Two Japanese families with familial pancreatic cancer with suspected pathogenic variants of CDKN2A: a case report.

BACKGROUND: Germline mutations in CDKN2A result in Familial Atypical Multiple Mole Melanoma Syndrome (FAMMM) (OMIM #155,601), which is associated with an increased risk of pancreatic ductal adenocarcinoma and melanoma. FAMMM has been reported globally, but it is quite rare in Japan. We report two families with familial pancreatic cancer with suspected pathogenic variants of CDKN2A that were incidentally identified through comprehensive genomic profiling. CASE PRESENTATION: The first case is a 74-year-old woman with a diagnosis of pancreatic carcinoma with multiple liver metastases. She had family histories of pancreatic cancer, but no personal or family history of malignant melanoma. Whole exon sequencing detected a germline CDKN2A variant evaluated as likely pathogenic. The results were disclosed to her daughters after she died, and the same CDKN2A variant was detected in one of the daughter. The daughter was referred to a nearby hospital for her clinical management. The second case is a 65-year-old man with pancreatic ductal adenocarcinoma. He had family histories of pancreatic cancer, but no personal or family history of malignant melanoma. He underwent a comprehensive genomic profiling test using pancreatic cancer tissue, and detected a presumed germline pathogenic variant of CDKN2A. Germline testing confirmed the same CDKN2A variant. Genetic analysis of his relatives produced negative results. Other blood relatives are scheduled for genetic analysis in the future. We report two families with familial pancreatic cancer with suspected pathogenic variants of CDKN2A that were incidentally identified through comprehensive genomic profiling. CONCLUSIONS: In current Japanese precision medicine, comprehensive genetic analysis can reveal rare genetic syndromes and offer us the opportunity to provide health management for patients and their relatives. However, gene-specific issues are raised in terms of the evaluation of a variant's pathogenicity and the extent of surveillance of the at-risk organs due to a lack of genetic and clinical data concerning CDKN2A variant carriers in Japan.

Microsatellite instability is biased in Amsterdam II-defined Lynch-related cancer cases with family history but is rare in other cancers: a summary of 1000 analyses.

BACKGROUND: Microsatellite instability (MSI) is a key marker for predicting the response of immune checkpoint inhibitors (ICIs) and for screening Lynch syndrome (LS). AIM: This study aimed to see the characteristics of cancers with high level of MSI (MSI-H) in genetic medicine and precision medicine. METHODS: This study analyzed the incidence of MSI-H in 1000 cancers and compared according to several clinical and demographic factors. RESULTS: The incidence of MSI-H was highest in endometrial cancers (26.7%, 20/75), followed by small intestine (20%, 3/15) and colorectal cancers (CRCs)(13.7%, 64/466); the sum of these three cancers (15.6%) was significantly higher than that of other types (2.5%)(P < 0.0001). MSI-H was associated with LS-related cancers (P < 0.0001), younger age (P = 0.009), and family history, but not with smoking, drinking, or serum hepatitis virus markers. In CRC cases, MSI-H was significantly associated with a family history of LS-related cancer (P < 0.0001), Amsterdam II criteria [odds ratio (OR): 5.96], right side CRCs (OR: 4.89), and multiplicity (OR: 3.31). However, MSI-H was very rare in pancreatic (0.6%, 1/162) and biliary cancers (1.6%, 1/64) and was null in 25 familial pancreatic cancers. MSI-H was more recognized in cancers analyzed for genetic counseling (33.3%) than in those for ICI companion diagnostics (3.1%)(P < 0.0001). Even in CRCs, MSI-H was limited to 3.3% when analyzed for drug use. CONCLUSIONS: MSI-H was predominantly recognized in LS-related cancer cases with specific family histories and younger age. MSI-H was limited to a small proportion in precision medicine especially for non-LS-related cancer cases.

From population to neuron: exploring common mediators for metabolic problems and mental illnesses.

