GATA3 Expression Research Articles

Effects of different concentrations of reversine to enhance conversion of dedifferentiated fat cells into mature cardiomyocytes

Background There is an essential need for cardiomyocyte regeneration among patients with heart failure. Transplantation of dedifferentiated fat (DFAT) cells may lead to an improvement of cardiomyocyte regeneration among heart failure patients. We believe that DFAT cells are promising candidate cell sources for cardiac regeneration. However, the pathway underlying how DFAT cells of the adipose lineage differentiate into mature cardiomyocytes isn’t fully understood. Methods We conducted an experimental laboratory study on isolated DFAT cells from adipose tissue of healthy adults. Then, we treated cells with different concentrations of reversine (10, 20 and 40 nM), and performed RNA extraction and cDNA synthesis. Next, we used a ceiling culture method based on the buoyancy properties of mature lipid-filled adipocytes. Stemness expression (Octamer-binding transcription factor 4 [Oct4], brachyury, Fetal liver kinase 1 [Flk-1]) was quantified by reverse transcription-quantitative (RT-q)PCR, while cardiomyocyte expression (Transcription factor GATA-4 [GATA4] and cardiac troponin T [cTnT]) was quantified by immunocytochemistry. Results ANOVA with Tukey’s post-hoc found that 10 nM reversine increased greater Flk-1 expression compared to the control group (MD: 5.037 + 0.998; p < 0.001), but there were no significant changes among Oct4 (MD: 0.013 + 1.244; p = 0.99) and brachyury expression (MD: 0.157 + 0.084; p = 0.252). Kruskal-Wallis revealed that the expression of GATA4 (1.65 [0.41-1.98] to 0.015 [0.007-0.034]; p =0.017) reduced significantly from day 7 until day 21 and cTnT (5.07 [6.62-8.91] to 8.22 [6.81-9.40]; p= 0.001) increased significantly from day 7 until day 21. Conclusions Reversine could increase the expression of Flk-1, but it was unable to stimulate the expression of Oct4 and brachyury related to stem cell-ness. An optimal concentration of 10 nM reversine may have the greatest effect on enhancing the differentiation of DFAT cells into mature cardiomyocytes, as indicated by higher cTnT expression between cells.

Abstract 4231: A biobank of bladder cancer organoids as a platform for screening new therapeutic approaches

Abstract In patients with bladder cancer (BC) immune therapies have recently demonstrated an improvement for overall survival rates compared to chemotherapy alone. However, several challenges persist and it remains an unmet need to develop novel therapeutic strategies. Organoids have emerged as a promising animal-free tool revealing patients’ heterogeneity and allowing large preclinical therapeutic screening. Urosphere developed a BC organoids biobank with phenotypic, pharmacological and molecular characterization. The aim of this study was to demonstrate the relevance of our organoids models and their use for validation of therapeutic approaches such as targeted or CAR-T cell therapies using EGFR as target. Molecular characterization of the organoids was performed by exome and whole transcriptome sequencing. Cell architecture and differentiation were assessed by labeling cytokeratins (CK) 5, 17 and 20, and uroplakin 3 (UPK3). Proliferation and tumor status were validated with Ki67 and GATA3, respectively. To evaluate targeted-therapy, organoids were treated with erlotinib for 5 days and cell viability was measured with CellTiter-Glo3D® (CTG) assay. To validate CAR-T cell approach, organoids were co-cultured with anti-EGFR or control anti-CD19 CAR-T cells at 4 effector:target ratios. Cell viability was measured with CTG and Caspase-Glo® 3/7 3D assays. Pro-inflammatory and granzyme B release were analyzed by Luminex® assay. Phenotypically, organoids showed proliferating structures whose tumor status was confirmed by GATA3 expression. Cellular heterogeneity present in original tumors was also found, with differential expression of CKs showing the presence of basal (CK5/CD17) and/or differentiated superficial (CK20/UPK3) cells. Organoids from 2 models with high transcriptomic EGFR expression were selected and protein expression was confirmed by immunofluorescence. For targeted therapy, erlotinib presented significant efficacy in both models with a better activity in the model presenting the highest EGFR expression. After 48h of co-culture with anti-EGFR CAR-T cells, a decrease of cell viability associated with an increase of apoptosis was observed. After 72h of co-culture, an increase in the secretion of pro-inflammatory cytokines (IFN-γ and TNF-α) and granzyme B by anti-EGFR CAR-T cells was also observed. In co-cultures with organoids higher expressing EGFR, CAR-T cells activation appeared higher compared to those co-cultured with organoids lower expressing EGFR. Organoids reproduce characteristics of the tumor from which they are derived, making them a predictive preclinical model. In an EGFR targeting approach, the use of organoids to evaluate both targeted- and CAR-T cell therapies was validated with concordant results. This robust translational model is fully transposable to other therapeutic approaches, whether in a traditional culture model or in a co-culture system. Citation Format: Emilie Decaup, Claire Béraud, Anne Sophie Bajeot, Xavier Gamé, Nicolas Monjotin, Pascal Rischmann, Philippe Lluel, Mathieu Roumiguié. A biobank of bladder cancer organoids as a platform for screening new therapeutic approaches [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4231.

