Anticancer activity of triterpene glycosides from the sea star Solaster pacificus.

Marine triterpene glycosides are known to exhibit significant anticancer activity. We investigated pacificusoside C and cucumariosides C and C isolated from a sea star Solaster pacificus in prostate cancer models with varying drug resistance and in non-cancerous cells in vitro. Cucumarioside C showed selectivity comparable to cisplatin, whereas the other compounds were less selective.

Liver-specific lncRNAs associated with liver cancers.

Long non-coding RNAs (lncRNAs) are transcripts with a length more than 200 nt, which do not encode proteins and act just as RNA molecules. In general, lncRNAs have much more distinct tissue specificity than proteins, as they usually realize more peculiar regulatory functions. Their expression levels are often altered in a response to stress conditions, metabolic changes, development of different diseases, and carcinogenesis.

Upregulation of long noncoding RNAs and is associated with intrahepatic cholangiocarcinoma.

ObjectiveMany long noncoding RNAs (lncRNAs) are associated with liver cancers, mainly hepatocellular carcinoma (HCC) and to a smaller extent intrahepatic cholangiocarcinoma (CCA). Most of such lncRNAs show similar dysregulation patterns when the two types of tumors are compared, suggesting that these aberrations are characteristic features of these liver tumor types. In the present study, we aimed to identify some candidate lncRNAs that are associated specifically with CCA.

Involvement of 6S RNA in Oxidative Stress Response.

6S RNA, a small non-coding RNA present in almost all bacteria, inhibits transcription via direct binding to RNA polymerase holoenzymes. The mechanism of 6S RNA action was investigated to a large extent in , however, lack of 6S RNA (Δ) was demonstrated to be unfavorable but not essential for cell survival under various growth conditions. In the present study, we revealed, for the first time, a lethal phenotype of the Δ strain in the presence of high concentrations of HO.

Northern Blot Detection of Tiny RNAs.

Successful detection of very small RNAs (tiny RNAs, ~8-15 nt in length) by northern blotting depends on tailored protocols with respect to transfer and immobilization on membranes as well as design of sensitive detection probes. For RNA crosslinking to positively charged membranes, we compared UV light with chemical RNA crosslinking by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), using either denaturing or native polyacrylamide gels. We show that northern blot detection of tiny RNAs with 5'-digoxigenin-labeled DNA/LNA mixmer probes is a highly sensitive and specific method and, in our hands, more sensitive than using a corresponding DNA/LNA mixmer probe with a 5'-P-end-label.

Discovery of Bivalent GalNAc-Conjugated Betulin as a Potent ASGPR-Directed Agent against Hepatocellular Carcinoma.

Herein, we describe the design, synthesis, and biological evaluation of novel betulin and -acetyl-d-galactosamine (GalNAc) glycoconjugates and suggest them as targeted agents against hepatocellular carcinoma. We prepared six conjugates derived via the C-3 and C-28 positions of betulin with one or two saccharide ligands. These molecules demonstrate high affinity to the asialoglycoprotein receptor (ASGPR) of hepatocytes assessed by in silico modeling and surface plasmon resonance tests.

New Small-Molecule Glycoconjugates of Docetaxel and GalNAc for Targeted Delivery to Hepatocellular Carcinoma.

In this work, we have developed covalent and low molecular weight docetaxel delivery systems based on conjugation with -acetyl-d-galactosamine and studied their properties related to hepatocellular carcinoma cells. The resulting glycoconjugates have an excellent affinity to the asialoglycoprotein receptor (ASGPR) in the nanomolar range of concentrations and a high cytotoxicity level comparable to docetaxel. Likewise, we observed the 21-75-fold increase in water solubility in comparison with parent docetaxel and prodrug lability to intracellular conditions with half-life values from 25.

Similarities and differences between 6S RNAs from Bradyrhizobium japonicum and Sinorhizobium meliloti.

6S RNA, a conserved and abundant small non-coding RNA found in most bacteria, regulates gene expression by inhibiting RNA polymerase (RNAP) holoenzyme. 6S RNAs from α-proteobacteria have been studied poorly so far. Here, we present a first in-depth analysis of 6S RNAs from two α-proteobacteria species, Bradyrhizobium japonicum and Sinorhizobium meliloti.

