Showing papers by "Sven Saussez published in 2009"

Bisphosphonate-related osteonecrosis of the jaw and its associated risk factors: a Belgian case series.

Abstract: Lesions smaller than 1 cm and lesions that were subject to medical treatments are associated with a better outcome. Surgical treatments appear to be non-beneficial for BROJ.

Galectin-8 up-regulation during hypopharyngeal and laryngeal tumor progression and comparison with galectin-1, -3 and -7.

Abstract: Aim: To define specific staining patterns for the adhesion/growth-regulatory lectin tandem-repeat-type galectin-8 in hypopharyngeal and laryngeal tumor progression and relate these parameters to galectins 1, 3 and 7 in the quest to explore the galectin network. Materials and Methods: The level of expression of galectin-8 was determined immunohistochemically in a series of 18 and 16 cases of tumor-free epithelium, 24 and 10 cases of low- grade dysplasia, 22 and 15 cases of high-grade dysplasia located in peri-tumoral area of 74 and 37 hypopharyngeal and laryngeal carcinomas. Results: Marked upregulation in galectin-8 staining intensity and immunopositive area in malignancy versus dysplasia was seen in hypopharyngeal cancer (p<10 -6 ), in laryngeal cancer for labeling index and high-grade dysplasia/carcinoma (p<10 -6 ). No correlation to

Variable-field relaxometry of iron-containing human tissues: a preliminary study.

Abstract: Excess iron is found in brain nuclei from neurodegenerative patients (with Parkinson's, Alzheimer's and Huntington's diseases) and also in the liver and spleen of cirrhosis, hemochromatosis and thalassaemia patients. Ferritin, the iron-storing protein of mammals, is known to darken T 2-weighted MR images. Understanding NMR tissue behavior may make it possible to detect those diseases, to follow their evolution and finally to establish a protocol for non-invasive measurement of an organ's iron content using MRI methods. In this preliminary work, the MR relaxation properties of embalmed iron-containing tissues were studied as well as their potential correlation with the iron content of these tissues. Relaxometric measurements (T 1 and T 2) of embalmed samples of brain nuclei (caudate nucleus, dentate nucleus, globus pallidus, putamen, red nucleus and substantia nigra), liver and spleen from six donors were made at different magnetic fields (0.00023-14 T). The influence of the inter-echo time on transverse relaxation was also studied. Moreover, iron content of tissues was determined by inductively coupled plasma atomic emission spectroscopy. In brain nuclei, 1/T 2 increases quadratically with the field and depends on the inter-echo time in CPMG sequences at high fields, both features compatible with an outer sphere relaxation theory. In liver and spleen, 1/T 2 increases linearly with the field and depends on the inter-echo time at all fields. In our study, a correlation between 1/T 2 and iron concentration is observed. Explaining the relaxation mechanism for these tissues is likely to require a combination of several models. The value of 1/T 2 at high field could be used to evaluate iron accumulation in vivo. In the future, confirmation of those features is expected to be achieved from measurements of fresh (not embalmed) human tissues. Copyright © 2009 John Wiley & Sons, Ltd.

Adhesion/growth-regulatory tissue lectin galectin-1 in relation to angiogenesis/lymphocyte infiltration and prognostic relevance of stromal up-regulation in laryngeal carcinomas.

Abstract: Background: Galectin-1 has been found to modulate lymphocyte invasion in inflammation and to be involved in angiogenesis in models, thus prompting examination of its clinical relevance in laryngeal cancer. Patients and Methods: Immunohistochemical processing of tissue sections (n=53) from patients with stage I/II (n=35) and stage IV (n=18) laryngeal squamous cell carcinoma (LSCC) with a specific anti-galectin-1 antibody and monitoring of CD45/CD31 positivity was combined with quantitative morphometric analysis. Results: Lectin presence in the tumor and endothelial cells was positively correlated, while a negative relationship to the number of CD45-positive lymphocytes was demonstrated. No association was seen with the extent of neovascularization. The mean optical density (MOD) of lectin- dependent staining in the tumor stroma was significantly increased compared to normal stroma. Conclusion: Galectin-1 was not associated with angiogenesis in the studied cohort while galectin-1 in endothelial cells may negatively influence lymphocyte invasion and the mean optical density for the stromal galectin-1 signal is up-regulated in tumors. Tumor cell behaviour is necessarily determined by the expression of effectors and the reactivity to microenvironmental factors, for example from the stroma. Due to the increasing realization that the glycan part of cellular glycoconjugates is a rich source of biochemical signals, the basis of the concept of the sugar code, increasing attention is being directed to delineate the relationship of these properties to tumor features (1). In this context, endogenous lectins act as "translators" and elicit potent

