10058-F4: c-Myc-Max Dimerization Inhibitor for Apoptosis and Leukemia Research

Executive Summary: 10058-F4 is a validated small-molecule inhibitor that selectively blocks c-Myc-Max heterodimerization, thereby suppressing c-Myc-dependent gene activation in cancer cells [APExBIO]. The compound induces mitochondrial apoptosis via modulation of Bcl-2 family proteins and cytochrome C release in acute myeloid leukemia (AML) cell lines [Stern et al., 2024]. Its efficacy is demonstrated in vitro and in vivo, including significant tumor reduction in SCID mouse xenograft models. 10058-F4 is highly soluble in DMSO (≥24.9 mg/mL) and is recommended for short-term storage at -20°C. This article extends evidence from prior reviews by focusing on mechanistic, workflow, and practical limits for translational research use cases.

Biological Rationale

c-Myc is a pivotal oncoprotein and transcription factor that regulates genes involved in cell proliferation, metabolism, and apoptosis. Its activity depends on heterodimerization with Max, which allows DNA binding and transcriptional activation of downstream targets such as PGC-1β. Dysregulation of c-Myc is observed in diverse cancers, including acute myeloid leukemia and prostate carcinoma. Inhibiting c-Myc-Max interaction disrupts oncogenic transcriptional programs, leading to cell cycle arrest and apoptosis [Stern et al., 2024]. Genetic and pharmacological evidence indicate that targeting the c-Myc/Max axis is a promising strategy in experimental hematology and oncology.

Mechanism of Action of 10058-F4 C-Myc-Max Dimerization Inhibitor

10058-F4, chemically (5E)-5-[(4-ethylphenyl)methylidene]-2-sulfanylidene-1,3-thiazolidin-4-one, binds selectively to the c-Myc protein. This interaction blocks the formation of the c-Myc/Max heterodimer. As a result, c-Myc fails to bind DNA, preventing transcriptional activation of target genes, including those regulating cell proliferation (e.g., PGC-1β), survival, and metabolic pathways. In AML cell lines (HL-60, U937, NB-4), 10058-F4 decreases c-Myc mRNA and protein levels, induces cell cycle arrest, and triggers apoptosis via the mitochondrial (intrinsic) pathway. Apoptosis is marked by decreased Bcl-2, increased Bax, and cytochrome C release from mitochondria. These effects culminate in reduced cancer cell viability and promote myeloid differentiation [Related Review].

Evidence & Benchmarks

• 10058-F4 inhibits c-Myc/Max heterodimerization in vitro with high selectivity, preventing c-Myc binding to E-box DNA motifs (Stern et al., 2024, https://doi.org/10.1101/2024.09.23.614488).
• Application of 10058-F4 to AML cell lines (HL-60, U937, NB-4) at 25–40 μM for 24–72 hours results in decreased c-Myc mRNA and protein levels, cell cycle arrest (G1), and increased apoptosis (APExBIO, https://www.apexbt.com/10058-f4.html).
• Mitochondrial apoptosis is evidenced by downregulation of Bcl-2, upregulation of Bax, and cytochrome C release upon compound treatment (Stern et al., 2024, https://doi.org/10.1101/2024.09.23.614488).
• In vivo, intravenous administration of 10058-F4 (20–30 mg/kg daily for two weeks) in SCID mice bearing DU145 or PC-3 prostate cancer xenografts achieved significant but model-variable tumor control (APExBIO, https://www.apexbt.com/10058-f4.html).
• 10058-F4 displays high solubility in DMSO (≥24.9 mg/mL), moderate solubility in ethanol (≥2.64 mg/mL), and is insoluble in water, informing preparation and storage strategies (APExBIO, https://www.apexbt.com/10058-f4.html).

This article provides detailed mechanistic context absent from previous summaries, which focused on application workflows rather than molecular specificity.

Applications, Limits & Misconceptions

10058-F4 is broadly used in cancer biology to interrogate c-Myc-driven pathways, particularly in acute myeloid leukemia and prostate cancer research. It is also employed in apoptosis assays to dissect the mitochondrial apoptotic response. The compound is cell-permeable and suitable for both in vitro (cell culture) and in vivo (xenograft) studies. However, its use is strictly for scientific research and not for diagnostic or therapeutic application. Efficacy may vary between cancer models due to differences in c-Myc dependency.

This article clarifies the mechanistic limits and proper parameterization of 10058-F4, expanding on the scenario-driven guidance in related reviews by providing data-backed boundaries for experimental design.

Common Pitfalls or Misconceptions

• 10058-F4 is not water-soluble; attempts to dissolve in aqueous media without co-solvent will fail.
• The inhibitor is not suitable for long-term storage in solution; precipitation or degradation may occur.
• 10058-F4 does not inhibit c-Myc activity in all cell types equally; responsiveness depends on c-Myc/Max dependence.
• It is not intended for clinical or diagnostic use; all applications are for research only.
• 10058-F4 does not target other Myc family members (e.g., N-Myc, L-Myc) with equal affinity.

Workflow Integration & Parameters

For optimal experimental results, prepare stock solutions of 10058-F4 in DMSO at concentrations above 12.5 mg/mL. Solubilization can be aided by warming to 37°C or brief sonication. Working solutions should be freshly prepared before use. For cell-based assays, typical working concentrations range from 10–40 μM. For in vivo use, doses of 20–30 mg/kg administered intravenously daily for two weeks have been validated in mouse models [10058-F4 C-Myc-Max dimerization inhibitor, APExBIO]. Store solid compound at -20°C; avoid repeated freeze-thaw cycles. Do not store diluted solutions for extended periods. The compound is shipped on blue ice to maintain stability during transit. For troubleshooting and advanced workflow design, see the extended discussion in related technical articles.

Conclusion & Outlook

10058-F4, as provided by APExBIO, remains a robust, cell-permeable small-molecule inhibitor ideal for dissecting c-Myc-Max signaling in cancer research. Its validated action in AML and prostate cancer models, coupled with clear solubility and handling parameters, supports reproducible apoptosis induction and cell cycle arrest studies. Further research will clarify its utility in additional cancer contexts and in combinatorial regimens targeting transcription factor networks. For detailed product information and ordering, visit the 10058-F4 C-Myc-Max dimerization inhibitor product page.