Human chorionic gonadotropin decreases cerebral cystic encephalomalacia and parvalbumin interneuron degeneration in a pro-inflammatory model of mouse neonatal hypoxia-ischemia.

The pregnancy hormone, human chorionic gonadotropin (hCG) is an immunoregulatory and neurotrophic glycoprotein of potential clinical utility in the neonate at risk for cerebral injury. Despite its well-known role in its ability to modulate the innate immune response during pregnancy, hCG has not been demonstrated to affect the pro-degenerative actions of inflammation in neonatal hypoxia-ischemia (HI). Here we utilize a neonatal mouse model of mild HI combined with intraperitoneal administration of lipopolysaccharide (LPS) to evaluate the neuroprotective actions of hCG in the setting of endotoxin-mediated systemic inflammation. Intraperitoneal treatment of hCG shortly prior to LPS injection significantly decreased tissue loss and cystic degeneration in the hippocampal and cerebral cortex in the term-equivalent neonatal mouse exposed to mild HI. Noting that parvalbumin immunoreactive interneurons have been broadly implicated in neurodevelopmental disorders, it is notable that hCG significantly improved the injury-mediated reduction of these neurons in the cerebral cortex, striatum and hippocampus. The above findings were associated with a decrease in the amount of Iba1 immunoreactive microglia in most of these brain regions. These observations implicate hCG as an agent capable of improving the neurological morbidity associated with peripheral inflammation in the neonate affected by HI. Future preclinical studies should aim at demonstrating added neuroprotective benefit by hCG in the context of therapeutic hypothermia and further exploring the mechanisms responsible for this effect. This research is likely to advance the therapeutic role of gonadotropins as a treatment for neonates with neonatal brain injury.

Mycoplasma DnaK expression increases cancer development in vivo upon DNA damage.

Well-controlled repair mechanisms are involved in the maintenance of genomic stability, and their failure can precipitate DNA abnormalities and elevate tumor risk. In addition, the tumor microenvironment, enriched with factors inducing oxidative stress and affecting cell cycle checkpoints, intensifies DNA damage when repair pathways falter. Recent research has unveiled associations between certain bacteria, including Mycoplasmas, and various cancers, and the causative mechanism(s) are under active investigation. We previously showed that Mycoplasma fermentans DnaK, an HSP70 family chaperone protein, hampers the activity of proteins like PARP1 and p53, crucial for genomic integrity. Moreover, our analysis of its interactome in human cancer cell lines revealed DnaK's engagement with several components of DNA-repair machinery. Finally, in vivo experiments performed in our laboratory using a DnaK knock-in mouse model generated by our group demonstrated that DnaK exposure led to increased DNA copy number variants, indicative of genomic instability. We present here evidence that expression of DnaK is linked to increased i) incidence of tumors in vivo upon exposure to urethane, a DNA damaging agent; ii) spontaneous DNA damage ex vivo; and iii) expression of proinflammatory cytokines ex vivo, variations in reactive oxygen species levels, and increased ß-galactosidase activity across tissues. Moreover, DnaK was associated with increased centromeric instability. Overall, these findings highlight the significance of Mycoplasma DnaK in the etiology of cancer and other genetic disorders providing a promising target for prevention, diagnostics, and therapeutics.

Mice born preterm develop gait dystonia and reduced cortical parvalbumin immunoreactivity.

Preterm birth leading to cerebral palsy (CP) is the most common cause of childhood dystonia, a movement disorder that is debilitating and often treatment refractory. Dystonia has been typically associated with dysfunction of striatal cholinergic interneurons, but clinical imaging data suggests that cortical injury may best predict dystonia following preterm birth. Furthermore, abnormal sensorimotor cortex inhibition has been found in many studies of non-CP dystonias. To assess the potential for a cortical etiology of dystonia following preterm birth, we developed a new model of preterm birth in mice. Noting that term delivery in mice on a C57BL/6J background is embryonic day 19.1 (E19.1), we induced preterm birth at the limits of pup viability at embryonic day (E) 18.3, equivalent to human 22 weeks gestation. Mice born preterm demonstrate display clinically validated metrics of dystonia during gait (leg adduction amplitude and variability) and also demonstrate reduced parvalbumin immunoreactivity in the sensorimotor cortex, suggesting dysfunction of cortical parvalbumin-positive inhibitory interneurons. Notably, reduced parvalbumin immunoreactivity or changes in parvalbumin-positive neuronal number were not observed in the striatum. These data support the association between cortical dysfunction and dystonia following preterm birth. We propose that our mouse model of preterm birth can be used to study this association and potentially also study other sequelae of extreme prematurity.

