Prevalence and Spectrum of AR Ligand-Binding Domain Mutations Detected in Circulating-Tumor DNA Across Disease States in Men With Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: Metastatic castration-resistant prostate cancer (mCRPC) is typically treated with agents directly or indirectly targeting the androgen receptor (AR) pathway. However, such treatment is limited by resistance mechanisms, including the development of activating mutations in the AR ligand-binding domain (AR-LBD). METHODS: This study evaluated a database of over 15,000 patients with advanced prostate cancer (PC) undergoing comprehensive circulating-tumor DNA analysis (Guardant360, Redwood City, CA) between 2014 and 2021, with associated clinical information from administrative claims (GuardantINFORM database). RESULTS: Of 15,705 patients with PC included, 54% had mCRPC at the time of their blood draw. Of those, 49% had previous treatment with an AR pathway inhibitor (ARPi). AR-LBD mutation prevalence was 15% in patients with mCRPC who were untreated with a next-generation ARPi, 22% in those after one line of ARPi therapy, and 24% in those after two lines of ARPi treatment. Next-generation ARPi treatment yielded an increase in AR L702H and T878A/S mutations after abiraterone, and an increase in AR L702H and F877L mutations after enzalutamide. AR-LBD+ patients demonstrated unique biology, including increased concurrent mutations in the cell-cycle, wingless-related integration site, homologous recombination repair, and phospho-inositide 3-kinase pathways (all P < .0005), and greater low-level (copy number <10) AR amplifications (P = .0041). AR-LBD+ patients exhibited worse overall survival (OS) relative to a matched cohort of AR-LBD- patients (50.1 v 60.7 months, unadjusted log-rank P = .013). CONCLUSION: This large database analysis demonstrates that AR-LBD mutation prevalence increases after next-generation ARPi use. AR-LBD+ tumors demonstrate unique biology (more oncogenic pathway mutations and low-level AR amplification) and reduced OS. These findings inform the development of novel therapies designed to circumvent AR-mediated therapeutic resistance.

Comparing Prevalence of Sarcopenia Using Twelve Sarcopenia Definitions in a Large Multinational European Population of Community-Dwelling Older Adults.

OBJECTIVES: Multinational prevalence data on sarcopenia among generally healthy older adults is limited. The aim of the study was to assess prevalence of sarcopenia in the DO-HEALTH European trial based on twelve current sarcopenia definitions. SETTING AND PARTICIPANTS: This is an analysis of the DO-HEALTH study including 1495 of 2157 community-dwelling participants age 70+ years from Germany, France, Portugal, and Switzerland with complete measurements of the sarcopenia toolbox including muscle mass by DXA, grip strength, and gait speed. MEASUREMENTS: The twelve sarcopenia definitions applied were Asian Working Group on Sarcopenia (AWGS1), AWGS2, Baumgartner, Delmonico, European Working Group on Sarcopenia in Older People (EWGSOP1), EWGSOP2, EWGSOP2-lower extremities, Foundation for the National Institutes of Health (FNIH1), FNIH2, International Working Group on Sarcopenia in Older People (IWGS), Morley, and Sarcopenia Definitions and Outcomes Consortium (SDOC). RESULTS: Mean age was 74.9 years (SD 4.4); 63.3% were women. Sarcopenia prevalence ranged between 0.7% using the EWGSOP2 or AWGS2 definition, up to 16.8% using the Delmonico definition. Overall, most sarcopenia definitions, including Delmonico (16.8%), Baumgartner (12.8%), FNIH1(10.5%), IWGS (3.6%), EWGSOP1 (3.4%), SDOC (2.0%), Morley (1.3%), and AWGS1 (1.1%) tended to be higher than the prevalence based on EWGSOP2 (0.7%). In contrast, the definitions AWGS2 (0.7%), EWGSOP2-LE (1.1%), FNIH2 (1.0%) - all based on muscle mass and muscle strength - showed similar lower prevalence as EWGSOP2 (0.7%). Moreover, most sarcopenia definitions did not overlap on identifying sarcopenia on an individual participant-level. CONCLUSION: In this multinational European trial of community-dwelling older adults we found major discordances of sarcopenia prevalence both on a population- and on a participant- level between various sarcopenia definitions. Our findings suggest that the concept of sarcopenia may need to be rethought to reliably and validly identify people with impaired muscle health.

