The CAT Knockout SK-HEP-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population targeting the catalase (CAT) gene. This heterogeneous SK-HEP-1 cell pool exhibits disrupted catalase expression, providing a model for loss-of-function studies of this critical antioxidant enzyme. The knockout was generated via CRISPR/Cas9-mediated gene disruption, abolishing catalase activity. These cells enable investigations into oxidative stress response, redox signaling, and catalase-dependent pathways in cancer biology.
SK-HEP-1 is a well-characterized human liver adenocarcinoma cell line originally isolated from ascites fluid of a patient with liver adenocarcinoma. This adherent cell line displays epithelial and endothelial features and is extensively used as a model for hepatocellular carcinoma, tumor angiogenesis, and cancer metabolism studies. The liver adenocarcinoma origin provides a disease-relevant context for examining the impact of catalase loss on cancer cell oxidative stress handling and metabolic adaptation. SK-HEP-1 cells harbor genetic alterations that support uncontrolled growth, making them suitable for investigating how catalase deficiency influences proliferation and survival under oxidative challenges.
Catalase is a homotetrameric heme-containing peroxisomal enzyme that catalyzes the decomposition of hydrogen peroxide (H2O2) into water and oxygen, protecting cells from oxidative damage. Its expression is transcriptionally regulated by key factors including FOXO3, NFE2L2 (NRF2), and PPAR??, which respond to oxidative stress stimuli. The enzyme requires peroxin-5 (PEX5) for peroxisomal import and a heme prosthetic group for catalytic activity. Catalase functions within an antioxidant network that includes superoxide dismutase (SOD), glutathione peroxidase (GPX), and peroxiredoxin (PRDX), acting downstream of SOD to eliminate H2O2. Loss of catalase activity causes H2O2 accumulation, resulting in oxidative damage and activation of redox-sensitive MAPK pathways, including p-ERK and p-JNK signaling.
In the SK-HEP-1 liver adenocarcinoma background, catalase knockout elevates intracellular ROS levels, creating a pro-oxidative environment. This model allows dissection of how liver cancer cells adapt to heightened oxidative stress and how catalase deficiency affects cell survival, proliferation, and apoptosis. It is particularly valuable for studying the impact of catalase loss on drug sensitivity and xenobiotic metabolism, given the liver’s detoxifying role. The knockout cells also provide insights into diseases associated with impaired H2O2 detoxification, such as acatalasemia and age-related disorders. By exposing cells to exogenous H2O2 or other stressors, researchers can uncover compensatory redox mechanisms.
These polyclonal knockout cells support a broad range of applications, including investigation of oxidative stress pathways, ROS-mediated signaling in cancer, and drug sensitivity assays under oxidant conditions. Key techniques include Western blotting and RT-qPCR for confirming catalase depletion, catalase activity assays, ROS detection with DCFDA, and cell viability assessments under H2O2 challenge. Apoptosis evaluation by Annexin V/PI staining and phospho-signaling analysis of p-ERK and p-JNK further characterize the response to catalase loss. The model is also suitable for high-throughput screening of redox-modulating compounds. For further details or customized gene-editing services, please contact Ascent Research.
