80 research outputs found
The parafibromin tumor suppressor protein interacts with actin-binding proteins actinin-2 and actinin-3
<p>Abstract</p> <p>Background</p> <p>Germline and somatic inactivating mutations in the <it>HRPT2 </it>gene occur in the inherited hyperparathyroidism-jaw tumor syndrome, in some cases of parathyroid cancer and in some cases of familial hyperparathyroidism. <it>HRPT2 </it>encodes parafibromin. To identify parafibromin interacting proteins we used the yeast two-hybrid system for screening a heart cDNA library with parafibromin as the bait.</p> <p>Results</p> <p>Fourteen parafibromin interaction positive preys representing 10 independent clones encoding actinin-2 were isolated. Parafibromin interacted with muscle alpha-actinins (actinin-2 and actinin-3), but not with non-muscle alpha-actinins (actinin-1 and actinin-4). The parafibromin-actinin interaction was verified by yeast two-hybrid, GST pull-down, and co-immunoprecipitation. Yeast two-hybrid analysis revealed that the N-terminal region of parafibromin interacted with actinins. In actin sedimentation assays parafibromin did not dissociate skeletal muscle actinins from actin filaments, but interestingly, parafibromin could also bundle/cross-link actin filaments. Parafibromin was predominantly nuclear in undifferentiated proliferating myoblasts (C2C12 cells), but in differentiated C2C12 myotubes parafibromin co-localized with actinins in the cytoplasmic compartment.</p> <p>Conclusion</p> <p>These data support a possible contribution of parafibromin outside the nucleus through its interaction with actinins and actin bundling/cross-linking. These data also suggest that actinins (and actin) participate in sequestering parafibromin in the cytoplasmic compartment.</p
Complementary feeding at 4 versus 6 months of age for preterm infants born at less than 34 weeks of gestation: a randomised, open-label, multicentre trial
Background Evidence on the optimal time to initiation of complementary feeding in preterm infants is scarce.
We examined the effect of initiation of complementary feeding at 4 months versus 6 months of corrected age on
weight for age at 12 months corrected age in preterm infants less than 34 weeks of gestation.
Methods In this open-label, randomised trial, we enrolled infants born at less than 34 weeks of gestation with no major
malformation from three public health facilities in India. Eligible infants were tracked from birth and randomly
assigned (1:1) at 4 months corrected age to receive complementary feeding at 4 months corrected age (4 month group), or
continuation of milk feeding and initiation of complementary feeding at 6 months corrected age (6 month group), using
computer generated randomisation schedule of variable block size, stratified by gestation (30 weeks or less, and
31β33 weeks). Iron supplementation was provided as standard. Participants and the implementation team could not be
masked to group assignment, but outcome assessors were masked. Primary outcome was weight for age Z-score at
12 months corrected age (WAZ12) based on WHO Multicentre Growth Reference Study growth standards. Analyses were
by intention to treat. The trial is registered with Clinical Trials Registry of India, number CTRI/2012/11/003149.
Findings Between March 20, 2013, and April 24, 2015, 403 infants were randomly assigned: 206 to receive
complementary feeding from 4 months and 197 to receive complementary feeding from 6 months. 22 infants in the
4 month group (four deaths, two withdrawals, 16 lost to follow-up) and eight infants in the 6 month group (two deaths,
six lost to follow-up) were excluded from analysis of primary outcome. There was no difference in WAZ12 between
two groups: β1Β·6 (SD 1Β·2) in the 4 month group versus β1Β·6 (SD 1Β·3) in the 6 month group (mean difference 0Β·005,
95% CI β0Β·24 to 0Β·25; p=0Β·965). There were more hospital admissions in the 4 month group compared with the
6 month group: 2Β·5 episodes per 100 infant-months in the 4 month group versus 1Β·4 episodes per 100 infant-months
in the 6 month group (incidence rate ratio 1Β·8, 95% CI 1Β·0β3Β·1, p=0Β·03). 34 (18%) of 188 infants in the 4 month
group required hospital admission, compared with 18 (9%) of 192 infants in the 6 month group.
Interpretation Although there was no evidence of effect for the primary endpoint of WAZ12, the higher rate of hospital
admission in the 4 month group suggests a recommendation to initiate complementary feeding at 6 months over
4 months of corrected age in infants less than 34 weeks of gestation
Patients with MEN1 are at an increased risk for venous thromboembolism VTE risk in MEN1
Background: Multiple endocrine neoplasia type 1 (MEN1) is a rare inherited disorder predisposing to the development of multiple functional and non-functional neuroendocrine tumors (NETs). Only uncommon MEN1-associated functional NETs such as glucagonomas (<1%) and ACTH-producing tumors (<5%) are known to be associated with hypercoagulability. It is unknown if patients with MEN1 generally have increased risk of VTE.
