Genome-wide association studies are identifying novel Alzheimer's disease (AD) risk factors. Elucidating the mechanism underlying these polymorphisms is critical to the validation process and, by identifying rate-limiting steps in AD risk, may yield novel therapeutic targets. Here, we elucidate the mechanism of action of the AD-associated polymorphism rs3865444 in the promoter of CD33, a member of the sialic acid-binding Ig-superfamily of lectins (SIGLECs). Immunostaining established that CD33 is expressed in microglia in human brain. Consistent with this finding, CD33 mRNA expression correlated well with expression of the microglial genes CD11b and AIF-1 and was modestly increased with AD status and the rs3865444C AD-risk allele. Analysis of CD33 isoforms identified a common isoform lacking exon 2 (D2-CD33). The proportion of CD33 expressed as D2-CD33 correlated robustly with rs3865444 genotype. Because rs3865444 is in the CD33 promoter region, we sought the functional polymorphism by sequencing CD33 from the promoter through exon 4. We identified a single polymorphism that is coinherited with rs3865444, i.e., rs12459419 in exon 2. Minigene RNA splicing studies in BV2 microglial cells established that rs12459419 is a functional single nucleotide polymorphism (SNP) that modulates exon 2 splicing efficiency. Thus, our primary findings are that CD33 is a microglial mRNA and that rs3865444 is a proxy SNP for rs12459419 that modulates CD33 exon 2 splicing. Exon 2 encodes the CD33 IgV domain that typically mediates sialic acid binding in SIGLEC family members. In summary, these results suggest a novel model wherein SNP-modulated RNA splicing modulates CD33 function and, thereby, AD risk.
To test for an association between the apolipoprotein E (APOE) ε4 allele and dementias with synucleinopathy.
Genetic case-control association study.
Autopsied subjects were classified into 5 categories: dementia with high-level Alzheimer disease (AD) neuropathologic changes (NCs) but without Lewy body disease (LBD) NCs (AD group; n=244), dementia with LBDNCs and high-level ADNCs (LBD-AD group; n=224), dementia with LBDNCs and no or low levels of ADNCs (pure DLB [pDLB] group; n=91), Parkinson disease dementia (PDD) with no or low levels of ADNCs (n=81), and control group (n=269).
Main Outcome Measure
The APOE allele frequencies.
The APOE ε4 allele frequency was significantly higher in the AD (38.1%), LBD-AD (40.6%), pDLB (31.9%), and PDD (19.1%) groups compared with the control group (7.2%; overall χ42=185.25; P=5.56×10−39), and it was higher in the pDLB group than the PDD group (P=.01). In an age-adjusted and sex-adjusted dominant model, ε4 was strongly associated with AD (odds ratio, 9.9; 95% CI, 6.4–15.3), LBD-AD (odds ratio, 12.6; 95% CI, 8.1–19.8), pDLB (odds ratio, 6.1; 95% CI, 3.5–10.5), and PDD (odds ratio, 3.1; 95% CI, 1.7–5.6).
The APOE ε4 allele is a strong risk factor across the LBD spectrum and occurs at an increased frequency in pDLB relative to PDD. This suggests that ε4 increases the likelihood of presenting with dementia in the context of a pure synucleinopathy. The elevated ε4 frequency in the pDLB and PDD groups, in which the overall brain neuritic plaque burden was low, indicates that apoE might contribute to neurodegeneration through mechanisms unrelated to amyloid processing.
Since the identification of TMPRSS2/ERG
rearrangement as the most common fusion event in prostate cancer, various
methods have been developed to detect this rearrangement and to study its
prognostic significance. We hereby report a novel 4-color fluorescence in
situ hybridization (FISH) assay that not only detects the typical
TMPRSS2:ERG fusion but also alternative rearrangements
of either the TMPRSS2 or ERG gene.
We validated this assay on fresh, frozen, or formalin-fixed
paraffin-embedded prostate cancer specimens including cell lines, primary
prostate cancer, xenograft tissues derived from metastatic prostate cancer,
and metastatic tissues from castration-resistant prostate cancer (CRPC)
When compared with RT-PCR or Gen-Probe method as the technical
reference, the 4-color FISH assay demonstrated an analytical sensitivity of
94.5% (95% Confidence Interval [CI] 0.80-0.99) and specificity of 100% (95%
CI 0.89-1.00) for detecting TMPRSS2:ERG fusion.
TMPRSS2:ERG fusion was detected at 41% and 43% in
primary prostate cancer (n = 59) and CRPC tumors (n = 82), respectively.
Alternative rearrangements other than the typical
TMPRSS2:ERG fusion were confirmed by karyotype analysis
and shown present in 7% primary cancer and 13% CRPC tumors. Successful
karyotype analysis is reported for the first time on four of the xenograft
samples, complementing the FISH results.
This 4-color FISH assay provides sensitive detection of
TMPRSS2 and ERG gene rearrangements in
Prostate cancer; TMPRSS2; ERG; FISH
Tissue microarrays provide unique resources for rapid evaluation and validation of tissue biomarkers. The Canary Foundation Retrospective Prostate Tissue Microarray Resource used a rigorous statistical design, quota sampling, a variation of the case-cohort study, to select patients for inclusion in a multicenter, retrospective prostate cancer tissue microarray cohort. The study is designed to definitively validate tissue biomarkers of prostate cancer recurrence after radical prostatectomy. Tissue samples from over 1,000 participants treated for prostate cancer with radical prostatectomy between 1995 and 2004 were selected at six participating institutions in the United States and Canada. This design captured the heterogeneity of screening and clinical practices in the contemporary North American population. Standardized clinical data were collected in a centralized database. The project has been informative in several respects. The scale and complexity of assembling tissue microarrays (TMAs) with over 200 cases at each of six sites involved unanticipated levels of effort and time. Our statistical design promises to provide a model for outcome-based studies where tissue localization methods are applied to high-density tissue microarrays.
Prostate Cancer; Prognosis; Tissue Microarray; quota sampling
MicroRNAs (miRNAs) are small (20–22 nucleotides) regulatory non-coding RNAs that strongly influence gene expression. Most prior studies addressing the role of miRNAs in neurodegenerative diseases (NDs) have focused on individual diseases such as Alzheimer’s disease (AD), making disease-to-disease comparisons impossible. Using RNA deep sequencing, we sought to analyze in detail the small RNAs (including miRNAs) in the temporal neocortex gray matter from non-demented controls (n = 2), AD (n = 5), dementia with Lewy bodies (n = 4), hippocampal sclerosis of aging (n = 4), and frontotemporal lobar dementia (FTLD) (n = 5) cases, together accounting for the most prevalent ND subtypes. All cases had short postmortem intervals, relatively high-quality RNA, and state-of-the-art neuropathological diagnoses. The resulting data (over 113 million reads in total, averaging 5.6 million reads per sample) and secondary expression analyses constitute an unprecedented look into the human cerebral cortical miRNome at single nucleotide resolution. While we find no apparent changes in isomiR or miRNA editing patterns in correlation with ND pathology, our results validate and extend previous miRNA profiling studies with regard to quantitative changes in NDs. In agreement with this idea, we provide independent cohort validation for changes in miR-132 expression levels in AD (n = 8) and FTLD (n = 14) cases when compared to controls (n = 8). The identification of common and ND-specific putative novel brain miRNAs and/or short-hairpin molecules is also presented. The challenge now is to better understand the impact of these and other alterations on neuronal gene expression networks and neuropathologies.
Alzheimer’s disease; deep sequencing; dementia with Lewy bodies; frontotemporal lobar dementia; hippocampal sclerosis; isomiR; microRNA; progressive supranuclear palsy
Annual influenza epidemics and occasional pandemics pose a severe threat to human health. Host cell factors required for viral spread but not for cellular survival are attractive targets for novel approaches to antiviral intervention. The cleavage activation of the influenza virus hemagglutinin (HA) by host cell proteases is essential for viral infectivity. However, it is unknown which proteases activate influenza viruses in mammals. Several candidates have been identified in cell culture studies, leading to the concept that influenza viruses can employ multiple enzymes to ensure their cleavage activation in the host. Here, we show that deletion of a single HA-activating protease gene, Tmprss2, in mice inhibits spread of mono-basic H1N1 influenza viruses, including the pandemic 2009 swine influenza virus. Lung pathology was strongly reduced and mutant mice were protected from weight loss, death and impairment of lung function. Also, after infection with mono-basic H3N2 influenza A virus body weight loss and survival was less severe in Tmprss2 mutant compared to wild type mice. As expected, Tmprss2-deficient mice were not protected from viral spread and pathology after infection with multi-basic H7N7 influenza A virus. In conclusion, these results identify TMPRSS2 as a host cell factor essential for viral spread and pathogenesis of mono-basic H1N1 and H3N2 influenza A viruses.
Seasonal influenza epidemics and pandemics represent a serious health threat to the human population. Resistance to presently available anti-viral drugs is frequently observed. Therefore, identification of new targets for anti-viral therapy is an urgent need. Host proteases are required for processing of the virus hemagglutinin and may thus represent a suitable target for intervention. Here, we report that the deletion of a single host protease gene, Tmprss2, in mice protects the host against viral spread in infected lungs. Only very mild pathogenesis was observed in Tmprss2 mutant mice after infection with H1N1 virus and less severe pathogenesis was observed after infection with H3N2 virus. Thus, our results suggest that the host protease TMPRSS2 may be a prime target for antiviral intervention.
The combination of expression patterns of AGR2 and CD10 by prostate cancer provided four phenotypes that correlated with clinical outcome. Based on immunophenotyping, CD10lowAGR2high, CD10highAGR2high, CD10lowAGR2low, and CD10highAGR2low were distinguished. AGR2+ tumors were associated with longer recurrence-free survival and CD10+ tumors with shorter recurrence-free survival. In high-stage cases, the CD10lowAGR2high phenotype was associated with a 9-fold higher recurrence-free survival than the CD10highAGR2low phenotype. The CD10highAGR2high and CD10lowAGR2low phenotypes were intermediate. The CD10highAGR2low phenotype was most frequent in high-grade primary tumors. Conversely, bone and other soft tissue metastases, and derivative xenografts, expressed more AGR2 and less CD10. AGR2 protein was readily detected in tumor metastases. The CD10highAGR2low phenotype in primary tumors is predictive of poor outcome; however, the CD10lowAGR2high phenotype is more common in metastases. It appears that AGR2 has a protective function in primary tumors but may have a role in the distal spread of tumor cells.
Prostate cancer; AGR2; CD10; cancer cell phenotypes; patient stratification; bone and soft tissue metastases; xenografts
Quantitative neuropathologic methods provide information that is important for both research and clinical applications. The technological advancement of digital pathology and image analysis offers new solutions to enable valid quantification of pathological severity that is reproducible between raters regardless of experience. Using an Aperio ScanScope XT and its accompanying image analysis software, we designed algorithms for quantitation of amyloid and tau pathologies on 65 β-amyloid (6F/3D antibody) and 48 phospho-tau (PHF-1)-immunostained sections of human temporal neocortex. Quantitative digital pathologic data were compared with manual pathology counts. There were excellent correlations between manually counted and digitally analyzed neuropathologic parameters (R2 values 0.56-0.72). Data were highly reproducible among 3 participants with varying degrees of expertise in neuropathology (Intra-class correlation coefficient values >0.910). Digital quantification also provided additional parameters, including average plaque area, which show statistically significant differences when samples are stratified according to APOE allele status (average plaque area 380.9 μm2 in ApoE ε4 carriers vs. 274.4 μm2 for non-carriers, p < 0.001). Thus, digital pathology offers a rigorous and reproducible method for quantifying AD neuropathologic changes and may provide additional insight into morphologic characteristics that were previously more challenging to assess due to technical limitations.
Alzheimer disease; Autopsy; Digital pathology; Image analysis; Neuropathology
Active surveillance is a management plan for localized prostate cancer that offers selective delayed intervention upon indication of disease progression, allowing patients to delay or avoid treatment and associated side-effects. Outcomes from centers that promote active surveillance are favorable, with high rates of disease-specific survival. However, there remains a need for prognostic variables or biomarkers that distinguish with high specificity the aggressive cancers that progress on surveillance from the indolent cancers. The Canary Prostate Active Surveillance Study(PASS) is a multicenter study and biorepository that will discover and confirm biomarkers of aggressive disease as defined by histologic, PSA, or clinical criteria.
Prostate cancer; Active Surveillance; Clinical Trial
Mutations in the GBA gene occur in 7% of patients with Parkinson disease (PD) and are a well-established susceptibility factor for PD, which is characterized by Lewy body disease (LBD) neuropathologic changes (LBDNCs). We sought to determine whether GBA influences risk of dementia with LBDNCs, Alzheimer disease (AD) neuropathologic changes (ADNCs), or both.
We screened the entire GBA coding region for mutations in controls and in subjects with dementia and LBDNCs and no or low levels of ADNCs (pure dementia with Lewy bodies [pDLB]), LBDNCs and high-level ADNCs (LBD-AD), and high-level ADNCs but without LBDNCs (AD).
Among white subjects, pathogenic GBA mutations were identified in 6 of 79 pDLB cases (7.6%), 8 of 222 LBD-AD cases (3.6%), 2 of 243 AD cases (0.8%), and 3 of 381 controls (0.8%). Subjects with pDLB and LBD-AD were more likely to carry mutations than controls (pDLB: odds ratio [OR] = 7.6; 95% confidence interval [CI] = 1.8–31.9; p = 0.006; LBD-AD: OR = 4.6; CI = 1.2–17.6; p = 0.025), but there was no significant difference in frequencies between the AD and control groups (OR = 1.1; CI = 0.2–6.6; p = 0.92). There was a highly significant trend test across groups (χ2(1) = 19.3; p = 1.1 × 10−5), with the likelihood of carrying a GBA mutation increasing in the following direction: control/AD < LBD-AD < pDLB.
GBA is a susceptibility gene across the LBD spectrum, but not in AD, and appears to convey a higher risk for PD and pDLB than for LBD-AD. PD and pDLB might be more similar to one another in genetic determinants and pathophysiology than either disease is to LBD-AD.
Amine catabolism by Monoamine Oxidase A (MAOA) contributes to oxidative stress, which plays a role in prostate cancer (PCa) development and progression. An upstream variable-number tandem repeat (uVNTR) in the MAOA promoter influences gene expression and activity, and may thereby affect PCa susceptibility.
Caucasian (n=2,572) men from two population-based case-control studies of PCa were genotyped for the MAOA-VNTR. Logistic regression was used to assess PCa risk in relation to genotype.
Common alleles of the MAOA-VNTR were not associated with the relative risk of PCa, nor did the relationship differ by clinical features of the disease. The rare 5-copy variant (frequency: 0.5% in cases; 1.8% in controls), however, was associated with a reduced PCa risk (odds ratio, OR=0.30, 95% CI 0.13–0.71).
A rare polymorphism of the MAOA promoter previously shown to confer low expression was associated with a reduced risk of developing prostate cancer. This novel finding awaits confirmation in other study populations.
MAOA; polymorphism; prostate cancer
Tangle-predominant dementia (TPD) patients exhibit cognitive decline that is clinically similar to early to moderate-stage Alzheimer disease (AD), yet autopsy reveals neurofibrillary tangles in the medial temporal lobe composed of the microtubule-associated protein tau without significant amyloid-beta (Aβ)-positive plaques. We performed a series of neuropathological, biochemical and genetic studies using autopsy brain tissue drawn from a cohort of 34 TPD, 50 AD and 56 control subjects to identify molecular and genetic signatures of this entity. Biochemical analysis demonstrates a similar tau protein isoform composition in TPD and AD, which is compatible with previous histological and ultrastructural studies. Further, biochemical analysis fails to uncover elevation of soluble Aβ in TPD frontal cortex and hippocampus compared to control subjects, demonstrating that non-plaque-associated Aβ is not a contributing factor. Unexpectedly, we also observed high levels of secretory amyloid precursor protein α (sAPPα) in the frontal cortex of some TPD patients compared to AD and control subjects, suggesting differences in APP processing. Finally, we tested whether TPD is associated with changes in the tau gene (MAPT). Haplotype analysis demonstrates a strong association between TPD and the MAPT H1 haplotype, a genomic inversion associated with some tauopathies and Parkinson disease (PD), when compared to age-matched control subjects with mild degenerative changes, i.e., successful cerebral aging. Next-generation resequencing of MAPT followed by association analysis shows an association between TPD and two polymorphisms in the MAPT 3′ untranslated region (UTR). These results support the hypothesis that haplotype-specific variation in the MAPT 3′ UTR underlies an Aβ-independent mechanism for neurodegeneration in TPD.
Dementia; Neurofibrillary tangle; Tau; Amyloid; MAPT; 3′ Untranslated region; Aging; Alzheimer’s disease; sAPPα
A decrease in glomerular podocyte number in membranous nephropathy and FSGS ultimately precipitates glomerulosclerosis and the decrease in kidney function. Recent studies have shown that in these diseases, glomerular parietal epithelial cells begin to express proteins considered unique to podocytes, and that these glomerular epithelial transition cells might serve as podocyte progenitors. Because retinoids improve many forms of experimental glomerular disease characterized by podocyte injury and loss, we asked if ATRA induces parietal epithelial cells to express podocyte proteins.
ATRA or vehicle was administered to rats with experimental membranous nephropathy (PHN model) and mice with experimental FSGS (anti-glomerular antibody model) following the onset of proteinuria. Immunohistochemistry staining of PAX2 (parietal epithelial cell marker), WT-1 (podocyte cell marker), and Ki-67 (proliferation marker) were performed on kidney tissues.
Compared to diseased animals receiving vehicle, ATRA statistically significantly increased the number of glomerular transition cells, defined as cells double staining for PAX2 and WT-1, in membranous nephropathy at weeks 2, 5 and 16, and in FSGS at weeks 1 and 2. This was accompanied by an increase in the number of podocytes compared to diseased controls receiving vehicle.
ATRA increases the number of glomerular epithelial transition cells in experimental proteinuric glomerular diseases. Thus, ATRA may provide a useful pharmacologic approach to decipher the mechanisms underlying the possible progenitor role of parietal epithelial cells.
all-trans retinoic acid; proteinuria; passive Heymann nephritis; membranous nephropathy; focal segmental glomerulosclerosis
Adoptive or active cancer immunotherapy can fail owing to the inefficient recruitment of effector leukocytes to malignant lesions. The intratumoral injection of recombinant proteins comprising a chemokine-derived domain linked to the mucin stalk of chemokine (C-X3-C motif) ligand 1 (CX3CL1) and a glycosylphosphatidylinositol anchor can specifically enhance the recruitment of effector cell subsets to solid tumors.
active immunotherapy; adoptive immunotherapy; cancer therapy; chemokine; endothelial anergy; GPI anchor; leukocyte recruitment
The Nephrotic Syndrome Study Network (NEPTUNE) is a North American multi-center collaborative consortium established to develop a translational research infrastructure for Nephrotic Syndrome. This includes a longitudinal observational cohort study, a pilot and ancillary studies program, a training program, and a patient contact registry. NEPTUNE will enroll 450 adults and children with minimal change disease, focal segmental glomerulosclerosis and membranous nephropathy for detailed clinical, histopathologic, and molecular phenotyping at the time of clinically-indicated renal biopsy. Initial visits will include an extensive clinical history, physical examination, collection of urine, blood and renal tissue samples, and assessments of quality of life and patient-reported outcomes. Follow-up history, physical measures, urine and blood samples, and questionnaires will be obtained every 4 months in the first year and bi-annually, thereafter. Molecular profiles and gene expression data will be linked to phenotypic, genetic, and digitalized histologic data for comprehensive analyses using systems biology approaches. Analytical strategies were designed to transform descriptive information to mechanistic disease classification for Nephrotic Syndrome and to identify clinical, histological, and genomic disease predictors. Thus, understanding the complexity of the disease pathogenesis will guide further investigation for targeted therapeutic strategies.
TMPRSS2/ERG rearrangement, PTEN gene deletion, and androgen receptor (AR) gene amplification have been observed in various stages of human prostate cancer. We hypothesized that using these markers as a combined panel would allow better differentiation between low-risk and high-risk prostate cancer. We analyzed 110 primary prostate cancer samples, 70 metastatic tumor samples from 11 patients, and 27 xenograft tissues derived from 22 advanced prostate cancer patients using fluorescence in situ hybridization (FISH) analysis with probes targeting the TMPRSS2/ERG, PTEN, and AR gene loci. Heterogeneity of the aberrations detected was evaluated. Genetic patterns were also correlated with transcript levels. Among samples with complete data available, the three-marker FISH panel detected chromosomal abnormalities in 53% of primary prostate cancers and 87% of metastatic (Met) or castration-resistant (CRPC) tumors. The number of markers with abnormal FISH result had a different distribution between the two groups (P<0.001). At the patient level, Met/CRPC tumors are 4.5 times more likely to show abnormalities than primary cancer patients (P<0.05). Heterogeneity among Met/CRPC tumors is mostly inter-patient. Intra-patient heterogeneity is primarily due to differences between the primary prostate tumor and the metastases while multiple metastatic sites show consistent abnormalities. Intra-tumor variability is most prominent with the AR copy number in primary tumors. AR copy number correlated well with the AR mRNA expression (rho = 0.52, P<0.001). Especially among TMPRSS2:ERG fusion-positive CRPC tumors, AR mRNA and ERG mRNA levels are strongly correlated (rho = 0.64, P<0.001). Overall, the three-marker FISH panel may represent a useful tool for risk stratification of prostate cancer patients.
Simultaneous treatment of multilevel aortic disease is controversial due to the theoretic increase in morbidity. This study was conducted to define the outcomes in patients treated electively with simultaneous thoracic endovascular aortic aneurysm repair (TEVAR) and abdominal aortic endovascular endografting for synchronous aortic pathology.
Patients treated with simultaneous TEVAR and endovascular aneurysm repair (T&E) at the University of Florida were identified from a prospectively maintained endovascular aortic registry and compared with those treated with TEVAR alone (TA). The study excluded patients with urgent or emergency indications, thoracoabdominal or mycotic aneurysm, and those requiring chimney stents, fenestrations, or visceral debranching procedures. Demographics, anatomic characteristics, operative details, and periprocedural morbidity were recorded. Mortality and reintervention were estimated using life-table analysis.
From 2001 to 2011, 595 patients underwent TEVAR, of whom 457 had elective repair. Twenty-two (18 men, 82%) were identified who were treated electively with simultaneous T&E. Mean ± standard deviation age was 66 ± 9 years, and median follow-up was 8.8 months (range, 1–34 months). Operative indications for the procedure included dissection-related pathology in 10 (45%) and various combinations of degenerative etiologies in 12 (55%). Compared with TA, T&E patients had significantly higher blood loss (P < .0001), contrast exposure (P < .0001), fluoroscopy time (P < .0001), and operative time (P < .0001). The temporary spinal cord ischemia rate was 13.6% (n = 3) for the T&E group and 6.0% for TA (P = .15); however, the permanent spinal cord ischemia rate was 4% for both groups (P = .96). The 30-day mortality for T&E was 4.5% (n = 1) compared with 2.1% (n = 10) for TA. Temporary renal injury (defined by a 25% increase over baseline creatinine) occurred in two T&E patients (9.1%), with none requiring permanent hemodialysis; no significant difference was noted between the two groups (P = .14). One-year mortality and freedom from reintervention in the T&E patients were 81% and 91%, respectively.
Acceptable short-term morbidity and mortality can be achieved with T&E compared with TA, despite longer operative times, greater blood loss, and higher contrast exposure. There was a trend toward higher rates of renal and spinal cord injury, so implementation of strategies to reduce the potential of these complications or consideration of staged repair is recommended. Short-term reintervention rates are low, but longer follow-up and greater patient numbers are needed to determine procedural durability and applicability.
Androgen deprivation therapy remains the primary treatment modality for patients with metastatic prostate cancer but is uniformly marked by progression to castration-resistant prostate cancer (CRPC) after a period of regression. Continued activation of androgen receptor (AR) signaling is attributed as one of the most important mechanisms underlying failure of therapy. Recently, the discovery of constitutively active AR splice variants (AR-Vs) adds more credence to this idea. Expression of AR-Vs in metastases portends a rapid progression of the tumor. However, the precise role of the AR-Vs in CRPC still remains unknown. ARv567es is one of the two AR variants frequently found in human CRPC xenografts and metastases. Herein, we developed a probasin (Pb) promoter-driven ARv567es transgenic mouse, Pb-ARv567es, to evaluate the role of ARv567es in both autonomous prostate growth and progression to CRPC. We found that expression of ARv567es in the prostate results in epithelial hyperplasia by 16 weeks and invasive adenocarcinoma is evident by 1 year of age. The underlying genetic cellular events involved a cell cycle-related transcriptome and differential expression of a spectrum of genes that are critical for tumor initiation and progression. These findings indicate that ARv567es could induce tumorigenesis de novo and signifies the critical role of AR-Vs in CRPC. Thus, the Pb-ARv567es mouse could provide a novel model in which the role of AR variants in prostate cancer progression can be examined.
Cellular therapy is a promising therapeutic strategy for malignant diseases. The efficacy of this therapy can be limited by poor infiltration of the tumor by immune effector cells. In particular, NK cell infiltration is often reduced relative to T cells. A novel class of fusion proteins was designed to enhance the recruitment of specific leukocyte subsets based on their expression of a given chemokine receptor. The proteins are composed of an N-terminal chemokine head, the mucin domain taken from the membrane-anchored chemokine CX3CL1, and a C-terminal glycosylphosphatidylinositol (GPI) membrane anchor replacing the normal transmembrane domain allowing integration of the proteins into cell membranes when injected into a solid tumor. The mucin domain in conjunction with the chemokine head acts to specifically recruit leukocytes expressing the corresponding chemokine receptor.
A fusion protein comprising a CXCL10 chemokine head (CXCL10-mucin-GPI) was used for proof of concept for this approach and expressed constitutively in Chinese Hamster Ovary cells. FPLC was used to purify proteins. The recombinant proteins efficiently integrated into cell membranes in a process dependent upon the GPI anchor and were able to activate the CXCR3 receptor on lymphocytes. Endothelial cells incubated with CXCL10-mucin-GPI efficiently recruited NK cells in vitro under conditions of physiologic flow, which was shown to be dependent on the presence of the mucin domain. Experiments conducted in vivo using established tumors in mice suggested a positive effect of CXCL10-mucin-GPI on the recruitment of NK cells.
The results suggest enhanced recruitment of NK cells by CXCL10-mucin-GPI. This class of fusion proteins represents a novel adjuvant in cellular immunotherapy. The underlying concept of a chemokine head fused to the mucin domain and a GPI anchor signal sequence may be expanded into a broader family of reagents that will allow targeted recruitment of cells in various settings.
The armamentarium of therapeutics used to treat cancer patients relies heavily on ionizing radiation and chemotherapeutic drugs that severely damage DNA. The responses of tumor cells to these treatments is heavily influenced by their environment: physical contacts with structural elements such as extracellular matrix, associations with resident and transitory benign cells such as fibroblasts and leukocytes, and interactions with numerous soluble endocrine and paracrine-acting factors all modulate tumor cell behavior. Importantly, this complex tumor microenvironment is not static and dynamically responds to a variety of stimuli. Here, we describe emerging data indicating that genotoxic cancer treatments activate highly conserved damage response programs in benign constituents of the tumor microenvironment. These damage signals, transmitted via master regulators such as NFkB, culminate in a powerful and diverse secretory program that generates a pro-angiogenic, pro-inflammatory microenvironment. Constituents of this program include Interleukin (IL)-6, IL-8, hepatocyte growth factor, amphiregulin, matrix metalloproteinases, and other factors demonstrated to promote adverse tumor cell phenotypes including enhanced resistance to treatment and rapid tumor repopulation. A detailed understanding of these survival signals induced in the context of genotoxic stress provides a platform to develop combinatorial strategies to improve outcomes that consider malignant cells, the tumor microenvironment, and the dynamics exerted by the treatment itself.
DNA damage response; therapy resistance; senescence; paracrine; stroma
MicroRNAs (miRNAs) are small (∼22 nucleotide) non-coding RNAs that regulate a myriad of biological processes and are frequently dysregulated in cancer. Cancer-associated microRNAs have been detected in serum and plasma and hold promise as minimally invasive cancer biomarkers, potentially for assessing disease characteristics in patients with metastatic disease that is difficult to biopsy. Here we used miRNA profiling to identify cancer-associated miRNAs that are differentially expressed in sera from patients with metastatic castration resistant prostate cancer (mCRPC) as compared to healthy controls. Of 365 miRNAs profiled, we identified five serum miRNAs (miR-141, miR-200a, miR-200c, miR-210 and miR-375) that were elevated in cases compared to controls across two independent cohorts. One of these, miR-210, is a known transcriptional target of the hypoxia-responsive HIF-1α signaling pathway. Exposure of cultured prostate cancer cells to hypoxia led to induction of miR-210 and its release into the extracellular environment. Moreover, we found that serum miR-210 levels varied widely amongst mCRPC patients undergoing therapy, and correlated with treatment response as assessed by change in PSA. Our results suggest that (i) cancer-associated hypoxia is a frequent, previously under-appreciated characteristic of mCRPC, and (ii) serum miR-210 may be further developed as a predictive biomarker in patients with this distinct disease biology.