Major mental illnesses such as schizophrenia (SZ) and bipolar disorder (BP) frequently accompany metabolic conditions, but their relationship is still unclear, in particular at the mechanistic level. We implemented an approach of "from population to neuron", combining population-based epidemiological analysis with neurobiological experiments using cell and animal models based on a hypothesis built from the epidemiological study. We characterized high-quality population data, olfactory neuronal cells biopsied from patients with SZ or BP, and healthy subjects, as well as mice genetically modified for insulin signaling. We accessed the Danish Registry and observed (1) a higher incidence of diabetes in people with SZ or BP and (2) higher incidence of major mental illnesses in people with diabetes in the same large cohort. These epidemiological data suggest the existence of common pathophysiological mediators in both diabetes and major mental illnesses. We hypothesized that molecules associated with insulin resistance might be such common mediators, and then validated the hypothesis by using two independent sets of olfactory neuronal cells biopsied from patients and healthy controls. In the first set, we confirmed an enrichment of insulin signaling-associated molecules among the genes that were significantly different between SZ patients and controls in unbiased expression profiling data. In the second set, olfactory neuronal cells from SZ and BP patients who were not pre-diabetic or diabetic showed reduced IRS2 tyrosine phosphorylation upon insulin stimulation, indicative of insulin resistance. These cells also displayed an upregulation of IRS1 protein phosphorylation at serine-312 at baseline (without insulin stimulation), further supporting the concept of insulin resistance in olfactory neuronal cells from SZ patients. Finally, Irs2 knockout mice showed an aberrant response to amphetamine, which is also observed in some patients with major mental illnesses. The bi-directional relationships between major mental illnesses and diabetes suggest that there may be common pathophysiological mediators associated with insulin resistance underlying these mental and physical conditions.

Present status of germline findings in precision medicine for Japanese cancer patients: issues in the current system.

OBJECTIVE: Since 2019, precision cancer medicine has been covered by national insurance in Japan; however, to date, germline findings have not been fully reported. The aim of this study was to evaluate the current status and raise a problem of germline finding analysis and disclosure in Japanese precision cancer medicine. METHODS: Germline findings of 52 genes were examined in 296 cases with advanced cancer by a case series study. RESULTS: Six (2.0%) cases were examined by the Oncoguide™ NCC Oncopanel with germline testing, but no germline findings were reported. The remaining 290 (98.0%) cases were analyzed by FoundationOne® CDx (tumor-only testing), which recognized 404 pathogenic variants; those of BRCA1/2 were recognized in 16 (5.5%) tumors. Our institutional algorithm suggested 39 candidate germline findings in 34 cases, while the public algorithm listed at least 91 candidate germline findings. Four germline findings had been previously identified (BRCA1: 3 and ATM: 1). Nine of 30 cases with candidate germline findings excluding these known germline findings refused or deferred germline testing. Only 4 of 16 cases that received counseling underwent germline testing, and those 4 revealed 3 germline findings (BRCA2, CDK4 and RAD51C); in total, 8 (2.7%) germline findings were revealed. Reasons for refusing genetic counseling and/or germline testing included extra hospital visits, added expense for germline testing due to limited national insurance coverage, poor patient physical condition and no known family members associated with the possible germline finding. CONCLUSIONS: In current Japanese precision cancer medicine, only a small fraction of the patients undergoes germline testing and demonstrated germline finding. The current results suggested a need for earlier indications for precision cancer medicine, broader insurance coverage and more efficient germline finding prediction algorithms, to increase the number of germline testings and to improve the following managements.

New Insights and Potential Therapeutic Targeting of CB2 Cannabinoid Receptors in CNS Disorders.

The endocannabinoid system (ECS) is ubiquitous in most human tissues, and involved in the regulation of mental health. Consequently, its dysregulation is associated with neuropsychiatric and neurodegenerative disorders. Together, the ECS and the expanded endocannabinoidome (eCBome) are composed of genes coding for CB1 and CB2 cannabinoid receptors (CB1R, CB2R), endocannabinoids (eCBs), and the metabolic enzyme machinery for their synthesis and catabolism. The activation of CB1R is associated with adverse effects on the central nervous system (CNS), which has limited the therapeutic use of drugs that bind this receptor. The discovery of the functional neuronal CB2R raised new possibilities for the potential and safe targeting of the ECS for the treatment of CNS disorders. Previous studies were not able to detect CB2R mRNA transcripts in brain tissue and suggested that CB2Rs were absent in the brain and were considered peripheral receptors. Studies done on the role of CB2Rs as a potential therapeutic target for treating different disorders revealed the important putative role of CB2Rs in certain CNS disorders, which requires further clinical validation. This review addresses recent advances on the role of CB2Rs in neuropsychiatric and neurodegenerative disorders, including, but not limited to, anxiety, depression, schizophrenia, Parkinson's disease (PD), Alzheimer's disease (AD), Huntington's disease (HD) and addiction.