Abstract 5220: Reduced expression of Glutathione peroxidase 2 (GPX2) is an independent predictor of poor prognosis in muscle-invasive urothelial carcinoma of the bladder

Abstract Background: The Glutathione peroxidase 2 (GPX2) is a selenium-dependent glutathione peroxidase with a pivotal role in removing potentially harming reactive oxygen species (ROS) from cells by catalyzing the reduction process of hydrogen peroxide to water. GPX2 is strongly expressed in normal urothelium but can be reduced in urothelial cancer. The aim of the study was to evaluate the potential clinical significance of GPX2 expression in urothelial bladder cancer. Design: GPX2 was analyzed by immunohistochemistry (IHC) in more than 2,500 urothelial bladder carcinomas in a tissue microarray format. Follow-up data were available for more than 600 patients with muscle-invasive disease. Results: GPX2 staining occurred in 67.5% of urothelial carcinomas including 11.4% with weak, 11.9% with moderate, and 44.2% with strong staining. While GPX2 staining was always strong in normal urothelium, it decreased markedly during grade and stage progression. Within pTa tumors, GPX2 positivity continuously decreased from pTaG2 low grade (99.4% positive) to pTa G2 high grade (97.2% positive) and to pTa G3 (90.5%; p=0.0013) while there was a marked further drop of GPX2 positivity from pTaG3 to muscle-invasive cancers (56.6%; p<0.0001 for pT2-4 vs. pTa G3). Within pT2-4 carcinomas, low or absent GPX2 staining was significantly linked to poor overall survival (p=0.0140), V1 (p<0.0001), L1 (p=0.0014), and high grade (p=0.0091), but statistically unrelated to pT and pN. In a multivariate analysis, the prognostic impact of reduced GPX2 expression (p=0.0081) was independent of pT (p<0.0001) and pN (p<0.0001) in pT2-4 tumors. GPX2 expression loss was inversely related to the expression of the luminal subtype markers GATA3 (p<0.0001), uroplakin 1b (p<0.0001) and cytokeratin 20 (p<0.0001) in pT2-4 carcinomas. Conclusion: GPX2 expression loss is a common event during bladder cancer progression which is strongly associated with poor prognosis in patients with pT2-4 urothelial carcinomas. GPX2 expression measurement - optimally together with other markers - could be useful for clinical risk assessment of bladder cancer patients. Citation Format: Henning Plage, Sebastian Hofbauer, Kira Furlano, Sarah Weinberger, Antonia Franz, Annika Fendler, Joachim Weischenfeldt, Florian Roßner, Simon Schallenberg, Sefer Elezkurtaj, Martina Kluth, Andreas H. Marx, Henrik Samtleben, Margit Fisch, Marcin Slojewski, Krystian Kaczmarek, Thorsten Ecke, Stefan Koch, Nico Adamini, Ronald Simon, Guido Sauter, Henrik Zecha, Tobias Klatte, Sarah Minner, David Horst, Thorsten Schlomm, Michael Rink, Maximilian Lennartz. Reduced expression of Glutathione peroxidase 2 (GPX2) is an independent predictor of poor prognosis in muscle-invasive urothelial carcinoma of the bladder [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5220.

Abstract 1772: A naturally occurring canine model of peripheral T-cell lymphoma, not otherwise specified

