Background

Detachment of plant organs occurs in abscission zones (AZs). During plant growth, the AZ forms, but does not develop further until the cells perceive abscission-promoting signals and initiate detachment. Upon signal perception, abscission initiates immediately; if there is no signal, abscission is not induced and the organ remains attached to the plant. However, little attention has been paid to the genes that maintain competence to respond to the abscission signal in the pre-abscission AZ. Recently, we found that the tomato (Solanum lycopersicum) transcription factors BLIND (Bl), GOBLET (GOB), Lateral suppressor (Ls) and a tomato WUSCHEL homologue (LeWUS) are expressed specifically in pre-abscission tissue, the anthesis pedicel AZs. To advance our understanding of abscission, here we profiled genome-wide gene expression in tomato flower pedicels at the pre-abscission stage.

Results

We examined the transcriptomes of three tomato flower pedicel regions, the AZ and flanking proximal- (Prox) and distal- (Dis) regions, and identified 89 genes that were preferentially expressed in the AZ compared to both Prox and Dis. These genes included several transcription factors that regulate apical or axillary shoot meristem activity. Also, genes associated with auxin activity were regulated in a Prox-Dis region-specific manner, suggesting that a gradient of auxin exists in the pedicel. A MADS-box gene affecting floral transition was preferentially expressed in the Prox region and other MADS-box genes for floral organ identification were preferentially expressed in Dis, implying that the morphologically similar Prox and Dis regions have distinct identities. We also analyzed the expression of known regulators; in anthesis pedicels, Bl, GOB, Ls and LeWUS were expressed in the vascular cells of the AZ region. However, after an abscission signal, Bl was up-regulated, but GOB, Ls and LeWUS were down-regulated, suggesting that Bl may be a positive regulator of abscission, but the others may be negative regulators.

Conclusions

This study reveals region-specific gene expression in tomato flower pedicels at anthesis and identifies factors that may determine the physiological properties of the pre-abscission pedicel. The region-specific transcriptional regulators and genes for auxin activity identified here may prevent flower abscission in the absence of signal or establish competence to respond to the abscission signal.

Purpose

The purpose of this study was to evaluate whether neo-adjuvant hormonal therapy (NHT) prior to radical retropubic prostatectomy (RRP) for prostate cancer (PCa) is beneficial in terms of surgical outcomes and for preventing or delaying biochemical recurrence via single-surgeon case series study.

Materials and Methods

Fifty-three men underwent RRP by a single surgeon. The patients were divided into two groups according to whether or not NHT was performed prior to RRP. The study was analyzed retrospectively. We evaluated clinical parameters, surgical parameters, and biochemical recurrence rate. Group 1 (n=34) was treated with RRP only, while Group 2 (n=19) underwent RRP along with NHT.

Results

There were no significant differences in clinical, operation-related and pathological factors between the two groups (p>0.05). There was also no significant difference in biochemical recurrence rate between the two groups at the last follow-up, although Group 2 tended to have a lower PCa recurrence rate than Group 1 and the initial prostate-specific antigen (PSA) level was significantly higher in Group 2 than Group 1 (p=0.0496).

Conclusion

The present single-surgeon case series study revealed a trend toward a lower rate of PCa recurrence in NHT+RRP treated patients compared to those treated with RRP alone, but this did not reach statistical significance, despite the fact that NHT+RRP patients exhibited higher serum PSA levels preoperatively. Prospective studies with a longer duration of observation and a greater number of patients would be helpful in evaluating NHT more definitively.

Background

Psychiatry has been consistently shown to be a profession characterised by ‘high-burnout’; however, no nationwide surveys on this topic have been conducted in Japan.

Aims

The objective of this study was to estimate the prevalence of burnout and to ascertain the relationship between work environment satisfaction, work-life balance satisfaction and burnout among psychiatrists working in medical schools in Japan.

Method

We mailed anonymous questionnaires to all 80 psychiatry departments in medical schools throughout Japan. Work-life satisfaction, work-environment satisfaction and social support assessments, as well as the Maslach Burnout Inventory (MBI), were used.

