RNAi-mediated knockdown of cyclooxygenase2 inhibits the growth, invasion and migration of SaOS2 human osteosarcoma cells: a case control study

<p>Abstract</p> <p>Background</p> <p>Cyclooxygenase2 (COX-2), one isoform of cyclooxygenase proinflammatory enzymes, is responsible for tumor development, invasion and metastasis. Due to its role and frequent overexpression in a variety of human malignancies, including osteosarcoma, COX-2 has received considerable attention. However, the function of COX-2 in the pathogenesis of cancer is not well understood. We examined the role of COX-2 in osteosarcoma.</p> <p>Methods</p> <p>We employed lentivirus mediated-RNA interference technology to knockdown endogenous gene COX-2 expression in human osteosarcoma cells (SaOS2) and analyzed the phenotypical changes. The effect of COX-2 treatment on the proliferation, cell cycle, invasion and migration of the SaOS2 cells were assessed using the MTT, flow cytometry, invasion and migration assays, respectively. COX-2, vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), basic fibroblast growth factor (bFGF) mRNA and protein expression were detected by RT-PCR and western blotting.</p> <p>Results</p> <p>Our results indicate that a decrease of COX-2 expression in human osteosarcoma cells significantly inhibited the growth, decreased the invasion and migration ability of SaOS2 cells. In addition, it also reduced VEGF, EGF and bFGF mRNA and protein expression.</p> <p>Conclusions</p> <p>The COX-2 signaling pathway may provide a novel therapeutic target for the treatment of human osteosarcoma.</p

Second cancers and causes of death in patients with testicular cancer in Sweden

While treatment for testicular cancer (TC) has become standardized after the 1980s with an associated significant improvement in patient survival, this has been accompanied by an increased risk of second primary cancers (SPCs). Patients were identified from the Swedish Cancer Registry spanning the years from 1980 to 2015, including 8788 individuals with primary TC and their SPCs. Relative risks (RRs) for SPC were calculated using the generalized Poisson regression model. SPCs were diagnosed in 9.4% of patients with TC and half of them were late onset cancers not common in the population in their 40s. Overall RR of SPCs (excluding second TC) was 1.30 (95%CI: 1.20-1.40), including high risks for seven solid cancers, non-Hodgkin lymphoma and leukemia. Second TC was the most common SPC and the RR of 17.19 (95%CI: 14.89-19.85) was the highest recorded. Cancers known to be fatal as first primary cancers were also fatal as SPC in TC patients. Survival at 30 years of follow-up was approximately 80% for TC patients without SPC but it decreased to 40% for patients with SPC. The unexpected finding that half of the identified SPCs were typical late onset cancers in the middle-aged population raises concerns that therapy may facilitate premature aging. The risks of SPC are clinically important for the long-term management of TC patients and the high-mortality calls for a future management strategy.Peer reviewe

Comparison of Familial Clustering of Anogenital and Skin Cancers Between In Situ and Invasive Types

Literature on familial risk of carcinomas in situ (CISs) is limited because many cancer registries do not collect information on CIS. In Sweden CISs are collected, and we used these data to analyze familial relative risks (RRs) for concordant (CIS-CIS) types of anogenital (cervical, other female and male genital and anal) and skin squamous cell CIS; additionally RRs were assessed between CIS types and between CIS and invasive forms. RRs were calculated for the offspring generations when family members were diagnosed CIS. Case numbers for CIS ranged from 330 in anal to 177,285 in cervical CIS. Significant concordant CIS-CIS RRs were 2.74 for female genital, 1.77 for cervical and 2.29 for SCC skin CISs. The CIS forms associated also with each other, except for cervical and skin CIS types. RRs for concordant CIS-invasive cancer associations were lower than CIS-CIS associations. Cervical CIS associated with non-Hodgkin CIS which may suggest immune dysfunction as a contributing factors. The results for anogenital CIS types suggest that life style related human papilloma virus infections contributed to the observed familial associations. Lower risks for CIS-invasive cancer than CIS-CIS suggest that CIS and invasive cancers share only partially risk factors that underlie familial clustering.Peer reviewe

Familial Clustering, Second Primary Cancers and Causes of Death in Penile, Vulvar and Vaginal Cancers

