NE Cell Research Articles

Dynamic phenotypic reprogramming and chemoresistance induced by lung fibroblasts in small cell lung cancer.

Small cell lung cancer (SCLC) is heterogenous in phenotype and microenvironment. Dynamic phenotypic reprogramming, leading to heterogeneity, is prevalent in SCLC, while the mechanisms remain incompletely understood. Cancer-associated fibroblasts (CAFs) possess comprehensive roles in cancer progression, while their function in phenotypic reprogramming of SCLC remain elusive. Here, we obtained transcriptome data of SCLC tissues from publicly available databases, subsequently estimated abundance of CAFs. We found CAF-abundant SCLC exhibited non-neuroendocrine (Non-NE) characteristics. Supporting this, the positive correlation of expression level of α-SMA, the CAF marker, and expression level of REST, protein typically expressed in Non-NE type SCLC, was identified in SCLC tissue arrays. Moreover, we revealed that fibroblasts inhibited NE markers expression and cell proliferation of SCLC cells in the co-culture system comprising lung fibroblasts and SCLC cells, indicating a phenotypic reprogramming from NE to Non-NE. During this process, fibroblast-derived IL-6 activated the JAK2/STAT3 signaling, upregulated c-MYC expression, and subsequently activated the NOTCH pathway, driving phenotypic reprogramming. Moreover, CAF-enriched SCLC exhibited increased immune cell infiltration, elevated expression of immune activation-related signatures, and checkpoint molecules. Our data also highlighted the chemoresistance induced by fibroblasts in SCLC cells, which was effectively reversed by JAK inhibitor. In conclusion, fibroblasts induced phenotypic reprogramming of SCLC cells from NE to Non-NE, likely contributes to inflamed immune microenvironment and chemoresistance. These findings provide novel insights into the clinical implications of CAFs in SCLC.

Neurokinin-1 receptor drives PKCɑ-AURKA/N-Myc signaling to facilitate the neuroendocrine progression of prostate cancer

The widespread application of antiandrogen therapies has aroused a significant increase in the incidence of NEPC, a lethal form of the disease lacking efficient clinical treatments. Here we identified a cell surface receptor neurokinin-1 (NK1R) as a clinically relevant driver of treatment-related NEPC (tNEPC). NK1R expression increased in prostate cancer patients, particularly higher in metastatic prostate cancer and treatment-related NEPC, implying a relation with the progression from primary luminal adenocarcinoma toward NEPC. High NK1R level was clinically correlated with accelerated tumor recurrence and poor survival. Mechanical studies identified a regulatory element in the NK1R gene transcription ending region that was recognized by AR. AR inhibition enhanced the expression of NK1R, which mediated the PKCα-AURKA/N-Myc pathway in prostate cancer cells. Functional assays demonstrated that activation of NK1R promoted the NE transdifferentiation, cell proliferation, invasion, and enzalutamide resistance in prostate cancer cells. Targeting NK1R abrogated the NE transdifferentiation process and tumorigenicity in vitro and in vivo. These findings collectively characterized the role of NK1R in tNEPC progression and suggested NK1R as a potential therapeutic target.

Systemic lupus erythematosus with diffuse alveolar hemorrhage.

Systemic lupus erythematosus with diffuse alveolar hemorrhage.

ASSESSMENT OF DIAGNOSTIC EFFICACY IN LYMPHADENOPATHY BY FINE NEEDLE ASPIRATION CYTOLOGY AND CELL BLOCKS VERSU HISTOPATHOLOGY AT A TERTIARY CARE HOSPITAL

Background- Fine Needle Aspiration cytology (FNAC) is easy to do for diagnosis of lymphadenopathy, but it does not yield sufcient information for precise diagnosis. Cell block (CB) preparation in a way mimics the histopathological sections, thus help in sub classifying various lesions. Methods- This was observational study with evaluation of diagnostic efcacy in lymphadenopathy by ne needle aspiration cytology and cell blocks versus histopathology at a tertiary care hospital from June 2018 to Jan 2020. Results- In this study, (Combined FNAC plus Cell Block) showed concordance with histopathogical diagnosis in 90% cases. For Combined FNAC and Cell Block Sensitivity was 95%, Specicity was 100%, Diagnostic Accuracy was 95%.Conclusion- FNAC as the rst line approach supplemented by Cell Block in selected cases, where the information given by FNAC is in doubt or insufcient to guide clinical management. This strategy is likely to reduce the risk of misdiagnosis and the impact of cytological pitfalls

