of the functional contents that might be altered following CNF ingestion were associated with lipid and carbohydrate processing. Further studies in NOD mice suggested that there were some decreases in the blood glucose levels during the insulin tolerance test and glucose tolerance test following CNF treatment. However, these small decreases were not considered biologically meaningful as there were no significant changes in either the area under the curve or the first-order rate constant for glucose disappearance. Moreover, serum concentrations of cytokines/chemokines including IL-3, IL-12(p70) and the keratinocyte chemoattractant were increased following chronic exposure to CNF. In addition, behavioral studies suggested that the percentage of immobility time during the tail-suspension test was significantly increased following six months of exposure to CNF in NOD mice, signifying an increase in depression-related behavior. SIGNIFICANCE: Collectively, long-term CNF consumption was associated with changes in the ecology of the gut microbiome, immune homeostasis, and possibly energy metabolism and mental health in male NOD mice on a Western diet.
Subject(s)
Gastrointestinal Microbiome , Male , Animals , Mice , Mice, Inbred NOD , Diet, Western/adverse effects , RNA, Ribosomal, 16S/genetics , Depression , Mice, Inbred C57BLABSTRACT
Gastrointestinal cancers are a leading cause of cancer morbidity and mortality worldwide with 4.2 million new cases and 3.2 million deaths estimated in 2020. Despite the advances in primary and adjuvant therapies, patients still develop distant metastases and require novel therapies. Mitogenactivated protein kinase (MAPK) cascades are crucial signaling pathways that regulate many cellular processes, including proliferation, differentiation, apoptosis, stress responses and cancer development. p38 Mitogen Activated Protein Kinases (p38 MAPKs) includes four isoforms: p38α (MAPK14), p38ß (MAPK11), p38γ (MAPK12), and p38δ (MAPK13). p38 MAPK was first identified as a stress response protein kinase that phosphorylates different transcriptional factors. Dysregulation of p38 pathways, in particular p38γ, are associated with cancer development, metastasis, autophagy and tumor microenvironment. In this article, we provide an overview of p38 and p38γ with respect to gastrointestinal cancers. Furthermore, targeting p38γ is also discussed as a potential therapy for gastrointestinal cancers.
Subject(s)
Gastrointestinal Neoplasms , Mitogen-Activated Protein Kinase 11 , Humans , Mitogen-Activated Protein Kinase 11/metabolism , Mitogen-Activated Protein Kinase 12/genetics , Mitogen-Activated Protein Kinase 12/metabolism , Mitogen-Activated Protein Kinase 13/metabolism , Signal Transduction , Gastrointestinal Neoplasms/genetics , p38 Mitogen-Activated Protein Kinases/metabolism , Tumor MicroenvironmentABSTRACT
Epigenetic dysregulation is reported in multiple cancers including Ewing sarcoma (EwS). However, the epigenetic networks underlying the maintenance of oncogenic signaling and therapeutic response remain unclear. Using a series of epigenetics- and complex-focused CRISPR screens, RUVBL1, the ATPase component of NuA4 histone acetyltransferase complex, is identified to be essential for EwS tumor progression. Suppression of RUVBL1 leads to attenuated tumor growth, loss of histone H4 acetylation, and ablated MYC signaling. Mechanistically, RUVBL1 controls MYC chromatin binding and modulates the MYC-driven EEF1A1 expression and thus protein synthesis. High-density CRISPR gene body scan pinpoints the critical MYC interacting residue in RUVBL1. Finally, this study reveals the synergism between RUVBL1 suppression and pharmacological inhibition of MYC in EwS xenografts and patient-derived samples. These results indicate that the dynamic interplay between chromatin remodelers, oncogenic transcription factors, and protein translation machinery can provide novel opportunities for combination cancer therapy.
Subject(s)
Proto-Oncogene Proteins c-myc , Sarcoma, Ewing , Humans , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Protein c-fli-1/genetics , RNA-Binding Protein EWS/genetics , Cell Line, Tumor , Signal Transduction/genetics , Sarcoma, Ewing/genetics , Chromatin , Epigenesis, Genetic/genetics , Peptide Elongation Factor 1/genetics , Peptide Elongation Factor 1/metabolism , Peptide Elongation Factor 1/therapeutic use , ATPases Associated with Diverse Cellular Activities/genetics , ATPases Associated with Diverse Cellular Activities/metabolism , Carrier Proteins/genetics , DNA Helicases/genetics , DNA Helicases/metabolismABSTRACT
Flavopiridol (FVP; Alvocidib), a CDKs inhibitor, is currently undergoing clinical trials for treatment of leukemia and other blood cancers. Our studies demonstrated that FVP also inhibited p38 kinases activities with IC50 (µM) for p38α: 1.34; p38 ß: 1.82; p38γ: 0.65, and p38δ: 0.45. FVP showed potent cytotoxicity in cutaneous T-cell lymphoma (CTCL) Hut78 cells, with IC50 <100 nM. NMR analysis revealed that FVP bound to p38γ in the ATP binding pocket, causing allosteric perturbation from sites surrounding the ATP binding pocket. Kinomic profiling with the PamGene platform in both cell-based and cell-free analysis further revealed dosage of FVP significantly affects downstream pathways in treated CTCL cells, which suggested a need for development of synergistic drugs with FVP to prevent its clinically adverse effects. It led us discover niclosamide as a synergistic drug of FVP for our future in vivo study.