The helicase-like transcription factor is a strong predictor of recurrence in hypopharyngeal but not in laryngeal squamous cell carcinomas

Abstract: Aims: To examine the immunohistochemical expression of helicase-like transcription factor (HLTF) in relation to the prognosis of hypopharyngeal (HSCCs) and laryngeal (LSCCs) squamous cell carcinomas, and to characterize the HLTF protein variants expressed in biopsy specimens of head and neck squamous cell carcinoma (HNSCC) as well as the HeLa cell line. Methods and results: HLTF expression was determined by immunohistochemistry on a series of 100 hypopharyngeal (stage IV) and 56 laryngeal SCCs (stages I, II and IV). The HLTF variants were defined using reverse transcriptase-polymerase chain reaction and Western blots in 13 fresh HNSCC biopsies and in HeLa cells. High levels of HLTF expression were associated with rapid recurrence rates in a subgroup of 81 stage IV hypopharyngeal SCCs (with complete follow-up). A 95-kDa HLTF variant truncated at the carboxyl-terminal domain was detected in addition to the 115-kDa full-size protein in HNSCC biopsies, while six variants were observed in HeLa cells. Conclusions: Our results demonstrate, for the first time, that hypopharyngeal SCCs presenting high levels of HLTF have a worse prognosis. The quantitative determination of HLTF in hypopharyngeal SCCs was an independent prognostic marker alongside tumour node metastasis staging. HNSCCs expressed the truncated HLTF variant lacking the domains involved in DNA repair.

Implication des papillomavirus humains dans les cancers des voies aérodigestives supérieures

Abstract: Human papillomavirus (HPV) is one of the most common causes of sexually transmitted infection in the world. France and Belgium present one of the highest incidence of head and neck squamous cell carcinomas (HNSCC) worldwide. Besides, considering only the male population, HNSCCs represent the fourth most frequent cancer after prostate, lung and colon cancers. Although the causal link between high-risk HPVs and cervical carcinoma is well established, the implication of this viral infection in HNSCC remains debatable. Here, we discuss current knowledge concerning the HPV implication in HNSCCs. Based on our literature review, 20 to 25% of HNSCCs could be associated with oncogenic HPVs, in particular HPV type 16. The oropharynx--more precisely the tonsil--is the head and neck location presenting the highest incidence of HPV infection. Moreover, a clear increase of tonsillar carcinoma incidence has been described. As observed in cervical carcinomas, HPV positive HNSCCs are sexually transmitted and characterized by alterations of p53 and pRb signalling pathways. Several studies have shown that HPV positive subgroup presented better prognosis particularly if these patients overexpressed p16INK4. New studies regarding HPV status in HNSCCs are warranted to provide a rationale for large scale HPV vaccination in young male populations.

In vivo assessment of temozolomide delivery systems for inhalation therapy of lung cancer

Abstract: In Vivo Assessment of Temozolomide Local Delivery for Lung Cancer Inhalation Therapy Nathalie Wauthoz, Philippe Deleuze, Julien Hecq, Isabelle Roland, Sven Saussez, Ivan Adanja, Olivier Debeir, Christine Decaestecker, Veronique Mathieu, Karim Amighi Laboratoire de Pharmacie Galenique et de Biopharmacie Director : Karim Amighi Abstract The aim of this study was to compare the efficacy of local drug delivery by inhalation to intravenous delivery in a B16F10 melanoma metastatic lung model. Temozolomide was formulated as a suspension, which was elaborated and evaluated in terms of particle size, shape and agglomeration. An endotracheal administration device was used to aerosolize the suspension. This mode of delivery was evaluated at different temozolomide concentrations and was optimized for the uniformity of delivered dose, the droplet size distribution and the distribution of droplets in vivo. Of the particles in the stabilized suspension, 79% were compatible with the human respirable size range, and this formulation retained 100% in vitro anticancer activity as compared to temozolomide alone in three distinct cancer cell lines. The pulmonary delivery device provided good reproducibility in terms of both the dose delivered and the droplet size distribution. Most of the lung tissues that were exposed to aerosol droplets contained the particles, as revealed by fluorescent microscopy techniques. The global in vivo antitumor activity of the inhaled temozolomide provided a median survival period similar to that for intravenous temozolomide delivery, and three out of twenty-seven mice (11%) survived with almost complete eradication of the lung tumours. The present study thus shows that inhalation of a simple liquid formulation is well tolerated and active against a very biologically aggressive mouse melanoma pulmonary pseudo-metastatic model. This inhalation delivery could be used to deliver other types of anticancer drugs.