Data on familial risks in penile and vulvar/vaginal cancers and in second primary cancers (SPCs) following these cancers are limited. We used the Swedish Family-Cancer Database from years 1958 through 2015 to identify 3641 penile and 8856 vulvar/vaginal cancers and to calculate relative risks (RRs) and 95% confidence intervals (CIs) for these cancers according to site-specific cancer in family members; additionally risk for SPCs was calculated. The familial RR for concordant (same) penile cancer was 3.22 (1.34-7.74), and it was 2.72 (1.69-4.39) for vulvar/vaginal cancer; RRs were increased for vulvar/vaginal cancer in families of anal cancer patients. RR for second penile cancer after penile cancers was 11.68 (7.95-17.18), while that for concordant vulvar/vaginal cancer was 9.03 (7.31-11.15). SPCs were diagnosed in 16.8% of penile cancer patients and in them 45.9% of deaths were caused by SPC (other than penile cancer). In vulvar/vaginal cancer patients with SPC, 36.4% of deaths were due to SPC. The results showed that these genital cancers might run in families and as SPCs are associated with human papilloma virus and smoking related cancers. Risk for these genital and anal SPCs are high and a follow-up plan should be agreed at diagnosis of these cancers.Peer reviewe

Spatially Resolved Correlation between Stiffness Increase and Actin Aggregation around Nanofibers Internalized in Living Macrophages

Plasticity and functional diversity of macrophages play an important role in resisting pathogens invasion, tumor progression and tissue repair. At present, nanodrug formulations are becoming increasingly important to induce and control the functional diversity of macrophages. In this framework, the internalization process of nanodrugs is co-regulated by a complex interplay of biochemistry, cell physiology and cell mechanics. From a biophysical perspective, little is known about cellular mechanics&rsquo; modulation induced by the nanodrug carrier&rsquo;s internalization. In this study, we used the polylactic-co-glycolic acid (PLGA)&ndash;polyethylene glycol (PEG) nanofibers as a model drug carrier, and we investigated their influence on macrophage mechanics. Interestingly, the nanofibers internalized in macrophages induced a local increase of stiffness detected by atomic force microscopy (AFM) nanomechanical investigation. Confocal laser scanning microscopy revealed a thickening of actin filaments around nanofibers during the internalization process. Following geometry and mechanical properties by AFM, indentation experiments are virtualized in a finite element model simulation. It turned out that it is necessary to include an additional actin wrapping layer around nanofiber in order to achieve similar reaction force of AFM experiments, consistent with confocal observation. The quantitative investigation of actin reconfiguration around internalized nanofibers can be exploited to develop novel strategies for drug delivery

Cells nanomechanics by atomic force microscopy: focus on interactions at nanoscale

Nanomechanics of cytoskeleton is deeply involved in physiology and regulation of cell behavior. Atomic Force Microscopy has been extensively used for quantitative characterization with high-spatial resolution, in particular showing tremendous opportunities in biomechanics by quantifying mechanical parameters related to cytoskeleton organization. In this short review, we highlight recent developments in cell nanomechanics by AFM focusing on methodology and direct application to investigate cytoskeleton restructuration when cells are interacting with nanostructures (surfaces and nanoparticles). In particular, cells can sense the stiffness of environment or internalized particles and AFM can detect the rearrangement of cytoskeleton as one of the responses of mechanotransduction stimuli. Current bottlenecks hindering further progress in technology, such as theoretical models of interpretation will be discussed, in particular we propose a solution for complex system by coupling AFM with finite element simulations to retrieve more quantitative information when heterogeneity and convolution play important roles. Finally, we present recent cutting-edge research directions to explore new techniques and enhance the capabilities of AFM nanomechanics for living cells

Spatial differences in East Asian climate transition at ∼260 ka and their links to ENSO

