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BACKGROUND: Nectins are cell adhesion molecules that play a pivotal role in adherens junctions and tight junctions. Our previous study using whole-genome oligonucleotide microarrays revealed that nectin-4 was upregulated in pre-eclamptic placentas. We investigated the role of nectin-4 in the etiology of pre-eclampsia. METHODS: We investigated the expression of nectin-4 using real-time RT-PCR, western blot and immunostaining. Additionally, we performed matrigel invasion assay and cytotoxicity assay using cells overexpressing the nectin-4. RESULTS: NECTIN4 transcripts were elevated in pre-eclamptic placentas relative to uncomplicated pregnancies. Nectin-4 protein levels in pre-eclamptic placentas were higher on a semi-quantitative western blot. Nectin-4 was localized at the apical cell membrane in syncytiotrophoblast cells and not at the adherens junctions. Nectin-4 was also detected in cytotrophoblasts and a subset of cells in the decidua. Nectin-4 overexpressing trophoblast cells migrated normally in the matrix. However, Natural killer (NK) cells showed a strong cytotoxic effect against nectin-4 overexpressing trophoblast cells. No causative genetic variation was evident in the NECTIN4 gene from a pre-eclamptic placenta. CONCLUSIONS: There are as yet unknown factors that induce nectin-4 overexpression in trophoblast cells that may contribute to abnormal placentation via an aberrant immune response and the onset of a pre-eclamptic pregnancy.
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Moléculas de Adesão Celular/genética , Decídua/imunologia , Pré-Eclâmpsia/genética , RNA Mensageiro/genética , Trofoblastos/imunologia , Adulto , Estudos de Casos e Controles , Moléculas de Adesão Celular/imunologia , Cesárea , Citotoxicidade Imunológica , Decídua/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Imunidade Inata , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Pré-Eclâmpsia/imunologia , Pré-Eclâmpsia/patologia , Pré-Eclâmpsia/cirurgia , Gravidez , RNA Mensageiro/imunologia , Trofoblastos/patologiaRESUMO
Although embryo screening by preimplantation genetic diagnosis (PGD) has become the standard technique for the treatment of recurrent pregnancy loss in couples with a balanced gross chromosomal rearrangement, the implantation and pregnancy rates of PGD using conventional fluorescence in situ hybridization (FISH) remain suboptimal. Comprehensive molecular testing, such as array comparative genomic hybridization and next-generation sequencing, can improve these rates, but amplification bias in the whole genome amplification method remains an obstacle to accurate diagnosis. Recent advances in amplification procedures combined with improvements in the microarray platform and analytical method have overcome the amplification bias, and the data accuracy of the comprehensive PGD method has reached the level of clinical laboratory testing. Currently, comprehensive PGD is also applied to recurrent pregnancy loss due to recurrent fetal aneuploidy or infertility with recurrent implantation failure, known as preimplantation genetic screening. However, there are still numerous problems to be solved, including misdiagnosis due to somatic mosaicism, cell cycle-related background noise, and difficulty in diagnosis of polyploidy. The technology for comprehensive PGD also requires further improvement.
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BACKGROUND: In the present study, we report on a couple who underwent prenatal genetic diagnosis for autosomal recessive polycystic kidney disease (ARPKD). CASE PRESENTATION: This healthy couple had previously had a healthy boy but had experienced two consecutive neonatal deaths due to respiratory distress resulting from pulmonary hypoplasia caused by oligohydramnios. The woman consulted our facility after she realized she was pregnant again. We promptly performed a carrier test for the PKHD1 gene by target exome sequencing of samples from the couple. A pathogenic mutation was identified only in the paternal allele (c.9008C>T, p.S3003F). The mutation was confirmed by Sanger sequencing of the DNA from formalin-fixed, paraffin-embedded, kidney tissue of the second neonate patient and was not found in the healthy sibling. We then performed haplotype analyses using microsatellite markers scattered throughout the PKHD1 gene. DNA from the amniocentesis was determined to belong to a carrier, and the couple decided to continue with the pregnancy, obtaining a healthy newborn. Subsequent detailed examination of the exome data suggested higher read depth at exons 45 and 46. Multiplex ligation-dependent probe amplification allowed identification of duplication of these two exons. This case suggests the potential usefulness of target exome sequencing in the prenatal diagnosis of the PKHD1 gene in ARPKD. CONCLUSIONS: This is the first report of intragenic duplication in the PKHD1 gene in ARPKD.
