10058-F4: c-Myc-Max Dimerization Inhibitor for Apoptosis & AML Research

Executive Summary: 10058-F4 is a cell-permeable small-molecule inhibitor that disrupts c-Myc/Max dimerization, leading to the suppression of c-Myc-dependent transcription and induction of apoptosis in hematological and solid tumor models (Stern et al., 2024). By specifically targeting the protein-protein interaction interface, it inhibits downstream targets such as PGC-1β and modulates Bcl-2 family proteins, resulting in mitochondrial-mediated cell death. Efficacy has been demonstrated in vitro in AML cell lines (e.g., HL-60, U937, NB-4) and in vivo in SCID mouse prostate cancer xenografts. Optimized for research, 10058-F4 is soluble in DMSO and ethanol, but not in water, and is available from APExBIO (Product page). This article summarizes the biological rationale, mechanism, benchmarks, and integration tips for translational oncology workflows.

Biological Rationale

The c-Myc transcription factor is a master regulator of cellular growth, metabolism, and proliferation. Its oncogenic activity is strictly dependent on dimerization with Max, a process required for DNA binding and transcriptional activation of pro-survival genes (Stern et al., 2024). Aberrant c-Myc expression is implicated in over 50% of human cancers, including acute myeloid leukemia (AML) and prostate cancer. Targeting the c-Myc/Max interaction is a direct strategy for disrupting oncogenic signaling without affecting upstream pathways. 10058-F4 was developed to selectively inhibit this interaction, providing a molecular tool for interrogating c-Myc-driven transcriptional programs. In particular, c-Myc regulates genes involved in DNA repair, cell cycle progression, and apoptosis resistance, such as TERT, PGC-1β, and Bcl-2 family members. Disruption of the c-Myc/Max axis sensitizes cancer cells to apoptosis and impairs tumor progression (Disrupting c-Myc/Max: Strategic Pathways). This article extends prior reviews by integrating new mechanistic and workflow data relevant to translational research.

Mechanism of Action of 10058-F4 C-Myc-Max dimerization inhibitor

10058-F4 ((5E)-5-[(4-ethylphenyl)methylidene]-2-sulfanylidene-1,3-thiazolidin-4-one) binds the c-Myc bHLH-LZ domain, preventing heterodimer formation with Max. This blocks c-Myc DNA binding, leading to downregulation of c-Myc-dependent transcription. In cancer cells, this results in:

• Suppression of genes critical for metabolic reprogramming (e.g., PGC-1β).
• Reduced c-Myc mRNA and protein levels via destabilization of the oncogenic transcriptional network.
• Cell cycle arrest at G1/S transition.
• Induction of apoptosis through mitochondrial mechanisms, including decreased Bcl-2, increased Bax, and cytochrome C release.

This mechanism has been validated in AML cell lines and SCID mouse xenograft models, as detailed in published and internal benchmarks (10058-F4: c-Myc-Max Dimerization Inhibitor for Apoptosis; this review extends mechanistic focus to workflow integration).

Evidence & Benchmarks

• 10058-F4 inhibits c-Myc/Max dimerization, blocking c-Myc DNA binding and transcriptional activation in vitro (Stern et al., 2024).
• In AML cell lines (HL-60, U937, NB-4), 10058-F4 induces G1 cell cycle arrest and apoptosis via the mitochondrial pathway (Advanced c-Myc-Max Dimerization Inhibitor for AML).
• Treatment of SCID mice bearing DU145 or PC-3 prostate cancer xenografts (20-30 mg/kg daily, IV, 2 weeks) led to significant tumor growth inhibition, with model-dependent efficacy (APExBIO product page).
• 10058-F4 downregulates anti-apoptotic Bcl-2, upregulates pro-apoptotic Bax, and triggers cytochrome C release, confirming mitochondrial pathway activation (Unraveling c-Myc/Max Disruption for Precision Apoptosis).
• Compound is soluble at ≥24.9 mg/mL in DMSO, ≥2.64 mg/mL in ethanol; insoluble in water (APExBIO).
• RNA-seq analyses from APEX2 knockdown support c-Myc's role in regulating gene expression at repetitive DNA loci relevant to telomerase (TERT) activity (Stern et al., 2024).

Applications, Limits & Misconceptions

10058-F4 is validated for:

• Acute myeloid leukemia (AML) cell line research and apoptosis assays.
• Prostate cancer xenograft models in immunodeficient mice.
• Dissecting c-Myc/Max signaling and mitochondrial apoptosis pathways.
• Investigating transcription factor inhibition and Bcl-2 family regulation.
• Experimental hematology and translational oncology workflows.

This article clarifies and updates prior application guides such as Disrupting the c-Myc/Max Axis: Strategic Guidance, by integrating recent TERT transcriptional regulation insights relevant for stem cell and aging studies.

Common Pitfalls or Misconceptions

• 10058-F4 is not recommended for diagnostic or medical treatment; research use only.
• Compound is insoluble in water; improper vehicle selection impairs assay reproducibility.
• Long-term storage of working solutions (>weeks) leads to compound degradation; prepare fresh aliquots.
• Efficacy varies between tumor models; results from AML may not extrapolate directly to solid tumors.
• Not all c-Myc functions are Max-dependent; residual transcriptional activity may persist in some contexts.

Workflow Integration & Parameters

• Stock solutions: Dissolve 10058-F4 at ≥12.5 mg/mL in DMSO; warming to 37°C or sonication increases solubility (APExBIO).
• Storage: -20°C for several months; avoid repeated freeze-thaw cycles.
• Working concentrations: Titrate in the range of 10–50 µM for in vitro assays; adjust for cell density and model.
• For in vivo: Dose at 20–30 mg/kg daily IV in mouse models; consult institutional protocols for pharmacokinetic optimization.
• Shipping: Product supplied as a solid, shipped on blue ice by APExBIO.
• Include appropriate vehicle controls (DMSO or ethanol, matched final concentration).

Conclusion & Outlook

10058-F4, available from APExBIO, is a well-characterized, cell-permeable small-molecule inhibitor that enables precise disruption of the c-Myc/Max axis in cancer research. Its validated activity in AML and prostate cancer models, robust mechanistic data, and defined physicochemical parameters make it a preferred tool for apoptosis and transcription factor inhibition workflows. Further integration with telomerase/TERT pathway studies may open new avenues for understanding stem cell biology and age-related disease (Stern et al., 2024). For detailed protocols and ordering, visit the 10058-F4 C-Myc-Max dimerization inhibitor product page.