Results

Sixty psychiatric departments (75.0%) responded, and 704 psychiatrists provided answers to the assessments and MBI. Half of the respondents (n = 311, 46.0%) experienced difficulty with their work-life balance. Based on the responses to the MBI, 21.0% of the respondents had a high level of emotional exhaustion, 12.0% had a high level of depersonalisation, and 72.0% had a low level of personal accomplishment. Receiving little support, experiencing difficulty with work-life balance, and having less work-environment satisfaction were significantly associated with higher emotional exhaustion. A higher number of nights worked per month was significantly associated with higher depersonalisation.

Conclusions

A low level of personal accomplishment was quite prevalent among Japanese psychiatrists compared with the results of previous studies. Poor work-life balance was related to burnout, and social support was noted to mitigate the impact of burnout.

An epidermal cyst is a common benign subcutaneous tumor and rarely develops malignancy. We report a case of an undifferentiated cutaneous squamous cell carcinoma (SCC) that arose from an epidermal cyst on the left side of the neck. The epidermal cyst had rapidly increased in size and presented cauliflower-like tumor. Histological study revealed undifferentiated squamous cell carcinoma that was arising from the epidermal cyst.

Background

Idiopathic pleuroparenchymal fibroelastosis (IPPFE) is a recently reported group of disorders characterized by fibrotic thickening of the pleural and subpleural parenchyma predominantly in the upper lobes. We report five Japanese cases fulfilling the criteria of IPPFE and address whether it should be considered a separate clinicopathologic entity. And this study was an attempt to identify features in common between IPPFE and previously described idiopathic upper lobe fibrosis (IPUF), allowing IPPFE to be considered as a distinct entity in our Japanese series.

Methods

Five consecutive cases of idiopathic interstitial lung disease confirmed as IPPFE by surgical lung biopsy were studied.

Results

There were four males and one female, aged 70±2.76 yr. No associated disorder or presumed cause was found in any case. Lung function tests found a restrictive ventilatory defect (4/5) and/or impairment of DLco (4/5). Chest X-ray showed marked apical pleural thickening in all cases. Computed tomography of the chest in all cases mainly showed intense pleural thickening and volume loss associated with evidence of fibrosis, predominantly in the upper lobes. In all cases in this study, markedly thickened visceral pleura and prominent subpleural fibrosis characterized by both elastic tissue and dense collagen were clearly shown. All cases were alive at the last follow-up, 17.6±13.59 months after diagnosis; however, all had deteriorated both clinically and radiologically.

Conclusions

IPPFE deserves to be defined as a separate, original clinicopathologic entity owing to its uniformity and IPPFE has some features in common with previously described idiopathic upper lobe fibrosis (IPUF). Our limited experience with a cohort of 5 subjects suggests that IPPFE can be rapidly progressive.

H2DB (http://tga.nig.ac.jp/h2db/), an annotation database of genetic heritability estimates for humans and other species, has been developed as a knowledge database to connect trait-associated genomic loci. Heritability estimates have been investigated for individual species, particularly in human twin studies and plant/animal breeding studies. However, there appears to be no comprehensive heritability database for both humans and other species. Here, we introduce an annotation database for genetic heritabilities of various species that was annotated by manually curating online public resources in PUBMED abstracts and journal contents. The proposed heritability database contains attribute information for trait descriptions, experimental conditions, trait-associated genomic loci and broad- and narrow-sense heritability specifications. Annotated trait-associated genomic loci, for which most are single-nucleotide polymorphisms derived from genome-wide association studies, may be valuable resources for experimental scientists. In addition, we assigned phenotype ontologies to the annotated traits for the purposes of discussing heritability distributions based on phenotypic classifications.

