Journal: Advanced science (Weinheim, Baden-Wurttemberg, Germany)
Article Title: LncRNA FAISL Inhibits Calpain 2-Mediated Proteolysis of FAK to Promote Progression and Metastasis of Triple Negative Breast Cancer.
doi: 10.1002/advs.202407493
Figure Lengend Snippet: Figure 3. FAISL stabilizes FAK protein and binds to Calpain 2. A–B) Western blot and quantification of FAK protein in TNBC cells after FAISL knockdown (A) or overexpression (B). C–D) Cycloheximide (CHX) chase assay of FAK in MDA-MB-231 cells. 100 μg mL−1 CHX was added to the culture medium after FAISL knockdown (C) or overexpressing (D). E) RNA pulldown using biotin-labeled FAISL and the LacZ mRNA (negative control) in MDA-MB-231 cells. The differential bands of the silver staining gel in the red frame were sent for mass spectrometry identification. F–G) Mass spectrometry profiles of FAISL-binding protein Calpain 2. H) RNA pulldown followed by western blot shows that FAISL binds to FAK and Calpain 2 in MDA-MB-231 cells. I) RNA immunoprecipitation followed by RT-qPCR in MDA-MB-231 cells using the anti-Flag antibody. MDA-MB-231 cells were transfected with Flag-FAK or Flag-Calpain 2. J–K) Cross-linking immunoprecipitation (CLIP) and RT-qPCR in MDA-MB-231 and MDA-MB-468 cells with the anti-Flag antibody. Cells were transfected with Flag-FAK (J) or Flag-Calpain 2 (K). L–M) Western blot (L) and quantification (M) of FAK protein in MDA-MB-231 treated with ALLM (10 μg mL−1, 12 h). Data are presented as mean ± SD of experimental triplicates (A–D, I–K, M). p values were determined using two-tailed Student’s t-test (A–D, I–K, M). (*p < 0.05, **p < 0.01, ***p < 0.001).
Article Snippet: Slides were soaked in 3% H2O2 for 10 min to eliminate endogenous peroxidase and blocked with 10% normal goat serum at room temperature for 30 min. Primary antibodies against FAK (CST, 71433S) (1:500) and Ki67 (CST, 9449T) (1:1000) were incubated overnight at 4 °C, and secondary antibodies for 60 min at 37 °C.
Techniques: Western Blot, Knockdown, Over Expression, Labeling, Negative Control, Silver Staining, Mass Spectrometry, Binding Assay, RNA Immunoprecipitation, Quantitative RT-PCR, Transfection, Cross-linking Immunoprecipitation, Two Tailed Test