Abstract Despite being the most common subtype of human peripheral T-cell lymphoma (PTCL), PTCL-not otherwise specified (PTCL-NOS) remains a poorly understood diagnosis of exclusion with poor survival times and treatment responses. Canine PTCL clinically and immunophenotypically resembles human PTCL-NOS, and PTCL is more common in dogs than humans, leading to their interest as a naturally occurring preclinical model. Canine models of cancer offer several unique advantages: in contrast to traditional rodent models, these are spontaneous tumors in genetically diverse and immunocompetent animals living in a shared environment with humans, but relative to their human counterparts, they offer accelerated lifespans with shorter clinical courses of disease. Here, we analyzed the gene expression profile of 96 canine CD4+ PTCLs to determine similarities to human PTCL-NOS and investigate a possible cell of origin. Bulk RNA-seq was performed on lymph node aspirates of 96 cases of canine CD4+ PTCL diagnosed by flow cytometry and sorted CD4+ nodal lymphocytes and CD4+ thymocytes from healthy control dogs. Raw reads were aligned to the Ensembl canine reference genome (ROS_Cfam_1.0) and tabulated. Data normalization and differential expression analysis was conducted with DESeq2, and differentially expressed genes were compared to human PTCL-NOS and various stages of T-cell development via gene set enrichment analyses (GSEA). Global gene expression in canine CD4+ PTCL was analogous to that of human PTCL-NOS (NES = 2.3, p < 0.001). Additionally, canine CD4+ PTCL had increased expression of GATA3 (log2fc = 1.9, padj = 6.5e-07) and was enriched for gene signatures associated with downregulation of PTEN (NES = 1.7, p = 0.0001) and upregulation of PI3K/AKT/mTOR signaling (NES = 1.5, padj = 0.0007), resembling the more aggressive human GATA3-PTCL subtype. Canine CD4+ PTCL was also enriched for human and murine gene signatures associated with early thymocyte progenitor cells and had increased expression of genes of immaturity, including CD34 (log2fc = 7.8, padj = 2.6e-14), KIT (log2fc = 3.3, padj = 7.7e-05), and CCR9 (log2fc = 4.8, padj = 3.9e-11), although surface CD34 expression is not detected by flow cytometry. These findings were confirmed when we compared the canine PTCL gene expression programs to a canine single cell transcriptomic atlas of hematopoietic precursors and T cells across canine bone marrow, thymic, and lymph node tissues. Canine CD4+ PTCL cells were significantly (padj < 0.05) enriched for gene signatures associated with early thymic and bone marrow precursors (NES 1.3-2.1), and negatively enriched for gene signatures associated with naïve nodal CD4+ T cells (NES = -3.2, padj = 0.006). In conclusion, the gene expression profile of canine CD4+ PTCL resembles human PTCL-NOS, supporting its potential as a naturally occurring preclinical model, and a subset of these neoplasms may arise from a thymic precursor cell of origin. Citation Format: Eileen Owens, Adam Harris, Anne Avery. A naturally occurring canine model of peripheral T-cell lymphoma, not otherwise specified [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1772.

Lack of ATP2B1 in CD4+ T Cells Causes Colitis.

The ATP2B1 gene encodes for a calcium pump, which plays a role in removing Ca2+ from cells and maintaining intracellular Ca2+ homeostasis. Reduction of the intracellular Ca2+ concentration in CD4+ T cells is thought to reduce the severity of colitis, while elevation of Ca2+ in CD4+ T cells induces T cell hyperactivity. Our aim was to clarify the role of ATP2B1 in CD4+ T cells and in inflammatory bowel disease development. A murine CD4+ T cell-specific knockout (KO) of ATP2B1 was created using a Cre-loxP system. CD4+ T cells were isolated from thymus, spleen, and blood using fluorescence-activated cell sorting. To quantify messenger RNA levels, quantitative real-time polymerase chain reaction was performed. Although the percentages of CD4+ T cells in both KO mouse spleen and blood decreased compared with those of the control samples, both T-bet (a T helper 1 [Th1] activity marker) and GATA3 (a Th2 activity marker) expression levels were further increased in KO mouse blood CD4+ T cells (vs control blood). Diarrhea and colonic wall thickening (with mucosal changes, including crypt distortion) were seen in KO mice but not in control mice. Prior to diarrhea onset, the KO mouse colon length was already noted to be shorter, and the KO mouse stool water and lipid content were higher than that of the control mice. Tumor necrosis factor α and gp91 expressions were increased in KO mouse colon. Lack of ATP2B1 in CD4+ T cells leads to Th1 and Th2 activation, which contributes to colitis via elevation of tumor necrosis factor α and oxidative stress.

GATA6 inhibits the biological function of non-small cell lung cancer by modulating glucose metabolism

PurposeThis study aims to explore the role of GATA6 in lung cancer, with a focus on its impact on metabolic processes.MethodsWe assessed GATA6 expression in lung cancer tissues and its association with patient prognosis. In vitro cell function experiments were conducted to investigate the effects of altered GATA6 levels on lung cancer cell proliferation and migration. Mechanistic insights were gained by examining GATA6's influence on glucose metabolism-related genes, particularly its effect on c-Myc mRNA expression.ResultsOur study revealed significant down-regulation of GATA6 in lung cancer tissues, and this down-regulation was strongly correlated with unfavorable patient prognosis. Elevating GATA6 levels effectively inhibited the proliferation and migration of lung cancer cells in our cell function experiments. Mechanistically, we found that GATA6 suppressed the expression of c-Myc mRNA, impacting genes related to glucose metabolism. As a result, glucose uptake and metabolism in lung cancer cells were disrupted, ultimately impeding their malignant behaviors.ConclusionOur study provides crucial insights into the metabolic regulation of GATA6 in lung cancer cells. These findings have the potential to offer a solid theoretical foundation for the development of novel clinical treatments for lung cancer.

