MicroRNA Acts as Tumor Suppressor in Mouse Lung Cancer Model

MicroRNAs (miRNAs) are small, noncoding RNA molecules that occur naturally in human cells.

Misregulation of these critical cellular components is a frequent event in the development of genetically manifested human diseases such as cancer.

Investigators at Yale University (New Haven, CT, USA) and their colleagues at Mirna Therapeutics (Austin, TX, USA) have been working with the let-7 family of mRNAs. In the current study, they examined the link between let-7 and non-small-cell lung cancer (NSCLC) in a mouse model.

Results published in the December 7, 2009, online edition of the journal Oncogene revealed that let-7 acted as a tumor suppressor, since loss of let-7 function enhanced lung tumor formation. Treatment of mice with existing tumors with let-7 reduced the number and size of the tumors by almost two-thirds.

"This is the first time anybody has shown a positive effect of microRNAs in shrinking lung cancer," said senior author Dr. Frank Slack, professor of molecular, cellular, and developmental biology at Yale University. "We hope it will be valuable in the treatment of many other forms of cancer."

The investigators are now conducting studies to determine whether let-7 therapy in combination with chemotherapy and radiation can induce full remission.

Related Links:
Yale University
Mirna Therapeutics