Dataset Information

MicroRNA controlled adenovirus mediates anti-cancer efficacy without affecting endogenous microRNA activity.

ABSTRACT: MicroRNAs are small non-coding RNA molecules that regulate mRNA translation and stability by binding to complementary sequences usually within the 3' un-translated region (UTR). We have previously shown that the hepatic toxicity caused by wild-type Adenovirus 5 (Ad5WT) in mice can be prevented by incorporating 4 binding sites for the liver-specific microRNA, mir122, into the 3' UTR of E1A mRNA. This virus, termed Ad5mir122, is a promising virotherapy candidate and causes no obvious liver pathology. Herein we show that Ad5mir122 maintains wild-type lytic activity in cancer cells not expressing mir122 and assess any effects of possible mir122 depletion in host cells. Repeat administration of 2×10(10) viral particles of Admir122 to HepG2 tumour bearing mice showed significant anti-cancer efficacy. RT-QPCR showed that E1A mRNA was down-regulated 29-fold in liver when compared to Ad5WT. Western blot for E1A confirmed that all protein variants were knocked down. RT-QPCR for mature mir122 in infected livers showed that quantity of mir122 remained unaffected. Genome wide mRNA microarray profiling of infected livers showed that although the transcript level of >3900 different mRNAs changed more than 2-fold following Ad5WT infection, less than 600 were changed by Ad5mir122. These were then filtered to select mRNAs that were only altered by Ad5mir122 and the remaining 21 mRNAs were compared to predicted mir122 targets. No mir122 target mRNAs were affected by Ad5 mir122. These results demonstrate that the exploitation of microRNA regulation to control virus replication does not necessarily affect the level of the microRNA or the endogenous mRNA targets.

SUBMITTER: Cawood R

PROVIDER: S-EPMC3018484 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

MicroRNA controlled adenovirus mediates anti-cancer efficacy without affecting endogenous microRNA activity.

Cawood Ryan R Wong Suet-Ling SL Di Ying Y Baban Dilair F DF Seymour Leonard W LW

PloS one 20110110 1

MicroRNAs are small non-coding RNA molecules that regulate mRNA translation and stability by binding to complementary sequences usually within the 3' un-translated region (UTR). We have previously shown that the hepatic toxicity caused by wild-type Adenovirus 5 (Ad5WT) in mice can be prevented by incorporating 4 binding sites for the liver-specific microRNA, mir122, into the 3' UTR of E1A mRNA. This virus, termed Ad5mir122, is a promising virotherapy candidate and causes no obvious liver patholo ...[more]

PMID: 21264344

Similar Datasets

Project description:Replicating viruses have broad applications in biomedicine, notably in cancer virotherapy and in the design of attenuated vaccines, however uncontrolled virus replication in vulnerable tissues can give pathology and often restricts the use of potent strains. Increased knowledge of tissue-selective microRNA expression now affords the possibility of engineering replicating viruses that are attenuated at the RNA level in sites of potential pathology, but retain wild type replication activity at sites not expressing the relevant microRNA. To assess the usefulness of this approach for the DNA virus, adenovirus, we have engineered a hepatocyte-safe wild type adenovirus 5 (Ad5), which normally mediates significant toxicity and is potentially lethal in mice. To do this we have included binding sites for hepatocyte-selective microRNA122a within the 3' UTR of the E1A transcription cassette. Imaging versions of these viruses, produced by fusing E1A with luciferase, showed that inclusion of microRNA122a binding sites caused up to 80 fold decreased hepatic expression of E1A following intravenous delivery to mice. Animals administered a ten-times lethal dose of wild type Ad5 (5 x 1010 viral particles/mouse) showed substantial hepatic genome replication and extensive liver pathology, while inclusion of 4 microRNA binding sites decreased replication 50-fold and virtually abrogated liver toxicity. This modified wild type virus retained full activity within cancer cells and provides a potent, liver-safe oncolytic virus. In addition to providing many potent new viruses for cancer virotherapy, microRNA-control of virus replication should provide a new strategy for designing safe attenuated vaccines applied across a broad range of viral diseases. four groups which we had were: WT: RNA extracted from livers of mice treated with wild type Ad5, 3 Replicates miR: RNA extracted from livers of mice treated with wild type Ad5 bearing mir122-binding sites in the 3'UTR of E1A (3 Replicates) Luc: RNA extracted from livers of mice treated with non-replicating Ad5 (3 Replicates) PBS: RNA extracted from livers of mice treated with PBS only (3 Replicates)

Project description:BackgroundSkeletal muscle wasting and fatigue are commonly observed in cancer patients receiving chemotherapy and associated with reduced treatment outcome and quality of life. Nutritional support may mitigate these side effects, but potential interference with chemotherapy efficacy could be of concern. Here, we investigated the effects of an ω-3 polyunsaturated fatty acid (eicosapentaenoic acid and docosahexaenoic acid), leucine-enriched, high-protein (100% whey), additional vitamin D, and prebiotic fibres 'specific nutritional composition' (SNC) and chemotherapy on state-of-the-art tumour organoids and muscle cells and studied muscle function, physical activity, systemic inflammation, and chemotherapy efficacy in a mouse model of aggressive colorectal cancer (CRC).MethodsTumour-bearing mice received a diet with or without SNC. Chemotherapy treatment consisted of oxaliplatin and 5-fluorouracil. Tumour formation was monitored by calliper measurements. Physical activity was continuously monitored by infrared imaging. Ex vivo muscle performance was determined by myography, muscle fatty acid composition by gas chromatography, and plasma cytokine levels by Luminex xMAP technology. Patient-derived CRC organoids and C2C12 myotubes were used to determine whether SNC affects chemotherapy sensitivity in vitro.ResultsSpecific nutritional composition increased muscle contraction capacity of chemotherapy-treated tumour-bearing mice (P < 0.05) and enriched ω-3 fatty acid composition in muscle without affecting treatment efficacy (P < 0.0001). Mice receiving SNC maintained physical activity after chemotherapy and showed decreased systemic inflammation. Therapeutic response of CRC organoids was unaffected by SNC nutrients, while cell viability and protein synthesis of muscle cells significantly improved.ConclusionsThe results show that specialized nutritional support can be used to maintain muscle function and physical activity levels during chemotherapy without increasing tumour viability. Therefore, nutritional strategies have potential value in promoting cancer and chemotherapy tolerance.

Dataset Information

MicroRNA controlled adenovirus mediates anti-cancer efficacy without affecting endogenous microRNA activity.

Publications

MicroRNA controlled adenovirus mediates anti-cancer efficacy without affecting endogenous microRNA activity.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets