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1.
BACKGROUND: Angiogenesis is an essential process required for growth and metastasis in cancer. In breast, gastric, and prostate cancer, vascular endothelial growth factor (VEGF) has been implicated in angiogenesis; however, little is known about VEGF in HNSCC. In this study, we hypothesize that VEGF is present in elevated levels in HNSCC and may therefore play a role in promoting angiogenesis. METHODS: We obtained tumor tissue from 63 HNSCC patients undergoing primary resection. All tissue samples were analyzed by immunohistochemistry (IHC) techniques for the presence and localization of VEGF; however, only 36 had sufficient amounts of tissue for quantitative analysis of VEGF by ELISA. Nine control specimens taken from patients undergoing uvulopalatopharyngoplasty were also analyzed. RESULTS: In all 63 of our patient samples we found VEGF to be present and localized to the cancer cells and endothelial cells. The poorly differentiated cancer cells stained more intensely in comparison with the well-differentiated ones. There was a 20-fold increase in the patient levels when compared with controls levels (P > or =0.05). Analysis by enzyme-linked immunosorbent assay revealed elevated mean levels of VEGF (241 +/- 326 pg/mg total protein [TP]) with a range of 2 to 1484 pg/mg TP. The control specimens had mean levels of 13 +/- 11 pg/mg TP and a range of 1 to 78 pg/mg TP. Patients who exhibited higher levels of VEGF tended to have a higher rate of disease recurrence (P < or =0.048) and shorter disease-free interval (P < or =0.05). CONCLUSIONS: The expression of VEGF in elevated levels in the HNSCC tumor microenvironment appears to be associated with more aggressive disease. Based on our results, VEGF may be an important angiogenic factor associated with cancer cells and endothelial cells in HNSCC. Further studies are needed to better define the role of VEGF in HNSCC and its role as a potential target for therapeutic intervention.  相似文献   

2.
Local invasion and lymph node metastasis are correlated with a decreased overall survival in head and neck cancer patients and warrant new strategies to intervene in the metastatic cascade. One approach is to focus on the intracellular signaling pathways underlying the metastatic process. A common regulatory point in several signal transduction pathways is intracellular calcium homeostasis. We assessed the effect of a novel calcium influx inhibitor, carboxyamido-triazole (CAI), on the growth and invasive phenotype of cell lines derived from head and neck squamous cell carcinoma (HNSCC). CAI inhibited the growth of FaDu and EVSCC17M cells in a dose-dependent (IC50, 13-15 microM) and reversible manner. CAI also caused a generalized attenuation of receptor-mediated calcium elevation to several calcium mobilization agonists, including epidermal growth factor and bradykinin. The effects of CAI on the invasive phenotype of HNSCC cell lines were assessed by a chemo-invasion assay. HNSCC cell lines exhibited a range of invasive potential as measured by the capacity of tumor cells to penetrate a reconstituted basement membrane of Matrigel. HNSCCs were classified as highly invasive (EVSCC14M and EVSCC17M) or weakly invasive (EVSCC18, EVSCC19M, UMSCC10A, and FaDu). Treatment of HNSCC cell lines with 10 microM CAI for 24 h reduced invasion 2-14-fold in a dose-dependent manner. HNSCCs also exhibited different motilities as measured by a chemotaxis assay. EVSCC14M and EVSCC17M were highly motile, whereas EVSCC18, EVSCC19M, UMSCC10A, and FaDu were less motile. CAI reduced the migration of all cell lines. Conditioned medium from HNSCC cell lines was analyzed by zymography for production of Mr 72,000 type IV collagenase [matrix metalloproteinase (MMP)-2)] and Mr 92,000 type IV collagenase (MMP-9). All HNSCC cell lines secreted MMP-2 and/or MMP-9 into conditioned medium. Treatment of cells with 10 microM CAI for 24 h resulted in a reduction of both MMP-2 and MMP-9 production. The results demonstrate that CAI blocks cellular proliferation, migration, chemoinvasion, and MMP production by HNSCC in vitro and identify calcium-dependent signaling as a new target for inhibition of the malignant phenotype of HNSCC.  相似文献   

