HOUSTON A family of microRNAs (miR-200) blocks cancer progression and metastasis by stifling a tumor's ability to weave new blood vessels to support itself, researchers at The University of Texas MD Anderson Cancer Center report today in Nature Communications.
Patients with lung, ovarian, kidney or triple-negative breast cancers live longer if they have high levels of miR-200 expression, the researchers found.
Subsequent experiments showed for the first time that miR-200 hinders new blood vessel development, or angiogenesis, and does so by targeting cytokines interleukin-8 (IL-8) and CXCL1.
"Nanoparticle delivery of miR-200 blocked new blood vessel development, reduced cancer burden and inhibited metastasis in mouse models of all four cancers," said Anil Sood, M.D., professor of Gynecologic Oncology, senior author of the study.
The team's findings highlight the therapeutic potential of nanoparticle-delivered miR-200 and of IL-8 as a possible biomarker for identifying patients who might benefit from treatment. Sood said safety studies will need to be completed before clinical development can begin.
Micro RNAs do not code for genes like their cousins, the messenger RNAs. They regulate gene activation and expression.
"We initially looked at miR-200 because we have an approach for targeting and delivering these molecules with nanoparticles and miR-200 is known to inhibit EMT, a cellular transition associated with cancer progression and metastasis," said Sood, who also holds the Bettyann Asche Murray Distinguished Professorship in Ovarian Cancer Research.
First author Chad Pecot, M.D., a fellow in Cancer Medicine, said initial research provided a new perspective. "Cautionary tales emerged from the literature about poor outcomes in hormone-positive breast cancer, so we decided to delve more deeply into understanding the mechanisms involved."
miR-200 effect differs by breast cancer
|Contact: Scott Merville|
University of Texas M. D. Anderson Cancer Center