Journal: bioRxiv

Article Title: RNA polymerase loss by nuclear rupture drives LMNA cardiomyopathy

doi: 10.64898/2026.04.03.716433

Figure Lengend Snippet: A) Immunofluorescence for gamma-H2AX in cardiomyocytes expressing NLS-tdTomato and GFP-icGAS isolated from mice at day 14 post tamoxifen. Texts and icons below images indicate nuclear states. Scale bar: 5 μm. B) Nuclear gamma-H2AX intensity by nuclear states. Density and box plots (interquartile range): signal distribution of all affiliated nuclei. Circles: mean intensity within individual biological replicates (color coded). Statistics: P < 0.05 (*) or P≥0.05 (N.S.) from t-tests on linear regression-estimated means with mouse-clustered standard errors. Underlying data: 164 intact nuclei from 3 WT mice, 152 intact, 116 ruptured, 50 resealed nuclei from 3 Lmna CKO mice. C) Relationship between gamma-H2AX intensity and NLS-tdTomato intensity in nuclei of Lmna CKO cardiomyocytes (340 nuclei from 3 mice). Line: simple linear regression fit with 95% confidence interval. R: Pearson’s correlation coefficient. P: t-test p -value on linear regression-estimated means with mouse-clustered standard errors.

Article Snippet: Rabbit anti-gamma-H2AX antibody (Cell signaling, 9718); mouse anti-BrU/BrdU antibody (BD Biosciences, 555627); rabbit anti-RNA Pol II N-terminal domain (NTD) antibody (Cell signaling, 14958); rat anti-RNA Pol II CTD phospho-Ser5 antibody (Chromotek, AB_2631404); rat anti-RNA Pol II CTD phospho-Ser2 antibody (Millipore Sigma, 04-1571); mouse anti-Lamin A/C antibody (Santa Cruz, sc-376248); rabbit anti-Lamin A antibody (Abcam, ab26300); rabbit anti-PCM1 antibody (Sigma, HPA023370); mouse anti-BANF1 antibody (Abnova, H00008815-M01); rabbit anti-LEMD2 antibody (Millipore Sigma, HPA017340); rabbit anti-CHMP4B antibody (Proteintech, 13683-1-AP); rabbit anti-CHMP7 antibody (Proteintech, 16424-1-AP); mouse anti-VPS4 antibody (Santa Cruz, sc-133122); and mouse anti-c-Myc antibody (Invitrogen, 13-2500).

Techniques: Immunofluorescence, Expressing, Isolation

Journal: International Journal of Oncology

Article Title: Overcoming acquired doxorubicin resistance of ovarian carcinoma cells by verapamil-mediated promotion of DNA damage-driven cytotoxicity

doi: 10.3892/ijo.2026.5861

Figure Lengend Snippet: Effect of Topo II inhibitors on DNA damage formation and activation of DDR-related mechanisms in A2780 and A2780ADR cells. (A) At 24 h after treatment of logarithmically growing cells with the indicated concentrations of Doxo or Eto, the number of nuclear γH2AX-foci, 53BP1-foci, γH2AX/53BP1 co-localized foci and γH2AX pan-stained cells was analyzed. The upper part of the figure shows representative images (total magnification, ×1,000). Quantitative data depicted in the histogram are the mean ± SD from n=3 independent experiments with each five images being analyzed per experimental condition. * P≤0.05; ** P≤0.01; *** P≤0.001 (A2780 vs. A2780ADR); # P≤0.05; ## P≤0.01; ### P≤0.001 (treated vs. untreated control). Control experiments performed by use of 1st or 2nd antibody only or no antibody at all did not interfere with the signal of main interest (that is, nuclear foci; data not shown). (B) Logarithmically growing cells were treated with the indicated concentrations of Doxo for 24 or 72 h. Afterwards, the protein expression of DDR-related factors was analyzed by western blotting using EKR2 protein expression as loading control. Doxo, doxorubicin; Eto, etoposide; p-, phosphorylated; Chk1/2, checkpoint kinase 1/2; ERK2, extracellular regulated kinase; γH2AX, Ser139 phosphorylated histone H2AX; 2; Kap1, KRAB-associated protein 1; PARP, poly (ADP-ribose) polymerase; p21, cyclin-dependent kinase inhibitor 1; p53, tumor suppressor p53.