Fyn-mediated phosphorylation of Menin disrupts telomere maintenance in stem cells.

Telomeres protect chromosome ends and determine the replication potential of dividing cells. The canonical telomere sequence TTAGGG is synthesized by telomerase holoenzyme, which maintains telomere length in proliferative stem cells. Although the core components of telomerase are well-defined, mechanisms of telomerase regulation are still under investigation. We report a novel role for the Src family kinase Fyn, which disrupts telomere maintenance in stem cells by phosphorylating the scaffold protein Menin. We found that Fyn knockdown prevented telomere erosion in human and mouse stem cells, validating the results with four telomere measurement techniques. We show that Fyn phosphorylates Menin at tyrosine 603 (Y603), which increases Menin's SUMO1 modification, C-terminal stability, and importantly, its association with the telomerase RNA component (TR). Using mass spectrometry, immunoprecipitation, and immunofluorescence experiments we found that SUMO1-Menin decreases TR's association with telomerase subunit Dyskerin, suggesting that Fyn's phosphorylation of Menin induces telomerase subunit mislocalization and may compromise telomerase function at telomeres. Importantly, we find that Fyn inhibition reduces accelerated telomere shortening in human iPSCs harboring mutations for dyskeratosis congenita.

Resultado de la actualización de la vía clínica de la fractura de cadera del anciano en un hospital universitario de Madrid / Result of the update of the clinical pathway for hip fracture in the older adult at a university hospital in Madrid

Antecedentes y objetivos: El manejo ortogeriátrico con vías clínicas (VC) en la fractura de cadera (FC) se muestra superior a otros modelos. Estudiamos si actualizar la VC, mediante la priorización organizativa del ingreso y la cirugía, mejora en la prevención y tratamiento del delirium, el manejo de anticoagulantes y antiagregantes y el uso del bloqueo periférico nervioso perioperatorio, modifica la demora quirúrgica, estancia, reingresos, mortalidad, delirium y estado funcional al alta. Material y método: Estudio observacional retrospectivo de cohortes unicéntrico de 468 pacientes con FC, 220 del año 2016 (VC antigua) y 248 del año 2019 (VC nueva). Las variables son: intervención en 48h, demora quirúrgica (horas), estancia (días), estancia menor de 15 días, delirium, pérdida funcional al alta (escala Barthel prefractura menos escala Barthel al alta), reingreso al mes, y mortalidad en el ingreso, al mes y al año. Resultados: Mediana de edad de 87,0 [rango intercuartílico 8,0], mujeres 76,7%. Significativamente con la nueva VC se observa un mayor número de pacientes intervenidos en 48h (27,7% vs. 36,8%; p=0,036), menor demora quirúrgica (72,5 [47,5-110,5] vs. 64,0 [42,0-88,0]; p=0,001), menor estancia (10,0 [7,0-13,0] vs. 8,0 [6,0-11,0]; p<0,001), mayor número de altas en 15 días (78,2% vs. 91,5%; p<0,001), menor delirium (54,1% vs. 43,5%; p=0,023). No se detectan cambios significativos en reingresos, pérdida funcional, mortalidad en el ingreso, a los 3 meses o al año. Conclusiones: Actualizar la VC aporta beneficios al paciente (menor demora quirúrgica, igual estado funcional al alta con menos días de ingreso) y beneficios en la gestión (menor ingreso) sin modificar la mortalidad. (AU)

Background and objectives: Orthogeriatric management with clinical pathways (CP) in hip fracture (HF) has been shown to be superior to other models. We studied whether updating the CP, through prioritization of admission and surgery, improvement in the prevention and treatment of delirium, management of anticoagulants and antiplatelet agents and the use of perioperative peripheral nerve block, modifies surgical delay, stay, readmissions, mortality, suffering delirium and functional status at discharge. Material and method: A retrospective observational study of unicenter cohorts of 468 patients with HF, 220 from 2016 (old VC) and 248 from 2019 (new VC). The variables are: intervention in the first 48hours, surgical delay (hours), stay (days), stay less than 15 days, delirium, functional loss at discharge (Barthel prefracture scale less Barthel scale at discharge), readmission at one month, and mortality at admission, month and year. Results: Median age: 87.0 [interquartile range 8.0], mostly women (76.7%). Significantly, with the new VC, there was a greater number of patients operated on in the first 48hours (27,7% vs 36,8% p=0.036), less surgical delay (72.5 [47,5-110,5] vs 64.0 [42,0-88,0] p<0.001), shorter stay (10,0 [7,0-13,0] vs 8,0 [6,0-11,0] p<0.001), greater number of discharges in 15 days (78,2% vs 91,5% p<0.001), lower delirium (54,1% vs 43,5% p=0.023). No significant changes in readmissions, functional loss at discharge, mortality at admission, 3 months or year.Conclusions: Updating the VC brings benefits to the patient (less surgical delay, equal functional status at discharge with fewer days of admission) and benefits in management (lower admission) without modifying mortality. (AU)

