Radiation Induced Bystander Effect: From in Vitro Studies to Clinical Application

In the past 20 years, the classic paradigm in radiobiology recognizing DNA as the main target for the action of radiation has changed. The new paradigm assumes that both targeted and non-targeted effects of radiation determine the final outcome of irradiation. Radiotherapy is one of the main modality treatments of neoplastic diseases with intent to cure, or sometimes to palliate only, thus radiation-induced non-targeted effect, commonly referred to as the radiation-induced bystander effect (RIBE) may have a share in cancer treatment. RIBE is mediated by molecular signaling from radiation targeted cells to their non-irradiated neighbors, and comprises such phenomena as bystander effect, genomic instability, adaptive response and abscopal effect. Whereas first three phenomena may appear both in vitro and in vivo, an abscopal effect is closely related to partial body irradiation and is a systemic effect mediated by immunologic system which synergizes with radiotherapy. From the clinical point of view abscopal effect is particularly interesting due to both its possible valuable contribution to the treatment of metastases, and the potential harmful effects as induction of genetic instability and carcinogenesis. This review summarized the main results of investigations of non-targeted effects coming from in vitro monolayer cultures, 3-dimentional models of tissues, preclinical studies on rodents and clinically observed beneficial abscopal effects with particular emphasis on participation of immunotherapy in the creation of abscopal effects.

Methods for Detection of Viruses in Water and Wastewater

Viruses present in water might be harmful for human health and life. Nowadays over 100 pathogenic human virus species occur in water polluted with sewage. Chlorination, which is the most popular disinfection method is not able to remove easily viruses from treated water. Due to this, it’s necessary to detect viruses in water before treatment in order to determine disinfectant dose and to ensure the sanitary safety level of treated water. The aim of this article is to review viruses detection methods as well as the problems related to implementation of those methods in analysis of water and wastewater samples.

Targeted knockout of duox causes defects in zebrafish growth, thyroid development, and social interaction

Reactive oxygen species(ROS) are believed to be inevitable and toxic by-products produced during cellular respiration. However,several lines of evidence show that diverse extracellular signals can activate ROS production and provide important function for various biological processes.

Transformer2 proteins protect breast cancer cells from accumulating replication stress by ensuring productive splicing of checkpoint kinase 1

Increased expression levels of the RNA splicing regulator Transformer2fl （abbreviated Tra2fl） have been reported in several types of cancer. Recent work has revealed an intimate cross-regulation between Tra2fl and the highly similar Tra2a protein in human breast cancer cells, though these two proteins are encoded by separate genes created by a gene duplication that occurred over 500 million years ago. This cross-regulation involves splicing control of a special class of exons, called poison exons. Down-regulation of Tra2fl reduces splicing inclu- sion of a poison exon in the mRNA encoding Tra2a, thereby up-regulating Tra2a protein expression. This buffers any splicing changes that might be caused by individual depletion of Tra2fl alone. Discovery of this cross-regulation pathway, and its by-pass by joint deple- tion of both human Tra2 proteins, revealed Tra2 proteins are essential for breast cancer cell viability, and led to the identification of important targets for splicing control. These exons include a critical exon within the checkpoint kinase 1 （CHK1） gene that plays a crucial function in the protection of cancer cells from replication stress. Breast cancer cells depleted for Tra2 proteins have reduced CHK1 protein levels and accumulate DNA damage. These data suggest Tra2 proteins and/or their splicing targets as possible cancer drug targets.