The presence of steroid hormone receptors correlates with various biological characteristics in breast and endometrium cancer. Certain tumours produce growth factors, which cause growth stimulation in an autocrine way.
It is generally acknowledged that the receptor status of a tumour has prognostic significance and is used in the decision whether endocrine treatment will be given.
The project will focus on the standardization of the measurement of epidermal growth factors (EGF) and growth factor receptors (EGFR) in malignant breast cancer tumours. This consists of three Phases: Phase I: The preparation of the iodinated radio active ligand, the preparation of the lyophilized reference membrane sample and research for a reference parameter for expressing assay results. Phase II: Validation and design of the assay in such a way that it may be even implemented by not highly specialized laboratories. Phase III: Organization of the relative Quality control (QC) programme involving a large number of laboratories from the Members States. In addition, the statistical evaluation of the data provided by the aforementioned laboratories is foreseen.
Six iodination methods have been evaluated and three of them resulted in 125I-mEGF molecules showing identical binding behaviour to the EGFR when compared to native EGF. Also no or negligible amounts of oxidized EGF moieties were demonstrated by HPLC. Tracers prepared by any of these methods are equally suitable to measure EGFR in human tissue membrane preparations. In addition the hydroxilapatite (HAP) method, for separating bound and free ligand in the assay of EGFR, was evaluated and assessed to be satisfactory. With respect to the software to calculate receptor binding data obtained with HAP-assay, consensus was reached by the participants to try to use the same one in every laboratory. Completion of this phase of the project is expected in mid 1992. Subsequently the design of a complete assay for the EGFR may be envisaged with a large number of participants involved.
Funding SchemeCSC - Cost-sharing contracts