Disclosure of secondary findings in exome sequencing of 2480 Japanese cancer patients.

High-throughput sequencing has greatly contributed to precision medicine. However, challenges remain in reporting secondary findings (SFs) of germline pathogenic variants and managing the affected patients. The aim of this study was to examine the incidence of SFs in Japanese cancer patients using whole exome sequencing (WES) and to understand patient preferences regarding SF disclosure. WES was conducted for 2480 cancer patients. Genomic data were screened and classified for variants of 59 genes listed by the American College of Medical Genetics and Genomics SF v2.0 and for an additional 13 hereditary cancer-related genes. Majority of the participants (68.9%; 1709/2480) opted for disclosure of their SFs. Thirty-two pathogenic or likely pathogenic variants, including BRCA1 (7 patients), BRCA2 (4), CHEK2 (4), PTEN (3), MLH1 (3), SDHB (2), MSH6 (1), NF1 (1), EXT2 (1), NF1 (1), NTRK1 (1), MYH7 (3), MYL2 (1), TNNT2 (1), LDLR (2), FBN1 (1), and KCNH2 (1) were recognized in 36 patients (1.5%). Twenty-eight (77.8%) patients underwent genetic counseling and received their SF results. Eighteen (64.3%) patients underwent clinical management for SFs. Genetic validation tests were administered significantly more frequently to patients with than without a SF-related personal history (P = 0.025). This was a first attempt at a large-scale systematic exome analysis in Japan; nevertheless, many cancer patients opted for disclosure of SFs and accepted or considered clinical management.

Sharing genetic test results of germline pathogenic variants of hereditary cancer with relatives: A single-center cross-sectional study.

OBJECTIVE: This study aimed to determine whether Japanese cancer patients share test results of germline pathogenic variants of hereditary cancer with their relatives. METHODS: This single-center cross-sectional study enrolled 21 Japanese patients who received results of germline pathogenic variants of hereditary cancer at least 6 months prior. RESULTS: All patients shared their test results with at least one relative, with the following sharing rates: 85.7% for first-degree relatives, 10% for second-degree relatives and 8.3% for third-degree relatives. Patients most commonly shared the information with their children aged >18 years (86.7%), followed by their siblings (73.6%), spouses (64.7%) and parents (54.5%). Three categories were extracted from qualitative analysis: 'characteristics of my cancer', 'knowledge and caution about inheritability' and 'utilization of medical care.' CONCLUSIONS: The rate of test result sharing with first-degree relatives was comparable with those in Europe and the USA. Patients with germline pathogenic variants also tended to share their test results more with their children and siblings than with their parents. Informing their relatives of the results was suggestive of the motivation to influence their relatives' health outcome and contribute to the well-being of their children and siblings.

Metachronous ovarian endometrioid carcinomas in a patient with a PTEN variant: case report of incidentally detected Cowden syndrome.

BACKGROUND: Somatic PTEN mutation occurs in a proportion of ovarian endometrioid carcinomas. However, these cancers have seldom been reported in diseases associated with germline PTEN variants, such as Cowden syndrome (CS). CASE PRESENTATION: The present case was a 39-year-old woman with a left ovarian carcinoma who demonstrated a germline splice variant of PTEN (c.1026 + 1G > T) following genome-wide whole exome sequencing of her germline DNA. Histology of her resected tumor revealed endometrioid carcinoma of the same type as a right ovarian cancer resected eight years previously. These tumors showed null immunostaining for PTEN. She was genetically diagnosed with CS. Despite her clinical examinations had demonstrated several characteristic findings of CS, including mammary fibroma, esophageal and skin papilloma, colonic hamartoma, uterine myoma, and lipoma, the clinicians could not approach this diagnosis. CONCLUSION: Ovarian endometrioid carcinoma is generally thought to develop from endometrial tissue menstruated from the uterus and implanted on the ovary. To date, ovarian cancers have not been listed as CS-related cancers; however, ovarian endometrioid cancer can have a potential association with CS in endometriosis cases.

Pyridoxamine: A novel treatment for schizophrenia with enhanced carbonyl stress.

