Journal: Oncogene
Article Title: Transglutaminase 2 promotes tumorigenicity of colon cancer cells by inactivation of the tumor suppressor p53
doi: 10.1038/s41388-021-01847-w
Figure Lengend Snippet: A – C HCT-116 p53 wildtype cells (wt) and HCT-116 p53 knockout cells (−/−) were transduced with either shTGM2-1, shTGM2-2, or shSCRMBL. Time-lapse imaging and proliferation assay were performed to determine a rescue from cell death upon TGM2 knockdown. A Fold change of cell number of HCT-116 p53 wt and HCT-116 p53 −/− cells upon TGM2 knockdown in comparison to shSCRMBL control determined at day three after transduction. Data are presented as mean ± SD of three independent experiments (** P < 0.01, Mann–Whitney U test). B Single cell tracking of HCT-116 p53 wt and HCT-116 p53 − /− cells after TGM2 knockdown with shTGM2-1 and (C) shTGM2-2. Cumulative cell death events are shown over time (*** P < 0.001, Log-rank test). D Direct visualization of p53 activation upon TGM2 knockdown by time-lapse video-microscopy. Sequence of phase contrast images, tdTOMATO fluorescence of shTGM2-1 and p53-driven destabilized GFP reporter , depicting the same field of view over the time course of 30 hours as indicated in the corresponding panels in I–VIII. The yellow circles designate tracked cells over time. (I–VIII) show corresponding sequence of fluorescence images taken at the same time points as the phase contrast images. (I) Shown are two representative HCT-116 cells. (II and III) 6-8 hours after lentiviral transduction of shTGM2-1 both HCT-116 cells express the red fluorescent tdTOMATO reporter, indicating a knockdown of TGM2. (IV-VI) Another 4–10 hours later both cells express the green fluorescent (GFP) p53 reporter, indicating the induction of p53 activity. (VII and VIII) About 24 hours after transduction both HCT-116 cells subsequently undergo apoptosis (white arrows). Movie S shows all assembled images (3 min temporal resolution) of the same sequence.
Article Snippet: The human colorectal cancer cell lines SW480 and HCT-116 were obtained from CLS Cell Lines Service GmbH (Eppelheim, Germany).
Techniques: Knock-Out, Transduction, Imaging, Proliferation Assay, MANN-WHITNEY, Single Cell Tracking, Activation Assay, Microscopy, Sequencing, Fluorescence, Activity Assay