Journal: Cell Death Discovery

Article Title: Hypoxia promotes progression of cervical cancer by modulating the ATXN3-enhanced P53 stability or STAT5 phosphorylation

doi: 10.1038/s41420-025-02822-0

Figure Lengend Snippet: A IHC detection of HIF1-α, ATXN3, P53, and p-STAT5 proteins in HPV16 + cervical SCC tissues. ( n = 17 HPV16 + SCCs). B Statistical analysis of protein levels in HPV16 + cervical SCC tissues by IHC. ( n = 17 HPV16 + SCCs). C Correlation analysis of protein levels in HPV16 + cervical SCC tissues by IHC. (n = 17 HPV16 + SCCs). D IHC detection of HIF1-α, ATXN3, P53, and p-STAT5 proteins in HPV18 + cervical AC tissues. ( n = 2 HPV18 + ACs). E Statistical analysis of protein levels in HPV18 + cervical AC tissues by IHC. ( n = 2 HPV18 + ACs). F WB assay detecting the protein levels of HIF1-α, ATXN3, P53, and p-STAT5 in HPV16 + cervical SCC tissues and adjacent normal tissues. ( n = 21 HPV16 + SCCs). G Statistical analysis of ATXN3, P53, and p-STAT5 protein levels in HPV16 + cervical SCC tissues and adjacent normal tissues by WB. ( n = 21 HPV16 + SCCs). H Correlation analysis of protein levels in HPV16 + cervical SCC tissues and adjacent normal tissues by WB. ( n = 21 HPV16 + SCCs) I WB assay detecting the protein levels of HIF1-α, ATXN3, P53, and p-STAT5 in HPV18 + cervical AC tissues and adjacent normal tissues. ( n = 4 HPV18 + ACs). J Statistical analysis of ATXN3, P53, and p-STAT5 protein levels in HPV18 + cervical AC tissues and adjacent normal tissues by WB. ( n = 4 HPV18 + ACs). K Correlation analysis of protein levels in HPV18 + AC tissues and adjacent normal tissues by WB. ( n = 4 HPV18 + ACs) The statistical notations used in the figure are:ns P > 0.05, ** P < 0.01, *** P < 0.001, and **** P < 0.0001. Data are represented as mean ± SD. For comparisons involving the HPV18 + AC group ( n = 2 or 4), the Mann-Whitney U test was used. All other comparisons between two groups were performed using a two-tailed unpaired Student’s t test, while linear regression analysis were performed for panels ( C and H ).

Article Snippet: Primary antibodies targeting HIF-1α (1:1000, 36169S, Cell Signaling Technology), ATXN3 (1:1000, MAB5360, Sigma), p-STAT5 (1:1000, #9314 T, Cell Signaling Technology), STAT5 (1:1000, #25656 T, Cell Signaling Technology), P53 (1:1000, #2527 T, Cell Signaling Technology), and β-actin (1:1000, 66009-1-Ig, Proteintech) were used to specifically bind to the corresponding antigens.

Techniques: MANN-WHITNEY, Two Tailed Test

Journal: Cell Death Discovery

Article Title: Hypoxia promotes progression of cervical cancer by modulating the ATXN3-enhanced P53 stability or STAT5 phosphorylation

doi: 10.1038/s41420-025-02822-0

Figure Lengend Snippet: A Effect of ATXN3 overexpression on P53 and p-STAT5 protein levels in C33A, HeLa, and SiHa cells. (n ≥ 3 independent cell cultures). B Statistical analysis of the effect of ATXN3 overexpression on p-STAT5 protein levels in C33A, HeLa, and SiHa cells. Each individual data point represents an independent cell culture experiment. C Statistical analysis of the effect of ATXN3 overexpression on P53 protein levels in C33A, HeLa, and SiHa cells. Each individual data point represents an independent cell culture experiment. D Effect of ATXN3 knockdown on P53 and p-STAT5 protein levels in C33A, HeLa, and SiHa cells. ( n = 3 independent cell cultures). E Statistical analysis of the effect of ATXN3 knockdown on p-STAT5 protein levels in C33A, HeLa, and SiHa cells. Each individual data point represents an independent cell culture experiment. F Statistical analysis of the effect of ATXN3 knockdown on P53 protein levels in C33A, HeLa, and SiHa cells. Each individual data point represents an independent cell culture experiment. G Changes in ATXN3, P53, and p-STAT5 protein levels in C33A, HeLa, and SiHa cells after ATXN3 overexpression or knockdown under hypoxic conditions. ( n = 3 independent cell cultures). H Statistical analysis of changes in ATXN3, P53, and p-STAT5 protein levels in C33A, HeLa, and SiHa cells after ATXN3 overexpression or knockdown under hypoxic conditions. Each individual data point represents an independent cell culture experiment. The statistical notations used in the figure are:ns P > 0.05, ** P < 0.01, *** P < 0.001, and **** P < 0.0001. Data are represented as mean ± SD. Two-tailed unpaired Student’s t -test was employed for analyses in panels ( B , C , E and F ), while One-way ANOVA were performed for panels ( H ).

Article Snippet: Primary antibodies targeting HIF-1α (1:1000, 36169S, Cell Signaling Technology), ATXN3 (1:1000, MAB5360, Sigma), p-STAT5 (1:1000, #9314 T, Cell Signaling Technology), STAT5 (1:1000, #25656 T, Cell Signaling Technology), P53 (1:1000, #2527 T, Cell Signaling Technology), and β-actin (1:1000, 66009-1-Ig, Proteintech) were used to specifically bind to the corresponding antigens.

Techniques: Over Expression, Cell Culture, Knockdown, Two Tailed Test

Journal: Pharmacological research

Article Title: Ectopic expression of NKG7 enhances CAR-T function and improves the therapeutic efficacy in liquid and solid tumors.

doi: 10.1016/j.phrs.2024.107506

Figure Lengend Snippet: Fig. 4. NKG7 promotes the proliferation of CAR-T cells by enhancing the IL-2 signaling pathway. (A and B) GSEA of DNA replication and cell cycle between B7H3- CAR-TNKG7 and B7H3-CAR-T cells following B7H3 protein stimulation for 6 h. (C) Volcano plot of T cell proliferation-related genes between B7H3-CAR-TNKG7 and B7H3-CAR-T cells. (D) Heatmaps of significant T cell proliferation-related genes. (E and F) IL-2 expression of CAR-T cells was measured by FCM analysis following target cell stimulation for 6 h. (G) Statistics for (E and F). (H) The proliferation of CAR-T cells was detected by a CFSE assay. (I and J) GSEA of the Jak-STAT and PI3K- Akt pathways between B7H3-CAR-TNKG7 and B7H3-CAR-T cells following B7H3 protein stimulation for 6 h. (K) The IL-2 signaling pathway (p-AKT (Ser473), AKT, p- ERK (Thr202/Tyr204), ERK, p-STAT5 (Thr694) and STAT5) in CAR-T cells were explored by WB assays. ***P < 0.001.

Article Snippet: After blocking with 5 % nonfat milk at room temperature for 1 h, the membranes were incubated with primary antibodies against NKG7 (Cat No. 84835, 1:1000, CST), AKT (Cat No. A11016, 1:1000, ABclonal), p-AKT (Ser473) (Cat No. AP0140, 1:1000, ABclonal), ERK (Cat No. 4695, 1:1000, CST), p-ERK (Thr202/Tyr204) (Cat No. 4370, 1:1000, CST), STAT5 (Cat No. 25656, 1:1000, CST), pSTAT5 (Thr694) (Cat No. 4322, 1:1000, CST) and β-actin (Cat No. 66009–1-Ig, 1:5000, Proteintech) overnight at 4◦C.

Techniques: Expressing, Cell Stimulation, CFSE Assay

Journal: International Journal of Molecular Sciences

Article Title: Different Lipid Regulation in Ovarian Cancer: Inhibition of the Immune System

doi: 10.3390/ijms19010273

Figure Lengend Snippet: Normal expression and phosphorylation of the IL-2 receptor and its downstream signaling components. PBLs of healthy individuals or sorted ascites-derived CD4 + CD25 − T cells (5 × 10 5 cells/well) were stimulated with 20,000 αCD3/28 beads/well for three days. Subsequently, samples were stained for flow cytometry analysis. ( A ) Cells were stained for isotype control, CD25, CD122, and CD132. Plots are representative for eight controls and three patients. ( B ) Control ( n = 3) and ascites-derived T cells ( n = 3) were stained for JAK3, STAT5, phospho-STAT5, phosphor-AKT and phosphor-ERK. One representative example is shown.