Contrary response of porcine articular cartilage below and over 1000 s-1.

BACKGROUND: Knee joints experience excessive loads quite frequently during sports activities, and these shocks could accelerate progressive degeneration in articular cartilage. METHODS: Quasi-static and dynamic response of porcine knee articular cartilages were investigated in this research. Split Hopkinson Pressure Bars (SHPB) were utilized to examine the articular cartilage properties at strain rates between 0.01-2000 s-1. FINDINGS: The results showed that strain rate is an important factor for articular cartilages, distinctively divided into above and below 1000 s-1. The articular cartilages exhibit a strain hardening phenomenon when shock loaded at strain rates under 1000 s-1. When loaded at strain rates over 1000 s-1, their ultimate strength and elastic modulus decreased with increasing strain rates. INTERPRETATION: The biphasic structure of the cartilage explained the change of modulus. At the lower strain rates, fibers realigned and solidified the structure, while at higher strain rates, there is not enough time for the tissue fluid to move inside the cartilage, leading to a reduction in the deformability of the specimen and raising of Young's modulus. The results can be utilized to provide some useful data for biomaterial and computational works in the future.

Induction of specific brain oscillations may restore neural circuits and be used for the treatment of Alzheimer's disease.

Brain oscillations underlie the function of our brains, dictating how we both think and react to the world around us. The synchronous activity of neurons generates these rhythms, which allow different parts of the brain to communicate and orchestrate responses to internal and external stimuli. Perturbations of cognitive rhythms and the underlying oscillator neurons that synchronize different parts of the brain contribute to the pathophysiology of diseases including Alzheimer's disease, (AD), Parkinson's disease (PD), epilepsy and other diseases of rhythm that have been studied extensively by Gyorgy Buzsaki. In this review, we discuss how neurologists manipulate brain oscillations with neuromodulation to treat diseases and how this can be leveraged to improve cognition and pathology underlying AD. While multiple modalities of neuromodulation are currently clinically indicated for some disorders, nothing is yet approved for improving memory in AD. Recent investigations into novel methods of neuromodulation show potential for improving cognition in memory disorders. Here, we demonstrate that neuronal stimulation using audiovisual sensory stimulation that generated 40-HZ gamma waves reduced AD-specific pathology and improved performance in behavioural tests in mouse models of AD, making this new mode of neuromodulation a promising new avenue for developing a new therapeutic intervention for the treatment of dementia.

BLM has Contrary Effects on Repeat-Mediated Deletions, based on the Distance of DNA DSBs to a Repeat and Repeat Divergence.

Repeat-mediated deletions (RMDs) often involve repetitive elements (e.g., short interspersed elements) with sequence divergence that is separated by several kilobase pairs (kbps). We have examined RMDs induced by DNA double-strand breaks (DSBs) under varying conditions of repeat sequence divergence (identical versus 1% and 3% divergent) and DSB/repeat distance (16 bp-28.4 kbp). We find that the BLM helicase promotes RMDs with long DSB/repeat distances (e.g., 28.4 kbp), which is consistent with a role in extensive DSB end resection, because the resection nucleases EXO1 and DNA2 affect RMDs similarly to BLM. In contrast, BLM suppresses RMDs with sequence divergence and intermediate (e.g., 3.3 kbp) DSB/repeat distances, which supports a role in heteroduplex rejection. The role of BLM in heteroduplex rejection is not epistatic with MSH2 and is independent of the annealing factor RAD52. Accordingly, the role of BLM on RMDs is substantially affected by DSB/repeat distance and repeat sequence divergence.

The canonical non-homologous end joining factor XLF promotes chromosomal deletion rearrangements in human cells.