The East Asian summer precipitation exhibits significant spatial differences from inter-annual to sub-orbital timescales, which has been associated with El Niño-Southern Oscillation (ENSO). However, studies on spatial patterns of climate and their mechanisms on orbital and tectonic timescales are still scarce, impeding a better understanding of Asian monsoon dynamics on long timescales. Here, we present a loess section spanning the past 430 ka in the Menyuan (MY) basin from the Northeastern Tibetan Plateau (NETP), and compare it with records from other sites in East Asia in order to explore the spatial patterns of climate changes and their mechanisms. Our results reveal a distinct climate transition at ∼260 ka in various records, which is characterized a transition from a “wet–dry–wet” to a “dry–wet–dry” pattern in the north-south direction and a transition from a “dry–wet” to “wet–dry” pattern in the west-east direction. This climate transition coincides with a significant weakening of the equatorial Pacific zonal (east–west) thermal gradient which indicates a shift to a more El Niño-like state, suggesting that the climate transition in East Asia at ∼260 ka could be related to paleo-ENSO variation. A more El Niño-like state could force an intensification and southwestward extension of the Western Pacific Subtropical High (WPSH) which could in turn move the rainfall front westward with the maximum rainfall belt over central China, resulting in the persistence of the observed climate patterns in East Asia. Our model results suggest that the change of the paleo-ENSO condition at ∼260 ka could be related to the eccentricity-modulated insolation and the ice shelve changes in northern high latitudes. Our study highlights the important role of paleo-ENSO in regulating the long-term climate changes in different sub-regions in East Asia

Viral Abundance and Diversity of Production Fluids in Oil Reservoirs

Viruses are widely distributed in various ecosystems and have important impacts on microbial evolution, community structure and function and nutrient cycling in the environment. Viral abundance, diversity and distribution are important for a better understanding of ecosystem functioning and have often been investigated in marine, soil, and other environments. Though microbes have proven useful in oil recovery under extreme conditions, little is known about virus community dynamics in such systems. In this study, injection water and production fluids were sampled in two blocks of the Daqing oilfield limited company where water flooding and microbial flooding were continuously used to improve oil recovery. Virus-like particles (VLPs) and bacteria in these samples were extracted and enumerated with epifluorescence microscopy, and viromes of these samples were also sequenced with Illumina Hiseq PE150. The results showed that a large number of viruses existed in the oil reservoir, and VLPs abundance of production wells was 3.9 ± 0.7 × 108 mL−1 and virus to bacteria ratio (VBR) was 6.6 ± 1.1 during water flooding. Compared with water flooding, the production wells of microbial flooding had relative lower VLPs abundance (3.3 ± 0.3 × 108 mL−1) but higher VBR (7.9 ± 2.2). Assembled viral contigs were mapped to an in-house virus reference data separate from the GenBank non-redundant nucleotide (NT) database, and the sequences annotated as virus accounted for 35.34 and 55.04% of total sequences in samples of water flooding and microbial flooding, respectively. In water flooding, 7 and 6 viral families were identified in the injection and production wells, respectively. In microbial flooding, 6 viral families were identified in the injection and production wells. The total number of identified viral species in the injection well was higher than that in the production wells for both water flooding and microbial flooding. The Shannon diversity index was higher in the production well of water flooding than in the production well of microbial flooding. These results show that viruses are very abundant and diverse in the oil reservoir’s ecosystem, and future efforts are needed to reveal the potential function of viral communities in this extreme environment

A Machine‐Learning‐Based Bibliometric Analysis of Cell Membrane‐Coated Nanoparticles in Biomedical Applications over the Past Eleven Years

Abstract Cell membrane encapsulation is a growing concept in nanomedicine, for it achieves the purpose of camouflage nanoparticles, realizing the convenience for drug delivery, bio‐imaging, and detoxification. Cell membranes are constructed by bilayer lipid phospholipid layers, which have unique properties in cellular uptake mechanism, targeting ability, immunomodulation, and regeneration. Current medical applications of cell membranes include cancers, inflammations, regenerations, and so on. In this article, a general bibliometric overview is conducted of cell membrane‐coated nanoparticles covering 11 years of evolution in order to provide researchers in the field with a comprehensive view of the relevant achievements and trends. The authors analyze the data from Web of Science Core Collection database, and extract the annual publications and citations, most productive countries/regions, most influential scholars, the collaborations of journals and institutions. The authors also divided cell membranes into several subgroups to further understand the application of different cell membranes in medical scenarios. This study summarizes the current research overview in cell membrane‐coated nanoparticles and intuitively provides a direction for future research