Panel of potential lncRNA biomarkers can distinguish various types of liver malignant and benign tumors.

Purpose: Liver cancers are among the deadliest malignancies due to a limited efficacy of early diagnostics, the lack of appropriate biomarkers and insufficient discrimination of different types of tumors by classic and molecular methods. In this study, we searched for novel long non-coding RNA (lncRNA) as well as validated several known candidates suitable as probable biomarkers for primary liver tumors of various etiology.

Methods: We described a novel lncRNA HELIS (aka "HEalthy LIver Specific") and estimated its expression by RT-qPCR in 82 paired tissue samples from patients with hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), combined HCC-CCA, pediatric hepatoblastoma (HBL) and non-malignant hepatocellular adenoma (HCA) and focal nodular hyperplasia (FNH).

Synthesis and Evaluation of New Trivalent Ligands for Hepatocyte Targeting via the Asialoglycoprotein Receptor.

Since the asialoglycoprotein receptor (also known as the "Ashwell-Morell receptor" or ASGPR) was discovered as the first cellular mammalian lectin, numerous drug delivery systems have been developed and several gene delivery systems associated with multivalent ligands for liver disease targeting are undergoing clinical trials. The success of these systems has facilitated the further study of new ligands with comparable or higher affinity and less synthetic complexity. Herein, we designed two novel trivalent ligands based on the esterification of tris(hydroxymethyl) aminomethane (TRIS) followed by the azide-alkyne Huisgen cycloaddition with azido -acetyl-d-galactosamine.

Improved Northern blot detection of small RNAs using EDC crosslinking and DNA/LNA probes.

Successful detection of very small RNAs (tiny RNA, ~14 nt in length) by Northern blotting is dependent on improved Northern blot protocols that combine chemical crosslinking of RNA with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) to positively charged membranes, the use of native polyacrylamide gels, and the development of highly sensitive and specific probes modified with locked nucleic acids (LNA). In this protocol, we show that Northern blot detection of tiny RNAs with 5'-digoxigenin-labeled DNA/LNA mixmer probes is a highly sensitive and specific method and, in our hands, more sensitive than using a corresponding DNA/LNA mixmer probe with a 5'-(32)P-end label.

Impact of RNA isolation protocols on RNA detection by Northern blotting.

We prepared total RNA from the Gram-positive soil bacterium Bacillus subtilis by different RNA extraction procedures to compare their suitability for Northern blot detection of tiny RNAs (~14-mers) or RNAs of intermediate size (100-200 nt) in terms of signal quality, intensity, and reproducibility. Our analysis included two hot phenol methods and two TRIzol extraction procedures. We found that signal intensity/detection sensitivity makes the key difference.

Phenotypic characterization and complementation analysis of Bacillus subtilis 6S RNA single and double deletion mutants.

6S RNA, a global regulator of transcription in bacteria, binds to housekeeping RNA polymerase (RNAP) holoenzymes to competitively inhibit transcription from DNA promoters. Bacillus subtilis encodes two 6S RNA homologs whose differential functions are as yet unclear. We constructed derivative strains of B.

Mechanistic comparison of Bacillus subtilis 6S-1 and 6S-2 RNAs--commonalities and differences.

Bacterial 6S RNAs bind to the housekeeping RNA polymerase (σ(A)-RNAP in Bacillus subtilis) to regulate transcription in a growth phase-dependent manner. B. subtilis expresses two 6S RNAs, 6S-1 and 6S-2 RNA, with different expression profiles.

In vivo and in vitro analysis of 6S RNA-templated short transcripts in Bacillus subtilis.

By differential high-throughput RNA sequencing (dRNA-seq) we have identified "product RNAs" (pRNAs) as short as 8-12 nucleotides that are synthesized by Bacillus subtilis RNA polymerase (RNAP) in vivo using the regulatory 6S-1 RNA as template. The dRNA-seq data were confirmed by in vitro transcription experiments and Northern blotting. In our libraries, we were unable to detect statistically meaningful numbers of reads potentially representing pRNAs derived from 6S-2 RNA.