Feasibility of Canine Adenovirus Type 2 (CAV2) Based Vector for the Locus Coeruleus Optogenetic Activation in Non-Transgenic Rats: Implications for Functional Studies

The locus coeruleus norepinephrine (LC-NE) system modulates many visceral and cognitive functions, while LC-NE dysfunction leads to neurological and neurodegenerative conditions such as sleep disorders, depression, ADHD, or Alzheimer’s disease. Innovative viral-vector and gene-engineering technology combined with the availability of cell-specific promoters enabled regional targeting and selective control over phenotypically specific populations of neurons. We transduced the LC-NE neurons in adult male rats by delivering the canine adenovirus type 2-based vector carrying the NE-specific promoter PRSx8 and a light-sensitive channelrhodopsin-2 receptor (ChR2) directly in the LC or retrogradely from the LC targets. The highest ChR2 expression level was achieved when the virus was delivered medially to the trigeminal pathway and ~100 μm lateral to the LC. The injections close or directly in the LC compromised the tissue integrity and NE cell phenotype. Retrograde labeling was more optimal given the transduction of projection-selective subpopulations. Our results highlight a limited inference of ChR2 expression from representative cases to the entire population of targeted cells. The actual fraction of manipulated neurons appears most essential for an adequate interpretation of the study outcome. The actual fraction of manipulated neurons appears most essential for an adequate interpretation of the study outcome. Thus, besides the cell-type specificity and the transduction efficiency, the between-subject variability in the proportion of the remaining viral-transduced targeted cell population must be considered in any functional connectivity study.

Resistance to androgen receptor signaling inhibition does not necessitate development of neuroendocrine prostate cancer.

Resistance to AR signaling inhibitors (ARSis) in a subset of metastatic castration-resistant prostate cancers (mCRPCs) occurs with the emergence of AR– neuroendocrine prostate cancer (NEPC) coupled with mutations/deletions in PTEN, TP53, and RB1 and the overexpression of DNMTs, EZH2, and/or SOX2. To resolve whether the lack of AR is the driving factor for the emergence of the NE phenotype, molecular, cell, and tumor biology analyses were performed on 23 xenografts derived from patients with PC, recapitulating the full spectrum of genetic alterations proposed to drive NE differentiation. Additionally, phenotypic response to CRISPR/Cas9-mediated AR KO in AR+ CRPC cells was evaluated. These analyses document that (a) ARSi-resistant NEPC developed without androgen deprivation treatment; (b) ARS in ARSi-resistant AR+/NE+ double-positive “amphicrine” mCRPCs did not suppress NE differentiation; (c) the lack of AR expression did not necessitate acquiring a NE phenotype, despite concomitant mutations/deletions in PTEN and TP53, and the loss of RB1 but occurred via emergence of an AR–/NE– double-negative PC (DNPC); (d) despite DNPC cells having homogeneous genetic driver mutations, they were phenotypically heterogeneous, expressing basal lineage markers alone or in combination with luminal lineage markers; and (e) AR loss was associated with AR promoter hypermethylation in NEPCs but not in DNPCs.

Variation in the bombesin staining of pulmonary neuroendocrine cells in pediatric pulmonary disorders-A useful marker for airway maturity.

Pulmonary neuroendocrine cells (NEC) increase with age due to pulmonary maturity. The aim of this study was to determine whether open lung biopsies from patients with interstitial lung diseases have increased pulmonary NEC compared with neuroendocrine cell hyperplasia of infancy (NEHI). Our second aim was to assess pulmonary NECs in the lung autopsy of children without lung disease who died from different causes. Lung tissue of 5 infants with NEHI; 21 patients with pediatric interstitial lung disease (chILD); 17 lung autopsies of infants at varying age without lung disease were included. The percentage of the airways containing neuroendocrine cells, the average percentage of neuroendocrine cells (NECs) per airway, and the number of neuroendocrine bodies (NEBs) in each case were analyzed. The mean percentage of the airways containing neuroendocrine cells were 95% in the NEHI group, 30% in the chILD group, 89% under Intrauterine 37 weeks, 70% between intrauterine 37 to 40 weeks, 52% at postnatal 4 days to 6 months of autopsy ages. In theNEHI group, diffuse NE cell distribution and large NEBs were noticed in the lung biopsy. In thechILD group, neuroendocrine cells were dispersed, did not form clusters and NE cells showed solitary distribution. In thelung autopsy group, linear NE cells were detected at younger aged fetuses and solitary distribution of NE cells was detected with the older increasing age. Our findings confirm that NECs are seen in many other childhood interstitial lung diseases; NE cell hyperplasia may be a marker of decreased pulmonary development and NE cells decrease with the increasing age of the fetus during Intrauterine life.

