The Keap1 Knockout LLC Cell Line is a CRISPR/Cas9-edited murine lung carcinoma cell line with targeted disruption of the Keap1 gene. It serves as a loss-of-function model for studying the KEAP1 protein in a tumorigenic and metastatic background. By eliminating Keap1, this cell line enables investigation of NRF2-mediated antioxidant signaling and its implications in cancer cell redox homeostasis and drug response.
The parental LLC line originates from a spontaneously arising lung carcinoma in C57BL/6 mice and is an established syngeneic model of non-small cell lung carcinoma (NSCLC). Characterized by rapid tumor formation and high metastatic capacity, LLC cells provide a physiologically relevant system for examining gene function in lung cancer progression and therapy resistance.
Keap1 acts as a substrate adaptor for the CUL3?CRBX1 E3 ubiquitin ligase, mediating constitutive ubiquitination and proteasomal degradation of NRF2 under basal conditions. Upon oxidative or electrophilic stress, reactive cysteine residues in Keap1 are modified, releasing NRF2 to accumulate, translocate to the nucleus, and drive transcription of ARE-dependent cytoprotective genes such as NQO1, HO-1, and GCLC. The pathway is further regulated by interacting factors including p62/SQSTM1, which competes with NRF2 for Keap1 binding, and by upstream kinases like PKC and ERK.
In LLC cells, Keap1 knockout is predicted to cause constitutive NRF2 activation, a scenario that mirrors gain-of-function mutations in human lung cancers. This leads to enhanced expression of detoxifying enzymes and drug efflux transporters, conferring resistance to chemotherapeutics such as cisplatin. Thus, this knockout model is highly relevant for dissecting mechanisms of chemoresistance, redox adaptation, and the contribution of KEAP1?CNRF2 signaling to lung tumor aggressiveness and metastatic potential.
Applications include quantitative expression profiling of NRF2 targets by qRT-PCR and Western blotting, assessment of NRF2 localization via immunofluorescence, ARE-luciferase reporter assays for transcriptional activity, and cellular ROS measurements using DCFDA. The line is also suitable for drug sensitivity testing with oxidative stressors or anticancer agents, co-immunoprecipitation studies of KEAP1?CNRF2 complexes, and high-content screening of pathway modulators. For additional product information, please contact Ascent Research.