Clastogen exposure can result in chromosomal rearrangements, including large deletions and inversions that are associated with cancer development. To examine such rearrangements in human cells, here we developed a reporter assay based on endogenous genes on chromosome 12. Using the RNA-guided nuclease Cas9, we induced two DNA double-strand breaks, one each in the GAPDH and CD4 genes, that caused a deletion rearrangement leading to CD4 expression from the GAPDH promoter. We observed that this GAPDH-CD4 deletion rearrangement activates CD4+ cells that can be readily detected by flow cytometry. Similarly, double-strand breaks in the LPCAT3 and CD4 genes induced an LPCAT3-CD4 inversion rearrangement resulting in CD4 expression. Studying the GAPDH-CD4 deletion rearrangement in multiple cell lines, we found that the canonical non-homologous end joining (C-NHEJ) factor XLF promotes these rearrangements. Junction analysis uncovered that the relative contribution of C-NHEJ appears lower in U2OS than in HEK293 and A549 cells. Furthermore, an ATM kinase inhibitor increased C-NHEJ-mediated rearrangements only in U2OS cells. We also found that an XLF residue that is critical for an interaction with the C-NHEJ factor X-ray repair cross-complementing 4 (XRCC4), and XRCC4 itself are each important for promoting both this deletion rearrangement and end joining without insertion/deletion mutations. In summary, a reporter assay based on endogenous genes on chromosome 12 reveals that XLF-dependent C-NHEJ promotes deletion rearrangements in human cells and that cell type-specific differences in the contribution of C-NHEJ and ATM kinase inhibition influence these rearrangements.

Effects of treadmill running and limb immobilization on knee cartilage degeneration and locomotor joint kinematics in rats following knee meniscal transection.

OBJECTIVE: This study examined the effects of reduced and elevated weight bearing on post-traumatic osteoarthritis (PTOA) development, locomotor joint kinematics, and degree of voluntary activity in rats following medial meniscal transection (MMT). DESIGN: Twenty-one adult rats were subjected to MMT surgery of the left hindlimb and then assigned to one of three groups: (1) regular (i.e., no intervention), (2) hindlimb immobilization, or (3) treadmill running. Sham surgery was performed in four additional rats. Voluntary wheel run time/distance was measured, and 3D hindlimb kinematics were quantified during treadmill locomotion using biplanar radiography. Rats were euthanized 8 weeks after MMT or sham surgery, and the microstructure of the tibial cartilage and subchondral bone was quantified using contrast enhanced micro-CT. RESULTS: All three MMT groups showed signs of PTOA (full-thickness lesions and/or increased cartilage volume) compared to the sham group, however the regular and treadmill-running groups had greater osteophyte formation than the immobilization group. For the immobilization group, increased volume was only observed in the anterior region of the cartilage. The treadmill-running group demonstrated a greater knee varus angle at mid-stance than the sham group, while the immobilization group demonstrated greater reduction in voluntary running than all the other groups at 2 weeks post-surgery. CONCLUSIONS: Elevated weight-bearing via treadmill running at a slow/moderate speed did not accelerate PTOA in MMT rats when compared to regular weight-bearing. Reduced weight-bearing via immobilization may attenuate overall PTOA but still resulted in regional cartilage degeneration. Overall, there were minimal differences in hindlimb kinematics and voluntary running between MMT and sham rats.

MUC1 inhibition leads to decrease in PD-L1 levels via upregulation of miRNAs.

The PD-L1/PD-1 pathway is a critical component of the immunosuppressive tumor microenvironment in acute myeloid leukemia (AML), but little is known about its regulation. We investigated the role of the MUC1 oncoprotein in modulating PD-L1 expression in AML. Silencing of MUC1 in AML cell lines suppressed PD-L1 expression without a decrease in PD-L1 mRNA levels, suggesting a post-transcriptional mechanism of regulation. We identified the microRNAs miR-200c and miR-34a as key regulators of PD-L1 expression in AML. Silencing of MUC1 in AML cells led to a marked increase in miR-200c and miR-34a levels, without changes in precursor microRNA, suggesting that MUC1 might regulate microRNA-processing. MUC1 signaling decreased the expression of the microRNA-processing protein DICER, via the suppression of c-Jun activity. NanoString (Seattle, WA, USA) array of MUC1-silenced AML cells demonstrated an increase in the majority of probed microRNAs. In an immunocompetent murine AML model, targeting of MUC1 led to a significant increase in leukemia-specific T cells. In concert, targeting MUC1 signaling in human AML cells resulted in enhanced sensitivity to T-cell-mediated lysis. These findings suggest MUC1 is a critical regulator of PD-L1 expression via its effects on microRNA levels and represents a potential therapeutic target to enhance anti-tumor immunity.