Reduced noradrenergic innervation of ventral midbrain dopaminergic cell groups and the subthalamic nucleus in MPTP-treated parkinsonian monkeys

There is anatomical and functional evidence that ventral midbrain dopaminergic (DA) cell groups and the subthalamic nucleus (STN) receive noradrenergic innervation in rodents, but much less is known about these interactions in primates. Degeneration of NE neurons in the locus coeruleus (LC) and related brainstem NE cell groups is a well-established pathological feature of Parkinson's disease (PD), but the development of such pathology in animal models of PD has been inconsistent across species and laboratories. We recently demonstrated 30–40% neuronal loss in the LC, A5 and A6 NE cell groups of rhesus monkeys rendered parkinsonian by chronic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). In this study, we used dopamine-beta-hydroxylase (DβH) immunocytochemistry to assess the impact of this neuronal loss on the number of NE terminal-like varicosities in the substantia nigra pars compacta (SNC), ventral tegmental area (VTA), retrorubral field (RRF) and STN of MPTP-treated parkinsonian monkeys. Our findings reveal that the NE innervation of the ventral midbrain and STN of normal monkeys is heterogeneously distributed being far more extensive in the VTA, RRF and dorsal tier of the SNC than in the ventral SNC and STN. In parkinsonian monkeys, all regions underwent a significant (~50–70%) decrease in NE innervation. At the electron microscopic level, some DβH-positive terminals formed asymmetric axo-dendritic synapses in VTA and STN. These findings demonstrate that the VTA, RRF and SNCd are the main ventral midbrain targets of ascending NE inputs, and that these connections undergo a major break-down in chronically MPTP-treated parkinsonian monkeys. This severe degeneration of the ascending NE system may contribute to the pathophysiology of ventral midbrain and STN neurons in PD.

What clinicians are asking pathologists when dealing with lung neuroendocrine neoplasms?

Lung neuroendocrine tumors (NET) are currently classified in resection specimens according to four histological categories, namely typical carcinoid (TC), atypical carcinoid (AC), large-cell neuroendocrine carcinoma (LCNEC) and small cell carcinoma (SCC). Diagnostic criteria have remained unchanged in the 2015 WHO classification, which has ratified the wide acceptance and popularity of such terminology in the pathologists׳ and clinicians׳ community. A unifying umbrella of NE morphology and differentiation has been recognized in lung NET, which has pushed to enter an unique box of invasive tumors along with diffuse idiopathic pulmonary NE cell hyperplasia (DIPNECH) as a pre-invasive lesion with a potential toward the development of carcinoids. However, uncertainties remain in the terminology of lung NET upon small samples, where Ki-67 antigen could play some role to avoid misdiagnosing carcinoids as high-grade NE tumors. Epidemiologic, clinical and genetic traits support a biological three-tier over a pathology four-tier model, according to which TC are low malignancy tumors, AC intermediate malignancy tumors and LCNEC/SCC high malignancy tumors with no significant differences in survival among them. Inconsistencies in diagnostic reproducibility, troubles in the therapy of AC and LCNEC, and limitations to histology within the same tumor category argue in favor of a global re-thinking of lung NET where a grading system could play a role. This review outlines three main key questions in the field of lung NET: (A) unbiased diagnoses, (B) the role of Ki-67 and tumor grading, and (C) management of predictive markers. Answers are still inconclusive, thus additional research is required to improve our understanding on lung NET.

