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101.
Jundong Gu Yanjun Wen Siwei Zhu Feng Hua Hui Zhao Hongrui Xu Jiacong You Linlin Sun Weiqiang Wang Jun Chen Qinghua Zhou 《PloS one》2013,8(4)
Background
Aberrant methylation of CpG islands acquired in tumor cells in promoter regions plays an important role in carcinogenesis. Accumulated evidence demonstrates P16INK4a gene promoter hypermethylation is involved in non-small cell lung carcinoma (NSCLC), indicating it may be a potential biomarker for this disease. The aim of this study is to evaluate the frequency of P16INK4a gene promoter methylation between cancer tissue and autologous controls by summarizing published studies.Methods
By searching Medline, EMBSE and CNKI databases, the open published studies about P16INK4a gene promoter methylation and NSCLC were identified using a systematic search strategy. The pooled odds of P16INK4A promoter methylation in lung cancer tissue versus autologous controls were calculated by meta-analysis method.Results
Thirty-four studies, including 2 652 NSCLC patients with 5 175 samples were included in this meta-analysis. Generally, the frequency of P16INK4A promoter methylation ranged from 17% to 80% (median 44%) in the lung cancer tissue and 0 to 80% (median 15%) in the autologous controls, which indicated the methylation frequency in cancer tissue was much higher than that in autologous samples. We also find a strong and significant correlation between tumor tissue and autologous controls of P16INK4A promoter methylation frequency across studies (Correlation coefficient 0.71, 95% CI:0.51–0.83, P<0.0001). And the pooled odds ratio of P16INK4A promoter methylation in cancer tissue was 3.45 (95% CI: 2.63–4.54) compared to controls under random-effect model.Conclusion
Frequency of P16INK4a promoter methylation in cancer tissue was much higher than that in autologous controls, indicating promoter methylation plays an important role in carcinogenesis of the NSCLC. Strong and significant correlation between tumor tissue and autologous samples of P16INK4A promoter methylation demonstrated a promising biomarker for NSCLC. 相似文献102.
Jia Liu Feng-Yu Liu Zhi-Qian Tong Zhi-Hua Li Wen Chen Wen-Hong Luo Hui Li Hong-Jun Luo Yan Tang Jun-Min Tang Jie Cai Fei-Fei Liao You Wan 《PloS one》2013,8(3)
Background
Bone cancer pain seriously affects the quality of life of cancer patients. Our previous study found that endogenous formaldehyde was produced by cancer cells metastasized into bone marrows and played an important role in bone cancer pain. However, the mechanism of production of this endogenous formaldehyde by metastatic cancer cells was unknown in bone cancer pain rats. Lysine-specific demethylase 1 (LSD1) is one of the major enzymes catalyzing the production of formaldehyde. The expression of LSD1 and the concentration of formaldehyde were up-regulated in many high-risk tumors.Objective
This study aimed to investigate whether LSD1 in metastasized MRMT-1 breast cancer cells in bone marrows participated in the production of endogenous formaldehyde in bone cancer pain rats.Methodology/Principal Findings
Concentration of the endogenous formaldehyde was measured by high performance liquid chromatography (HPLC). Endogenous formaldehyde dramatically increased in cultured MRMT-1 breast cancer cells in vitro, in bone marrows and sera of bone cancer pain rats, in tumor tissues and sera of MRMT-1 subcutaneous vaccination model rats in vivo. Formaldehyde at a concentration as low as the above measured (3 mM) induced pain behaviors in normal rats. The expression of LSD1 which mainly located in nuclei of cancer cells significantly increased in bone marrows of bone cancer pain rats from 14 d to 21 d after inoculation. Furthermore, inhibition of LSD1 decreased the production of formaldehyde in MRMT-1 cells in vitro. Intraperitoneal injection of LSD1 inhibitor pargyline from 3 d to 14 d after inoculation of MRMT-1 cancer cells reduced bone cancer pain behaviors.Conclusion
Our data in the present study, combing our previous report, suggested that in the endogenous formaldehyde-induced pain in bone cancer pain rats, LSD1 in metastasized cancer cells contributed to the production of the endogenous formaldehyde. 相似文献103.
104.
So-Hee Lim Eunha Park Boram You Youngseob Jung A-Reum Park Sung Goo Park Jae-Ran Lee 《PloS one》2013,8(11)
Recently, it was found that microglia regulated synaptic remodeling of the developing brain, but their mechanisms have not been well understood. In this study, the action of microglia on neuronal synapse formation was investigated, and the primary target of microglial processes was discovered. When the developing microglia were applied to cultured hippocampal neurons without direct contact, the numbers of dendritic spines and excitatory and inhibitory synapses significantly increased. In order to find out the main factor for synaptic formation, the effects of cytokines released from microglia were examined. When recombinant proteins of cytokines were applied to neuronal culture media, interleukin 10 increased the numbers of dendritic spines in addition to excitatory and inhibitory synapses. Interestingly, without external stimuli, the amount of interleukin 10 released from the intact microglia appeared to be sufficient for the induction of synaptic formation. The neutralizing antibodies of interleukin 10 receptors attenuated the induction of the synaptic formation by microglia. The expression of interleukin 10 receptor was newly found in the hippocampal neurons of early developmental stage. When interleukin 10 receptors on the hippocampal neurons were knocked down with specific shRNA, the induction of synaptic formation by microglia and interleukin 10 disappeared. Pretreatment with lipopolysaccharide inhibited microglia from inducing synaptic formation, and interleukin 1β antagonized the induction of synaptic formation by interleukin 10. In conclusion, the developing microglia regulated synaptic functions and neuronal development through the interactions of the interleukin 10 released from the microglia with interleukin 10 receptors expressed on the hippocampal neurons. 相似文献
105.
