Knockdown of slincRAD leads to defective adipose development in vivo.

The development of adipose tissue is a precisely coordinated cellular process, in which both protein-coding and non-coding genes are involved. To characterize the in vivo function of a novel long non-coding RNA (lncRNAs), loss-of-function assays were performed with slincRAD knockdown mice. Down-regulation of slincRAD expression was found to impair the development of adipose tissue, leading to a slim phenotype for both of the male and female mice. Compared to normal adipocytes, slincRAD knockdown cells had defective differentiation features, such as smaller sizes and decreased lipid production. For elder mice, slincRAD knockdown led to abnormal glucose and lipid metabolism. Therefore, a physiologically important lncRNA was characterized in the development of adipose tissue.

siRNA Knockdown of RRM2 Effectively Suppressed Pancreatic Tumor Growth Alone or Synergistically with Doxorubicin.

Pancreatic cancer is currently one of the deadliest of the solid malignancies, whose incidence and death rates are increasing consistently during the past 30 years. Ribonucleotide reductase (RR) is a rate-limiting enzyme that catalyzes the formation of deoxyribonucleotides from ribonucleotides, which are essential for DNA synthesis and replication. In this study, 23 small interfering RNAs (siRNAs) against RRM2, the second subunit of RR, were designed and screened, and one of them (termed siRRM2), with high potency and good RNase-resistant capability, was selected. Transfection of siRRM2 into PANC-1, a pancreatic cell line, dramatically repressed the formation of cell colonies by inducing remarkable cell-cycle arrest at S-phase. When combining with doxorubicin (DOX), siRRM2 improved the efficacy 4 times more than applying DOX alone, suggesting a synergistic effect of siRRM2 and DOX. Moreover, the combined application of siRRM2-loaded lipid nanoparticle and DOX significantly suppressed the tumor growth on the PANC-1 xenografted murine model. The inhibition efficiency revealed by tumor weight at the endpoint of the treatment reached more than 40%. Hence, siRRM2 effectively suppressed pancreatic tumor growth alone or synergistically with DOX. This study provides a feasible target gene, a drug-viable siRNA, and a promising therapeutic potential for the treatment of pancreatic cancer.

The estrogenic potential of salicylate esters and their possible risks in foods and cosmetics.

Salicylate esters (SEs), a class of chemicals extensively used as flavor and fragrance additives in foods, beverages and a wide variety of consumer products, are suspected to have estrogenic activity based on chemical analysis of in silica molecular docking. We evaluated the estrogenic potentials of phenyl salicylate (PhS), benzyl salicylate (BzS), phenethyl salicylate (PES), ethyl salicylate (ES) and methyl salicylate (MS) using an in vitro human estrogen receptor α (hERα)-coactivator recruiting assay and in vivo immature rodent uterotrophic bioassays. We found that PhS, BzS and PES showed obvious in vitro hERα agonistic activities; BzS in particular exhibited a higher estrogenic activity compared to bisphenol A (BPA). The uterine weights were significantly increased in mice treated with 11.1, 33.3, 100 and 300 mg/kg/day BzS and 33.3mg/kg/day PES and rats treated with 3.7, 11.1, 33.3 and 100mg/kg/day BzS for 3 days (P<0.05). Finally, we transformed the daily intakes and the dermal exposures of SEs in the real world into estradiol equivalent concentrations (EEQs). We found that the EEQ of BzS daily intake in consumers in the U.S. and the EEQs of dermal BzS and PES exposure among high-volume users worldwide were higher than the maximum secure daily estradiol intake recommended by the U.S. Food and Drug Administration (FDA). In particular, the EEQ for dermal BzS exposure was up to 162 ng EEQ/kg, which is 3.3 times higher than the maximal acceptable daily E(2) intake recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA).

Estrogen agonist/antagonist properties of dibenzyl phthalate (DBzP) based on in vitro and in vivo assays.

The most commonly used phthalates have been banned or restricted for use as plasticizers in toys in some countries because of their endocrine-disrupting properties. Dibenzyl phthalate (DBzP) has been proposed as a possible alternative for the banned/restricted phthalates. In this study, the estrogen agonist/antagonist properties of DBzP were predicted by molecular docking and confirmed by yeast estrogen screen (YES) and immature mouse uterotrophic assays. The YES assay results showed a dose-dependent increase in DBzP estrogen agonist activity from 10⁻6 to 10⁻4 M, and at concentrations from 1.95×10⁻6 M to higher, DBzP significantly inhibited the agonist activity of 10⁻9 M 17ß-estradiol (E2), inhibiting 10⁻9 M E2 by 74.5% at its maximum effectiveness. The in vivo estrogen agonist/antagonist activities of DBzP were demonstrated in immature mouse uterotrophic assays. The antagonist activity of DBzP inhibited E2-induced uterine growth promoted at 40 and 400 µg/kg bw (body weight) (P<0.05). In addition, we also analyzed the estrogen agonist/antagonist potentials of benzyl butyl phthalate (BBP) by YES, and found both were weaker than those of DBzP, suggesting DBzP would be more toxic than BBP and should not be used as an alternative plasticizer.