Continued androgen receptor (AR) signaling is an established mechanism underlying castration-resistant prostate cancer (CRPC), and suppression of AR signaling remains a therapeutic goal of CRPC therapy. Constitutively active androgen receptor splice variants (AR-Vs) lack the AR ligand-binding domain (AR-LBD), the intended target of androgen deprivation therapies (ADT) including CRPC therapies such as abiraterone and MDV3100. While the canonical full-length AR (AR-FL) and AR-Vs are both increased in CRPC, their expression regulation, associated transcriptional programs, and functional relationships have not been dissected. In this study, we show that suppression of ligand-mediated AR-FL signaling by targeting AR-LBD leads to increased AR-V expression in two cell line models of CRPC. Importantly, treatment-induced AR-Vs activated a distinct expression signature enriched for cell cycle genes without requiring the presence of AR-FL. Conversely, activation of AR-FL signaling suppressed the AR-V signature and activated expression programs mainly associated with macromolecular synthesis, metabolism, and differentiation. In prostate cancer cells and CRPC xenografts treated with MDV3100 or abiraterone, increased expression of two constitutively active AR-Vs, AR-V7 and ARV567ES, but not AR-FL, paralleled increased expression of the AR-driven cell cycle gene UBE2C. Expression of AR-V7, but not AR-FL, was positively correlated with UBE2C in clinical CRPC specimens. Together, our findings support an adaptive shift toward AR-V-mediated signaling in a subset of CRPC tumors as the AR-LBD is rendered inactive, suggesting an important mechanism contributing to drug resistance to CRPC therapy.
androgen receptor; castration-resistant prostate cancer; androgen receptor splice variants; MDV3100; abiraterone
Risk factors for mild cognitive impairment (MCI) and dementia are often investigated without accounting for the competing risk of mortality, which can bias results and lead to spurious conclusions, particularly regarding protective factors. Here, we apply a semi-Markov modeling approach to 531 participants in the University of Kentucky Biologically Resilient Adults in Neurological Studies (BRAiNS) longitudinal cohort, over one-third of whom died without transitioning to a cognitively impaired clinical state. A semi-Markov approach enables a statistical study of clinical state transitions while accounting for the competing risk of death and facilitates insights into both the odds that a risk factor will affect clinical transitions as well as the age at which the transition to MCI or dementia will occur. Risk factors assessed in the current study were identified by matching those reported in the literature with the data elements collected on participants. The presence of Type II diabetes at baseline shortens the time it takes cognitively intact individuals to transition to MCI by seven years on average while use of estrogen replacement therapy at enrollment (baseline) decreases the time required to convert from MCI to dementia by 1.5 years. Finally, smoking and being overweight do not promote transitions to impaired states but instead hasten death without a dementia. In contrast, conventional statistical analyses based on Cox proportional hazards models fail to recognize diabetes as a risk and show that being overweight increases the risk of clinical MCI while high blood pressure at baseline increases the risk of a dementia.
MCI; dementia; multi-state models; semi-Markov; risk factors; competing events
Acquired resistance to anticancer treatments is a substantial barrier to reducing the morbidity and mortality that is attributable to malignant tumors. Components of tissue microenvironments are recognized to profoundly influence cellular phenotypes, including susceptibilities to toxic insults. Using a genome-wide analysis of transcriptional responses to genotoxic stress induced by cancer therapeutics, we identified a spectrum of secreted proteins derived from the tumor microenvironment that includes the Wnt family member wingless-type MMTV integration site family member 16B (WNT16B). We determined that WNT16B expression is regulated by nuclear factor of κ light polypeptide gene enhancer in B cells 1 (NF-κB) after DNA damage and subsequently signals in a paracrine manner to activate the canonical Wnt program in tumor cells. The expression of WNT16B in the prostate tumor microenvironment attenuated the effects of cytotoxic chemotherapy in vivo, promoting tumor cell survival and disease progression. These results delineate a mechanism by which genotoxic therapies given in a cyclical manner can enhance subsequent treatment resistance through cell nonautonomous effects that are contributed by the tumor microenvironment.
Oxidative stress is involved in age-related cognitive decline. The dietary antioxidants, carotenoids, tocopherols, and vitamin A may play a role in the prevention or delay in cognitive decline. In this study, sera were obtained from 78 octogenarians and 220 centenarians from the Georgia Centenarian Study. Brain tissues were obtained from 47 centenarian decedents. Samples were analyzed for carotenoids, α-tocopherol, and retinol using HPLC. Analyte concentrations were compared with cognitive tests designed to evaluate global cognition, dementia, depression and cognitive domains (memory, processing speed, attention, and executive functioning). Serum lutein, zeaxanthin, and β-carotene concentrations were most consistently related to better cognition (P < 0.05) in the whole population and in the centenarians. Only serum lutein was significantly related to better cognition in the octogenarians. In brain, lutein and β-carotene were related to cognition with lutein being consistently associated with a range of measures. There were fewer significant relationships for α-tocopherol and a negative relationship between brain retinol concentrations and delayed recognition. These findings suggest that the status of certain carotenoids in the old may reflect their cognitive function. The protective effect may not be related to an antioxidant effect given that α-tocopherol was less related to cognition than these carotenoids.