The ID3 Knockout SK-OV-3 Polyclonal Cells product comprises a heterogeneous polyclonal cell population derived from SK-OV-3 human ovarian adenocarcinoma cells, engineered via CRISPR/Cas9-mediated disruption of the ID3 gene locus. This gene-edited pool enables loss-of-function studies of the dominant-negative helix-loop-helix (HLH) protein ID3 in an epithelial cancer background. As a polyclonal knockout resource, it circumvents clonal selection biases, providing a broad representation of ID3-disrupted genotypes suitable for pooled functional screens, bulk omics analyses, and high-throughput phenotypic assays where population-level responses to ID3 ablation are interrogated. The cells are supplied as a ready-to-use format with validated target-gene disruption, supporting immediate application in mechanistic cancer research without requiring additional editing steps.
The parental SK-OV-3 cell line is a well-characterized human ovarian adenocarcinoma model initially isolated from the ascites of a patient with serous cystadenocarcinoma. SK-OV-3 cells exhibit epithelial morphology, anchorage-independent growth, and resistance to multiple chemotherapeutic agents, making them a robust platform for studying high-grade serous ovarian cancer biology. They harbor mutations in key tumor suppressors such as TP53 and maintain active signaling through the PI3K/Akt and MAPK pathways. Their extensively documented genomic and proteomic landscape, along with established xenograft tumorigenicity, positions SK-OV-3 as a valuable host for gene-editing approaches aimed at dissecting molecular drivers of ovarian cancer progression, metastasis, and drug resistance.
ID3 functions as a dominant-negative inhibitor of class I basic helix-loop-helix (bHLH) transcription factors, primarily by heterodimerizing with E-proteins such as E47 and HEB, thereby preventing their DNA binding and transcriptional activation. This ID3-driven repression blocks bHLH-dependent gene expression programs that promote lineage commitment and differentiation. Upstream, ID3 expression is strongly induced by TGF-beta and BMP cytokines through receptor-mediated SMAD2/3 activation, as well as by Notch signals and growth factors including EGF and VEGF. Downstream, ID3 transcriptionally represses cell cycle inhibitors p21 and p16, while promoting Cyclin D1 expression, thus facilitating G1/S transition. Additionally, ID3 suppresses epithelial markers like E-cadherin and upregulates pro-invasive factors such as VEGF and matrix metalloproteinases (MMPs). ID3 can also interact with non-bHLH partners, including the retinoblastoma protein (Rb) and the transcription factor Ets-1, further integrating into proliferative and migratory control networks.
In the SK-OV-3 ovarian cancer context, ID3 is frequently overexpressed, contributing to enhanced proliferation, compromised differentiation, and an invasive mesenchymal-like phenotype. CRISPR/Cas9-mediated disruption of ID3 in these cells is predicted to derepress bHLH transcription factors, restoring their ability to drive cell cycle arrest and differentiation programs. Consequently, this polyclonal knockout model is expected to exhibit attenuated cell cycle progression, elevated expression of p21 and p16, reduced Cyclin D1 levels, and impaired migration and invasion due to downregulation of MMPs and VEGF. The model also provides a unique tool to interrogate the rewiring of TGF-beta and BMP signaling pathways upon loss of their downstream effector ID3, potentially unmasking compensatory or antithetical responses in the PI3K/Akt circuit. Such molecular phenotypes make this system highly relevant for dissecting the role of ID3 in ovarian cancer maintenance and progression.
This ID3 knockout polyclonal cell population is a versatile reagent for a spectrum of cancer research applications. Researchers can employ it in functional assays such as colony formation, migration, and invasion studies to directly assess the contribution of ID3 to tumorigenic behavior. The model is compatible with flow cytometry-based cell cycle analysis and Western blotting or RT-qPCR quantification of downstream target modulation. For therapeutic development, it serves as a genetic validation tool for ID3-targeted interventions and can be integrated into drug synergy screens with standard-of-care chemotherapeutics. Xenograft tumor growth studies using these cells enable in vivo examination of ID3-dependent tumor initiation and metastatic colonization. For further details or to discuss custom assay implementation, please contact Ascent Research.
