A protein called BRD7 activates the famous p53 tumor suppressor protein and thus stops the growth of cancerous tumors, researchers in the Netherlands report in the journal Nature Cell Biology.
It has long been known that the transcription factor p53 is a very important tumor suppressor protein, i.e. it is known to inhibit the growth of tumors. Inactivating this protein leads to the development of many types of cancer.
Expression of the gene encoding the BRD7 protein is often silenced in breast cancer cells, but it has not yet been known how the BRD7 protein may influence the development of tumors.
Reuven Agami and colleagues at the Dutch Cancer Research Institute in Amsterdam showed that BRD7 binds to p53 and activates it, thereby inhibiting the growth of cancer. In addition, BRD7 also affects the structure of chromatin in the location of genes whose expression is regulated by p53 and enables their better activation.
As the researchers observed, loss of BRD7 from human cells grown in the laboratory triggers uncontrolled cell division and neoplastic transformation of the cells.
Scientists examined more than 2000 samples – breast cancer slices, and found that BRD7 expression is turned off only in p53-controlled tumors, confirming their described mechanism of BRD7 control of this protein activity. (PAP)