Rewiring of master transcription factor cistromes during high-grade serous ovarian cancer development.

The transcription factors MECOM, PAX8, SOX17 and WT1 are candidate master regulators of high-grade serous 'ovarian' cancer (HGSC), yet their cooperative role in the hypothesized tissue of origin, the fallopian tube secretory epithelium (FTSEC) is unknown. We generated 26 epigenome (CUT&TAG, CUT&RUN, ATAC-seq and HiC) data sets and 24 profiles of RNA-seq transcription factor knock-down followed by RNA sequencing in FTSEC and HGSC models to define binding sites and gene sets regulated by these factors in cis and trans. This revealed that MECOM, PAX8, SOX17 and WT1 are lineage-enriched, super-enhancer associated master regulators whose cooperative DNA-binding patterns and target genes are re-wired during tumor development. All four TFs were indispensable for HGSC clonogenicity and survival but only depletion of PAX8 and WT1 impaired FTSEC cell survival. These four TFs were pharmacologically inhibited by transcriptional inhibitors only in HGSCs but not in FTSECs. Collectively, our data highlights that tumor-specific epigenetic remodeling is tightly related to MECOM, PAX8, SOX17 and WT1 activity and these transcription factors are targetable in a tumor-specific manner through transcriptional inhibitors.

The "Ins and Outs" of Prostate Specific Membrane Antigen (PSMA) as Specific Target in Prostate Cancer Therapy.

Prostate-specific membrane antigen (PSMA) is expressed in epithelial cells of the prostate gland and is strongly upregulated in prostatic adenocarcinoma, with elevated expression correlating with metastasis, progression, and androgen independence. Because of its specificity, PSMA is a major target of prostate cancer therapy; however, detectable levels of PSMA are also found in other tissues, especially in salivary glands and kidney, generating bystander damage of these tissues. Antibody target therapy has been used with relative success in reducing tumor growth and prostate specific antigen (PSA) levels. However, since antibodies are highly stable in plasma, they have prolonged time in circulation and accumulate in organs with an affinity for antibodies such as bone marrow. For that reason, a second generation of PSMA targeted therapeutic agents has been developed. Small molecules and minibodies have had promising clinical trial results, but concerns about their specificity had arisen with side effects due to accumulation in salivary glands and kidneys. Herein we study the specificity of small molecules and minibodies that are currently being clinically tested. We observed a high affinity of these molecules for PSMA in prostate, kidney and salivary gland, suggesting that their effect is not prostate specific. The search for specific prostate target agents must continue so as to optimally treat patients with prostate cancer, while minimizing deleterious effects in other PSMA expressing tissues.

Telomere Architecture Correlates with Aggressiveness in Multiple Myeloma.

The prognosis of multiple myeloma (MM), an incurable B-cell malignancy, has significantly improved through the introduction of novel therapeutic modalities. Myeloma prognosis is essentially determined by cytogenetics, both at diagnosis and at disease progression. However, for a large cohort of patients, cytogenetic analysis is not always available. In addition, myeloma patients with favorable cytogenetics can display an aggressive clinical course. Therefore, it is necessary to develop additional prognostic and predictive markers for this disease to allow for patient risk stratification and personalized clinical decision-making. Genomic instability is a prominent characteristic in MM, and we have previously shown that the three-dimensional (3D) nuclear organization of telomeres is a marker of both genomic instability and genetic heterogeneity in myeloma. In this study, we compared in a longitudinal prospective study blindly the 3D telomeric profiles from bone marrow samples of 214 initially treatment-naïve patients with either monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM), or MM, with a minimum follow-up of 5 years. Here, we report distinctive 3D telomeric profiles correlating with disease aggressiveness and patient response to treatment in MM patients, and also distinctive 3D telomeric profiles for disease progression in smoldering multiple myeloma patients. In particular, lower average intensity (telomere length, below 13,500 arbitrary units) and increased number of telomere aggregates are associated with shorter survival and could be used as a prognostic factor to identify high-risk SMM and MM patients.

p53 CRISPR Deletion Affects DNA Structure and Nuclear Architecture.

The TP53 gene is a key tumor suppressor. Although the tumor suppressor p53 was one of the first to be characterized as a transcription factor, with its main function potentiated by its interaction with DNA, there are still many unresolved questions about its mechanism of action. Here, we demonstrate a novel role for p53 in the maintenance of nuclear architecture of cells. Using three-dimensional (3D) imaging and spectral karyotyping, as well as super resolution microscopy of DNA structure, we observe significant differences in 3D telomere signatures, DNA structure and DNA-poor spaces as well gains or losses of chromosomes, between normal and tumor cells with CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-deleted or wild-type TP53. Additionally, treatment with Nutlin-3 results in differences in nuclear architecture of telomeres in wild-type but not in p53 knockout MCF-7 (Michigan Cancer Foundation-7) cells. Nutlin-3 binds to the p53-binding pocket of mouse double minute 2 (MDM2) and blocks the p53-MDM2 interaction. Moreover, we demonstrate that another p53 stabilizing small molecule, RITA (reactivation of p53 and induction of tumor cell apoptosis), also induces changes in 3D DNA structure, apparently in a p53 independent manner. These results implicate p53 activity in regulating nuclear organization and, additionally, highlight the divergent effects of the p53 targeting compounds Nutlin-3 and RITA.

