Heat shock protein 70 (Hsp70) membrane expression on head-and-neck cancer biopsy-a target for natural killer (NK) cells.
OBJECTIVE
Heat shock protein 70 (Hsp70) was detected on the cell membrane of human tumor cell lines, but not on normal cells. Here we studied Hsp70 membrane expression as a target for natural killer (NK) cells on tumor material and control tissues of head-and-neck cancer patients.


METHODS
Membrane-bound Hsp70 was determined by flow cytometry on single-cell suspensions of tumors and the corresponding normal tissues of head-and-neck cancer patients. The cytolytic activity of NK cells against Hsp70-positive tumor cells was measured in a standard cytotoxicity assay.


RESULTS
In total, 54 of 74 primary tumors were found to be Hsp70 membrane-positive (73%); tongue/mouth, 21 of 24 (88%); oropharynx, 13 of 20 (65%); hypopharynx, 3 of 6 (50%); larynx, 8 of 11 (73%); trachea 1 of 2 (50%); esophagus, 4 of 5 (80%); lymph node metastases, 4 of 6 (67%). The corresponding control tissue was negative for membrane-bound Hsp70. Biopsies (6 of 6) of patients after in vivo gamma-irradiation (fractionated 5 x 2 Gy) were strongly Hsp70 membrane-positive. Irradiated, Hsp70-positive tumor cells are targets for Hsp70-peptide stimulated NK cells.


CONCLUSIONS
An irradiation-inducible, tumor-selective Hsp70 membrane localization provides a target structure for Hsp70-peptide stimulated human NK cells.
Kleinjung
Tobias
T
Department of Ear, Nose, and Throat Medicine (ENT), Regensburg, Germany.
Arndt
Olaf
O
Feldmann
Horst Jürgen
HJ
Bockmühl
Ulrike
U
Gehrmann
Mathias
M
Zilch
Tanja
T
Pfister
Karin
K
Schönberger
Johannes
J
Marienhagen
Jörg
J
Eilles
Christoph
C
Rossbacher
Lydia
L
Multhoff
Gabriele
G
D001706:Biopsy; D002294:Carcinoma, Squamous Cell / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D005434:Flow Cytometry; D018840:HSP70 Heat-Shock Proteins / Q000276:immunology* / Q000378:metabolism; D006258:Head and Neck Neoplasms / Q000276:immunology* / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy; D006801:Humans; D007111:Immunity, Cellular; D007694:Killer Cells, Natural / Q000502:physiology*
D018840:HSP70 Heat-Shock Proteins