Cell-type-specific expression of optogenetic molecules allows temporally precise manipulation of targeted neuronal activity. Here we present a toolbox of 4 knock-in mouse lines engineered for strong, Cre-dependent expression of channelrhodopsins ChR2-tdTomato and ChR2-EYFP, halorhodopsin eNpHR3.0, and archaerhodopsin Arch-ER2. All 4 transgenes mediate Cre-dependent, robust activation or silencing of cortical pyramidal neurons in vitro and in vivo upon light stimulation, with ChR2-EYFP and Arch-ER2 demonstrating light sensitivity approaching that of in utero or virally transduced neurons. We further show specific photoactivation of parvalbumin-positive interneurons in behaving ChR2-EYFP reporter mice. The robust, consistent, and inducible nature of our ChR2 mice represents a significant advancement over previous lines, whereas the Arch-ER2 and eNpHR3.0 mice are the first demonstration of successful conditional transgenic optogenetic silencing. When combined with the hundreds of available Cre-driver lines, this optimized toolbox of reporter mice will enable widespread investigations of neural circuit function with unprecedented reliability and accuracy.

Expression of ADAM12 is low in most normal tissues, but is markedly increased in numerous human cancers, including breast carcinomas. We have previously shown that overexpression of ADAM12 accelerates tumor progression in a mouse model of breast cancer (PyMT). In the present study, we found that ADAM12 deficiency reduces breast tumor progression in the PyMT model. However, the catalytic activity of ADAM12 appears to be dispensable for its tumor-promoting effect. Interestingly, we demonstrate that ADAM12 endogenously expressed in tumor-associated stroma in the PyMT model does not influence tumor progression, but that ADAM12 expression by tumor cells is necessary for tumor progression in these mice. This finding is consistent with our observation that in human breast carcinoma ADAM12 is almost exclusively located in tumor cells and only rarely seen in the tumor-associated stroma. We hypothesized, however, that the tumor-associated stroma may stimulate ADAM12 expression in tumor cells, based on the fact that TGF-β1 stimulates ADAM12 expression and is a well-known growth factor released from tumor-associated stroma. TGF-β1 stimulation of ADAM12-negative Lewis lung tumor cells induced ADAM12 synthesis, and growth of these cells in vivo induced a >200-fold increase in ADAM12 expression. Our observation that ADAM12 expression is significantly higher in the terminal duct lobular units (TDLUs) adjacent to human breast carcinoma compared with TDLUs found in normal breast tissue supports our hypothesis that tumor-associated stroma triggers ADAM12 expression.

This study examined (1) the interrelationships among 5-HTTLPR genotype, perceived parental rejection, and impulsivity, and (2) meditational models in which perceived paternal/maternal rejection mediates the relationship between the 5-HTTLPR genotype and impulsive behaviour. Participants included 403 adults (152 males and 252 females, mean age = 24.20) who provided genetic data and a set of the questionnaires (BIS11; Barratt Impulsiveness Scale-11 and EMBU; Egna Minnen av Bätraffande Uppfostran). Using SEM (Structural Equation Modeling), we evaluated 3 models for both direct and indirect relationships between 5-HTTLPR (5HTT) and Impulsivity (IMP), via maternal/fraternal rejection (MAT/FAT). In model 1, the direct path from 5HTT and IMP was not significant across the mother’s and father’s analysis. Models 2 and 3 assessed the indirect influence of 5HTT on IMP through MOT/FAT. The paths of models 2 and 3 were all significant and showed a good fit between the hypothesized model and data. Furthermore, the effects of the 5-HTTLPR genotype on impulsiveness in this Japanese sample were particularly accounted for by perceived rejection from the mother or father. The effects from the parents appeared to be robust especially among males. These results may help elucidate the specific pathways of risk in relation to genetic and environment influences on impulsive phenotypes.

