RESUMO
ADP-ribosylation factor 1 (ARF1) was originally found as a cofactor in CT-catalyzed ADP-ribosylation of Galpha(s) but is now known to participate in vesicle trafficking. We asked whether ARF1 function in vesicular trafficking is necessary for CT-induced morphological changes in Chinese hamster ovary (CHO) cells, which result from increased intracellular cAMP. Brefeldin A treatment of cells suppressed CT action, confirming a requirement for Golgi integrity. Overexpression of a GFP-ARF1 fusion protein did not affect the morphological changes induced by CT, but changes were reduced in cells overexpressing guanine nucleotide exchange-defective ARF1(T31N) or GTP hydrolysis-deficient ARF1(Q71L) mutants. In cells expressing these mutants, 8-bromo-cAMP induced changes similar to those seen in cells transfected with ARF1 or vector. Inhibition of CT action was specific for mutants of ARF1 and not reproduced by analogous mutants of ARF5 or ARF6. ARF1(Q71L) was mostly colocalized with betaCOP, but ARF5(Q71L) less so. ARF6(Q67L) did not colocalize with betaCOP and was partially associated with the plasma membrane. These data are consistent with the conclusion that ARF1 influenced CT action in cells by its specific function in the vesicular transport pathway used by CT to travel from plasma membrane to Golgi to ER.
Assuntos
Fator 1 de Ribosilação do ADP/fisiologia , Toxina da Cólera/farmacologia , Ovário/efeitos dos fármacos , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Animais , Sequência de Bases , Brefeldina A/farmacologia , Células CHO , Cricetinae , Cricetulus , Primers do DNA , Feminino , Ovário/citologia , Transporte ProteicoRESUMO
The prognosis of patients with bladder cancer with pelvic lymph node metastasis is poor, and only 30% of them have been reported to achieve 5- and 10-year survival rates. Prognosis of the patients with pelvic lymph node metastasis larger than 5 cm (N3) is especially poor. and no patient has been reported to have survived more than 3 years. The authors report the successful treatment of two patients with pelvic N3 bladder cancer by internal iliac arterial infusion chemotherapy combined with whole-pelvis irradiation.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/radioterapia , Doxorrubicina/análogos & derivados , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/radioterapia , Idoso , Carboplatina/administração & dosagem , Carcinoma de Células de Transição/patologia , Cisplatino/administração & dosagem , Doxorrubicina/administração & dosagem , Humanos , Artéria Ilíaca , Infusões Intra-Arteriais , Metástase Linfática , Masculino , Metotrexato/administração & dosagem , Estadiamento de Neoplasias , Neoplasias da Bexiga Urinária/patologiaRESUMO
Treatment by internal iliac arterial infusion chemotherapy (IA) combined with pelvic irradiation has proved to be effective for locally invasive bladder. Eight male patients, median age of 78 years (range 73-81) were enrolled. Pretreatment CT and whole layer core biopsy revealed T3a or T3b. Pelvic CT or fine needle aspiration biopsy following bipedal lymphography revealed N0 in 4 cases, N2 in 2 and N3 in 2, respectively. Three to 7 cycles of cisplatin (CDDP) 30-50 mg/m2, methotrexate 20 mg/m2 and tetrahydropymnyl-adriamycin 20 mg/m2 every 3 week was administered combined with 40-50 Gy. of whole pelvis irradiation. In 4 renal function impaired patients, 100 mg/m2 of carboplatin was administered instead of CDDP. All patients obtained complete response and the bladders were preserved. Observation periods were from 9 to 75 months (median 37 months). One N2 patient died with metastatic disease and two died without carcinoma. Two patients developed invasive bladder cancer on the side opposite to the primary tumors. Both were successfully treated by IA and irradiation. Bladders of all except one patient functioned for a long period. Side effects of IA and irradiation were not significant. IA combined with pelvic irradiation is effective and safe for elderly patients with bladder carcinoma.