The ATP6V1C2 Knockout SK-HEP-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal population of human SK-HEP-1 cells carrying a targeted disruption of the ATP6V1C2 gene. This loss-of-function model is designed to deconvolute the roles of the vacuolar ATPase (V-ATPase) V1 domain subunit C in lysosomal acidification and cellular pH control. The polyclonal format reflects the mixed editing outcomes from pooled CRISPR/Cas9 delivery, providing a versatile tool for functional studies without clonal artifacts.
The host cell line, SK-HEP-1, was derived from the ascites of a 52-year-old male with liver adenocarcinoma and is commonly used as a model for hepatic sinusoidal endothelium and hepatocellular carcinoma. These cells exhibit features of transformed hepatocytes and serve as a standard platform for investigating angiogenesis, metastasis, and drug resistance in liver cancer.
ATP6V1C2 encodes the C subunit of the V1 domain of V-ATPase, a multi-subunit proton pump essential for lysosomal and endosomal acidification. This subunit is critical for holoenzyme assembly and activity. Transcriptionally controlled by TFEB, ATP6V1C2 functions downstream of amino acid and growth factor signals and interacts with V1 subunits ATP6V1A, ATP6V1B, and ATP6V1D, as well as LAMP1 and syntenin-1. Its activity facilitates mTORC1 lysosomal recruitment via the Ragulator-Rag GTPase complex, thereby promoting mTORC1 phosphorylation of downstream targets like S6K. Consequently, ATP6V1C2 disruption impairs lysosomal acidification, leading to compromised autophagy flux (accumulation of LC3B-II and p62) and reduced cathepsin maturation. This dysregulation alters intracellular pH, integrin trafficking, and cell motility.
In hepatocellular carcinoma, V-ATPase activity is frequently elevated to support tumor metabolism, contributing to drug resistance and metastasis. Ablating ATP6V1C2 in SK-HEP-1 cells creates a disease-relevant model to study how V-ATPase-dependent pH regulation influences these malignant phenotypes. This system allows precise dissection of lysosomal contributions to autophagy, mTORC1 signaling, and chemosensitivity, particularly to sorafenib, within a cell line that recapitulates aspects of liver sinusoidal endothelium and tumor biology.
Investigators can utilize this knockout model in diverse assays: confirmatory western blotting or RT-qPCR, LysoSensor-based lysosomal pH measurements, immunoblotting for autophagy markers (LC3B, p62) and phospho-S6K, transwell migration tests, and sorafenib cytotoxicity assays. These tools support research into hepatocellular carcinoma pathobiology, V-ATPase inhibitor screening, and mechanisms of pH-dependent drug resistance. For additional information or custom inquiries, contact Ascent Research.