[Result of the update of the clinical pathway for hip fracture in the older adult at a university hospital in Madrid]. / Resultado de la actualización de la vía clínica de la fractura de cadera del anciano en un hospital universitario de Madrid.

BACKGROUND AND OBJECTIVES: Orthogeriatric management with clinical pathways (CP) in hip fracture (HF) has been shown to be superior to other models. We studied whether updating the CP, through prioritization of admission and surgery, improvement in the prevention and treatment of delirium, management of anticoagulants and antiplatelet agents and the use of perioperative peripheral nerve block, modifies surgical delay, stay, readmissions, mortality, suffering delirium and functional status at discharge. MATERIAL AND METHOD: A retrospective observational study of unicenter cohorts of 468 patients with HF, 220 from 2016 (old VC) and 248 from 2019 (new VC). The variables are: intervention in the first 48hours, surgical delay (hours), stay (days), stay less than 15 days, delirium, functional loss at discharge (Barthel prefracture scale less Barthel scale at discharge), readmission at one month, and mortality at admission, month and year. RESULTS: Median age: 87.0 [interquartile range 8.0], mostly women (76.7%). Significantly, with the new VC, there was a greater number of patients operated on in the first 48hours (27,7% vs 36,8% p=0.036), less surgical delay (72.5 [47,5-110,5] vs 64.0 [42,0-88,0] p<0.001), shorter stay (10,0 [7,0-13,0] vs 8,0 [6,0-11,0] p<0.001), greater number of discharges in 15 days (78,2% vs 91,5% p<0.001), lower delirium (54,1% vs 43,5% p=0.023). No significant changes in readmissions, functional loss at discharge, mortality at admission, 3 months or year. CONCLUSIONS: Updating the VC brings benefits to the patient (less surgical delay, equal functional status at discharge with fewer days of admission) and benefits in management (lower admission) without modifying mortality.

Centromere defects, chromosome instability, and cGAS-STING activation in systemic sclerosis.

Centromere defects in Systemic Sclerosis (SSc) have remained unexplored despite the fact that many centromere proteins were discovered in patients with SSc. Here we report that lesion skin fibroblasts from SSc patients show marked alterations in centromeric DNA. SSc fibroblasts also show DNA damage, abnormal chromosome segregation, aneuploidy (only in diffuse cutaneous (dcSSc)) and micronuclei (in all types of SSc), some of which lose centromere identity while retaining centromere DNA sequences. Strikingly, we find cytoplasmic "leaking" of centromere proteins in limited cutaneous SSc (lcSSc) fibroblasts. Cytoplasmic centromere proteins co-localize with antigen presenting MHC Class II molecules, which correlate precisely with the presence of anti-centromere antibodies. CENPA expression and micronuclei formation correlate highly with activation of the cGAS-STING/IFN-ß pathway as well as markers of reactive oxygen species (ROS) and fibrosis, ultimately suggesting a link between centromere alterations, chromosome instability, SSc autoimmunity, and fibrosis.

Functional neuropathology of neonatal hypoxia-ischemia by single-mouse longitudinal electroencephalography.