Correlation of histopathologic findings with clinical predictors of disease recurrence and progression to vulvar carcinoma in patients with differentiated vulvar intraepithelial neoplasia (dVIN)

ObjectiveTo evaluate predictors of recurrence and the risk of progression to carcinoma in patients with dVIN. Methods36 self-identified White patients with dVIN from 2011 to 2022 were identified. Demographics, treatment and clinical course were abstracted. Histopathologic features and IHC stains were reviewed by 2 subspecialty pathologists. Standard statistical analyses were applied. ResultsMedian cohort age was 70 years (range 39–91). Median follow-up was 29.5 months (range 1–123). All patients were Caucasian. 67% had lichen sclerosus (LS) adjacent to dVIN. 56% of patients had recurrent dVIN a median of 11 months from diagnosis. 14 patients had invasive squamous cell carcinoma of the vulva (SCCV) during the study period: 9 (25%) with synchronous dVIN, 5 (14%) developed SCCV after a median of 21.5 months (range 8–57). Patients treated with surgery were more likely to have recurrent/persistent dVIN (p = 0.04) and synchronous or progression to SCCV (p = 0.02) than patients treated with topical therapy. Excluding 9 women with synchronous SCCV, no initial treatment (observation, topical therapy, surgery) was superior at preventing recurrent/ progressive disease in isolated dVIN. Mutation-type p53 expression was identified in 18 (64%) and aberrant GATA3 staining/expression in 20 (56%) of cases. Aberrant GATA3 expression was associated with a higher frequency of synchronous/progression to SCCV (p < 0.05). ConclusiondVIN has an aggressive clinical course in white patients with a high risk of recurrence/persistence and synchronous/progression to SCCV despite treatment. Close surveillance with a low threshold for additional biopsies is warranted. P53 and GATA3 IHC stains may be useful markers of disease outcome.

Premature Classification of Early-stage Endometrioid Ovarian Carcinoma With Mesonephric-like Differentiation as Mesonephric-like Adenocarcinoma.

Ovarian mesonephric-like adenocarcinoma (MLA) is a rare tumor with potential origins in endometriosis and Müllerian-type epithelial tumors. The morphologic patterns of MLA overlap with those of endometrioid ovarian carcinoma (EnOC). We speculated that a subset of MLAs would be classified as EnOCs. In this study, we attempted to identify MLAs from malignant endometrioid tumors. Given that the study patients with MLAs had both endometrioid-like and mesonephric-like morphologies, we defined mesonephric-like differentiation (MLD) as an endometrioid tumor with focal or diffuse MLA morphology and immunophenotype. Twelve patients exhibited mesonephric-like morphologic patterns. Immunohistochemistry analysis for CD10, TTF-1, estrogen receptor (ER), GATA3, calretinin, and PAX8 expression was done using whole-section slides. Two patients without the MLA immunophenotype were excluded. Ten patients with EnOCs with MLD (8.3%) were identified from a cohort of 121 patients with malignant endometrioid tumors. All 10 patients were positive for TTF-1 and/or GATA3. Most patients were ER-negative. Morphologically, MLD was associated with papillary thyroid carcinoma-like nuclei, flattened cells, tubular, nested, reticular, or glomeruloid architecture, and infiltrative growth. All 10 patients had pre-existing endometriosis and/or adenofibromas. Among the EnOCs with MLD, 5 had coexisting components such as EnOC grade 1 [(G1), cases 4, 7, and 9], mucinous borderline tumor (case 1), and dedifferentiated carcinoma (case 10), with distinct borders between EnOC with MLD and the other components. Nine of the 10 MLA patients (90%) harbored KRAS hotspot mutations. In addition, 4 patients harboring other components shared common KRAS hotspot mutations. No significant prognostic differences were observed between patients with and without MLD. Based on our findings, we suggest that EnOC with MLD, especially in the early stages and without high-grade components, should be considered a subtype of EnOC. Overtreatment should be avoided in such patients, particularly in the early stages. In this study, as the characteristics between EnOC with MLD and MLA were not distinguishable, we considered both conditions to be on the same spectrum. EnOCs with MLD exhibit the MLA phenotype during disease progression and are prematurely classified as MLA. Nevertheless, more patients with EnOC who have MLD/MLA are required for a more robust comparison between conventional EnOC according to staging and grading.

Expression Patterns of GATA3 in Classical Hodgkin Lymphoma: A Clinico-Pathological Study.

GATA3 is a transcription factor involved in T-cell maturation and has been previously shown to be aberrantly overexpressed in malignant Hodgkin and Reed-Sternberg (HRS) cells of classical Hodgkin lymphoma (cHL). However, the immunophenotypes of the cell types expressing GATA3 have not been precisely characterized so far in cHL tissues. In this single-center retrospective cohort study we analyzed the expression patterns of GATA3 alone and in combination with B, T, NK or macrophage-associated markers in 73 cases with newly diagnosed cHL and investigated for a possible correlation with clinical and laboratory parameters. Immunohistochemistry (single and double) was performed using GATA3 alone and in combination with CD20, CD3, CD56, CD68, CD30 or CD15. Clinical and laboratory parameters were collected and correlated with the expression of GATA 3. GATA3 nuclear expression was found in HRS cells in 39/73 (54%) cases of cHL. The Nodular Sclerosis (NS) subtype showed the highest positivity rate (35/56, 63%), followed by mixed cellularity (MC; 4/14, 29%) and lymphocyte rich (LR; 0/3). Double immunostainings showed that GATA3 was expressed by CD30+ or CD15+ HRS cells and a few CD3+ T-cells, whereas GATA3 expression was not detected in CD20, CD56 or CD68+ cells. GATA3-negative cHL was significantly associated with unfavorable prognostic factors such as older age at diagnosis and increased levels of serum β2-microglobulin. The heterogenous expression patterns of GATA3 in HRS cells that were observed in a substantial proportion of cHL, mainly in the NS subtype, further support the biological heterogeneity of cHL.

