Epistatic interactions between NMD and TRP53 control progenitor cell maintenance and brain size.

Mutations in human nonsense-mediated mRNA decay (NMD) factors are enriched in neurodevelopmental disorders. We show that deletion of key NMD factor Upf2 in mouse embryonic neural progenitor cells causes perinatal microcephaly but deletion in immature neurons does not, indicating NMD's critical roles in progenitors. Upf2 knockout (KO) prolongs the cell cycle of radial glia progenitor cells, promotes their transition into intermediate progenitors, and leads to reduced upper-layer neurons. CRISPRi screening identified Trp53 knockdown rescuing Upf2KO progenitors without globally reversing NMD inhibition, implying marginal contributions of most NMD targets to the cell cycle defect. Integrated functional genomics shows that NMD degrades selective TRP53 downstream targets, including Cdkn1a, which, without NMD suppression, slow the cell cycle. Trp53KO restores the progenitor cell pool and rescues the microcephaly of Upf2KO mice. Therefore, one physiological role of NMD in the developing brain is to degrade selective TRP53 targets to control progenitor cell cycle and brain size.

A novel class of inhibitors that disrupts the stability of integrin heterodimers identified by CRISPR-tiling-instructed genetic screens.

The plasma membrane is enriched for receptors and signaling proteins that are accessible from the extracellular space for pharmacological intervention. Here we conducted a series of CRISPR screens using human cell surface proteome and integrin family libraries in multiple cancer models. Our results identified ITGAV (integrin αV) and its heterodimer partner ITGB5 (integrin ß5) as the essential integrin α/ß pair for cancer cell expansion. High-density CRISPR gene tiling further pinpointed the integral pocket within the ß-propeller domain of ITGAV for integrin αVß5 dimerization. Combined with in silico compound docking, we developed a CRISPR-Tiling-Instructed Computer-Aided (CRISPR-TICA) pipeline for drug discovery and identified Cpd_AV2 as a lead inhibitor targeting the ß-propeller central pocket of ITGAV. Cpd_AV2 treatment led to rapid uncoupling of integrin αVß5 and cellular apoptosis, providing a unique class of therapeutic action that eliminates the integrin signaling via heterodimer dissociation. We also foresee the CRISPR-TICA approach to be an accessible method for future drug discovery studies.

The effectiveness and tolerability of pharmacotherapy for psychosis in 22q11.2 Deletion Syndrome: A systematic review.

OBJECTIVE: The 22q11.2 Deletion Syndrome (22q11.2DS) is the most common microdeletion in humans with over 180 phenotypic expressions. Approximately 30-40% of affected individuals will develop psychosis and 25% meet the criteria for schizophrenia. Despite this, pharmacotherapy for managing psychosis in 22q11.2DS is poorly understood and 22q11.2DS psychosis is frequently labelled as treatment resistant. The objectives of this paper are to evaluate the effectiveness and tolerability of pharmacotherapy for 22q11.2DS psychosis and evaluate the evidence for treatment resistance. METHOD: A systematic search was performed using CINAHL, The Cochrane Library (Cochrane Database of Systematic Reviews; Cochrane Central Register of Controlled Trials and Cochrane Clinical Answers), EMBASE, PsycINFO, PubMed, Scopus and Web of Science Core Collection from inception to December 2022. It yielded 39 case reports, 6 case series and 1 retrospective study which met the inclusion criteria. RESULTS: Based on the current literature, individuals with 22q11.2DS psychosis experience a greater rate of medical co-morbidities such as cardiac arrhythmias, seizures and movement disorders, which complicate pharmacotherapy. Poor tolerability rather than poor clinical response motivates the switching of antipsychotics, which may explain the labelling of treatment resistance in the literature. CONCLUSION: There are insufficient data to recommend a single antipsychotic for 22q11.2DS psychosis. Nonetheless, with proactive management of co-morbidities, antipsychotic medication in 22q11.2DS psychosis is an effective treatment commonly resulting in improvement in quality of life.

Therapeutic targeting Tudor domains in leukemia via CRISPR-Scan Assisted Drug Discovery.

Epigenetic dysregulation has been reported in multiple cancers including leukemias. Nonetheless, the roles of the epigenetic reader Tudor domains in leukemia progression and therapy remain unexplored. Here, we conducted a Tudor domain-focused CRISPR screen and identified SGF29, a component of SAGA/ATAC acetyltransferase complexes, as a crucial factor for H3K9 acetylation, ribosomal gene expression, and leukemogenesis. To facilitate drug development, we integrated the CRISPR tiling scan with compound docking and molecular dynamics simulation, presenting a generally applicable strategy called CRISPR-Scan Assisted Drug Discovery (CRISPR-SADD). Using this approach, we identified a lead inhibitor that selectively targets SGF29's Tudor domain and demonstrates efficacy against leukemia. Furthermore, we propose that the structural genetics approach used in our study can be widely applied to diverse fields for de novo drug discovery.

TP63 fusions drive multicomplex enhancer rewiring, lymphomagenesis, and EZH2 dependence.

Gene fusions involving tumor protein p63 gene (TP63) occur in multiple T and B cell lymphomas and portend a dismal prognosis for patients. The function and mechanisms of TP63 fusions remain unclear, and there is no target therapy for patients with lymphoma harboring TP63 fusions. Here, we show that TP63 fusions act as bona fide oncogenes and are essential for fusion-positive lymphomas. Transgenic mice expressing TBL1XR1::TP63, the most common TP63 fusion, develop diverse lymphomas that recapitulate multiple human T and B cell lymphomas. Here, we identify that TP63 fusions coordinate the recruitment of two epigenetic modifying complexes, the nuclear receptor corepressor (NCoR)-histone deacetylase 3 (HDAC3) by the N-terminal TP63 fusion partner and the lysine methyltransferase 2D (KMT2D) by the C-terminal TP63 component, which are both required for fusion-dependent survival. TBL1XR1::TP63 localization at enhancers drives a unique cell state that involves up-regulation of MYC and the polycomb repressor complex 2 (PRC2) components EED and EZH2. Inhibiting EZH2 with the therapeutic agent valemetostat is highly effective at treating transgenic lymphoma murine models, xenografts, and patient-derived xenografts harboring TP63 fusions. One patient with TP63-rearranged lymphoma showed a rapid response to valemetostat treatment. In summary, TP63 fusions link partner components that, together, coordinate multiple epigenetic complexes, resulting in therapeutic vulnerability to EZH2 inhibition.

Should psychiatrists support the availability of nicotine e-cigarettes in Australia?

OBJECTIVE: To examine the position statement of the Royal Australian and New Zealand College of Psychiatrists (RANZCP) regarding the availability of electronic cigarettes in Australia. CONCLUSION: There is limited evidence supporting the efficacy of nicotine e-cigarettes as an effective tobacco harm-reduction or cessation strategy for people with mental illness. The recommendations to increase their availability under regulation must be balanced with the physical and mental health risks of vapour inhalation and nicotine use, particularly for youth. Future recommendations by the RANZCP in relation to e-cigarettes must consider both the available evidence for harm reduction and the potential risks associated with youth e-cigarette use.

Engagement with perinatal mental health services: a cross-sectional questionnaire survey.

BACKGROUND: Perinatal depression and/or anxiety disorders are undertreated pregnancy complications. This is partly due to low rates of engagement by women. This study aimed to identify barriers and facilitators to women accessing perinatal mental health services in an outer metropolitan hospital in Queensland, Australia. METHODS: Data was collected from pregnant women through a cross-sectional survey. Women rated the extent certain factors influenced their engagement. Respondents were separated into three groups: women who were not offered a referral to perinatal mental health services, women who were offered a referral but did not engage, and women who engaged. RESULTS: A total of 218 women participated. A response rate of 71% was achieved. 38.1% of participants did not believe themselves knowledgeable about mental illness in the perinatal period, and 14.7% did not recall being asked about their mental health during their pregnancy. Of those participants who recalled being asked about their mental health, 37.1% were offered a referral. Of these, just over a third (36.2%) accepted, and out of this group, 40% attended an appointment. Regardless of referral and engagement status, the factors identified as influencing participant engagement were time restraints, lack of childcare support, and encouragement by family and health care professionals. Stigma was not identified as a barrier. CONCLUSIONS: Perinatal mental health service engagement could be improved by health services: ensuring universal screening and actively engaging women in the process: assisting with childcare; improving appointment immediacy and accessibility; and educating health care professionals about their influence on women's engagement.