Article Snippet: The following antibodies were used in this study: CD4-APC (300514, Beckman Coulter, Brea, CA, USA), CD4-FITC (A07750, Beckman Coulter), CD25-PE (555432, BD Biosciences, San Jose, CA, USA), CD122-PE (IM1978, Beckman Coulter), CD132-APC (338608, BioLegend, San Diego, CA, USA), cyclin D (2936P, Cell Signaling, Danvers, MA, USA), cyclin E (551159, Cell Signaling, Danvers, MA, USA), JAK3 (ab45141, Abcam, Cambridge, UK), STAT5 (9363P, Cell Signaling, Danvers, MA, USA), pSTAT5 (9314S, Cell Signaling, Danvers, MA, USA), pAKT (4075S, Cell Signaling, Danvers, MA, USA), and pERK1/2 (4284S, Cell Signaling).

Techniques: Expressing, Phospho-proteomics, Derivative Assay, Staining, Flow Cytometry, Control

Journal: Cell Reports Medicine

Article Title: Dual PD-1/IL-2Rα targeting restores CD8 + T cell fitness via STAT5/CD47 axis in SMARCA4-deficient NSCLC

doi: 10.1016/j.xcrm.2026.102633

Figure Lengend Snippet: Attenuated IL-2/STAT5 signaling and an enhanced exhaustion phenotype in CD8 + T cells within SMARCA4-deficient tumors (A) Schematic of the workflow for transcriptomic profiling of CD8 + T cells. (B) Volcano plot displaying differentially expressed genes in CD8 + T cells from SMARCA4-KD versus WT tumors. (C–E) Pathway enrichment analyses of genes downregulated in CD8 + T cells from SMARCA4-KD tumors, including Gene Ontology (GO) terms, KEGG pathways, and Reactome pathways. (F) The gene set enrichment analysis (GSEA) plot. (G) Correlation matrix (pie chart) showing the association between IL-2 receptor subunits expression and key T cell exhaustion marker genes in tumor-infiltrating CD8 + T cells. (H) Radar plot comparing the normalized expression levels of genes encoding IL-2 receptor subunits and exhaustion markers in CD8 + T cells. (I) Quantification by flow cytometry of the expression frequencies of PD-1, TIGIT, and TIM-3 on tumor-infiltrating CD8 + T cells. (J and K) Representative multiplex immunofluorescence (mIF) images of SMARCA4-WT and -KD tumor sections stained for PanCK (cyan), CD8 (green), GZMB (white), PD-1 (red), TIGIT (orange), and TIM-3 (yellow). Scale bars, 20 μm. Data are represented as mean ± SD (error bars) from biological replicates. Statistical analyses, n.s., no significance. Statistical significance was determined by unpaired Student’s t test or one-way ANOVA where appropriate.

Article Snippet: Stat5 (D2O6Y) Rabbit mAb , Cell Signaling Technology , Cat#94205; RRID: AB_2737403.

Techniques: Expressing, Marker, Flow Cytometry, Multiplex Assay, Immunofluorescence, Staining

Journal: Cell Reports Medicine

Article Title: Dual PD-1/IL-2Rα targeting restores CD8 + T cell fitness via STAT5/CD47 axis in SMARCA4-deficient NSCLC

doi: 10.1016/j.xcrm.2026.102633

Figure Lengend Snippet: SMARCA4 loss in tumor cells attenuates CD8 + T cell function via NF-κB-mediated suppression of ICAM1 (A) Flow cytometry analysis of surface expression of the exhaustion markers PD-1, TIGIT, and TIM-3 on human CD8 + T cells following co-culture. (B and C) Representative flow cytometry plots showing the production of IFN-γ and TNF-α and the surface expression of IL-2Rα (CD25) by CD8 + T cells following co-culture. (D) Quantification of the frequencies of IFN-γ + , TNF-α + , and IL-2Rα + cells among co-cultured CD8 + T cells. (E) Integrated single-nucleus RNA sequencing (snRNA-seq) analysis comparing IL2-STAT5 signaling activity. y axis: IL2-STAT5 signaling score. (F and G) Incoming and outgoing signaling patterns between major cell types in the TME, as inferred from snRNA-seq. (H) Specific cell-cell communication network illustrating the ICAM signaling pathway from tumor cells to CD8 + T cells in patients with SMARCA4-WT NSCLC. (I) Correlation analysis between SMARCA4 and ICAM1 mRNA expression in TCGA cohorts. (J) Immunohistochemistry staining and quantification of ICAM1 protein expression in tumor tissues from SMARCA4-WT ( n = 10) and -deficient ( n = 10) NSCLC patients. (K) Schematic illustrating the proposed link between SMARCA4 deficiency and impaired NF-κB activation. (L) Immunoblot analysis of ICAM1 and p65 protein levels in SMARCA4-WT H2122 cells treated with the NF-κB inhibitor PTDC or vehicle control. (M) ChIP-qPCR analysis showing NF-κB (p65) binding to a specific site within the ICAM1 promoter in SMARCA4-WT H2122 cells ( n = 3). (N) Dual-luciferase reporter assay in SMARCA4-WT H2122 cells ( n = 3). Data are represented as mean ± SD (error bars) from biological replicates. Statistical analyses, n.s., no significance, ∗∗∗ p < 0.001, ∗∗∗∗ p < 0.0001. Statistical significance was determined by unpaired Student’s t test or one-way ANOVA where appropriate.

