Journal: Frontiers in Oncology

Article Title: Valproate reactivates HTLV-1 tax and reduces ABCB1/MDR1 expression in PBMCs derived from ATLL patients

doi: 10.3389/fonc.2026.1721313

Figure Lengend Snippet: Analysis of efflux pump expression from the ATP-ABC transporter family in PBMCs from HTLV-1-infected patients. (A–E) Expression of five ATP-binding cassette (ABC) transporter genes (ABCA3, ABCB1, ABCB5, ABCC1, and ABCG2) was measured in CD4 + T cells from five non-infected donors (NI), twelve HTLV-1 asymptomatic carriers (AC), and thirteen untreated acute ATLL patients (ATL) by RT-qPCR. Statistical significance was determined using a one-way ANOVA test with Dunn’s multiple comparisons post-test; ns p ≤ 0.05, ** p ≤ 0.01; *** p ≤ 0.001, **** p ≤ 0.0001.

Article Snippet: After two washes in FACS buffer (2000 rpm for 3 minutes), cells were incubated for 2 hours at 4 °C with rabbit monoclonal anti-ABCB1 primary antibody (Cell Signaling, 12683) diluted 1:1000 in FACS buffer.

Techniques: Expressing, Infection, Binding Assay, Quantitative RT-PCR

Journal: Frontiers in Oncology

Article Title: Valproate reactivates HTLV-1 tax and reduces ABCB1/MDR1 expression in PBMCs derived from ATLL patients

doi: 10.3389/fonc.2026.1721313

Figure Lengend Snippet: Verapamil does not inhibit ABCB1 in ATLL primary cells. (A) Western blot of unboiled extracts from control T-cell lines HuT78 (lane 1) and Jurkat (lane 2), and HTLV-1-infected lines HUT-102 (lane 3), C8166 (lane 4), ATL-2 (lane 5). IB, immunoblot. (B) Western blot of unboiled extracts from peripheral blood mononuclear cells of four HTLV-1 asymptomatic carriers (AC; lanes 1–4) and four untreated acute ATLL patients (ATL; lanes 5–8). IB, immunoblot. (C) Densitometric quantification of ABCB1 normalized to actin using ImageJ. Data are mean ± SD; significance by unpaired t-test (p = 0.0026). (D) Calcein-AM efflux assay schematic for measuring ABCB1 activity (D) in T-cell lines (E) and HTLV-1-infected PBMCs (F) . Inhibition is expressed relative to verapamil-treated controls. Data are mean ± SD; one-way ANOVA with Dunn’s multiple-comparisons post-test: ns, not significant; *p ≤ 0.05; **p ≤ 0.01; ***p ≤ 0.001; ****p ≤ 0.0001.

Article Snippet: After two washes in FACS buffer (2000 rpm for 3 minutes), cells were incubated for 2 hours at 4 °C with rabbit monoclonal anti-ABCB1 primary antibody (Cell Signaling, 12683) diluted 1:1000 in FACS buffer.

Techniques: Western Blot, Control, Infection, Activity Assay, Inhibition

Journal: Frontiers in Oncology

Article Title: Valproate reactivates HTLV-1 tax and reduces ABCB1/MDR1 expression in PBMCs derived from ATLL patients

doi: 10.3389/fonc.2026.1721313

Figure Lengend Snippet: Tax inhibits ABCB1 transcription in HEK293T cells. (A) Schematic of transcription-factor binding sites in the proximal ABCB1 promoter. (B) Western blots confirming expression of P65-Flag, P52, SP1, Tax-Flag and JunD-Flag in the presence of HBZ-Myc or Fra-2-HA. Actine served as a loading control. (C) HEK293T cells were co-transfected with a firefly luciferase reporter under the control of an NF-κB–dependent promoter, together with expression vectors for P65-Flag and Tax-Flag. pRcActin-LacZ was included to normalize transfection efficiency. Luciferase activity was measured 48 h post-transfection and is shown as fold change relative to the mock control (set = 1), with mean ± SD from five independent experiments. (D) HEK293T cells were co-transfected with a firefly luciferase reporter driven by the ABCB1 promoter, together with expression vectors for P65-Flag, P52, SP1, Tax-Flag, JunD-Flag, and either HBZ-Myc or Fra-2-HA. pRcActin-LacZ was included to normalize transfection efficiency. Luciferase activity was measured 48 h post-transfection and is shown as fold change relative to the mock control (set = 1), with mean ± SD from seven independent experiments.

