Glial Markers of Suicidal Behavior in the Human Brain-A Systematic Review of Postmortem Studies.

Suicide is a major public health priority, and its molecular mechanisms appear to be related to glial abnormalities and specific transcriptional changes. This study aimed to identify and synthesize evidence of the relationship between glial dysfunction and suicidal behavior to understand the neurobiology of suicide. As of 26 January 2024, 46 articles that met the inclusion criteria were identified by searching PubMed and ISI Web of Science. Most postmortem studies, including 30 brain regions, have determined no density or number of total Nissl-glial cell changes in suicidal patients with major psychiatric disorders. There were 17 astrocytic, 14 microglial, and 9 oligodendroglial studies using specific markers of each glial cell and further on their specific gene expression. Those studies suggest that astrocytic and oligodendroglial cells lost but activated microglia in suicides with affective disorder, bipolar disorders, major depression disorders, or schizophrenia in comparison with non-suicided patients and non-psychiatric controls. Although the data from previous studies remain complex and cannot fully explain the effects of glial cell dysfunction related to suicidal behaviors, they provide risk directions potentially leading to suicide prevention.

Decreased ß-hydroxybutyrate and ketogenic amino acid levels in depressed human adults.

ß-hydroxybutyrate (BHB) is a major ketone body synthesized mainly in the liver mitochondria and is associated with stress and severity of depression in humans. It is known to alleviate depressive-like behaviors in mouse models of depression. In this study, plasma BHB, ketogenic and glucogenic amino acids selected from the Tohoku Medical Megabank Project Community-Based Cohort Study were analysed and measured using nuclear magnetic resonance spectroscopy. The Center for Epidemiologic Studies Depression Scale (CES-D) was utilized to select adult participants with depressive symptoms (CES-D ≥ 16; n = 5722) and control participants (CES-D < 16; n = 18,150). We observed significantly reduced plasma BHB, leucine, and tryptophan levels in participants with depressive symptoms. Using social defeat stress (SDS) mice models, we found that BHB levels in mice sera increased after acute SDS, but showed no change after chronic SDS, which differed from human plasma results. Furthermore, acute SDS increased mitochondrial BHB levels in the prefrontal cortex at 6 h. In contrast, chronic SDS significantly increased the amount of food intake but reduced hepatic mitochondrial BHB levels in mice. Moreover, gene transcriptions of voltage-dependent anion-selective channel 1 (Vdac1) and monocarboxylic acid transporter 1 (Mct1), major molecules relevant to mitochondrial biogenesis and BHB transporter, significantly decreased in the liver and PFC after chronic SDS exposure. These results provide evidence that hepatic and prefrontal mitochondrial biogenesis plays an important role in BHB synthesis under chronic stress and in humans with depressive symptoms.

N-Acetylcysteine Suppresses Microglial Inflammation and Induces Mortality Dose-Dependently via Tumor Necrosis Factor-α Signaling.

N-acetylcysteine (NAC) is an antioxidant that prevents tumor necrosis factor (TNF)-α-induced cell death, but it also acts as a pro-oxidant, promoting reactive oxygen species independent apoptosis. Although there is plausible preclinical evidence for the use of NAC in the treatment of psychiatric disorders, deleterious side effects are still of concern. Microglia, key innate immune cells in the brain, play an important role in inflammation in psychiatric disorders. This study aimed to investigate the beneficial and deleterious effects of NAC on microglia and stress-induced behavior abnormalities in mice, and its association with microglial TNF-α and nitric oxide (NO) production. The microglial cell line MG6 was stimulated by Escherichia coli lipopolysaccharide (LPS) using NAC at varying concentrations for 24 h. NAC inhibited LPS-induced TNF-α and NO synthesis, whereas high concentrations (≥30 mM) caused MG6 mortality. Intraperitoneal injections of NAC did not ameliorate stress-induced behavioral abnormalities in mice, but high-doses induced microglial mortality. Furthermore, NAC-induced mortality was alleviated in microglial TNF-α-deficient mice and human primary M2 microglia. Our findings provide ample evidence for the use of NAC as a modulating agent of inflammation in the brain. The risk of side effects from NAC on TNF-α remains unclear and merits further mechanistic investigations.

