Chytrid infections exhibit historical spread and contemporary seasonality in a declining stream-breeding frog.

Species with extensive geographical ranges pose special challenges to assessing drivers of wildlife disease, necessitating collaborative and large-scale analyses. The imperilled foothill yellow-legged frog (Rana boylii) inhabits a wide geographical range and variable conditions in rivers of California and Oregon (USA), and is considered threatened by the pathogen Batrachochytrium dendrobatidis (Bd). To assess drivers of Bd infections over time and space, we compiled over 2000 datapoints from R. boylii museum specimens (collected 1897-2005) and field samples (2005-2021) spanning 9° of latitude. We observed a south-to-north spread of Bd detections beginning in the 1940s and increase in prevalence from the 1940s to 1970s, coinciding with extirpation from southern latitudes. We detected eight high-prevalence geographical clusters through time that span the species' geographical range. Field-sampled male R. boylii exhibited the highest prevalence, and juveniles sampled in autumn exhibited the highest loads. Bd infection risk was highest in lower elevation rain-dominated watersheds, and with cool temperatures and low stream-flow conditions at the end of the dry season. Through a holistic assessment of relationships between infection risk, geographical context and time, we identify the locations and time periods where Bd mitigation and monitoring will be critical for conservation of this imperilled species.

Why Turner patients with 45, X monosomy should not be excluded from fertility preservation services.

In this case report, we highlight the practical dilemma, i.e. to perform ovarian tissue cryopreservation surgery in a 45, X Turner Syndrome patient or not, by reporting on the presence of follicles in a 13-year-old female diagnosed with 45, X monosomy and an unmeasurable anti-müllerian hormone serum level. We compare our results with previous research, highlight the challenges we faced in this case and provide recommendations for daily practice. Hereby, we demonstrate that excluding certain subgroups of Turner Syndrome patients (e.g. monosomy patients, and/or girls with an anti-müllerian hormone level below 2.0 ng/l) may be premature, especially based on the current state of published research data. This practical example of a challenging dilemma in the counselling of Turner Syndrome patients for fertility preservation is of interest for clinicians involved in fertility counselling and Turner Syndrome care.

International consensus: ovarian tissue cryopreservation in young Turner syndrome patients: outcomes of an ethical Delphi study including 55 experts from 16 different countries.

STUDY QUESTION: What is the standpoint of an international expert panel on ovarian tissue cryopreservation (OTC) in young females with Turner syndrome (TS)? SUMMARY ANSWER: The expert panel states that OTC should be offered to young females with TS, but under strict conditions only. WHAT IS KNOWN ALREADY: OTC is already an option for preserving the fertility of young females at risk of iatrogenic primary ovarian insufficiency (POI). Offering OTC to females with a genetic cause of POI could be the next step. One of the most common genetic disorders related to POI is TS. Due to an early depletion of the ovarian reserve, most females with TS are confronted with infertility before reaching adulthood. However, before offering OTC as an experimental fertility preservation option to young females with TS, medical and ethical concerns need to be addressed. STUDY DESIGN, SIZE, DURATION: A three-round ethical Delphi study was conducted to systematically discuss whether the expected benefits exceed the expected negative consequences of OTC in young females with TS. The aim was to reach group consensus and form an international standpoint based on selected key statements. The study took place between February and December 2018. PARTICIPANTS/MATERIALS, SETTING, METHODS: Anonymous panel selection was based on expertise in TS, fertility preservation or medical ethics. A mixed panel of 12 gynaecologists, 13 (paediatric) endocrinologists, 10 medical ethicists and 20 patient representatives from 16 different countries gave consent to participate in this international Delphi study. In the first two rounds, experts were asked to rate and rank 38 statements regarding OTC in females with TS. Participants were offered the possibility to adjust their opinions after repetitive feedback. The selection of key statements was based on strict inclusion criteria. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 46 participants completed the first Delphi round (response rate 84%). Based on strict selection criteria, six key statements were selected, and 13 statements were discarded. The remaining 19 statements and two additional statements submitted by the expert panel were re-evaluated in the second round by 41 participants (response rate 75%). The analysis of the second survey resulted in the inclusion of two additional key statements. After the approval of these eight key statements, the majority of the expert panel (96%) believed that OTC should be offered to young females with TS, but in a safe and controlled research setting first, with proper counselling and informed consent procedures, before offering this procedure in routine care. The remaining participants (4%) did not object but did not respond despite several reminders. LIMITATIONS, REASONS FOR CAUTION: The anonymous nature of this study may have led to lack of accountability. The selection of experts was based on their willingness to participate. The fact that not all panellists took part in all rounds may have resulted in selection bias. WIDER IMPLICATIONS OF THE FINDINGS: This international standpoint is the first step in the global acceptance of OTC in females with TS. Future collaborative research with a focus on efficacy and safety and long-term follow-up is urgently needed. Furthermore, we recommend an international register for fertility preservation procedures in females with TS. STUDY FUNDING/COMPETING INTEREST(S): Unconditional funding (A16-1395) was received from Merck B.V., The Netherlands. The authors declare that they have no conflict of interest.