OBJECTIVE: Neonatal cerebral hypoxia-ischemia (HI) results in symptomatic seizures and long-term neurodevelopmental disability. The Rice-Vannucci model of rodent neonatal HI has been used extensively to examine and translate the functional consequences of acute and chronic HI-induced encephalopathy. Yet, longitudinal electrophysiological characterization of this brain injury model has been limited by the size of the neonatal mouse's head and postnatal maternal dependency. We overcome this challenge by employing a novel method of longitudinal single-mouse electroencephalography (EEG) using chronically implanted subcranial electrodes in the term-equivalent mouse pup. We characterize the neurophysiological disturbances occurring during awake and sleep states in the acute and chronic phases following newborn brain injury. METHODS: C57BL/6 mice underwent long-term bilateral subcranial EEG and electromyographic electrode placement at postnatal day 9 followed by unilateral carotid cauterization and exposure to 40 minutes of hypoxia the following day. EEG recordings were obtained prior, during, and intermittently after the HI procedure from postnatal day 10 to weaning age. Quantitative EEG and fast Fourier transform analysis were used to evaluate seizures, cortical cerebral dysfunction, and disturbances in vigilance states. RESULTS: We observed neonatal HI-provoked electrographic focal and bilateral seizures during or immediately following global hypoxia and most commonly contralateral to the ischemic injury. Spontaneous chronic seizures were not seen. Injured mice developed long-term asymmetric EEG background attenuation in all frequencies and most prominently during non-rapid eye movement (NREM) sleep. HI mice also showed transient impairments in vigilance state duration and transitions during the first 2 days following injury. SIGNIFICANCE: The functional burden of mouse neonatal HI recorded by EEG resembles closely that of the injured human newborn. The use of single-mouse longitudinal EEG in this immature model can advance our understanding of the developmental and pathophysiological mechanisms of neonatal cerebral injury and help translate novel therapeutic strategies against this devastating condition.

The Chromatin Remodeler HELLS: A New Regulator in DNA Repair, Genome Maintenance, and Cancer.

Robust, tightly regulated DNA repair is critical to maintaining genome stability and preventing cancer. Eukaryotic DNA is packaged into chromatin, which has a profound, yet incompletely understood, regulatory influence on DNA repair and genome stability. The chromatin remodeler HELLS (helicase, lymphoid specific) has emerged as an important epigenetic regulator of DNA repair, genome stability, and multiple cancer-associated pathways. HELLS belongs to a subfamily of the conserved SNF2 ATP-dependent chromatin-remodeling complexes, which use energy from ATP hydrolysis to alter nucleosome structure and packaging of chromatin during the processes of DNA replication, transcription, and repair. The mouse homologue, LSH (lymphoid-specific helicase), plays an important role in the maintenance of heterochromatin and genome-wide DNA methylation, and is crucial in embryonic development, gametogenesis, and maturation of the immune system. Human HELLS is abundantly expressed in highly proliferating cells of the lymphoid tissue, skin, germ cells, and embryonic stem cells. Mutations in HELLS cause the human immunodeficiency syndrome ICF (Immunodeficiency, Centromeric instability, Facial anomalies). HELLS has been implicated in many types of cancer, including retinoblastoma, colorectal cancer, hepatocellular carcinoma, and glioblastoma. Here, we review and summarize accumulating evidence highlighting important roles for HELLS in DNA repair, genome maintenance, and key pathways relevant to cancer development, progression, and treatment.

Stoic attitude in patients with cancer from the NEOcoping study: Cross-sectional study.

AIM: Stoicism has been applied to describe a wide range of behaviors in the face of disease and influences an individual's use of coping strategies. This study tested the relationship between stoicism and social support, optimism, psychological distress, and coping strategies in patients with cancer. METHOD: NEOcoping is a multicenter, cross-sectional study. Participants' data were collected using a standardized, self-report form and LSS, MSPSS, Mini-MAC, BSI-18, and LOT-R questionnaires. Linear regression analyses were used to assess the association between stoicism and distress scores in both genders. A total of 932 individuals with non-metastatic, resected cancer were recruited. RESULTS: Males perceived a higher risk of recurrence and toxicity with adjuvant chemotherapy and obtained higher stoic attitude scores than females. Women scored higher on somatization, depression, and anxiety. Patients with high stoicism scores were older and experienced more maladaptive coping (helplessness, anxious preoccupation), and depression, while those with lower stoicism scores had greater perceived social support, optimism, and positive attitude. In both males and females, stoicism correlated negatively with perceived social support, optimism, and positive attitude, and positively with helplessness, anxious preoccupation, and depression. In men, stoicism was directly and negatively associated with social support and optimism, and positively with anxious preoccupation. In women, stoicism was positively associated. In women, stoicism was directly and negatively associated with social support and positively with age and optimism. Stoicism was directly and positively associated with helplessness. DISCUSSION: A stoic attitude was associated with lower social support, reduced optimism, and passive coping strategies (helplessness and anxious preoccupation) in this series of patients with cancer.

