Project description:RNA methylation plays an important role fine tuning translation and subsequently regulating cellular responses and cell fate. The fat mass- and obesity-associated protein (FTO) was recognized as an m6A demethylase and described as an oncogenic factor in leukemia and brain tumors. FTO expression levels are suppressed in ovarian tumors and ovarian cancer stem cells (CSCs). FTO induce cyclic AMP activity through targeting PDE4B and PDE1C by down-regulation of m6A levels in the mRNA transcript. In all or findings point to a tumor suppressor function of FTO in high grade serous OC. FTO induce cyclic AMP activity through targeting PDE4B and PDE1C by down-regulation of m6A levels in the mRNA transcript. In all or findings point to a tumor suppressor function of FTO in high grade serous OC
Project description:RNA methylation plays an important role fine tuning translation and subsequently regulating cellular responses and cell fate. The fat mass- and obesity-associated protein (FTO) was recognized as an m6A demethylase and described as an oncogenic factor in leukemia and brain tumors. FTO expression levels are suppressed in ovarian tumors and ovarian cancer stem cells (CSCs). FTO induce cyclic AMP activity through targeting PDE4B and PDE1C by down-regulation of m6A levels in the mRNA transcript. In all or findings point to a tumor suppressor function of FTO in high grade serous OC
Project description:Multifunctional N6-methyladenosine (m6A) has been revealed to be an important epigenetic component in various physiological and pathological processes, but its role in female ovarian aging remains unclear. Thus, we demonstrated m6A demethylase FTO downregulation and the ensuing increased m6A in granulosa cells (GCs) of human aged ovaries, while FTO-knockdown GCs showed faster aging-related phenotypes mediated. Using the m6A-RNA-sequence technique (m6A-seq), increased m6A was found in the FOS-mRNA-3'UTR, which is suggested to be an erasing target of FTO that slows the degradation of FOS-mRNA to upregulate FOS expression in GCs, eventually resulting in GC-mediated ovarian aging. FTO acts as a senescence-retarding protein via m6A, and FOS knockdown significantly alleviates the aging of FTO-knockdown GCs.
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:Single nucleotide polymorphisms in the FTO gene encoding a m6A demthylase are associated with obesity and cancer development. However, the functional role of FTO in the developemnt of progression of hepatocellular carcinoma (HCC) as a proteotypic obesity-associated cancer remains unclear. Here, we have generated mice with hepatic FTO deficiency (FTOL-KO) and subjected them to DEN induced HCC-development. FTOL-KO mice exhibit increased HCC burden. While control mice exhibit a dynamic regulation of FTO upon induction of liver damage, this response is abrogated in mice lacking FTO. Proteomic analyses revealed that liver damage-induced increases in FTO expression promotes m6A-demethylation of CUL4A reducing its protein expression. Functionally, knockdown of CUL4A restores the increased hepatocyte proliferation observed upon loss of FTO. Collectively, our study reveals a protective role for FTO-dependent dynamic m6A mRNA demethylation of CUL4A in the initiation of HCC development.
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:Single nucleotide polymorphisms in intron 1 of the fat mass and obesity-associated (FTO) gene were found to be associated with an increased risk of adult obesity. Enhanced FTO expression in mice leads to hyperphagia, increased fat mass, and higher body weight. Neuronal-specific FTOâ??deleted mice have an identical lean body weight phenotype to global FTO-deleted mice. The physiological role of adipose FTO in the homeostasis of energy regulation remains to be elucidated. We used microarrays to elucidate the metabolic pathways that are regulated by FTO in the white fat. FTO flox/flox and Adiponectin-cre FTO flox/flox (AFO) mice were fed with chow diet. White fat tissues from epididymal adipose pad were harvested under ad lib condition for RNA isolation. Three independent pools of FTO flox/flox and AFO mouse white fat RNA were included in the study.
Project description:FTO, an N6-methyladenosine (m6A) demethylase, can promote cervical cancer cell proliferation and migration. RNA-sequencing of SiHa cells with FTO knockdown was conducted to dissect the differentially expressed genes and the potential mechanism of FTO in cervical cancer.