The CBL Knockout SK-HEP-1 Polyclonal Cells comprise a population of human liver adenocarcinoma epithelial cells in which the CBL gene has been disrupted by CRISPR/Cas9-mediated gene editing. This polyclonal knockout product represents a heterogeneous pool of edited cells, providing a robust system for studying the loss-of-function effects of CBL in a hepatocellular carcinoma context. The use of CRISPR/Cas9 technology enables efficient target-gene disruption, generating a versatile model for investigating CBL-dependent signaling pathways.
The host cell line, SK-HEP-1, is a widely utilized model derived from the ascitic fluid of a patient with liver adenocarcinoma. These adherent epithelial cells are characterized by their tumorigenic properties and are extensively employed in cancer research to dissect mechanisms of hepatocarcinogenesis, drug resistance, and metastatic progression. The SK-HEP-1 background offers a clinically relevant platform for examining molecular alterations that drive aggressive liver cancer phenotypes.
CBL encodes an E3 ubiquitin-protein ligase that functions as a key negative regulator of receptor tyrosine kinase (RTK) signaling. Upon activation by upstream growth factors such as EGF and PDGF, or by SRC family kinases, receptor tyrosine kinases including EGFR, PDGFR, and MET become phosphorylated. CBL is recruited to these activated receptors via adaptor proteins such as GRB2, CRK, and CRKL, and mediates their ubiquitination in concert with cofactors like UBC13 and UBE2L3. This polyubiquitination targets the receptors for lysosomal degradation, thereby attenuating downstream cascades??including the RAS-RAF-ERK1/2 and PI3K-AKT pathways. In the absence of CBL, receptor degradation is impaired, leading to sustained signaling through GRB2, PI3K, and other effectors, resulting in prolonged activation of the MAPK/ERK and PI3K-AKT axes.
In the SK-HEP-1 hepatocellular carcinoma model, CBL knockout is expected to potentiate RTK-driven proliferative and survival signals, mirroring the dysregulated signaling often observed in liver cancer. This loss-of-function model is particularly relevant for investigating the role of CBL in tumorigenesis, metastasis, and acquired drug resistance. Moreover, CBL mutations have been implicated in hematological malignancies such as chronic myelomonocytic leukemia and acute myeloid leukemia, as well as in Noonan syndrome-like disorders; thus, the SK-HEP-1 knockout system provides a solid tumor context for comparative studies of CBL-dependent pathologies.
Researchers can employ these polyclonal knockout cells in a variety of functional assays to explore RTK signaling dynamics. Typical applications include western blot analysis of CBL protein levels and phosphorylation status of ERK1/2 and AKT, RT-qPCR quantification of CBL mRNA, EGFR degradation assays to assess receptor turnover, and cell-based assays to measure proliferation, apoptosis, migration, and invasion. This model is also suitable for drug screening campaigns aimed at identifying inhibitors that exploit CBL loss-induced signaling dependencies. For further technical details and ordering information, please contact Ascent Research.