Evolutionary dynamics of the human NADPH oxidase genes CYBB, CYBA, NCF2, and NCF4: functional implications.

The phagocyte NADPH oxidase catalyzes the reduction of O2 to reactive oxygen species with microbicidal activity. It is composed of two membrane-spanning subunits, gp91-phox and p22-phox (encoded by CYBB and CYBA, respectively), and three cytoplasmic subunits, p40-phox, p47-phox, and p67-phox (encoded by NCF4, NCF1, and NCF2, respectively). Mutations in any of these genes can result in chronic granulomatous disease, a primary immunodeficiency characterized by recurrent infections. Using evolutionary mapping, we determined that episodes of adaptive natural selection have shaped the extracellular portion of gp91-phox during the evolution of mammals, which suggests that this region may have a function in host-pathogen interactions. On the basis of a resequencing analysis of approximately 35 kb of CYBB, CYBA, NCF2, and NCF4 in 102 ethnically diverse individuals (24 of African ancestry, 31 of European ancestry, 24 of Asian/Oceanians, and 23 US Hispanics), we show that the pattern of CYBA diversity is compatible with balancing natural selection, perhaps mediated by catalase-positive pathogens. NCF2 in Asian populations shows a pattern of diversity characterized by a differentiated haplotype structure. Our study provides insight into the role of pathogen-driven natural selection in an innate immune pathway and sheds light on the role of CYBA in endothelial, nonphagocytic NADPH oxidases, which are relevant in the pathogenesis of cardiovascular and other complex diseases.

Lis1 reduction causes tangential migratory errors in mouse spinal cord.

Mutations in human LIS1 cause abnormal neuronal migration and a smooth brain phenotype known as lissencephaly. Lis1+/− (Pafah1b1) mice show defective lamination in the cerebral cortex and hippocampal formation, whereas homozygous mutations result in embryonic lethality. Given that Lis1 is highly expressed in embryonic neurons, we hypothesized that sympathetic and parasympathetic preganglionic neurons (SPNs and PPNs) would exhibit migratory defects in Lis1+/− mice. The initial radial migration of SPNs and PPNs that occurs together with somatic motor neurons appeared unaffected in Lis1+/− mice. The subsequent dorsally directed tangential migration, however, was aberrant in a subset of these neurons. At all embryonic ages analyzed, the distribution of SPNs and PPNs in Lis1+/− mice was elongated dorsoventrally compared with Lis1+/+ mice. Individual cell bodies of ectopic preganglionic neurons were found in the ventral spinal cord with their leading processes oriented along their dorsal migratory trajectory. By birth, Lis1+/− SPNs and PPNs were separated into distinct groups, those that were correctly, and those incorrectly positioned in the intermediate horn. As mispositioned SPNs and PPNs still were detected in P30 Lis1+/− mice, we conclude that these neurons ceased migration prematurely. Additionally, we found that a dorsally located group of somatic motor neurons in the lumbar spinal cord, the retrodorsolateral nucleus, showed delayed migration in Lis1+/− mice. These results suggest that Lis1 is required for the dorsally directed tangential migration of many sympathetic and parasympathetic preganglionic neurons and a subset of somatic motor neurons.

Disruption of telomerase trafficking by TCAB1 mutation causes dyskeratosis congenita.