Article Snippet: After two washes in FACS buffer (2000 rpm for 3 minutes), cells were incubated for 2 hours at 4 °C with rabbit monoclonal anti-ABCB1 primary antibody (Cell Signaling, 12683) diluted 1:1000 in FACS buffer.

Techniques: Binding Assay, Western Blot, Expressing, Control, Transfection, Luciferase, Activity Assay

Journal: Frontiers in Oncology

Article Title: Valproate reactivates HTLV-1 tax and reduces ABCB1/MDR1 expression in PBMCs derived from ATLL patients

doi: 10.3389/fonc.2026.1721313

Figure Lengend Snippet: Tax inhibits ABCB1 expression in HuT78 and JPx9T-cell lines. (A) HuT78 cells were transfected with P65-Flag, P52, SP1, or Tax-Flag plasmids. Cells were harvested 48 hours post-transfection, and ABCB1 mRNA levels were measured by RT-qPCR. Statistical significance was determined by one-way ANOVA with Dunn’s multiple comparisons post-test (ns, p ≤ 0.05, * p ≤ 0.01, ** p ≤ 0.001, *** p ≤ 0.00001). (B) Western blot analysis of Tax-Flag and ABCB1 expression, with actin as the loading control. (C) Calcein-AM efflux kinetics measuring ABCB1 activity in Hut78 cells for 8 minutes with 100 µM verapamil (green curve) as a control. (D-F) JPX9 cells (human T-cell line with inducible HTLV-1 provirus) were treated for 24 hours with 20 µM cadmium chloride (CdCl2).Tax and ABCB1 expression was measured by RT-qPCR (D) and Western blotting (E, F) Inhibition of ABCB1 efflux activity was measured using the Calcein AM assay. The percentage of inhibition was calculated relative to control cells treated with verapamil.

Article Snippet: After two washes in FACS buffer (2000 rpm for 3 minutes), cells were incubated for 2 hours at 4 °C with rabbit monoclonal anti-ABCB1 primary antibody (Cell Signaling, 12683) diluted 1:1000 in FACS buffer.

Techniques: Expressing, Transfection, Quantitative RT-PCR, Western Blot, Control, Activity Assay, Inhibition, Calcein AM Assay

Journal: Frontiers in Oncology

Article Title: Valproate reactivates HTLV-1 tax and reduces ABCB1/MDR1 expression in PBMCs derived from ATLL patients

doi: 10.3389/fonc.2026.1721313

Figure Lengend Snippet: Tax inhibits ABCB1 expression through its NF-κB signaling. (A) Western blot analyses assessed the expression of P65-Flag, Tax-Flag, Tax M22, and Tax M47, with Actin shown as a loading control. (B) HEK293T cells were co-transfected with a plasmid carrying the firefly luciferase reporter gene under the control of the promoter of ABCB1, along with P65-Flag, Tax-WT Flag, and the Tax mutants Tax M22 (NF-κB deficient) and Tax M47 (CREB deficient) expression vectors, in addition to pRcActin-LacZ for normalization of transfection efficiency. Cells were harvested 48 h post-transfection and assayed for luciferase activity. The results show a fold increase over the mock control and represent the mean values from four independent experiments. (C) Calcein fluorescence accumulation was measured for 8 minutes in HEK293T cells transfected with Tax WT or Tax M22. The percentage of inhibition was assessed relative to that of verapamil-treated untransfected cells.