Article Snippet: Stat5 (D2O6Y) Rabbit mAb , Cell Signaling Technology , Cat#94205; RRID: AB_2737403.

Techniques: Cell Function Assay, Flow Cytometry, Expressing, Co-Culture Assay, Cell Culture, RNA Sequencing, Activity Assay, Immunohistochemistry, Staining, Activation Assay, Western Blot, Control, ChIP-qPCR, Binding Assay, Luciferase, Reporter Assay

Journal: Cell Reports Medicine

Article Title: Dual PD-1/IL-2Rα targeting restores CD8 + T cell fitness via STAT5/CD47 axis in SMARCA4-deficient NSCLC

doi: 10.1016/j.xcrm.2026.102633

Figure Lengend Snippet: STAT5 activation mediates the therapeutic effect of the PD-1/IL-2 bsAb in SMARCA4-deficient NSCLC (A) Representative flow cytometry plots showing the expression of the exhaustion markers PD-1, TIGIT, and TIM-3 on activated human CD8 + T cells. (B) Quantification of the mean fluorescence intensity (MFI) of the exhaustion markers PD-1, TIGIT, and TIM-3 on CD8 + T cells from the experiment in (A) ( n = 3). (C) Representative flow cytometry plots showing the production of IFN-γ and TNF-α by CD8 + T cells under the conditions described in (A). (D) Quantification of the frequencies of IFN-γ + and TNF-α + cells among CD8 + T cells ( n = 3). (E) Schematic of the adoptive T cell transfer experiment ( n = 8/group). (F) Representative in vivo bioluminescence images of mice from the indicated groups at different time points. (G) Tumor growth curves, as measured by bioluminescence, for mice in each treatment group. (H) Kaplan-Meier survival curves of mice from the four treatment groups. (I) Quantification of the frequency of donor-derived CD45.2 + CD8 + T cells among total tumor-infiltrating lymphocytes. (J) Flow analysis of donor-derived CD45.2 + CD8 + T cells expressing PD-1, TIGIT, and TIM-3. (K–M) Frequency of IFN-γ + (K–L) and TNF-α + (M) cells among donor-derived CD45.2 + CD8 + T cells. Data are represented as mean ± SD (error bars) from biological replicates. Statistical analyses, n.s., no significance. Statistical significance was determined by unpaired Student’s t test or one-way ANOVA or two-way ANOVA where appropriate.

Article Snippet: Stat5 (D2O6Y) Rabbit mAb , Cell Signaling Technology , Cat#94205; RRID: AB_2737403.

Techniques: Activation Assay, Flow Cytometry, Expressing, Fluorescence, In Vivo, Derivative Assay

Journal: Cell Reports Medicine

Article Title: Dual PD-1/IL-2Rα targeting restores CD8 + T cell fitness via STAT5/CD47 axis in SMARCA4-deficient NSCLC