Induced pluripotent stem (iPS) cells are generated from adult somatic cells by transduction of defined factors. Given their unlimited proliferation and differentiation potential, iPS cells represent promising sources for cell therapy and tools for research and drug discovery. However, systems for the directional differentiation of iPS cells toward paraxial mesodermal lineages have not been reported. In the present study, we established a protocol for the differentiation of mouse iPS cells into paraxial mesodermal lineages in serum-free culture. The protocol was dependent on Activin signaling in addition to BMP and Wnt signaling which were previously shown to be effective for mouse ES cell differentiation. Independently of the cell origin, the number of transgenes, or the type of vectors used to generate iPS cells, the use of serum-free monolayer culture stimulated with a combination of BMP4, Activin A, and LiCl enabled preferential promotion of mouse iPS cells to a PDGFR-α+/Flk-1− population, which represents a paraxial mesodermal lineage. The mouse iPS cell-derived paraxial mesodermal cells exhibited differentiation potential into osteogenic, chondrogenic, and myogenic cells both in vitro and in vivo and contributed to muscle regeneration. Moreover, purification of the PDGFR-α+/KDR− population after differentiation allowed enrichment of human iPS cell populations with paraxial mesodermal characteristics. The resultant PDGFR-α+/KDR− population derived from human iPS cells specifically exhibited osteogenic, chondrogenic, and myogenic differentiation potential in vitro, implying generation of paraxial mesodermal progenitors similar to mouse iPS cell-derived progenitors. These findings highlight the potential of protocols based on the serum-free, stepwise induction and purification of paraxial mesodermal cell lineages for use in stem cell therapies to treat diseased bone, cartilage, and muscle.

Network oscillations support transient communication across brain structures. We show here, in rats, that task-related neuronal activity in the medial prefrontal cortex (PFC), hippocampus and ventral tegmental area (VTA), regions critical for working memory, is coordinated by a 4-Hz oscillation. A prominent increase of power and coherence of the 4-Hz oscillation in PFC and VTA and its phase-modulation of gamma power in both structures was present in the working memory part of the task. Subsets of both PFC and hippocampal neurons predicted the turn choices of the rat. The goal-predicting PFC pyramidal neurons were more strongly phase-locked to both 4-Hz and hippocampal theta oscillations than non-predicting cells. The 4-Hz and theta oscillations were phase-coupled and jointly modulated both gamma waves and neuronal spikes in PFC, VTA and hippocampus. Thus, multiplexed timing mechanisms in the PFC-VTA-hippocampus axis may support processing of information, including working memory.

We demonstrate here the identification and phylogenetic characterization of Babesia microti (B. microti)-like parasite detected from a splenectomized Japanese macaque (Macaca fuscata fuscata) at a facility for laboratory animal science. On Day 133 after splenectomy, intra-erythrocytic parasites were found on light microscopic examination, and the level of parasitemia reached 0.3% on blood smear. Molecular characterization of the parasite using nested-polymerization chain reactions targeting the 18S rRNA, β-tubulin, and subunit 7 (eta) of the chaperonin-containing t-complex polypeptide 1 (CCT7) genes were identified as a B. microti-like parasite, designated the Japanese Macaque Babesia-1 (JM-1).

The deficient mutant for the rice heterotrimeric G protein α subunit gene (RGA1), d1, showed dwarfism and set small seed due to a reduced cell number. Mutants for the rice heterotrimeric G protein β subunit gene (RGB1) have not been isolated. To determine the functions of RGB1, transgenic rice plants with suppressed expression of RGB1 were studied using the RNAi method. RGB1 knock-down lines showed browning of the lamina joint regions and nodes and reduced fertility, but these abnormality were not observed in d1. Transgenic plants in which the G protein β subunit was greatly decreased were not obtained, suggesting that the complete suppression of RGB1 mRNA may be lethal. In contrast, the d1 mutants, with complete loss of the G protein α subunit, were fertile and half the size of the WT. These studies suggest that RGB1 has different functions than RGA1.

We recently demonstrated that cilnidipine, an L/N-type calcium channel blocker, elicits protective effects against glomerular podocyte injury, in particular, in obese hypertensive rats that express the N-type calcium channel (N-CC). Since the N-CC is known to be expressed in sympathetic nerve endings, we evaluated the reno-protective effects of cilnidipine in innervated and denervated spontaneously hypertensive rats (SHR). Male SHR were uninephrectomized and fed 4% high-salt diet (HS-UNX-SHR). Animals were divided into groups, as follows, and observed from 9 to 27 weeks of age: 1) vehicle (n = 14), 2) vehicle plus renal-denervation (n = 15), 3) cilnidipine (50 mg/kg per day, p.o.; n = 10), and 4) cilnidipine plus renal-denervation (n = 15). Renal denervation attenuated elevations in blood pressure, but failed to suppress urinary protein excretion and podocyte injury in HS-UNX-SHR. Cilnidipine in both innervated and denervated HS-UNX-SHR similarly induced significant antihypertensive effects, as well as suppressing the urinary protein excretion and podocyte injury, compared to vehicle-treated HS-UNX-SHR. These data indicate that renal nerves have a limited contribution to the cilnidipine-induced reno-protective effects in HS-UNX-SHR.

