The 41701 antibody, cataloged by Novus Biologicals, is a monoclonal antibody targeting phosphorylated epidermal growth factor receptor (EGFR) at the Thr654 residue. EGFR, a transmembrane tyrosine kinase receptor, plays a critical role in regulating cell proliferation, survival, and differentiation. Phosphorylation at Thr654 occurs following receptor activation, a key step in downstream signaling pathways like MAPK/ERK and PI3K/Akt, which are often dysregulated in cancers. The 41701 antibody (clone 17A6. mouse IgG1 host) is designed to detect this phosphorylation event, enabling researchers to study EGFR activation status in various contexts. It is validated for applications including Western blotting (WB) and immunohistochemistry (IHC), making it a valuable tool for investigating EGFR signaling dynamics in cancer models, particularly in studies exploring therapeutic resistance or response to EGFR-targeted therapies (e.g., tyrosine kinase inhibitors). Dysregulated EGFR signaling is implicated in numerous malignancies, including lung, colorectal, and breast cancers, underscoring the antibody’s relevance in both basic and translational research. By specifically recognizing the phosphorylated Thr654 epitope, the 41701 antibody aids in elucidating mechanisms of oncogenic signaling and evaluating potential biomarkers for targeted treatment strategies. Its utility extends to preclinical studies assessing drug efficacy or resistance mechanisms linked to EGFR pathway activation.