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141.
O-charoenrat P Rhys-Evans P Court WJ Box GM Eccles SA 《Clinical & experimental metastasis》1999,17(7):631-639
Evidence suggests that there is an association between the abnormal expression of members of the c-erbB receptor tyrosine kinase family and poor prognosis in head and neck squamous cell carcinomas (HNSCC). Until now, the relative
contributions of different c-erbB ligands to HNSCC progression have not been clearly defined. In this paper we examined the effects of ligands with different
c-erbB receptor specificities in terms of their stimulation of HNSCC proliferation, expression of matrix metalloproteinases (MMPs)
and invasion. Heregulin-beta1 (HRG-β1; selective c-erbB3/B4 ligand) was found to stimulate proliferation in the majority of cell lines, whereas epidermal growth factor (EGF; EGFR
ligand) and betacellulin (BTC; EGFR/B4 ligand) induced variable responses. All three ligands up-regulated multiple MMPs including
collagenases, stromelysins, matrilysin and gelatinase B (MMP-9) but had minimal or no effects on gelatinase A (MMP-2), MT1-MMP
and tissue inhibitors of MMPs (TIMPs). MMP-9 mRNA was induced to a higher level than other MMPs, although with slower kinetics.
HRG-β1 was less active than EGF and BTC at the optimal concentration (relative potency of EGF:BTC:HRG = 3:4:1). In vitro invasion through Matrigel was also increased by all three ligands in proportion to their MMP up-regulation. A specific anti-EGFR
monoclonal antibody (mAb ICR62) inhibited MMP up-regulation, migration and invasion induced by all three ligands, whereas
an anti-c-erbB-2 mAb ICR12 inhibited mitogenic and motogenic responses following ligand stimulation but had no effect on MMP expression.
These results suggest that c-erbB ligands may differentially potentiate the invasive phenotype of HNSCC via co-operative induction of cell proliferation,
migration and proteolysis. The EGFR signalling pathway appears to be the dominant component controlling the proteolytic and
invasive phenotype in HNSCC, whereas the c-erbB-2 signalling pathway is responsible, in part, for the mitogenic and motogenic effects of ligands.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
142.
It has been shown previously that the antero-inferior cortex is subjected to maximal tensile stress during a fall onto the
greater trochanter. We have recently shown that in cases of femoral neck fracture, cortical thinning and porosity is greatest
in the anterior and antero-inferior region of the femoral neck. To investigate whether this is due to increased remodeling,
we have quantified surface-based parameters associated with Haversian remodeling in femoral neck biopsies from women with
intracapsular hip fracture and post-mortem controls. Cryostat sections of chilled biopsies were reacted for either tartrate-resistant
acid phosphatase (TRAP) or alkaline phosphatase (ALP) activity. Proportions of active canals were determined in each quadrant
(inferior, anterior, superior, posterior) of the femoral neck. The biopsies were then embedded in methacrylate to permit histomorphometry
using Goldner’s and Solochrome sections. In the cases there was no significant increase in the proportion of canals undergoing
remodeling in the cortex as a whole (p = 0.846), but the regional distribution of remodeling was markedly different from that in the controls. In the anterior cortex,
the proportion of canals undergoing remodeling was increased by 56% (p = 0.0087); in contrast there was a relative decrease of 35% in the superior region (p = 0.0047). In the anterior cortex of cases there were 76% and 42% increases in the proportions of eroded (p = 0.019) and osteoid-bearing (p = 0.041) canals, respectively. In the superior region, the decrease in the proportion of remodeling sites was due to a marked
decrease in canals with an osteoid surface (51%; p = 0.0031). Covariance analysis with cortical porosity as the dependent variable showed that porosity was significantly dependent
on the regional distribution of eroded (p = 0.033) but not on the distribution of forming (p = 0.153) canals (R
2adj = 0.51). Cellular levels of TRAP and ALP were significantly elevated in the anterior region of cases compared with the
controls (TRAP 55%, p = 0.006; ALP 36%, p = 0.003). For the posterior and inferior regions there were no marked differences in cellular TRAP and ALP levels compared
with control values. These data show that the increased cortical thinning and increased porosity we have previously observed
in the anterior cortex in cases of hip fracture are associated with increased indices of Haversian remodeling. These findings
are consistent with the hypothesis that, in cases of hip fracture, remodeling imbalance in the anterior cortex is a continuing
process up to the time of fracture and is due to increased osteoclastic cellular activity associated with an osteoblastic
response that is inadequate to prevent bone loss.
Received: 16 November 1998 / Accepted: 17 February 1999 相似文献
143.
Hayashi Takaharu; Sagawa Hiroshi; Kobuke Kyoko; Fujii Kiyomu; Yokozaki Hiroshi; Tahara Eiichi 《Japanese journal of clinical oncology》1996,26(5):368-373
A case of synchronous squamous cell carcinomas in the soft palate,larynx and esophagus is reported, along with findings of molecular-pathologicalanalysis. A biopsy sample from the aryngeal carcinoma revealedwell differentiated squamous cell carcinoma harboring two pointmutations at codons 144 and 148 of the p53 gene but not at codon299, and more than 50% of the cancer cells showed accumulationof p53 protein immunohistochemically. The esophageal tumor,which was moderately differentiated squamous cell carcinoma,showed immunoreactivity for p53 within the nuclei of 2550%of cancer cells with a missense mutation at codon 299 but notat codon 144 or 148. This cancer also showed immunoreactivityfor transforming growth factor alpha. On the other hand, thepoorly differentiated squamous cell carcinoma in the soft palateshowed negative immunoreactivity for p53 and no point mutationin exons 5 to 8 of the gene. These results suggest that thethree synchronous squamous cell carcinomas arose as independentevents. 相似文献
144.
