Juvenile polyposis syndrome (JPS) and hereditary haemorrhagic telangiectasia (HHT) are autosomal dominant disorders with characteristic clinical phenotypes. Recently, reports of the combined syndrome of JPS and HHT have been described in individuals with mutations in the SMAD4 gene, whose product-SMAD4-is a critical intracellular effector in the signalling pathway of transforming growth factor ...

Hereditary hemochromatosis, characterized by iron overload in multiple organs, is one of the most common genetic disorders among Caucasians. Hepcidin, which is synthesized in the liver, plays important roles in iron overload syndromes. Here, we show that a Cre-loxP-mediated liver-specific disruption of SMAD4 results in markedly decreased hepcidin expression and accumulation of iron in many orga...

BACKGROUND Pancreatic adenocarcinoma comprises 85% of all cases of pancreatic malignancies. From a diagnostic standpoint, these tumors are readily diagnosed by fine needle aspiration, with an accuracy of greater than 90%; however it is often difficult to ascertain whether these are primary or metastatic in nature. This study was undertaken to see the usefulness of CK19, CA19-9 and a newly descr...

Transforming growth factor-beta (TGF-beta) inhibits cell proliferation in many cell types, and acquisition of TGF-beta resistance has been linked to tumorigenesis. One class of proteins that plays a key role in the TGF-beta signal transduction pathway is the SMAD protein family. MDM2, a key negative regulator of p53, has recently been shown to suppress TGF-beta-induced growth arrest in a p53-in...

Regulation of osteoblast and osteocyte viability is essential for bone homeostasis. Smad4, a major transducer of bone morphogenetic protein and transforming growth factor-β signaling pathways, regulates apoptosis in various cell types through a mitochondrial pathway. However, it remains poorly understood whether Smad4 is necessary for the regulation of osteoblast and osteocyte viability. In thi...

Matrix metalloproteinases (MMPs) play crucial roles in extravillous trophoblast invasion. In the present study, we examined the possible role of Smad4 and Smad2 in transforming growth factor (TGF)-beta1-induced MMP-2 expression, using the well-established invasive extravillous trophoblast cell line HTR-8/SVneo. Recombinant sense Smad4 or Smad2 retroviral vectors were constructed by inserting fu...

Pancreatic ductal adenocarcinoma (PDAC) is the fourth most common cause of cancer death in North America. Activating KRAS mutations and Smad4 loss occur in approximately 90% and 55% of PDAC, respectively. While their roles in the early stages of PDAC development have been confirmed in genetically modified mouse models, their roles in the multistep malignant transformation of human pancreatic du...

Assembly of the multi-subunit eukaryotic translation initiation factor-4F (eIF4F) is critical for protein synthesis and cell growth and proliferation. eIF4F formation is regulated by the translation-inhibitory protein 4E-BP1. While proliferation factors and intracellular pathways that impinge upon 4E-BP1 phosphorylation have been extensively studied, how they control 4E-BP1 expression remains u...

PURPOSE This study investigated the effects of microRNA-483-3p (miR-483-3p) on extracellular matrix (ECM) production, and clarified the regulatory mechanism of microRNA-483-3p in human trabecular meshwork cells (HTMCs) under oxidative stress. METHODS The expression levels of ECM (fibronectin, laminin, collagen I) in HTMCs under oxidative stress were measured by Western blot. Changes of miR-48...

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer mortality. Although advances have been made in understanding the pathogenesis of PDAC, the outcome still remains poor. The aim of this study is to conduct a meta-analysis to evaluate the precise association between SMAD4 loss and clinicopathological significance in PDAC. A literature search was made in PubMed, Web of...