Tracking bacterial DNA patterns in septic progression using 16s rRNA gene amplicon sequencing analysis

Bloodstream infections remain prevalent in intensive care units, leading to a public health challenge worldwide. Routine diagnosis is mainly based on blood culture, but the technique is limited by its time-consuming process and relatively low sensitivity. Emerging molecular diagnostic tools, such as 16S metagenomics, have been developed for detecting bacteria in the blood samples of septic patients. Using a collection of 168 blood samples from 96 septic patients, 16S metagenomics method followed by bioinformatics were applied to study bacterial alterations during the pathogenesis of sepsis. Significant taxonomic variations were found between the two survival groups at different therapeutic time points through sequential 16S metagenomics research. The results on the third day during the treatment course were notably distinct among the studied groups. 16S metagenomics approach can bring novel genetic insight about microbiological fluctuations during septic progression, which may be utilized as a complementary prognostic application. Further etiologic and pathophysiologic explorations are needed to fully explain the linkage between clinical outcomes and genetic changes.     

Significance of stratifin in early progression of lung adenocarcinoma and its potential therapeutic relevance

Lung cancer is the most common cause of global cancer-related mortality, and the main histological type is adenocarcinoma, accounting for 50% of non-small cell lung cancer. In 2015, the World Health Organization (WHO) histological classification defined the concepts of “adenocarcinoma in situ” (AIS) and “minimally invasive adenocarcinoma” (MIA), which are considered to be adenocarcinomas at a very early stage. Although AIS and MIA have a very favorable outcome, once they progress to early but invasive adenocarcinoma (eIA), they can sometimes have a fatal outcome. We previously compared the expression profiles of eIA and AIS, and identified stratifin (SFN; 14-3-3 sigma) as a protein showing significantly higher expression in eIA than in AIS. Expression of SFN is controlled epigenetically by DNA demethylation, and its overexpression is significantly correlated with poorer outcome. In vitro and in vivo analyses have shown that SFN facilitates early progression of adenocarcinoma by enhancing cell proliferation. This review summarizes genetic and epigenetic abnormalities that can occur in early-stage lung adenocarcinoma and introduces recent findings regarding the biological significance of SFN overexpression during the course of lung adenocarcinoma progression. Therapeutic strategies for targeting SFN are also discussed.     

The relationship of BRMS1 and RhoGDI2 gene expression to metastatic potential in lineage related human bladder cancer cell lines

We have recently characterized a human bladder cancer cell line T24 and a more aggressive lineage related variant of it, T24T. To gain further insights, we have studied their metastatic ability in an in vivo model system. Results show that T24 forms significantly fewer [4/12 (1/11) mice had metastases with 1-2 lesions/mouse] metastasis in SCID/bg mice than T24T [14/14 (6/6) mice had metastases with a mean of 24-28 lesions/mouse]. To begin exploring the mechanisms underlying this difference, we evaluated the mRNA and protein expression levels of metastasis-suppressor genes, known to be important in the progression of other cancers, in our model of bladder cancer progression. A higher mRNA expression of BRMS1, a metastasis suppressor in breast cancer, was observed in T24 cells. In addition, RhoGDI2 mRNA expression was only observed in T24 when compared to T24T, suggesting that Rho activation might play a significant role in the metastatic cascade. However, a basal level mRNA expression of KISS1, described as metastasis suppressor in melanoma and breast, was observed in both the lines and had slightly higher expression in T24T. No difference of Nm23-H1, KAI1, MKK4/SEK1 and E-Cadherin protein levels were noted between these two lines. In summary, it appears that the T24/T24T paired cell lines constitute a useful model for the study of human bladder cancer metastasis that will allow both the discovery and mechanistic evaluation of genes potentially involved in this process. This revised version was published online in July 2006 with corrections to the Cover Date.     

DEK expression in melanocytic lesions

The diagnosis of malignant melanoma presents a clinical challenge and relies principally on histopathological evaluation. Previous studies have indicated that increased expression of the DEK oncogene, a chromatin-bound factor, could contribute to the development of melanoma and may be a frequent event in melanoma progression. Here, we investigated DEK expression by immunohistochemistry in a total of 147 melanocytic lesions, including ordinary nevi, dysplastic nevi, Spitz nevi, melanoma in situ, primary invasive melanomas, and metastatic melanomas. Most benign nevi (ordinary, dysplastic, and Spitz nevi) were negative or exhibited weak staining for DEK, with only 4 of 49 cases showing strong staining. Similar to benign nevi, melanoma in situ also demonstrated low levels of DEK expression. In contrast, the expression of DEK in primary invasive melanomas was significantly higher than benign nevi (P < .0001). Moreover, DEK expression was significantly increased in deep melanomas (Breslow depth >1 mm) and metastatic melanomas as compared with superficial melanomas (Breslow depth ≤1 mm) (P < .05). Our findings indicate that DEK overexpression may be a frequent event in invasive melanomas, and further augmentation of DEK expression may be associated with the acquisition of ominous features such as deep dermal invasion and metastasis. These data suggest a role of DEK in melanoma progression.     