Deficient Autophagy in Microglia Aggravates Repeated Social Defeat Stress-Induced Social Avoidance.

Major depressive disorder (MDD) is associated with repeated exposure to environmental stress. Autophagy is activated under various stress conditions that are associated with several diseases in the brain. This study was aimed at elucidating the autophagy signaling changes in the prefrontal cortex (PFC) under repeated social defeat (RSD) to investigate the involvement of microglial autophagy in RSD-induced behavioral changes. We found that RSD stress, an animal model of MDD, significantly induced initial autophagic signals followed by increased transcription of autophagy-related genes (Atg6, Atg7, and Atg12) in the PFC. Similarly, significantly increased transcripts of ATGs (Atg6, Atg7, Atg12, and Atg5) were confirmed in the postmortem PFC of patients with MDD. The protein levels of the prefrontal cortical LC3B were significantly increased, whereas p62 was significantly decreased in the resilient but not in susceptible mice and patients with MDD. This indicates that enhanced autophagic flux may alleviate stress-induced depression. Furthermore, we identified that FKBP5, an early-stage autophagy regulator, was significantly increased in the PFC of resilient mice at the transcript and protein levels. In addition, the resilient mice exhibited enhanced autophagic flux in the prefrontal cortical microglia, and the autophagic deficiency in microglia aggravated RSD-induced social avoidance, indicating that microglial autophagy involves stress-induced behavioral changes.

A single nucleotide polymorphism (-250 A/C) of the GFAP gene is associated with brain structures and cerebral blood flow.

AIM: Glial fibrillary acidic protein (GFAP), the intermediate filament protein expressed in astrocytes, plays a key role in many aspects of brain function through communication with neurons or blood vessels. A common single nucleotide polymorphism (SNP), GFAP -250 C/A (rs2070935), is associated with the transcriptional regulation of GFAP, which can potentially result in the genotype-specific brain structure. This study aimed to verify the biological effects of the GFAP variants on brain structure and function. METHODS: We investigated the associations between the GFAP variants and magnetic resonance imaging findings, including gray and white matter volumes, white matter integrity, and resting arterial blood flow, from 1212 healthy Japanese subjects. RESULTS: The GFAP -250 C/A genotype was significantly associated with total gray matter volume, total white matter volume, average mean diffusivity, and mean cerebral blood flow. In voxel-by-voxel analyses, the GFAP genotype showed significant associations with the regional gray and white matter volumes in the inferior frontal lobe and corpus callosum, the regional mean diffusivity in the left posterior region, and the regional cerebral blood flow throughout the brain. CONCLUSION: This study revealed a common SNP that is significantly associated with multiple global brain structure parameters.

Isolation of Aspergillus caninus (Synonym: Phialosimplex caninus) from a Canine Iliac Lymph node.

Aspergillus caninus (synonym: Phialosimplex caninus) is an anamorphic fungus species associated with systemic infections in dogs that has been transferred from the genus Phialosimplex to Aspergillus. Here, we report the first case of canine A. caninus infection in Japan. A castrated Japanese Shiba Inu (6 years old; weight, 12.5 kg) was referred to the Yamaguchi University Animal Medical Center, Yamaguchi, Japan, in June 2017 showing vitality loss and depression. Computed tomography revealed iliac and splenic hilum lymphopathies, and histologic examination of an iliac lymph node by biopsy revealed granulomatous lesions with numerous oval to round yeast-like fungal cells. Aspergillus caninus was isolated from the biopsy samples, and in vitro susceptibility tests of the isolate to the antifungal drugs amphotericin B (AMB), fluconazole (FLZ), itraconazole (ITZ), voriconazole (VRZ), and micafungin (MCF) were performed by the E-test method. The isolate from this dog exhibited a minimal inhibitory concentration of < 0.002 µg/ml to AMB, > 256 µg/ml to FLZ, < 0.002 µg/ml to ITZ, < 0.002 µg/ml to VRZ, and < 0.002 µg/ml to MCF, indicating that the isolate was not susceptible to FLZ and susceptible to AMB, ITZ, VRZ, and MCF. Since the response of the patient dog to ITZ and VRZ treatments was poor, more aggressive management using combination therapies of ITZ with other antifungals may be necessary for treating canine A. caninus infection in dogs.