SEOM clinical guidelines for the prophylaxis of infectious diseases in cancer patients (2021)

Infections are still a major cause of morbi-mortality in patients with cancer. Some of these infections are preventable through specific measures, such as vaccination or prophylaxis. This guideline aims to summarize the evidence and recommendations for the prevention of infections in cancer patients, devoting special attention to the most prevalent preventable infectious disease. All the evidences will be graded according to The Infectious Diseases Society of America grading system.

Benefits of newborn screening and hematopoietic cell transplant in infantile Krabbe disease.

Infantile Krabbe disease (IKD) can be treated with hematopoietic cell transplantation (HCT) if done during the first weeks of life before symptoms develop. To facilitate this, newborn screening (NBS) has been instituted in 8 US states. An application to add IKD to the recommended NBS panel is currently under review. In this report, the outcomes of newborns with IKD diagnosed through NBS and treated with HCT are presented. The unique challenges associated with NBS for this disease are discussed, including opportunities for earlier diagnosis and streamlining treatment referrals. This is a retrospective review of six infants with IKD detected by NBS who were referred for HCT. The timing from diagnosis to HCT was examined, and both HCT and neurodevelopmental outcomes are described. Neurologic testing before HCT revealed evidence of active IKD in all infants. All underwent HCT between 24 and 40 days of age, were successfully engrafted, and are alive 30 to 58 months later (median, 47.5 months). All are gaining developmental milestones albeit at a slower pace than unaffected age-matched peers. Gross motor function is most notably affected. NBS for these patients enabled early access to HCT, the only currently available treatment of infants with IKD. All children are alive and have derived developmental and neurologic benefits from timely HCT. Long-term follow up is ongoing. Optimization of HCT and further development of emerging therapies, all of which must be delivered early in life, are expected to further improve outcomes of infants with IKD.

The role of the histone H3 variant CENPA in prostate cancer.

Overexpression of centromeric proteins has been identified in a number of human malignancies, but the functional and mechanistic contributions of these proteins to disease progression have not been characterized. The centromeric histone H3 variant centromere protein A (CENPA) is an epigenetic mark that determines centromere identity. Here, using an array of approaches, including RNA-sequencing and ChIP-sequencing analyses, immunohistochemistry-based tissue microarrays, and various cell biology assays, we demonstrate that CENPA is highly overexpressed in prostate cancer in both tissue and cell lines and that the level of CENPA expression correlates with the disease stage in a large cohort of patients. Gain-of-function and loss-of-function experiments confirmed that CENPA promotes prostate cancer cell line growth. The results from the integrated sequencing experiments suggested a previously unidentified function of CENPA as a transcriptional regulator that modulates expression of critical proliferation, cell-cycle, and centromere/kinetochore genes. Taken together, our findings show that CENPA overexpression is crucial to prostate cancer growth.

Early developmental electroencephalography abnormalities, neonatal seizures, and induced spasms in a mouse model of tuberous sclerosis complex.

OBJECTIVE: Tuberous sclerosis complex (TSC) is one of the most common genetic causes of epilepsy. Seizures in TSC typically first present in infancy or early childhood, including focal seizures and infantile spasms. Infantile spasms in TSC are particularly characteristic in its strong responsiveness to vigabatrin. Although a number of mouse models of epilepsy in TSC have been described, there are very limited electroencephalographic (EEG) or seizure data during the preweanling neonatal and infantile-equivalent mouse periods. Tsc1GFAP CKO mice are a well-characterized mouse model of epilepsy in TSC, but whether these mice have seizures during early development has not been documented. The objective of this study was to determine whether preweanling Tsc1GFAP CKO mice have developmental EEG abnormalities or seizures, including spasms. METHODS: Longitudinal video-EEG and electromyographic recordings were performed serially on Tsc1GFAP CKO and control mice from postnatal days 9-21 and analyzed for EEG background abnormalities, sleep-wake vigilance states, and spontaneous seizures. Spasms were also induced with varying doses of N-methyl-D-aspartate (NMDA). RESULTS: The interictal EEG of Tsc1GFAP CKO mice had excessive discontinuity and slowing, suggesting a delayed developmental progression compared with control mice. Tsc1GFAP CKO mice also had increased vigilance state transitions and fragmentation. Tsc1GFAP CKO mice had spontaneous focal seizures in the early neonatal period and a reduced threshold for NMDA-induced spasms, but no spontaneous spasms were observed. SIGNIFICANCE: Neonatal Tsc1GFAP CKO mice recapitulate early developmental aspects of EEG abnormalities, focal seizures, and an increased propensity for spasms. This mouse model may be useful for early mechanistic and therapeutic studies of epileptogenesis in TSC.

