Sickle Cell Hemoglobin Genotypes Affect Malaria Parasite Growth and Correlate with Exosomal miR-451a and let-7i-5p Levels.

Malaria affects a significant portion of the global population, with 247 million cases in 2021, primarily in Africa. However, certain hemoglobinopathies, such as sickle cell trait (SCT), have been linked to lower mortality rates in malaria patients. Hemoglobin (Hb) mutations, including HbS and HbC, can cause sickle cell disease (SCD) when both alleles are inherited (HbSS and HbSC). In SCT, one allele is inherited and paired with a normal allele (HbAS, HbAC). The high prevalence of these alleles in Africa may be attributed to their protective effect against malaria. Biomarkers are crucial for SCD and malaria diagnosis and prognosis. Studies indicate that miRNAs, specifically miR-451a and let-7i-5p, are differentially expressed in HbSS and HbAS compared to controls. Our research examined the levels of exosomal miR-451a and let-7i-5p in red blood cells (RBCs) and infected red blood cells (iRBCs) from multiple sickle Hb genotypes and their impact on parasite growth. We assessed exosomal miR-451a and let-7i-5p levels in vitro in RBC and iRBC supernatants. Exosomal miRNAs exhibited distinct expression patterns in iRBCs from individuals with different sickle Hb genotypes. Additionally, we discovered a correlation between let-7i-5p levels and trophozoite count. Exosomal miR-451a and let-7i-5p could modulate SCD and malaria severity and serve as potential biomarkers for malaria vaccines and therapies.

Psychiatric Treatment and Repeat Suicide Attempts Among Adults With Substance Use, by HIV Status, United States, 2014-2020.

OBJECTIVES: The association among psychiatric treatment history, HIV, and suicide reattempts among people starting treatment for substance use is not well understood. The objective of this study was to describe, by HIV status, the risk and protective factors associated with suicide reattempts among adults seeking treatment for substance use. METHODS: The study included 340 390 US adult residents aged ≥18 years in the Addiction Severity Index-Multimedia Version network from January 1, 2014, through December 31, 2020. We used adjusted logistic regression models to estimate strength of association between prior psychiatric treatment, HIV status, and sociodemographic factors and suicide reattempts within 30 days of treatment evaluation. RESULTS: Adults who had been prescribed psychiatric medication were less likely to have a recent suicide reattempt (adjusted odds ratio [aOR] = 0.8; 95% CI, 0.7-0.8) than adults with no prescription history. Adjusted models found similar protective effects between psychiatric treatment and suicide reattempts among adults reporting abuse, mental illness, injection drug use, and limited activity because of a medical condition. Conversely, the following were associated with recent suicide reattempts: being male (aOR = 1.4; 95% CI, 1.3-1.5), having a high school education/GED (General Educational Development) or less (aOR = 1.2; 95% CI, 1.1-1.2), being single (aOR = 1.2; 95% CI, 1.1-1.3), experiencing a pain problem (aOR = 1.2; 95% CI, 1.2-1.3), and not being referred to substance use treatment by court (aOR = 3.4; 95% CI, 3.2-3.7). CONCLUSIONS: A history of prescribed psychiatric medication is significantly associated with a reduced risk for suicide reattempts among adults seeking substance use treatment. Clinicians should consider incorporating mental health and suicide assessments into substance use treatment plans.

MicroRNAs miR-451a and Let-7i-5p Profiles in Circulating Exosomes Vary among Individuals with Different Sickle Hemoglobin Genotypes and Malaria.

