On dynamic network entropy in cancer

The cellular phenotype is described by a complex network of molecular interactions. Elucidating network properties that distinguish disease from the healthy cellular state is therefore of critical importance for gaining systems-level insights into disease mechanisms and ultimately for developing improved therapies. By integrating gene expression data with a protein interaction network to induce a stochastic dynamics on the network, we here demonstrate that cancer cells are characterised by an increase in the dynamic network entropy, compared to cells of normal physiology. Using a fundamental relation between the macroscopic resilience of a dynamical system and the uncertainty (entropy) in the underlying microscopic processes, we argue that cancer cells will be more robust to random gene perturbations. In addition, we formally demonstrate that gene expression differences between normal and cancer tissue are anticorrelated with local dynamic entropy changes, thus providing a systemic link between gene expression changes at the nodes and their local network dynamics. In particular, we also find that genes which drive cell-proliferation in cancer cells and which often encode oncogenes are associated with reductions in the dynamic network entropy. In summary, our results support the view that the observed increased robustness of cancer cells to perturbation and therapy may be due to an increase in the dynamic network entropy that allows cells to adapt to the new cellular stresses. Conversely, genes that exhibit local flux entropy decreases in cancer may render cancer cells more susceptible to targeted intervention and may therefore represent promising drug targets.Comment: 10 pages, 3 figures, 4 tables. Submitte

Non-emissive RuII Polypyridyl Complexes as Efficient and Selective Photosensitizers for the Photooxidation of Benzylamines

RTI2018-100709-B-C21 CTQ (QMC)-RED2018-102471-T) Junta de Castilla y Leon (BU087G19 FEDER (BU042U16-BU305P18).Five new RuII polypyridyl complexes bearing N-(arylsulfonyl)-8-amidoquinolate ligands and three of their biscyclometalated IrIII congeners have been prepared and employed as photocatalysts (PCs) in the photooxidation of benzylamines with O2. In particular, the new RuII complexes do not exhibit photoluminescence, rather they harvest visible light efficiently and are very stable in solution under irradiation with blue light. Their non-emissive behavior has been related to the low electrochemical energy gaps and rationalized on the basis of theoretical calculations (DFT analysis) that predict low S0←T1 energy values. Moreover, the RuII complexes, despite being non-emissive, display excellent activities in the selective photocatalytic transformation of benzylamines into the corresponding imines. The presence of an electron-withdrawing group (-CF3) on the arene ring of the N-(arylsulfonyl)-8-amidoquinolate ligand improves the photocatalytic activity of the corresponding photocatalyst. Furthermore, all the experimental evidence, including transient absorption spectroscopy measurements suggest that singlet oxygen is the actual oxidant. The IrIII analogues are considerably more photosensitive and consequently less efficient photosensitizers (PSs).authorsversionpublishe

Identification of DNA hypermethylation of SOX9 in association with bladder cancer progression using CpG microarrays

CpG island arrays represent a high-throughput epigenomic discovery platform to identify global disease-specific promoter hypermethylation candidates along bladder cancer progression. DNA obtained from 10 pairs of invasive bladder tumours were profiled vs their respective normal urothelium using differential methylation hybridisation on custom-made CpG arrays (n=12 288 clones). Promoter hypermethylation of 84 clones was simultaneously shown in at least 70% of the tumours. SOX9 was selected for further validation by bisulphite genomic sequencing and methylation-specific polymerase chain reaction in bladder cancer cells (n=11) and primary bladder tumours (n=101). Hypermethylation was observed in bladder cancer cells and associated with lack of gene expression, being restored in vitro by a demethylating agent. In primary bladder tumours, SOX9 hypermethylation was present in 56.4% of the cases. Moreover, SOX9 hypermethylation was significantly associated with tumour grade and overall survival. Thus, this high-throughput epigenomic strategy has served to identify novel hypermethylated candidates in bladder cancer. In vitro analyses supported the role of methylation in silencing SOX9 gene. The association of SOX9 hypermethylation with tumour progression and clinical outcome suggests its relevant clinical implications at stratifying patients affected with bladder cancer

Safety and Immunogenicity of Human Serum Albumin-Free MMR Vaccine in US Children Aged 12–15 Months

Background: M-M-RTMII (MMRII; Merck & Co) is currently the only measles-mumps-rubella (MMR) vaccine licensed in the United States. Another licensed vaccine would reinforce MMR supply. This study assessed the immunogenicity of a candidate vaccine (PriorixTM, GlaxoSmithKline Vaccines [MMR-RIT]) when used as a first dose among eligible children in the United States. Methods: In this exploratory Phase-2, multicenter, observer-blind study, 1220 healthy subjects aged 12–15 months were randomized (3:3:3:3) and received 1 dose of 1 of 3 MMR-RIT lots with differing mumps virus titers (MMR-RIT-1 [4.8 log10]; MMR-RIT-2 [4.1 log10]; MMR-RIT-3 [3.7 log10] CCID50) or MMRII co-administered with hepatitis Avaccine (HAV), varicella vaccine (VAR) and 7-valent pneumococcal conjugate vaccine (PCV7). Immune response to measles, mumps, and rubella viruses was evaluated at Day 42 post-vaccination. Incidence of solicited injection site, general, and serious adverse events was assessed. Results: Seroresponse rates for MMR vaccine viral components in MMR-RIT lots were 98.3–99.2% (measles), 89.7–90.7% (mumps), and 97.5–98.8% (rubella), and for MMRII were 99.6%, 91.1%, and 100%, respectively. Immune responses to HAV, VAR, and PCV7 were similar when co-administered with any of the 3MMR-RITlotsorMMRII.T here were no apparent differences in solicited or serious adverse events among the 4 groups. Conclusions: Immune responses were above threshold levels for projected protection against the 3 viruses from MMR-RIT lots with differing mumps virus titers. MMR-RIT had an acceptable safety profile when co-administered with HAV, VAR, and PCV7. Clinical Trials Registration. NCT00861744; etrack; 11187