The sentinel role of the airway epithelium in asthma pathogenesis

The adoption of the concept that asthma is primarily a disease most frequently associated with elaboration of T-helper 2 (Th2)-type inflammation has led to the widely held concept that its origins, exacerbation, and persistence are allergen driven. Taking aside the asthma that is expressed in non-allergic individuals leaves the great proportion of asthma that is associated with allergy (or atopy) and that often has its onset in early childhood. Evidence is presented that asthma is primarily an epithelial disorder and that its origin as well as its clinical manifestations have more to do with altered epithelial physical and functional barrier properties than being purely linked to allergic pathways. In genetically susceptible individuals, impaired epithelial barrier function renders the airways vulnerable to early life virus infection, and this in turn provides the stimulus to prime immature dendritic cells toward directing a Th2 response and local allergen sensitization. Continued epithelial susceptibility to environmental insults such as viral, allergen, and pollutant exposure and impaired repair responses leads to asthma persistence and provides the mediator and growth factor microenvironment for persistence of inflammation and airway wall remodeling. Increased deposition of matrix in the epithelial lamina reticularis provides evidence for ongoing epithelial barrier dysfunction, while physical distortion of the epithelium consequent upon repeated bronchoconstriction provides additional stimuli for remodeling. This latter response initially serves a protective function but, if exaggerated, may lead to fixed airflow obstruction associated with more severe and chronic disease. Dual pathways in the origins, persistence, and progression of asthma help explain why anti-inflammatory treatments fail to influence the natural history of asthma in childhood and only partially does so in chronic severe disease. Positioning the airway epithelium as fundamental to the origins and persistence of asthma provides a rationale for pursuit of therapeutics that increase the resistance of the airways to environmental insults rather than concentrating all effort on suppressing inflammation.     

肿瘤相关巨噬细胞与肿瘤进展及治疗的关系

肿瘤微环境是一种复杂的细胞生态环境,肿瘤细胞与环境共同进化,环境为肿瘤细胞的恶性转变提供支持.在被招募到肿瘤位点的免疫细胞中,巨噬细胞的量最大,且贯穿肿瘤发生发展的各个阶段.动物实验及临床研究均表明巨噬细胞在肿瘤进展中发挥促进作用,并可作为肿瘤联合治疗中的有效靶点.     

Thymic pathogenicity of an HIV-1 envelope is associated with increased CXCR4 binding efficiency and V5-gp41-dependent activity, but not V1/V2-associated CD4 binding efficiency and viral entry

We previously described a thymus-tropic HIV-1 envelope (R3A Env) from a rapid progressor obtained at the time of transmission. An HIV-1 molecular recombinant with the R3A Env supported extensive replication and pathogenesis in the thymus and did not require Nef. Another Env from the same patient did not display the same thymus-tropic pathogenesis (R3B Env). Here, we show that relative to R3B Env, R3A Env enhances viral entry of T cells, increases fusion-induced cytopathicity, and shows elevated binding efficiency for both CD4 and CXCR4, but not CCR5, in vitro. We created chimeric envelopes to determine the region(s) responsible for each in vitro phenotype and for thymic pathogenesis. Surprisingly, while V1/V2 contributed to enhanced viral entry, CD4 binding efficiency, and cytopathicity in vitro, it made no contribution to thymic pathogenesis. Rather, CXCR4 binding efficiency and V5-gp41-associated activity appear to independently contribute to thymic pathogenesis of the R3A Env. These data highlight the contribution of unique HIV pathogenic factors in the thymic microenvironment and suggest that novel mechanisms may be involved in Env pathogenic activity in vivo.     

Case report of three EGFR TKI naïve lung adenocarcinoma containing double EGFR mutations (L858R/T790M or Exon 19 Deletion/T790M); Comparing genetic information and histology

EGFR T790M mutation is a crucial gene alteration causing EGFR TKI resistance. However, the implication of T790M mutation is still unknown for the stepwise progression of EGFR TKI naïve lung adenocarcinoma. In this study, we studied site-related EGFR T790M mutation analysis in EGFR TKI naïve lung adenocarcinomas harboring double EGFR mutation (L858R and T790M or Exon 19 deletion (Del.19) and T790M) by droplet digital (dd) PCR method. We examined three resected lung adenocarcinoma cases harboring EGFR double mutation including T790M. These cases didn’t receive EGFR TKI treatment. We divided formalin-fixed and paraffin embedded (FFPE) unstained slide tissues into 11–18 areas in each tumor and extracted DNAs from each area separately. The DNAs were analyzed by ddPCR. T790M mutation ratio (T790M/L858R or T790M/Del.19) were calculated. For three cases, we also performed EGFR FISH for analyzing EGFR copy number.In Case 2 and 3, T790M mutation ratio were 100% and 30% homogeneously and showed increased EGFR copy number also homogeneously. However, in case 1, it was different between invasive and non-invasive areas. EGFR copy number was also heterogeneous and showed increasing only in invasive area. We indicated a peculiar case harboring T790M heterogeneity and only invasive area had T790M mutation even though the case was not treated by EGFR TKI. It suggests that T790M is possibly significant not only for EGFR TKI resistance but also the progression in lung adenocarcinoma.