[Specific expression of human pS2 gene in breast cancer].

The hormone-dependence of some human breast cancers is well recognized. However, the molecular mechanisms responsible for the growth stimulation of these cancers by oestrogens are still poorly understood. With the hope of elucidating these mechanisms, we have recently cloned and studied the structure-function relationship of the human oestrogen and progestin receptors, and also undertaken a study aimed at characterizing genes whose expression is controlled by oestrogens in hormone-dependent breast cancers. We review here our findings concerning one of these genes and its expression products, the pS2 gene. We discuss also whether a systematic determination of pS2 gene expression in breast cancer biopsies could be useful to establish a new biochemical classification of these cancers which may be useful to improve the diagnosis of hormone-dependent cancers.