Prevalence and Pattern of GATA3 Immunohistochemical Expression in Female Genital Tract Adenocarcinomas.

GATA3 immunohistochemistry has been described as a highly sensitive marker in determining carcinomas of breast and urothelial origin. In the gynecologic system, it can be used as a marker to diagnose mesonephric or mesonephric-like carcinomas and trophoblastic tumors. The present study was performed to determine the diagnostic value of GATA3 in gynecological adenocarcinomas. A total of 187 samples from different types of endometrial, endocervical, and ovarian carcinomas were analyzed for intensity and percentage of GATA3 expression in tumor cells. The relationship between GATA3 expression and clinicopathological parameters was investigated. A total of 187 patients including 101 ovarian, 77 endometrial, and 9 endocervical adenocarcinomas were investigated. Weak and focal expression of this marker was observed in 5. 1% (4/77) endometrial, 12.9% (13/101) ovarian, and 11.1% (1/9) endocervical adenocarcinomas. The mean H score in all subtypes was less than 10.6 (2-35). There was no statistically significant correlation between GATA3 expression in tumor cells with clinical stage, and tumor recurrence or metastasis. GATA3 is infrequently, weak, or focally expressed in most of the common gynecological adenocarcinomas.

Mesenchymal Stem Cell Transplantation Has a Regenerative Effect in Ischemic Myocardium: An Experimental Rat Model Evaluated by SPECT-CT Assessment.

The regeneration of myocardial tissue and the improvement of myocardial activity after ischemia is one of the major areas of interest in cardiovascular research. We developed a novel experimental rat model and used it to examine the effect of mesenchymal stem cell transplantation (MSCT) on myocardial ischemia evaluated by SPECT-CT and immunohistochemistry. An open thoracotomy took place for forty adult female Wistar rats with (n = 30) or without (n = 10) surgical ligation of the left anterior descending coronary artery (LAD) in order to cause myocardial ischemia. Myocardial viability was evaluated via SPECT/CT 7 days before surgery, as well as at 7 and 14 days post-surgery. At day 0, 15 animals received homologous stem cells injected at the ischemic myocardium area. A SPECT/CT evaluation showed decreased activity of the myocardial cells in the left ventricle one week post-infarction. Regeneration of the ischemic myocardium fifteen days post-infarction was recorded only in animals subjected to stem cell transplantation. These findings were also confirmed by histology and immunohistochemical analysis, with the significantly higher expression of GATA4 and Nkx2.5. The positive effect of mesenchymal stem cell transplantation in the ischemic myocardium was recorded. The application of SPECT-CT allowed a clear evaluation of both the quality and quantity of the living myocardium post-infarction, leading to a new approach in the research of cardiovascular diseases. From a clinical perspective, MSCT may be beneficial when accompanied by myocardial revascularization procedures.

Expression of programmed cell death ligand 1 and clinicopathological and immunological characteristics in fumarate hydratase-deficient renal cell carcinoma

Objective: To investigate the expression of programmed cell death ligand 1 (PD-L1), clinicopathologic features, immunohistochemical expression and molecular characteristics in fumarate hydratase (FH)-deficient renal cell carcinoma and to explore the potential application of immunotherapy in the patients. Methods: There were six patients with FH-deficient renal cell carcinoma treated at the First Affiliated Hospital of Fujian Medical University between January 2020 and October 2022. The clinical data, histological morphology, immunophenotype, PD-L1 expression and next-generation sequencing results were tabulated and analyzed. Results: There were 6 patients, all male, age ranged from 37 to 72 years (mean 45.7 years). Four cases were high-grade (WHO/ISUP grade3-4) with 2 or more histologic patterns, including papillary (most common), glandular, tubular, vesicular, ethmoid, nest-like, cystic and solid structures. Two cases were low-grade which showed nest-like, glandular, or tubular arrangement with eosinophilic flocculent cytoplasm and small intracellular vacuoles. Immunohistochemical analysis revealed strong expression of 2SC in all 6 cases, negative expression of FH in 5 cases, and positive expression of GATA3 in 5 cases. In high-grade cases, the mean values of CD4 and CD8 positive T-lymphocytes in advanced tumor invasion were 180.3/mm2 and 130.5/mm2, respectively. PD-L1 combined positive scores (CPS) were 20, 50, 5 and 30, respectively. The Ki-67 proliferative index were 20%, 20%, 10% and 30%, respectively. In low-grade cases, the mean values of CD4 and CD8 positive T-lymphocytes were 123.0/mm2 and 100.5/mm2, respectively. The PD-L1 CPS score was 1, and the Ki-67 proliferation index was 3%. High-throughput sequencing showed FH gene somatic mutation in 3 cases, FH gene germline mutation in 2 cases, and FH gene mutation was not detected in one case. Conclusion: FH-deficient renal cell carcinoma is more commonly high-grade than low grade. FH and 2SC are immunohistochemical markers used in the diagnosis of FH-deficient renal cell carcinoma, and GATA3 positivity is supportive of the diagnosis. The tumor infiltration of high-grade FH-deficient renal cell carcinoma shows an increase in CD4 and CD8 positive T-lymphocytes, and high expression of PD-L1; thus, anti-PD-L1 immunotherapy can be used as a treatment option.

