RESUMO
BACKGROUND: Epidermal growth factor receptor (EGFR) overexpression and prognostic value in head and neck squamous cell cancer is the basis for targeting by anti-EGFR antibodies, which increase the efficacy of radiotherapy. In order to evaluate the best therapeutic schedule, the effects of cetuximab (C225) on Hep-2 cell proliferation, alone and in combination with cisplatin, were studied. METHODS: Hep-2 cells were treated with cetuximab alone or in combination with cisplatin. After determining cell viability with trypan blue, morphological features of apoptotic degeneration were analysed by fluorescence microscopy with Hoechst 33258 stain. RESULTS: Cetuximab alone mildly inhibited Hep-2 proliferation and showed no pro-apoptotic effects. When administered concomitantly with cisplatin, cetuximab synergistically increased inhibition of proliferation and apoptosis. CONCLUSION: The antiproliferative activity of cetuximab is consistent with its hypothesised role in inhibiting repopulation. However, the increase in the effects of pro-apoptotic agents induced by cetuximab may be even more relevant to its clinical effectiveness than the inhibition of repopulation.
Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Receptores ErbB/metabolismo , Neoplasias Laríngeas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cetuximab , Combinação de Medicamentos , Quimioterapia Combinada , Receptores ErbB/antagonistas & inibidores , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
Aim of the present report is to discuss and underline the diagnostic algorithm and the surgical approach to giant parotid pleomorphic adenomas arising in the deep lobe and growing in the parapharyngeal space. Three cases are described and a review is made of the international literature concerning giant deep lobe parotid gland pleomorphic adenoma. Diagnosis was based on imaging, computed tomography scan and magnetic resonance imaging and upon cytology, by means of fine needle aspiration biopsy. The surgical approach varied according to the location of the tumour. All patients were discharged without complications and no cases of permanent facial nerve palsy were observed. An exhaustive pre-operative diagnostic algorithm is required before approaching this lesion. Fine needle aspiration biopsy is, in our opinion, mandatory to avoid histological surprises. The surgical approach should provide excellent visibility with wide surgical exposure to secure local neurovascular structures.
Assuntos
Adenoma Pleomorfo/patologia , Neoplasias Parotídeas/patologia , Adenoma Pleomorfo/cirurgia , Adulto , Humanos , Masculino , Neoplasias Parotídeas/cirurgia , FaringeRESUMO
INTRODUCTION: We present a family comprising a clinically normal mother and two daughters, each with severe encephalopathy with onset in late childhood. A third daughter had died previously of an earlier onset but neuropathologically similar disease. METHODS: Sequence analysis of the entire mtDNA was carried out in muscle, fibroblasts, and lymphocytes of the affected daughters and unaffected mother. Biochemical analysis of individual respiratory chain enzymes was performed on the same tissues, and on several transmitochondrial cybrid clones containing the nucleus of a 143B.206 osteosarcoma cell line and the mutant mtDNA. RESULTS: Genetic analyses revealed in both daughters and mother the presence of a novel mutation in the tRNA(Ile) gene of mtDNA, which was homoplasmic in fibroblasts, lymphocytes, and skeletal muscle of the two patients. It was also homoplasmic in fibroblast and skeletal muscle samples of the mother, and approximately 97% heteroplasmic in her lymphocytes. Combined defects of complexes I and IV of the mitochondrial respiratory chain were found not only in fibroblasts of the two probands, but surprisingly also in those of their clinically unaffected mother. The respiratory chain defect segregated in transmitochondrial cybrids containing the nucleus of a 143B.206 osteosarcoma cell line and the mutant mtDNA, indicating that the latter was responsible for the biochemical phenotype. DISCUSSION: Our results support the concept that homoplasmic mutations in tRNA genes can be responsible for mitochondrial disorders characterised by extremely variable penetrance. Albeit still unexplained, this phenomenon has important consequences in the nosological characterisation, clinical management, and genetic counselling of mitochondrial disorders.