Journal: Cell death discovery

Article Title: Dual role of p21 in regulating apoptosis and mitotic integrity in response to doxorubicin in colon cancer cells.

doi: 10.1038/s41420-025-02416-w

Figure Lengend Snippet: Fig. 5 Impaired DNA damage repair in p21-deficient cells after low-dose doxorubicin treatment. A Western blot analysis of phosphorylated ATM (p-ATM), p-Chk1, Chk1, p-Chk2, and Chk2 in WT, p53−/−, and p21−/−cells treated with 100 nM doxorubicin for various time points. β-actin was used as a loading control. B Fluorescence microscopy of Lamin B1 (red) and γ-H2AX foci (green) in WT, p53−/−, and p21−/−cells treated with 100 nM doxorubicin for 48 h. Scale Bar = 20 μm. C Fluorescence microscopy showing nuclei (blue) and γ-H2AX foci (green) in HCT116 WT, p53−/−, and p21−/−cells treated with 100 nM doxorubicin for 24 h and then released into fresh media for various time points. Scale bar = 20 μm. Quantification of nuclei with >10 γ-H2AX foci (n = 20 cells per group, repeated 4 times). Data are mean ± SD ****p < 0.0001.

Article Snippet: The following antibodies were used: β-actin (sc-69879), p53 (sc-126), Lamin B1(sc-365214), αtubulin (sc-5286), Noxa (sc-515840, and MKLP1 (sc-136473) (Santa Cruz Biotechnologies, Dallas, TX, USA); p21 (ab109520), phospho-ATM (S1981) (ab81292), and phospho-DNA PKcs (S2056) (ab18192)(Abcam, Cambridge, MA, USA); phospho-Chk1 (Ser345)(# 2348), Chk1 (#2360), phospho-Chk2 (Thr68)(# 2197), Chk2 (#6334), cleaved caspase-3 (#9664), phospho-Histone H2A.X (Ser139)(# 9718), Mcl-1 (#39224), and Aurora B (#3094) (Cell signaling technology, Danvers, MA, USA); Mre11(GTX70212) and α-tubulin (GTX112141) (Genetex, San Antonio, Texas, USA); DNA-PKcs (19983-1-AP) (Proteintech, Rosemont, IL, USA); HRP-conjugated rabbit IgG and mouse IgG (Jackson Immunoresearch, West Grove, PA, USA).

Techniques: Western Blot, Control, Fluorescence, Microscopy

Journal: Oncology Letters

Article Title: Poly (ADP-ribose) polymerase-1 inhibition decreases proliferation through G2/M arrest in esophageal squamous cell carcinoma

doi: 10.3892/ol.2017.6334

Figure Lengend Snippet: Inhibition of PARP1-induced cell cycle arrest at the G2/M checkpoint. (A) Cell cycle analysis of TE6 and TE9 cells transfected with siPARP1 (n=3, cells transfected with siPARP1 were compared with the NC for each cell cycle). Compared with NC, siPARP1 significantly increased the ratio of cells in the G2/M phase and significantly decreased the ratio of cells in the G0/G1 phase. (B) Schema of ATM-Chk2-cdc25c pathways and cdc2/cyclin B1. (C) Western blot analysis showed that inhibition of PARP1 induced cell cycle arrest at the G2/M checkpoint through the ATM-Chk2-cdc25c pathway. PARP, poly (ADP-ribose) polymerase-1; siPARP1, small interfering RNA against PARP1; NC, negative control; KD, knock-down; cdc, cell division control; ATM, ataxia telangiectasia mutated; Chk2, checkpoint kinase 2.

Article Snippet: The primary antibodies used for western blot analysis were obtained from Cell Signaling Technology, Inc. (Danvers, MA, USA) and were as follows: Rabbit anti-checkpoint kinase 2 (Chk2) (catalog no. 2662S; dilution, 1:1,000); rabbit anti-phospho-Chk2 (Thr68) (catalog no. 2661S; dilution, 1:1,000); rabbit anti-cell division control (cdc) 25c (catalog no. 4688S; dilution, 1:1,000); rabbit anti-phospho-cdc25c (Thr48) (catalog no. 9527S; dilution, 1:1,000); mouse anti-cdc2 (catalog no. 9116S; dilution, 1:1,000); rabbit anti-phospho-cdc2 (Tyr15) (catalog no. 9111S; dilution, 1:1,000); and rabbit anti-cyclin B1 (catalog no. 4138S; dilution, 1:1,000).

Techniques: Inhibition, Cell Cycle Assay, Transfection, Western Blot, Small Interfering RNA, Negative Control, Knockdown, Control