Article Snippet: After two washes in FACS buffer (2000 rpm for 3 minutes), cells were incubated for 2 hours at 4 °C with rabbit monoclonal anti-ABCB1 primary antibody (Cell Signaling, 12683) diluted 1:1000 in FACS buffer.

Techniques: Expressing, Western Blot, Control, Transfection, Plasmid Preparation, Luciferase, Activity Assay, Fluorescence, Inhibition

Journal: Frontiers in Oncology

Article Title: Valproate reactivates HTLV-1 tax and reduces ABCB1/MDR1 expression in PBMCs derived from ATLL patients

doi: 10.3389/fonc.2026.1721313

Figure Lengend Snippet: Valproic acid enhances the effects of doxorubicin and etoposide in CD8-depleted PBMCs from patients with acute ATL by reducing ABCB1 expression. (A) CD8 + -depleted PBMCs from twelve acute ATLL patients were treated with 5 mM VPA for 5 days, and Tax mRNA levels were measured by RT-qPCR. (B) p19 Gag production after VPA treatment was assessed by ELISA in the supernatant of CD8-depleted PBMCs from five acute ATLL patients at 96 hours post-treatment (error bars indicate standard deviation). (C) ABCB1 mRNA levels post-VPA treatment were determined by quantitative RT-PCR and normalized to HPRT RNA levels. (D) ABCB1 and Tax protein levels in VPA-treated CD8-depleted PBMCs from four ATLL patients were analyzed by Western blot, with actin as a loading control. (E, F) VPA reduces proliferation in ATLL leukemic cells. A CFSE-based proliferation assay was performed on CD8+ depleted PBMCs from four ATLL patients. CFSE was added on day 0, and cells were harvested on day 5. Live lymphocytes were gated using FSC/SSC and FSC/PI (upper panel), and proliferation was modeled with ModFit software (lower panel). A representative example (ATL patient number #7) is shown, comparing cells cultured without VPA (E) or with 5 mM VPA (F, G) CD8+ cell–depleted PBMCs from three patients with acute ATLL were incubated with 5 mM VPA for 24 hours, followed by 48 hours of treatment with increasing concentrations of etoposide or doxorubicin. Cell viability was assessed using PrestoBlue vital dye (Invitrogen), and survival rates were calculated relative to untreated controls.

Article Snippet: After two washes in FACS buffer (2000 rpm for 3 minutes), cells were incubated for 2 hours at 4 °C with rabbit monoclonal anti-ABCB1 primary antibody (Cell Signaling, 12683) diluted 1:1000 in FACS buffer.

Techniques: Expressing, Quantitative RT-PCR, Enzyme-linked Immunosorbent Assay, Standard Deviation, Western Blot, Control, Proliferation Assay, Software, Cell Culture, Incubation

Journal: Biochemistry and Biophysics Reports

Article Title: TMEM207-mediated the impairment of skin regeneration through YAP sequestration in an allergic contact dermatitis model

doi: 10.1016/j.bbrep.2025.102409

Figure Lengend Snippet: (A): (left) Representative immunohistochemical staining of the skin using an anti -ABCB1 antibody. (center) Comparison of PPARg and SCD1 gene expression. (right) Representative immunohistochemical staining of the skin using an anti -SCD1 antibody. ∗∗ no significant difference; ∗P < 0.05. (B): Representative immunohistochemical staining of the skin using an anti -ki67 antibody and Nuclear Ki67 IHC score. Expression of ki67 was significantly reduced in Tg compared to wild type. ∗P < 0.05. (C): Representative immunohistochemical staining of the skin using an anti -Loricrin antibody. (D): Representative immunohistochemical staining of the skin using an anti-YAP antibody.

Article Snippet: Rabbit anti -GAPDH antibodies were obtained from Sigma-Aldrich (St. Louis, MO, USA), and rabbit anti -ABCB1, anti -SCD1, anti -NEDD4, anti -Ki67, anti -Loricrin, and anti-YAP antibodies were purchased from ProteinTech (Proteintech, Inc., USA).

Techniques: Immunohistochemical staining, Staining, Comparison, Gene Expression, Expressing