The ALDH1A1 Knockout DLD-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human colorectal adenocarcinoma DLD-1 cell line, featuring targeted disruption of the ALDH1A1 gene. This polyclonal pool consists of a heterogeneous mixture of cells carrying diverse editing events at the ALDH1A1 locus, resulting in loss of function of the encoded aldehyde dehydrogenase enzyme. The product is provided as a ready-to-use knockout model for investigating ALDH1A1-dependent pathways in colorectal cancer biology. By employing CRISPR/Cas9-mediated gene disruption, this cell population offers a convenient and robust tool for studying ALDH1A1 function without the need for clonal selection.
The DLD-1 cell line is a well-established model of human colorectal adenocarcinoma, originally isolated from a primary tumor of a colorectal cancer patient. These epithelial cells harbor critical mutations in tumor suppressors and oncogenes: a truncating mutation in APC, an activating G13D substitution in KRAS, and a mutation in TP53, which collectively recapitulate the genetic abnormalities frequently observed in colorectal tumors. DLD-1 cells exhibit transformed characteristics and are tumorigenic, making them suitable for both in vitro and xenograft-based studies of colorectal cancer pathogenesis. Their epithelial origin and defined genetic background provide a reliable platform for dissecting gene function in the context of colorectal adenocarcinoma.
ALDH1A1 encodes a cytosolic aldehyde dehydrogenase that catalyzes the irreversible oxidation of retinaldehyde to retinoic acid, the active metabolite of vitamin A. Retinoic acid subsequently binds to nuclear retinoic acid receptors (RAR??, RXR??) and triggers transcriptional regulation of target genes, including HOX cluster members and RAR??. ALDH1A1 expression is transcriptionally regulated by TCF/LEF transcription factors downstream of Wnt/??-catenin signaling, as well as by Notch1 intracellular domain and NF-??B, linking retinoid biosynthesis to stem cell maintenance and inflammatory pathways. Functionally, ALDH1A1 interacts with related isoforms ALDH1A2 and ALDH1A3, retinol dehydrogenases, and cellular retinoic acid binding proteins (CRABP1/2) that modulate retinoic acid availability. Through retinoic acid production, ALDH1A1 influences ??-catenin stability and transcriptional activity, thereby promoting the expression of cyclin D1 and stem cell markers CD133 and CD44. This places ALDH1A1 at the nexus of retinoic acid signaling, Wnt/??-catenin, and cancer stem cell regulatory networks.
In DLD-1 colorectal cancer cells, ALDH1A1 activity contributes to a stem-like phenotype and chemoresistance, partly through detoxification of endogenous and xenobiotic aldehydes and modulation of retinoic acid-dependent gene expression. Disruption of ALDH1A1 in this cell line abolishes retinoic acid biosynthesis, dampens RAR/RXR-mediated transcription, and potentially attenuates ??-catenin-driven proliferation and stemness. This polyclonal knockout model enables researchers to examine the role of ALDH1A1 in maintaining cancer stem cell properties within a genetically defined adenocarcinoma background. Given the mutant APC and KRAS status, the cells provide a relevant context for investigating the crosstalk between hyperactivated Wnt signaling and retinoic acid pathways, as well as evaluating the impact on drug resistance mechanisms commonly observed in colorectal tumors.
This knockout cell population is designed for a wide range of research applications, including mechanistic studies of retinoic acid signaling, cancer stem cell biology, and drug resistance. Researchers can employ the ALDEFLUOR assay to confirm loss of ALDH enzymatic activity, use flow cytometry to assess expression of stemness markers such as CD133 and CD44, and quantify retinoic acid levels by LC-MS. Western blotting for ??-catenin and cyclin D1 enables evaluation of downstream signaling effects, while cell proliferation, migration, and invasion assays facilitate functional phenotypic analysis. The model is also well suited for high-throughput drug screening aimed at identifying compounds that target ALDH1A1-dependent pathways. For further technical assistance or to explore custom applications, please contact Ascent Research.