Sickle cell disease (SCD) occurs when two alleles of mutated hemoglobin (HbS or HbC) are inherited (HbSS and HbSC) rather than one (HbAS or HbAC), which indicates a person carries the sickle cell trait. The high prevalence of these two alleles in Africa have been associated with reduced malaria susceptibility. Recent in vitro research has been shown that microRNAs (miRNAs) miR-451a and let-7i-5p are differentially expressed in HbSS erythrocytes compared to healthy controls (HbAA) and are overexpressed in Plasmodium-infected malaria erythrocytes. However, these miRNAs have not been fully examined in the plasma of people with different sickle hemoglobin genotypes. Plasma circulating miRNAs are commonly encapsulated in extracellular vesicles, such as exosomes, and are thought to play a role in disease development. Circulating exosomal miR-451a and let-7i-5p were quantified from individuals with various hemoglobin genotypes (HbAA, HbAS, HbAC, HbSS, HbSC, and HbCC) with (+) and without (-) malaria. The results showed a higher level of exosomal let-7i-5p and miR-451a in HbSS-. Exosomal let-7i-5p and miR-451a levels were lower in HbSS+ compared to other genotypes. Based on the area under the curve (AUC) of the Receiver Operating Characteristics (ROCs), both exosomal miRNAs may be useful disease biomarkers for SCD with malaria. Finally, miR-451a and let-7i-5p modulate genes involved in inflammation, making them potential biomarkers of pathogenesis for both diseases.

Association of Self-Reported Depression and Anger with Law Enforcement Officers' Physical Abuse of Black Men in 4 Georgia Counties, 2011.

INTRODUCTION: The association between the behavioral affect of black men and law enforcement officers' physical abuse of those men is not well-understood. This analysis measures the association between self-reported negative affect behavior (anger or depression) by the men and physical abuse by law enforcement officers, controlling for demographic and behavioral attributes. METHODS: A single point-in-time cross-sectional survey was conducted in 2011 through random-digit telephone dialing among a sample of English-speaking black men aged 18-65 years in 4 Georgia (USA) counties. Associations among the outcomes, self-reported history of physical abuse by law enforcement officers, and the predictor variables of interest (self-reported anger or depression) was conducted through multivariable logistic regression. Other independent variables of interest measured were age; country of origin; parental country of origin; education; income; employment status; previous residency in a juvenile, jail, or prison facility; coping styles; and self-reported gender role and racism stress levels. RESULTS: Of the 633 survey participants who had interacted with law enforcement officers within the past 5 years, 129 (20.4%) reported physical abuse by law enforcement officers. Three factors had statistically significant, independent associations with reported law enforcement officer physical abuse: high levels of depression stratified by often or sometimes coping with stress through anger (adjusted odds ratio [aOR] = 4.9; 95% confidence interval [CI]: 1.4-16.9), previous residency in a jail or prison (aOR = 2.3; 95% CI: 1.8-3.1), and higher levels of exposure to racism (aOR [high levels of racism] = 15.0; 95% CI: 6.7-33.7 and aOR [medium levels of racism] = 6.5; 95% CI: 3.4-12.3). CONCLUSION: Cohort studies are needed to determine if a black man's negative coping style, history of incarceration or exposure to racism is causally related to his history of physical abuse by a law enforcement officer.

Risk Factors for and Trends in Isoniazid Monoresistance at Diagnosis of Tuberculosis-United States, 1993-2016.

CONTEXT: Resistance to isoniazid (INH) only (monoresistance), with drug susceptibility to rifampin, pyrazinamide, and ethambutol at diagnosis of tuberculosis (TB) disease, can increase the length of treatment. OBJECTIVE: To describe US trends in INH monoresistance and associated patient characteristics. DESIGN: We performed trend and cross-sectional analyses of US National Tuberculosis Surveillance System surveillance data. We used Joinpoint regression to analyze annual trends in INH monoresistance and logistic regression to identify patient characteristics associated with INH monoresistance. PARTICIPANTS: Culture-positive cases reported to National Tuberculosis Surveillance System during 1993-2016 with drug susceptibility test results to INH, rifampin, pyrazinamide, and ethambutol. MAIN OUTCOME MEASURES: (1) Trends in INH monoresistance; (2) odds ratios for factors associated with INH monoresistance. RESULTS: Isoniazid monoresistance increased significantly from 4.1% of all TB cases in 1993 to 4.9% in 2016. Among US-born patients, INH monoresistance increased significantly from 2003 onward (annual percentage change = 2.8%; 95% confidence interval: 1.4-4.2). During 2003-2016, US-born persons with INH-monoresistant TB were more likely to be younger than 65 years; to be Asian; to be human immunodeficiency virus-infected; or to be a correctional facility resident at the time of diagnosis. Among non-US-born persons, INH resistance did not change significantly during 1993-2016 (annual percentage change = -0.3%; 95% confidence interval: -0.7 to 0.2) and was associated with being aged 15 to 64 years; being Asian, black, or Hispanic; or having a previous history of TB. CONCLUSIONS: INH-monoresistant TB has been stable since 1993 among non-US-born persons; it has increased 2.8% annually among US-born persons during 2003-2016. Reasons for this increase should be further investigated.