A 15-year-long Southern blotting analysis of FMR1 to detect female carriers and for prenatal diagnosis of fragile X syndrome in Taiwan.

Here, we review the results of Southern blotting analyses of the FMR1 gene performed in our reference laboratory in Taiwan over a 15-year period. In total, 725 high-risk women with a family history of fragile X syndrome (FXS) or idiopathic intellectual disability, 3911 low-risk pregnant women without such family history, and prenatal diagnosis data for 32 foetuses from 24 carrier mothers were included. Only 2 carriers were in the low-risk group, which indicated a prevalence of 1 of 1955 women (95% confidence interval: 1/7156-1/539). A total of 100 carriers were found to be in the high-risk group, thus revealing a significantly higher frequency than the low-risk group (100/725 vs 2/3911, P<0.0001). Eight of the 14 foetuses that inherited the maternal mutant allele were verified to have a full mutation, with the smallest maternal pre-mutation allele carrying 56 CGG repeats. The overall findings confirmed that the carrier prevalence among low-risk women in Taiwan is significantly lower than that reported in western countries. Therefore, the most important step for preventing FXS in Taiwan would be to focus on high-risk women by promoting general awareness of this disease and spreading knowledge regarding the benefits of carrier screening and prenatal testing.

Proximal humeral fractures in Sweden-a registry-based study.

Proximal humeral fracture is the third most common osteoporotic fracture. To our knowledge, this is the first nationwide population-based registry study in adults that includes both inpatient and outpatient visits. Thus, we were able to report the true incidence rates and trends in the treatment of proximal humeral fractures. INTRODUCTION: Proximal humeral fractures are among the most common osteoporotic fractures. Valid epidemiologic population-based data, including both inpatient and outpatient visits, however, are lacking. METHODS: To investigate the Swedish national incidence rates and treatment trends of proximal humeral fractures, we obtained data from the Swedish Hospital Discharge Register between 2001 and 2012. All adult patients (≥18 years of age) in the Swedish Hospital Discharge Register were included. Outpatient visits have been included in the register since 2001. RESULTS: We identified 98,770 patients (women n = 72,063; 73 %) with proximal humeral fractures between 2001 and 2012. In 2001, the sex-specific incidence of proximal humeral fractures was 134.5 per 100,000 person-years for women and 49.2 for men. In 2012, the corresponding values were 174.6 for women and 68.1 for men, increasing 30 % in women and 39 % in men. A total of 17,013 surgical procedures were conducted between 2001 and 2012. Open reduction and internal fixation with a plate was the most common procedure (n = 5050, 30 %), followed by endoprosthetic implantation (n = 3962, 23 %) and intramedullary nailing (n = 3376, 20 %). The proportion of surgically treated patients increased from 12.1 % in 2001 to 16.8 % in 2012 for women and from 15.1 % in 2001 to 17.1 % in 2012 for men. CONCLUSION: The Swedish national incidence of proximal humeral fractures has been increasing, although it seems to have peaked in the elderly population during 2008-2010. The rate of surgical treatment has increased substantially, particularly open reduction and internal fixation with a plate. To our knowledge, this is the first nationwide epidemiologic study for Sweden reporting the incidence of proximal humeral fractures and including all inpatient and outpatient visits.

Atrazine and malathion shorten the maturation process of Xenopus laevis oocytes and have an adverse effect on early embryo development.

The use of pesticides has a negative impact on the environment. Amphibians have long been regarded as indicator species to pollutants due to their permeable skin and sensitivity to the environment. Studies have shown that population declines of some amphibians are directly linked with exposure to agricultural contaminants. In the past, much of the studies have focused on the toxic effect of contaminants on larvae (tadpoles), juvenile and adult frogs. However, due to the nature of their life cycle, amphibian eggs and early embryos are especially susceptible to the contaminants, and any alteration during the early reproductive stages may have a profound effect on the health and population of amphibians. In this study, we analyzed the effect of atrazine and malathion, two commonly used pesticides, on Xenopus laevis oocyte maturation and early embryogenesis. We found that both atrazine and malathion shortened the frog oocyte maturation process and resulted in reduced Emi2 levels at cytostatic factor-mediated metaphase arrest, and a high level of Emi2 is critically important for oocyte maturation. Furthermore, frog embryos fertilized under the influence of atrazine and/or malathion displayed a higher rate of abnormal division that eventually led to embryo death during early embryogenesis.

