Introduction: Repeated hepatic arterial delivery of therapeutic agents to the liver by percutaneously implanted port-catheter systems has been widely used to treat unresectable liver cancer. This approach is applied to assess the therapeutic efficacy of repeated low-density lipoprotein-docosahexaenoic acid (LDL-DHA) nanoparticle treatments in a rat model of hepatocellular carcinoma.
Methods: N1S1 hepatoma bearing rats underwent placement of a percutaneously implanted hepatic artery port-catheter system and were allocated to untreated, control LDL-triolein (LDL-TO) or LDL-DHA nanoparticle infusions groups.
In adult males, spermatogonia maintain lifelong spermatozoa production for oocyte fertilization. To understand spermatogonial metabolism we compared gene profiles in rat spermatogonia to publicly available mouse, monkey, and human spermatogonial gene profiles. Interestingly, rat spermatogonia expressed metabolic control factors , , and Germline Foxa2 was enriched in Gfra1 and Gfra1 undifferentiated A-single spermatogonia.
View Article and Find Full Text PDFHepatic-arterial infusion (HAI) of low-density lipoprotein (LDL) nanoparticles reconstituted with docosahexaenoic acid (DHA) (LDL-DHA) has been shown in a rat hepatoma model to be a promising treatment for hepatocellular carcinoma. To date, little is known regarding the safety of HAI of LDL-DHA to the liver. Therefore, we aimed to investigate the deposition, metabolism and safety of HAI of LDL-DHA (2, 4 or 8 mg/kg) in the rat.
View Article and Find Full Text PDFBackground: In recent years, small animal arterial port-catheter systems have been implemented in rodents with reasonable success. The aim of the current study is to employ the small animal port-catheter system to evaluate the safety of multiple hepatic-artery infusions (HAI) of low-density lipoprotein-docosahexaenoic acid (LDL-DHA) nanoparticles to the rat liver.
Methods: Wistar rats underwent surgical placement of indwelling HAI ports.
Hsp90 plays an important role in health and is a therapeutic target for managing misfolding disease. Compounds that disrupt co-chaperone delivery of clients to Hsp90 target a subset of Hsp90 activities, thereby minimizing the toxicity of pan-Hsp90 inhibitors. Here, we have identified SEW04784 as a first-in-class inhibitor of the Aha1-stimulated Hsp90 ATPase activity without inhibiting basal Hsp90 ATPase.
View Article and Find Full Text PDFLipoproteins are a family of naturally occurring macromolecular complexes consisting amphiphilic apoproteins, phospholipids, and neutral lipids. The physiological role of mammalian plasma lipoproteins is to transport their apolar cargo (primarily cholesterol and triglyceride) to their respective destinations through a highly organized ligand-receptor recognition system. Current day synthetic nanoparticle delivery systems attempt to accomplish this task; however, many only manage to achieve limited results.
View Article and Find Full Text PDFId helix-loop-helix (HLH) proteins (Id1-4) bind E protein bHLH transcription factors, preventing them from forming active transcription complexes that drive changes in cell states. Id proteins are primarily expressed during development to inhibit differentiation, but they become re-expressed in adult tissues in diseases of the vasculature and cancer. We show that the genetic loss of Id1/Id3 reduces ocular neovascularization in mouse models of wet age-related macular degeneration (AMD) and retinopathy of prematurity (ROP).
View Article and Find Full Text PDFCastration-resistant prostate cancer (CRPC) is the emergence of prostate cancer cells that have adapted to the androgen-depleted environment of the prostate. In recent years, targeting multiple chaperones and co-chaperones (e.g.
View Article and Find Full Text PDFGiven that mutated p53 (50% of all human cancers) is over-expressed in many cancers, restoration of mutant p53 to its wild type biological function has been sought after as cancer therapy. The conformational flexibility has allowed to restore the normal biological function of mutant p53 by short peptides and small molecule compounds. Recently, studies have focused on physiological mechanisms such as acetylation of lysine residues to rescue the wild type activity of mutant p53.
View Article and Find Full Text PDFID4, a helix loop helix transcriptional regulator has emerged as a tumor suppressor in prostate cancer. Epigenetic silencing of ID4 promotes prostate cancer whereas ectopic expression in prostate cancer cell lines blocks cancer phenotype. To directly investigate the anti-tumor property, full length human recombinant ID4 encapsulated in biodegradable Polycaprolactone/Maltodextrin (PCL-MD) nano-carrier was delivered to LNCaP cells in which the native ID4 was stably silenced (LNCaP(-)ID4).
View Article and Find Full Text PDFBiochem Biophys Res Commun
September 2016
Deregulation of tumor suppressor genes is associated with tumorigenesis and the development of cancer. In prostate cancer, ID4 is epigenetically silenced and acts as a tumor suppressor. In normal prostate epithelial cells, ID4 collaborates with androgen receptor (AR) and p53 to exert its tumor suppressor activity.
View Article and Find Full Text PDFBackground: 2'-5' oligoadenylate synthetases (OAS) are interferon inducible enzymes that polymerizes ATP to 2'-5'-linked oligomers of adenylate (2-5As). As part of the innate immune response, these enzymes are activated by viral double stranded RNA or mRNAs with significant double stranded structure. The 2-5As in turn activate RNaseL that degrade single stranded RNAs.