Is the HERV-K HML-2 Xq21.33, an endogenous retrovirus mutated by gene conversion of chromosome X in a subset of African populations, associated with human breast cancer?

The human endogenous retroviruses HERV-K HML-2 have been considered a possible cause of human breast cancer (BrC). A HERV-K HML-2 fully intact provirus Xq21.33 was recently identified in some West African people. We used PCR technology to search for the Xq21.33 provirus in DNA from Nigerian women with BrC and controls. to see if Xq21.33 plays any role in predisposing to BrC. This provirus was detected in 27 of 216 (12.5%) women with BrC and in 22 of 219 (10.0%) controls. These results were not statistically significant. The prevalence of provirus in premenopausal control women 44 years or younger [18/157 (11.46%)} vs women with BrC [12/117 (10.26%)] showed no statistical difference. The prevalence of virus in postmenopausal control women > 45 yrs. was 7.4% (4/54) vs 15.31% (15/98) in postmenopausal women with BrC. These changes were not statistically significant at <.05, but the actual p value of <.0.079, suggests that Xq21.33 might play some role in predisposing to BrC in postmenopausal women. Provirus was present in Ghanaian women (6/87), in 1/6 Pygmy populations and in African American men (4/45) and women (6/68), but not in any Caucasian women (0/109). Two BrC cell lines (HCC 70 and DT22) from African American women had Xq21.33. Env regions of the virus which differed by 2-3 SNPs did not alter the protein sequence of the virus. SNP at 5730 and 8529 were seen in all persons with provirus, while 54% had an additional SNP at 7596.Two Nigerian women and 2 Ghanaian women had additional unusual SNPs. Homozygosity was seen in (5/27) BrC and (2/22) control women. The genetic variation and homozygosity patterns suggested that there was gene conversion of this X chromosome associated virus. The suggestive finding in this preliminary data of possible increased prevalence of Xq21.33 provirus in post-menopausal Nigerian women with BrC should be clarified by a more statistically powered study sample to see if postmenopausal African and/or African American women carriers of Xq21.33 might show increased risk of BrC. The implication of finding such a link would be the development of antiretroviral drugs that might aid in preventing BrC in Xq21.33+ women.

The Genomic Landscape of Centromeres in Cancers.

Centromere genomics remain poorly characterized in cancer, due to technologic limitations in sequencing and bioinformatics methodologies that make high-resolution delineation of centromeric loci difficult to achieve. We here leverage a highly specific and targeted rapid PCR methodology to quantitatively assess the genomic landscape of centromeres in cancer cell lines and primary tissue. PCR-based profiling of centromeres revealed widespread heterogeneity of centromeric and pericentromeric sequences in cancer cells and tissues as compared to healthy counterparts. Quantitative reductions in centromeric core and pericentromeric markers (α-satellite units and HERV-K copies) were observed in neoplastic samples as compared to healthy counterparts. Subsequent phylogenetic analysis of a pericentromeric endogenous retrovirus amplified by PCR revealed possible gene conversion events occurring at numerous pericentromeric loci in the setting of malignancy. Our findings collectively represent a more comprehensive evaluation of centromere genetics in the setting of malignancy, providing valuable insight into the evolution and reshuffling of centromeric sequences in cancer development and progression.

Secreted nuclear protein DEK regulates hematopoiesis through CXCR2 signaling.

The nuclear protein DEK is an endogenous DNA-binding chromatin factor regulating hematopoiesis. DEK is one of only 2 known secreted nuclear chromatin factors, but whether and how extracellular DEK regulates hematopoiesis is not known. We demonstrated that extracellular DEK greatly enhanced ex vivo expansion of cytokine-stimulated human and mouse hematopoietic stem cells (HSCs) and regulated HSC and hematopoietic progenitor cell (HPC) numbers in vivo and in vitro as determined both phenotypically (by flow cytometry) and functionally (through transplantation and colony formation assays). Recombinant DEK increased long-term HSC numbers and decreased HPC numbers through a mechanism mediated by the CXC chemokine receptor CXCR2 and heparan sulfate proteoglycans (HSPGs) (as determined utilizing Cxcr2-/- mice, blocking CXCR2 antibodies, and 3 different HSPG inhibitors) that was associated with enhanced phosphorylation of ERK1/2, AKT, and p38 MAPK. To determine whether extracellular DEK required nuclear function to regulate hematopoiesis, we utilized 2 mutant forms of DEK: one that lacked its nuclear translocation signal and one that lacked DNA-binding ability. Both altered HSC and HPC numbers in vivo or in vitro, suggesting the nuclear function of DEK is not required. Thus, DEK acts as a hematopoietic cytokine, with the potential for clinical applicability.