To Freeze or Not to Freeze? An Update on Fertility Preservation In Females with Turner Syndrome.

Introduction Infertility is a major concern for females with Turner syndrome (TS), regardless of their age. While fertility preservation is now routinely offered to girls and young women with cancer, there are currently no recommendations on fertility preservation in girls and young women with TS who generally face an even higher risk for infertility. Despite the lack of international guidelines, preservation procedures have been performed experimentally in females with TS. Methods A systematic literature search based on the PRISMA-P methodology for systematic reviews was performed in order to collect all published data on fertility preservation options in females with TS between January 1980 and April 2018. A total number of 67 records were included in this review. The records were screened for information regarding cryopreservation of mature oocytes and ovarian tissue in females with TS. Two ongoing trials on fertility preservation in young females with TS were also included. Results Cryopreservation of oocytes or ovarian tissue has been performed experimentally in >150 girls and adolescents with TS over the last 16 years. The efficacy of fertility preservation options in females with TS is still unknown due to the lack of follow-up data. Conclusion The efficacy of fertility preservation procedures in females with TS is still unknown. Future studies with focus on efficacy, safety and long-term follow-up are desperately needed.

An LGG-derived protein promotes IgA production through upregulation of APRIL expression in intestinal epithelial cells.

p40, a Lactobacillus rhamnosus GG (LGG)-derived protein, transactivates epidermal growth factor receptor (EGFR) in intestinal epithelial cells, leading to amelioration of intestinal injury and inflammation. To elucidate mechanisms by which p40 regulates mucosal immunity to prevent inflammation, this study aimed to determine the effects and mechanisms of p40 on regulation of a proliferation-inducing ligand (APRIL) expression in intestinal epithelial cells for promoting immunoglobulin A (IgA) production. p40 upregulated April gene expression and protein production in mouse small intestine epithelial (MSIE) cells, which were inhibited by blocking EGFR expression and kinase activity. Enteroids from Egfrfl/fl, but not Egfrfl/fl-Vil-Cre mice with EGFR specifically deleted in intestinal epithelial cells, exhibited increased April gene expression by p40 treatment. p40-conditioned media from MSIE cells increased B-cell class switching to IgA+ cells and IgA production, which was suppressed by APRIL receptor-neutralizing antibodies. Treatment of B cells with p40 did not show any effects on IgA production. p40 treatment increased April gene expression and protein production in small intestinal epithelial cells, fecal IgA levels, IgA+B220+, IgA+CD19+, and IgA+ plasma cells in lamina propria of Egfrfl/fl, but not of Egfrfl/fl-Vil-Cre, mice. Thus p40 upregulates EGFR-dependent APRIL production in intestinal epithelial cells, which may contribute to promoting IgA production.

Neonatal colonization of mice with LGG promotes intestinal development and decreases susceptibility to colitis in adulthood.

