Researchers at Cold Spring Harbor Laboratory say they have created a new treatment that could have a dramatic effect on blunting metastatic breast cancer.
Using an antisense oligonucleotide, the team--working with Ionis Pharmaceuticals, formerly Isis--focused on Malat1, part of a class of nucleic acids referred to as long noncoding RNAs.
Although the function of Malat1 in normal cells isn't entirely clear, the researchers are confident it has an important role in cancer only since they created a genetic mouse missing the Malat1 gene--reporting no unusual abnormalities. They made the same genetic mouse model, this time with a human metastatic breast cancer, and found that the aggressive cancer cells became "differentiated" and were less likely to spread.
"We got an amazing result," Spector says. "By removing Malat1--this one, single long non-coding RNA--we made a dramatic impact on the primary breast tumors in these mice. The tumors took on a wholly new character."
"We are very pleased and excited by this result," Spector says, "because it suggests that these metastatic tumors have a dependency on Malat1--they can't thrive without it. And very importantly, targeting Malat1 should not have a deleterious effect on any normal cells."
By isolating these nonmetastatic cancer cells from mice that lack Malat1 the researchers are further clarifying the role of Malat1 on controlling cell growth and migration, characteristic of breast cancer cells, as well as many other types of cancers.
The researchers plan to launch clinical trials soon after further preclinical experiments are conducted.