Increased expression of long non-coding RNA XIST predicts favorable prognosis of cervical squamous cell carcinoma subsequent to definitive chemoradiation therapy

The present retrospective study aimed to examine the association between the expression of long non-protein-coding RNAs (lncRNAs) and clinical prognosis in the pretreatment formalin-fixed, paraffin-embedded (FFPE) tissue samples of cervical squamous cell carcinoma patients that underwent platinum-based chemoradiation therapy. Between 2001 and 2013, 49 consecutive patients with squamous cell cervical carcinoma were selected for the present study (median follow-up period, 44.1 months). The patients possessed an International Federation of Gynecology and Obstetrics stage of IB1/IIA1 (with pelvic lymph node metastasis), IB2 or IIA2-IVA, and had been treated with definitive chemoradiation therapy. The pretreatment FFPE tumor biopsies of the patients obtained diagnosis were used for analysis. Total RNAs were extracted from the FFPE tumor tissues and reverse transcription-quantitative polymerase chain reaction was performed to examine the expression level of lncRNAs. The expression level of X inactive-specific transcript (XIST) demonstrated a significant association with the overall survival rate (P=0.014). The 4-year overall survival rates were 87.1 and 54.4% in the high and low XIST expression groups, respectively. Since the expression of XIST is associated with the overall survival rate, this lncRNA has the potential to become a predictor for the prognosis of cervical squamous cell carcinoma patients that are treated with chemoradiation therapy. Additional studies are required to investigate the underlying mechanisms of XIST that are associated with prognosis.

A report that Fukushima residents are concerned about radiation from Land, Food and Radon

The Great East Japan Earthquake and subsequent TEPCO Fukushima Daiichi nuclear disaster occurred on 11 March 2011, which caused the leakage of radioactive materials into the environment. In this study, we report public concerns about radiation in Fukushima and Tokyo almost one year after the nuclear disaster. We examined the public concerns by analyzing the data from 1022 participants, 555 in Fukushima and 467 in Tokyo. They were asked whether they were concerned about radiation from some of six different types of sources, which could be answered in a binary way, 'yes' or 'no'. We found not only similarities, but also significant differences in the degrees of concerns between Fukushima residents and Tokyo ones. Fukushima residents more concerned about radiation from land, food and radon in larger rate than that of Tokyo ones, while Tokyo residents were concerned about radiation from medical care. Residents in neither location were concerned about radiation from space. Our results suggested that careful risk communication should be undertaken, adaptively organized depending on location and other factors, e.g. comprehension about radiation, presence of the experience of evacuation, and also age and gender of the people.

External effective radiation dose to workers in the restricted area of the Fukushima Daiichi Nuclear Power Plant during the third year after the Great East Japan Earthquake

Since the Great East Japan Earthquake on 11 March 2011, Iitate Village has continued to be classified as a deliberate evacuation area, in which residents are estimated to receive an annual additional effective radiation dose of >20 mSv. Some companies still operate in Iitate Village, with a special permit from the Cabinet Office Team in Charge of Assisting the Lives of Disaster Victims. In this study, we measured the annual effective radiation dose to workers in Iitate Village from 15 January to 13 December 2013. The workers stayed in Iitate for 10 h and left the village for the remaining 14 h each working day. They worked for 5 days each week in Iitate Village, but stayed outside of the village for the remaining 2 days each week. We found that the effective radiation dose of 70% of the workers was <2 mSv, including natural radiation; the maximum dose was 3.6 mSv. We estimated the potential annual additional effective radiation dose if people returned full-time to Iitate. Our analysis supports the plan for people to return to their home village at the end of 2017.

Degradation of initiator tRNAMet by Xrn1/2 via its accumulation in the nucleus of heat-treated HeLa cells

Stress response mechanisms that modulate the dynamics of tRNA degradation and accumulation from the cytoplasm to the nucleus have been studied in yeast, the rat hepatoma and human cells. In the current study, we investigated tRNA degradation and accumulation in HeLa cells under various forms of stress. We found that initiator tRNA^Met (tRNA(iMet)) was specifically degraded under heat stress. Two exonucleases, Xrn1 and Xrn2, are involved in the degradation of tRNA(iMet) in the cytoplasm and the nucleus, respectively. In addition to degradation, we observed accumulation of tRNA(iMet) in the nucleus. We also found that the mammalian target of rapamycin (mTOR), which regulates tRNA trafficking in yeast, is partially phosphorylated at Ser2448 in the presence of rapamycin and/or during heat stress. Our results suggest phosphorylation of mTOR may correlate with accumulation of tRNA(iMet) in heat-treated HeLa cells.

Identification of cis- and trans-acting factors involved in the localization of MALAT-1 noncoding RNA to nuclear speckles

MALAT-1 noncoding RNA is localized to nuclear speckles despite its mRNA-like characteristics. Here, we report the identification of several key factors that promote the localization of MALAT-1 to nuclear speckles and also provide evidence that MALAT-1 is involved in the regulation of gene expression. Heterokaryon assays revealed that MALAT-1 does not shuttle between the nucleus and cytoplasm. RNAi-mediated repression of the nuclear speckle proteins, RNPS1, SRm160, or IBP160, which are well-known mRNA processing factors, resulted in the diffusion of MALAT-1 to the nucleoplasm. We demonstrated that MALAT-1 contains two distinct elements directing transcripts to nuclear speckles, which were also capable of binding to RNPS1 in vitro. Depletion of MALAT-1 represses the expression of several genes. Taken together, our results suggest that RNPS1, SRm160, and IBP160 contribute to the localization of MALAT-1 to nuclear speckles, where MALAT-1 could be involved in regulating gene expression.

Formation of tRNA granules in the nucleus of heat-induced human cells

The stress response, which can trigger various physiological phenomena, is important for living organisms. For instance, a number of stress-induced granules such as P-body and stress granule have been identified. These granules are formed in the cytoplasm under stress conditions and are associated with translational inhibition and mRNA decay. In the nucleus, there is a focus named nuclear stress body (nSB) that distinguishes these structures from cytoplasmic stress granules. Many splicing factors and long non-coding RNA species localize in nSBs as a result of stress. Indeed, tRNAs respond to several kinds of stress such as heat, oxidation or starvation. Although nuclear accumulation of tRNAs occurs in starved Saccharomyces cerevisiae, this phenomenon is not found in mammalian cells. We observed that initiator tRNA(Met) (Meti) is actively translocated into the nucleus of human cells under heat stress. During this study, we identified unique granules of Meti that overlapped with nSBs. Similarly, elongator tRNA(Met) was translocated into the nucleus and formed granules during heat stress. Formation of tRNA granules is closely related to the translocation ratio. Then, all tRNAs may form the specific granules.

Method for the preparation of restricted access media by low-temperature plasma treatment

A new method for the preparation of restricted access media (RAM) was developed. A low-temperature plasma treatment removed octadecyl groups on the external surface of octadecylsilylated silica gel before those on the internal surface to produce silanol groups. The silanol groups produced were glycerylpropylsilylated to give RAM, DIOL-ODSs, consisting of internal octadecyl groups and external glycerylpropyl groups. DIOL-ODSs were inert to serum proteins and retained low-molecular-mass analytes adequately. Direct injection analysis of anticonvulsants in serum was accurately performed by column-switching high-performance liquid chromatography using a pre-column packed with DIOL-ODS.