ABSTRACT
Both bisphenol A (BPA) and its analog bisphenol S (BPS) are industrial chemicals that have been used to make certain plastic products applied in chicken farms, including food and water containers. They are endocrine disrupting chemicals (EDCs) with xenoestrogenic activities and affect reproductive success in many ways. It was hypothesized that BPA and BPS could adversely affect the folliculogenesis in chickens due to their disruption of the estrogen responses, using either genomic or non-genomic mechanisms. This study investigated the deleterious effects of BPA and BPS on the ovaries when adult layer chickens were orally treated with these EDCs at 50 µg/kg body weight, the reference dose for chronic oral exposure of BPA established by the U.S. EPA. The chickens in both BPA and BPS-treated groups showed a decreased number of the preovulatory follicles. BPA-treated chickens showed a significant decrease in the diameter of F1. Additionally, both BPA and BPS treatments increased the infiltrations of lymphocytes and plasma cells in ovaries. Moreover, it was found that the ovaries of BPS-treated chickens weighed the most among the groups. RNA sequencing and subsequent pathway enrichment analysis of differentially expressed genes revealed that both BPA- and BPS-treatment groups showed significant changes in gene expression and pathways related to reproduction, immune function and carcinogenesis. Taken together, both BPA and BPS are potentially carcinogenic and have deleterious effects on the fertility of laying chickens by inducing inflammation, suggesting that BPS may not be a safe replacement for BPA.
Subject(s)
Benzhydryl Compounds/toxicity , Endocrine Disruptors/toxicity , Ovarian Follicle/drug effects , Phenols/toxicity , Sulfones/toxicity , Animals , Chickens , Estrogens , Female , Fertility , Gene Expression/drug effects , Ovarian Follicle/growth & development , Ovary/drug effects , ReproductionABSTRACT
We describe here for the first time a lipid-binding-domain (LBD) in p38γ mitogen-activated protein kinase (MAPK) involved in the response of T cells to a newly identified inhibitor, CSH71. We describe how CSH71, which binds to both the LBD and the ATP-binding pocket of p38γ, is selectively cytotoxic to CTCL Hut78 cells but spares normal healthy peripheral blood mononuclear (PBMC) cells, and propose possible molecular mechanisms for its action. p38γ is a key player in CTCL development, and we expect that the ability to regulate its expression by specifically targeting the lipid-binding domain will have important clinical relevance. Our findings characterize novel mechanisms of gene regulation in T lymphoma cells and validate the use of computational screening techniques to identify inhibitors for therapeutic development.
Subject(s)
Adenosine Triphosphate/metabolism , Lymphoma, T-Cell, Cutaneous/metabolism , Mitogen-Activated Protein Kinase 12/metabolism , Skin Neoplasms/metabolism , Antineoplastic Agents/therapeutic use , Gene Expression Regulation, Neoplastic , Humans , Lymphoma, T-Cell, Cutaneous/drug therapy , Lymphoma, T-Cell, Cutaneous/genetics , Signal Transduction , Skin Neoplasms/drug therapy , Skin Neoplasms/geneticsABSTRACT
Lymph nodes are important front-line defense immune tissues, which also act against inflammatory diseases and cancer. Lymph nodes undergo extensive upheavals within newly formed germinal centers (GCs) when exposed to antigens, the molecular mechanisms of which remain elusive. Recently, p38γ was identified as an important target for multiple cancers, including cutaneous T-cell lymphoma (CTCL). We previously observed that p38γ is overexpressed in CTCL versus normal cells, but it is not clear if p38γ is expressed in B or T lymphocytes of GCs of patients in response to a stress such as cancer. Therefore, in this study, we obtained non-metastatic reactive lymph nodes adjacent to cancer lesions (colorectal adenocarcinoma), then performed multicolor immunohistochemical staining for p38γ and other relevant markers. We observed for the first time that p38γ was expressed in the light zone of activated B cells and T helper cells in GCs, whereas DNA-methyltransferase 1 (DNMT1), a marker for GC B cells, was highly expressed in centrocytes and in the dark zone of GCs. This inverse relationship suggests a novel function for p38γ in T cells that cross-talk to B cells in response to stress.