doi: 10.1016/j.xcrm.2026.102633

Figure Lengend Snippet: PD-1/IL-2 bsAb protects CD8 + T cells from macrophage phagocytosis via STAT5-mediated upregulation of CD47 (A) Schematic of the Cleavage Under Targets and Tagmentation (CUT&Tag) assays workflow. (B) Distribution of STAT5 binding signals relative to transcription start sites (TSS) in CD8 + T cells treated with or without the PD-1/IL-2 bsAb. (C) Genomic annotation of differentially enriched STAT5 binding peaks in the bsAb-treated group. (D) KEGG pathway enrichment analysis of genes associated with STAT5 binding peaks. (E and F) Strategy and Venn diagram for identifying potential STAT5 downstream genes. (G) ChIP-qPCR analysis of STAT5 binding to the promoter regions of selected candidate genes ( n = 3). (H) Genome browser tracks showing STAT5 binding signals at the CD47 locus in control and PD-1/IL-2 bsAb-treated CD8 + T cells. (I) Schematic of the macrophage phagocytosis assay. (J) Representative confocal microscopy images showing macrophages (red) engulfing CD8 + T cells (green). Scale bars, 20 μm. (K) Flow cytometry quantification of the percentage of macrophages that had phagocytosed CD8 + T cells under the indicated conditions ( n = 3). Data are represented as mean ± SD (error bars) from biological replicates. Statistical analyses, n.s., no significance. Statistical significance was determined by unpaired Student’s t test or one-way ANOVA where appropriate.

Article Snippet: Stat5 (D2O6Y) Rabbit mAb , Cell Signaling Technology , Cat#94205; RRID: AB_2737403.

Techniques: Binding Assay, ChIP-qPCR, Control, Phagocytosis Assay, Confocal Microscopy, Flow Cytometry

Journal: Cell Communication and Signaling : CCS

Article Title: Src family kinases interfere with dimerization of STAT5A through a phosphotyrosine-SH2 domain interaction

doi: 10.1186/s12964-014-0081-7

Figure Lengend Snippet: The SH2 domain of STAT5A is required for efficient binding to Src kinases. (A) Domain structure of fluorescently labeled STAT5A-eYFP. (B) Subcellular localization of STAT5A-eYFP in the absence or presence of Epo. HeLa T-REx HA-EpoR cells stably transfected with STAT5A-eYFP were stimulated with 1 U/ml Epo for 30 min and the localization of STAT5A-eYFP was analyzed by confocal microscopy. Scale bars: 20 μm. (C) Subcellular localization of STAT5A-eYFP (upper panel), STAT5A R618Q -eYFP (middle panel) and STAT3-eYFP (lower panel) was investigated in the presence of vSrc-dsRed. HeLa T-REx vSrc-dsRed cells were treated with 5 ng/ml doxycycline and transfected with the indicated constructs and the distribution of fluorescently labeled fusion proteins was analyzed after 24 h by confocal microscopy. Scale bars: 20 μm. (D) Quantification of the relative subcellular distribution of eYFP-labeled STAT3 and STAT5A constructs in HeLa T-REx HA-EpoR cells stably expressing STAT5A-eYFP (B) and HeLa T-REx vSrc-dsRed cells transfected with STAT5A-eYFP, STAT5A R618Q -eYFP or STAT3-eYFP (C) . The expression of the HA-EpoR and vSrc-dsRed was induced with 5 ng/ml doxycycline for 24 hours. Mean fluorescence intensities (MFI) of the cytoplasm and nucleus were determined using the Zen 2012 software and changes in the ratio between the compartments were plotted. The data shown are means ± SD of n = 30 cells and were statistically evaluated by Student’s t -test. ***p < 0.0005. n.s. = not significant. (E + F) HeLa T-REx FRT cells were co-transfected with plasmids coding for STAT5A-eYFP or STAT5A R618Q -eYFP and vSrc-dsRed or Hck-dsRed. Fluorescently labeled STAT5 was immunoprecipitated from cell lysates using a GFP antibody and analyzed by immunoblotting for the presence of vSrc-dsRed or Hck-dsRed 24 h after transfection. The expression and phosphorylation of STAT5A and vSrc/Hck proteins was analyzed in the whole cellular lysates (WCL) using antibodies against pY 416 -Src, Src, Hck, pY 694/699 -STAT5A/B and GFP.

Article Snippet: Anti-pY 694/699 -STAT5A/B (#9351), anti-pY 416 -Src (#2101), anti-pY 412 -Abl (#2865), anti-Hsp70 (#4872, Cell Signaling, Beverly, USA), anti-STAT5A (clone #5073, rabbit polyclonal antiserum was kindly provided by Richard Moriggl, Ludwig Boltzmann Institute for Cancer Research (LBI-CR), Vienna, Austria), anti-GFP (600-103-215, Rockland, Gilbertsville, USA), anti-FLAG (F3165), anti-α-tubulin (T5168, Sigma, St. Louis, USA), anti-GAPDH (sc-32233), anti-Abl (sc-131), anti-Hck (sc-72), anti-cSrc (sc-19, Santa Cruz Biotechnology, Santa Cruz, USA), anti-vSrc (MABS193, Millipore, Billerica, MA, USA) and anti-HA (MMS-101R, Covance, Princeton, New Jersey, USA) antibodies were used for immunoblotting.