Polymorphisms in the microglial marker molecule CX3CR1 affect the blood volume of the human brain.

AIM: CX3CR1, a G-protein-coupled receptor, is involved in various inflammatory processes. Two non-synonymous single nucleotide polymorphisms, V249I (rs3732379) and T280M (rs3732378), are located in the sixth and seventh transmembrane domains of the CX3CR1 protein, respectively. Previous studies have indicated significant associations between T280M and leukocyte functional characteristics, including adhesion, signaling, and chemotaxis, while the function of V249I is unclear. In the brain, microglia are the only proven and widely accepted CX3CR1-expressing cells. This study aimed to specify whether there were specific brain regions on which these two single nucleotide polymorphisms exert their biological impacts through their functional effects on microglia. METHODS: Associations between the single nucleotide polymorphisms and brain characteristics, including gray and white matter volumes, white matter integrity, resting arterial blood volume, and cerebral blood flow, were evaluated among 1300 healthy Japanese individuals. RESULTS: The major allele carriers (V249 and T280) were significantly associated with an increased total arterial blood volume of the whole brain, especially around the bilateral precuneus, left posterior cingulate cortex, and left posterior parietal cortex. There were no significant associations between the genotypes and other brain structural indicators. CONCLUSION: This finding suggests that the CX3CR1 variants may affect arterial structures in the brain, possibly via interactions between microglia and brain microvascular endothelial cells.

Microglial production of TNF-alpha is a key element of sustained fear memory.

The proinflammatory cytokine productions in the brain are altered in a process of fear memory formation, indicating a possibility that altered microglial function may contribute to fear memory formation. We aimed to investigate whether and how microglial function contributes to fear memory formation. Expression levels of M1- and M2-type microglial marker molecules in microglia isolated from each conditioned mice group were assessed by real-time PCR and immunohistochemistry. Levels of tumor necrosis factor (TNF)-α, but not of other proinflammatory cytokines produced by M1-type microglia, increased in microglia from mice representing retention of fear memory, and returned to basal levels in microglia from mice representing extinction of fear memory. Administration of inhibitors of TNF-α production facilitated extinction of fear memory. On the other hand, expression levels of M2-type microglia-specific cell adhesion molecules, CD206 and CD209, were decreased in microglia from mice representing retention of fear memory, and returned to basal levels in microglia from mice representing extinction of fear memory. Our findings indicate that microglial TNF-α is a key element of sustained fear memory and suggest that TNF-α inhibitors can be candidate molecules for mitigating posttraumatic reactions caused by persistent fear memory.

Expression of organic anion-transporting polypeptide 1A2 and organic cation transporter 6 as a predictor of pathologic response to neoadjuvant chemotherapy in triple negative breast cancer.