The association between objectively measured physical activity and life-space mobility among older people.

The purpose of this cross-sectional study was to investigate the association between objectively measured physical activity and life-space mobility in community-dwelling older people. Life-space refers to the spatial area a person purposefully moves through in daily life (bedroom, home, yard, neighborhood, town, and beyond) and life-space mobility to the frequency of travel and the help needed when moving through different life-space areas. The study population comprised community-living 75- to 90-year-old people {n = 174; median age 79.7 [interquartile range (IQR) 7.1]}, participating in the accelerometer substudy of Life-Space Mobility in Old Age (LISPE) project. Step counts and activity time were measured by an accelerometer (Hookie "AM20 Activity Meter") for 7 days. Life-space mobility was assessed with Life-Space Assessment (LSA) questionnaire. Altogether, 16% had a life-space area restricted to the neighborhood when moving independently. Participants with a restricted life space were less physically active and about 70% of them had exceptionally low values in daily step counts (≤ 615 steps) and moderate activity time (≤ 6.8 min). Higher step counts and activity time correlated positively with life-space mobility. Prospective studies are needed to clarify the temporal order of low physical activity level and restriction in life-space mobility.

Genetic association of complement component 2 polymorphism with systemic lupus erythematosus.

Complement component 2 (C2), an early member of the classical pathway, mainly participates in apoptotic cell clearance. We hypothesize that C2 polymorphism may confer genetic susceptibility to complement dysfunction in systemic lupus erythematosus (SLE). The major aim of our study was to investigate the clinical and serological associations of C2 variants in Chinese patients with SLE. The single-nucleotide polymorphism (rs2844455, G/A SNP) located in the intron region of C2 gene was genotyped by direct sequencing in 95 SLE patients and 95 matched normal control subjects. The gene expression profiles were generated by quantitative real-time polymerase chain reaction (PCR) and reverse transcription PCR. Our results showed that the AA genotype was observed more frequently in SLE patients than in normal control subjects (22.1% vs 9.5%, P < 0.05). The A allele was strongly associated with the occurrence of hair loss, photosensitivity and anti-cardiolipin antibodies; whereas, the G allele was associated with lower frequencies of these clinical presentations. Relative expression levels were significantly lower in patients with the AA genotype [median: 18.86, interquartile range (IQR) 11.36-22.43, P = 0.002] than in those with the GG genotype (35.76, IQR: 19.33-49.71). As expected, we confirmed the A allele as a risk factor for SLE development in a Chinese population, in contrast, the G allele might be a protective factor against the pathogenic autoantibody formation and cutaneous manifestations in SLE patients.

Associations of the major international high-risk resistant clones and virulent clones with specific ompK36 allele groups in Klebsiella pneumoniae in Taiwan.

This study was conducted to investigate the association between ompK36 variants and international high-risk clones in Klebsiella pneumoniae. Fifty-nine sequence types (STs) divided into four ompK36 allele groups (groups A to D) were identified among 185 K. pneumoniae isolates. The major high-risk clones (29 ST11, 13 ST15, 7 ST37 and 1 ST147 isolates) were assigned to group A, while 6 STs (15 ST23, 2 ST65, 3 ST86, 1 ST163, 1 ST373 and 2 ST375 isolates) associated with pyogenic liver abscess were assigned to group C. The genotyping assay developed in this study may be useful for screening of epidemic STs.

Kinetically Selective Inhibitors of Histone Deacetylase 2 (HDAC2) as Cognition Enhancers.