Methods: We queried a prospective natural history study of germline mutation positive MEN1 patients (n=286) between 1991-2019 for all lifetime events of VTE. Search terms were: DVT, thromb, embol, PE, pulmonary embolism, clot, hematology consult, anticoagulant, coumadin, lovenox, xarelto, warfarin, aspirin, rivaroxaban and apixaban. Incidence rates were calculated accounting for age and sex. Comparison was made to published incidence rates in healthy populations, different types of cancer, and Cushing's syndrome.
Results: Thirty-six subjects (median age 45 years, range 16-75) experienced a VTE event, yielding a prevalence rate of 12.9%. The age-sex adjusted incidence rate of VTE is 9.11 per 1,000 patient-years, with a sex-adjusted lifetime incidence rate of 2.81 per 1,000 patient-years. MEN1-associated lifetime incidence rates are ~two-fold higher than the estimated annual incidence rate in the general population and are comparable to known risk in the setting of various types of cancer. Approximately 80% were diagnosed with pancreatic NETs, of which 24% were insulinomas. Fourteen patients (42%) experienced peri-operative VTE events.
Conclusions: MEN1 patients have an increased risk of VTE. Further mechanistic investigation and validation from other MEN1 cohorts are needed to confirm the increased prevalence of VTE in MEN1
Genome-Wide Analysis of Menin Binding Provides Insights into MEN1 Tumorigenesis
Multiple endocrine neoplasia type I (MEN1) is a familial cancer syndrome characterized primarily by tumors of multiple endocrine glands. The gene for MEN1 encodes a ubiquitously expressed tumor suppressor protein called menin. Menin was recently shown to interact with several components of a trithorax family histone methyltransferase complex including ASH2, Rbbp5, WDR5, and the leukemia proto-oncoprotein MLL. To elucidate menin's role as a tumor suppressor and gain insights into the endocrine-specific tumor phenotype in MEN1, we mapped the genomic binding sites of menin, MLL1, and Rbbp5, to approximately 20,000 promoters in HeLa S3, HepG2, and pancreatic islet cells using the strategy of chromatin-immunoprecipitation coupled with microarray analysis. We found that menin, MLL1, and Rbbp5 localize to the promoters of thousands of human genes but do not always bind together. These data suggest that menin functions as a general regulator of transcription. We also found that factor occupancy generally correlates with high gene expression but that the loss of menin does not result in significant changes in most transcript levels. One exception is the developmentally programmed transcription factor, HLXB9, which is overexpressed in islets in the absence of menin. Our findings expand the realm of menin-targeted genes several hundred-fold beyond that previously described and provide potential insights to the endocrine tumor bias observed in MEN1 patients
Genome-Wide Characterization of Menin-Dependent H3K4me3 Reveals a Specific Role for Menin in the Regulation of Genes Implicated in MEN1-Like Tumors
Inactivating mutations in the MEN1 gene predisposing to the multiple endocrine neoplasia type 1 (MEN1) syndrome can also cause sporadic pancreatic endocrine tumors. MEN1 encodes menin, a subunit of MLL1/MLL2-containing histone methyltransferase complexes that trimethylate histone H3 at lysine 4 (H3K4me3). The importance of menin-dependent H3K4me3 in normal and transformed pancreatic endocrine cells is unclear. To study the role of menin-dependent H3K4me3, we performed in vitro differentiation of wild-type as well as menin-null mouse embryonic stem cells (mESCs) into pancreatic islet-like endocrine cells (PILECs). Gene expression analysis and genome-wide H3K4me3 ChIP-Seq profiling in wild-type and menin-null mESCs and PILECs revealed menin-dependent H3K4me3 at the imprinted Dlk1-Meg3 locus in mESCs, and all four Hox loci in differentiated PILECs. Specific and significant loss of H3K4me3 and gene expression was observed for genes within the imprinted Dlk1-Meg3 locus in menin-null mESCs and the Hox loci in menin-null PILECs. Given that the reduced expression of genes within the DLK1-MEG3 locus and the HOX loci is associated with MEN1-like sporadic tumors, our data suggests a possible role for menin-dependent H3K4me3 at these genes in the initiation and progression of sporadic pancreatic endocrine tumors. Furthermore, our investigation also demonstrates that menin-null mESCs can be differentiated in vitro into islet-like endocrine cells, underscoring the utility of menin-null mESC-derived specialized cell types for genome-wide high-throughput studies
Blood-based Proteomic Signatures Associated With MEN1-related Duodenopancreatic Neuroendocrine Tumor Progression
PURPOSE: Patients with multiple endocrine neoplasia type 1 (MEN1) are predisposed to develop duodenopancreatic neuroendocrine tumors (dpNETs), and metastatic dpNET is the primary cause of disease-related mortality. Presently, there is a paucity of prognostic factors that can reliably identify patients with MEN1-related dpNETS who are at high risk of distant metastasis. In the current study, we aimed to establish novel circulating molecular protein signatures associated with disease progression.
