INPP5B Knockout HT29 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HT29 human colorectal adenocarcinoma cell line. This product provides a genetically heterogeneous pool of cells in which the INPP5B gene has been disrupted, enabling loss-of-function studies without clonal selection. The polyclonal format preserves the biological variability inherent in the parental line while eliminating functional INPP5B expression, making it suitable for assays where population-level responses are informative.
The HT29 cell line, established from a 44-year-old female patient, is an adherent epithelial model widely used to study colorectal cancer. These cells harbor a BRAF V600E mutation and are microsatellite stable, distinguishing them from mismatch repair-deficient lines. HT29 cells are particularly valued for their ability to form polarised monolayers and produce mucins, recapitulating aspects of intestinal epithelial barrier function. This background provides a physiologically relevant context for examining how INPP5B loss impacts colorectal tumor cell behavior.
INPP5B encodes an inositol polyphosphate-5-phosphatase that hydrolyzes the 5-phosphate group of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3). Functioning downstream of receptor tyrosine kinases such as the insulin receptor and EGFR, INPP5B counteracts PI3K activity to limit AKT phosphorylation and subsequent signaling through targets including GSK3, PKC, and mTORC1. The enzyme interacts with clathrin adaptor complexes, ARHGAP21, and 14-3-3 proteins, and regulates actin dynamics via cofilin and profilin. Through these interactions, INPP5B modulates endocytosis, cytoskeletal rearrangement, and proliferative signals.
In the HT29 adenocarcinoma context, knockout of INPP5B is anticipated to elevate PI(3,4,5)P3 levels and sustain AKT activation, thereby augmenting downstream survival and proliferation pathways. Given the coexisting BRAF V600E mutation, this model allows dissection of cross-talk between MAPK and PI3K signaling. Enhanced AKT signaling may also alter mucin production and epithelial integrity, highlighting the model’s utility for exploring how phosphoinositide metabolism influences colon cancer progression and therapeutic resistance.
Researchers can employ these polyclonal knockout cells to investigate roles of INPP5B in insulin and growth factor signaling, endocytosis, and cytoskeletal dynamics. Representative assays include Western blotting for phospho-AKT (Ser473), phospho-GSK3??, and phospho-S6; immunofluorescence for actin stress fibers; cell migration and invasion tests; and PIP mass ELISA. The model is also applicable for screening resistance mechanisms to PI3K pathway inhibitors. For further details or custom projects, please contact Ascent Research.