Aiming towards the development of novel nootropic therapeutics to address the cognitive impairment common to a range of brain disorders, we set out to develop highly selective small molecule inhibitors of HDAC2, a chromatin modifying histone deacetylase implicated in memory formation and synaptic plasticity. Novel ortho-aminoanilide inhibitors were designed and evaluated for their ability to selectively inhibit HDAC2 versus the other Class I HDACs. Kinetic and thermodynamic binding properties were essential elements of our design strategy and two novel classes of ortho-aminoanilides, that exhibit kinetic selectivity (biased residence time) for HDAC2 versus the highly homologous isoform HDAC1, were identified. These kinetically selective HDAC2 inhibitors (BRD6688 and BRD4884) increased H4K12 and H3K9 histone acetylation in primary mouse neuronal cell culture assays, in the hippocampus of CK-p25 mice, a model of neurodegenerative disease, and rescued the associated memory deficits of these mice in a cognition behavioural model. These studies demonstrate for the first time that selective pharmacological inhibition of HDAC2 is feasible and that inhibition of the catalytic activity of this enzyme may serve as a therapeutic approach towards enhancing the learning and memory processes that are affected in many neurological and psychiatric disorders.

Functional implications of a psychiatric risk variant within CACNA1C in induced human neurons.

Psychiatric disorders have clear heritable risk. Several large-scale genome-wide association studies have revealed a strong association between susceptibility for psychiatric disorders, including bipolar disease, schizophrenia and major depression, and a haplotype located in an intronic region of the L-type voltage-gated calcium channel (VGCC) subunit gene CACNA1C (peak associated SNP rs1006737), making it one of the most replicable and consistent associations in psychiatric genetics. In the current study, we used induced human neurons to reveal a functional phenotype associated with this psychiatric risk variant. We generated induced human neurons, or iN cells, from more than 20 individuals harboring homozygous risk genotypes, heterozygous or homozygous non-risk genotypes at the rs1006737 locus. Using these iNs, we performed electrophysiology and quantitative PCR experiments that demonstrated increased L-type VGCC current density as well as increased mRNA expression of CACNA1C in iNs homozygous for the risk genotype, compared with non-risk genotypes. These studies demonstrate that the risk genotype at rs1006737 is associated with significant functional alterations in human iNs, and may direct future efforts at developing novel therapeutics for the treatment of psychiatric disease.

Ankyrin-G regulates neurogenesis and Wnt signaling by altering the subcellular localization of ß-catenin.

Ankyrin-G is a scaffolding protein required for the formation of the axon initial segment in neurons. Recent genome-wide association studies and whole-exome sequencing have identified ANK3, the gene coding for ankyrin-G, to be a risk gene for multiple neuropsychiatric disorders, such as bipolar disorder, schizophrenia and autism spectrum disorder. Here, we describe a novel role for ankyrin-G in neural progenitor proliferation in the developing cortex. We found that ankyrin-G regulates canonical Wnt signaling by altering the subcellular localization and availability of ß-catenin in proliferating cells. Ankyrin-G loss-of-function increases ß-catenin levels in the nucleus, thereby promoting neural progenitor proliferation. Importantly, abnormalities in proliferation can be rescued by reducing Wnt pathway signaling. Taken together, these results suggest that ankyrin-G is required for proper brain development.

The MZF1/c-MYC axis mediates lung adenocarcinoma progression caused by wild-type lkb1 loss.

Liver kinase B1 (LKB1) loss in lung adenocarcinoma is commonly caused by genetic mutations, but these mutations rarely occur in Asian patients. We recently reported wild-type LKB1 loss via the alteration of NKX2-1/p53-axis-promoted tumor aggressiveness and predicted poor outcomes in cases of lung adenocarcinoma. The mechanistic action of wild-type LKB1 loss within tumor progression remains unknown. The suppression of MYC by LKB1 controls epithelial organization; therefore, we hypothesize that MYC expression can be increased via wild-type LKB1 loss and promotes tumor progression. Here, MYC transcription is upregulated by LKB1-loss-mediated MZF1 expression. The wild-type LKB1-loss-mediated MZF1/MYC axis is responsible for soft-agar growth, migration and invasion in lung adenocarcinoma cells. Moreover, wild-type LKB1 loss-induced cell invasiveness was markedly suppressed by MYC inhibitors (10058-F4 and JQ1). Patients with low-LKB1/high-MZF1 or low-LKB1/high-MYC tumors have shorter overall survival and relapse-free-survival periods than patients with high-LKB1/low-MZF1 or high-LKB1/low-MYC tumors. In summary, MZF1-mediated MYC expression may promote tumor progression, resulting in poor outcomes in cases of lung adenocarcinoma with low-wild-type-LKB1 tumors.