Peptide name : R8-BidBH3Alt

Source/Organism : Synthetic Peptide

Linear/Cyclic : Linear

Chirality : Mix

Peptide length: 29

C-terminal modification: Linear

N-terminal modification : Free

Non-natural peptide information: None

Assay type : MTT/MTS assay

Assay time : 8h

Activity : 2% apoptosis at 50 µM

Cell line : IMR5

Cancer type : Tumor

Other activity : Not found

Amino acid composition bar chart :

Molecular mass : 3530.0092 Dalton

Aliphatic index : 0.641

Instability index : 164.024

Hydrophobicity (GRAVY) : -1.551

Isoelectric point : 12

Charge (pH 7) : 7.8522

Aromaticity : 0

Molar extinction coefficient (cysteine, cystine): (0, 0)

Hydrophobic/hydrophilic ratio : 1.1

hydrophobic moment : 0.1681

Missing amino acid : C,W,T,P,K,F,Y,L

Most occurring amino acid : r

Most occurring amino acid frequency : 8

Least occurring amino acid : E

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.2, 0.2, 0.1)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@@H](NC(=O)[C@@H](NC(=O)[C@H](CC(=O)O)NC(=O)[C@H](CCC(=O)O)NC(=O)CNC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@@H](N)CCCNC(=N)N)[C@@H](C)CC)[C@@H](C)CC)C(=O)N[C@@H](C)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](Cc1c[nH]cn1)C(=O)N[C@@H](C)C(=O)N[C@@H](C)C(=O)N[C@@H](CCC(N)=O)C(=O)N[C@H](C(=O)NCC(=O)N[C@@H](C)C(=O)N[C@@H](CO)C(=O)N[C@@H](CCSC)C(=O)N[C@@H](CC(=O)O)C(=O)N[C@@H](CCCNC(=N)N)C(=O)O)C(C)C

1 : Goldsmith KC, et al. BH3 peptidomimetics potently activate apoptosis and demonstrate single agent efficacy in neuroblastoma. Oncogene. 2006; 25:4525-33. doi: 10.1038/sj.onc.1209489

Paper title : BH3 peptidomimetics potently activate apoptosis and demonstrate single agent efficacy in neuroblastoma.

Doi : https://doi.org/10.1038/sj.onc.1209489

Abstract : The major impediment to cure for many malignancies is the development of therapy resistance with resultant tumor progression. Genetic alterations leading to subversion of inherent apoptosis pathways are common themes in therapy resistance. Bcl-2 family proteins play a critical role in regulating mitochondrial apoptosis that governs chemotherapeutic effects, and defective engagement of these pathways contributes to treatment failure. We have studied the efficacy of BH3 peptidomimetics consisting of the minimal death, or BH3, domains of the proapoptotic BH3-only proteins Bid and Bad to induce apoptosis using neuroblastoma (NB) as a model system. We demonstrate that BH3 peptides, modified with an arginine homopolymer for membrane transduction (called r8-BidBH3 and r8-BadBH3, respectively), potently induce apoptosis in NB cells, including those with MYCN amplification. Cell death is caspase 9 dependent, consistent with a requirement for the intrinsic mitochondrial pathway. Substitutions at highly conserved residues within the r8-BidBH3 peptide abolish apoptotic efficacy supporting activity through specific BH domain interactions. Concomitant exposure to r8-BadBH3 and r8-BidBH3 at sublethal monotherapy doses revealed potent synergy consistent with a competitive displacement model, whereby BH3 peptides displace sequestered BH3 proteins to induce cell death. Further, BH3 peptides demonstrate antitumor efficacy in a xenograft model of NB in the absence of additional genotoxic or trophic stressors. These data provide proof of principle that targeted re-engagement of apoptosis pathways may be of therapeutic utility, and BH3-like compounds are attractive lead agents to re-establish therapy-induced apoptosis in refractory malignancies.