AIM: The aim of this clinical trial was to obtain proof of concept for high-dose pyridoxamine as a novel treatment for schizophrenia with enhanced carbonyl stress. METHODS: Ten Japanese schizophrenia patients with high plasma pentosidine, which is a representative biomarker of enhanced carbonyl stress, were recruited in a 24-week, open trial in which high-dose pyridoxamine (ranging from 1200 to 2400 mg/day) was administered using a conventional antipsychotic regimen. Main outcomes were the total change in Positive and Negative Syndrome Scale score and the Brief Psychiatric Rating Scale score from baseline to end of treatment at week 24 (or at withdrawal). RESULTS: Decreased plasma pentosidine levels were observed in eight patients. Two patients showed marked improvement in their psychological symptoms. A patient who harbors a frameshift mutation in the Glyoxalase 1 gene also showed considerable reduction in psychosis accompanied with a moderate decrease in plasma pentosidine levels. A reduction of greater than 20% in the assessment scale of drug-induced Parkinsonism occurred in four patients. Although there was no severe suicide-related ideation or behavior, Wernicke's encephalopathy-like adverse drug reactions occurred in two patients and were completely suppressed by thiamine supplementation. CONCLUSION: High-dose pyridoxamine add-on treatment was, in part, effective for a subpopulation of schizophrenia patients with enhanced carbonyl stress. Further randomized, placebo-controlled trials with careful monitoring will be required to validate the efficacy of high-dose pyridoxamine for these patients.

Cannabinoid CB2 Receptor Gene and Environmental Interaction in the Development of Psychiatric Disorders.

CB2 cannabinoid receptor (CB2R) gene is associated with depression. We investigated the gene-environment interaction between CB2R function and diverse stressors. First, anxiety-like behavior during chronic-mild-stress (CMS) was evaluated in C57BL/6JJmsSlc mice following treatment with CB2R agonist JWH015 or inverse-agonist AM630. Second, locomotor activity and anxiety-like behavior were measured following exposure to an immune poly I:C stressor. Gene expressions of HPA axis related molecules, Fkbp5, Nr3c1 and Crf and pro-inflammatory cytokine Il-1b, as well as Bdnf as a key neurotrophin that supports neuron health, function, and synaptic plasticity, were determined in hippocampus of Cnr2 knockout mice, as indicators of stressful environment. CMS-induced anxiety-like behavior was enhanced by AM630 and reduced by JWH015 and fluvoxamine. Poly I:C reduced locomotor activity and increased anxiety-like behavior, and these effects were pronounced in the heterozygote than in the wild type mice. Fkbp5 and Nr3c1 expression were lower in the Cnr2 heterozygotes than in the wild type mice with Poly I:C treatment. These findings indicate that interaction between CB2R gene and stressors increases the risk of depression-like behaviors that may be linked with neuro-immune crosstalk. Further studies in human subjects are necessary to determine the role of CB2R and environmental interaction in the development of depression.

A case of type 1 multiple endocrine neoplasia with esophageal stricture successfully treated with endoscopic balloon dilation and local steroid injection combined with surgical resection of gastrinomas.

BACKGROUND: In type 1 multiple endocrine neoplasia (MEN1), esophageal diseases association with excessive gastrin secretion in Zollinger-Ellison syndrome (ZES) sometimes develop. Here, we reported a case of MEN1/ZES, who developed dysphagia due to reflux esophagitis with severe esophageal stricture. Treatment for his esophageal stricture and ZES was discussed. CASE PRESENTATION: A 43-year-old man with progressive dysphagia and diarrhea was referred to the teaching hospital. He had a history of recurrent duodenojejunal perforations despite the anti-secretory medication. Blood examinations revealed elevated serum gastrin, calcium, and parathyroid hormone. Upper gastrointestinal endoscopy demonstrated a severe esophageal stricture, multiple gastroduodenal ulcer scars, and a duodenal submucosal tumor. Enhanced computed tomography showed multiple hypervascular tumors within the pancreas and duodenum, suggestive of MEN1. Genetic examination demonstrated a pathogenic MEN1 mutation. Repetitive endoscopic esophageal dilatation with intralesional corticosteroid injection, coupled with pancreatoduodenectomy were performed to improve the patient's symptoms and to treat pancreatic tumors. The histology of multiple tumors in the duodenum and pancreas were all consistent with neuroendocrine tumors. His hypergastrinemia subsided and he remained asymptomatic in his gastrointestinal tract after these treatments. CONCLUSION: For esophageal stenosis in case of MEN1/ZES, anti-secretory therapy and endoscopic dilatation with corticosteroid injection could be recommended. However, in refractory cases with repetitive and/or severe complications due to high acid secretion, surgical treatment could be considered as an option.