Development of the intestinal microbiota during early life serves as a key regulatory stage in establishing the host-microbial relationship. This symbiotic relationship contributes to developing host immunity and maintaining health throughout the life span. This study was to develop an approach to colonize conventionally raised mice with a model probiotic bacterium, Lactobacillus rhamnosus GG (LGG), and to determine the effects of LGG colonization on intestinal development and prevention of colitis in adulthood. LGG colonization in conventionally raised was established by administering LGG to pregnant mice starting at gestational day 18 and pups at postnatal days 1- 5. LGG colonization promoted bodyweight gain and increased diversity and richness of the colonic mucosa-associated microbiota before weaning. Intestinal epithelial cell proliferation, differentiation, tight junction formation, and mucosal IgA production were all significantly enhanced in LGG-colonized mice. Adult mice colonized with LGG showed increased IgA production and decreased susceptibility to intestinal injury and inflammation induced in the dextran sodium sulfate model of colitis. Thus, neonatal colonization of mice with LGG enhances intestinal functional maturation and IgA production and confers lifelong health consequences on protection from intestinal injury and inflammation. This strategy might be applied for benefiting health in the host.

Pathogenic Helicobacter pylori strains translocate DNA and activate TLR9 via the cancer-associated cag type IV secretion system.

Helicobacter pylori (H. pylori) is the strongest identified risk factor for gastric cancer, the third most common cause of cancer-related death worldwide. An H. pylori constituent that augments cancer risk is the strain-specific cag pathogenicity island, which encodes a type IV secretion system (T4SS) that translocates a pro-inflammatory and oncogenic protein, CagA, into epithelial cells. However, the majority of persons colonized with CagA+ H. pylori strains do not develop cancer, suggesting that other microbial effectors also have a role in carcinogenesis. Toll-like receptor 9 (TLR9) is an endosome bound, innate immune receptor that detects and responds to hypo-methylated CpG DNA motifs that are most commonly found in microbial genomes. High-expression tlr9 polymorphisms have been linked to the development of premalignant lesions in the stomach. We now demonstrate that levels of H. pylori-mediated TLR9 activation and expression are directly related to gastric cancer risk in human populations. Mechanistically, we show for the first time that the H. pylori cancer-associated cag T4SS is required for TLR9 activation and that H. pylori DNA is actively translocated by the cag T4SS to engage this host receptor. Activation of TLR9 occurs through a contact-dependent mechanism between pathogen and host, and involves transfer of microbial DNA that is both protected as well as exposed during transport. These results indicate that TLR9 activation via the cag island may modify the risk for malignancy within the context of H. pylori infection and provide an important framework for future studies investigating the microbial-epithelial interface in gastric carcinogenesis.

A preliminary study on a new model system to evaluate tumour-detection and tumour-purging protocols in ovarian cortex tissue intended for fertility preservation.

STUDY QUESTION: Is it possible to create a model system that mimics ovarian metastatic disease in order to devise new strategies to detect cancer cells and prevent cancer cell transmission via ovarian tissue autotransplantation in cancer survivors? SUMMARY ANSWER: Injection of bovine or human ovarian cortex fragments with cells from different cancer types led to the formation of proliferating tumour masses and newly formed small metastatic lesions. WHAT IS KNOWN ALREADY: Autotransplantation of ovarian tissue comes with the major concern of cancer cells possibly being present in the tissue. A model system to develop strategies aimed at enhancing the safety of ovarian tissue autotransplantation is currently lacking. STUDY DESIGN, SIZE, DURATION: The ability of injected human leukaemia, lymphoma, Ewing's sarcoma or breast cancer cells to proliferate and form tumour-like structures in bovine and human ovarian cortex tissue in vitro was assessed. The injected cells were from human cancer cell lines. After 4 days of culture, some tissue fragments were harvested for standard histological staining and immunohistochemical staining of tumour cell specific antigens and the Ki67 proliferation marker, while the remaining fragments were incubated for an additional 6 days (bovine tissue) or 3 days (human tissue) before analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Experiments were performed with ovarian tissue from women after prophylactic salpingo-oophorectomy. Bovine ovarian tissue was obtained at an abattoir. Glucose uptake during in vitro culture was monitored to quantify the viability of tissue. Tumour formation was assessed at Day 4 and Day 10 in bovine ovarian tissue and at Day 4 and Day 7 in human ovarian tissue, using histology and immunohistochemistry. MAIN RESULTS AND THE ROLE OF CHANCE: We found that bovine and human ovarian cortex tissue could be cultured for up to 10 and 7 days, respectively, without any loss of viability. Our preliminary results show that all cell lines tested were capable of forming proliferating tumours in ovarian cortex tissue in vitro. Lymphoma and breast cancer cells produced small metastases near the original lesions. LIMITATIONS, REASONS FOR CAUTION: The tumour model presented was based on the growth of human cancer cell lines in ovarian cortex tissue. It is unknown whether these cells behave differently from malignant cells derived from primary tumours. In addition, the human ovarian tissue was derived from women over 39 years of age, which is obviously considerably older than patients opting for ovarian tissue cryopreservation. WIDER IMPLICATIONS OF THE FINDINGS: Our model system will facilitate the development of procedures to detect cancer cells in, or purge cancer cells from, human ovarian tissue. STUDY FUNDING/COMPETING INTERESTS: Unconditional funding was received from the Radboud Institute for Health Sciences, KiKa Foundation and Merck Serono. There are no conflicts of interest to declare.