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BACKGROUND: Mutation of the p53 tumor suppressor gene (also known as TP53) often leads to the synthesis of p53 protein that has a longer than normal half-life. Mutant p53 protein that accumulates in tumor cell nuclei can be detected by means of immunohistochemical staining techniques. Serum antibodies directed against p53 protein (p53-Abs) have been detected in some cancer patients. PURPOSE: We assayed serum samples from 80 patients with head and neck squamous cell carcinoma (HNSCC) for the presence of p53-Abs, and we evaluated potential associations between the presence of these antibodies and other histopathologic and clinical features. METHODS: Serum was collected from each patient at the time of diagnosis. In addition, tumor biopsy specimens were obtained before the initiation of treatment. An enzyme-linked immunosorbent assay was used to detect p53-Abs. The accumulation of p53 protein in tumor cell nuclei was assessed immunohistochemically by use of the anti-p53 monoclonal antibody DO7. Patient treatment consisted of radiotherapy alone, primary chemotherapy followed by radiotherapy, or surgery and postoperative radiotherapy. Relapse-free and overall survival from the beginning of treatment were estimated by use of the Kaplan-Meier method; survival comparisons were made by use of the logrank statistic. Univariate and multivariate analyses were conducted to identify factors associated with survival. Reported P values are two-sided. RESULTS: Fifteen (18.8%) of the 80 patients had p53-Abs. Tumor cell nuclei in 43 (58.9%) of 73 assessable biopsy specimens exhibited strong p53 immunostaining. Patient treatment method and the accumulation of p53 protein in tumor cell nuclei were not associated with increased risks of relapse or death. In univariate analyses, advanced tumor stage (> T1 [TNM classification]) and the presence of p53-Abs were significantly associated with an increased risk of death (P for trend = .007 and P = .002, respectively), whereas advanced tumor stage, substantial regional lymph node involvement (> N1), and the presence of p53-Abs were associated with an increased risk of relapse (P for trend = .002, P = .02, and P < .0001, respectively). In multivariate analyses, advanced tumor stage and the presence of p53-Abs were significantly associated with increased risks of relapse (p for trend = .04 and P = .003, respectively) and death (P for trend = .04 and P = .03, respectively). At 2 years of follow-up, the overall survival proportion was 63% (95% confidence interval [CI] = 47%-80%) when no p53-Abs were detected compared with 29% (95% CI = 4%-54%) when p53-Abs were detected. Relapse-free survival at 2 years was 62% (95% CI = 49%-76%) if no p53-Abs were detected compared with 13% (95% CI = 0%-31%) if p53-Abs were detected. CONCLUSIONS AND IMPLICATIONS: The proportion of patients with HNSCC who have serum p53-Abs is smaller than that of patients exhibiting tumor cell accumulation of p53 protein. The presence of p53-Abs is significantly associated with increased risks of relapse and death.  相似文献   

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Ionizing radiation (XRT) is often used to treat squamous cell carcinoma of the tongue (SCCT) but little is known of its genetic effects on surviving cancer cells. The effect of XRT on p53, epidermal growth factor receptor (EGFR), and transforming growth factor alpha (TGF alpha) tumor marker expression was evaluated using immunohistochemical analysis in 79 patients with SCCT. Sixty-six patients received no radiation, while 13 received XRT before surgery. Radiation did not influence EGFR or p53 expression. TGF alpha expression, however, was significantly decreased in radiated tumors (15% versus 43%, P = 0.04). These data suggest that XRT either decreases the expression of TGF alpha in SCCT (suggesting a genetic alteration in surviving cancer cells), or does not kill cancer cells with decreased TGF alpha expression. In the latter case, diminished TGF alpha expression may serve as a marker of radioresistance.  相似文献   

6.
A continuous fluorometric assay for tryptophan hydroxylase activity based on the different spectral characteristics of tryptophan and 5-hydroxytryptophan is presented. Hydroxylation of tryptophan at the 5-position results in a large increase in the fluorescence of the molecule. The assay selectively monitors the fluorescence yield of 5-hydroxytryptophan by exciting the reaction mix at 300 nm. The rate of increase of the emission signal was found to be directly proportional to the enzyme concentration. Inner filter effects due to quinonoid dihydropterin accumulation were eliminated by the inclusion of a thiol reductant. Activity measured using this assay method was found to be the same as that determined by established discontinuous HPLC assay methods. The application of the assay to routine activity measurements and to steady-state determinations with the substrates tryptophan and tetrahydropterin is described.  相似文献   