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Mutação , Rim Policístico Autossômico Recessivo/diagnóstico , Rim Policístico Autossômico Recessivo/genética , Receptores de Superfície Celular/genética , Amniocentese/métodos , Exoma , Feminino , Humanos , Masculino , Gravidez , Análise de Sequência de DNA , Adulto JovemRESUMO
INTRODUCTION: The da Vinci SP surgical system is a surgical platform capable of implementing robotic-assisted surgery through a single port and was first introduced in Japan at our hospital. In this paper, we describe our experience of the initial introduction of the da Vinci SP surgical system and its surgical outcomes. This is the first report on the surgical outcomes of using da Vinci SP, and its comparison with the conventional system in Japan. METHODS: After developing an application for a highly difficult new medical technology in-house, we compared the surgical outcomes (median values) of 15 patients who had undergone total hysterectomy at our hospital using the da Vinci SP (1-port) system (SP group) for uterine myoma after March 2023 and of 154 patients who underwent total hysterectomy using the conventional da Vinci Xi (four ports) system (Xi group) for uteri weighing <500 g. RESULTS: The results of the comparison of the characteristics between 15 patients in the SP group and 154 patients in the Xi group were as follows: uterus weight (g): 230 (90-500) versus 222 (55-496) (p = .35); surgical time (minutes): 199 (171-251) versus 198 (88-387) (p = .63); intraoperative blood loss (mL): 13 (5-82) versus 20 (2-384) (p = .17); and rate of surgical complication (%): 0.0 versus 1.3 (p = .66). The data indicated a comparable weight of the resected uterus, surgical time, intraoperative blood loss, and rate of surgical complications between the two groups. CONCLUSION: Robotic-assisted total hysterectomy using the da Vinci SP surgical system allowed clinicians to safely perform surgeries according to the conventional systems.
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Leiomioma , Procedimentos Cirúrgicos Robóticos , Feminino , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Perda Sanguínea Cirúrgica , Histerectomia , Resultado do Tratamento , Estudos RetrospectivosRESUMO
Objectives: Most cases of caffeine intoxication result from the excessive intake of over-the-counter drugs and energy drinks. However, few cases of caffeine intoxication due to the excessive consumption of bottled coffee products have been reported. Herein, we present a case report of caffeine intoxication. Patient: A 39-year-old man experienced numbness and weakness in the extremities for three nights over five days. Results: Blood tests revealed hypophosphatemia and low 25-OH vitamin D concentration. The symptoms disappeared the next day without any additional treatment. A lifestyle interview revealed that he regularly consumed bottled coffee like it was water and had approximately 1 L of it from evening to night. He was diagnosed with weakness in the extremities due to hypophosphatemia caused by caffeine intoxication. Upon investigating some bottled coffee products, we found that only a few of them had labels disclosing caffeine content and warnings of the risks of excessive caffeine intake. Conclusion: We encountered a case of caffeine intoxication via coffee. Although rare in the past, caffeine intoxication might increase owing to the widespread use of bottled coffee products. The caffeine content of coffee products should be indicated on labels to warn consumers.
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Objectives: Nectin-4 is a cell adhesion molecule with vital functions at adherens and tight junctions. Cumulative evidence now indicates that the NECTIN4 gene is overexpressed in a variety of cancers, and that the nectin-4 protein is both a disease marker and therapeutic target in a subset of these cancers. We previously demonstrated that NECTIN4 is overexpressed in placenta during pre-eclamptic pregnancy, which is one of the most serious obstetric disorders. Methods: Nectin-4 protein levels were measured in maternal sera from pregnant women with pre-eclampsia and its related disorder, unexplained fetal growth retardation. Results: Maternal serum concentrations of nectin-4 were significantly elevated in pre-eclamptic women compared with those with an uncomplicated normotensive pregnancy. However, no increase was observed in pregnancies with unexplained fetal growth retardation. Serum nectin-4 levels were higher in cases with early-onset pre-eclampsia that generally showed more severe clinical symptoms, but levels were not correlated to other clinical indicators of disease severity. Conclusions: Nectin-4 is a potential new diagnostic and predictive biomarker for severe pre-eclampsia.
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BACKGROUND: FLT1 is one of the significantly overexpressed genes found in a pre-eclamptic placenta and is involved with the etiology of this disease. METHODS: We conducted genome-wide expression profiling by RNA-seq of placentas from women with pre-eclampsia and those with normotensive pregnancy. RESULTS: We identified a lncRNA gene, MG828507, located ~80 kb upstream of the FLT1 gene in a head-to-head orientation, which was overexpressed in the pre-eclamptic placenta. MG828507 and FLT1 are located within the same topologically associated domain in the genome. The MG828507 mRNA level correlated with that of the FLT1 in placentas from pre-eclamptic women as well as in samples from uncomplicated pregnancies. However, neither the overexpression nor knockdown of MG828507 affected the expression of FLT1. Analysis of pre-eclampsia-linking genetic variants at this locus suggested that the placental genotype of one variant was associated with the expression of MG828507. The MG828507 transcript level was not found to be associated with maternal blood pressure, but showed a relationship with birth and placental weights, suggesting that this lncRNA might be one of the pivotal placental factors in pre-eclampsia. CONCLUSION: Further characterization of the MG828507 gene may elucidate the etiological roles of the MG828507 and FLT1 genes in pre-eclampsia in a genomic context.
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Pertuzumab, a humanized antibody drug, has improved outcomes of patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer, when administered in combination with trastuzumab and other chemotherapies. Cardiotoxicity due to trastuzumab is widely recognized, while data on pertuzumab-based treatments in daily clinical practice are lacking. We herein report 2 Japanese patients, aged 72 and 49 years, who developed left ventricular dysfunction after pertuzumab administration, following long-term trastuzumab treatments. Both patients underwent curative surgery for their HER2-positive breast cancer and received anthracycline-based treatments. After developing metastatic disease, trastuzumab-based treatments were administered without cardiac toxicity, but both patients developed left ventricular dysfunction after pertuzumab administration (6 and 13 cycles, respectively). Although several large randomized trials have shown no additive effect of pertuzumab on cardiac dysfunction, careful monitoring of cardiac function appears to be necessary in daily practice, particularly for patients with prior long-term trastuzumab treatments.
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BACKGROUND: Metastatic breast cancer (MBC) is generally considered to be incurable. Although many options are available for treating MBC, physicians often encounter difficulties in choosing the most appropriate treatment because the MBCs of individual patients respond differently even to the same treatments. Thus, predictive markers for therapeutic efficacy are urgently needed. Neutrophil- and platelet-to-lymphocyte ratios (NLR and PLR, respectively), have been studied and established as prognostic markers for breast cancer patients but whether either or both of these markers are predictive of treatment responses is still unclear. Herein, we investigated predictive markers for eribulin-based treatment responsiveness in patients with MBC, by examining clinicopathological features, including several markers of immunocompetent cells in peripheral blood. METHODS: Clinicopathological features of the 104 patients with metastatic/Stage IV breast cancer given eribulin-based regimens were investigated in relation to clinical responses to eribulin-based treatments and progression-free-survival (PFS). RESULTS: Special histological types and high NLR at baseline were independently related to poor clinical responses to the treatments (p = 0.023 and 0.039, respectively). The Cox hazard model revealed that patients with oestrogen receptor (ER)-negative tumours and high NLR, monocyte-to-lymphocyte ratio (MLR) and PLR showed significantly shorter PFS (p = 0.021, 0.005, 0.008 and 0.030, respectively). On multivariate analysis, only ER status and NLR remained independent factors related to PFS (p = 0.011 and 0.003, respectively). CONCLUSIONS: Our data revealed that special histological types and high NLR might be factors related to low responsiveness to eribulin-based regimens in patients with MBC.