ABSTRACT
The immunotoxicant bisphenol A (BPA) may produce toxic effects on organs and systems, in part, by altering the secretion of cytokines and chemokines. However, systematic studies of the effects of BPA, let alone of its analogs and in cases when there are interactions with other chemicals, on innate immunity and cytokine modulation are limited. The objectives of this study were to investigate the immunomodulatory effects of: (1) BPA and its analogs, BPS and BPAF; and (2) the interaction between BPA and genistein (GEN), a partial estrogen agonist or antagonist. BPA, BPS, and BPAF were incubated with PMA-differentiated-U937 cells (a widely used cell line for primary human macrophages) at concentrations of 0, 0.1, 1, 10, 100 µM for up to 96 h. BPA (0, 0.1, 1, 10 µM) and GEN (0, 1, 10 µM) were also applied at various combinations. Cell viability and 30 cytokines/chemokines were measured. The results showed that the cell viability-inhibiting effect of these three bisphenols was BPAF > BPA > BPS. At 0.1 µM, BPA and BPAF generally increased the secretion of cytokines/chemokines, while BPS had minimal effects. All three bisphenols generally suppressed the secretion of cytokines/chemokines at 1 µM, while increased their secretion at 10 µM. The most increased cytokines/chemokines were interferon (IFN)-γ, interleukin (IL)-1RA, IL-8 and MIP-1ß, and the most decreased was IL-10. GEN increased cell viability at low BPA concentrations but had no effect when BPA levels were high. In general, GEN attenuated the BPA-induced secretion of cytokines/chemokines but enhanced it at low BPA concentrations. In conclusion, this study showed that BPA, BPS, and BPAF were immunotoxic to macrophages: BPS was the least toxic, while BPAF was the most toxic. Further, GEN reversed suppressive effects on macrophages that resulted from exposure to high concentrations of BPA and produced synergetic effects with BPA at low concentrations.
Subject(s)
Air Pollutants, Occupational/toxicity , Benzhydryl Compounds/toxicity , Genistein/pharmacology , Inflammation/immunology , Macrophages/drug effects , Phenols/toxicity , Sulfones/toxicity , Cell Survival , Chemokines/metabolism , Cytokines/metabolism , Drug Interactions , Estrogens/metabolism , Humans , Immunity, Innate/drug effects , Macrophages/immunology , U937 CellsABSTRACT
Diabetes contributes considerably to the health disparities in the Aboriginal population. To address the lack of Aboriginal-specific diabetes education tools, Feltman was designed for health professionals to deliver diabetes prevention and management information. This qualitative study aims to explore how this resource was used and its perceived effect on diabetes prevention and management in Victorian Aboriginal communities. Convenience sampling was used to recruit 18 participants (n=6 were Aboriginal) who had attended Feltman training between 2010 and 2016. Semi-structured interviews conducted via telephone or face-to-face were audio-recorded, transcribed and analysed via content analysis. Content analysis identified three main categories regarding Feltman: (1) utilisation in Aboriginal and mainstream health services; (2) as a comprehensive, engaging tool that supports understanding of diabetes; and (3) the barriers and challenges to Feltman's use. Overall, Feltman was regarded as a culturally appropriate diabetes education tool that is visual, tactile, engaging, supportive of health literacy and perceived to enhance Community members' understanding of diabetes prevention and management. This is the first study to provide insight into Feltman's implementation; adding to the evidence-base for Aboriginal-specific diabetes education tools.
Subject(s)
Culturally Competent Care/methods , Diabetes Mellitus/therapy , Health Education/methods , Health Personnel , Health Services, Indigenous , Native Hawaiian or Other Pacific Islander , Australia , Cultural Competency , Diabetes Mellitus/prevention & control , Humans , Interviews as Topic , Qualitative ResearchABSTRACT
Current cutaneous T-cell lymphoma (CTCL) therapies are marked by an abbreviated response, subsequent drug resistance, and poor prognosis for patients with advanced disease. An understanding of molecular regulators involved in CTCL is needed to develop effective targeted therapies. One candidate regulator is p38γ, a mitogen-activated protein kinase crucial for malignant T-cell activity and growth. p38γ gene expression is selectively increased in CTCL patient samples and cell lines but not in healthy T cells. In addition, gene silencing of p38γ reduced CTCL cell viability, showing a key role in CTCL pathogenesis. Screening p38γ inhibitors is critical for understanding the mechanism of CTCL tumorigenesis and developing therapeutic applications. We prioritized a potent p38γ inhibitor (F7, also known as PIK75) through a high-throughput kinase inhibitor screen. At nanomolar concentrations, PIK75, a multiple kinase inhibitor, selectively killed CD4+ malignant CTCL cells but spared healthy CD4+ cells; induced significant reduction of tumor size in mouse xenografts; and effectively inhibited p38γ enzymatic activity and phosphorylation of its substrate, DLGH1, in CTCL cells and mouse xenografts. Here, we report that PIK75 has a potential clinical application to serve as a scaffold molecule for the development of a more selective p38γ inhibitor.