EXPERIMENTAL DESIGN: Mass spectrometry-based proteomic profiling was conducted on plasmas procured through an international collaboration between MD Anderson Cancer Center, the National Institutes of Health, and the University Medical Center Utrecht from a cohort of 56 patients with MEN1 [14 with distant metastasis dpNETs (cases) and 42 with either indolent dpNETs or no dpNETs (controls)]. Findings were compared to proteomic profiles generated from serially collected plasmas from a mouse model of Men1-pancreatic neuroendocrine tumors (Men1fl/flPdx1-CreTg) and control mice (Men1fl/fl).
RESULTS: A total of 187 proteins were found to be elevated in MEN1 patients with distant metastasis compared to controls, including 9 proteins previously associated with pancreatic cancer and other neuronal proteins. Analyses of mouse plasmas revealed 196 proteins enriched for transcriptional targets of oncogenic MYCN, YAP1, POU5F1, and SMAD that were associated with disease progression in Men1fl/flPdx1-CreTg mice. Cross-species intersection revealed 19 proteins positively associated with disease progression in both human patients and in Men1fl/flPdx1-CreTg mice.
CONCLUSIONS: Our integrated analyses identified novel circulating protein markers associated with disease progression in MEN1-related dpNET
In vitro PHYTOTHERAPY OF VECTOR SNAILS BY BINARY COMBINATIONS OF LARVICIDAL ACTIVE COMPONENTS IN EFFECTIVE CONTROL OF FASCIOLIASIS
SUMMARY A food-borne trematode infection fascioliasis is one among common public health problems worldwide. It caused a great economic loss for the human race. Control of snail population below a certain threshold level is one of the important methods in the campaign to reduce the incidence of fascioliasis. The life cycle of the parasite can be interrupted by killing the snail or Fasciola larva redia and cercaria inside of the snail Lymnaea acuminata. In vitro toxicity of different binary combinations (1:1 ratio) of plant-derived larvicidal active components such as citral, ferulic acid, umbelliferone, azadirachtin and allicin against Fasciola redia and cercaria were tested. The mortality of larvae was observed at 2h, 4h, 6h and 8h of treatment. In in vitro condition azadirachtin + allicin (1:1 ratio) was highly toxic against redia and cercaria (8h LC50 0.006 and 0.005 mg/L). Toxicity of citral + ferulic acid was lowest against redia and cercaria larvae
Characterization of miRNAs in Response to Short-Term Waterlogging in Three Inbred Lines of Zea mays
Waterlogging of plants leads to low oxygen levels (hypoxia) in the roots and causes a metabolic switch from aerobic respiration to anaerobic fermentation that results in rapid changes in gene transcription and protein synthesis. Our research seeks to characterize the microRNA-mediated gene regulatory networks associated with short-term waterlogging. MicroRNAs (miRNAs) are small non-coding RNAs that regulate many genes involved in growth, development and various biotic and abiotic stress responses. To characterize the involvement of miRNAs and their targets in response to short-term hypoxia conditions, a quantitative real time PCR (qRT-PCR) assay was used to quantify the expression of the 24 candidate mature miRNA signatures (22 known and 2 novel mature miRNAs, representing 66 miRNA loci) and their 92 predicted targets in three inbred Zea mays lines (waterlogging tolerant Hz32, mid-tolerant B73, and sensitive Mo17). Based on our studies, miR159, miR164, miR167, miR393, miR408 and miR528, which are mainly involved in root development and stress responses, were found to be key regulators in the post-transcriptional regulatory mechanisms under short-term waterlogging conditions in three inbred lines. Further, computational approaches were used to predict the stress and development related cis-regulatory elements on the promoters of these miRNAs; and a probable miRNA-mediated gene regulatory network in response to short-term waterlogging stress was constructed. The differential expression patterns of miRNAs and their targets in these three inbred lines suggest that the miRNAs are active participants in the signal transduction at the early stage of hypoxia conditions via a gene regulatory network; and crosstalk occurs between different biochemical pathways
Menin-dependent regulation of <i>Hox</i> genes in PILECs.
<p>(A) Expression fold changes of genes that showed at least 4-fold change (p-value <0.005) in menin-null (KO) PILECs vs wild-type (WT) PILECs in microarray analysis. (B) RT-PCR analysis measuring mRNA levels of 39 <i>Hox</i> genes from the 4 <i>Hox</i> clusters (<i>HoxA</i>, <i>HoxB</i>, <i>HoxC</i> and <i>HoxD</i>) using RNA from wild-type (WT) or menin-null (KO) mESC-derived PILECs. Gapdh served as an internal control for RT-PCR using a 1βΆ10 dilution of the oligo-dT primed first strand cDNA template. Blank boxes represent <i>Hox</i> genes whose expression was undetectable in the WT or KO cells.</p
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