7.
Two experiments were conducted to study the effect(s) of Borrelia burgdorferi and its metabolites (toxicants?) on canine spermatozoa, using B burgdorferi type strain B-31 and ejaculates from 5 sexually mature dogs. In Experiment 1 the spirochetes were cocultured with semen and incubated under various conditions, and in Experiment 2 the spirochetes were sonicated to release the metabolites/toxicants. The sonicate was then cultured with the semen. The parameters investigated were kinematics and percentage of sperm motility, morphology, and sperm response to the hypoosmotic swelling test and acrosome reaction. There were no visible physical interaction between either dead or motile spirochetes and viable or dead spermatozoa. Neither the spirochetes per se nor their metabolites/toxicants had any significant adverse effect on the functional and morphological characteristics of the canine spermatozoa. It is possible that the exposure times for incubation were not long enough for metabolites or toxicants in the sonicate to significantly affect sperm characteristics. Some investigators have reported that B burgdorferi contain biologically active LPS-like endotoxins. It is also likely that storage denatures B burgdorferi metabolites and other intracellular products in the sonicate and, thus, negates any effects the medium or the sonicate might have on the spermatozoa. The apparent lack of effect suggests that either peripheral metabolism or action on other organ(s) may be required for deleterious action of the spirochetes and/or their toxicants on spermatozoa. It was concluded that B burgdorferi and/or metabolites/toxicants do not have any significant deleterious effects on the functional and morphological characteristics of the postspermatogenic spermatozoa. Interaction of the spirochetes with in vivo conditions may be needed to adversely affect spermatozoa.  相似文献   

8.
In the present study, we analyzed 28 squamous cell carcinomas of the head and neck (SCCHN) for mutations in the coding region of TbetaR-II using 'Cold' SSCP and automatic DNA sequencing analyses. Twenty-one percent (6/28) of the SCCHN examined contained TbetaR-II mutations compared with patient-matched normal tissues. These alterations included five missense mutations (A:T-->G:C transitions in codons 250, 401, 448 and 488, and a G:C-->T:A transversion in codon 373), and a 38-bp deletion between nucleotides 1825 to 1862. In addition to these code-altering mutations, one case exhibited a silent mutation (A:T-->G:C transition in codon 451) and three cases contained one of two potential population polymorphisms (codons 354 and 389). In contrast to colon and gastric cancers exhibiting microsatellite instability (MI) or replication errors (RER+), no 'indirect' frameshift mutations were identified within a 10-bp polyadenine repeat present in the TbetaR-II coding sequence. All of the mutations in the present study occurred within the highly conserved serine/threonine kinase domain and represent the first report of such 'direct' TbetaR-II mutations in primary human tumors. In addition, we analyzed a subset of SCCHN and corresponding normal samples for TbetaR-II mRNA expression using semi-quantitative multiplex RT-PCR. Expression of TbetaR-II was decreased by 24% to 74% in 20 of 23 SCCHN (87%) compared with patient-matched normal tissues. Taken together, the results from this study suggest that alterations in the nucleic acid sequence and mRNA expression of TbetaR-II are prevalent events in the development of SCCHN, which may deregulate cell cycle control.  相似文献   

9.
Genomic instability or microsatellite instability (MI) in simple repeated sequences was initially recognised in colonic carcinomas and subsequently in other tumours. MI has been associated with mutations in genes concerned with replication and DNA repair. We investigated 34 microsatellite markers in squamous cell carcinoma of the head and neck (SCCHN). Fifty-six tumours, were studied, of which 25 were investigated with ten or more microsatellite markers. In this study we consider two or more microsatellite alterations in a tumour to be diagnostic of MI. We demonstrated that 7/25 (28%) of the tumours had MI at two or more loci and three of these tumours exhibited evidence of 20 or more loci with MI. No correlations were found between MI and previous treatment, site, histological differentiation, positive nodes at pathology, a history of alcohol intake or survival. MI has been demonstrated in T1N0 stage tumours, indicating that these changes may occur early in the disease process. A negative correlation was found between MI and a history of smoking (P = 0.02). Two or more markers of MI were found in three of four non-smokers compared with one of 13 in the smoking group of patients, which suggests a novel mechanism of carcinogenesis in non-smokers.  相似文献   

