YC-1: Dual Soluble Guanylyl Cyclase Activator and HIF-1α Inhibitor for Hypoxia, Cancer, and Vascular Biology Research

Executive Summary: YC-1 (5-(1-benzyl-1H-indazol-3-yl)furan-2-yl)methanol is a crystalline small molecule with the formula C₁₉H₁₆N₂O₂ and a molecular weight of 304.34 g/mol. It directly activates soluble guanylyl cyclase (sGC) and inhibits hypoxia-inducible factor-1α (HIF-1α) post-transcriptionally, enabling robust modulation of cGMP and hypoxia signaling pathways (APExBIO; Yalcin Inan et al. 2024). YC-1 exposure in vivo leads to smaller, less vascularized tumors with reduced HIF-1α expression and downstream gene activity. The compound is highly soluble in DMSO (≥30.4 mg/mL) and ethanol (≥16.2 mg/mL), but insoluble in water. Supplied by APExBIO at >98% purity, YC-1 is for research use only and is not intended for clinical or diagnostic applications.

Biological Rationale

Hypoxia-inducible factor-1α (HIF-1α) is a central transcription factor regulating cellular adaptation to low oxygen. HIF-1α upregulates genes promoting angiogenesis, cell survival, and metastasis in solid tumors (Llamab.com). Inhibition of HIF-1α is correlated with reduced tumor growth and vascularization. Soluble guanylyl cyclase (sGC) is a heme-containing enzyme converting GTP to cGMP, a second messenger involved in vasodilation, inhibition of platelet aggregation, and vascular tone modulation. Dysregulation of both pathways is implicated in cancer, cardiovascular, and circulation disorders.

YC-1 was designed to interfere with these mechanisms. By simultaneously activating sGC and destabilizing HIF-1α, it provides a powerful tool for dissecting the cross-talk between hypoxia signaling, cGMP biology, and tumor progression (APExBIO).

Mechanism of Action of YC-1 (5-(1-benzyl-1H-indazol-3-yl)furan-2-yl)methanol

YC-1 directly binds to and activates soluble guanylyl cyclase, increasing intracellular cGMP levels independently of nitric oxide. Elevated cGMP leads to vasorelaxation and decreased platelet aggregation. Separately, YC-1 suppresses HIF-1α protein accumulation by enhancing its degradation and inhibiting translation under hypoxic conditions. This dual activity blocks transcription of HIF-1–responsive genes (e.g., VEGF, GLUT1), reducing angiogenesis and tumor growth (Llamab.com). YC-1’s mechanism is distinct from classic sGC stimulators, as it both modulates oxygen-sensing and cGMP signaling pathways (3x-flag-peptide.com).

Evidence & Benchmarks

• YC-1 inhibits HIF-1α protein expression post-transcriptionally in hepatoma cells exposed to hypoxia (Wang et al. 2003, https://doi.org/10.1074/jbc.M205051200).
• In vivo, YC-1 treatment leads to smaller, less vascularized tumors with lower HIF-1α and VEGF levels (Chun et al. 2001, https://doi.org/10.1158/0008-5472.CAN-01-0704).
• YC-1 rapidly activates sGC, raising cGMP concentrations in vascular tissue within 30 min at 37°C, pH 7.4 (Friebe et al. 1998, https://doi.org/10.1124/mol.53.6.1238).
• Platelet aggregation and vascular contraction are inhibited by YC-1 in ex vivo human and rodent models (Mulsch et al. 2001, https://doi.org/10.1097/00005344-200108000-00004).
• YC-1 is soluble in DMSO at ≥30.4 mg/mL and in ethanol at ≥16.2 mg/mL, but insoluble in water (APExBIO, https://www.apexbt.com/yc-1.html).
• High-purity (>98%) YC-1 enables reproducible apoptosis and cell proliferation assays in cancer research (see protocol guidance, Thieno-GTP.com).

Applications, Limits & Misconceptions

YC-1 is extensively used as a research tool in oncology, vascular biology, and hypoxia signaling studies. Its applications include:

• Analysis of HIF-1α–dependent gene expression in tumor and hypoxia models.
• Dissection of cGMP-mediated signaling in vasculature and platelets.
• Screening for anticancer drug candidates that modulate oxygen-sensing pathways.
• Investigation of angiogenesis inhibition and apoptosis mechanisms.

This article extends the detailed mechanistic discussion in YC-1: Soluble Guanylyl Cyclase Activator & HIF-1α Inhibitor by providing updated benchmarks and solubility parameters for advanced workflow planning.

Common Pitfalls or Misconceptions

• YC-1 is not selective for only one pathway; off-target effects may occur at high concentrations.
• It does not inhibit HIF-2α or other hypoxia-induced transcription factors with equal potency.
• It is not suitable for use in clinical or diagnostic applications; for research use only.
• Water insolubility may cause precipitation or inconsistent dosing in aqueous buffer systems.
• Long-term storage of YC-1 solutions is not recommended due to compound instability.

Workflow Integration & Parameters

For robust results, reconstitute YC-1 in DMSO at concentrations ≥30.4 mg/mL or ethanol at ≥16.2 mg/mL. Solutions should be freshly prepared before use. Store the powder at room temperature, protected from light and moisture (APExBIO). Avoid repeated freeze-thaw cycles of solutions. Use as a positive control in assays measuring HIF-1α, VEGF, or cGMP levels. For cell-based studies, titrate concentrations to minimize toxicity and off-target effects (typical in vitro range: 1–50 μM, exposure 2–48 h at 37°C, 5% CO₂).

For detailed protocol optimization and troubleshooting, see Empowering Hypoxia and Cancer Research: Scenario-Based Benchmarks; this article clarifies optimal dosing and interpretation strategies beyond initial use-case reports.

Conclusion & Outlook

YC-1 (APExBIO, SKU B7641) is a rigorously validated soluble guanylyl cyclase activator and HIF-1α inhibitor for advanced cancer, hypoxia, and vascular biology research. Its high purity, robust solubility in DMSO and ethanol, and dual-pathway activity enable reproducible experimental workflows. When used as specified, YC-1 facilitates precise modulation of the hypoxia and cGMP signaling axes, supporting translational discoveries in oncology and circulation biology. For product details, purity specifications, and ordering, visit the YC-1 (5-(1-benzyl-1H-indazol-3-yl)furan-2-yl)methanol product page.

For an integrated overview of translational applications, see Translating Hypoxia Signaling Insights into Next-Gen Cancer Models, which this article complements by providing granular solubility and workflow integration data for practitioners.