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Furanos/uso terapêutico , Cetonas/uso terapêutico , Linfócitos/imunologia , Neutrófilos/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/sangue , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Feminino , Humanos , Contagem de Linfócitos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Contagem de Plaquetas , Prognóstico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Several clinical studies have examined circulating tumour cells (CTCs). However, the application of CTCs as a predictive/prognostic marker for breast cancer patients has yet to be established, particularly the selection of suitable markers for detecting CTCs. We recently investigated CTCs, including mesenchymal status, from metastatic breast cancer patients who had received eribulin-based treatment. We found that assessment of both mesenchymal and epithelial CTCs might be important for predicting eribulin responsiveness. In the current study, we followed up the outcomes of these patients after eribulin treatment and investigated the possibility of CTC analysis results serving as prognostic markers for this patient population. Twenty-one patients were enrolled and peripheral blood samples were collected before eribulin-based treatments. CTCs were then examined using a Microfluidic Chip device. CTCs positive for vimentin and pan-cytokeratin were defined as mesenchymal and epithelial CTCs, respectively. Overall survival (OS) was assessed in relation to the number of CTCs and clinicopathological factors. During the observation period, 13 patients (62%) died due to breast cancer and the median OS was 18 months. Patients with high-grade tumours and a high total number of CTCs showed significantly shorter OS than those with low-grade tumours and smaller CTC burdens (p = 0.026 and 0.037, respectively). Patients who received eribulin as the first chemotherapy for metastatic disease showed longer OS (p = 0.006). Our data suggest that determining numbers of both mesenchymal and epithelial CTCs might predict survival for patients receiving eribulin.
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Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Furanos/uso terapêutico , Cetonas/uso terapêutico , Células Neoplásicas Circulantes/patologia , Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/mortalidade , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Vimentina/uso terapêuticoRESUMO
Examination of maternal plasma cell-free DNA (cfDNA) for noninvasive prenatal testing for fetal trisomy is a highly effective method for pregnant women at high risk. This can be also applied to fetal gender determination in female carriers of severe X-linked disease. Polymerase chain reaction (PCR) analysis is a relatively simpler and less expensive method of detecting Y chromosome-specific repeats (Y-specific PCR; YSP), but is limited by the risk of false-negative results. To address this, we have developed a combined strategy incorporating YSP and an estimation of the fetal DNA fraction. Multiplex PCR for 30 single nucleotide polymorphism (SNP) loci selected by high heterozygosity enables the robust detection of the fetal DNA fraction in cfDNA. The cfDNA sample is first subjected to YSP. When the YSP result is positive, the fetus is male and invasive testing for an X-linked mutation is then required. When the YSP result is negative, the cfDNA sample is analyzed using multiplex PCR. If fetal DNA is then found in the cfDNA, invasive testing is not then required. If the multiplex PCR analysis of cfDNA is negative for fetal DNA, the fetal gender cannot be determined and invasive testing is still required. Our technique provides a potentially effective procedure that can help to avoid unnecessary invasive prenatal testing in some female carriers of severe X-linked disease.
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Ácidos Nucleicos Livres/genética , Cromossomos Humanos X/química , Cromossomos Humanos Y/química , Síndrome de Down/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Diagnóstico Pré-Natal/métodos , Adulto , Biomarcadores/sangue , Ácidos Nucleicos Livres/sangue , Síndrome de Down/sangue , Síndrome de Down/genética , Feminino , Feto , Doenças Genéticas Ligadas ao Cromossomo X/sangue , Heterozigoto , Humanos , Masculino , Repetições de Microssatélites , Reação em Cadeia da Polimerase Multiplex/métodos , Polimorfismo de Nucleotídeo Único , Gravidez , Primeiro Trimestre da Gravidez , TrissomiaRESUMO
OBJECTIVES: Venous thromboembolism (VTE) is often a problematic complication in patients with gynecological cancer. Despite increasing opportunities to use direct oral anticoagulants (DOACs) to treat VTE, there are no reports on the therapeutic outcomes of DOACs in patients with gynecological cancer; however, there are some studies on cancer patients in general. We retrospectively examined the efficacy and safety of using DOACs to treat VTE in such patients. METHODS: The study cohort comprised 43 patients with gynecological cancer and VTE who received treatment between May 2005 and April 2016. They were divided into two groups: DOACs used (DOAC group, n=21) and only unfractionated heparin (UFH) and warfarin used (standard group, n=22). The rates of improvement and recurrence of VTE and incidence of adverse events were compared between these groups. RESULTS: At 6 months, the VTE of 85% of patients in the DOAC group and of 75% in the standard group had improved (p=0.59). No recurrences of VTE occurred in the DOAC group; where VTE recurred in 12.5% of patients in the standard group. Adverse events occurred in three patients in the DOAC group (15.3%) and one in the standard group (7.7%). Chemotherapy significantly impacted improvement in VTE (p=0.01). CONCLUSIONS: Rates of VTE improvement and of recurrence of VTE and adverse events did not differ significantly between the study groups.