Matrix metalloproteinase 7 restrains Helicobacter pylori-induced gastric inflammation and premalignant lesions in the stomach by altering macrophage polarization.

Helicobacter pylori is the strongest risk factor for the development of gastric cancer. Although the specific mechanisms by which this pathogen induces carcinogenesis have not been fully elucidated, high-expression interleukin (IL)-1ß alleles are associated with increased gastric cancer risk among H. pylori-infected persons. In addition, loss of matrix metalloproteinase 7 (MMP7) increases mucosal inflammation in mouse models of epithelial injury, and we have shown that gastric inflammation is increased in H. pylori-infected MMP7(-/-) C57BL/6 mice. In this report, we define mechanisms that underpin such responses and extend these results into a genetic model of MMP7 deficiency and gastric cancer. Wild-type (WT) or MMP7(-/-) C57BL/6 mice were challenged with broth alone as an uninfected control or the H. pylori strain PMSS1. All H. pylori-challenged mice were successfully colonized. As expected, H. pylori-infected MMP7(-/-) C57BL/6 mice exhibited a significant increase in gastric inflammation compared with uninfected or infected WT C57BL/6 animals. Loss of MMP7 resulted in M1 macrophage polarization within H. pylori-infected stomachs, as assessed by Luminex technology and immunohistochemistry, and macrophages isolated from infected MMP7-deficient mice expressed significantly higher levels of the M1 macrophage marker IL-1ß compared with macrophages isolated from WT mice. To extend these findings into a model of gastric cancer, hypergastrinemic WT INS-GAS or MMP7(-/-) INS-GAS mice were challenged with H. pylori strain PMSS1. Consistent with findings in the C57BL/6 model, H. pylori-infected MMP7-deficient INS-GAS mice exhibited a significant increase in gastric inflammation compared with either uninfected or infected WT INS-GAS mice. In addition, the incidence of gastric hyperplasia and dysplasia was significantly increased in H. pylori-infected MMP7(-/-) INS-GAS mice compared with infected WT INS-GAS mice, and loss of MMP7 promoted M1 macrophage polarization. These results suggest that MMP7 exerts a restrictive role on H. pylori-induced gastric injury and the development of premalignant lesions by suppressing M1 macrophage polarization.

Increased Helicobacter pylori-associated gastric cancer risk in the Andean region of Colombia is mediated by spermine oxidase.

