The HSP90AB1 Knockout 143B Polyclonal Cells represent a heterogeneous pool of CRISPR/Cas9-edited human osteosarcoma cells carrying targeted disruption of the HSP90AB1 gene. This polyclonal population provides a genetically diverse loss-of-function model to study HSP90AB1-dependent cellular processes without isogenic selection, recapitulating the variability inherent in tumor cell populations. By eliminating functional HSP90AB1 protein, the product enables the systematic investigation of chaperone-dependent signaling networks in a TP53-mutant, highly metastatic cancer background.
The 143B parental line is a well-characterized human osteosarcoma cell line, originally derived from a patient tumor and widely used as a model for aggressive bone cancer. It harbors a TP53 mutation, which contributes to genomic instability and resistance to apoptosis, and exhibits pronounced metastatic behavior in vivo, making it particularly suitable for examining drivers of tumor progression and dissemination. The combination of TP53 deficiency and high metastatic potential creates a stringent cellular context for evaluating the functional impact of HSP90AB1 ablation.
HSP90AB1 encodes the constitutively expressed beta isoform of the heat shock protein 90 chaperone, which forms dynamic complexes with co-chaperones such as CDC37, AHA1, p23 (PTGES3), and FKBP5 to regulate the stability and activity of numerous client proteins. Through its ATP-dependent chaperone cycle, HSP90AB1 directly stabilizes critical oncogenic effectors including the serine/threonine kinases AKT1 and RAF1, the cell cycle regulator CDK4, and the transcription factor HIF1A, thereby integrating PI3K-Akt and HIF-1 signaling pathways. Under conditions of proteotoxic stress or elevated temperatures, its expression is upregulated by HSF1, reinforcing a cytoprotective network that enables malignant cells to cope with the hostile tumor microenvironment.
In the TP53-mutant 143B background, HSP90AB1 chaperone activity is essential for sustaining the aberrant stabilization and function of numerous oncogenic clients, including mutant TP53 itself, AKT1, RAF1, and CDK4. Disruption of HSP90AB1 abrogates this protective chaperoning, targeting these client proteins for proteasomal degradation and consequently impairing downstream proliferative and anti-apoptotic cascades. This knockout model thus recapitulates the profound cellular dependency of osteosarcoma cells on HSP90AB1 for maintaining protein homeostasis and aggressive growth, providing a powerful system to dissect the mechanistic basis of chaperone addiction in a highly metastatic context.
Researchers can employ this polyclonal knockout population in a variety of assays, including western blotting to assess client protein levels, cell viability and apoptosis assays to measure functional consequences of HSP90AB1 loss, and migration or invasion assays to interrogate metastatic capacity. Co-immunoprecipitation and proteasome activity assays can be used to further explore chaperone?Cclient interactions and degradation pathways. This product is ideally suited for functional investigations of the HSP90 chaperone cycle, validation of small-molecule HSP90 inhibitors, and studies of protein homeostasis in cancer metastasis. For further technical inquiries or ordering information, please contact Ascent Research.
