Helicobacter pylori associated chronic gastritis,clinical syndromes,precancerous lesions,and pathogenesis of gastric cancer development

Helicobacter pylori (H. pylori) infection is well known to be associated with the development of precancerous lesions such as chronic atrophic gastritis (AG), or gastric intestinal metaplasia (GIM), and cancer. Various molecular alterations are identified not only in gastric cancer (GC) but also in precancerous lesions. H. pylori treatment seems to improve AG and GIM, but still remains controversial. In contrast, many studies, including meta-analysis, show that H. pylori eradication reduces GC. Molecular markers detected by genetic and epigenetic alterations related to carcinogenesis reverse following H. pylori eradication. This indicates that these changes may be an important factor in the identification of high risk patients for cancer development. Patients who underwent endoscopic treatment of GC are at high risk for development of metachronous GC. A randomized controlled trial from Japan concluded that prophylactic eradication of H. pylori after endoscopic resection should be used to prevent the development of metachronous GC, but recent retrospective studies did not show the tendency. Patients with precancerous lesions (molecular alterations) that do not reverse after H. pylori treatment, represent the “point of no return” and may be at high risk for the development of GC. Therefore, earlier H. pylori eradication should be considered for preventing GC development prior to the appearance of precancerous lesions.

The Differential Effects of Chronic Alcohol and Cigarette Smoke Exposures on Cognitive-Behavioral Dysfunction in Long Evans Rats

Background and Objective: Chronic heavy alcohol consumption and daily cigarette smoking are the most prevalent substance use problems in the U.S., including Veterans. Excessive alcohol use causes neurocognitive and behavioral deficits that can be linked to neurodegeneration. Similarly, preclinical and clinical data suggest that smoking also leads to brain atrophy. This study examines the differential and additive effects of alcohol and cigarette smoke (CS) exposures on cognitive-behavioral function. Methods: A 4-way experimental model of chronic alcohol and CS exposures was generated using 4-week-old male and female Long Evans rats that were pair-fed with Lieber-deCarli isocaloric liquid diets containing 0% or 24% ethanol for 9 weeks. Half of the rats in the control and ethanol groups were exposed to CS for 4 hours/day and 4 days/week for 9 weeks. All rats were subjected to Morris Water Maze, Open Field, and Novel Object Recognition testing in the last experimental week. Results: Chronic alcohol exposure impaired spatial learning as shown by significantly increased latency to locate the platform, and it caused anxiety-like behavior marked by the significantly reduced percentage of entries to the center of the arena. Chronic CS exposure impaired recognition memory as suggested by significantly less time spent at the novel object. Combined exposures to alcohol and CS did not show any significant additive or interactive effect on cognitive-behavioral function. Conclusion: Chronic alcohol exposure was the main driver of spatial learning, while the effect of secondhand CS exposure was not robust. Future studies need to mimic direct CS exposure effects in humans.

Insight into the biology of Macrophage Migration Inhibitory Factor （MIF） revealed by the cloning of its cell surface receptor

The recent cloning of MIF receptor fills an important gap in our understanding of the molecular biology and immunology of MIF. The MIF receptor, like MIF, does not fall into any established family of protein mediators, providing both new challenges and opportunities for the structural and functional analysis of MIF signal transduction.

Unintended targeting of Dmp1-Cre reveals a critical role for Bmpr1a signaling in the gastrointestinal mesenchyme of adult mice

Cre/loxP technology has been widely used to study cell type-specific functions of genes. Proper interpretation of such data critically depends on a clear understanding of the tissue specificity of Cre expression. The Dmpl- Cre mouse, expressing Cre from a 14-kb DNA fragment of the mouse Dmpl gene, has become a common tool for studying gene function in osteocytes, but the presumed cell specificity is yet to be fully established. By using the Ai9 reporter line that expresses a red fluorescent protein upon Cre recombination, we find that in 2-month-old mice, Dmpl-Cre targets not only osteocytes within the bone matrix but also osteoblasts on the bone surface and preosteoblasts at the metaphyseal chondro-osseous junction. In the bone marrow, Cre activity is evident in certain stromal cells adjacent to the blood vessels, but not in adipocytes. Outside the skeleton, Dmpl-Cre marks not only the skeletal muscle fibers, certain cells in the cerebellum and the hindbrain but also gastric and intestinal mesenchymal cells that express Pdgfra. Confirming the utility of Dmpl-Cre in the gastrointestinal mesenchyme, deletion of Bmprla with Dmpl-Cre causes numerous large polyps along the gastrointestinal tract, consistent with prior work involving inhibition of BMP signaling. Thus, caution needs to be exercised when using Dmpl-Cre because it targets not only the osteoblast lineage at an earlier stage than previously appreciated, but also a number of non-skeletal cell types.