Helicobacter pylori infection causes gastric cancer, the third leading cause of cancer death worldwide. More than half of the world's population is infected, making universal eradication impractical. Clinical trials suggest that antibiotic treatment only reduces gastric cancer risk in patients with non-atrophic gastritis (NAG), and is ineffective once preneoplastic lesions of multifocal atrophic gastritis (MAG) and intestinal metaplasia (IM) have occurred. Therefore, additional strategies for risk stratification and chemoprevention of gastric cancer are needed. We have implicated polyamines, generated by the rate-limiting enzyme ornithine decarboxylase (ODC), in gastric carcinogenesis. During H. pylori infection, the enzyme spermine oxidase (SMOX) is induced, which generates hydrogen peroxide from the catabolism of the polyamine spermine. Herein, we assessed the role of SMOX in the increased gastric cancer risk in Colombia associated with the Andean mountain region when compared with the low-risk region on the Pacific coast. When cocultured with gastric epithelial cells, clinical strains of H. pylori from the high-risk region induced more SMOX expression and oxidative DNA damage, and less apoptosis than low-risk strains. These findings were not attributable to differences in the cytotoxin-associated gene A oncoprotein. Gastric tissues from subjects from the high-risk region exhibited greater levels of SMOX and oxidative DNA damage by immunohistochemistry and flow cytometry, and this occurred in NAG, MAG and IM. In Mongolian gerbils, a prototype colonizing strain from the high-risk region induced more SMOX, DNA damage, dysplasia and adenocarcinoma than a colonizing strain from the low-risk region. Treatment of gerbils with either α-difluoromethylornithine, an inhibitor of ODC, or MDL 72527 (N(1),N(4)-Di(buta-2,3-dien-1-yl)butane-1,4-diamine dihydrochloride), an inhibitor of SMOX, reduced gastric dysplasia and carcinoma, as well as apoptosis-resistant cells with DNA damage. These data indicate that aberrant activation of polyamine-driven oxidative stress is a marker of gastric cancer risk and a target for chemoprevention.

Efficacy of ovarian tissue cryopreservation in a major European center.

PURPOSE: To evaluate the effect of cryopreservation and thawing of ovarian tissue from oncological patients opting for fertility preservation on ovarian tissue viability. METHODS: In this prospective cohort study, the ovarian tissue viability before and after cryopreservation and thawing was measured for 25 newly diagnosed oncological patients who had their ovarian tissue cryopreserved. Outcome measures were follicle integrity (histology), follicle viability (Calcein viability assay), steroid hormone production (estradiol and progesterone production in vitro) and overall tissue viability (glucose uptake in vitro). This study was conducted at a Cryobank for storage of ovarian tissue in a university hospital. RESULTS: Cryopreserved/thawed ovarian tissue showed a decreased glucose uptake when compared to tissue that had not been cryopreserved. In addition, a diminished E2 and P4 production was observed after cryopreservation and thawing, despite the fact that numbers of viable follicles as determined by the Calcein viability assay were comparable. Histological examination revealed a higher percentage of degenerated follicles after cryopreservation and thawing. CONCLUSIONS: Ovarian tissue cryopreservation and thawing impairs the viability of ovarian tissue in oncological patients opting for fertility preservation.

Autotransplantation of cryopreserved ovarian tissue in cancer survivors and the risk of reintroducing malignancy: a systematic review.

BACKGROUND The risk of recurrent oncological disease due to the reintroduction of cancer cells via autotransplantation of cryopreserved ovarian tissue is unknown. METHODS A systematic review of literature derived from MEDLINE, EMBASE and the Cochrane Library was conducted. Studies on follow-up after autotransplantation; detection of cancer cells in ovarian tissue from oncological patients by histology, polymerase chain reaction or xenotransplantation; and epidemiological data on ovarian metastases were included. RESULTS A total of 289 studies were included. Metastases were repeatedly detected in ovarian tissue obtained for cryopreservation purposes from patients with leukaemia, as well as in one patient with Ewing sarcoma. No metastases were detected in ovarian tissue from lymphoma and breast cancer patients who had their ovarian tissue cryopreserved. Clinical studies indicated that one should be concerned about autotransplantation safety in patients with colorectal, gastric and endometrial cancer. For patients with low-stage cervical carcinoma, clinical data were relatively reassuring, but studies focused on the detection of metastases were scarce. Oncological recurrence has been described in one survivor of cervical cancer and one survivor of breast cancer who had their ovarian tissue autotransplanted, although these recurrences may not be related to the transplantation. CONCLUSIONS It is advisable to refrain from ovarian tissue autotransplantation in survivors of leukaemia. With survivors of all other malignancies, current knowledge regarding the safety of autotransplantation should be discussed. The most reassuring data regarding autotransplantation safety were found for lymphoma patients.

