Peptide Schedule
PNC-2731 residues (approx.)PQHLRVKRPQHLRVRQIKIWFQNRRMKWKKEach bubble = one amino acid. Size = residue mass. Color = chemical class.Uses closest standard amino acids for non-standard residues.PNC-27
Benefits
About PNC-27
PNC-27 is a 32-residue synthetic anticancer peptide engineered from two functional domains: the p53 transactivation domain (residues 12-26) responsible for binding HDM-2 (the human homologue of MDM2), and a cell-penetrating peptide (CPP) leader sequence derived from Drosophila Antennapedia that enables membrane interaction. The peptide was developed primarily by researchers at SUNY Downstate Medical Center and has been studied since the mid-2000s. PNC-27 exploits a key difference between cancer cells and normal cells — cancer cells express significant amounts of HDM-2 protein on their outer plasma membranes, while normal cells do not. When PNC-27 encounters a cancer cell, the p53-derived domain binds to membrane-associated HDM-2 in approximately 1:1 stoichiometric complexes. These complexes then aggregate within the membrane to form large ring-shaped transmembrane pores with interior diameters averaging 34.5 nm. The pore formation process is temperature-dependent: PNC-27 binds to HDM-2 at any temperature, but the lateral diffusion, aggregation, and pore assembly require physiological temperature (37 degrees C). Once pores form, the cancer cell membrane loses integrity, causing rapid necrotic cell death — not apoptosis — with detectable LDH release within 4 hours. Preclinical studies have demonstrated PNC-27 activity against breast cancer (MDA-MB-231), pancreatic cancer (MIA PaCa-2), melanoma (A2058), multiple leukemia cell lines (U937, OCI-AML3, HL-60), cervical cancer, and patient-derived epithelial ovarian cancer cells. In an in vivo mouse model, PNC-27 was administered daily via intraperitoneal injection with a maximum tolerated dose of 2 mg/day. It also enhanced paclitaxel activity in a mouse ovarian cancer model, producing greater tumor reduction than either agent alone. A 2024 study revealed that PNC-27 also disrupts mitochondrial membranes in cancer cells, suggesting a dual-mechanism of action. Despite these promising preclinical results, no human clinical trials have been completed, and all safety and dosing information remains speculative.
Who Should Consider PNC-27
- Researchers studying HDM-2/MDM2 biology and cancer cell membrane targeting
- Oncology research labs investigating selective anticancer peptides
- Preclinical investigators exploring combination therapy with chemotherapy agents
- Not suitable for the general population — preclinical compound with no human safety or efficacy data
- Not for use in pregnant or breastfeeding women — no reproductive toxicity data exists
How PNC-27 Works
PNC-27 exploits the aberrant surface expression of HDM-2 (human double minute 2, the human analogue of murine MDM2) on cancer cell plasma membranes. Normal cells express HDM-2 only in the nucleus and cytoplasm, but many cancer cell types display HDM-2 at significant levels on their outer membrane surface. The p53-derived domain of PNC-27 (residues 12-26) binds to this membrane-associated HDM-2, forming 1:1 complexes. The CPP leader sequence of PNC-27 points away from the binding interface, oriented toward the membrane interior. After initial binding (which is temperature-independent), the PNC-27:HDM-2 complexes undergo lateral diffusion and aggregate within the lipid bilayer at physiological temperature (37 degrees C). This aggregation produces ring-shaped transmembrane pores with interior diameters of 28-44 nm, lined by alternating PNC-27 and HDM-2 molecules. These large pores destroy membrane integrity, causing rapid necrotic cell lysis with LDH release detectable within hours. A 2024 study also showed PNC-27 interacts with mitochondrial membranes in cancer cells, causing mitochondrial disruption as a secondary death pathway. Because normal cells lack surface HDM-2, PNC-27 has no binding target and leaves them unharmed — a finding confirmed by transfection experiments showing that normal cells engineered to express membrane HDM-2 become susceptible to PNC-27.
What to Expect
Initial dosing phase. No observable effects expected in a clinical sense, as PNC-27 has only been studied in cell culture and animal models. In vitro, cancer cell lysis occurs within 4-24 hours of peptide exposure. Injection site reactions are possible.
Continued administration. In the murine ovarian cancer model, tumor growth reduction was observed during this timeframe when PNC-27 was combined with paclitaxel. Any human response at this stage is entirely speculative.
Extended administration phase. In preclinical studies, sustained daily dosing was required to achieve maximal cancer cell killing due to the short half-life of the peptide. Monitoring for any adverse effects is strongly recommended.
Recovery period. No data exists on what happens after cessation of PNC-27 treatment. Off-cycle observation allows assessment of any delayed effects and recovery from potential subclinical toxicity.