Piffkó J Bánkfalvi Á Öfner D Tötsch M Berens A Joos U Böcker W Schmid KW 《Pathology oncology research : POR》1996,2(1-2):37-42
Formalin fixed and paraffin embedded samples from 36 squamous cell carcinomas of the larynx and the oral cavity (pT2N0M0, R0) surrounded by non-tumorous mucosa were studied immunohistochemically using a panel of four different anti-p53 antibodies
(CM1, PAbl801, D07, PAb240), a monoclonal anti-mdm2 antibody and MIB1, following wet autoclave antigen retrieval. P53 immunoreactivity
was detected in 11/14 laryngeal and in 9/22 oral carcinomas. All p53 positive oral, and all but one laryngeal tumors revealed
mdm2 positivity as well, whereas in p53 negative tumors 4/12 and 1/3 mdm2 immunopositive cases were demonstrated, respectively.
MIB1 labeling indices of the tumors ranged between 18% – 64% in p53 positive cases, and 10% – 53% in p53 negative ones. The
difference was not statistically significant. Close spatial coexpression of p53, mdm2 and MIB1 immunoreactivity was observed
at the invasive front of the carcinomas and in the basal and suprabasal layers of the non-tumorous epithelium in all p53 positive
cases. However, the MIB1 expression was similarly increased at the invasive margins in carcinomas lacking immunohistochemically
detectable p53 alterations. Our results strongly suggest that p53 overexpression does not necessarily correspond to increased
rate of proliferation, but rather to mdm2 overexpression and is largely dependent on the anatomical site in case of small
and localized squamous cell carcinomas of the head and neck region. 相似文献
145.
McDonald JS Gartside PS Pavelic LJ Gluckman JL Pavelic ZP 《Pathology oncology research : POR》1996,2(1-2):34-36
Archival material from 47 patients with primary squamous cell carcinoma of the head and neck (SCCHN) was studied immunohistochemically
for the presence of nm23-H1 protein. Our data indicate that nm23-H1 protein expression is a common event in SCCHN and that
there is a trend toward correlation of increased expression of nm23-H1 with increasing tumor size (p = 0.072). The results
also show that when adjusting for age and cause of death, there tended to be an inverse relationship between overall survival
and the expression of nm23-H1 gene in the primary tumor (p = 0.088). 相似文献
146.
Thomas Lee Pope Jr. M.D. Theodore E. Keats M.D. Carol B. Stelling M.D. Richard Goldner M.D. Mark Logan M.D. 《Skeletal radiology》1981,7(2):129-130
We have seen two cases of traumatic subcapital fractures of the femoral neck which resembled pathologic fractures on plain radiography. We have named this entity pseudopathologic fracture of the femoral neck and offer suggestions for why it occurs. 相似文献
147.
Dong M. Shin Alan M. Kramer Isaiah W. Dimery Martin N. Raber Michael Ewer Waun Ki Hong 《Investigational new drugs》1991,9(1):89-91
Summary Fourteen patients previously treated with surgery, radiotherapy, and/or chemotherapy for primary squamous cell carcinoma of the head and neck were treated with 4-O-tetrahydropyranyl-Adriamycin (THP-adriamycin) for locally or distantly recurrent disease. The starting dose was 60 mg/m2 by i.v. infusion, with courses repeated every 3 to 4 weeks. A total of 34 courses of treatment were delivered (median, 2; range, 1–6). All patients were evaluable for response and toxicity. There were no responses. Severe (grade 3 or 4) neutropenia occurred in 11 patients. Thrombocytopenia, anemia, and gastrointestinal toxicity were modest, and no hepatic, renal, or cardiac toxicity was observed. The lack of response in association with severe neutropenia and moderate other toxicities using this dose and schedule of THP-Adriamycin should be taken into consideration prior to the pursuit of further study of this compound in a similar patient population. 相似文献
148.
Embolization with “Ethibloc” of vascular tumors and arteriovenous malformations in the head and neck
Summary Ethibloc has been used almost exclusively until now for embolization of tumors and bleeding vessels in the liver and kidney. Unlike with Gelfoam-particles, there is no recanalization. The resorption occurs so slowly that there is no interference with the necrosis of the embolized tumor. Due to its low viscosity, it passes catheters with thin lumina and fills the capillary bed of the tumor without danger of reaching the venous vessels. In this paper we describe a new technic of percutaneous catheter-embolization with Ethibloc using a coaxial catheter which we believe enhances safety and effectiveness. It has been successfully used in five patients. In the meantime two more patients have been treated successfully.Presented in part at the 17th Annual Meeting of the German Society of Neuroradiology, 9–10 October 1981 in Tübingen, FRG. 相似文献
149.
150.
头颈部放射治疗对味觉的损害 总被引:1,自引:0,他引:1
放射线治疗是恶性肿瘤的常用治疗手段之一。头颈部放射治疗常引起局部疼痛、口干、味觉障碍等一系列并发症,可不同程度地影响到病人的生活质量以及对治疗的耐受性。近年来,对头颈部放射治疗并发症的研究已引起临床重视。灵敏的味觉是维持良好生活质量的重要条件之一。味觉障碍既是一种客观症状,也是一种主观感受,它不仅直接抑制病人的食欲,导致营养缺失,更可加重其身心负担。本文对头颈部放疗引起味觉损害的相关研究作一综述,侧重介绍味觉损害的发生机制、临床表现、治疗及预防等方面的新进展。 相似文献