Peptide name : Ant-Bak

Source/Organism : Effectors (BAK, BAX)

Linear/Cyclic : Linear

Chirality : L

Peptide length: 35

C-terminal modification: Linear

N-terminal modification : Not found

Non-natural peptide information: None

Assay type : Not specified

Assay time : Not found

Activity : IC50 : 82 µM

Cell line : UM-22A

Cancer type : Head and neck squamous cell carcinomas (HNSCC)

Other activity : Not found

Amino acid composition bar chart :

Molecular mass : 4404.1827 Dalton

Aliphatic index : 0.78

Instability index : 51.18

Hydrophobicity (GRAVY) : -1.028

Isoelectric point : 11.728

Charge (pH 7) : 7.7573

Aromaticity : 0.114

Molar extinction coefficient (cysteine, cystine): (12490, 12490)

Hydrophobic/hydrophilic ratio : 0.84210526

hydrophobic moment : -0.710

Missing amino acid : C,H,T,P,E,S

Most occurring amino acid : R

Most occurring amino acid frequency : 6

Least occurring amino acid : F

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.2, 0.2, 0.3)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)[C@H](C)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](CCCNC(=N)N)NC(=O)CNC(=O)[C@@H](NC(=O)[C@H](CCC(N)=O)NC(=O)CNC(=O)[C@H](CCSC)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCCCN)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCSC)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@@H](NC(=O)[C@H](CCCCN)NC(=O)[C@@H](NC(=O)[C@H](CCC(N)=O)NC(=O)[C@@H](N)CCCNC(=N)N)[C@@H](C)CC)[C@@H](C)CC)C(C)C)C(=O)N[C@H](C(=O)NCC(=O)N[C@@H](CC(=O)O)C(=O)N[C@@H](CC(=O)O)C(=O)N[C@H](C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](Cc1ccc(O)cc1)C(=O)O)[C@@H](C)CC)[C@@H](C)CC

1 : Li R, et al. Targeting antiapoptotic Bcl-2 family members with cell-permeable BH3 peptides induces apoptosis signaling and death in head and neck squamous cell carcinoma cells. Neoplasia. 2007; 9:801-11. doi: 10.1593/neo.07394

Paper title : Targeting antiapoptotic Bcl-2 family members with cell-permeable BH3 peptides induces apoptosis signaling and death in head and neck squamous cell carcinoma cells.

Doi : https://doi.org/10.1593/neo.07394

Abstract : Head and neck squamous cell carcinomas (HNSCC) are frequently characterized by chemotherapy and radiation resistance, and by overexpression of Bcl-XL, an antiapoptotic member of the Bcl-2 protein family. In this report we examined whether cell-permeable peptides derived from the BH3 domains of proapoptotic Bax, Bad, or Bak could be used to target Bcl-XL and/or Bcl-2 in HNSCC cells, and induce apoptotic death in these cells. To render the peptides cell permeable, Antennapedia (Ant) or polyarginine (R8) peptide transduction domains were fused to the amino termini. Fluorescence microscopy of peptide-treated HNSCC cells revealed that the BH3 peptides colocalized with mitochondria, the site of Bcl-XL and Bcl-2 expression. By contrast, a mutant peptide (BaxE BH3) which cannot bind Bcl-XL or Bcl-2 was diffusely localized throughout the cytoplasm. Treatment of three HNSCC cell lines (1483, UM-22A, UM-22B) with the wild-type BH3 peptides resulted in loss of viability and induction of apoptosis, as assessed by MTS assays and annexin V staining. In general, Ant-conjugated peptides were more potent than R8-conjugated peptides, and Bad BH3 peptide was typically more potent than Bax BH3 or Bak BH3. Treatment of purified HNSCC mitochondria with BH3 peptides resulted in robust release of cytochrome c. Thus, the relative apoptosis resistance of HNSCC cells is not due to a deficit in this step of the intrinsic, mitochondrial-mediated apoptosis pathway. We conclude that cell-permeable BH3 peptides can be used to target Bcl-XL and/or Bcl-2 in HNSCC, and targeting of these proteins may have therapeutic value in the treatment of this disease.