Factors Associated With Latent Tuberculosis Infection Treatment Failure Among Patients With Commercial Health Insurance-United States, 2005-2016.

CONTEXT: Approximately 80% of US tuberculosis (TB) cases verified during 2015-2016 were attributed to untreated latent TB infection (LTBI). Identifying factors associated with LTBI treatment failure might improve treatment effectiveness. OBJECTIVE: To identify patients with indicators of isoniazid (INH) LTBI treatment initiation, completion, and failure. METHODS: We searched inpatient and outpatient claims for International Classification of Diseases (Ninth and Tenth Revisions), National Drug, and Current Procedural Terminology codes. We defined treatment completion as 180 days or more of INH therapy during a 9-month period. We defined LTBI treatment failure as an active TB disease diagnosis more than 1 year after starting LTBI treatment among completers and used exact logistic regression to model possible differences between groups. Among treatment completers, we matched 1 patient who failed treatment with 2 control subjects and fit regression models with covariates documented on medical claims paid 6 months or less before INH treatment initiation. PARTICIPANTS: Commercially insured US patients in a large commercial database with insurance claims paid during 2005-2016. MAIN OUTCOME MEASURES: (1) Trends in treatment completion; (2) odds ratios (ORs) for factors associated with treatment completion and treatment failure. RESULTS: Of 21 510 persons who began LTBI therapy during 2005-2016, 10 725 (49.9%) completed therapy. Treatment noncompletion is associated with those younger than 45 years, living in the Northeast or South Census regions, and women. Among persons who completed treatment, 30 (0.3%) progressed to TB disease. Diagnoses of rheumatoid arthritis during the 6 months before treatment initiation and being aged 65 years or older (reference: ages 0-24 years) were significantly associated with INH LTBI treatment failure (adjusted exact OR = 5.1; 95% CI, 1.2-28.2; and adjusted exact OR = 5.1; 95% CI, 1.2-25.3, respectively). CONCLUSION: Approximately 50% of persons completed INH LTBI therapy, and of those, treatment failure was associated with rheumatoid arthritis and persons 65 years or older among a cohort of US LTBI patients with commercial health insurance.

Mental illness, physical and sexual abuse associated with HIV risk behaviors among adults evaluated for substance use and treatment planning in the National Addictions Vigilance Intervention and Prevention Program - United States, 2014-2019.

Background: The association between sexual and physical abuse history, mental illness, and HIV risk behaviors among persons starting treatment for substance use is not well-understood. Methods: The study population included 216,877 US residents in the National Addictions Vigilance Intervention and Prevention Program (NAVIPPRO) from January 1, 2014-December 31, 2019. We used logistic regression models to estimate strength of pairwise association between mental illness, sexual or physical abuse histories and each of 3 HIV risk outcomes. Results: Compared with no history of physical or sexual abuse, a history of sexual and physical abuse combined was associated with greater odds ratios for: (1) injection drug use among persons without a history of mental illness (odds ratio [OR] 2.4; 95% confidence interval [CI]: 2.3-2.6) than among persons with a history of mental illness (OR 2.0; 95% CI: 1.9-2.0); (2) prostitution conviction among persons without mental illness (OR 3.8; 95% CI: 2.8-5.1) than among persons with mental illness (OR 2.8; 95% CI: 2.4-3.4); and (3) and ≥2 sex partners within the past 30 days with a history of mental illness (OR 1.3; 95% CI: 1.2-1.4). Conclusions: The findings imply that efforts to reduce HIV risk behaviors during and after substance use treatment can be improved by considering the patient's history of physical or sexual abuse and mental illness when providing care.