Article Snippet: The following primary antibodies were used: Copper transporting ATPase (ATP7A), extracellular regulated kinase 2 (ERK2), phosphorylated (p)-histone H3 (Ser10) from Thermo Fisher Scientific Inc., cleaved caspase-7 (Asp198), p-Chk1 (Ser 345), cyclin B1, galactosidase β (E2U2I), GAPDH (14C10), MDR1/ABCB1 (D3H1Q), p-P53 (S15), PARP, TopBP1(D8G4L), topoisomerase IIa (D10G9), 53BP1 and Ki67 were from Cell Signaling Technology Inc., pChk2 (T68) [Y171], copper uptake protein 1 (CTR1/SLC31A1) [EPR7936] and Rad51 from Abcam, γH2AX (Ser 139) clone JBW301, p-KAP-1 (S824) and p-RPA32 (S4/S8) from Bethyl Laboratories Inc., organic cation transporter-2 (OCT2) from Biozol Diagnostics Vertrieb GmbH, p16 (F-12) and p21 (C-19) from Santa Cruz Biotechnology, Inc. As secondary antibodies, horseradish peroxidase-conjugated secondary antibodies goat anti-mouse IgG and mouse anti-rabbit IgG were used (Rockland Immunochemicals Inc.).

Techniques: Activation Assay, Staining, Control, Expressing, Western Blot

Journal: International Journal of Oncology

Article Title: Overcoming acquired doxorubicin resistance of ovarian carcinoma cells by verapamil-mediated promotion of DNA damage-driven cytotoxicity

doi: 10.3892/ijo.2026.5861

Figure Lengend Snippet: Influence of combined treatment of A2780ADR with Doxo and selected inhibitors on DNA damage formation, proliferation and cell death. (A) At 24 h after treatment of logarithmically growing cells with the indicated concentrations of Doxo and inhibitors (EHT, 5 μ M; EST, 1 μ M; Ver, 50 μ M), the number of nuclear γH2AX-foci, 53BP1-foci, γH2AX/53BP1 co-localized foci and γH2AX pan-stained cells was analyzed as described in methods. The upper part of the figure shows representative images (total magnification, ×1,000). Quantitative data depicted in the histogram are the mean ± SD from n=5 microscopical images analyzed per experimental condition. * P≤0.05, ** P≤0.01, *** P≤0.001 mono-treatment vs. co-treatment; # P≤0.05, ## P≤0.01, ### P≤0.001 untreated vs. treated group). (B) Logarithmically growing Doxo resistant A2780ADR cells were co-treated with the indicated concentrations of Doxo and selected pharmacological inhibitors (EHT, 5 μ M; EST, 1 μ M; Ver, 50 μ M). At 24 h later, cells were pulse-labeled with EdU to monitor proliferation as described in methods and the percentage of EdU positive cells was determined microscopically (total magnification, ×400). Quantitative data shown in the histogram are the mean ± SD from five replicates. ** P≤0.05; ## P≤0.01; ### P≤0.001 (vs. untreated control). (C) PI staining of mono- and co-treated A2780ADR cells 72 h after treatment with Doxo (0.1 μ M) and pharmacological inhibitors (EHT, 5 μ M; EST, 1 μ M; Ver, 50 μ M). Left panel: representative images; right panel: percentage of PI positive cells (mean ± SD from n=5 microscopical images analyzed per experimental condition) (40× microscope objective). * P≤0.05; ** P≤0.01. mono-treatment vs. co-treatment; # P≤0.05; ## P≤0.01, Con vs treated group. Doxo, doxorubicin; EST, entinostat; EHT, Rac1 inhibitor EHT1864; Ver, verapamil; SD, standard deviation; PI, propidium iodide.

Article Snippet: The following primary antibodies were used: Copper transporting ATPase (ATP7A), extracellular regulated kinase 2 (ERK2), phosphorylated (p)-histone H3 (Ser10) from Thermo Fisher Scientific Inc., cleaved caspase-7 (Asp198), p-Chk1 (Ser 345), cyclin B1, galactosidase β (E2U2I), GAPDH (14C10), MDR1/ABCB1 (D3H1Q), p-P53 (S15), PARP, TopBP1(D8G4L), topoisomerase IIa (D10G9), 53BP1 and Ki67 were from Cell Signaling Technology Inc., pChk2 (T68) [Y171], copper uptake protein 1 (CTR1/SLC31A1) [EPR7936] and Rad51 from Abcam, γH2AX (Ser 139) clone JBW301, p-KAP-1 (S824) and p-RPA32 (S4/S8) from Bethyl Laboratories Inc., organic cation transporter-2 (OCT2) from Biozol Diagnostics Vertrieb GmbH, p16 (F-12) and p21 (C-19) from Santa Cruz Biotechnology, Inc. As secondary antibodies, horseradish peroxidase-conjugated secondary antibodies goat anti-mouse IgG and mouse anti-rabbit IgG were used (Rockland Immunochemicals Inc.).