A Study on Thermo-Mechanical Behavior of AA5754 Alloy (Tread and Plain Sheet) Produced by Twin-Roll Casting

Aluminum alloy AA5754 is used for many technical and industrial applications. Twin roll casting is unique among the casting processes in that it is a combined solidi cation/deformation technique. The simultaneous solidi cation and hot rolling produces characteristic microstructure with a ne cell size and intermetallic particle distribution with some residual structure. In the study, rst AA5754 alloy (tread and plain sheet) strips were fabricated by using a twin-roll caster equipped with water-cooled steel-rolls. To reduce the thickness of the strip, cold rolling process was applied until strip thickness got 3 mm. After homogenization step the strips were cut in to smaller specimens and annealed at 260 ◦C, 285 ◦C, 310 ◦C, 340 ◦C, 370 ◦C, 400 ◦C, 430 ◦C, 460 ◦C, 490 ◦C, 520 ◦C for 3 hours to obtain the desired temper conditions. Mechanical properties were investigated after processes. Tensile, hardness and bending tests were applied to monitor the e ect of annealing after cold rolling process.

Neuroendocrine cells associated with neuroendocrine carcinoma of the breast: nature and significance

BackgroundThe developmental mechanisms of breast neuroendocrine carcinoma (B-NEC) have not been sufficiently analysed and are not well understood.AimsTo investigate NE cells in the background tissues surrounding B-NECs.MethodsThree cases (four breasts)...

Abstract IA10: Pathology of lung neuroendocrine tumors: In search of evidence for classification

Abstract Neuroendocrine (NE) tumors comprise approximately 25% of all tumors in human lung. As a group they continue to provide challenges at biological, molecular and pathological level for uniform classification. The prototype of NE tumors is the highly aggressive small cell lung cancer (SCLC) that accounts 15% of human lung cancers. For years lung cancers were clinically classified mainly into SCLCs and non-SCLCs (NSCLCs) while it has become evident that lung NE tumors actually form a complex spectrum from SCLC to carcinoid with shifting boundaries. The current WHO classification recognizes SCLC, its variant form combined SCLC, typical and atypical carcinoids as well as large cell NE carcinoma (LCNEC) and its variant form combined large cell carcinoma, the last two cancers under the main NSCLC category of large cell carcinoma. With the exception of the LCNEC, it is expected that the diagnoses will be rendered by routine hematoxylin-eosin stain according the established criteria. Benign entities include diffuse idiopathic pulmonary NE cell hyperplasia which is described in the chapter of preinvasive lesions. Over time there have been several efforts to place lung NE tumors into two to four-tier categories according to their malignant potential (high versus low grade) or degree of differentiation often leaving behind confusing terminology that is later misused. Unlike surgically resected NSCLCs, most NE tumors are frequently diagnosed from biopsies which remains a seldom recognized fact that may create its own biases. The diagnosis that experts most often agree with is SCLC, while distinctions between atypical carcinoid and LCNEC that are in the middle of the spectrum are often disputed. Many molecular studies have also “correctly” classified the endpoints of the NE spectrum while grouping in the middle of it has produced varied results. Moreover, several studies have suggested that NSCLCs with NE features (NSCLC-NEs) is a distinct carcinoma type with worse prognosis than ordinary non-NE NSCLC, while others disagree. Biologically this category is very interesting as NSCLCs and SCLCs are ultimately thought to be derived from the same cell. The regulation of NE differentiation is poorly understood. The proneural achaete-scute homolog 1 (ASCL1), a lineage-dependent oncogene may be a key factor for NE differentiation. On the other hand, it was recently shown that the deletion of the tumor suppressor genes Rb1 and p53 specifically in NE cells, a subpopulation of cells in normal airways, or in alveolar non-NE type2 pneumocytes of mice resulted in SCLCs closely mimicking human disease. These results provide experimental evidence for the close relationship of NE and non-NE epithelial cells in carcinogenesis.

HESC derived neuro-epithelial rosettes recapitulate early mammalian neurulation events; an in vitro model