Age-Period-Cohort Analyses of Tuberculosis Incidence Rates by Nativity, United States, 1996-2016.

OBJECTIVES: To assess changes in US tuberculosis (TB) incidence rates by age, period, and cohort effects, stratified according to race/ethnicity and nativity. METHODS: We used US National Tuberculosis Surveillance System data for 1996 to 2016 to estimate trends through age-period-cohort models. RESULTS: Controlling for cohort and period effects indicated that the highest rates of TB incidence occurred among those 0 to 5 and 20 to 30 years of age. The incidence decreased by age for successive birth cohorts. There were greater estimated annual percentage decreases among US-born individuals (-7.3%; 95% confidence interval [CI] = -7.5, -7.1) than among non-US-born individuals (-4.3%; 95% CI = -4.5, -4.1). US-born individuals older than 25 years exhibited the largest decreases, a pattern that was not reflected among non-US-born adults. In the case of race/ethnicity, the greatest decreases by nativity were among US-born Blacks (-9.3%; 95% CI = -9.6, -9.1) and non-US-born Hispanics (-5.7%; 95% CI = -6.0, -5.5). CONCLUSIONS: TB has been decreasing among all ages, races and ethnicities, and consecutive cohorts, although these decreases are less pronounced among non-US-born individuals.

Hematological Differences among Malaria Patients in Rural and Urban Ghana.

BACKGROUND: Scarce studies have addressed hematological differences of malaria in urban and rural regions. METHODS: Full or complete blood cell counts from 46 and 75 individuals (age range from < 1 to 92 years) with uncomplicated malaria infection living in urban (Accra) and rural (Dodowa) Ghana, respectively, were assessed. Sickle cell trait and patients were excluded from the study. RESULTS: Between overall groups, patients from Accra had significantly lower parasite count (p < 0.0001) and granulocyte number (p = 0.026). Children in Accra had a significantly lower parasitemia (p = 0.0013), hemoglobin (p = 0.0254), platelet count (p = 0.0148) and red blood cell levels (p = 0.0080) when compared with the children of Dodowa. In adults, mean cell hemoglobin (p = 0.0086) and parasite count (p < 0.0001) were significantly higher in Dodowa. CONCLUSION: These results indicate that children living in urban setting may experience a greater anemic effect to malaria as compared with those living in a rural setting.

Reproducible Research Practices and Transparency across the Biomedical Literature.

There is a growing movement to encourage reproducibility and transparency practices in the scientific community, including public access to raw data and protocols, the conduct of replication studies, systematic integration of evidence in systematic reviews, and the documentation of funding and potential conflicts of interest. In this survey, we assessed the current status of reproducibility and transparency addressing these indicators in a random sample of 441 biomedical journal articles published in 2000-2014. Only one study provided a full protocol and none made all raw data directly available. Replication studies were rare (n = 4), and only 16 studies had their data included in a subsequent systematic review or meta-analysis. The majority of studies did not mention anything about funding or conflicts of interest. The percentage of articles with no statement of conflict decreased substantially between 2000 and 2014 (94.4% in 2000 to 34.6% in 2014); the percentage of articles reporting statements of conflicts (0% in 2000, 15.4% in 2014) or no conflicts (5.6% in 2000, 50.0% in 2014) increased. Articles published in journals in the clinical medicine category versus other fields were almost twice as likely to not include any information on funding and to have private funding. This study provides baseline data to compare future progress in improving these indicators in the scientific literature.

