Table 1.
HKDC1-based peptides induce cell death in MNCs from ENKTL patients and SNK6 cells.
| Peptide name | Peptide sequence | AA | IC50 (µM) | |
|---|---|---|---|---|
| ENKTL | SNK6 | |||
| Antp-HKC8 | RQIKIWFQNRRMKWKK-LQQAQKEN | 24 | 1.3 ± 0.4 (n = 3) | 1.3 ± 0.3 (n = 4) |
| Antp-D-HKC8 | RQIKIWFQNRRMKWKK-LQQAQKEN | 24 | 1.0 ± 0.3 (n = 3) | 1.2 ± 0.4 (n = 3) |
| PAS-HKC8 | GKPILFF-LQQAQKEN | 15 | 1.4 ± 0.4 (n = 4) | 1.4 ± 0.3 (n = 3) |
| PAS-D-HKC8 | GKPILFF-LQQAQKEN | 15 | 1.1 ± 0.3 (n = 3) | 1.3 ± 0.3 (n = 4) |
| TAT-HKC8 | GYGRKKRRQRRRG-LQQAQKEN | 21 | 1.9 ± 0.4 (n = 4) | 2.0 ± 0.4 (n = 3) |
| TAT-D-HKC8 | GYGRKKRRQRRRG-LQQAQKEN | 21 | 1.5 ± 0.7 (n = 4) | 1.7 ± 0.5 (n = 4) |
| Tf-HKC8 | HAIYPRH-LQQAQKEN | 15 | 0.5 ± 0.2 (n = 3) | 0.7 ± 0.2 (n = 3) |
| Tf-Scram | HAIYPRH-EILNKEKK | 15 | >15.0 (n = 3) | >15.0 (n = 3) |
| Tf-D-HKC8 | HAIYPRH-LQQAQKEN | 15 | 0.2 ± 0.1 (n = 5) | 0.3 ± 0.2 (n = 5) |
| Tf-D-Scram | HAIYPRH-EILNKEKK | 15 | >15.0 (n = 3) | >15.0 (n = 3) |
| Tf-HKC15 | HAIYPRH-ITAVAKRLQQAQKEN | 22 | 1.2 ± 0.4 (n = 3) | 1.4 ± 0.3 (n = 3) |
| Tf-D-HKC15 | HAIYPRH-ITAVAKRLQQAQKEN | 22 | 0.9 ± 0.3 (n = 3) | 1.2 ± 0.5 (n = 3) |
| Tf-D-Scram | HAIYPRH-NAAAKLAVEILNKEK | 22 | >15.0 (n = 3) | >15.0 (n = 3) |
| Tf-HKN15 | HAIYPRH-MFAVHLMAFYFSKLK | 22 | >15.0 (n = 3) | >15.0 (n = 3) |
| Tf-D-HKN15 | HAIYPRH-MFAVHLMAFYFSKLK | 22 | >15.0 (n = 3) | >15.0 (n = 3) |
Cells were incubated with different concentrations of peptides (0.1–15 µM) for 6 h. The half-maximal cell death activity (IC50) value was determined by PI staining with subsequent FACS analysis. Results are expressed as mean ± SEM. The cell-penetrating sequence is underlined, the HKDC1-based targeting sequences are in italics, and the amino acids in the D-configuration are marked in bold.
AA amino acid numbers of peptides, Antp a 16 penetrating residue long sequence from the Drosophila antennapedia-homeodomain, D D-configuration, all the D-amino acids were synthesized as retro-inverso peptides, HKC8 last eight aa of the C-terminal in human HKDC1, HKC15 last 15 aa of the C-terminal in human HKDC1, HKN15 first 15 aa of the N-terminal in human HKDC1, IC50 half-maximal cell death activity value, PAS penetration-accelerating segment, Scram scramble peptide sequence, TAT HIV-1 TAT sequence, Tf transferrin receptor internalization sequence.