The regulation of soluble receptor for AGEs contributes to carbonyl stress in schizophrenia.

Our previous study showed that enhanced carbonyl stress is closely related to schizophrenia. The endogenous secretory receptor for advanced glycation end-products (esRAGE) is a splice variant of the AGER gene and is one of the soluble forms of RAGE. esRAGE is considered to be a key molecule for alleviating the burden of carbonyl stress by entrapping advanced glycation end-products (AGEs). In the current study, we conducted genetic association analyses focusing on AGER, in which we compared 212 schizophrenic patients to 214 control subjects. We also compared esRAGE levels among a subgroup of 104 patients and 89 controls and further carried out measurements of total circulating soluble RAGE (sRAGE) in 25 patients and 49 healthy subjects. Although the genetic association study yielded inconclusive results, multiple regression analysis indicated that a specific haplotype composed of rs17846798, rs2071288, and a 63 bp deletion, which were in perfect linkage disequilibrium (r2 = 1), and rs2070600 (Gly82Ser) were significantly associated with a marked decrease in serum esRAGE levels. Furthermore, compared to healthy subjects, schizophrenia showed significantly lower esRAGE (p = 0.007) and sRAGE (p = 0.03) levels, respectively. This is the first study to show that serum esRAGE levels are regulated by a newly identified specific haplotype in AGER and that a subpopulation of schizophrenic patients are more vulnerable to carbonyl stress.

Deficits in microRNA-mediated Cxcr4/Cxcl12 signaling in neurodevelopmental deficits in a 22q11 deletion syndrome mouse model.

22q11 deletion syndrome (22q11DS) frequently accompanies psychiatric conditions, some of which are classified as schizophrenia and bipolar disorder in the current diagnostic categorization. However, it remains elusive how the chromosomal microdeletion leads to the mental manifestation at the mechanistic level. Here we show that a 22q11DS mouse model with a deletion of 18 orthologous genes of human 22q11 (Df1/+ mice) has deficits in migration of cortical interneurons and hippocampal dentate precursor cells. Furthermore, Df1/+ mice show functional defects in Chemokine receptor 4/Chemokine ligand 12 (Cxcr4/Cxcl12; Sdf1) signaling, which reportedly underlie interneuron migration. Notably, the defects in interneuron progenitors are rescued by ectopic expression of Dgcr8, one of the genes in 22q11 microdeletion. Furthermore, heterozygous knockout mice for Dgcr8 show similar neurodevelopmental abnormalities as Df1/+ mice. Thus, Dgcr8-mediated regulation of microRNA is likely to underlie Cxcr4/Cxcl12 signaling and associated neurodevelopmental defects. Finally, we observe that expression of CXCL12 is decreased in olfactory neurons from sporadic cases with schizophrenia compared with normal controls. Given the increased risk of 22q11DS in schizophrenia that frequently shows interneuron abnormalities, the overall study suggests that CXCR4/CXCL12 signaling may represent a common downstream mediator in the pathophysiology of schizophrenia and related mental conditions.

Characterization of modified proteins in plasma from a subtype of schizophrenia based on carbonyl stress: Protein carbonyl is a possible biomarker of psychiatric disorders.

Although it's well known that protein carbonyl (PCO) and advanced glycation end-products (AGEs) levels are elevated in plasma from patients with renal dysfunction, we recently identified patients who had no renal dysfunction but possessed high levels of plasma pentosidine (PEN), which is an AGEs, and low vitamin B6 levels in serum. In this study, we investigated the status of carbonyl stress to characterize the subtype of schizophrenia. When plasma samples were subjected to Western blot analysis for various AGEs, clear differences were only observed with the anti-PEN antibody in the plasma from schizophrenic patients. Moreover, we determined the formation of protein carbonyl (PCO), a typical indicator of carbonyl stress, occurred prior to the accumulation of PEN in the plasma of schizophrenic patients. PCO levels in the plasma from schizophrenic patients were significantly higher than that from healthy subjects. Western blots analysis clearly showed that albumin and IgG were markedly carbonylated in the plasma of some patients. Thus, PCOs may be a novel marker of carbonyl stress-type schizophrenia in addition to albumin containing PEN structure.

NrCAM-regulating neural systems and addiction-related behaviors.