Pomegranate extract inhibits the bone metastatic growth of human prostate cancer cells and enhances the in vivo efficacy of docetaxel chemotherapy.

BACKGROUND: Docetaxel treatment is the only first-line chemotherapy with a survival benefit in metastatic castration-resistant prostate cancer (PCa). Nonetheless, most patients become docetaxel resistant and inevitably progress with no cure. In this study, we investigated the potential of pomegranate extract (PE) in targeting metastatic castration-resistant PCa and improving docetaxel chemotherapy. METHODS: The in vitro and in vivo effect of POMx, a PE formula currently approved for clinical trials, in metastatic castration-resistant PCa cells was evaluated in experimental models. RESULTS: We demonstrated that POMx exhibited potent in vitro cytotoxicity in metastatic castration-resistant PCa cells. Mechanistic studies identified survivin as a novel molecular target that may mediate the anti-cancer activity of POMx, presumably through the inhibition of signal transducer and activator of transcription 3. The in vivo administration of POMx treatment effectively inhibited survivin, induced apoptosis, retarded C4-2 tumor growth in skeleton and significantly enhanced the efficacy of docetaxel in athymic nude mice. CONCLUSION: These results provide the first preclinical evidence that POMx may be effective in treating metastatic castration-resistant PCa and enhancing the efficacy of docetaxel chemotherapy. Prostate © 2013 Wiley Periodicals, Inc.

Genistein enhances the efficacy of cabazitaxel chemotherapy in metastatic castration-resistant prostate cancer cells.

BACKGROUND: Cabazitaxel (Jevtana) has been approved for the treatment of metastatic castration-resistant prostate cancer (mCRPC). However, most patients progress and become chemoresistant, which remains a major challenge in the management of advanced PCa. In this study, we investigated whether genistein, an isoflavone abundant in soy products, could sensitize mCRPC cells to cabazitaxel treatment in experimental models. METHODS: The in vitro and in vivo effect of genistein in enhancing the response of mCRPC cells to cabazitaxel chemotherapy was evaluated in experimental models. RESULTS: Genistein increases the expression of pro-apoptotic protein Bax, activates apoptotic signals, and enhances the response to cabazitaxel treatment in mCRPC cells. In a PC3-luciferase xenograft model, the combined treatment with genistein and cabazitaxel significantly retarded the growth of mCRPC when compared to vehicle control, cabazitaxel, or genistein. Tissue staining confirmed the in vivo effect of genistein on the induction of Bax and activation of apoptosis. CONCLUSION: This study provided the first preclinical evidence supporting that genistein could be beneficial in improving cabazitaxel chemotherapy in mCRPC.

Epidermal growth factor promotes protein degradation of epithelial protein lost in neoplasm (EPLIN), a putative metastasis suppressor, during epithelial-mesenchymal transition.

Aberrant expression of EGF receptors has been associated with hormone-refractory and metastatic prostate cancer (PCa). However, the molecular mechanism for EGF signaling in promoting PCa metastasis remains elusive. Using experimental models of PCa metastasis, we demonstrated that EGF could induce robust epithelial-mesenchymal transition (EMT) and increase invasiveness. Interestingly, EGF was found to be capable of promoting protein turnover of epithelial protein lost in neoplasm (EPLIN), a putative suppressor of EMT and tumor metastasis. Mechanistic study revealed that EGF could activate the phosphorylation, ubiquitination, and degradation of EPLIN through an extracellular signal-regulated kinase 1/2 (ERK1/2)-dependent signaling cascade. Pharmacological inhibition of the ERK1/2 pathway effectively antagonized EGF-induced EPLIN degradation. Two serine residues, i.e. serine 362 and serine 604, were identified as putative ERK1/2 phosphorylation sites in human EPLIN, whose point mutation rendered resistance to EGF-induced protein turnover. This study elucidated a novel molecular mechanism for EGF regulation of EMT and invasiveness in PCa cells, indicating that blockade of EGF signaling could be beneficial in preventing and retarding PCa metastasis at early stages.

