The HERPUD1 Knockout SK-HEP-1 Polyclonal Cells constitute a CRISPR/Cas9-edited polyclonal population of SK-HEP-1 cells with targeted disruption of the HERPUD1 gene. This loss-of-function model enables investigation of HERPUD1-dependent processes in a liver adenocarcinoma context. As a heterogeneous knockout pool, the cells provide a versatile system for bulk functional studies without potential artifacts from clonal selection.
SK-HEP-1 is a well-characterized human hepatocellular carcinoma cell line derived from the ascitic fluid of a patient with liver adenocarcinoma. These adherent cells exhibit epithelial morphology and are widely used in the study of liver cancer biology, including tumor growth, metabolism, and drug resistance. The hepatic origin and transformed phenotype make SK-HEP-1 an appropriate model in which to examine the consequences of HERPUD1 loss on cancer cell proteostasis.
HERPUD1 is an ER-resident protein induced by ER stress and a central component of ER-associated degradation (ERAD). Its expression is transcriptionally activated by ATF4, XBP1, and ATF6 downstream of the UPR sensors PERK and IRE1. At the ER membrane, HERPUD1 scaffolds the assembly of the HRD1?CSEL1L ubiquitin ligase complex, interacting with Derlin-1 and the AAA ATPase VCP/p97 to promote retrotranslocation and proteasomal degradation of misfolded substrates. By coupling stress sensing to ERAD, HERPUD1 mitigates ER stress and prevents sustained UPR signaling that can trigger apoptosis, with CHOP and BiP serving as key readouts of pathway activation.
In hepatocellular carcinoma, increased secretory load and oncogenic signaling impose chronic ER stress, and adaptive UPR responses are frequently co-opted to support tumor survival. HERPUD1 facilitates protein quality control, and its disruption can overwhelm the ERAD capacity of SK-HEP-1 cells, leading to accumulation of misfolded proteins and sensitization to apoptosis. Consequently, this knockout model offers a tool to explore how impaired proteostasis influences liver cancer cell fitness, chemosensitivity, and the balance between pro-survival and pro-death UPR outputs.
This polyclonal HERPUD1 knockout population is well suited for mechanistic studies of ER stress and ERAD. Typical applications include immunoblotting for HERPUD1 and UPR markers (BiP, CHOP), RT-qPCR analysis of UPR-regulated genes, and flow cytometric detection of apoptosis via Annexin V. Proteasome activity assays and co-immunoprecipitation of HERPUD1 with HRD1 or SEL1L can further define functional interactions. Together, these approaches enable dissection of ER proteostasis pathways, cancer cell responses to proteotoxic stress, and the evaluation of strategies targeting the ERAD machinery for therapeutic intervention. For further details, please contact Ascent Research.