Techniques: Binding Assay, Labeling, Stable Transfection, Transfection, Confocal Microscopy, Construct, Expressing, Fluorescence, Software, Immunoprecipitation, Western Blot

Journal: Cell Communication and Signaling : CCS

Article Title: Src family kinases interfere with dimerization of STAT5A through a phosphotyrosine-SH2 domain interaction

doi: 10.1186/s12964-014-0081-7

Figure Lengend Snippet: STAT5A binds to the phosphorylated activation loop of SFK. (A) Domain structure of vSrc-dsRed. Selected amino acids are highlighted. A multiple sequence alignment of the activation loop of SFK is shown. Autophosphorylation site is highlighted (red). (*) conserved amino acids, (:) similar properties . Bold characters highlight peptide sequence used for precipitation. (B + C) HeLa T-REx FRT cells stably expressing STAT5A-eYFP were transfected with the indicated vSrc-dsRed variants. Phosphorylation was analyzed 24 h after transfection using antibodies against pY 416 -Src, Src, pY 694/699 -STAT5A/B and STAT5A. CTRL = untransfected cells. (D) Quantification of relative subcellular distribution of STAT5A in HeLa T-REx FRT stably expressing STAT5A-eYFP and the indicated vSrc-dsRed mutants. Mean fluorescence intensity (MFI) of eYFP-fluorescence in the cytoplasm and nucleus were determined using the Zen 2012 software and changes in the ratio between the compartments were plotted. Data show means ± SD of n = 10 cells and were statistically evaluated by Student’s t -test. ***p < 0.0005, **p < 0.005, *p < 0.05, n.s. = not significant. (E) HeLa T-REx FRT cells stably expressing STAT5A-eYFP were transfected with vSrc K295N -dsRed or vSrc Y416F -dsRed. Subcellular distribution of STAT5A-eYFP was analyzed 24 h after transfection by confocal microscopy. Scale bars: 20 μm. (F + G) HeLa T-REx FRT cells were co-transfected with plasmids coding for vSrc-dsRed (Hck-dsRed), vSrc K295N -dsRed (Hck K269N -dsRed) or vSrc Y416F -dsRed (Hck Y390F -dsRed) and STAT5A-eYFP. STAT5-eYFP was immunoprecipitated from cell lysates using a GFP antibody and analyzed by immunoblotting for the presence of vSrc-dsRed (Hck-dsRed) 24 h after transfection. Expression and phosphorylation of STAT5A and vSrc proteins was analyzed in the WCL using antibodies against pY 416 -Src, Src, Hck, pY 694/699 -STAT5A/B and GFP. (s) short exposure, (l) long exposure. (H) HeLa T-REx FRT cells expressing STAT5A-eYFP or STAT5A R618Q -eYFP were lysed and incubated with a Src-peptide containing tyrosine- or phosphotyrosine 416. Precipitates and WCL were analyzed by immunoblotting using a GFP-specific antibody.

Article Snippet: Anti-pY 694/699 -STAT5A/B (#9351), anti-pY 416 -Src (#2101), anti-pY 412 -Abl (#2865), anti-Hsp70 (#4872, Cell Signaling, Beverly, USA), anti-STAT5A (clone #5073, rabbit polyclonal antiserum was kindly provided by Richard Moriggl, Ludwig Boltzmann Institute for Cancer Research (LBI-CR), Vienna, Austria), anti-GFP (600-103-215, Rockland, Gilbertsville, USA), anti-FLAG (F3165), anti-α-tubulin (T5168, Sigma, St. Louis, USA), anti-GAPDH (sc-32233), anti-Abl (sc-131), anti-Hck (sc-72), anti-cSrc (sc-19, Santa Cruz Biotechnology, Santa Cruz, USA), anti-vSrc (MABS193, Millipore, Billerica, MA, USA) and anti-HA (MMS-101R, Covance, Princeton, New Jersey, USA) antibodies were used for immunoblotting.

