NEW YORK (GenomeWeb) – New evidence has emerged today showing that the inactivation or alteration of cancer suppressor genes can take place even if DNA itself remains unaltered.
Reporting in Nature, investigators demonstrated that changes in mRNA due to a process called intronic polyadenylation (IPA) can drive development of some cancers by altering gene expression in a way that interferes with the proper functioning of tumor suppression mechanisms.
Led by Memorial Sloan Kettering Cancer Center molecular biologist Christine Mayr, the study involved sequencing normal and cancerous cells from a small cohort of patients with chronic lymphocytic leukemia, which revealed that IPA-driven mRNA changes do take place, and that — at least in this cancer type — can occur much more frequently than corresponding mutations in DNA.
A known molecular mechanism for cancer development and spread is the inactivation of tumor suppressor genes, which encode various tools the body uses to keep its cells from turning cancerous.
But evidence is building that the hobbling of tumor suppressors can take place not just due to changes in the DNA itself, but by alterations in messenger RNAs, which act as a go-between, translating the DNA code into its intended function in the body.