Showing papers by "Thomas D. Schmittgen published in 2016"
TL;DR: A global increase in expression of T-UCRs is reported in both human and mouse PDAC, suggesting a similar mechanism of transcriptional upregulation for T- UCRs in PDAC.
Abstract: Transcribed ultraconserved regions (T-UCRs) are a class of non-coding RNAs with 100% sequence conservation among human, rat and mouse genomes. T-UCRs are differentially expressed in several cancers, however their expression in pancreatic adenocarcinoma (PDAC) has not been studied. We used a qPCR array to profile all 481 T-UCRs in pancreatic cancer specimens, pancreatic cancer cell lines, during experimental pancreatic desmoplasia and in the pancreases of P48Cre/wt; KrasLSL-G12D/wt mice. Fourteen, 57 and 29% of the detectable T-UCRs were differentially expressed in the cell lines, human tumors and transgenic mouse pancreases, respectively. The vast majority of the differentially expressed T-UCRs had increased expression in the cancer. T-UCRs were monitored using an in vitro model of the desmoplastic reaction. Twenty-five % of the expressed T-UCRs were increased in the HPDE cells cultured on PANC-1 cellular matrix. UC.190, UC.233 and UC.270 were increased in all three human data sets. siRNA knockdown of each of these three T-UCRs reduced the proliferation of MIA PaCa-2 cells up to 60%. The expression pattern among many T-UCRs in the human and mouse pancreases closely correlated with one another, suggesting that groups of T-UCRs are co-activated in PDAC. Successful knockout of the transcription factor EGR1 in PANC-1 cells caused a reduction in the expression of a subset of T-UCRs suggesting that EGR1 may control T-UCR expression in PDAC. We report a global increase in expression of T-UCRs in both human and mouse PDAC. Commonalties in their expression pattern suggest a similar mechanism of transcriptional upregulation for T-UCRs in PDAC.
39 citations
TL;DR: The results showed that position change of functional groups on lipid-like compounds can dramatically improve delivery efficiency, and optimized formulation ratios of TNT-b10 LLNs, a lead material, increasing delivery efficiency over 2-fold.
Abstract: Lipid-like nanoparticles (LLNs) have shown great potential for RNA delivery. Lipid-like compounds are key components in LLNs. In this study, we investigated the effects of local structural transformation of lipid-like compounds on delivery of messenger RNA. Our results showed that position change of functional groups on lipid-like compounds can dramatically improve delivery efficiency. We then optimized formulation ratios of TNT-b10 LLNs, a lead material, increasing delivery efficiency over 2-fold. More importantly, pegylated TNT-b10 LLNs is stable for over four weeks and is over 10-fold more efficient than that of its counterpart TNT-a10 LLNs. Additionally, the optimal formulation O-TNT-b10 LLNs is capable of delivering mRNA encoding luciferase in vivo. These results provide useful insights into the design of next generation LLNs for mRNA delivery.
38 citations
TL;DR: Examination of the mRNA and protein expression in pairs of primary HCC tumors and adjacent benign tissues showed that not only was CD151 mRNA andprotein increased in the tumors but also that an inverse correlation exists between the miR-199a-3p and CD151 RNA expression.
Abstract: Several studies have reported reduced miR-199a-3p expression in hepatocellular carcinoma (HCC). In an effort to discover important target genes for miR-199a-3p that may be related to HCC development or progression, we identified the tetraspanin, transmembrane glycoprotein CD151. Luciferase reporter assays and western blotting identified CD151 as a bona fide miR-199a-3p target gene. While CD151 protein was increased in the mesenchymal but not the epithelial HCC cell lines, CD151 knockdown with siRNA did not reduce HCC cell proliferation in either group of cells. miR-199a-3p reduced in vitro invasion and migration of CD151-positive HCC cells. Examination of the mRNA and protein expression in pairs of primary HCC tumors and adjacent benign tissues showed that not only was CD151 mRNA and protein increased in the tumors but also that an inverse correlation exists between the miR-199a-3p and CD151 RNA expression. We report that CD151 is a target of miR-199a-3p and that increased CD151 protein resulting from reduced miR-199a-3p could contribute to the development of metastatic HCC.
21 citations
TL;DR: It is suggested that, although HEK293T-derived EV are efficiently internalized by human monocytic cells, they do not exert a cytotoxic effect or alter phagocytic efficiency on the cell lines evaluated.
Abstract: The potential to engineer extracellular vesicles (EV) that target specific cells and deliver a therapeutic payload has propelled a growing interest in their development as promising therapeutics. These EV are often produced from cultured cells. Very little is known about the interaction of cell culture-derived EV with cells of the immune system and their potential immunomodulatory effects. The present study evaluated potential immunotoxic effects of HEK293T-derived EV on the human monocytic cell lines THP-1 and U937. Incubation of cells with different doses of EV for 16-24 h was followed by assessment of cytotoxicity and cell function by flow cytometry. Changes in cell functionality were evaluated by the capacity of cells to phagocytize fluorescent microspheres. In addition, the internalization of labeled EV in THP-1 and U937 cells was evaluated. Exposure to EV did not affect the viability of THP-1 or U937 cells. Although lower doses of the EV increased phagocytic capacity in both cell lines, phagocytic efficiency of individual cells was not affected by EV exposure at any of the doses evaluated. This study also demonstrated that THP-1 and U937 monocytic cells are highly permissive to EV entry in a dose-response manner. These results suggest that, although HEK293T-derived EV are efficiently internalized by human monocytic cells, they do not exert a cytotoxic effect or alter phagocytic efficiency on the cell lines evaluated.
14 citations