10.
BACKGROUND: Galectins are carbohydrate-binding proteins thought to be important for cell growth and differentiation, whose expression is altered in some tumors with aggressive phenotype. Our objective was to evaluate the expression of galectins in head and neck squamous cell carcinoma (HNSCC). METHODS: Fourteen HNSCC cell lines and four primary tumor specimens were evaluated using immunoblotting, and immunohistochemical analysis was performed on 35 primary HNSCCs. RESULTS: Galectin-1 and galectin-3 were expressed in most HNSCC cell lines and primary tumor specimens. Galectin-1 was detected in the basal layer of normal adjacent mucosa, in connective tissue stroma, and at the periphery of invasive tumor islands. Galectin-3 localized to superficial mucosal layers, and adjacent to keratin pearls in invasive carcinoma. CONCLUSIONS: Galectins are manifested in HNSCC tumors and are localized to the cell surface, where they may participate in cellular interactions. The expression pattern of galectins appears to be associated with degree of squamous differentiation, suggesting a potential role for galectins as biologic and differentiation markers in HNSCC.  相似文献   

11.
Head and neck squamous cell carcinoma (HNSCC) is an aggressive malignancy in which multiple independent lesions develop over time throughout the mucosa of the upper aerodigestive tract. Therefore, the comprehensive treatment of this neoplasm must include a chemopreventive arm to hold premalignant lesions in check, a role well-suited to antiangiogenic agents. Retinoic acid (RA) and interferon alpha (IFN-alpha), drugs with known biological activity against HNSCC when used individually, are also inhibitors of angiogenesis. Here we show that they are remarkably synergistic antiangiogenic agents able to inhibit both the growth and the neovascularization of HNSCC injected into the floor of the mouth of nude mice. The mechanism of action of these drugs as antiangiogenic agents was 2-fold. They decreased the angiogenic activity of the tumor cells, and they caused the endothelial cells to become refractory to inducers of angiogenesis. When tumor cells were treated in vitro with IFN-alpha A/D, there was a dramatic drop in their secretion of interleukin-8, the major angiogenic factor produced by these tumors. When combined with RA, which causes tumor cells to secrete an inhibitor of angiogenesis, there was a synergistic inhibition of both tumor cell growth and secreted angiogenic activity. The combination of RA and IFN-alpha also acted synergistically on endothelial cells by reducing their responsiveness to both interleukin-8 and tumor conditioned media. Doses of each drug could be reduced by two logs without loss of activity. When animals bearing human HNSCC tumor cells were treated systemically with a combination of RA and IFN-alpha A/D at doses that were ineffective when used alone, dramatic decreases in both tumor growth and tumor angiogenesis were seen. These data suggest that the use of antiangiogenic mixtures may be a particularly effective way to design future chemoprevention protocols against HNSCC.  相似文献   

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The relation between 21 absolute body dimensions as well as 20 anthropometric indices and the length as well as the regularity of the menstrual cycle have been investigated in 156 patients of the hormone ambulance of the I. Universit?ts-Frauenklinik in Vienna. It turned out, that the length as well as the regularity of the menstrual cycle significantly negatively with the amount of the subcutaneous fat tissue. With an increasing amount of adipose tissue, the cycle became shorter and more regular. The importance of the subcutaneous fat tissue as a secondary hormonal gland has been discussed as one cause for these significant connections. Regarding the length- and height dimensions and the menstrual cycle patterns, no statistically significantly relationship could be observed between these two trait system. This is also true for the relationship between body built and the bleeding duration.  相似文献   

14.
The predominant extracranial head and neck cancer in adults is squamous cell carcinoma. The purpose of this article is to discuss the radiographic evaluation of these patients with computed tomography (CT) or magnetic resonance (MR) imaging prior to therapeutic intervention. Specific focus is given to the efficacy of CT and MR imaging, as an adjunct to clinical staging, for evaluation of the primary tumor, and metastatic adenopathy. MR imaging, because of its improved soft tissue contrast and multiplanar capability, is probably superior to CT for evaluation of the primary tumor in patients with squamous cell carcinoma. CT, however, remains the gold standard for identifying metastatic adenopathy and in most institutions remains the study of choice for evaluating this patient population.  相似文献   