View Article and Find Full Text PDFTCF3 (E2A) is a multifunctional basic helix loop helix (bHLH) transcription factor that is over-expressed in prostate cancer (PCa) as compared to normal prostate and that it acts as a tumor promoter in PCa. Given the diverse biological pathways regulated/influenced by TCF3, little is known about the mechanisms that regulate its expression. TCF3 expression in androgen sensitive LNCaP and insensitive C81 PCa cell lines was determined following treatments with androgen receptor (AR) agonist R1881 and antagonist Casodex.
View Article and Find Full Text PDFThe p53 protein is a stress response protein that functions primarily as a tetrameric transcription factor. A tumor suppressor p53 binds to a specific DNA sequence and transactivates target genes, leading to cell cycle apoptosis. Encoded by the human gene TP53, p53 is a stress response protein that functions primarily as a tetrameric transcription factor.
View Article and Find Full Text PDFDefined culture systems supporting spermatogonial differentiation will provide experimental platforms to study spermatogenesis. However, germline-intrinsic signaling mechanisms sufficient to support spermatogonial differentiation without somatic cells remain largely undefined. Here, we analyzed EGF superfamily receptor and ligand diversity in rat testis cells, and delineated germline-intrinsic signaling an ERBB3 co-transducer, ERBB2, as essential for retinoic acid-induced syncytial growth by differentiating spermatogonia.
View Article and Find Full Text PDFProstate cancer (PCa) disease progression is associated with significant changes in intracellular and extracellular proteins, intracellular signaling mechanism, and cancer cell phenotype. These changes may have direct impact on the cellular interactions with nanocarriers; hence, there is the need for a much-detailed understanding, as nanocarrier cellular internalization and intracellular sorting mechanism correlate directly with bioavailability and clinical efficacy. In this study, we report the differences in the rate and mechanism of cellular internalization of a biocompatible polycaprolactone (PCL)/maltodextrin (MD) nanocarrier system for intracellular drug delivery in LNCaP, PC3, and DU145 PCa cell lines.
View Article and Find Full Text PDFThe four known ID proteins (ID1-4, Inhibitor of Differentiation) share a homologous helix loop helix (HLH) domain and act as dominant negative regulators of basic-HLH transcription factors. ID proteins also interact with many non-bHLH proteins in complex networks. The expression of ID proteins is increasingly observed in many cancers.
View Article and Find Full Text PDFOrganisms with targeted genomic modifications are efficiently produced by gene editing in embryos using CRISPR/Cas9 RNA-guided DNA endonuclease. Here, to facilitate germline editing in rats, we used CRISPR/Cas9 to catalyze targeted genomic mutations in rat spermatogonial stem cell cultures. CRISPR/Cas9-modified spermatogonia regenerated spermatogenesis and displayed long-term sperm-forming potential following transplantation into rat testes.
View Article and Find Full Text PDFHighly conserved Inhibitors of DNA-Binding (ID1-ID4) genes encode multi-functional proteins whose transcriptional activity is based on dominant negative inhibition of basic helix-loop-helix (bHLH) transcription factors. Initial animal models indicated a degree of compensatory overlap between ID genes such that deletion of multiple ID genes was required to generate easily recognizable phenotypes. More recently, new model systems have revealed alterations in mice harboring deletions in single ID genes suggesting complex gene and tissue specific functions for members of the ID gene family.
View Article and Find Full Text PDFProstate cancer is a major health burden within the ever-increasingly aging US population. The molecular mechanisms involved in prostate cancer are diverse and heterogeneous. In this context, epigenetic changes, both global and gene specific, are now an emerging alternate mechanism in disease initiation and progression.
View Article and Find Full Text PDFBackground: The interferon inducible Myxovirus (influenza virus) resistance A (MxA) is considered as a key mediator of the interferon-induced antiviral response. Mx proteins contain the typical GTP-binding motif and show significant homology to dynamin family of GTPases. Strong interaction of MxA with tubulin suggests that Mx proteins could be involved in mitosis.
View Article and Find Full Text PDFInhibitor of DNA binding/differentiation protein 4 (ID4) is dominant negative helix loop helix transcriptional regulator is epigenetically silenced due to promoter hyper-methylation in many cancers including prostate. However, the underlying mechanism involved in epigenetic silencing of ID4 is not known. Here, we demonstrate that ID4 promoter methylation is initiated by EZH2 dependent tri-methylation of histone 3 at lysine 27 (H3K27me3).
View Article and Find Full Text PDFProstate cancer (PCa) is the most commonly diagnosed cancer in men in the Western world. The transition of androgen-dependent PCa to castration-resistant (CRPC) is a major clinical manifestation during disease progression and presents a therapeutic challenge. Our studies have shown that genetic ablation of inhibitor of differentiation 4 (Id4), a dominant-negative helix loop helix protein, in mice results in prostatic intraepithelial neoplasia lesions and decreased Nkx3.
View Article and Find Full Text PDFIn mammalian testes, "A-single" spermatogonia function as stem cells that sustain sperm production for fertilizing eggs. Yet, it is not understood how cellular niches regulate the developmental fate of A-single spermatogonia. Here, immunolabeling studies in rat testes define a novel population of ERBB3(+) germ cells as approximately 5% of total SNAP91(+) A-single spermatogonia along a spermatogenic wave.
View Article and Find Full Text PDF