The in vitro neuralization of hESCs has been widely used to generate central and peripheral nervous system components from neural precursors (Bajpai et al., 2009; Curchoe et al., 2010), most often through an intermediate “rosette” stage. Here we confirm that hESC derived neuro-epithelial rosettes express many characteristics of the developing embryonic neural plate (Aaku-Saraste et al., 1996), characterized by expression of the tight junction proteins ZO-1 and N-Cadherin. Moreover, neuro-epithelial rosettes display a characteristic acetylated alpha tubulin cytoskeletal arrangement (similar to that observed in the developing embryonic neural plate) (Bhattacharyya et al., 1994). Demonstrated here for the first time MKLP was observed in a hESC model system. We found MKLP expression in small particles in between mitotic spindles, large particles aggregating in the lumen of neuroepithelial rosettes, and we did not observe MKLP in the nucleus of hESC derived neural precursors as previously described in the HeLa cell line. We observed MKLP + particles in aggregations in the lumen of “early” rosette structures. Furthermore, we observed that MKLP + particle aggregations can also be lost from the lumens of hESC derived neuro-epithelial rosettes, similar to a phenomenon observed in the developing neural tube in vivo (Marzesco et al., 2005). We determined that this loss of MKLP + particles occurs from “late” as opposed to “early” stage neuro-epithelial rosettes (characterized by junction type). Disrupting the apical-basal polarization of “early” stage rosettes with a 1% Matrigel overlay (Krtolica et al., 2007) nearly ablates MKLP particle aggregation in the lumen of rosettes, demonstrating that the apical-basal polarity of early NE cells is necessary for lumenal MKLP particle aggregation. We conclude that early hESC derived neuro-epithelial rosettes can model early neurulation events, such as the transition from neural plate like cells to neural tube like cells (i.e. symmetric to asymmetric NE cell division) demonstrated by polarized MKLP particle inheritance and distribution using junction type as a measure of stage.

Abstract 3623: Monoclonal antibody against the 4th extracellular domain of N-cadherin affects FGF2 mediated pathways in prostate cancer

Abstract Introduction: Fibroblast growth factor 2 (FGF2) has been reported to synergize with N-cadherin, a cell surface marker of epithelial mesenchymal transition (EMT), to enhance migration and invasion in breast cancer and other cancers. Recent studies from our group suggested that N-cadherin promotes castration resistance and metastasis in prostate cancer. In addition, our studies showed that antibodies against N-cadherin ectodomains blocked prostate cancer invasion and castration resistant growth. To investigate the mechanism of action of N-cadherin antibodies in prostate cancer cells, we seek to determine the contribution of the different N-cadherin domains in promoting invasion and growth in prostate cancer cells, with particular focus on interaction with FGF2. Methods: Chimeric constructs, in which a N-cadherin domain was swapped with an E-cadherin domain, were generated and ectopically expressed in androgen dependent prostate cancer cell line LNCaP. The following combinations were made: 1/ NE: N-cadherin ectodomains linked to E-cadherin cytoplasmic domain (NE), 2/ EN: the reverse of NE, 3/ NEN: swapping N-cadherin ectodomain 4 for that of E-cadherin. Full length N-cadherin and empty vector sublines served as positive and negative controls. All cell lines were assayed for invasion and growth in androgen depleted media in combination with recombinant FGF2, FGF2 neutralizing antibody and N-cadherin antibodies. Results: Ectopic expression of N-cadherin in N-cadherin negative cells result in a 5-fold increase of FGF2 secreted in the media. In vitro studies have shown that the addition of recombinant FGF2 enhanced invasion by 56%± 0.04 in N-cadherin positive cells while treatment with FGF2 neutralizing antibody resulted in a 65%± 0.03 reduction in invasion. Chimeric cell lines which harbor extracellular domain 4 of N-cadherin, N and NE cell lines, showed >56%± 0.11 enhanced invasion to the addition of recombinant FGF2 while EN, NEN, and control cell lines did not. Monoclonal antibodies developed against regions in the extracellular domain of N-cadherin block the response to recombinant FGF2 with 2A9 (antibody raised against extracellular domain 4) being the least responsive. Conclusions: These studies suggest that the relationship between N-cadherin and FGF2 is involved in prostate cancer progression. Therapeutic targeting of N-cadherin with monoclonal antibodies, alone or in combination with other drugs targeting those potentially involved in downstream pathways may have significant clinical benefit. Future experiments include in vivo models where chimeric cell lines will be implanted in mice as xenografts, and will be monitored for tumor growth, local invasion, and metastasis. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3623. doi:10.1158/1538-7445.AM2011-3623

Current Diagnostic Procedure on Neuroendocrine Differentiation of Prostate Cancer