15.
A potent neutralizing monoclonal antibody to the human alpha platelet-derived growth factor (PDGF) receptor (alpha PDGFR) was raised by immunizing BALB/c mice with 32D cells expressing the human alpha PDGFR. This monoclonal antibody, designated alpha R1, immunoprecipitated human, monkey, rabbit, pig, dog, and cat, but not hamster, rat, or mouse alpha PDGFRs. Comparison with PR292, a monoclonal antibody previously generated against the alpha PDGFR, showed that both recognized alpha PDGFR extracellular domains, but neither demonstrated reactivity against the beta PDGFR. In vitro binding studies revealed that alpha R1, but not PR292, detection of the alpha PDGFR was blocked by either PDGF AA or PDGF BB. These results strongly suggest that the receptor ligand-binding domain spatially overlapped with the alpha R1 epitope. Monoclonal antibody alpha R1 also inhibited PDGF stimulation of [3H]thymidine uptake by 32D cells expressing the alpha PDGFR (32D alpha R) as well as autocrine growth stimulation of 32D alpha R cells transfected with and expressing PDGF AA or PDGF BB. Therefore, monoclonal antibody alpha R1 may be useful in the detection and growth inhibition of malignancies in which PDGF autocrine stimulation and/or alpha PDGFR overexpression plays an important role(s).  相似文献   

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BACKGROUND: Squamous cell carcinomas of the head and neck (SCCHN), unlike normal mucosal squamous epithelial cells, overexpress epidermal growth factor receptor (EGFR) messenger RNA and protein. EGFR protein is required to sustain the proliferation of SCCHN cells in vitro. To determine whether EGFR expression contributes to tumor growth, we investigated the effect of suppressing EGFR expression in tumor xenografts through in situ expression of antisense oligonucleotides. METHODS: Intratumoral cationic liposome-mediated gene transfer was used to deliver plasmids capable of expressing sense or antisense EGFR sequences into human head and neck tumors, which were grown as subcutaneous xenografts in nude mice. The oligonucleotides were expressed under the control of the U6 RNA promoter. RESULTS: Direct inoculation of the EGFR antisense (but not the corresponding sense) plasmid construct into established SCCHN xenografts resulted in inhibition of tumor growth, suppression of EGFR protein expression, and an increased rate of apoptosis (programmed cell death). Sustained antitumor effects were observed for up to 2 weeks after the treatments were discontinued. CONCLUSION: These results suggest that interference with EGFR expression, using an antisense-based gene therapy approach, may be an effective means of treating EGFR-overexpressing tumors, including SCCHN.  相似文献   

19.
Papillary renal carcinomas are a cytogenetically unique subset of renal carcinomas that have been reported to be clinically less aggressive. We have examined 19 papillary tumors for immunohistochemical expression of the epidermal growth factor receptor (EGF-R) and its ligand, transforming growth factor alpha (TGF-alpha). EGF-R and TGF-alpha expression was also studied in 149 nonpapillary tumors and 7 mixed papillary/solid tumors. EGF-R and TGF-alpha expression were compared to histology, stage, metastatic behavior, and survival. Formalin-fixed, paraffin-embedded nephrectomy specimens collected between 1977 and 1986 were stained with antibodies to EGF-R and TGF-alpha. Patients with papillary tumors were found to present with earlier stage disease and had significantly longer survival. Papillary tumors had a significantly lower rate of EGF-R positivity than solid pattern tumors (21% versus 73%, P < 0.001). Intermediate or strong cell membrane immunoreactivity for EGF-R was associated with high tumor grade and poor disease-specific survival. EGF-R positivity in the primary tumor was associated with the presence of metastatic disease and with metastatic spread to lung versus bone. Tumor parenchymal TGF-alpha staining was present in 50% of the cases and was not associated with stage or grade. Unrelated to tumor parenchymal TGF staining, tumor vessels stained for TGF-alpha in 56% of the cases. Vessel TGF-alpha staining was absent in papillary tumors (P < 0.001). The improved clinical behavior of papillary tumors as compared to nonpapillary renal tumors may be related, in part, to their relatively lower levels of EGF-R expression.  相似文献   

20.
We describe multiple cutaneous squamous cell carcinomas of the head and neck in five patients with chronic lymphocytic leukaemia (CLL). When associated with CLL, cutaneous squamous cell carcinomata behave in a much more aggressive manner than otherwise expected. Four patients developed local recurrence after primary treatment. All five patients developed lymph node metastases containing squamous cell carcinoma. Three of five patients (60 per cent) had multiple primary lesions. Whereas the increased incidence of second cancers in CLL and notably of skin cancers is documented, little has been written to describe the aggressive behaviour of these tumours. It is important, when treating these patients, to be aware of the high tendency towards local recurrence and lymph node metastasis and to consider an aggressive management plan and careful follow-up.  相似文献   

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