Organic anion-transporting polypeptide 1A2 (OATP1A2) and organic cation transporter 6 (OCT6) are involved in the uptake of taxanes and anthracyclines, respectively. The aim of this study was to evaluate expression levels of OATP1A2 and OCT6 as a predictor of response to neoadjuvant chemotherapy (NAC) in breast cancer. A total of 124 patients who received anthracycline/taxane-based NAC were included. Expression levels of OATP1A2 and OCT6 were immunohistochemically assessed in core needle biopsies obtained prior to NAC. A pathologic good response (pGR) and a pathologic complete response (pCR) were achieved in 24 and 10 % of patients, respectively. In univariate analysis of the entire cohort, negative hormone receptor (HR) status (pGR and pCR, P < 0.001), high Ki-67 level (pGR, P = 0.03; pCR, P = 0.02), triple negative (TN) subtype (pGR, P = 0.001; pCR, P < 0.001), and high OCT6 (pGR, P = 0.003) were associated with the response. In combined analysis, high OATP1A2/high OCT6 level was also a significant factor for pGR (P = 0.001) and pCR (P = 0.001). Two separate multivariate analyses showed that HR status, TN subtype and combined high OATP1A2/high OCT6 level were significant independent predictors. When TN and non-TN tumors were assessed separately in univariate analysis, high Ki-67 level (P = 0.04) were associated with pGR and combined high OATP1A2/high OCT6 level was associated with both pGR (P = 0.005) and pCR (P = 0.03) in the TN group. Multivariate analysis identified the combined high OATP1A2/high OCT6 level as the sole independent predictor of pGR. In the non-TN group, negative HR status (P = 0.03) and positive HER2 status (P = 0.005) were associated with pGR, but HER2 status was the sole independent predictor of pGR. These results suggest that response-associated predictors may differ between the TN and non-TN tumors. Combined high OATP1A2/high OCT6 may be a potential predictor of response to anthracycline/taxane-based chemotherapy in breast cancer, especially in TN tumors.

The bioconversion of dietary α-linolenic acid to eicosapentaenoic acid in Bombyx mori.

n-3 Long-chain polyunsaturated fatty acids (n-3 LC-PUFAs), including eicosapentaenoic acid (EPA), are essential multifunctional nutrients in animals. Microorganisms such as microalgae are known to be n-3 LC-PUFA producers in aquatic environments. Various aquatic invertebrates, including Harpacticoida copepods, and a few terrestrial invertebrates, such as the nematode Caenorhabditis elegans, possess n-3 LC-PUFA biosynthetic enzymes. However, the capacity for n-3 LC-PUFA biosynthesis and the underlying molecular mechanisms in terrestrial insects are largely unclear. In this study, we investigated the fatty acid biosynthetic pathway in the silkworm Bombyx mori and found that EPA was present in silkworms throughout their development. Stable isotope tracing revealed that dietary α-linolenic acid (ALA) was metabolized to EPA in silkworm larvae. These results indicated that silkworms synthesize EPA from ALA. Given that EPA is enriched in the central nervous system, we propose that EPA confers optimal neuronal functions, similar to docosahexaenoic acid, in the mammalian nervous system.

Association Between Dementia, Change in Home-Care Use, and Depressive Symptoms During the COVID-19 Pandemic: A Longitudinal Study Using Data from Three Cohort Studies.

Background: The emotional impact of the coronavirus disease 2019 (COVID-19) pandemic on people with dementia has been quantified. However, little is known about the impact of change in home-care use owing to the pandemic. Objective: To determine the longitudinal association between dementia, change in home-care use, and depressive symptoms during the pandemic. Methods: We included data of 43,782 home-dwelling older adults from the English Longitudinal Study of Ageing (ELSA), Study of Health, Ageing and Retirement in Europe (SHARE), and National Health and Aging Trends Study (NHATS). This study considered the latest main wave survey prior to the pandemic as the baseline, and the COVID-19 survey as follow-up. In a series of coordinated analyses, multilevel binomial logistic regression model was used to examine the association between baseline dementia, change in home-care use at follow-up, and presence of depressive symptoms. Results: Dementia, using the ELSA, SHARE, and NHATS datasets, was identified in 2.9%, 2.3%, and 6.5% of older adults, and home-care use reduced in 1.7%, 2.8%, and 1.1% of individuals with dementia, respectively. Dementia was significantly associated with the increased risk of depressive symptoms in all three cohorts. However, the interaction between dementia and period (follow-up) was non-significant in SHARE and NHATS. Across all three cohorts, home-care use during the pandemic, regardless of change in amount, was significantly associated with increased depressive symptoms, compared to the non-use of home care. Conclusions: These results highlight the need for tailoring dementia care at home to promote independence and provide sustainable emotional support.

The effect of indium(III) triflate in oxone-mediated oxidative methyl esterification of aldehydes.

