The Sleeping Beauty (SB) transposon system mediates chromosomal integration and stable gene expression when an engineered SB transposon is delivered along with transposase. One concern in the therapeutic application of the SB system is that persistent expression of transposase could result in transposon instability and genotoxicity. Here, we tested the use of transposase-encoding RNA plus transposon DNA for correction of murine fumarylacetoacetate hydrolase (FAH) deficiency. A bi-functional transposon containing both mouse FAH and firefly luciferase sequences was used to track the growth of genetically corrected liver tissue by in vivo bioluminescence imaging after delivery of DNA or RNA as a source of transposase. Supplying SB transposase in the form of RNA resulted in selective repopulation of corrected hepatocytes with stable expression of FAH and luciferase. Plasma succinylacetone and amino acid levels were normalized, suggesting normal liver metabolism of catabolized protein products. Secondary FAH-deficient animals transplanted with hepatocytes (250,000) isolated from primary treated animals survived 2-(2-nitro-4-trifluoro-methylbenzoyl)-1,3-cyclohexanedione (NTBC) withdrawal, gained weight consistently, and demonstrated stable expression of luciferase. We conclude that transposase-encoding messenger RNA (mRNA) can be used to mediate stable non-viral gene therapy, resulting in complete phenotypic correction, and is thus an effective source of recombinase activity for use in human gene therapy.

Altered expression of miRNAs may contribute to multidrug resistance (MDR) in human cancers. This study investigated the association between miRNAs and MDR in five different drug-resistant hepatocellular carcinoma (HCC) cell sublines. The HCC Huh-7 cell line was treated with adramycin (ADM), cisplatin (DDP), carboplatin (CBP), mitomycin C (MMC) or vincristine (VCR) at increasing concentrations to develop drug-resistant sublines. The cell viability MTT assay was used to detect drug resistance. Five different drug-resistant HCC sublines, Huh-7/ADM, Huh-7/CBP, Huh-7/DDP, Huh-7/MMC and Huh-7/VCR, were established. Cells that were resistant to one drug were also found to be resistant to the other drugs. miRNA microarrays were analyzed to identify differential miRNA expression profiles in these cell lines, and real-time PCR was used to validate miRNA microarray data. miRNA microarray analysis showed that there were 53 upregulated miRNAs in Huh-7/ADM, 56 in Huh-7/CBP, 58 in Huh-7/DDP, 58 in Huh-7/MMC and 49 in Huh-7/VCR, whereas there were 52 downregulated miRNAs in Huh-7/ADM, 50 in Huh-7/CBP, 41 in Huh-7/DDP, 55 in Huh-7/MMC and 56 in Huh-7/VCR. Moreover, 26 simultaneously upregulated and 25 simultaneously downregulated miRNAs were noted in the Huh-7/ADM, Huh-7/CBP, Huh-7/DDP and Huh-7/MMC sublines compared to the parental Huh-7 cell line. In contrast, among these 51 upregulated and downregulated miRNAs, 12 miRNAs were upregulated and 13 miRNAs were downregulated in Huh-7/VCR. Upregulation of miR-27b, miR-181a, miR-146b-5p, miR-181d and miR-146a expression was verified using real-time RT-PCR in the parental and the five drug-resistant cell lines. In conclusion, the present study demonstrates that the differentially expressed miRNA profiles in these five drug-resistant HCC sublines could be useful to further investigate the association of miRNA expression with drug resistance in HCC.

Highlights Through unbiased kinome cDNA screening, we have identified creatine kinase brain-type (CKB) as a critical negative regulator of epithelial-mesenchymal transition . CKB is expressed significantly lower in tumors than in normal tissues and its downregulation correlates with poor prognosis in several solid cancer types. Its ectopic expression blocks, while its silencing promotes, AKT activation and prostate cancer progression. CKB physically sequestrates AKT from interacting with mTORC2 complex. We have also mapped the CKB and AKT interaction domains and further pinpointed a small fragment of 84aa on C-terminus of CKB protein as the key element in blocking AKT activation and Epithelial-mesenchymal transition.

Background G protein-coupled receptor (GPCR) is the most targeted protein family by the FDA-approved drugs. GPCR-kinase 3 (GRK3) is critical for GPCR signaling. Our genomic analysis showed that GRK3 expression correlated with poor prognosis of gastric adenocarcinoma (GAC) patients. However, GRK3’s functions and clinical utility in GAC progression and metastases are unknown. Methods We studied GRK3 expression in normal, primary, and metastatic GAC tissues. We identified a novel GRK3 inhibitor, LD2, through a chemical-library screen. Through genetic and pharmacologic modulations of GRK3, a series of functional and molecular studies were performed in vitro and in vivo. Impact of GRK3 on YAP1 and its targets was determined. Results GRK3 was overexpressed in GAC tissues compared to normal and was even higher in peritoneal metastases. Overexpression (OE) of GRK3 was significantly associated with shorter survival. Upregulation of GRK3 in GAC cells increased cell invasion, colony formation, and proportion of ALDH1+ cells, while its downregulation reduced these attributes. Further, LD2 potently and specifically inhibited GRK3, but not GRK2, a very similar kinase to GRK3. LD2 highly suppressed GAC cells’ malignant phenotypes in vitro. Mechanistically, GRK3 upregulated YAP1 in GAC tissues and its transcriptional downstream targets: SOX9, Birc5, Cyr61 and CTGF. Knockdown (KD) YAP1 rescued the phenotypes of GRK3 OE in GAC cells. GRK3 OE significantly increased tumor growth but LD2 inhibited tumor growth in the PDX model and dramatically suppressed peritoneal metastases induced by GRK3 OE. Conclusions GRK3, a poor prognosticator for survival, conferred aggressive phenotype. Genetic silencing of GRK3 or its inhibitor LD2 blunted GRK3-conferred malignant attributes, suggesting GRK3 as a novel therapeutic target in advanced GAC.