Project description:Our understanding of posttranscriptional modifications that decorate RNA, a regulatory layer positioned between DNA and proteins, is in its infancy. N6-methyladenosine (m6A) is the most prevalent internal modification in messenger RNAs that is installed and erased by m6A methyltransferases and demethylases. The importance of these enzymes in cancer is rapidly emerging, yet information of their specific mode of actions during disease progression remain largely unknown. In the present study, we report that the m6A RNA demethylase FTO controls EMT and invasion in cancer through regulation of the Wnt pathway. We find that loss of FTO, in contrast to acute myeloid leukemia, is frequent in many cancer types, including breast and prostate cancers. Knockdown of FTO promotes tumor progression – specifically migration and invasion – in breast and prostate cancer cells. Furthermore, implantation of these cells accelerates tumor progression in recipient mice in vivo. In these tumors, FTO depletion leads to m6A-dependent activation of Wnt signaling, which drives an enhanced EMT program and invasion, thus leading to poor clinical outcome. However, loss of FTO also sensitizes cancers cells to Wnt inhibition, offering a rationale for the therapeutic targeting of Wnt for cancer patients with low FTO levels. Together, our work reveals FTO as a novel regulator of EMT and an unexpected mechanism by which Wnt signals are dysregulated in tumors, providing a rationale to stratify cancer patients treated with Wnt inhibitor. These data uncover a previously unrecognized relationship between RNA modification and EMT in cancer.
Project description:Our understanding of posttranscriptional modifications that decorate RNA, a regulatory layer positioned between DNA and proteins, is in its infancy. N6-methyladenosine (m6A) is the most prevalent internal modification in messenger RNAs that is installed and erased by m6A methyltransferases and demethylases. The importance of these enzymes in cancer is rapidly emerging, yet information of their specific mode of actions during disease progression remain largely unknown. In the present study, we report that the m6A RNA demethylase FTO controls EMT and invasion in cancer through regulation of the Wnt pathway. We find that loss of FTO, in contrast to acute myeloid leukemia, is frequent in many cancer types, including breast and prostate cancers. Knockdown of FTO promotes tumor progression – specifically migration and invasion – in breast and prostate cancer cells. Furthermore, implantation of these cells accelerates tumor progression in recipient mice in vivo. In these tumors, FTO depletion leads to m6A-dependent activation of Wnt signaling, which drives an enhanced EMT program and invasion, thus leading to poor clinical outcome. However, loss of FTO also sensitizes cancers cells to Wnt inhibition, offering a rationale for the therapeutic targeting of Wnt for cancer patients with low FTO levels. Together, our work reveals FTO as a novel regulator of EMT and an unexpected mechanism by which Wnt signals are dysregulated in tumors, providing a rationale to stratify cancer patients treated with Wnt inhibitor. These data uncover a previously unrecognized relationship between RNA modification and EMT in cancer.