Techniques: Activation Assay, Sequencing, Stable Transfection, Expressing, Transfection, Fluorescence, Software, Confocal Microscopy, Immunoprecipitation, Western Blot, Incubation

Journal: Cell Communication and Signaling : CCS

Article Title: Src family kinases interfere with dimerization of STAT5A through a phosphotyrosine-SH2 domain interaction

doi: 10.1186/s12964-014-0081-7

Figure Lengend Snippet: SFK-mediated cytoplasmic localization of STAT5A is dominant over BCR-ABL induced nuclear accumulation. (A) HeLa T-REx BCR-ABL cells were transiently transfected with STAT5A-eYFP and either treated with 5 ng/ml doxycycline for 24 h to induce BCR-ABL expression (lower panel) or left untreated (upper panel). Fixation was performed with methanol. Fixed cells were stained for BCR-ABL using a cABL-specific primary antibody and a secondary antibody conjugated to Alexa Fluor-405. The subcellular distribution of STAT5A-eYFP was analyzed by confocal microscopy. Scale bars: 20 μm. (B) The subcellular distribution of STAT5A-eYFP was investigated in the presence of vSrc-dsRed (upper panel), vSrc K295N -dsRed (middle panel) or vSrc Y416F -dsRed (lower panel) in HeLa T-REx BCR-ABL cells that were treated with 5 ng/ml doxycycline for 24 h. Fixation was performed with methanol. Fixed cells were stained for BCR-ABL using an Abl-specific primary antibody and a secondary antibody conjugated to Alexa Fluor-405. Scale bars: 20 μm. (C) HeLa T-REx BCR-ABL cells were co-transfected with vSrc-dsRed, or the respective kinase activity affecting mutants vSrc K295N -dsRed or vSrc Y416F -dsRed and STAT5A-eYFP. The cells were either treated with 5 ng/ml doxycycline for 24 h (lanes 1–3) to induce the expression of BCR-ABL or left untreated (lane 4). Protein expression and phosphorylation in the cellular extracts was investigated by immunoblotting with antibodies against pY 412 -cABL, cABL, pY 694/699 -STAT5A/B, STAT5A, pY 416 -Src and Src. α-Tubulin served as a loading control.

Article Snippet: Anti-pY 694/699 -STAT5A/B (#9351), anti-pY 416 -Src (#2101), anti-pY 412 -Abl (#2865), anti-Hsp70 (#4872, Cell Signaling, Beverly, USA), anti-STAT5A (clone #5073, rabbit polyclonal antiserum was kindly provided by Richard Moriggl, Ludwig Boltzmann Institute for Cancer Research (LBI-CR), Vienna, Austria), anti-GFP (600-103-215, Rockland, Gilbertsville, USA), anti-FLAG (F3165), anti-α-tubulin (T5168, Sigma, St. Louis, USA), anti-GAPDH (sc-32233), anti-Abl (sc-131), anti-Hck (sc-72), anti-cSrc (sc-19, Santa Cruz Biotechnology, Santa Cruz, USA), anti-vSrc (MABS193, Millipore, Billerica, MA, USA) and anti-HA (MMS-101R, Covance, Princeton, New Jersey, USA) antibodies were used for immunoblotting.

Techniques: Transfection, Expressing, Staining, Confocal Microscopy, Activity Assay, Western Blot

Journal: Cell Communication and Signaling : CCS

Article Title: Src family kinases interfere with dimerization of STAT5A through a phosphotyrosine-SH2 domain interaction

doi: 10.1186/s12964-014-0081-7

Figure Lengend Snippet: Binding of STAT5A to Src kinases interferes with dimerization. (A) HeLa T-REx HA-EpoR cells stably expressing STAT5A-eYFP were transfected with STAT5A-FLAG. The cells were treated with 5 ng/ml doxyxcyline for 24 h to induce the expression of the HA-tagged EpoR and stimulated with 5 U/ml Epo for 30 minutes or left untreated. HeLa T-REx vSrc-dsRed cells stably expressing STAT5A-eYFP were transfected with STAT5A-FLAG. The expression of vSrc-dsRed was induced for 8 h with 5 ng/ml doxycycline or the cells were left untreated. STAT5A-eYFP was immunoprecipitated from cell lysates using a GFP antibody and analyzed by immunoblotting for the presence of STAT5A-FLAG. The expression and phosphorylation of STAT5A-eYFP and STAT5A-FLAG was analyzed in the WCL using antibodies against pY 694/699 -STAT5A/B, GFP and the FLAG-tag. (B) HeLa T-REx HA-EpoR cells stably expressing STAT5A-eYFP were treated with 5 ng/ml doxyxcyline for 24 h to induce the expression of the human EpoR and stimulated with 5 U/ml Epo for 30 minutes or left untreated. HeLa T-REx vSrc-dsRed cells stably expressing STAT5A-eYFP or a STAT5A S710F -eYFP were treated with 5 ng/ml doxyxcline for 8 h or the cells were left untreated. Cellular extracts were prepared under native conditions and STAT5A-eYFP dimers were separated from monomers by blue native PAGE electrophoresis (NP). STAT5A-eYFP dimer complexes were measured by the detection of the eYFP fluorescence. The cellular extracts were subjected to immunoblotting using antibodies against pY 694/699 -STAT5A/B, STAT5A, Src and the HA-tag of the EpoR. (C) Confocal microscopy analysis of HeLa T-REx FRT cells co-expressing vSrc-dsRed together with STAT5A S710F -eYFP (upper panel), a serine phosphorylation mimicking mutant STAT5A S710D -eYFP (middle panel) or a serine phosphorylation deficient mutant STAT5A S710A -eYFP (lower panel). Methanol fixation was performed 24 h after transfection. Scale bars: 20 μm.