We have previously shown that a haplotype associated with decreased NrCAM expression in brain is protective against addiction vulnerability for polysubstance abuse in humans and that Nrcam knockout mice do not develop conditioned place preferences for morphine, cocaine or amphetamine. In order to gain insight into NrCAM involvement in addiction vulnerability, which may involve specific neural circuits underlying behavioral characteristics relevant to addiction, we evaluated several behavioral phenotypes in Nrcam knockout mice. Consistent with a potential general reduction in motivational function, Nrcam knockout mice demonstrated less curiosity for novel objects and for an unfamiliar conspecific, showed also less anxiety in the zero maze. Nrcam heterozygote knockout mice reduced alcohol preference and buried fewer marbles in home cage. These observations provide further support for a role of NrCAM in substance abuse including alcoholism vulnerability, possibly through its effects on behavioral traits that may affect addiction vulnerability, including novelty seeking, obsessive compulsion and responses to aversive or anxiety-provoking stimuli. Additionally, in order to prove glutamate homeostasis hypothesis of addiction, we analyzed glutamatergic molecules regulated by NRCAM expression. Glutaminase appears to be involved in NrCAM-related molecular pathway in two different tissues from human and mouse. An inhibitor of the enzyme, prolyl-leucyl-glycinamide, treatment produced, at least, some of the phenotypes of mice shown in alcohol preference and in anxiety-like behavior. Thus, NrCAM could affect addiction-related behaviors via at least partially modulation of some glutamatergic pathways and neural function in brain.

Carbonyl stress and schizophrenia.

Appropriate biological treatment and psychosocial support are essential to achieve and maintain recovery for patients with schizophrenia. Despite extensive efforts to clarify the underlying disease mechanisms, the main cause and pathophysiology of schizophrenia remain unclear. This is due in large part to disease heterogeneity, which results in biochemical differences within a single disease entity. Other factors include variability across clinical symptoms and disease course, along with varied risk factors and treatment responses. Although schizophrenia's positive symptoms are largely managed through treatment with atypical antipsychotics, new classes of drugs are needed to address the unmet medical need for improving cognitive dysfunction and promoting recovery of negative symptoms in these patients. Accumulation of toxic reactive dicarbonyls, such as methylglyoxal, are typical indicators of carbonyl stress, and result in the modification of proteins and the formation of advanced glycation end products, such as pentosidine. In June 2010, we reported on idiopathic carbonyl stress in a subpopulation of schizophrenia patients, leading to a failure of metabolic systems with plasma pentosidine accumulation and serum pyridoxal depletion. Our findings suggest two markers, pentosidine and pyridoxal, as beneficial for distinguishing a specific subgroup of schizophrenics. We believe that this information, derived from in vitro and in vivo studies, is beneficial in the search for personalized and hopefully more effective treatment regimens in schizophrenia. Here, we define a subtype of schizophrenia based on carbonyl stress and the potential for using carbonyl stress as a biomarker in the challenge of overcoming heterogeneity in schizophrenia treatment.

Cannabinoid CB2 receptors and hypersensitivity to methamphetamine: Vulnerability to schizophrenia.

The human cannabinoid receptor 2 (CB2R) gene CNR2 has been associated with schizophrenia development. Inbred mice treated with the CB2R inverse agonist AM630 and challenged with methamphetamine (MAP) showed reduced prepulse inhibition (%PPI) response and locomotor hyperactivity, both behavioral measures in rodents that correlate with psychosis. Mice lacking CB2R on striatal dopaminergic neurons exhibit a hyperdopaminergic tone and a hyperactivity phenotype. Hyperdopaminergia plays a role in the etiology of schizophrenia. This study aimed to determine the direct role of CB2R, heterozygous Cnr2 gene knockout (Het) mice treated with MAP to induce behavioral sensitivity mimicking a schizophrenia-like human phenotype. Additionally, the study aims to explore the unique modulation of dopamine activity by neuronal CB2R. Conditional knockout DAT-Cnr2-/- mice were evaluated in response to MAP treatments for this purpose. Sensorimotor gating deficits in DAT-Cnr2-/- mice were also evaluated. Het mice developed reverse tolerance (RT) to MAP-enhanced locomotor activity, and RT reduced the %PPI compared to wild-type (WT) mice. DAT-Cnr2-/- mice showed an increased sensitivity to stereotypical behavior induced by MAP and developed RT to MAP. DAT-Cnr2-/- mice exhibit a reduction in %PPI and alter social interaction, another core symptom of schizophrenia. These results demonstrate that there is an interaction between neuronal CB2R and MAP treatment, which increases the risk of schizophrenia-like behavior in this mouse model. This finding provides evidence for further studies targeting CB2R as a potential schizophrenia therapy.