Structural variation of centromeric endogenous retroviruses in human populations and their impact on cutaneous T-cell lymphoma, Sézary syndrome, and HIV infection.

BACKGROUND: Human Endogenous Retroviruses type K HML-2 (HK2) are integrated into 117 or more areas of human chromosomal arms while two newly discovered HK2 proviruses, K111 and K222, spread extensively in pericentromeric regions, are the first retroviruses discovered in these areas of our genome. METHODS: We use PCR and sequencing analysis to characterize pericentromeric K111 proviruses in DNA from individuals of diverse ethnicities and patients with different diseases. RESULTS: We found that the 5' LTR-gag region of K111 proviruses is missing in certain individuals, creating pericentromeric instability. K111 deletion (-/- K111) is seen in about 15% of Caucasian, Asian, and Middle Eastern populations; it is missing in 2.36% of African individuals, suggesting that the -/- K111 genotype originated out of Africa. As we identified the -/-K111 genotype in Cutaneous T-cell lymphoma (CTCL) cell lines, we studied whether the -/-K111 genotype is associated with CTCL. We found a significant increase in the frequency of detection of the -/-K111 genotype in Caucasian patients with severe CTCL and/or Sézary syndrome (n = 35, 37.14%), compared to healthy controls (n = 160, 15.6%) [p = 0.011]. The -/-K111 genotype was also found to vary in HIV-1 infection. Although Caucasian healthy individuals have a similar frequency of detection of the -/- K111 genotype, Caucasian HIV Long-Term Non-Progressors (LTNPs) and/or elite controllers, have significantly higher detection of the -/-K111 genotype (30.55%; n = 36) than patients who rapidly progress to AIDS (8.5%; n = 47) [p = 0.0097]. CONCLUSION: Our data indicate that pericentromeric instability is associated with more severe CTCL and/or Sézary syndrome in Caucasians, and appears to allow T-cells to survive lysis by HIV infection. These findings also provide new understanding of human evolution, as the -/-K111 genotype appears to have arisen out of Africa and is distributed unevenly throughout the world, possibly affecting the severity of HIV in different geographic areas.

The HERV-K accessory protein Np9 controls viability and migration of teratocarcinoma cells.

Human endogenous retroviruses are remnants of ancient germline infections that make up approximately 8% of the modern human genome. The HERV-K (HML-2) family is one of the most recent entrants into the human germline, these viruses appear to be transcriptionally active, and HERV-K viral like particles (VLPs) are found in cell lines from a number of human malignancies. HERV-K VLPs were first found to be produced in teratocarcinoma cell lines, and since then teratocarcinoma has been thought of as the classical model for HERV-Ks, with the NCCIT teratocarcinoma cell line particularly known to produce VLPs. Treatment for teratocarcinoma has progressed since its discovery, with improved prognosis for patients. Since the introduction of platinum based therapy, first year survival has greatly improved even with disseminated disease; however, it is estimated that 20% to 30% of patients present with metastatic germ cell tumor relapse following initial treatments. Also, the toxicity associated with the use of chemotherapeutic agents used to treat germ cell tumors is still a major concern. In this study, we show that the depletion of the HERV-K accessory protein Np9 increases the sensitivity of NCCIT teratocarcinoma cells to bleomycin and cisplatin. While decreasing the expression of Np9 had only a modest effect on the baseline viability of the cells, the reduced expression of Np9 increased the sensitivity of the teratocarcinoma cells to environmental (serum starvation) and chemical (chemotherapeutic) stresses. Np9 is also essential to the migration of NCCIT teratocarcinoma cells: in a wound closure assay, reduced expression of Np9 resulted in cells migrating into the wound at a slower rate, whereas reintroduction of Np9 resulted in NCCIT cells migrating back into the wound in a manner similar to the control. These findings support the implication that the HERV-K accessory protein Np9 has oncogenic potential.