An oxidative methyl esterification of aldehydes was effectively achieved. The trivalent indium reagent, indium(III) triflate, was revealed to accelerate the reactions in many cases. Aromatic aldehydes with various substituents were subjected to this method, and each produced the corresponding methyl esters in good to excellent yields within a relatively short reaction time.

Place of death from dementia as an underlying cause during the COVID-19 pandemic in Japan: a cross-sectional study from national death certificates.

Background: The coronavirus disease (COVID-19) pandemic has challenged palliative end-of-life care for people with dementia. The site of death can be considered as an end-of-life care quality indicator. Most people with dementia prefer to die at nursing or private homes; however, in Japan, they are often hospitalized in psychiatric hospitals for management of neuropsychiatric symptoms. As palliative end-of-life care for older adults with Alzheimer's disease and related dementias has been further challenged by the COVID-19 pandemic, little is known about its effects on the place of death in patients with dementia. Objectives: This study aimed to investigate the shifts in place of death from dementia during the COVID-19 pandemic in Japan. Changes throughout the pandemic were compared between deaths from dementia and from senility. Design: Cross-sectional. Methods: Death certificate data of individuals aged 65 years or older who died in Japan between 1 January 2018, and 31 December 2021, were used to extract the cause and place of death. Differences in place of death between the periods were estimated using multinomial logistic analysis with reference to death in private homes. Results: Deaths from dementia mostly occurred in hospitals (59%), while deaths from senility were most frequent in nursing homes (37%). After adjusting for patient characteristics, the likelihood of hospital deaths significantly increased for patients with dementia during the pandemic. Meanwhile, the likelihood of senility deaths decreased in hospitals but increased in nursing homes during the pandemic. Conclusion: The shift to hospital deaths since the onset of the COVID-19 pandemic was uniquely observed in deaths from dementia. This hospital shift likely involved increased transfers from nursing and private homes to psychiatric hospitals. Further investigation is needed to examine the association between the pandemic-related change in long-term care workforce and palliative care practice in people with dementia.

Quality of End-of-Life Care for Older Adults with Dementia during the COVID-19 Pandemic.

OBJECTIVES: End-of-life (EOL) care during the coronavirus disease 2019 (COVID-19) pandemic has been a concern under the overwhelming pressure of health care service systems. People with dementia often receive suboptimal EOL care; thus, they may be at particular risk of poor care quality during the COVID-19 pandemic. This study investigated the interaction between dementia and pandemic on the proxies' overall ratings and ratings for 13 indicators. DESIGN: A longitudinal study. SETTING AND PARTICIPANTS: Data were collected from 1050 proxies for deceased participants in the National Health and Aging Trends Study, a nationally representative sample of community-dwelling Medicare beneficiaries aged ≥65 years. Participants were included if they had died between 2018 and 2021. METHODS: Participants were categorized into 4 groups depending on the period of death (before vs during the COVID-19 pandemic) and having no vs probable dementia, as defined by a previously validated algorithm. The quality of EOL care was assessed through postmortem interviews with bereaved caregivers. Multivariable binomial logistic regression analyses were performed to examine the main effects of dementia and pandemic period, and the interaction between dementia and pandemic on ratings of quality indicators. RESULTS: A total of 423 participants had probable dementia at the baseline. People with dementia who died were less likely to talk about religion in the last month of life than those without dementia. Decedents during the pandemic were more likely to have an overall rating of care as being not excellent than those before the onset of the pandemic. However, the interaction between dementia and pandemic was not significant in the 13 indicators and the overall rating of EOL care quality. CONCLUSION AND IMPLICATIONS: Most EOL care indicators preserved the level of quality, regardless of dementia and the COVID-19 pandemic. Disparities in spiritual care may exist across people with and without dementia.

Association between advance care planning and depressive symptoms among community-dwelling people with dementia: An observational cross-sectional study during the COVID-19 pandemic in Japan.