Dyskeratosis congenita (DC) is a genetic disorder of defective tissue maintenance and cancer predisposition caused by short telomeres and impaired stem cell function. Telomerase mutations are thought to precipitate DC by reducing either the catalytic activity or the overall levels of the telomerase complex. However, the underlying genetic mutations and the mechanisms of telomere shortening remain unknown for as many as 50% of DC patients, who lack mutations in genes controlling telomere homeostasis. Here, we show that disruption of telomerase trafficking accounts for unknown cases of DC. We identify DC patients with missense mutations in TCAB1, a telomerase holoenzyme protein that facilitates trafficking of telomerase to Cajal bodies. Compound heterozygous mutations in TCAB1 disrupt telomerase localization to Cajal bodies, resulting in misdirection of telomerase RNA to nucleoli, which prevents telomerase from elongating telomeres. Our findings establish telomerase mislocalization as a novel cause of DC, and suggest that telomerase trafficking defects may contribute more broadly to the pathogenesis of telomere-related disease.

Maternal EPHX1 polymorphisms and risk of phenytoin-induced congenital malformations.

OBJECTIVES: The teratogenic effects of the anti-epileptic drug phenytoin have been linked to genetic differences in phenytoin disposition. The goal of this study was to assess the effect of maternal genotype of functional polymorphisms in two genes involved in phenytoin metabolism, CYP2C9 (R144C, I395L) and EPHX1 (Y113H, H139R), on the presence of major craniofacial abnormalities (CFAs) in the child. METHODS: We used data from the Collaborative Perinatal Project (1959-1974), a study involving 42 000 mothers and 55 000 children to assess the effect of maternal genotype. We studied 174 pregnancies in 155 women who used phenytoin throughout their pregnancy, gave birth to a live child and had available stored blood specimens suitable for DNA extraction. RESULTS: Nineteen children had CFA. In a logistic regression model adjusted for history of phenytoin use during the first trimester and maternal epilepsy (N=157 pregnancies), the maternal EPHX1 113 H [per rare allele odds ratio (OR): 2.43, 95% confidence interval (CI): 1.16-5.10, P=0.02] and 139 R (per rare allele OR: 2.33, 95% CI: 1.09-5.00, P=0.03) alleles were associated with CFAs in the child. The maternal EPHX1 Y113/H139 (common) haplotype showed a significant protective association with CFAs in the child (OR: 0.29, 95% CI: 0.12-0.68, P=0.004), when compared to other haplotypes. CYP2C9 genotype was not related to fetal endpoints. CONCLUSION: Maternal EPHX1 genotype may be associated with risk of fetal anomalies among pregnant women taking phenytoin. Future study is required to confirm these results in larger, independent populations.

Influence of cytotoxic T lymphocyte-associated antigen 4 (CTLA4) common polymorphisms on outcome in treatment of melanoma patients with CTLA-4 blockade.

Blockade of the cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), a down-regulator of T-cell activation, can cause cancer regression in patients with metastatic melanoma. However, not all patients respond well to the therapy and some develop severe autoimmune reactions. We hypothesized that common genetic variation in the CTLA4 gene could contribute to response to CTLA-4 blockade and the occurrence of autoimmune reactions. We investigated 7 common single nucleotide polymorphisms, SNPs, (rs733618, rs4553808, rs11571317, rs5742909, rs231775, rs3087243, and rs7565213) in 152 white melanoma patients who received CTLA-4 blockade. Three SNPs were associated with response to therapy: proximal promoter SNPs, rs4553808 [P=0.002; odds ratio (OR) 3.39; 95% confidence interval (CI), 1.62-7.10] and rs11571327 (P=0.02; OR 2.89; 95% CI, 1.23-6.83) and the nonsynonymous SNP rs231775 (Thr17Ala, P=0.009; OR 0.39; 95% CI, 0.18-0.82). A haplotype analysis including the 7 SNPs suggested that the common haplotype, TACCGGG could be associated with no response (P=0.02) whereas the haplotype TGCCAGG (P=0.06; OR 4.13; 95% CI, 1.17-14.5) could be associated with response to the treatment. No significant association was observed for occurrence of severe autoimmune reactions (grade III/IV) either by single SNP or haplotype analyses. Our results suggest that genetic variation in CTLA4 could influence response to CTLA-4 blockade therapy in metastatic melanoma patients, but further studies are necessary to confirm the observed associations.