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Thanatophoric dysplasia and achondroplasia are allelic disorders caused by a constitutively active mutation in the FGFR3 gene. Because thanatophoric dysplasia is a lethal disorder and achondroplasia is non-lethal, they need to be distinguished after ultrasound identification of fetal growth retardation with short limbs. Accordingly, we have developed a noninvasive prenatal test using cell-free fetal DNA in the maternal circulation to distinguish thanatophoric dysplasia and achondroplasia. A multiplex PCR system encompassing five mutation hotspots in the FGFR3 gene allowed us to efficiently identify the responsible mutation in cell-free DNA in all examined pregnancies with a suspected thanatophoric dysplasia or achondroplasia fetus. This system will be helpful in the differential diagnosis of thanatophoric dysplasia and achondroplasia in early gestation and in couples concerned about the recurrence of thanatophoric dysplasia due to germinal mosaicism.
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Acondroplasia/genética , Ácidos Nucleicos Livres/genética , Retardo do Crescimento Fetal/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Diagnóstico Pré-Natal/métodos , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Displasia Tanatofórica/genética , Acondroplasia/sangue , Acondroplasia/diagnóstico por imagem , Acondroplasia/patologia , Adulto , Sequência de Bases , Biomarcadores/sangue , Ácidos Nucleicos Livres/sangue , Diagnóstico Diferencial , Feminino , Retardo do Crescimento Fetal/sangue , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/patologia , Feto , Expressão Gênica , Humanos , Mosaicismo , Mutação , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/sangue , Displasia Tanatofórica/sangue , Displasia Tanatofórica/diagnóstico por imagem , Displasia Tanatofórica/patologia , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
Metastatic breast cancer cannot be curable, but significant improvement in overall survival has been observed with the appearance of new agents. The purpose of treatment is to prolong survival and to improve quality of life by reducing cancer-related symptoms. To achieve these goals, individualized approach is required. Chemotherapy is used for patients with hormone receptor negative breast cancer or hormone receptor positive patients who have cancer-related symptoms. The choice of regimen (single-agent or a combination), selection of a specific therapy and the duration of treatment depend on multiple factors, including the tumor burden, general health status, prior treatments and toxicities, and patient preferences.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Oncologia/tendências , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Humanos , Metástase Neoplásica , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismoRESUMO
Adenoid cystic carcinoma (AdCC), one of the most common salivary gland carcinomas, usually has a fatal outcome. Epidermal growth factor receptor (EGFR) pathway gene mutations are important in predicting a patient's prognosis and estimating the efficacy of molecular therapy targeting the EGFR pathway. In this study of salivary gland AdCC (SAdCC), we looked for gene mutations in EGFR, RAS family (KRAS, HRAS, and NRAS), PIK3CA, BRAF, and AKT1, using a highly sensitive single-base extension multiplex assay, SNaPshot. Out of 70 cases, EGFR pathway missense mutations were found in 13 (18.6%): RAS mutations in 10 (14.3%), EGFR in one (1.4%), and PIK3CA in 5 (7.1%). None of the cases showed an EGFR deletion by direct sequencing. Concurrent gene mutations were found in three cases (4.3%). EGFR pathway mutations were significantly associated with a shorter disease-free (p = 0.011) and overall survival (p = 0.049) and RAS mutations were as well; (p = 0.010) and (p = 0.024), respectively. The gene fusion status as determined by a FISH assay had no significant association with mutations of the genes involved in the EGFR pathway. In conclusion, EGFR pathway mutations, especially RAS mutations, may be frequent in SAdCC, and associated with a poor prognosis for the patient.