Scalp metastases--an unusual presentation of non-small cell lung cancer prognosis of cutaneous metastases in the current era.

We report a case of metastatic lung cancer presenting as scalp metastases. Immunohistochemistry and radiological investigations helped in making the diagnosis. We also report better survival as seen in our present case using newer chemotherapeutic agents. The report emphasizes the need to look carefully for skin lesions as they provide easily accessible tissue for histopathology and also aid in proper staging as they can be missed out on routine radiological investigations. The case also reflects improvement in cancer care and outcomes in recent times.

Management of precancerous conditions and lesions in the stomach (MAPS): guideline from the European Society of Gastrointestinal Endoscopy (ESGE), European Helicobacter Study Group (EHSG), European Society of Pathology (ESP), and the Sociedade Portuguesa de Endoscopia Digestiva (SPED).

Atrophic gastritis, intestinal metaplasia, and epithelial dysplasia of the stomach are common and are associated with an increased risk for gastric cancer. In the absence of guidelines, there is wide disparity in the management of patients with these premalignant conditions. The European Society of Gastrointestinal Endoscopy, the European Helicobacter Study Group, the European Society of Pathology, and the Sociedade Portuguesa de Endoscopia Digestiva have therefore combined efforts to develop evidence-based guidelines on the management of patients with precancerous conditions and lesions of the stomach. A multidisciplinary group of 63 experts from 24 countries developed these recommendations by means of repeat online voting and a meeting in June 2011 in Porto, Portugal. The recommendations emphasize the increased cancer risk in patients with gastric atrophy and metaplasia and the need for adequate staging in the case of high-grade dysplasia, and they focus on treatment and surveillance indications and methods.

Management of precancerous conditions and lesions in the stomach (MAPS): guideline from the European Society of Gastrointestinal Endoscopy (ESGE), European Helicobacter Study Group (EHSG), European Society of Pathology (ESP), and the Sociedade Portuguesa de Endoscopia Digestiva (SPED).

Atrophic gastritis, intestinal metaplasia, and epithelial dysplasia of the stomach are common and are associated with an increased risk for gastric cancer. In the absence of guidelines, there is wide disparity in the management of patients with these premalignant conditions. The European Society of Gastrointestinal Endoscopy (ESGE), the European Helicobacter Study Group (EHSG), the European Society of Pathology (ESP) and the Sociedade Portuguesa de Endoscopia Digestiva (SPED) have therefore combined efforts to develop evidence-based guidelines on the management of patients with precancerous conditions and lesions of the stomach (termed MAPS). A multidisciplinary group of 63 experts from 24 countries developed these recommendations by means of repeat online voting and a meeting in June 2011 in Porto, Portugal. The recommendations emphasize the increased cancer risk in patients with gastric atrophy and metaplasia, and the need for adequate staging in the case of high grade dysplasia, and they focus on treatment and surveillance indications and methods.

Glucose/lactate metabolism of cryopreserved intact bovine ovaries as a novel quantitative marker to assess tissue cryodamage.

For some patients, the autotransplantation of a cryopreserved-thawed intact ovary might be the best option to preserve their reproductive potential after fertility-threatening treatment. The best procedure to successfully cryopreserve a human ovary without inflicting a devastating level of cryodamage is to date unknown. To optimize this procedure, this study developed an assay to monitor the extent of cryodamage inflicted on bovine ovarian tissue by different cryopreservation protocols. The assay measures glucose and lactate metabolism of ovarian tissue fragments in vitro and determines the extent of cryodamage in cryopreserved ovaries. This study tested the cryoprotective effect of two different routes of administration of the cryoprotectant dimethylsulphoxide (DMSO). The cryoprotective effect was assessed in different tissue layers of the ovary, namely the cortex, the subcortex and the medulla. Submersion of intact ovaries in DMSO prior to freezing-thawing resulted in the complete protection of the glucose/lactate metabolism of the cortex, but not of the inner ovarian mass. Perfusion without simultaneous submersion, resulted in partial protection of cortex, subcortex and medulla, while the combination of submersion and perfusion conveyed the highest level of protection for all three ovarian tissue layers.