PDGF upregulates Mcl-1 through activation of ß-catenin and HIF-1α-dependent signaling in human prostate cancer cells.

BACKGROUND: Aberrant platelet derived growth factor (PDGF) signaling has been associated with prostate cancer (PCa) progression. However, its role in the regulation of PCa cell growth and survival has not been well characterized. METHODOLOGY/PRINCIPAL FINDINGS: Using experimental models that closely mimic clinical pathophysiology of PCa progression, we demonstrated that PDGF is a survival factor in PCa cells through upregulation of myeloid cell leukemia-1 (Mcl-1). PDGF treatment induced rapid nuclear translocation of ß-catenin, presumably mediated by c-Abl and p68 signaling. Intriguingly, PDGF promoted formation of a nuclear transcriptional complex consisting of ß-catenin and hypoxia-inducible factor (HIF)-1α, and its binding to Mcl-1 promoter. Deletion of a putative hypoxia response element (HRE) within the Mcl-1 promoter attenuated PDGF effects on Mcl-1 expression. Blockade of PDGF receptor (PDGFR) signaling with a pharmacological inhibitor AG-17 abrogated PDGF induction of Mcl-1, and induced apoptosis in metastatic PCa cells. CONCLUSIONS/SIGNIFICANCE: Our study elucidated a crucial survival mechanism in PCa cells, indicating that interruption of the PDGF-Mcl-1 survival signal may provide a novel strategy for treating PCa metastasis.

Genetic polymorphisms linked to susceptibility to malaria.

The influence of host genetics on susceptibility to Plasmodium falciparum malaria has been extensively studied over the past twenty years. It is now clear that malaria parasites have imposed strong selective forces on the human genome in endemic regions. Different genes have been identified that are associated with different malaria related phenotypes. Factors that promote severity of malaria include parasitaemia, parasite induced inflammation, anaemia and sequestration of parasitized erythrocytes in brain microvasculature.Recent advances in human genome research technologies such as genome-wide association studies (GWAS) and fine genotyping tools have enabled the discovery of several genetic polymorphisms and biomarkers that warrant further study in host-parasite interactions. This review describes and discusses human gene polymorphisms identified thus far that have been shown to be associated with susceptibility or resistance to P. falciparum malaria. Although some polymorphisms play significant roles in susceptibility to malaria, several findings are inconclusive and contradictory and must be considered with caution. The discovery of genetic markers associated with different malaria phenotypes will help elucidate the pathophysiology of malaria and enable development of interventions or cures. Diversity in human populations as well as environmental effects can influence the clinical heterogeneity of malaria, thus warranting further investigations with a goal of developing new interventions, therapies and better management against malaria.

Vascular endothelial growth factor regulates myeloid cell leukemia-1 expression through neuropilin-1-dependent activation of c-MET signaling in human prostate cancer cells.

BACKGROUND: Myeloid cell leukemia-1 (Mcl-1) is a member of the Bcl-2 family, which inhibits cell apoptosis by sequestering pro-apoptotic proteins Bim and Bid. Mcl-1 overexpression has been associated with progression in leukemia and some solid tumors including prostate cancer (PCa). However, the regulatory mechanism for Mcl-1 expression in PCa cells remains elusive. RESULTS: Immunohistochemical analyses revealed that Mcl-1 expression was elevated in PCa specimens with high Gleason grades and further significantly increased in bone metastasis, suggesting a pivotal role of Mcl-1 in PCa metastasis. We further found that vascular endothelial growth factor (VEGF) is a novel regulator of Mcl-1 expression in PCa cells. Inhibition of endogenous Mcl-1 induced apoptosis, indicating that Mcl-1 is an important survival factor in PCa cells. Neuropilin-1 (NRP1), the "co-receptor" for VEGF165 isoform, was found to be highly expressed in PCa cells, and indispensible in the regulation of Mcl-1. Intriguingly, VEGF165 promoted physical interaction between NRP1 and hepatocyte growth factor (HGF) receptor c-MET, and facilitated c-MET phosphorylation via a NRP1-dependent mechanism. VEGF165 induction of Mcl-1 may involve rapid activation of Src kinases and signal transducers and activators of transcription 3 (Stat3). Importantly, NRP1 overexpression and c-MET activation were positively associated with progression and bone metastasis in human PCa specimens and xenograft tissues. CONCLUSIONS: This study demonstrated that Mcl-1 overexpression is associated with PCa bone metastasis. Activation of VEGF165-NRP1-c-MET signaling could confer PCa cells survival advantages by up-regulating Mcl-1, contributing to PCa progression.