Chromogranin A (CgA) is considered as a major specific neuroendocrine tumor marker. It belongs to the secretogranin family, which is present in the gastrointestinal tract, respiratory system, endocrine glands and in a group of endocrine cells such us pancreas and thyroid. Serum levels of CgA could reflect the neuroendocrine activity and could be used when evaluating advance prostate carcinoma. Moreover, there are also several factors that may increase the serum level of CgA: treatment with proton-pump inhibitors or H2-receptor blockers, chronic atrophic gastritis, rheumatoid arthritis, liver and renal failure. Another method to evaluate NE differentiation is scintigraphy with the 111In-labeled somatostatin analogue (DTPA-D-Phe)-octrotide, (Octreoscan). This method takes advantage of the overexpression of type II somatostatin receptors on the cell surface of NE tumors. With this technique the presence of NE differentiation can be detected both at the primary (prostate) and the metastatic sites. A more specific system to detect NE cell activity is obtained by analyzing CgA gene expression in prostate tissue by a semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR).

Abstract 4256: Neuroendocrine, stem, and stromal cell interactions involved in the organization of the normal colonic stem cell niche which become disorganized during colon tumorigenesis

Abstract In development of colorectal cancer (CRC), stem cell (SC) overpopulation underlies tumor initiation and progression, but it is incompletely understood which dysregulated mechanisms cause SC overpopulation. Because neuroendocrine cell (NEC) and SC populations both reside in the SC niche at the normal crypt bottom, we hypothesized that i) NECs play a role in maintaining the SC population, and ii) changes in the NEC population contributes to SC overpopulation and altered epithelial: stromal interactions during tumorigenesis. Immunofluorescence mapping and flow cytometry were used to analyze SC niche structure and cell-cell interactions in normal and neoplastic colonic tissues from Caucasian and African-American patients. In normal colonic crypts, most cells (77%) staining positively for the colonic SC marker ALDH1, also co-stained for the NE cell marker chromogranin-A (CGA). In the progression from normal to normal-appearing FAP to adenomatous to malignant colonic tissue, the proportion of ALDH1+/CGA+ cells progressively diminished while the proportion of ALDH1+/CGA- cells increased. The epithelial phenotype of tumor cells was confirmed by co-staining for pancytokeratin. These data suggest that colonic SC express a NE phenotype, and loss of this phenotype is associated with an increased number of SC during colon tumorigenesis. Our studies using flow cytometry and CRC cell lines (COLO320, DiFi, LIM1863, LoVo, SW480, HCT116 & HT29) revealed that each line is characterized by the proportion of cells having a SC phenotype (ALDEFLUOR+) and NEC phenotype (SSTR+ or GLPR2+). have a low proportion. These findings suggest that these proportions are maintained constant through feedback mechanisms involving SC and NEC subpopulations. Our studies of epithelial-stromal interactions used immunofluorescence mapping of basement membrane proteins (Perlecan; collagen IV), inflammation markers (Cox2; Caveolin 1), pericryptal fibroblasts (smooth muscle actin), endothelial cells (CD34) and macrophages (CD68). Our results show that the stroma undergoes progressive disorganization (particularly pericryptal fibroblasts & basement membrane) in parallel with increasing size of the SC population during colon tumorigenesis. These results suggest that genetic changes occurring during colon tumorigenesis lead to breakdown of stromal-epithelial interactions that are crucial to the maintenance of the stem cell niche, which contributes to colonic tissue disorganization that is a cardinal feature of cancer. Taken together, our investigations yield insights into: (i) the control of normal SC populations (including how the SC niche is maintained), (ii) molecular mechanisms underlying SC overpopulation in tumorigenesis, and (iii) potential targets for novel anti-cancer therapeutic strategies. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4256.

Expression Pattern of Neuroendocrine Cells and Survivin in the Prostate of Rabbits

