Project description:Loss of olfactomedin 4 (OLFM4) gene expression is associated with the progression of human prostate cancer, but its role and the molecular mechanisms involved in this process have not been completely understood. In this study, we found that Olfm4-knockout mice developed prostatic intraepithelial neoplasia and prostatic adenocarcinoma. Importantly, we found that the hedgehog-signaling pathway was significantly upregulated in the Olfm4-knockout mouse model. We also found that restoration of OLFM4 in human prostate-cancer cells that lack OLFM4 expression significantly downregulated hedgehog signaling-pathway component expression. Furthermore, we demonstrated that the OLFM4 protein interacts with sonic hedgehog protein, as well as significantly inhibits GLI-reporter activity. Bioinformatic and immunohistochemistry analyses revealed that decreased OLFM4 and increased SHH expression was significantly associated with advanced human prostate cancer. Thus, olfactomedin 4 appears to play a critical role in regulating progression of prostate cancer, and has potential as a new biomarker for prostate cancer.
Project description:Origins of the brain tumor, medulloblastoma, from stem cells or restricted pro-genitor cells are unclear. To investigate this, we activated oncogenic Hedgehog signaling in multipotent and lineage-restricted CNS progenitors. We observed that normal unipo-tent cerebellar granule neuron precursors (CGNP) derive from hGFAP+ and Olig2+ rhombic lip progenitors. Hedgehog activation in a spectrum of early and late stage CNS progenitors generated similar medulloblastomas, but not other brain cancers, indicating that acquisition of CGNP identity is essential for tumorigenesis. We show in human and mouse medulloblastoma that cells expressing the glia-associated markers Gfap and Olig2 are neoplastic and that they retain features of embryonic-type granule lineage progenitors. Thus, oncogenic Hedgehog signaling promotes medulloblastoma from lineage-restricted granule cell progenitors. Gene expression profiling of cerebellar tumors generated from various early and late stage CNS progenitor cells. Experiment Overall Design: Group comparisons with biological replicates
Project description:FLT3/ITD-SmoM2 mice developed rapidly fatal myeloid leukemia compared to FLT3/ITD only mice, suggesting that overactivation of the Hedgehog signaling pathway via SmoM2 can drive myeloid disease progression We used the Affymetrix Mouse 430_2.0 microarray to detail global gene expression responsible for disease progression in sorted bone marrow cells and found that the Hedgehog signaling pathway contributes to disease progression by enhancing FLT3 signaling
Project description:Wnt signaling is a complex pathway consisting of numerous ligands and frizzled (FZD) receptors. These signaling components are widely expressed in human prostate tissues and often undergo upregulation or mutation in advanced prostate cancers. Enhanced Wnt signaling promotes prostate cancer cell proliferation, metastasis, and resistance to therapy. However, targeting pan-Wnt signaling poses challenges due to tissue toxicity. We show that FZD6 is the most highly expressed and frequently amplified Wnt receptor in advanced human prostate cancers. Knockdown of FZD6 suppresses in vitro growth of various prostate cancer cell lines. Additionally, FZD6 knockdown impairs DNA double-strand break (DSB) repair, as determined by both resolution of γH2AX foci and DNA DSB repair reporter assays. Mechanistically, FZD6 knockdown-induced growth suppression is linked to reduced activities of the SRC kinase and STAT3, while DNA damage repair deficiency is mediated through WEE1 downregulation. WEE1 downregulation is mediated through PLK1 but is independent of β-Catenin. Knockdown of FZD6 enhances the therapeutic efficacy of genotoxic agents in preclinical prostate cancer models. Our findings demonstrate that targeting a single FZD receptor highly expressed in prostate cancers can achieve significant therapeutic efficacy.
Project description:Cancer associated fibroblasts (CAFs) play a pivotal role in tumor progression, but it remains elusive whether and how PTEN-deficient prostate cancers reprogram CAFs to overcome the barriers for tumor progression. Herein, we report that PTEN deficiency induces KLF5 acetylation; and interruption of KLF5 acetylation orchestrates intricate interactions between cancer cells and CAFs that enhance FGFR1 signaling and promote tumor growth. Deacetylated KLF5 promotes tumor cells to secrete TNF-α, which stimulates inflammatory CAFs to release FGF9. CX3CR1 inhibition blocks FGFR1 activation triggered by FGF9 and sensitizes PTEN-deficient prostate cancer to AKT inhibitor capivasertib.
Project description:Origins of the brain tumor, medulloblastoma, from stem cells or restricted pro-genitor cells are unclear. To investigate this, we activated oncogenic Hedgehog signaling in multipotent and lineage-restricted CNS progenitors. We observed that normal unipo-tent cerebellar granule neuron precursors (CGNP) derive from hGFAP+ and Olig2+ rhombic lip progenitors. Hedgehog activation in a spectrum of early and late stage CNS progenitors generated similar medulloblastomas, but not other brain cancers, indicating that acquisition of CGNP identity is essential for tumorigenesis. We show in human and mouse medulloblastoma that cells expressing the glia-associated markers Gfap and Olig2 are neoplastic and that they retain features of embryonic-type granule lineage progenitors. Thus, oncogenic Hedgehog signaling promotes medulloblastoma from lineage-restricted granule cell progenitors. Gene expression profiling of cerebellar tumors generated from various early and late stage CNS progenitor cells.
