The GPX1 Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human colorectal adenocarcinoma cell line HT29. This product consists of a heterogeneous pool of cells with targeted disruption of the GPX1 gene, providing a loss-of-function model that retains cellular diversity. It is suitable for studying bulk oxidative stress responses and pathway modulation without clonal selection artifacts.
The HT29 cell line is an adherent, epithelial model originally derived from a primary colorectal adenocarcinoma of a 44-year-old Caucasian female. HT29 cells are extensively used to investigate intestinal biology and colon cancer mechanisms, featuring characteristic mutations in tumor suppressors and oncogenes such as APC, KRAS, and TP53. Their well-documented differentiation capacity and sensitivity to oxidative stress make them an ideal host for studying antioxidant gene functions.
GPX1 encodes a selenium-dependent glutathione peroxidase that catalyzes the reduction of hydrogen peroxide and lipid hydroperoxides to water and alcohols using glutathione (GSH). Expression of GPX1 is transcriptionally regulated by the stress-responsive transcription factor NRF2, which is normally sequestered by KEAP1 and released under oxidative conditions. Upstream regulators include TP53 and selenium availability. Downstream, GPX1 attenuates the NF-??B and MAPK pathways and inhibits ferroptosis by limiting lipid peroxidation. The knockout of GPX1 abolishes this critical antioxidant defense, leading to elevated ROS, increased lipid peroxidation, and sensitization to ferroptotic and apoptotic signals.
The combination of GPX1 knockout with the HT29 colorectal cancer background allows dissection of redox-dependent tumor biology. HT29 cells harbor a TP53 mutation, which can modulate NRF2 activity and alter baseline oxidative stress, thereby accentuating the impact of GPX1 loss. This polyclonal knockout population facilitates robust pathway analysis, enabling researchers to examine the interplay between p53, NRF2 signaling, and ferroptosis sensitivity in colon carcinoma. The model is particularly relevant for studying how GPX1 deficiency influences chemoresistance and tumor cell survival under oxidative insult.
Applications include quantification of reactive oxygen species (ROS) using fluorescent probes, measurement of glutathione levels, analysis of lipid peroxidation markers following ferroptosis induction with agents such as erastin or RSL3. Western blotting and RT-qPCR enable assessment of downstream signaling components including NF-??B and MAPK phosphorylation. Cell viability assays under oxidative stress or ferroptosis inducers characterize GPX1’s cytoprotective role. These cells are valuable for drug resistance studies testing pro-oxidant chemotherapeutics in colorectal cancer. For further information and technical support, please contact Ascent Research.