Objectives: Advance care planning (ACP) is an increasing priority for people with dementia during the COVID-19 pandemic. This study evaluated the association between ACP initiation and depressive symptoms among home-dwelling people living with dementia. Methods: An internet-based questionnaire survey was conducted with Japanese family caregivers of home-dwelling persons with dementia in June 2021. Family caregivers evaluated the level of depressive symptoms in persons with dementia using the Neuropsychiatric Inventory (NPI). Caregivers also rated the quality of life of persons with dementia using the EQ-5D-5L. Results: A total of 379 family caregivers participated in the survey. Depressive symptoms were reported in 143 persons with dementia (37.7%). A total of 155 persons with dementia (40.9%) had initiated ACP, of which 88 (56.8%) had care professionals involved in ACP conversation. After adjusting for the characteristics of persons with dementia and caregivers, persons with professional involvement showed significantly more severe depressive symptoms compared to those who did not initiate ACP. There was no significant difference in the quality of life of persons with dementia according to ACP initiation. Conclusions: Many home-dwelling persons with dementia experienced depressive symptoms during the COVID-19 pandemic, especially in cases where care professionals were involved in ACP conversations. Optimal and proactive ACP approaches need to be developed to prevent depressive symptoms in newly diagnosed persons.

Depression and Anxiety in Older Adults with Dementia During the COVID-19 Pandemic.

This study examined the longitudinal association between dementia, activity participation, the coronavirus disease 2019 pandemic period, and 1-year mental health changes. We obtained data from the National Health and Aging Trends Study in the United States. We included 4,548 older adult participants of two or more survey rounds between 2018 and 2021. We identified baseline dementia status, and assessed depressive symptoms and anxiety at baseline and follow-up. Dementia and poor activity participation were independently associated with an increased prevalence of depressive symptoms and anxiety. Dementia care and support should address emotional and social needs under continued public health restrictions.

Microarray dataset of gene transcription in mouse microglia and peripheral monocytes in contextual fear conditioning.

The transcription profile of microglia related to fear conditioning remains unclear. Here, we used Illumina MouseWG-6v2 microarrays to investigate the gene transcription changes in microglia and peripheral monocytes after contextual fear conditioning of C57BL/6 J mice. Mice were trained with or without a single minimized footshock stimulation (0-s or 2-s, 0.4 mA) and re-exposed to the training context without footshock for three different durations 24 h later: 0 min (FS0), 3 min (FS3), or 30 min (FS30). Whole brain microglia and peripheral monocytes were prepared 24 h after re-exposure using a neural tissue dissociation kit, including non-footshock controls for two re-exposure durations (Con3 and Con30). The data can be valuable for researchers interested in glial cells and neurotransmission studies and are related to the research article "Contextual fear conditioning regulates synapse-related gene transcription in mouse microglia".

Sex-Specific Differences in the Transcriptome of the Human Dorsolateral Prefrontal Cortex in Schizophrenia.

Schizophrenia presents clinical and biological differences between males and females. This study investigated transcriptional profiles in the dorsolateral prefrontal cortex (DLPFC) using postmortem data from the largest RNA-sequencing (RNA-seq) database on schizophrenic cases and controls. Data for 154 male and 113 female controls and 160 male and 93 female schizophrenic cases were obtained from the CommonMind Consortium. In the RNA-seq database, the principal component analysis showed that sex effects were small in schizophrenia. After we analyzed the impact of sex-specific differences on gene expression, the female group showed more significantly changed genes compared with the male group. Based on the gene ontology analysis, the female sex-specific genes that changed were overrepresented in the mitochondrion, ATP (phosphocreatine and adenosine triphosphate)-, and metal ion-binding relevant biological processes. An ingenuity pathway analysis revealed that the differentially expressed genes related to schizophrenia in the female group were involved in midbrain dopaminergic and γ-aminobutyric acid (GABA)-ergic neurons and microglia. We used methylated DNA-binding domain-sequencing analyses and microarray to investigate the DNA methylation that potentially impacts the sex differences in gene transcription using a maternal immune activation (MIA) murine model. Among the sex-specific positional genes related to schizophrenia in the PFC of female offspring from MIA, the changes in the methylation and transcriptional expression of loci ACSBG1 were validated in the females with schizophrenia in independent postmortem samples by real-time PCR and pyrosequencing. Our results reveal potential genetic risks in the DLPFC for the sex-dependent prevalence and symptomology of schizophrenia.

