Project description:Fibroblast-like synoviocytes (FLS) harbour active migration, invasion, proliferation and decreased cell-contact inhibition, and served as a crucial component in pathogenesis of rheumatoid arthritis. However, the mechanism underlying the aggressive behavior remain unclear. In this study, we established FTO-knockdown RA FLS to investigate the molecular mechanism.
Project description:Fibroblast-like synoviocytes (FLS) are crucial in promoting articular inflammation and destruction in rheumatoid arthritis (RA). As the most abundant RNA modification, the function of m6A in RA FLS is still unclear. Here, we constructed FTO-knockdown FLS to explore the mechanism of FTO in regulating the aggressive behavior of RA FLS.
Project description:Cardiac fibrosis is common in cardiovascular diseases. N6-methyladenosine (m6A) is one of the most common modifications in eukaryotic mRNAs. Previous research has suggested that m6A modification is vital in cardiovascular diseases. The underlying targets of FTO were selected through transcriptome sequencing (RNA-seq) combined with methylated RNA immunoprecipitation sequencing (MeRIP-seq). According to MeRIP-seq and RNA-seq, FTO inhibited collagen synthesis in CFs.
Project description:Cardiac fibrosis is common in cardiovascular diseases. N6-methyladenosine (m6A) is one of the most common modifications in eukaryotic mRNAs. Previous research has suggested that m6A modification is vital in cardiovascular diseases. The underlying targets of FTO were selected through transcriptome sequencing (RNA-seq) combined with methylated RNA immunoprecipitation sequencing (MeRIP-seq). According to MeRIP-seq and RNA-seq, FTO inhibited collagen synthesis in CFs.
Project description:Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease involving primarily the synovial membranes and articular structures of multiple joints. A hallmark of RA is the pseudo-tumoral expansion of fibroblast-like synoviocytes (FLS), as these cells invade and finally destroy the joint structure. RA FLS have been therefore proposed as a therapeutic target. > TNF-related apoptosis-inducing ligand (TRAIL) has been described as a pro-apoptotic factor on malignant cells. The fact that fibroblasts-like-synoviocytes (FLS) in rheumatoid arthritis RA patients exhibit tumor like features led us to investigate the effect of TRAIL on ex-vivo RA FLS. We have previously described that TRAIL induces apoptosis only in a subset of RA FLS, but an induction of proliferation in the surviving cells. This observation corresponds to the pleiotropic effects of TRAIL observed on primary human tumor cells. We also observed that sensitivity to TRAIL-induced apoptosis varied in RA FLS from one patient to another, and was correlated with disease severity. We therefore screened for genes that were differentially expressed in RA FLS sensitive and resistant to TRAIL induced apoptosis in order to understand molecular factors making cells resistant or sensitive to TRAIL induced apoptosis.
Project description:Zinc-finger homeobox 3 (ZFHX3, also known as ATBF1) suppresses prostatic tumorigenesis. ZFHX3 is frequently found to have numerous deletions in human prostate cancer (PCa). However, the underlying molecular function of ZFHX3 during prostatic tumorigenesis is not well understood. N6-methyladenosine (m6A) modification in RNA plays a critical role in the development of cancers; however, the relationship between ZFHX3 and m6A modification is largely unknown in PCa. In this study, we found that ZFHX3 knockdown decreased total m6A levels through enhancing the transcriptional activity of FTO in PCa cells. Importantly, FTO inhibition suppressed cell proliferation and rescued the promoting function of ZFHX3 knockdown on cell proliferation. In vivo, we verified that FTO was upregulated and ZFHX3 was decreased in PCa patients and that a high level of ZFHX3 is indispensable for low FTO expression and is correlated with better patient survival. Through transcriptome sequencing and Me-RIP sequencing, we revealed that E2F2 and CDKN2C were the direct targets of FTO-mediated m6A modification and ZFXH3 was required for the regulation of FTO on E2F2 and CDKN2C expression. Unexpectedly, we uncovered that ZFHX3 expression was in return regulated by FTO in a m6A-dependent way. These findings establish a novel crosstalk mechanism between ZFHX3 and FTO in prostatic tumorigenesis.
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.
Project description:N6-methyladenosine (m6A) RNA methylation is the most abundant internal chemical modifications in eukaryotic messenger RNA (mRNA) as well as long non-coding RNA (lncRNA). Recently, m6A RNA methylation research was revived by the discovery of the fat mass- and obesity-associated protein (FTO) as the first RNA demethylase, implicating that m6A RNA methylation is a reversible and dynamic modification and may have critical biological functions. Emerging evidence has shown that m6A modifications in mRNAs and lncRNAs play crucial roles in regulating RNA fate and function in biological processes in the past several years. As the first identified RNA demethylase that regulates the demethylation of target mRNAs, FTO has been reported to play an oncogenic role in leukemia and glioblastoma stem cells. To identify the target genes of FTO in melanoma cells, we used m6A IP seq coupled with RNA seq to determine the potential demethylation and gene targets across the whole transcriptome for FTO, and identified more than 1,000 genes.
Project description:TNF-like ligand 1A (TL1A) is a member of TNF receptor superfamily and involved in the pathogenesis of autoimmune diseases by inducing apoptosis via intracellular death domain or promoting inflammation through the activation of NFκB by binding to its specific receptor death receptor 3 (DR3). Meanwhile, decoy receptor 3 (DcR3) competitively binds soluble TL1A in addition to Fas-ligand (FasL) and LIGHT and inhibits the signaling of TL1A via DR3. DcR3 overexpressed in rheumatoid synovial fibroblasts (RA-FLS) stimulated with inflammatory cytokines such as TNFα or IL-1β inhibits Fas-induced apoptosis. In contrast, DcR3 inhibited cell proliferation induced by inflammatory cytokines via membrane-bound TL1A expressed on RA-FLS. Therefore, TL1A-DcR3/DR3 signaling may be involved in the pathogenesis of RA by modulating apoptosis and proliferation of RA-FLS. We hypothesized that TL1A regulates the gene expression in RA-FLS. We used to search for genes in which expression in RA-FLS is regulated by the ligation of TL1A.