Androgens and estrogens stimulate ribosome biogenesis in prostate and breast cancer cells in receptor dependent manner

• Oestrogen and androgen positively regulate the initial stage of ribosome biogenesis.
• Activation of rRNA gene transcription is receptor dependent.
• Activation can be blocked by hormone antagonists.
• Preliminary analysis shows presence of estrogen receptor at rDNA.
• Initial stages of the transcription cycle but not elongation are affected.

Ribosome biogenesis is a fundamental cellular process intimately linked to cell growth and proliferation, which is upregulated in most of cancers especially in aggressive cancers. In breast and prostate cancers steroid hormone receptor signalling is the principal stimulus for cancer growth and progression. Here we investigated the link between estrogen and androgen receptor signalling and the initial stage of ribosome biogenesis — transcription of rRNA genes. We have discovered that oestrogen or androgen treatment can positively regulate rRNA synthesis in breast and prostate cancer cells respectively and that this effect is receptor dependent. This novel and interesting finding suggests a previously unidentified link between steroid hormone receptor signalling pathways and the regulation of ribosome biogenesis.