MiR-1202 acts as anti-oncomiR in myeloid leukaemia by down-modulating GATA-1S expression.

Transient abnormal myelopoiesis (TAM) is a Down syndrome-related pre-leukaemic condition characterized by somatic mutations in the haematopoietic transcription factor GATA-1 that result in exclusive production of its shorter isoform (GATA-1S). Given the common hallmark of altered miRNA expression profiles in haematological malignancies and the pro-leukaemic role of GATA-1S, we aimed to search for miRNAs potentially able to modulate the expression of GATA-1 isoforms. Starting from an in silico prediction of miRNA binding sites in the GATA-1 transcript, miR-1202 came into our sight as potential regulator of GATA-1 expression. Expression studies in K562 cells revealed that miR-1202 directly targets GATA-1, negatively regulates its expression, impairs GATA-1S production, reduces cell proliferation, and increases apoptosis sensitivity. Furthermore, data from TAM and myeloid leukaemia patients provided substantial support to our study by showing that miR-1202 down-modulation is accompanied by increased GATA-1 levels, with more marked effects on GATA-1S. These findings indicate that miR-1202 acts as an anti-oncomiR in myeloid cells and may impact leukaemogenesis at least in part by down-modulating GATA-1S levels.

Vitamin D improves autoimmune diseases by inhibiting Wnt signaling pathway.

In this study, we investigated the development of the Wnt signaling pathway in vitamin D (VitD) to improve systemic lupus erythematosus in mice to breakthrough clinical treatment approaches. Body weight changes were recorded during rearing. Antinuclear antibodies (ANA), anti-dsDNA, and anti-snRNP were detected in the mouse serum using an enzyme-linked immunosorbent assay. Apoptosis of Th1 and Th2 immune cells in mice was detected using flow cytometry. Reverse transcription polymerase chain reaction was used to detect the expression of T-bet, GATA3, and Wnt3a mRNA in the spleens of each group. Western blot analysis was performed to detect the expression of Wnt1, p-β-catenin, β-catenin, glycogen synthase kinsase3β (GSK-3β), Wnt3a, c-myc, and cyclin D1 protein in mice spleens. β-catenin in mice spleen was visualized using immunohistochemistry. VitD did not substantial reduce the body weight of MRL/LPR mice, whereas the inhibitor did. VitD notably decreased the concentrations of ANA, anti-double-stranded DNA, and anti-snRNP in the serum of MRL/LPR mice and alleviated apoptosis of Th1 and Th2 cells. VitD markedly increased the expression of T-bet and GATA mRNA in the spleen of MRL/LPR mice and consequently increased the levels of Wnt3a and β-catenin. Western blot analysis revealed that the levels of GSK-3β, p-β-catenin, Wnt1, Wnt3a, c-myc, and cyclin D1 could be reduced by VitD, compared with MRL/LPR. Immunohistochemistry demonstrated that the expression of β-catenin was the most pronounced in the spleen of MRL/LPR mice, and the expression level of β-catenin decreased substantially after VitD intervention. VitD can further inhibit the nuclear translocation of β-catenin by downregulating the expression of Wnt ligands (Wnt1 and Wnt3a), which reduces the expression of the downstream target gene cyclin D1. Systemic lupus erythematosus in mice was improved by inhibiting the activation of Wnt/β-catenin signal pathway.

Thymoquinone improves experimental autoimmune encephalomyelitis by regulating both pro-inflammatory and anti-inflammatory cytokines.

Introduction Multiple sclerosis (MS) is an autoimmune condition marked by inflammation and the loss of myelin in the central nervous system (CNS). The aim of this research was to understand how Thymoquinone regulate the molecular and cellular processes involved in controlling experimental autoimmune encephalomyelitis (EAE), which is an animal model often used to study MS. MethodsFemale C57BL/6 mice were split into different groups receiving different doses (low, medium, and high) of Thymoquinone simultaneously with EAE induction. Clinical scores and other measurements were observed daily throughout the 25-day post immunization. We assessed lymphocyte infiltration and demyelination in the spinal cord through histological staining, analyzed T-cell profiles using ELISA, and quantified the expression levels of transcription factors in the CNS using Real-time PCR. Results Thymoquinone prevented the development of EAE. Histological experiments revealed only a small degree of leukocyte infiltration into the CNS. Thymoquinone resulted in a notable reduction in the generation of IFN-γ, IL-17, and IL-6, while simultaneously increasing the production of IL-4, IL-10, and TGF-β in Th2 and Treg cells. Results from Real-time PCR suggested Treatment with Thymoquinone decreased the expression of T-bet and ROR-γt while increasing the expression of Foxp3 and GATA3. Conclusion These findings showed that Thymoquinone could decrease both disease incidence and severity.