Techniques: Staining, Labeling, Control, Microscopy, Standard Deviation

Journal: International Journal of Oncology

Article Title: Overcoming acquired doxorubicin resistance of ovarian carcinoma cells by verapamil-mediated promotion of DNA damage-driven cytotoxicity

doi: 10.3892/ijo.2026.5861

Figure Lengend Snippet: Influence of combined treatment of A2780ADR cells with Doxo and selected inhibitors on mechanism of the DDR and mRNA expression of selected susceptibility-related genes. (A) Logarithmically growing A2780ADR cells were co-treated with the indicated concentrations of Doxo and selected pharmacological inhibitors (concentrations see ) for 24 or 72 h. Afterwards, the protein expression of DDR-related factors was analyzed by western blotting. For loading control, blots were reprobed with ERK2 antibody. (B) Reverse transcription-quantitative PCR of the mRNA expression of selected factors known to contribute to different mechanisms of drug sensitivity. Data shown are mean ± SD from triplicate determinations as described in methods. Relative mRNA level in untreated A2780ADR cells was set to 1.0. Doxo, doxorubicin; DDR, DNA damage response; p-, phosphorylated; nd, not detectable; Bax, Bcl-2 associated protein X; Bcl-2, B-cell lymphoma; BBC3, Bcl-2 binding component 2; BRCA1, 2, breast cancer associated gene 1,2; Cl casp-7, cleaved caspase 7; Chk, checkpoint kinase; CXCL8, chemokine ligand 8 (interleukin 8); p21, CDK inhibitor 1; p16, CDK inhibitor 2; CDKN1A/2A, cyclin dependent kinae inhibitor 1A/2A; CCNB1, Cyclin B1; b-Gal, beta-galactosidase; FASL, FAS ligand; FASR, FAS receptor; GADD, growth arrest and DNA damage inducible GPX1, glutathione peroxidase 1; GSTM1, glutathione S-transferase 1; HMOX1, heme oxygenase 1; γH2AX, Ser139 phosphorylated histone H2AX; p53, tumor suppressor p53; PARP, poly (ADP-ribose) polymerase; PCNA-proliferating cell nuclear antigen; PGC1A, PPARG coactivator 1; PPARGC1A, peroxisome proliferator-activated receptor gamma coactivator 1-alpha; RAD51, radiation damage gene 51; RPAreplication protein A; SOD1, superoxide dismutase 1; Ver, verapamil.

Article Snippet: The following primary antibodies were used: Copper transporting ATPase (ATP7A), extracellular regulated kinase 2 (ERK2), phosphorylated (p)-histone H3 (Ser10) from Thermo Fisher Scientific Inc., cleaved caspase-7 (Asp198), p-Chk1 (Ser 345), cyclin B1, galactosidase β (E2U2I), GAPDH (14C10), MDR1/ABCB1 (D3H1Q), p-P53 (S15), PARP, TopBP1(D8G4L), topoisomerase IIa (D10G9), 53BP1 and Ki67 were from Cell Signaling Technology Inc., pChk2 (T68) [Y171], copper uptake protein 1 (CTR1/SLC31A1) [EPR7936] and Rad51 from Abcam, γH2AX (Ser 139) clone JBW301, p-KAP-1 (S824) and p-RPA32 (S4/S8) from Bethyl Laboratories Inc., organic cation transporter-2 (OCT2) from Biozol Diagnostics Vertrieb GmbH, p16 (F-12) and p21 (C-19) from Santa Cruz Biotechnology, Inc. As secondary antibodies, horseradish peroxidase-conjugated secondary antibodies goat anti-mouse IgG and mouse anti-rabbit IgG were used (Rockland Immunochemicals Inc.).

Techniques: Expressing, Western Blot, Control, Reverse Transcription, Real-time Polymerase Chain Reaction, Binding Assay