Candida esophagitis:Risk factors in non-HIV population in Pakistan

AIM:Candida esophagitis is a frequent infection in immunocompromised patients. This study was designed to determine its characteristics in non- human immune deficiency virus (HIV) infected patients attending a teaching hospital.METHODS: Clinical records of all patients coded by international classification of diseases 9th revision with clinical modifications'(ICD-9-CM), with candida esophagitis diagnosed by esophagogastroduodenoscopy (EGD) and histopathology over a period of 5 years were studied.RESULTS: Fifty-one patients (27 males, 24 females, range 21-77 years old and mean age 52.9 years) fulfilled the criteria (0.34% of the EGD). The common predisposing factors were carcinoma (OR 3.87, CI 1.00-14.99) and diabetes mellitus (OR 4.39, CI 1.34-14.42). The frequent clinical symptoms were retrosternal discomfort, dysphagia and epigastric abdominal pain with endoscopic appearance of scattered mucosal plaques. Another endoscopic lesion was associated with candida esophagitis in 15% patients.CONCLUSION: Carcinomas, diabetes mellitus, corticosteroid and antibiotic therapy are major risk factors for candida esophagitis in Pakistan. It is an easily managed complication that responds to treatment with nystatin.

Requirement for cyclin D3 in germinal center formation and function

Germinal centers （GC） of secondary lymphoid tissues are critical to mounting a high-affinity humoral immune response. B cells within the GC undergo rapid clonal expansion and selection while diversifying their antibody genes. Although it is generally believed that GC B cells employ a unique proliferative program to accommodate these processes, little is known about how the GC-associated cell cycle is orchestrated. The D-type cyclins constitute an important component of the cell cycle engine that enables the cells to respond to physiological changes. Cell type- and developmental stage-specific roles of D-type cyclins have been described but the cyclin D requirement during GC reaction has not been addressed. In this study, we report that cyclin D3 is largely dispensable for proliferation and Ig class switching of in vitro activated B cells. In contrast, GC development in Ccnd3^-/- mice is markedly impaired, as is the T cell-dependent antibody response. Within the GC, although both switched and unswitched B cells are affected by cyclin D3 inactivation, the IgM^- pool is more severely reduced. Interestingly, despite a compensatory increase in cyclln D2 expression, a significant number of Ccnd3^-/- GC B cells accumulate in quiescent GO state. Lastly, although cyclin D3 inactivation did not disrupt BCL6 expression in GC B cells, it completely blocked the GC promoting effect of BCL6 overexpression, suggesting that cyclin D3 acts downstream of BCL6 to regulate GC formation. This is the first demonstration that cyclin D3 plays an important and unique role at the GC stage of B cell development.

Gastric atrophy,diagnosing and staging

Hpylori is now accepted as the cause of gastritis and gastritis-associated diseases, such as duodenal ulcer, gastric ulcer, gastric carcinoma, and gastric MALT lymphoma. The natural history of H pylori gastritis includes inflammation progressing from the antrum into the adjacent corpus resulting in an atrophic front of advancing injury leading to a reduction in acid secretion and eventual loss of parietal cells and development of atrophy. Sub-typing intestinal metaplasia has no clinical value to the patient, the pathologist, or the endoscopist. The pattern, extent, and severity of atrophy, with or without intestinal metaplasia, is a far more important predictor than is intestinal metaplasia subtype. The challenge remains to identify a reliable marker that relates to pre-malignant potential.

Advances and perspectives on cellular therapy in acquired bone marrow failure diseases

Acquired bone marrow failure diseases(ABMFD) are a class of hematopoietic stem cell diseases with a commonality of non-inherited disruption of hematopoiesis that results in pancytopenia. ABMFDs also are a group of heterogeneous diseases with different etiologies and treatment options. The three most common ABMFDs are aplastic anemia, myelodysplastic syndrome, and paroxysmal nocturnal hemoglobinuria. Stem cell transplantation is the only treatment that can cure these diseases. However, due to high therapy-related mortality, stem cell transplantation has rarely been used as a first line treatment in treating ABMFD. With the advance of personalized medicine and precision medicine, various novel cellular therapy strategies are in trial to increase the efficiency and efficacy of ABMFD treatment. This article aims to review current available stem cell transplantation protocols and promising cellular therapy research in treating ABMFD.

