The ALCAM knockout HT29 polyclonal cells represent a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HT29 human colorectal adenocarcinoma cell line, designed for targeted disruption of the ALCAM gene. This loss-of-function model is generated using CRISPR/Cas9-mediated gene disruption, enabling researchers to interrogate ALCAM-dependent processes in a physiologically relevant colon cancer context without the influence of clonal variation, as the polyclonal pool retains genetic heterogeneity beyond the targeted locus.
HT29 cells were originally established from a primary colorectal adenocarcinoma of a female patient and serve as a widely used intestinal epithelial cell line in cancer biology. These cells exhibit characteristics of undifferentiated colon carcinoma with the capacity to undergo enterocytic differentiation under specific conditions, making them a robust platform for studying colorectal cancer cell adhesion, migration, and metastatic dissemination. The HT29 line endogenously expresses ALCAM, thereby providing a relevant background for loss-of-function analysis.
ALCAM (CD166) is a cell adhesion molecule that mediates homophilic ALCAM-ALCAM interactions and heterophilic binding to CD6 and L1CAM, playing pivotal roles in leukocyte extravasation, T cell activation, and tumor progression. In cancer cells, ALCAM is transcriptionally regulated by the Wnt/??-catenin pathway via TCF/LEF factors and can be induced by inflammatory stimuli such as TNF-?? and IL-1??, as well as by EGF. Downstream, ALCAM engagement activates ERK1/2 phosphorylation, leading to upregulation of matrix metalloproteinases MMP-2 and MMP-9 and remodeling of the actin cytoskeleton through interactions with ezrin. In immune contexts, ALCAM co-stimulates T cell proliferation through CD6-mediated signaling involving ZAP70.
Disruption of ALCAM in HT29 cells provides a critical tool to dissect its dual role in tumor biology, where ALCAM overexpression is associated with enhanced invasion and metastasis, while its loss may impair cell-cell adhesion and transendothelial migration. This polyclonal knockout population is particularly valuable for studying colorectal cancer progression, as it enables assessment of ALCAM??s contribution to metastatic pathways in an intestinal epithelial background, including its interactions with CD6 and L1CAM and downstream ERK/MMP signaling cascades. Additionally, this model facilitates exploration of ALCAM??s involvement in inflammatory bowel disease and tumor-immune cell crosstalk.
Researchers can employ these ALCAM knockout cells in a variety of assays including transwell migration/invasion, cell adhesion, and co-culture with T cells to evaluate altered immune interactions. The model supports western blot validation using ALCAM-specific antibodies, RT-qPCR for transcript analysis, co-immunoprecipitation with CD6, and immunofluorescence to visualize adhesion complex dynamics. Flow cytometry enables quantification of surface ALCAM loss, while phospho-ERK analysis provides insight into downstream signaling perturbations, making this tool suitable for drug screening targeting ALCAM-dependent metastasis or immune modulation. For additional information or custom cell engineering, please contact Ascent Research.
