The ASAH1 Knockout SK-HEP-1 Polyclonal Cells are a CRISPR/Cas9-mediated polyclonal knockout cell population derived from the human hepatic adenocarcinoma cell line SK-HEP-1, featuring targeted disruption of the acid ceramidase (ASAH1) gene. This polyclonal pool provides a genetically heterogeneous loss-of-function model suitable for studying the cellular consequences of impaired ceramide hydrolysis in a liver cancer background. The knockout facilitates investigation of sphingolipid metabolism reprogramming and ceramide-dependent signaling without relying on pharmacological inhibition, offering a stable and reproducible platform for advanced biomedical research.
The SK-HEP-1 host cell line was originally established from the ascitic fluid of a patient with liver adenocarcinoma and is widely employed as a model for hepatocellular carcinoma, particularly for studying metastasis and drug resistance mechanisms. SK-HEP-1 cells display a mixed epithelial and mesenchymal phenotype, making them valuable for investigating epithelial-to-mesenchymal transition and tumor cell plasticity. Their well-characterized genomic background supports robust gene knockout studies for dissecting liver cancer pathways.
ASAH1 encodes the lysosomal enzyme acid ceramidase, which hydrolyzes ceramide into sphingosine and free fatty acid??a pivotal step in sphingolipid catabolism. This reaction is regulated by TFEB and Saposin D, which facilitate lysosomal function and substrate presentation. Loss of ASAH1 blocks ceramide degradation, leading to ceramide accumulation and reduced sphingosine-1-phosphate (S1P). Ceramide acts as a pro-apoptotic messenger via BAX/BCL-2, while S1P signals through S1PR1-5 to activate AKT and PKC??, promoting survival. Disruption thus shifts the ceramide-S1P rheostat toward apoptosis and autophagy. ASAH1 normally localizes to lysosomes, interacting with LAMP1 and LAMP2, and is part of a broader ceramidase family including ASAH2 and ACER1-3.
In the context of SK-HEP-1 hepatic adenocarcinoma cells, ASAH1 knockout drives ceramide accumulation and suppresses S1P-mediated oncogenic pathways, sensitizing the cells to chemotherapeutic agents such as doxorubicin. This model recapitulates key features of diseases associated with acid ceramidase deficiency, including Farber disease, a lysosomal storage disorder characterized by ceramide accumulation and severe inflammation. The polyclonal knockout population enables the study of heterogeneous responses to lipid stress, autophagy induction, and apoptotic signaling within a liver cancer milieu, making it a potent tool for dissecting sphingolipid-dependent mechanisms of drug resistance and tumor progression.
This polyclonal knockout model supports a broad range of applications, including ceramide LC-MS quantification, sphingosine-1-phosphate ELISA, and lipidomic profiling to characterize sphingolipid alterations. Apoptosis can be assessed by Annexin V/PI and caspase-3/7 assays, while autophagy is monitored via LC3 immunoblotting. It is particularly suited for doxorubicin sensitivity testing (MTT assay) and LAMP1 immunofluorescence to examine lysosomal integrity. Further applications include target validation for acid ceramidase inhibitors and western blot analysis of BCL-2, AKT, and PKC??. For further technical inquiries, please contact Ascent Research.