MicroRNA in TLR signaling and endotoxin tolerance

Toll-like receptors(TLRs)in innate immune cells are the prime cellular sensors for microbial components.TLR activation leads to the production of proinflammatory mediators and thus TLR signaling must be properly regulated by various mechanisms to maintain homeostasis.TLR4-ligand lipopolysaccharide(LPS)-induced tolerance or cross-tolerance is one such mechanism,and it plays an important role in innate immunity.Tolerance is established and sustained by the activity of the microRNA miR-146a,which is known to target key elements of the myeloid differentiation factor 88(MyD88)signaling pathway,including IL-1 receptor-associated kinase(IRAK1),IRAK2 and tumor-necrosis factor(TNF)receptor-associated factor 6(TRAF6).In this review,we comprehensively examine the TLR signaling involved in innate immunity,with special focus on LPS-induced tolerance.The function of TLR ligand-induced microRNAs,including miR-146a,miR-155 and miR-132,in regulating inflammatory mediators,and their impact on the immune system and human diseases,are discussed.Modulation of these microRNAs may affect TLR pathway activation and help to develop therapeutics against inflammatory diseases.

Nature:研究揭示lncRNA在调节细胞过程中发挥重要功能

在一项新的研究中。来自美国、日本和意大利的研究人员揭示出长链非编码RNA（IncRNA）可能在以一种组织特异性的方式控制细胞组分中发挥着至关重要的作用。这项新研究指出一种IncRNA在协助与肌肉再生和癌症相关的控制过程中发挥着关键性作用。

ZBTB7A governs estrogen receptor alpha expression in breast cancer

ZBTB7A, a member of the POZ/BTB and Krüppel （POK） family of transcription factors, has been shown to have a context-dependent role in cancer development and progression. The role of ZBTB7A in estrogen receptor alpha （ERα）-positive breast cancer is largely unknown. Approximately 70% of breast cancers are classified as ERα-positive. ERα carries out the biological effects of estrogen and its expression level dictates response to endocrine therapies and prognosis for breast cancer patients. In this study, we find that ZBTB7A transcriptionally regulates ERα expression in ERα-positive breast cancer cell lines by binding to the ESR1 promoter leading to increased transcription of ERα. Inhibition of ZBTB7A in ERα-positive cells results in decreased estrogen responsiveness as demonstrated by diminished estrogen-response element-driven luciferase reporter activity, induction of estrogen target genes, and estrogen-stimulated growth. We also report that ERα potentiates ZBTB7A expression via a post-translational mechanism, suggesting the presence of a positive feedback loop between ZBTB7A and ERα, conferring sensitivity to estrogen in breast cancer. Clinically, we find that ZBTB7A and ERα are often co-expressed in breast cancers and that high ZBTB7A expression correlates with improved overall and relapse-free survival for breast cancer patients. Importantly, high ZBTB7A expression predicts a more favorable outcome for patients treated with endocrine therapies. Together, these findings demonstrate that ZBTB7A contributes to the transcriptional program maintaining ERα expression and potentially an endocrine therapy-responsive phenotype in breast cancer.

Tackling heterogeneity in treatment-resistant breast cancer using a broad-spectrum therapeutic approach

Tumor heterogeneity can contribute to the development of therapeutic resistance in cancer, including advancedbreast cancers. The object of the Halifax project was to identify new treatments that would address mechanisms oftherapeutic resistance through tumor heterogeneity by uncovering combinations of therapeutics that could targetthe hallmarks of cancer rather than focusing on individual gene products. A taskforce of 180 cancer researchers,used molecular profiling to highlight key targets responsible for each of the hallmarks of cancer and then findexisting therapeutic agents that could be used to reach those targets with limited toxicity. In many cases, naturalhealth products and re-purposed pharmaceuticals were identified as potential agents. Hence, by combining themolecular profiling of tumors with therapeutics that target the hallmark features of cancer, the heterogeneity ofadvanced-stage breast cancers can be addressed.