Several randomized trials have shown that breast-conserving therapy (BCT) is as effective as mastectomy and should be a standard treatment for early-stage breast cancer. Recently, there has been an increase in reports of angiosarcoma (AS) after BCT. Herein, we report a case of AS which developed after BCT and a case of Stewart-Treves syndrome with a focus on lymphedema. Chronic lymphedema is the primary risk factor for AS, which was first described in 1948 by Stewart and Treves [Cancer 1948;1:64–81]. Radiation therapy secondarily tends to induce the development of AS, since radiation therapy induces fibrosis and proliferation of lymphatic vessels via cytokines such as vascular endothelial growth factor, which is followed by subclinical chronic edema. It is suggested that axillary lymph node dissection predisposes patients to the development of AS, since it is closely associated with lymphedema. Breast surgeons and radiologists should be aware of skin changes in order to improve the early detection of AS during the follow-up of patients who have undergone BCT, and especially those treated with axillary lymph node dissection.

We investigated the effectiveness of peptide nucleic acid (PNA) clamp PCR for detecting KRAS mutations in peripheral blood samples of colorectal cancer (CRC) patients. We compared KRAS point mutations between tumour tissue and blood samples. Forty-two patients were included in this study. We observed KRAS mutations in formalin-fixed, paraffin-embedded tissues by PCR direct sequencing and in blood samples by PNA clamp PCR. KRAS point mutations were detected in primary tumour tissue samples of 13 patients (31.0%) and in peripheral blood samples of 10 patients (23.8%). KRAS point mutations were detected in both samples for 8 patients (19.0%). The sensitivity, specificity and accuracy for detecting KRAS mutations in peripheral blood and tumour tissue samples were 61.5, 93.1 and 83.3%, respectively. The positive and negative predictive values were 80.0 and 84.4%, respectively. Five patients with mutant KRAS in their plasma preoperatively, did not exhibit KRAS mutations postoperatively. Our method detected KRAS point mutations in peripheral blood samples of CRC patients, which contained extremely small amounts of mutant cells. This method is helpful for identifying metastatic CRC patients in whom metastases will respond to EGFR-targeted monoclonal antibody therapy.

Morphological and immunohistochemical examinations were carried out on the pancreas of a hyperglycemic 5-year-old male cynomolgus monkey. Body weight gradually decreased from 6 months before termination, accompanying a slight reduction in food consumption and anorexia for the last 2 days. The blood glucose level was markedly elevated when examined at termination. Histopathologically, in the exocrine pancreas, diffuse hyperplasia of centroacinar and intercalated duct cells and diffuse atrophy of acinar cells with sporadic apoptosis were observed, although most centroacinar and intercalated duct cells were proliferating cell nuclear antigen (PCNA)-positive in both the present case and age-matched control animals. In the endocrine pancreas, the islets tended to be hypertrophic, with an increase in insulin-positive cells in comparison with the age-matched control animals. PCNA-positive cells also tended to increase in the islets, although positive cells for phospho-histone H3, a marker for mitotic cells, were not detected in the endocrine and exocrine pancreas. Moreover, neither inflammation nor amyloidosis was noted in the islets. In conclusion, the present case probably suffered from early-stage type 2 diabetes mellitus, and it provides fundamental information concerning pancreatic histopathology under insulin-related derangement in monkeys.