Abstract A059: Heterogeneous cell populations in organoid models derived from breast preinvasive and invasive carcinomas after endocrine therapy

Abstract Approximately 80% of ductal carcinoma in situ (DCIS) and invasive breast cancers express hormone receptors (HR), and are typically treated with selective estrogen receptor modulators (SERMs) or aromatase inhibitors, or with additional HR-targeting agents in the research setting. However, the development of resistance poses a significant challenge. To better understand the mechanisms behind endocrine resistance and explore new treatment strategies, it is essential to have a reliable model system that accurately reflects the heterogeneous nature of breast lesions. In this study, we developed a protocol to generate patient-derived organoid cultures of pre-invasive and malignant breast lesions from patients with persistent or residual disease in the active surveillance or neoadjuvant setting after treatment with endocrine therapy. We generated n = 11 HR+ DCIS and n = 18 HR+ breast cancer organoids and used single-cell RNA-sequencing to characterize cell heterogeneity within individual organoid cultures. We observed mixed non-cancerous and malignant cells present within some cultures, and optimized protocols to minimize non-cancerous cell types. To better define endocrine sensitivity versus resistance, we also assessed responsiveness to estrogen and anti-estrogen therapy in individual cultures by monitoring organoid growth through live cell imaging and evaluating estrogen-response markers at the protein and RNA levels in response to treatment in vitro. Next, we applied our model system to evaluate endocrine resistance in heterogeneous tumor populations. We compared changes in cellular composition and signaling pathways in endocrine-resistant and endocrine-sensitive breast organoids based on in vitro metrics and/or correlation with clinical variables. In addition, within single cultures heterogeneous cell populations were identified with differential expression of ESR1 and HR target genes, generally falling into three cluster groups that could be defined based on different patterns of FOXA1, GATA3, TFF1, and XBP1 expression, among others. These populations also differed with evidence of co-expressed genes and signaling pathways related to breast tumorigenesis and differentiation (estrogen response, androgen response, mTOR signaling, metabolism) in putative HR-active cell populations in both pre-invasive and invasive breast cases. In summary, our study demonstrates that patient-derived breast and breast cancer organoids can be used to model estrogen responsiveness and endocrine resistance. We have established a platform that enables us to investigate the mechanisms underlying endocrine resistance at different premalignant and tumor stages to evaluate new treatment approaches. The ultimate goal of this work is to contribute to the development of new targeted therapies for endocrine-resistant breast lesions. Citation Format: Nadine Goldhammer, Shruti Warhadpande, Liana Beld, Cristian K. Maldonado Rodas, Allison Lam, Tam Binh Bui, Shoko Emily Abe, Michael Alvarado, Cheryl Ewing, Karen Goodwin, Rita Mukhtar, Jasmine Wong, Lamorna Brown Swigart, Gillian Hirst, Christopher Schwartz, Laura van't Veer, Laura Esserman, Jo Chien, Jennifer M. Rosenbluth. Heterogeneous cell populations in organoid models derived from breast preinvasive and invasive carcinomas after endocrine therapy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr A059.

GATA6 Suppresses Lung Adenocarcinoma Progression by Activating CFTR to Modulate Arachidonic Acid Metabolism.

CFTR, which belongs to the ATP-binding cassette transporter family and whose members are always involved in cancer progression, is implicated in lung adenocarcinoma (LUAD) progression, but the underlying mechanism remains undefined. Therefore, this study intended to investigate how CFTR works exactly on LUAD progression. Bioinformatics methods were utilized to analyze GATA6 and CFTR expression in LUAD and targeting relationship, followed by a pathway enrichment analysis of CFTR. GATA6 and CFTR expression levels were assessed by qRT-PCR. Cell viability and proliferation were detected through MTT and colony formation assays. An arachidonic acid (AA) assay kit was utilized to measure AA content. mRNA and protein expression levels of genes (cPLA2, COX-2, and CYP1A1) related to the AA metabolism pathway were detected by qRT-PCR and western blot, respectively. Moreover, the Dual-luciferase reporter gene assay and ChIP were used to verify the binding of GATA6 and CFTR promoters. GATA6 and CFTR were lowly expressed in LUAD, and CFTR was enriched in the AA metabolism pathway. GATA6 activated CFTR transcription. Cellular and rescue experiments revealed that low or high CFTR expression could foster or hamper LUAD cell viability and proliferation, and concomitant treatment of indomethacin, an AA metabolism pathway inhibitor, mitigated stimulation on LUAD progression by low CFTR expression. Silencing of GATA6 reversed the suppressive impact of CFTR overexpression on LUAD progression via modulation of the AA metabolism pathway. The activation of CFTR by GATA6 hampered LUAD progression by modulating the AA metabolism pathway, suggesting that GATA6/CFTR axis might be a therapeutic target for LUAD patients.

