Study of CRTC2 pharmacology using antisense oligonuceotides.

The cAMP response element binding protein (CREB)-regulated transcriptional coactivator 2 (CRTC2) is a key component of the transcription complex regulating glucagon driven hepatic glucose production and previous evidence suggests that "inhibition" of CRTC2 improves glucose homeostasis in multiple rodent models of type 2 diabetes. Here we describe a process of identifying potential therapeutic antisense oligonucleotides (ASOs) directed against CRTC2. These ASOs were designed as locked nucleic acid (LNA) gapmers and a panel of approximately 400 sequences were first screened in vitro within both human and mouse liver cell lines.

Chemical modification study of antisense gapmers.

A series of insertion patterns for chemically modified nucleotides [2'-O-methyl (2'-OMe), 2'-fluoro (2'-F), methoxyethyl (MOE), locked nucleic acid (LNA), and G-Clamp] within antisense gapmers is studied in vitro and in vivo in the context of the glucocorticoid receptor. Correlation between lipid transfection and unassisted (gymnotic--using no transfection agent) in vitro assays is seen to be dependent on the chemical modification, with the in vivo results corresponding to the unassisted assay in vitro. While in vitro mRNA knockdown assays are typically reasonable predictors of in vivo results, G-Clamp modified antisense oligonucleotides have poor in vivo mRNA knockdown as compared to transfected cell based assays.

Utility of a novel Oatp1b2 knockout mouse model for evaluating the role of Oatp1b2 in the hepatic uptake of model compounds.

We generated the organic anion transporting polypeptide (Oatp) 1b2 knockout (KO) mouse model and assessed its utility to study hepatic uptake using model compounds: cerivastatin, lovastatin acid, pravastatin, simvastatin acid, rifampicin, and rifamycin SV. A selective panel of liver cytochromes P450 (P450s) (Cyp3a11, Cyp3a13, Cyp3a16, Cyp2c29, and Cyp2c39) and transporters [Oatp1b2, Oatp1a1, Oatp1a4, Oatp1a5; organic anion transporter (Oat) 1, Oat2, Oat3; multidrug resistance gene 1 (Mdr1) a, Mdr1b; bile salt export pump, multidrug resistance associated protein (Mrp) 2, Mrp3; breast cancer resistance protein] were measured by reverse transcription-polymerase chain reaction in both KO and wild-type (WT) male mice. Male KO and WT mice received each model compound s.

Microarray analyses uncover UBE1L as a candidate target gene for lung cancer chemoprevention.

Retinoids, natural and synthetic derivatives of vitamin A, are active in cancer therapy and chemoprevention. We reported previously that all-trans-retinoic acid (RA) treatment prevented carcinogen-induced transformation of immortalized human bronchial epithelial (HBE) cells. To identify cancer chemopreventive mechanisms, immortalized (BEAS-2B), carcinogen-transformed (BEAS-2B(NNK)), and RA-chemoprevented (BEAS-2B(NNK/RA)) HBE cells were used to conduct microarray analyses independently.

Microarray analysis uncovers retinoid targets in human bronchial epithelial cells.

Retinoids, the natural and synthetic derivatives of vitamin A, have a role in cancer treatment and prevention. There is a need to reveal mechanisms that account for retinoid response or resistance. This study identified candidate all-trans-retinoic acid (RA) target genes linked to growth suppression in BEAS-2B human bronchial epithelial cells.