Dosing Protocol
| Level | Dose / Injection | Frequency |
|---|---|---|
| Beginner | 100mcg | Daily |
| Moderate | 250mcg | Daily |
| Aggressive | 500mcg | Daily |
Note: Experimental anticancer peptide — preclinical only with zero completed human trials. Contains residues 12-26 of p53 (the HDM-2/MDM2 binding domain) fused to a cell-penetrating leader sequence. Selectively kills cancer cells by binding to HDM-2 on their plasma membranes and forming transmembrane pores, while leaving normal cells unaffected. All dosing is theoretical and extrapolated from in vitro concentrations and a single murine MTD study. Not FDA-approved for any indication.
How to Inject PNC-27
All dosing is experimental and extrapolated from preclinical data only. If used in a research context, administer subcutaneously with rotation of injection sites between abdomen, outer thigh, and upper arm. Reconstitute with bacteriostatic water — do not shake, swirl gently. Daily injections appear necessary based on the short estimated half-life. In murine studies, intraperitoneal injection was the route used. Start at the lowest dose tier and monitor carefully. There is no established safe human dose.
Cycling Protocol
Cycling protocols are entirely theoretical. In vitro studies used continuous daily peptide addition over the course of experiments, suggesting frequent dosing is needed due to short half-life. The murine MTD study used daily intraperitoneal injections. No established human cycling protocol exists. Extended breaks between cycles are advisable given the complete absence of long-term safety data.
Pharmacokinetics
Source: Estimated from in vitro peptide stability; no formal PK studies in humans or animals. In cell culture, daily re-addition of peptide was needed for full effect, suggesting rapid degradation.
Loading the interactive decay curve.
Side Effects
No human clinical safety data exists. In a murine study, the maximum tolerated dose via intraperitoneal injection was 2 mg/day, with dose-limiting toxicities observed at higher doses. Potential risks include injection site reactions, inflammatory responses from tumor cell necrosis (tumor lysis-like effects), and unknown off-target effects on tissues that may express low levels of membrane HDM-2. Rapid cancer cell death could release cellular contents and cause metabolic disturbances. Long-term safety in any species is not well characterized. This peptide has not been evaluated for reproductive toxicity, genotoxicity, or carcinogenicity.
Contraindications
- Pregnancy or breastfeeding — no reproductive or developmental toxicity data exists
- Active autoimmune conditions — tumor necrosis may trigger unpredictable immune activation
- Severe hepatic or renal impairment — impaired clearance of necrotic cell debris and metabolites
- Known hypersensitivity to PNC-27 or any excipients
- Concurrent use of MDM2/HDM2 inhibitors — direct pathway overlap with unknown interaction effects
- Tumor lysis syndrome risk — patients with high tumor burden may be at elevated risk from rapid cell death
- Children and adolescents — no pediatric safety data of any kind
Drug Interactions
- MDM2/HDM2 inhibitors (nutlins, idasanutlin, milademetan) — direct target overlap could amplify or interfere with PNC-27 binding
- Paclitaxel and other chemotherapy agents — additive antitumor effects observed in preclinical models but combined toxicity is not characterized in humans
- Immunosuppressants (cyclosporine, tacrolimus) — may impair immune clearance of necrotic tumor debris
- Anticoagulants (warfarin, heparin) — tumor cell necrosis may release procoagulant factors, altering bleeding risk
- Other membrane-active peptides (LL-37, melittin) — overlapping membrane disruption mechanisms could increase off-target toxicity
- Corticosteroids — may blunt immune-mediated clearance of dead tumor cells
Storage & Stability
Molecular Profile
Related Peptides
References
- Anticancer peptide PNC-27 adopts an HDM-2-binding conformation and kills cancer cells by binding to HDM-2 in their membranesPubMed 20080680
- The anti-cancer peptide, PNC-27, induces tumor cell lysis as the intact peptidePubMed 20182728
- The anti-cancer peptide, PNC-27, induces tumor cell necrosis of a poorly differentiated non-solid tissue human leukemia cell line that depends on expression of HDM-2 in the plasma membrane of these cellsPubMed 25117093
- Ex vivo Efficacy of Anti-Cancer Drug PNC-27 in the Treatment of Patient-Derived Epithelial Ovarian CancerPubMed 26663795
- Synergy between Paclitaxel and Anti-Cancer Peptide PNC-27 in the Treatment of Ovarian CancerPubMed 28667027
- Targeting Membrane HDM-2 by PNC-27 Induces Necrosis in Leukemia Cells But Not in Normal Hematopoietic CellsPubMed 32878773
- PNC-27, a Chimeric p53-Penetratin Peptide Binds to HDM-2 in a p53 Peptide-like Structure, Induces Selective Membrane-Pore Formation and Leads to Cancer Cell LysisPubMed 35625682
- Anti-Cancer Peptide PNC-27 Kills Cancer Cells by Unique Interactions with Plasma Membrane-Bound hdm-2 and with Mitochondrial Membranes Causing Mitochondrial DisruptionPubMed 38802154