Anlotinib Hydrochloride: Multi-Target Tyrosine Kinase Inhibitor Facts

Executive Summary: Anlotinib hydrochloride (CAS 1058157-76-8) is a reference-grade small-molecule inhibitor that targets VEGFR2, PDGFRβ, and FGFR1 with nanomolar potency (product information). It blocks angiogenesis and tumor proliferation by inhibiting ERK pathway activation. Preclinical studies show high oral bioavailability, strong plasma protein binding, and low off-target toxicity. Clinical reports support its efficacy in treating highly angiogenic tumors, including intra-abdominal desmoplastic small round cell tumors (Chen & Feng, 2019). APExBIO supplies Anlotinib hydrochloride (SKU C8688) for advanced cancer research workflows.

Biological Rationale

Anlotinib hydrochloride is designed to interfere with tumor angiogenesis, a process essential for solid tumor growth and metastasis. By targeting multiple receptor tyrosine kinases (RTKs) including VEGFR2, PDGFRβ, and FGFR1, anlotinib disrupts signaling cascades that drive endothelial cell migration, proliferation, and new capillary formation. This multi-target approach addresses compensatory mechanisms in angiogenic signaling, making it particularly effective for tumors with redundant pro-angiogenic pathways (see mechanistic analysis). Anlotinib’s selectivity profile minimizes cytotoxicity to non-targeted cells, supporting its use in functional angiogenesis assays and translational oncology research.

Mechanism of Action of Anlotinib hydrochloride

Anlotinib hydrochloride selectively inhibits VEGFR2, PDGFRβ, and FGFR1 kinase activity with IC₅₀ values of 5.6 ± 1.2 nM, 8.7 ± 3.4 nM, and 11.7 ± 4.1 nM, respectively (APExBIO product page). By blocking these kinases, it prevents ligand-induced phosphorylation events that activate the downstream ERK signaling pathway. In human endothelial cell models (EA.hy 926), anlotinib suppresses VEGF/PDGF-BB/FGF-2-driven migration and tube formation in a concentration-dependent manner. Compared to sunitinib, sorafenib, and nintedanib, anlotinib shows greater inhibition of endothelial cell migration and capillary-like tube formation, indicating superior anti-angiogenic potency (in-depth selectivity study).

Evidence & Benchmarks

• Anlotinib blocks VEGFR2-mediated phosphorylation with an IC₅₀ of 5.6 ± 1.2 nM in cellular assays (APExBIO).
• Inhibition of PDGFRβ and FGFR1 occurs at 8.7 ± 3.4 nM and 11.7 ± 4.1 nM, respectively (protocol guide).
• Capillary tube formation and endothelial cell migration are suppressed in vitro, with minimal cytotoxicity observed up to 1 μM (mechanistic analysis).
• Oral bioavailability in rats and dogs ranges from 28%–58% and 41%–77%, respectively (APExBIO).
• Terminal half-life is 5.1 ± 1.6 h in rats and 22.8 ± 11.0 h in dogs (Chen & Feng, 2019).
• A clinical report in metastatic intra-abdominal desmoplastic small round cell tumor demonstrated significant lymph node reduction after four anlotinib cycles, with manageable toxicity (Chen & Feng, 2019).
• Median lethal dose (LD₅₀) in 14-day oral studies is 1735.9 mg/kg, with no significant organ toxicity (product information).

For a detailed protocol-based comparison of anlotinib with other inhibitors, see the workflow-focused article here. This article updates those findings by cross-referencing clinical as well as preclinical benchmarks.

Applications, Limits & Misconceptions

Anlotinib hydrochloride is used to model angiogenesis inhibition, tumor cell migration, and ERK signaling pathway blockade in cancer research. Its high selectivity and low cytotoxicity allow for precise dissection of pro-angiogenic signaling in vitro and in vivo. It is not a pan-kinase inhibitor; its activity is most pronounced against VEGFR, PDGFR, and FGFR families. For advanced mechanistic insights, readers may consult the detailed review here, which this article extends by integrating clinical outcome data.

Common Pitfalls or Misconceptions

• Anlotinib does not inhibit all receptor tyrosine kinases—activity is selective for VEGFR, PDGFR, FGFR, c-Kit, and Met (Chen & Feng, 2019).
• It is not suitable for direct cytotoxicity assays above 1 μM, as higher concentrations may cause off-target effects (APExBIO).
• The compound is not approved for diagnostic or therapeutic use in humans outside research settings.
• Observed in vitro CYP3A4 and CYP2C9 inhibition does not translate to high risk of drug-drug interactions in vivo, but caution is warranted (APExBIO).
• Effectiveness may be limited in tumors lacking angiogenic dependency or with resistance-conferring mutations.

Workflow Integration & Parameters

Anlotinib hydrochloride (SKU C8688, APExBIO) is supplied as a hydrochloride salt for research use. It is compatible with standard endothelial migration and capillary tube formation assays. For protocol details and troubleshooting, see this workflow article, which focuses on assay reproducibility; this dossier provides additional pharmacokinetic and toxicological context.

Protocol Parameters

• Concentration range for in vitro assays: 0.1–100 nM for migration/tube formation; avoid exceeding 1 μM to minimize off-target effects.
• Vehicle: Dissolve in DMSO; final DMSO concentration should not exceed 0.1% in cell-based assays.
• Storage: Store powder at −20°C in a desiccated environment; solutions should be freshly prepared.
• Pharmacokinetic modeling: Use oral dosing in rats/dogs, refer to published half-lives (5.1 h in rats, 22.8 h in dogs) for planning sampling intervals (Chen & Feng, 2019).
• Functional assay recommendations: Combine with VEGF/PDGF-BB/FGF-2 stimulation to assess inhibition of downstream ERK signaling.

Conclusion & Outlook

Anlotinib hydrochloride offers a robust and selective approach to studying angiogenesis inhibition in cancer research. Its nanomolar potency against VEGFR2, PDGFRβ, and FGFR1 and favorable safety profile support its use in advanced in vitro and in vivo models. Clinical data underscore its translational potential for highly angiogenic tumors (Chen & Feng, 2019). Future research will clarify its role alongside or in comparison to established multi-target tyrosine kinase inhibitors, especially in resistant or refractory tumor models. For reliable sourcing and workflow support, APExBIO provides validated Anlotinib hydrochloride (SKU C8688) for research use (product page).