Angiosarcoma is an uncommon malignancy, which spread out from the endothelial cells of vessels. Scalp angiosarcoma with cervical lymph node metastasis is particularly rare. This article describes a rare case of angiosarcoma of the scalp, presenting as neck inflammation. Imaging procedures such as computed tomography (CT), magnetic resonance image (MRI) and ultrasonography (US) were not sufficient to diagnose this case. A needle biopsy provided an effective and accurate diagnosis of cervical lymph node metastasis. Additional observation and physical examination was required to diagnose the origin of the primary cancerous lesion. Once the angiosarcoma diagnosis was confirmed histologically, sequential weekly and monthly docetaxel (DTX) treatment was effective in preventing reoccurrence. Nonetheless, the optimization of angiosarcoma treatment remains a future goal. Although patients generally describe pain and swelling at the primary lesion site, this patient complained only of painful neck inflammation, without any indication of pain or swelling of the scalp. A revised diagnostic protocol should note that cervical lymph node metastasis of unknown primary origin may result from angiosarcoma of the scalp.

Uterine leiomyoma, a benign tumor, may be treated with drugs, albeit surgical resection is more common. The present study aimed to evaluate the treatment of leiomyoma cases by uterine artery embolization (UAE) using a gelatin sponge prepared by the pumping method. The results of 700 leiomyoma cases treated by UAE in the outpatient department were evaluated. UAE was performed by injecting gelatin sponge prepared by the pumping method into the uterine artery. Among 700 cases, effective cases were 680 (97.2%), ineffective cases were 18 (2.8%) and impossible cases for UAE were 2 (0.2%). Retreatment was required in 23 cases (3.3%). Complication events designated by the Society of Interventional Radiology Clinical Practice Guidelines occurred in 31 cases (4.4%): 1 case showed permanent adverse sequelae, 4 cases required major therapy with a prolonged hospitalization (>48 h) and 10 patients required therapy with minor hospitalization (<48 h). The remaining 16 cases required nominal or no therapy. Follow-up of patients was performed for 599 cases for an average period of 1.2±0.9 years, ranging between 1 month and 6 years. Pregnancy after UAE was observed in 12 cases/15 cycles. Thus, the findings indicate that UAE using gelatin sponge prepared by the pumping method applied to outpatients is a safe and useful treatment procedure.

Extramammary Paget's disease is a rare cutaneous malignant neoplasm. Previous studies indicated the efficacy of docetaxel in advanced cases. The common side effects of docetaxel are usually tolerable and seldom life-threatening. We experienced a case of severe pseudomembranous colitis and neutropenic fever that developed just after the first cycle of docetaxel chemotherapy. To the best of our knowledge, there are few reports of pseudomembranous colitis associated with docetaxel administration for skin cancers. The patient showed complete resolution of her symptoms within 2 weeks with an oral metronidazole therapy. During the second and third cycles, the patient received docetaxel safely with lower doses. The present case indicated that pseudomembranous colitis should be included in the differential diagnosis when assessing patients who develop severe diarrhea during systemic chemotherapy with docetaxel.

Canine osteosarcoma (OSA) is known to present with highly variable and chaotic karyotypes, including hypodiploidy, hyperdiploidy, and increased numbers of metacentric chromosomes. The spectrum of genomic instabilities in canine OSA has significantly augmented the difficulty in clearly defining the biological and clinical significance of the observed cytogenetic abnormalities. In this study, eight canine OSA cell lines were used to investigate telomere fusions by fluorescence in situ hybridization (FISH) using a peptide nucleotide acid probe. We characterized each cell line by classical cytogenetic studies and cellular phenotypes including telomere associated factors and then evaluated correlations from this data. All eight canine OSA cell lines displayed increased abnormal metacentric chromosomes and exhibited numerous telomere fusions and interstitial telomeric signals. Also, as evidence of unstable telomeres, colocalization of γ-H2AX and telomere signals in interphase cells was observed. Each cell line was characterized by a combination of data representing cellular doubling time, DNA content, chromosome number, metacentric chromosome frequency, telomere signal level, cellular radiosensitivity, and DNA-PKcs protein expression level. We have also studied primary cultures from 10 spontaneous canine OSAs. Based on the observation of telomere aberrations in those primary cell cultures, we are reasonably certain that our observations in cell lines are not an artifact of prolonged culture. A correlation between telomere fusions and the other characteristics analyzed in our study could not be identified. However, it is important to note that all of the canine OSA samples exhibiting telomere fusion utilized in our study were telomerase positive. Pending further research regarding telomerase negative canine OSA cell lines, our findings may suggest telomere fusions can potentially serve as a novel marker for canine OSA.

