RESUMO
OBJECTIVE: Determine total plasminogen activator (PA) activity and urokinase-type plasminogen activator (u-PA) levels in cell-free supernatants derived from primary and metastatic squamous cell carcinoma of the head and neck. DESIGN: Plasminogen activator activity was measured by spectrophotometric assay with chromogenic substrate Val-Leu-Lys-para-nitroanilide. Urokinase-type plasminogen activator levels were measured with enzyme-linked immunosorbent assay technique. RESULTS: Fourteen established squamous cell carcinoma lines from patients with head and neck cancer were assayed for both total PA activity and u-PA levels at 24 to 48 hours of incubation. Compared with control and fibroblast-conditioned media, cell lines established from squamous cell carcinoma of the head and neck had significantly (P < .005) higher levels of both total PA activity and u-PA levels. Linear regression analysis showed a positive correlation (r = .65, P = .007) between total PA activity and u-PA levels. CONCLUSIONS: Squamous cell carcinomas of the head and neck are able to activate plasminogen and produce u-PA in vitro. The production of PA by squamous cell carcinomas of the head and neck may play an important role in the biology of invasion and metastasis.
Assuntos
Carcinoma de Células Escamosas/enzimologia , Neoplasias de Cabeça e Pescoço/enzimologia , Ativadores de Plasminogênio/biossíntese , Ativador de Plasminogênio Tipo Uroquinase/biossíntese , Carcinoma de Células Escamosas/secundário , Humanos , Ativadores de Plasminogênio/metabolismo , Análise de Regressão , Fatores de Tempo , Células Tumorais Cultivadas , Ativador de Plasminogênio Tipo Uroquinase/metabolismoRESUMO
Free tissue transfer of a jejunal segment was undertaken for laryngopharyngoesophageal reconstruction in 20 patients who received postoperative irradiation therapy. Treatment consisted of 1.8- to 2-Gy-fractions, the average total dose was 55.57 Gy (range, 40 to 66 Gy). Anastomotic strictures (six) were encountered early in the series and associated with stapled anastomoses. Hand-sewing the jejunoesophagostomy eliminated the problem. Enteric cutaneous fistula, bowel necrosis, and hemorrhagic enteritis were not observed. We conclude that the application of postoperative irradiation therapy to patients requiring jejunal interposition grafts is feasible.