A novel GATA3 frameshift mutation causes hypoparathyroidism, sensorineural deafness, and renal dysplasia syndrome

BackgroundHypoparathyroidism, sensorineural deafness, and renal dysplasia (HDR) syndrome (Barakat syndrome) is a rare autosomal dominant disorder caused by mutations in the gene encoding GATA3 on chromosome 10p14. MethodInformed consent was obtained from a 38-year-old female patient. 5 mL of venous blood was collected and sent for whole-exome sequencing. GATA3 constructs of both wild-type and mutant were transfected into HEK-293 T cells. Three-dimensional modeling, luciferase-reporter gene test, western blotting and cellular immunofluorescence were used to evaluate the effect of the mutation. ResultsA novel frameshift mutation c. 677dup(p.Pro227AlafsTer77), named P227Afs, was found in GATA3. Three-dimensional modeling revealed that the mutation caused the loss of the dual zinc finger structures 1 and 2 (ZNF1 and ZNF2) of the synthesized protein. Expression of wild-type GATA3 produced a six-fold increase in luciferase activity when compared with pcDNA3.1 vector only (P < 0.001), whereas the P227Afs mutant showed no increase. The mutation significantly reduced the transcriptional activity of GATA3. Immunofluorescence and western blotting analyses demonstrated that the mutation changed the nuclear location of GATA3 and caused difficulty in nuclearization. ConclusionA novel heterozygous frameshift mutation in GATA3 was identified and showed to result in difficult nuclearization, and a dominant-negative effect on the wild-type.

Single-cell RNA-seq mapping of chicken peripheral blood leukocytes

BackgroundSingle-cell transcriptomics provides means to study cell populations at the level of individual cells. In leukocyte biology this approach could potentially aid the identification of subpopulations and functions without the need to develop species-specific reagents. The present study aimed to evaluate single-cell RNA-seq as a tool for identification of chicken peripheral blood leukocytes. For this purpose, purified and thrombocyte depleted leukocytes from 4 clinically healthy hens were subjected to single-cell 3′ RNA-seq. Bioinformatic analysis of data comprised unsupervised clustering of the cells, and annotation of clusters based on expression profiles. Immunofluorescence phenotyping of the cell preparations used was also performed.ResultsComputational analysis identified 31 initial cell clusters and based on expression of defined marker genes 28 cluster were identified as comprising mainly B-cells, T-cells, monocytes, thrombocytes and red blood cells. Of the remaining clusters, two were putatively identified as basophils and eosinophils, and one as proliferating cells of mixed origin. In depth analysis on gene expression profiles within and between the initial cell clusters allowed further identification of cell identity and possible functions for some of them. For example, analysis of the group of monocyte clusters revealed subclusters comprising heterophils, as well as putative monocyte subtypes. Also, novel aspects of TCRγ/δ + T-cell subpopulations could be inferred such as evidence of at least two subtypes based on e.g., different expression of transcription factors MAF, SOX13 and GATA3. Moreover, a novel subpopulation of chicken peripheral B-cells with high SOX5 expression was identified. An overall good correlation between mRNA and cell surface phenotypic cell identification was shown.ConclusionsTaken together, we were able to identify and infer functional aspects of both previously well known as well as novel chicken leukocyte populations although some cell types. e.g., T-cell subtypes, proved more challenging to decipher. Although this methodology to some extent is limited by incomplete annotation of the chicken genome, it definitively has benefits in chicken immunology by expanding the options to distinguish identity and functions of immune cells also without access to species specific reagents.

Growth hormone directly stimulates GATA2 expression

ObjectiveGATA2 is a key transcription factor involved in the differentiation and determination of thyrotrophs and gonadotrophs in pituitary and hematopoietic development. However, studies on the upstream ligands of the GATA2 signal transduction pathway have been limited. To identify upstream ligands, we examined growth hormone (GH) as a plausible stimulator. DesignWe evaluated GH-induced GATA2 expression in murine TtT/GF thyrotrophic pituitary tumor cells and its direct impact on the GHR/JAK/STAT5 pathway using a combination of a reporter assay, real-time quantitative polymerase chain reaction, and western blotting. ResultsGATA2 expression increased with activated STAT5B in a dose-dependent manner and was inhibited by a STAT5 specific inhibitor. Moreover, we found functional STAT5B binding site consensus sequences at −359 bp in the GATA2 promoter region. ConclusionThese findings suggest that GH directly stimulates GATA2 via the GHR/JAK/STAT pathway and participates in various developmental phenomena mediated by GATA2.