[Functional modeling for risk analysis in radiotherapy]

PURPOSE

This document presents a systematic and structured approach for functional modeling for risk analysis in radiotherapy, aiming to reconcile the need, on one hand, for a method that can be applied generally and, on the other hand, for a method that provides a highly precise model.

MATERIALS AND METHODS

The approach relies on new functional structuring patterns and flux analysis, derived from system engineering and knowledge engineering.

RESULTS

The method affords strong support for the development of detailed models of the patient's process through a department of radiotherapy. Lack of structure of the actual process in a particular department may be easily identified leading to the development of specific procedures for the improvement of security.

CONCLUSION

Modeling approach derived from engineering may be used for functional modeling for risk analysis in radiotherapy.

Whole slide quantification of stromal lymphatic vessel distribution and peritumoral lymphatic vessel density in early invasive cervical cancer: a method description

Peritumoral Lymphatic Vessel Density (LVD) is considered to be a predictive marker for the presence of lymph node metastases in cervical cancer. However, when LVD quantification relies on conventional optical microscopy and the hot spot technique, interobserver variability is significant and yields inconsistent conclusions. In this work, we describe an original method that applies computed image analysis to whole slide scanned tissue sections following immunohistochemical lymphatic vessel staining. This procedure allows to determine an objective LVD quantification as well as the lymphatic vessel distribution and its heterogeneity within the stroma surrounding the invasive tumor bundles. The proposed technique can be useful to better characterize lymphatic vessel interactions with tumor cells and could potentially impact on prognosis and therapeutic decisions.

[Securitization of the bi-site radiotherapy activity as part of the resumption of treatments in the Hospital of Epinal by the team of Alexis Vautrin Nancy Cancer Center]

In February 2007, the radiation therapy department of the Jean Monnet Hospital in Epinal (France) has stopped the radiotherapy treatments after the discovery of a radiotherapy accident and bad practices leading to overexposure of patients between 1987 and 2006. The Regional Cancer Center "Centre Alexis Vautrin" in Nancy (France) was given the task of the new start of treatment activity. From February 2007 to January 2008, actions of training, updates of equipments and practices have been performed in the Epinal Hospital, guided by the quality approach, allowing the treatment of new patients in February 2008, with the radiation oncologists and the medical physicists of the Centre Alexis Vautrin, with the highest conditions of security and confidence.

The metalloproteinase ADAM-12 regulates bronchial epithelial cell proliferation and apoptosis

OBJECTIVES

The ADAMs (a disintegrin and metalloproteinase) enzymes compose a family of membrane-bound proteins characterized by their multi-domain structure and ADAM-12 expression is elevated in human non-small cell lung cancers. The aim of this study was to investigate the roles played by ADAM-12 in critical steps of bronchial cell transformation during carcinogenesis.

MATERIALS AND METHODS

To assess the role of ADAM-12 in tumorigenicity, BEAS-2B cells were transfected with a plasmid encoding human full-length ADAM-12 cDNA, and then the effects of ADAM-12 overexpression on cell behaviour were explored. Treatment of clones with heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) neutralizing antibodies as well as an EGFR inhibitor allowed the dissection of mechanisms regulating cell proliferation and apoptosis.

RESULTS

Overexpression of ADAM-12 in BEAS-2B cells promoted cell proliferation. ADAM-12 overexpressing clones produced higher quantities of HB-EGF in their culture medium which may rely on membrane-bound HB-EGF shedding by ADAM-12. Targeting HB-EGF activity with a neutralizing antibody abrogated enhanced cell proliferation in the ADAM-12 overexpressing clones. In sharp contrast, targeting of amphiregulin, EGF or transforming growth factor-alpha failed to influence cell proliferation; moreover, ADAM-12 transfectants were resistant to etoposide-induced apoptosis and the use of a neutralizing antibody against HB-EGF activity restored rates of apoptosis to be similar to controls.

CONCLUSIONS

ADAM-12 contributes to enhancing HB-EGF shedding from plasma membranes leading to increased cell proliferation and reduced apoptosis in this bronchial epithelial cell line.