BKM1740, an acyl-tyrosine bisphosphonate amide derivative, inhibits the bone metastatic growth of human prostate cancer cells by inducing apoptosis.

PURPOSE: Survivin overexpression has been associated with an unfavorable outcome in human PCa; however, its role in metastasis remains elusive. We aim to (a) evaluate the clinical implications of survivin expression in PCa bone metastasis; (b) determine in vivo efficacy of BKM1740, a small-molecule compound, against PCa skeletal growth and survival; and (c) investigate molecular mechanism by which BKM1740 augments apoptosis in bone metastatic PCa cells. EXPERIMENTAL DESIGN: Survivin expression was analyzed in PCa specimens and experimental models. Bone metastatic C4-2 and ARCaP(M) cell lines were used to evaluate the in vitro effects of BKM1740 and molecular mechanism for the induction of apoptosis. C4-2 cells were grown intratibially in athymic nude mice to evaluate the in vivo efficacy of BKM1740. Tumor growth in mouse bone was assessed by serum prostate-specific antigen and radiography and confirmed by immunohistochemical analyses. RESULTS: Survivin expression is positively associated with clinical PCa bone metastasis. BKM1740 induced apoptosis in PCa cells by repressing survivin. Mice with established C4-2 tumors in tibia showed a marked decrease in serum prostate-specific antigen and much improved bone architecture radiographically after treatment with BKM1740. Immunohistochemical assays of mouse tumor samples confirmed that the in vivo effects were mediated by inhibition of survivin and induction of apoptosis. CONCLUSIONS: Survivin expression is associated with PCa bone metastasis. BKM1740 treatment specifically inhibited survivin and induced apoptosis in vitro and was efficacious in retarding PCa skeletal growth in a mouse model. BKM1740 is a promising small-molecule compound that could be used to treat PCa bone metastasis.

Expansion of Hepatic and Hematopoietic Stem Cells Utilizing Mouse Embryonic Liver Explants.

Ex vivo embryonic liver explant culture is a novel and attractive approach to obtain abundant hepatic and hematopoietic stem cells. Gene therapy of autologous hepatic and hematopoietic stem cells represents an alternative therapeutic approach to liver transplantation for genetic and metabolic disorders. In this study we characterize the growth and differentiation of hepatic stem cells utilizing embryonic liver cultures. Day 9.5 liver buds are microdissected and cultured under specific conditions. Modulation of growth conditions by addition of hepatocyte growth factor, Flt-3 ligand, and stem cell factor leads to enrichment of hepatic progenitor cells in embryonic liver explants. Under these conditions, we also demonstrate the role of a novel marker PRAJA-1 to identify hepatic stem cells and transitional hepatocytes. Utilization of dexamethasone enhanced pseudolobule formation with increased hepatocytic and biliary differentiation. Transforming growth factor-ß leads to enrichment of biliary cells in the culture. Gut formation is enhanced in the presence of interleukin-3 and blood formation by increasing the mesodermal tissue in these cultures. We also show increased retroviral-mediated expression of the green fluorescent protein expression in the expanded hepatic and hematopoietic stem cells under different culture conditions. Thus, the embryonic liver explant culture is an attractive source for hepatic progenitors and is a possible step towards generating nontumorigenic immortalized hepatocytes with possible transplantation applications.