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Atrial natriuretic peptide is biologically activated by the atrial natriuretic peptide-converting enzyme, corin, and has an important role in regulating blood pressure. We detected elevated serum corin levels in women with pre-eclampsia. Interestingly, the serum corin levels were also found to be elevated in pregnancies with a related disorder, unexplained fetal growth restriction (FGR) without hypertension, suggesting that this phenomenon is not simply a response to maternal hypertension. CORIN mRNA levels were not elevated in placentas from pre-eclampsia or unexplained FGR cases. Likewise, similar signal intensities were found for corin in placental syncytiotrophoblast cells by immunostaining. In contrast, corin signals were higher in maternal decidua cells from pre-eclampsia and unexplained FGR cases. These data suggest that corin may be upregulated in maternal decidua in response to an etiologic pathway that is common to pre-eclampsia and FGR.
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Retardo do Crescimento Fetal/sangue , Pré-Eclâmpsia/sangue , Serina Endopeptidases/sangue , Adulto , Decídua/metabolismo , Feminino , Retardo do Crescimento Fetal/metabolismo , Humanos , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Gravidez , Serina Endopeptidases/metabolismo , Trofoblastos/metabolismoRESUMO
BACKGROUND: As data on using MammaPrint®, a 70-gene expression profile for molecular subtyping of breast cancer, are limited in Japanese patients, we aimed to determine the gene profiles of Japanese patients using MammaPrint and to investigate its possible clinical application for selecting adjuvant treatments. PATIENTS AND METHODS: 50 women treated surgically at our institution were examined. The MammaPrint results were compared with the St Gallen 2007 and intrinsic subtype risk categorizations. RESULTS: Of 38 cases judged to be at intermediate risk based on the St Gallen 2007 Consensus, 11 (29%) were in the high-risk group based on MammaPrint. 1 of the 30 luminal A-like tumors (3%) was judged as high risk based on MammaPrint results, whereas 7 of the 20 tumors (35%) categorized as luminal B-like or triple negative were in the low-risk group. There have been no recurrences to date in the MammaPrint group, and this is possibly attributable to most of the high-risk patients receiving chemotherapy that had been recommended on the basis of their MammaPrint results. CONCLUSIONS: Our results indicate that MammaPrint is applicable to Japanese patients and that it is of potential value in current clinical practice for devising individualized treatments.
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Aneuploidy in fetal chromosomes is one of the causes of pregnancy loss and of congenital birth defects. It is known that the frequency of oocyte aneuploidy increases with the human maternal age. Recent data have highlighted the contribution of cohesin complexes in the correct segregation of meiotic chromosomes. In mammalian oocytes, cohesion is established during the fetal stages and meiosis-specific cohesin subunits are not replenished after birth, raising the possibility that the long meiotic arrest of oocytes facilitates a deterioration of cohesion that leads to age-related increases in aneuploidy. We here examined the cohesin levels in dictyate oocytes from different age groups of humans and mice by immunofluorescence analyses of ovarian sections. The meiosis-specific cohesin subunits, REC8 and SMC1B, were found to be decreased in women aged 40 and over compared with those aged around 20 years (P<0.01). Age-related decreases in meiotic cohesins were also evident in mice. Interestingly, SMC1A, the mitotic counterpart of SMC1B, was substantially detectable in human oocytes, but little expressed in mice. Further, the amount of mitotic cohesins of mice slightly increased with age. These results suggest that, mitotic and meiotic cohesins may operate in a coordinated way to maintain cohesions over a sustained period in humans and that age-related decreases in meiotic cohesin subunits impair sister chromatid cohesion leading to increased segregation errors.