RESUMO
PURPOSE: 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 AND MATERIALS: 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. CONCLUSION: An irradiation-inducible, tumor-selective Hsp70 membrane localization provides a target structure for Hsp70-peptide stimulated human NK cells.
Assuntos
Carcinoma de Células Escamosas/imunologia , Proteínas de Choque Térmico HSP70/imunologia , Neoplasias de Cabeça e Pescoço/imunologia , Células Matadoras Naturais/fisiologia , Biópsia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Membrana Celular/imunologia , Membrana Celular/metabolismo , Citometria de Fluxo , Proteínas de Choque Térmico HSP70/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Imunidade CelularRESUMO
OBJECTIVE: To determine the safety and efficacy of targeted antitumor therapy with cisplatin/epinephrine injectable gel in patients with advanced squamous cell carcinoma of the head and neck. DESIGN: Two prospective, double-blind, placebo-controlled phase III trials of identical design. Crossover from blinded to open-label phase was permitted for patients with disease progression. SETTING: Tertiary referral centers in North America and Europe. PATIENTS: One hundred seventy-nine intensively pretreated patients with recurrent or refractory squamous cell carcinoma of the head and neck. INTERVENTION: Cisplatin/epinephrine injectable or placebo gel was administered by direct intratumoral injection; up to 6 weekly treatments. Dose was 0.25 mL of active or placebo gel per cubic centimeter of tumor up to 10 mL total. Patient benefit after local tumor control of the most symptomatic tumor was assessed by patients and physicians using the Treatment Goals Questionnaire. MAIN OUTCOME MEASURES: Local tumor response and patient benefit attributable to improvements in tumor-related symptoms. RESULTS: Combined results for the 178 patients with evaluable data in the 2 trials confirmed objective tumor responses in 35 (29%) of 119 patients, including 23 (19%) complete responses achieved with cisplatin/epinephrine gel, vs 1 (2%) of 59 for placebo (P<.001). Tumor response and patient benefit were significantly correlated (P=.006): 47% (17/36) of patients with target tumor responses achieved a rigorously defined benefit based on a prospectively selected treatment goal vs 15% (22/142) of nonresponders. CONCLUSION: Cisplatin/epinephrine injectable gel reduces tumor burden, ameliorates tumor symptoms, and provides a new therapeutic option for treating patients with squamous cell carcinoma of the head and neck.