Fei-Ying Yang Jun-Hui Chen Qian-Qian Ruan Hafiz S. A. Saqib Wei-Yi He Min-Sheng You 《Archives of insect biochemistry and physiology》2020,103(4):e21643
Mass spectrometry imaging (MSI) can visualize the composition, abundance, and spatial distribution of molecules in tissues or cells, which has been widely used in the research of life science. Insects, especially the agricultural pests, have received a great deal of interests from the scientists in biodiversity and food security. This review introduces the major characteristics of MSI, summarizes its application to the investigation of insect endogenous metabolites, exogenous metabolites, and the spatiotemporal changes of metabolites between insects and plants, and discusses its shortfalls and perspectives. The significance of these concerns is beneficial for future insect research such as physiology and metabolism. 相似文献
106.
Jiaqi You Kevin Mallery Douglas G. Mashek Mark Sanders Jiarong Hong Miki Hondzo 《Biotechnology and bioengineering》2020,117(4):i-i
Microalgae have been shown as a potential bioresource for food, biofuel, and pharmaceutical products. During the growth phases with corresponding environmental conditions, microalgae accumulate different amounts of various metabolites. We quantified the neutral lipids accumulation and analyzed the swimming signatures (speed and trajectories) of the motile green alga, Dunaliella primolecta, during the lag–exponential–stationary growth cycle at different nutrient concentrations. We discovered significant changes in the neutral lipid content and swimming signatures of microalgae across growth phases. The timing of the maximum swimming speed coincided with the maximum neutral lipid content and both maxima occurred under nutrient stress at the stationary growth phase. Furthermore, the swimming trajectories suggested statistically significant changes in swimming modes at the stationary growth phase when the maximum intracellular neutral lipid content was observed. Our results provide the potential exploitation of microalgal swimming signatures as possible indicators of the cultivation conditions and the timing of microalgal harvest to maximize the lipid yield for biofuel production. The findings can also be implemented to explore the production of food and antibiotics from other microalgal metabolites with low energy costs. 相似文献
107.
Daniel C. B. Jeffery Brandon A. Wyse Muhammad Attiq Rehman Geoffrey W. Brown Zhiying You Roxanne Oshidari Hisao Masai Krassimir Y. Yankulov 《Nucleic acids research》2013,41(18):8475-8488
Position-effect variegation (PEV) phenotypes are characterized by the robust multigenerational repression of a gene located at a certain locus (often called gene silencing) and occasional conversions to fully active state. Consequently, the active state then persists with occasional conversions to the repressed state. These effects are mediated by the establishment and maintenance of heterochromatin or euchromatin structures, respectively. In this study, we have addressed an important but often neglected aspect of PEV: the frequency of conversions at such loci. We have developed a model and have projected various PEV scenarios based on various rates of conversions. We have also enhanced two existing assays for gene silencing in Saccharomyces cerevisiae to measure the rate of switches from repressed to active state and vice versa. We tested the validity of our methodology in Δsir1 cells and in several mutants with defects in gene silencing. The assays have revealed that the histone chaperone Chromatin Assembly Factor I is involved in the control of epigenetic conversions. Together, our model and assays provide a comprehensive methodology for further investigation of epigenetic stability and position effects. 相似文献
108.
109.
Xiao‐Peng Zhang Tao Wu Jian Liu Jin‐Cheng Zhao Cheng‐Hui Li Xiao‐Zeng You 《Chirality》2013,25(7):384-392
Two couples of enantiomeric platinum(II) complexes: Pt(L1a)Cl ( 1a ), Pt(L1b)Cl ( 1b ) and Pt(L1a)(C ≡ C ? Ph) ( 2a ), Pt(L1b)(C ≡ C ? Ph) ( 2b ) (L1a = (+)‐1,3‐di‐(2‐(4,5‐pinene)pyridyl)benzene, L1b = (?)‐1,3‐di‐(2‐(4,5‐pinene)pyridyl)benzene) were synthesized and characterized. Their absolute configurations were determined by single crystal X‐ray diffraction and further verified by circular dichroism (CD) spectra (including electronic circular dichroism [ECD] and vibrational circular dichroism [VCD]). These complexes show interesting mechanoluminescence and/or vapoluminescence due to crystalline‐to‐amorphous transformation. The crystalline solids, grinding‐induced amorphous powders, and vapor‐induced amorphous powders of complexes 2a and 2b were comparatively investigated by solid‐state ECD and VCD spectra. The transformation from crystalline solids to amorphous powders was accompanied by significant variances of the spectral feature in both ECD and VCD spectra. Chirality 25:384–392, 2013. © 2013 Wiley Periodicals, Inc. 相似文献