Omental infarction (OI) is a rare cause of acute abdomen in children. A 9-year-old girl was presented with sudden-onset intermittent right lower quadrant abdominal pain and fever (37.9°C). Physical examination revealed abdominal tenderness in the right lower quadrant with localized rebound tenderness which resembled acute appendicitis. She was obese and her BMI was on the 99th percentile. Computed tomography (CT) revealed a 5 cm ill-defined heterogeneous fatty mass with hyperattenuating streaks just beneath the abdominal wall. She was diagnosed as OI and treated conservatively with reduced meals and antibiotics. Her symptom resolved gradually and she was discharged on day 7 without complications. OI should be considered as a differential diagnosis for acute right-sided abdominal pain, especially in obese children. Enhanced CT is useful for differentiating OI from other conditions presenting with acute abdomen.

Etiology of aberrant social behavior consistently points to a strong polygenetic component involved in fundamental developmental pathways, with the potential of being enhanced by defects in bioenergetics. To this end, the occurrence of social deficits and mitochondrial outcomes were evaluated in conditional Pten (Phosphatase and tensin homolog) haplo-insufficient mice, in which only one allele was selectively knocked-out in neural tissues. Pten mutations have been linked to Alzheimer's disease and syndromic autism spectrum disorders, among others. By 4–6 weeks of age, Pten insufficiency resulted in the increase of several mitochondrial Complex activities (II–III, IV and V) not accompanied by increases in mitochondrial mass, consistent with an activation of the PI3K/Akt pathway, of which Pten is a negative modulator. At 8–13 weeks of age, Pten haplo-insufficient mice did not show significant behavioral abnormalities or changes in mitochondrial outcomes, but by 20–29 weeks, they displayed aberrant social behavior (social avoidance, failure to recognize familiar mouse, and repetitive self-grooming), macrocephaly, increased oxidative stress, decreased cytochrome c oxidase (CCO) activity (50%) and increased mtDNA deletions in cerebellum and hippocampus. Mitochondrial dysfunction was the result of a downregulation of p53-signaling pathway evaluated by lower protein expression of p21 (65% of controls) and the CCO chaperone SCO2 (47% of controls), two p53-downstream targets. This mechanism was confirmed in Pten-deficient striatal neurons and, HCT 116 cells with different p53 gene dosage. These results suggest a unique pathogenic mechanism of the Pten-p53 axis in mice with aberrant social behavior: loss of Pten (via p53) impairs mitochondrial function elicited by an early defective assembly of CCO and later enhanced by the accumulation of mtDNA deletions. Consistent with our results, (i) SCO2 deficiency and/or CCO activity defects have been reported in patients with learning disabilities including autism and (ii) mutated proteins in ASD have been found associated with p53-signaling pathways.

The Aryl hydrocarbon receptor (AhR) has been best known for its role in mediating the toxicity of dioxin. Here we show that AhR overexpression is found among estrogen receptor (ER)α-negative human breast tumors and that its overexpression is positively correlated to that of the NF-κB subunit RelB and Interleukin (IL)-8. Increased DNA binding activity of the AhR and RelB is coupled to IL-8 overexpression in primary breast cancer tissue, which was also supported by in situ hybridization. Activation of AhR in vitro by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced IL-8 expression in MDA-MB 436 and MCF-7 cells in an AhR and RelB dependent manner. Consistently, downregulation of RelB or AhR by small interfering RNAs (siRNA) decreased the level of IL-8 but increased expression of ERα in vitro in MCF-7 cells. Our results strongly suggest that RelB and AhR have a critical role in the regulation of IL-8 and reveal a supportive role of RelB and AhR in the anti-apoptotic response in human breast cancer cells. AhR and RelB may present a novel therapeutic target for inflammatory driven breast carcinogenesis and tumor progression. Overexpression of pro-survival factors AhR and RelB may explain the process of the development of environmentally-induced type of breast cancers.