In vitro 17ß-oestradiol release as a marker for follicular survival in cryopreserved intact bovine ovaries.

Transplantation of cryopreserved intact ovaries from cancer patients is a technically challenging option for restoring fertility after sterilizing cancer therapy. In this paper we describe an assay based on 17ß-oestradiol (oestradiol) production, to monitor the functional damage sustained by the ovarian tissue during the freeze/thawing procedure. To this end, fresh bovine ovarian cortical biopsies were cultured in vitro for 7 days. As a control, the oestradiol release of biopsies that had sustained maximal cryodamage was analyzed. In addition the oestradiol release by cortical biopsies from two ME2SO perfused and cryopreserved intact ovaries was analyzed. Oestradiol production could be measured in culture supernatants, while oestradiol release of maximal cryo-damaged biopsies was at background levels. In vitro oestradiol release by cortical biopsies can be used as a functional marker for cryo-damage and indicates that our assay is suitable to optimize the cryopreservation procedure of intact ovaries.

Helicobacter pylori CagA targets gastric tumor suppressor RUNX3 for proteasome-mediated degradation.

Chronic infection with cagA-positive Helicobacter pylori is the strongest risk factor for the development of gastric adenocarcinoma. The cagA gene product CagA is injected into gastric epithelial cells and disturbs cellular functions by physically interacting with and deregulating a variety of cellular signaling molecules. RUNX3 is a tumor suppressor in many tissues, and it is frequently inactivated in gastric cancer. In this study, we show that H. pylori infection inactivates the gastric tumor suppressor RUNX3 in a CagA-dependent manner. CagA directly associates with RUNX3 through a specific recognition of the PY motif of RUNX3 by a WW domain of CagA. Deletion of the WW domains of CagA or mutation of the PY motif in RUNX3 abolishes the ability of CagA to induce the ubiquitination and degradation of RUNX3, thereby extinguishing its ability to inhibit the transcriptional activation of RUNX3. Our studies identify RUNX3 as a novel cellular target of H. pylori CagA and also reveal a mechanism by which CagA functions as an oncoprotein by blocking the activity of gastric tumor suppressor RUNX3.

CagA C-terminal variations in Helicobacter pylori strains from Colombian patients with gastric precancerous lesions.

The C-terminus of the Helicobacter pylori CagA protein is polymorphic, bearing different EPIYA sequences (EPIYA-A, B, C or D), and one or more CagA multimerization (CM) motifs. The number of EPIYA-C motifs is associated with precancerous lesions and gastric cancer (GC). The relationship between EPIYA, CM motifs and gastric lesions was examined in H. pylori-infected Colombian patients from areas of high and low risk for GC. Genomic DNA was extracted from H. pylori strains cultured from gastric biopsies from 80 adults with dyspeptic symptoms. Sixty-seven (83.8%) of 80 strains were cagA positive. The 3' region of cagA was sequenced, and EPIYA and CM motifs were identified. CagA proteins contained one (64.2%), two (34.3%) or three EPIYA-C motifs (1.5%), all with Western type CagA-specific sequences. Strains with one EPIYA-C motif were associated with less severe gastric lesions (non-atrophic and multifocal atrophic gastritis), whereas strains with multiple EPIYA-C motifs were associated with more severe lesions (intestinal metaplasia and dysplasia) (p <0.001). In 54 strains, the CM motifs were identical to those common in Western strains. Thirteen strains from the low-risk area contained two different CM motifs: one of Western type located within the EPIYA-C segment and another following the EPIYA-C segment and resembling the CM motif found in East Asian strains. These strains induced significantly shorter projections in AGS cells and an attenuated reduction in levels of CagA upon immunodepletion of SHP-2 than strains possessing Western/Western motifs. This novel finding may partially explain the difference in GC incidence in these populations.