Functional profiling of uncommon VCAM1 promoter polymorphisms prevalent in African American populations.

Multiple variants of the vascular adhesion molecule-1 (VCAM1) promoter show increased nucleotide heterozygosity in the African American population. Using a novel transfection-based transcriptional pathway profiling method, we show that select uncommon variants are functionally hyperactive. Eight candidate VCAM1 promoter haplotypes comprising 13 previously identified SNPs were assessed for response to known mitogens. Activity was correlated with bioinformatic analysis of hyper- and hyporesponsive variants to identify the gain or loss of haplotype-specific transcription factor binding site (TFBS). Using this approach, a low frequency regulatory allele (c.-540A>G; dbSNP rs3783605:A>G), found in a hyperactive VCAM1 promoter haplotype, was shown to create a candidate binding site for ETS2 that was confirmed in vivo by chromatin immunoprecipitation. This report provides the first functional evaluation of VCAM1 promoter polymorphisms and establishes a hypothetical foundation for investigation of their role in the pathogenesis of VCAM1-associated diseases that disproportionately afflict African Americans, including thromboembolic diseases, asthma, and multiple myeloma.

A common genetic variant in FCGR3A-V158F and risk of Kaposi sarcoma herpesvirus infection and classic Kaposi sarcoma.

Associations of FCGR3A among men with HIV/acquired immunodeficiency syndrome suggest that host responses affect the pathogenesis of Kaposi sarcoma herpesvirus (KSHV) infection and risk of acquired immunodeficiency syndrome-associated Kaposi sarcoma. Using DNA from two HIV seronegative case-control populations in Italy, we examined whether the functional FCGR3A-V158F variant was associated with risk of KSHV infection or classic Kaposi sarcoma (CKS). In population I, we examined FCGR3A variants and risk of KSHV infection in 34 KSHV latent nuclear antigen (LANA)-seropositive and 120 LANA-seronegative adults from Sardinia (52% male; median age, 45 years; range, 31-60), whereas in population II, we examined risk of CKS from 133 CKS cases and 172 KSHV LANA-seropositive controls from Sicily, Rome, and Naples (70% males; median age, 74 years; range, 29-91). FCGR3A variants were determined by direct sequence analysis of a nested PCR of genomic DNA assay using allele-specific primers. KSHV LANA was determined by immunofluorescence assay. Overall, compared with the 158F allele, 158V was overrepresented among controls from both Mediterranean populations (frequency = 0.52 and 0.51, respectively). After controlling for age, 158V homozygous women were at increased risk of KSHV infection and CKS compared with 158F homozygous women [odds ratio (OR), 8.7; 95% confidence interval (95% CI), 0.8-98 and OR, 3.8; 95% CI, 1.0-14, respectively], whereas homozygous men were at decreased risk (OR, 0.4; 95% CI, 0.1-2.3 and OR, 0.4; 95% CI, 0.2-0.8, respectively). Significant gene-dose effects were observed among men and women at risk for CKS (P(trend) < or = 0.05). Our findings suggest that gender differences could possibly modify the effect of FCGR3A on risk of KSHV infection and CKS. Additional studies are required to confirm these relationships and determine their etiologic significance.

Association between chronic disseminated candidiasis in adult acute leukemia and common IL4 promoter haplotypes.

Chronic disseminated candidiasis (CDC) is a form of Candida species infection observed primarily in patients with acute leukemia. To investigate possible genetic factors associated with CDC, we conducted a pilot study of 40 patients with both leukemia and CDC and 50 control patients with leukemia only. A common haplotype of the IL4 promoter (-1098T/-589C/-33C) was overrepresented in patients with CDC (P= .01; odds ratio [OR], 2.16), whereas another common haplotype (-1098T/-589T/-33T) appeared to be protective against CDC (P= .018; OR, 0.47). Genetic variants of IL4 could contribute to the development of CDC in patients with acute leukemia.