The Hectd2 Knockout EO771 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population derived from the mouse mammary carcinoma cell line EO771, in which the Hectd2 gene has been disrupted to create a loss-of-function model. This polyclonal knockout product enables the study of HECTD2??s role in cellular processes without the need for clonal isolation, providing a heterogeneous population with targeted gene disruption.
EO771 is a well-established murine mammary adenocarcinoma cell line originating from a spontaneous tumor in a C57BL/6 mouse, widely employed as a model for triple-negative breast cancer (TNBC). Its basal-like, aggressive phenotype and compatibility with syngeneic immunocompetent hosts make EO771 particularly valuable for investigating tumor biology, immune interactions, and therapeutic responses in a physiologically relevant context.
HECTD2 encodes an E3 ubiquitin ligase of the HECT domain family that functions critically in the DNA damage response and p53 tumor suppressor pathway. Upon genotoxic stress, the upstream kinase ATM/ATR activates p53, which transcriptionally upregulates HECTD2. HECTD2 then targets GTSE1 for ubiquitin-mediated degradation, relieving GTSE1-mediated inhibition of p53 and therefore amplifying p53 transcriptional activity. This positive feedback loop enhances expression of downstream effectors such as p21 and BAX, promoting cell cycle arrest and apoptosis. Additionally, HECTD2 ubiquitinates proliferating cell nuclear antigen (PCNA), contributing to the regulation of DNA damage tolerance and genome stability. HECTD2 also interacts with MDM2, the principal negative regulator of p53, further integrating its function into the p53 signaling network.
In the context of the EO771 triple-negative breast cancer model, disruption of HECTD2 offers a powerful tool to dissect the ubiquitin-dependent mechanisms governing p53 pathway regulation and DNA damage responses. Triple-negative breast cancers often exhibit defective p53 signaling or aberrant DNA repair, and HECTD2??s position as a p53-inducible E3 ligase that modulates both the amplitude and duration of p53 activity makes this knockout model highly relevant. By eliminating HECTD2 function, researchers can investigate how loss of this ubiquitin ligase impacts p53-mediated transcriptional programs, cellular sensitivity to DNA-damaging agents, and tumorigenic potential. This model is particularly suited for studies examining the interplay between ubiquitin-mediated proteolysis and tumor suppression in breast cancer cells.
Researchers can employ the Hectd2 Knockout EO771 Polyclonal Cells in a broad range of functional assays. Western blotting and RT-qPCR can validate altered expression of HECTD2, GTSE1, p53, p21, and PCNA, while flow cytometry permits analysis of cell cycle distribution and apoptosis induction. Immunofluorescence studies can reveal changes in subcellular localization of p53 and GTSE1. Clonogenic survival and proliferation assays are suitable for testing sensitivity to genotoxic chemotherapeutics or targeted agents, and in vivo xenograft experiments allow assessment of tumor growth kinetics. The model also provides a platform for identifying novel HECTD2 substrates and for profiling drug resistance mechanisms in triple-negative breast cancer. For additional information or to discuss custom applications, please contact Ascent Research.