A Cross-sectional Study of Regret in Cancer Patients After Sharing Test Results for Pathogenic Germline Variants of Hereditary Cancers With Relatives.

BACKGROUND: Research on whole genome/exome sequencing is increasing worldwide. However, challenges are emerging in relation to receiving germline pathogenic variant results and sharing them with relatives. OBJECTIVE: The aim of this study was to investigate the occurrence of and reasoning related to regret among patients with cancer who shared single-gene testing results and whole exome sequencing with family members. METHODS: This was a single-center, cross-sectional study. The Decision Regret Scale was administered, and descriptive questionnaires were used with 21 patients with cancer. RESULTS: Eight patients were classified as having no regret, 9 patients were classified as having mild regret, and 4 patients were classified as having moderate to strong regret. Reasons patients felt that sharing was the right decision included the following: to allow relatives and children to take preventive measures, the need for both parties to be aware of and ready for the hereditary transmission of cancer, and the need to be able to discuss the situation with others. On the other hand, some patients did not think it was a good decision to share the information because of the associated anxiety. CONCLUSIONS: Regret over sharing test results for pathogenic germline variants of hereditary cancers with relatives tended to be low. The main reason was that patients believed that they were able to benefit others by sharing. IMPLICATIONS FOR PRACTICE: Healthcare professionals need to understand the postsharing perceptions and experiences of patients and support them throughout the sharing process.

Comparative analysis of tumor content estimation methods based on simu- lated tumor samples identified their impact on somatic variant detection in cancer whole genome sequencing.

Whole genome sequencing (WGS) in cancer genomics has become widespread with recent technological innovations, and the amount and types of information obtained from WGS are increasing rapidly. Appropriate interpretation of results is becoming increasingly important in clinical applications. This study aimed to evaluate the accuracy of tumor content estimation and its impact on somatic variant detection, using 100 simulated tumor samples covering 10-100% tumor content constructed from the sequencing data of cell line models. Extensive analysis revealed that the estimation results varied among computational analytical methods. Notably, there was a large discrepancy in low tumor content (≤ 30%). The reproducibility decreased in cases wherein chromosome-scale copy number changes were observed in normal cells. The minimum tumor content required to detect somatic alterations was estimated to be 10-30%. Identification of whole genome doubling was achieved with the lowest tumor content, followed by single nucleotide variation/insertion or deletion, structural variation, and copy number variation. Tumor content had a significantly higher impact on the false negatives than the false positives in variant calls. Results should be interpreted cautiously for samples wherein tumor content is a concern. These results can form the basis of developing important guidelines for evaluating cancer WGS.

Association of SNPs linked to increased expression of SLC1A1 with schizophrenia.

Glutamate is one of the key molecules involved in signal transduction in the brain, and dysfunction of glutamate signaling could be linked to schizophrenia. The SLC1A1 gene located at 9p24 encodes the glutamate transporter EAAT3/EAAC1. To investigate the association between the SLC1A1 gene and schizophrenia in the Japanese population, we genotyped 19 tagging single nucleotide polymorphisms (tagSNPs) in the SLC1A1 gene in 576 unrelated individuals with schizophrenia and 576 control subjects followed by replication in an independent case-control study of 1,344 individuals with schizophrenia and 1,344 control subjects. In addition, we determined the boundaries of the copy number variation (CNV) region in the first intron (Database of Genomic Variants, chr9:4516796-4520549) and directly genotyped the CNV because of significant deviation from the Hardy-Weinberg equilibrium. The CNV was not associated with schizophrenia. Four SNPs showed a possible association with schizophrenia in the screening subjects and the associations were replicated in the same direction (nominal allelic P < 0.05), and, among them, an association with rs7022369 was replicated even after Bonferroni correction (allelic nominal P = 5 × 10(-5) , allelic corrected P = 2.5 × 10(-4) , allelic odds ratio, 1.30; 95% CI: 1.14-1.47 in the combined subjects). Expression analysis quantified by the real-time quantitative polymerase chain reaction in the postmortem prefrontal cortex of 43 Japanese individuals with schizophrenia and 11 Japanese control subjects revealed increased SLC1A1 expression levels in individuals homozygous for the rs7022369 risk allele (P = 0.003). Our findings suggest the involvement of SLC1A1 in the pathogenesis of schizophrenia.