Article Snippet: Anti-pY 694/699 -STAT5A/B (#9351), anti-pY 416 -Src (#2101), anti-pY 412 -Abl (#2865), anti-Hsp70 (#4872, Cell Signaling, Beverly, USA), anti-STAT5A (clone #5073, rabbit polyclonal antiserum was kindly provided by Richard Moriggl, Ludwig Boltzmann Institute for Cancer Research (LBI-CR), Vienna, Austria), anti-GFP (600-103-215, Rockland, Gilbertsville, USA), anti-FLAG (F3165), anti-α-tubulin (T5168, Sigma, St. Louis, USA), anti-GAPDH (sc-32233), anti-Abl (sc-131), anti-Hck (sc-72), anti-cSrc (sc-19, Santa Cruz Biotechnology, Santa Cruz, USA), anti-vSrc (MABS193, Millipore, Billerica, MA, USA) and anti-HA (MMS-101R, Covance, Princeton, New Jersey, USA) antibodies were used for immunoblotting.

Techniques: Binding Assay, Stable Transfection, Expressing, Transfection, Immunoprecipitation, Western Blot, FLAG-tag, Blue Native PAGE, Electrophoresis, Fluorescence, Confocal Microscopy, Mutagenesis

Journal: Cell Communication and Signaling : CCS

Article Title: Src family kinases interfere with dimerization of STAT5A through a phosphotyrosine-SH2 domain interaction

doi: 10.1186/s12964-014-0081-7

Figure Lengend Snippet: Activated SFK interfere with dimerization and nuclear translocation of pSTAT5A in BCR-ABL expressing cells. Left scheme: Classical activation of the JAK2-STAT5A signaling pathway downstream of the EpoR. Right scheme: BCR-ABL directly phosphorylates STAT5A Y694 resulting in STAT5A dimerization, nuclear accumulation and finally target gene expression . In the presence of BCR-ABL, a predominantly cytoplasmic localization of pSTAT5A is achieved (i) upon binding to the scaffolding adaptor Gab2 resulting in pro-survival signaling through PI3K/Akt activation and (ii) through binding of the STAT5A SH2 domain to the phosphorylated activation loop of SFK, a mechanism that interferes with STAT5A dimerization and subsequent nuclear accumulation. Constitutively active STAT5A S710F escapes the SFK-mediated cytoplasmic retention. Flashes indicate phosphorylation events.

Article Snippet: Anti-pY 694/699 -STAT5A/B (#9351), anti-pY 416 -Src (#2101), anti-pY 412 -Abl (#2865), anti-Hsp70 (#4872, Cell Signaling, Beverly, USA), anti-STAT5A (clone #5073, rabbit polyclonal antiserum was kindly provided by Richard Moriggl, Ludwig Boltzmann Institute for Cancer Research (LBI-CR), Vienna, Austria), anti-GFP (600-103-215, Rockland, Gilbertsville, USA), anti-FLAG (F3165), anti-α-tubulin (T5168, Sigma, St. Louis, USA), anti-GAPDH (sc-32233), anti-Abl (sc-131), anti-Hck (sc-72), anti-cSrc (sc-19, Santa Cruz Biotechnology, Santa Cruz, USA), anti-vSrc (MABS193, Millipore, Billerica, MA, USA) and anti-HA (MMS-101R, Covance, Princeton, New Jersey, USA) antibodies were used for immunoblotting.

Techniques: Translocation Assay, Expressing, Activation Assay, Binding Assay, Scaffolding