Distinct Nuclear Organization of Telomeresand Centromeres in Monoclonal Gammopathyof Undetermined Significance and Multiple Myeloma.

Both multiple myeloma (MM) and its precursor state of monoclonal gammopathy of undetermined significance (MGUS) are characterized by an infiltration of plasma cells into the bone marrow, but the mechanisms underlying the disease progression remain poorly understood. Previous research has indicated that 3D nuclear telomeric and centromeric organization may represent important structural indicators for numerous malignancies. Here we corroborate with previously noted differences in the 3D telomeric architecture and report that modifications in the nuclear distribution of centromeres may serve as a novel structural marker with potential to distinguish MM from MGUS. Our findings improve the current characterization of the two disease stages, providing two structural indicators that may become altered in the progression of MGUS to MM.

Smart Sensing System for the Prognostic Monitoring of Bone Health.

The objective of this paper is to report a novel non-invasive, real-time, and label-free smart assay technique for the prognostic detection of bone loss by electrochemical impedance spectroscopy (EIS). The proposed system incorporated an antibody-antigen-based sensor functionalization to induce selectivity for the C-terminal telopeptide type one collagen (CTx-I) molecules-a bone loss biomarker. Streptavidin agarose was immobilized on the sensing area of a silicon substrate-based planar sensor, patterned with gold interdigital electrodes, to capture the antibody-antigen complex. Calibration experiments were conducted with various known CTx-I concentrations in a buffer solution to obtain a reference curve that was used to quantify the concentration of an analyte in the unknown serum samples. Multivariate chemometric analyses were done to determine the performance viability of the developed system. The analyses suggested that a frequency of 710 Hz is the most discriminating regarding the system sensitivity. A detection limit of 0.147 ng/mL was achieved for the proposed sensor and the corresponding reference curve was linear in the range of 0.147 ng/mL to 2.669 ng/mL. Two sheep blood samples were tested by the developed technique and the results were validated using enzyme-linked immunosorbent assay (ELISA). The results from the proposed technique match those from the ELISA.

Antimicrobial and immunomodulatory activities of an ovine proline/arginine-rich cathelicidin.

In in vitro co-culture experiments, the ovine-derived cathelicidin OaBac5mini showed antimicrobial activity against Escherichia coli cells and modulated production of a cytokine by a mammalian inflammatory cell type (macrophage). Using atomic force microscopy, the morphology of peptide-treated E. coli bacteria showed no cell lysis, indicating an intracellular mode of action of the peptide leading to bacterial cell inhibition. At a concentration of 50microg/mL OaBac5mini, the peptide suppressed production of the inflammatory cytokine interleukin-12 by murine J774A cells that had been stimulated with Staphylococcus aureus strain Cowan; levels of other cytokines were unaffected. Thus, certain cationic peptides can enter and disrupt invading Gram-negative pathogens and may be able to modulate inflammatory responses induced by Gram-positive bacterial products.

Identification of three novel ostricacins: an update on the phylogenetic perspective of beta-defensins.

Three new beta-defensins, ostricacins-2, 3 and 4 (Osp-2, 3 and 4), have been successfully purified and characterised from ostrich heterophils in addition to ostricacin-1 (Osp-1). These peptides are composed of 36-42 amino acids with a molecular weight range of 4.70-4.98 kDa. In vitro, Osp-1, 3 and 4 were active against Escherichia coli O157:H7 and Staphylococcus aureus 1056 MRSA, whilst Osp-2 was active against bacterial strains plus the yeast Candida albicans 3153A. Minimal inhibitory concentrations of the three ostricacins ranged from 0.96 microg/mL to 12.03 microg/mL. Comparison with the known beta-defensins from mammalian and other avian species revealed that the four ostricacins shared eight conserved residues (six cysteines and two glycines), identified as the 'beta-defensin core motif'. Comparisons of the sequence also indicated that beta-defensins could have originated from a common beta-defensin-like ancestor that occurred before avian and mammalian lines diverged.

Avian antimicrobial peptides: the defense role of beta-defensins.

Avian antimicrobial peptides, classified as beta-defensins, have been identified from bloods of chicken, turkey, and ostrich; epithelial cells of chicken and turkey; and king penguin stomach contents. Beta-defensins are a family of antimicrobial peptides characterized by six cysteine residues forming beta-defensin motifs that are also found in bovine, ovine, pig, and human. These peptides are active against a wide range of microorganisms including Gram-positive and Gram-negative bacteria, fungi, and yeast. Analysis of evolutionary relationships of vertebrate beta-defensins showed that there might be a common ancestral gene between avian and other mammalian peptides. This ancient gene may have been passed down and evolved from species older than the oldest living birds, forming a beta-defensin-like precursor molecule. This review describes potential applications of these peptides in health care products.