New — Free Peptide Starter Guide (2026): 13 chapters, 34 cited studies

Get it free
ToolsComparePNC-27 vs Palmitoyl Tetrapeptide-7

PNC-27 vs Palmitoyl Tetrapeptide-7

Side-by-side comparison of key properties, dosing, and research.

Immune Support
PNC-27
Skin & Cosmetic
Palmitoyl Tetrapeptide-7
Summary
PNC-27 is a synthetic peptide derived from the p53 tumor suppressor protein, containing both an HDM2-binding domain and a transmembrane penetratin sequence. It selectively kills cancer cells by binding MDM2/HDM2 overexpressed on the plasma membrane of malignant cells, inducing membranolysis without harming normal cells.
Palmitoyl Tetrapeptide-7 (Rigin) is a cosmetic peptide consisting of palmitic acid linked to the tetrapeptide sequence GQPR (Gly-Gln-Pro-Arg). It was designed to mimic the biological activity of the IgG immunoglobulin C-terminus, which downregulates the production of interleukin-6 (IL-6), a key driver of skin aging and inflammation.
Half-Life
Not well established; estimated minutes to hours
Topical penetration-dependent; effects last hours to days
Admin Route
Intravenous (research), Intraperitoneal (research)
Topical
Research
Typical Dose
Not established for humans; research doses vary by cell line and model
2-5 ppm concentration in formulation
Frequency
Not established for human use
Twice daily
Key Benefits
  • Selective cytotoxicity against cancer cells overexpressing HDM2/MDM2
  • Spares normal cells lacking surface HDM2 expression
  • Membranolytic mechanism bypasses intracellular resistance pathways
  • Demonstrated activity against breast, pancreatic, leukemia, and melanoma cell lines
  • Potential for combination with conventional chemotherapy
  • Novel non-genotoxic anticancer mechanism
  • Reduces IL-6 inflammatory cytokine in skin
  • Prevents 'inflammaging' of the skin
  • Inhibits MMP collagen-degrading enzymes
  • Synergistic with Matrixyl for anti-aging
  • Clinically tested for wrinkle and skin texture improvement
  • Well-tolerated topically
Side Effects
  • Limited human clinical data; largely in vitro and animal studies
  • Potential immunogenic reactions (foreign peptide)
  • Systemic toxicity at high doses not well characterized
  • Unknown interactions with current chemotherapy agents
  • Contact sensitization (rare)
  • Well-tolerated at standard concentrations
Stacks With