Purpose: The neuroendocrine cell (NE cell) is thought to play an important role in the development of hormone-refractory prostate cancer. Survivin is one of the IAPs (inhibitors of apoptosis), and it is expressed in the NE cell and in most of the common cancers, but not in normal tissue. The objective of this study was to investigate the expression pattern of the NE cell and survivin in the prostate of rabbits. Materials and Methods: The 9 rabbits underwent orchiectomy and their prostates were removed at 0 weeks (control), 2 weeks and 6 weeks after orchiectomy. Each of the prostatic tissue specimens was stained with HE immunohistochemical staining was done for chromogranin A, synaptophysin and survivin, and the tissue specimens were then examined by microscopy. Results: In the prostate of rabbits, most of the NE cells were located between the epithelial gland and the stroma. NE differentiation occurred 6 weeks after orchiectomy. The location of cells that were positive for survivin was almost same as that of the NE cells. Conclusions: The main location of NE cells in the prostate of rabbits was between the epithelial gland and the stroma, and NE differentiation occurred 6 weeks after orchiectomy, the same as in a human or a dog. The location of survivin positive cells coincided with that of the NE cells. Therefore, a rabbit seems to be a suitable animal model for the study of the NE cell. (Korean J Urol 2006;47:201-205) ꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏ

継続的運動が中高年者の末梢血リンパ球サブセットに与える影響

The purpose of the present study was to investigate the effects of long-term exercise training on immune function in elderly individuals. This study was conducted on 27 sedentary subjects including 7 males and 20 females aged 66.1±4.2 yrs. (range of 60 to 77 yrs.) who participated in a 12-month exercise program. The subjects attended the exercise program 4.4 ± 1.7 times per month. Peripheral blood samples were taken prior to, and at 5 and 12 months during the exercise training program. Each lymphocyte subset (natural killer: NE, T, cytotoxic T: Tc, helper T: Th, memory-Th and NKT) count in the samples was measured using flow cytometry. Results indicated that NE and Tc cell counts were not significantly altered. Whereas, T and Th cell counts were significantly elevated after 12 months, and memory-Th and NET cell counts were significantly elevated after 5 and 12 months of exercise training. These results suggest that long-term exercise training may be a stimu lus to increase and or maintain immune function in elderly individuals.

Androgen ablation promotes neuroendocrine cell differentiation in dog and human prostate.

Mechanisms triggering prostatic NE differentiation are poorly understood. Since dog and man naturally develop prostatic proliferative diseases with age, our objectives were to confirm the presence of NE cells in the dog prostate and test their hormonal regulation in both species. Serotonin staining was examined by immunohistochemistry in 37 dog prostates: 17 from intact and 20 from castrated animals. In intact dogs, 9 prostates were normal and 8 hyperplastic. In the castrated group, 6 dogs were left untreated while androgens and estrogens were administered to 7 dogs, each. Human prostates were from 48 prostate cancer patients; half of them were submitted to androgen ablation prior to prostatectomy. The density of serotonin-positive NE cells was expressed relatively to the number of acini. Serotonin-positive NE cells were morphologically similar in dog and human prostates and identified in all groups, independent of the hormonal status. NE cell densities were within the same range in normal and hyperplastic dog prostates but significantly higher after castration. Androgens and estrogens after castration restored NE cell density to normal values and induced luminal differentiation and basal metaplasia, respectively. In human, the density of serotonin-positive NE cells was also significantly higher in benign glands after androgen ablation. The dog is a suitable animal model and mimics the human, since androgen ablation favored prostatic NE differentiation in both species. The down-regulation elicited by steroids suggests that the process may be reversible and hormonally-repressed.

Effects of Repetitive Hypoglycemia on Neuroendocrine Response and Brain Tyrosine Hydroxylase Activity in the Rat

Hypoglycemia-associated autonomic failure (HAAF) is a syndrome of acute adaptation to a metabolic stressor, in which neuroendocrine responses to repetitive hypoglycemic bouts are blunted. The CNS mechanisms that contribute to HAAF are unknown. In the present study, we modeled HAAF in the rat and measured the activity of tyrosine hydroxylase (TH) as an index of acute noradrenergic activation, to test the hypothesis that noradrenergic activation of the hypothalamus might be impaired. In association with a significant counter-regulatory response to a single bout of hypoglycemia (elevated corticosterone, catecholamines, and glucagon), TH activity was elevated overall in brainstem NE cell body areas and hypothalamus. With multiple hypoglycemic episodes in a 24 h period, the counter-regulatory response was blunted, and hypothalamic TH activity was comparable to that of saline-infused controls. In a similar paradigm, multiple bouts of CNS neuroglucopenia did not blunt the hyperglycemic or corticosterone responses, and were required for elevation of TH activity. This alternate response pattern suggests that insulin-induced hypoglycemia and cerebral neuroglucopenia represent somewhat different metabolic stressors at the CNS.