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Inclusion of chemotherapeutic drugs in treatment of patients with newly diagnosed head and neck cancer has improved response rates and prolonged median survival. Nevertheless, most patients with advanced head and neck cancer are destined to relapse and to develop resistance to initially used drugs such as paclitaxel. Consequently, it has been more important in cancer therapy to determine the molecular mechanisms that are related to cell-killing effects of anti-cancer agents or cancer resistance against them. Consequently, we examined whether abrogation of histone deacetylase 3 (HDAC3) expression by anti-sense oligonucleotides (ASOs) potentiates the efficacy of paclitaxel in human maxillary cancer IMC-3 cells. Here, we showed that paclitaxel-induced apoptosis was enhanced significantly by addition of ASOs for HDAC3 in cultured cells. Furthermore, paclitaxel-induced apoptosis in IMC-3 tumors transplanted in nude mice was enhanced significantly by administration of ASOs for HDAC3, thereby suppressing tumor growth. We provide new evidence that HDAC3 is a novel molecular target whose inactivation can potentiate the efficacy of anti-cancer drugs disrupting microtubules such as paclitaxel., (Copyright (c) 2010 Elsevier Inc. All rights reserved.)

Objective: To detect the expression of a disintegrin-like and metalloproteinase (ADAM) 8 and 12 gene in the giant cell lesions of jaw and to study their effects on the histogenesis of cells in these lesions., Methods: ADAM8 and ADAM12 was detected by immunohistochemistry (SP) in 40 paraffin-embedded specimens of central giant cell lesions of jaw, 10 peripheral giant cell lesions, 9 cherubisms, 6 aneurysmal bone cysts., Results: ADAM8 and ADAM12 were positive in the cytomembrane and cytoplasm of all multinucleated giant cells and some round mononuclear cells of the lesions; ADAM12 was positive for some spindle mononuclear stromal cells in central and peripheral giant cell lesions., Conclusions: Multinucleated giant cells probably originated from the fusion of the round mononuclear cells, and ADAM8 and ADAM12 were involved in this process. In addition, ADAM12 might play a role in the maturation of spindle mononuclear stromal cells.

Considering the influence on the molecular level of the neoplasic factors, upon several proteins, nucleic acids, one can say that some of the oncogenesis determinants are represented by genetic mutations. Free radicals, including also some organic peroxides are considered as tumour promoters, although the exact mechanism of this process in still unknown. The neoplasic disease is characterized generally by disorders of the control processes, including the one displayed on the subcellular level. Considering the enzymatic changes occurred in erythrocytes and determined by the disturbances of membrane permeability, we evaluated the response of several aggressions at the erythrocyte level, in case of maxillo-facial tumours. Our results show increase of the LDH, G-6-P-DH activity and decrease of catalase activity within the erythrocyte.

Ten cases of giant cell tumor of maxilla are reported, the patients being children or young adults and of principally female sex. In three cases another affection was associated: Recklinghausen's disease, Francescatti syndrome and hyperthyroidism of adenomatous origin. Histology of all tumors was similar: giant cells, fibroblastic tissue and numerous vessels: the course was benign in all cases with frequent recurrences but no metastases. The pathology of these tumors is still the subject of wide debate, although research is extensive in this field: electron microscopy, histoenzymology, monoclonal antibodies are some aspects studied but results have sofar failed to elucidate the true nature and histoprognosis of these tumors.

Cathepsin B and collagenolytic cathepsin activities were studied biochemically in human aqueous humor. The enzyme activities were found to be significantly high in the aqueous humor of the patients with Behçet's disease, but not detectable in those with senile cataract, retinoblastoma, and maxillar carcinoma. These data suggest that cathepsin B and collagenolytic cathepsin have a certain role in the inflammatory collagenolytic process of Behçet's disease.

A case of osteogenic sarcoma of the maxilla is described. The tumor was excised by a hemimaxillectomy but recurred in 3 months. The patient died 8 months after the initial onset of symptoms. Chemotherapy and radiation were ineffective with the exception of bleomycin, which caused necrosis of the tumour, with no apparent increase in growth, and a decrease of the serum alkaline phosphatase level to less than half of the maximum value. There was a close correlation between the fluctuating pattern of the serum alkaline phosphatase level and the growth and remission of the tumour during the entire course of treatment.

A cell line, designated OKK, has been established from a human maxillary carcinoma in a Japanese man. The cultured cells were inoculated into nude mice, with the subsequent establishment of tumors. Alkaline phosphatases were extracted from these tumors and partially purified by chromatography. The electrophoretically fastest moving isoenzyme, designated tentatively as OKK T isoenzyme, was biochemically and immunologically investigated by comparing it with the Kasahara isoenzyme purified partially from the tumor, which originated from FL cells inoculated into a nude mouse. The properties of the OKK T isoenzyme were identical to those of the Kasahara isoenzyme. Thus, the enzymes showed a similar inhibition by amino acids (L-phenylalanine and L-leucine), the same behavior with respect to other properties, including heat stability, immunological character and molecular weight. The genetic phenotype of the glucose-6-phosphate dehydrogenase of this established cell line was proved not to be identical to that of a HeLa cell line.

The Kasahara isoenzyme of alkaline phosphatase was found in cancer tissues from patients with gastric carcinoma, maxillary carcinoma, pulmonary carcinoma, and carcinoma of the urinary bladder, in addition to hepatoma. This fact suggests that the Kasahara isoenzyme may not be a specific marker protein of liver cancer but could occur in a variety of neoplasms.

A case of fibrosarcoma of the maxilla with strong alkaline phosphatase activity in the tumor cells is described, and the significance of this enzyme is discussed.