Arachidonic acid and cancer risk: a systematic review of observational studies.

BACKGROUND: An n-6 essential fatty acid, arachidonic acid (ARA) is converted into prostaglandin E2, which is involved in tumour extension. However, it is unclear whether dietary ARA intake leads to cancer in humans. We thus systematically evaluated available observational studies on the relationship between ARA exposure and the risk of colorectal, skin, breast, prostate, lung, and stomach cancers. METHODS: We searched the PubMed database for articles published up to May 17, 2010. 126 potentially relevant articles from the initial search and 49,670 bibliographies were scrutinised to identify eligible publications by using predefined inclusion criteria. A comprehensive literature search yielded 52 eligible articles, and their reporting quality and methodological quality was assessed. Information on the strength of the association between ARA exposure and cancer risk, the dose-response relationship, and methodological limitations was collected and evaluated with respect to consistency and study design. RESULTS: For colorectal, skin, breast, and prostate cancer, 17, 3, 18, and 16 studies, respectively, were identified. We could not obtain eligible reports for lung and stomach cancer. Studies used cohort (n = 4), nested case-control (n = 12), case-control (n = 26), and cross-sectional (n = 12) designs. The number of subjects (n = 15 - 88,795), ARA exposure assessment method (dietary intake or biomarker), cancer diagnosis and patient recruitment procedure (histological diagnosis, cancer registries, or self-reported information) varied among studies. The relationship between ARA exposure and colorectal cancer was inconsistent based on ARA exposure assessment methodology (dietary intake or biomarker). Conversely, there was no strong positive association or dose-response relationship for breast or prostate cancer. There were limited numbers of studies on skin cancer to draw any conclusions from the results. CONCLUSIONS: The available epidemiologic evidence is weak because of the limited number of studies and their methodological limitations, but nonetheless, the results suggest that ARA exposure is not associated with increased breast and prostate cancer risk. Further evidence from well-designed observational studies is required to confirm or refute the association between ARA exposure and risk of cancer.

Differential diagnosis of lipoma and atypical lipomatous tumor/well-differentiated liposarcoma by cytological analysis.

BACKGROUND: Adipocytic tumors are the most common soft tissue tumors, with lipomas and atypical lipomatous tumor/well-differentiated liposarcomas (ALT/WDL), which comprise most cases. Preoperative differential diagnosis of lipoma or ALT/WDL can provide important information for decisions regarding treatment. We evaluated the cytological findings of 20 cases of lipoma and ALT/WDL. METHODS: Fluorescence in situ hybridization (FISH) was performed on formalin-fixed paraffin-embedded specimens (FFPE) to examine mouse double minute 2 homolog (MDM2) amplification in all cases. Tissue samples were collected from the center of the surgical materials, stained with Pap, and evaluated for 12 cytological parameters by six cytotechnologists. RESULTS: The findings regarding large atypical cells, multinucleated cells, and nuclear pleomorphism were highly concordant among the cytotechnologists and were associated with MDM2 amplification. Large atypical cells, considered a highly specific feature of ALT/WDL, were not observed in lipoma cases. However, the sensitivity of the large atypical cell findings was not high (67%); therefore, comprehensive evaluation of multinucleated cells and pleomorphism is crucial for predicting ALT/WDL diagnosis. FISH of MDM2 on Pap-stained specimens was performed in four cases. In two, the results were similar to those of MDM2 FISH performed on FFPE sections and were reproducible, whereas in the other two, the signal could not be evaluated because of the strong background coloration. CONCLUSIONS: Cytology specimens may be useful for the preoperative diagnosis of adipocytic tumors, particularly if the FISH conditions for Pap-stained specimens and the detection accuracy of MDM2 amplification can be improved.