Napsin A Expression in Human Tumors and Normal Tissues.

Background: Novel aspartic proteinase of the pepsin family A (Napsin A, TAO1/TAO2) is a functional aspartic proteinase which is involved in the maturation of prosurfactant protein B in type II pneumocytes and the lysosomal protein catabolism in renal cells. Napsin A is highly expressed in adenocarcinomas of the lung and is thus commonly used to affirm this diagnosis. However, studies have shown that other tumors can also express Napsin A. Methods: To comprehensively determine Napsin A expression in normal and tumor tissue, 11,957 samples from 115 different tumor types and subtypes as well as 500 samples of 76 different normal tissue types were evaluable by immunohistochemistry on tissue microarrays. Results: Napsin A expression was present in 16 different tumor types. Adenocarcinoma of the lung (85.6%), clear cell adenocarcinoma of the ovary (71.7%), clear cell adenocarcinoma of the endometrium (42.8%), papillary renal cell carcinoma (40.2%), clear cell (tubulo) papillary renal cell carcinoma (16.7%), endometrial serous carcinoma (9.3%), papillary thyroid carcinoma (9.3%) and clear cell renal cell carcinoma (8.2%) were among the tumors with the highest prevalence of Napsin A positivity. In papillary and clear cell renal cell carcinoma, reduced Napsin A expression was linked to adverse clinic-pathological features (p ≤ 0.03). Conclusion: This methodical approach enabled us to identify a ranking order of tumors according to their relative prevalence of Napsin A expression. The data also show that loss of Napsin A is linked to tumor dedifferentiation in renal cell carcinomas.

Immunohistochemistry Profile Predicts EGFR Mutation Status in Lung Adenocarcinoma.

Significant advances in targeted therapy have been made in recent years for patients with lung adenocarcinoma. These targeted therapies have made molecular testing of paramount importance to drive therapeutic decisions. Material for testing is often limited, particularly in cytology specimens and small core biopsies. A reliable screening tool is invaluable in triaging limited tissue and selection for epidermal growth factor receptor (EGFR) mutation testing. We hypothesized that the immunohistochemistry (IHC) profile of lung adenocarcinoma predicts EGFR mutation status. In this retrospective study, we evaluated the thyroid transcription factor-1 (TTF-1)/napsin A IHC profile and EGFR mutation status in 339 lung adenocarcinomas at our academic institution. In our cohort, we found that 92.3% of cases were positive for TTF-1 and/or napsin A by IHC with an EGFR positivity rate of 17.3%. Importantly, 7.7% of the cases were dual TTF-1/napsin A negative, and none of these cases contained EGFR mutations. This finding supports the use of TTF-1 and napsin A IHC to identify cases where EGFR mutation status will be negative, thus preserving limited tissue for other ancillary testing.

Napsin A Expression in Subtypes of Thyroid Tumors: Comparison with Lung Adenocarcinomas.

Napsin A is widely used in the diagnosis of lung adenocarcinoma and has also been reported to be positive in cases of thyroid carcinomas. We investigated napsin A levels through immunohistochemistry on whole sections of 210 primary thyroid tumors of various subtypes and another 41 metastatic thyroid carcinomas, and compared these with 125 primary and 25 metastatic lung adenocarcinomas. The results showed that napsin A was expressed in 23.8% thyroid tumors and 30.3% papillary thyroid carcinomas. Most cases showed a focal and weak to moderate expression. In comparison, 80.8% primary lung adenocarcinomas expressed napsin A, with mostly diffused and strong expression. For metastatic carcinomas of thyroid and lung origin, napsin A was detected in 39.0% of thyroid carcinomas in contrast to 88.0% in cases of lung adenocarcinomas. Comparisons of additional markers, TTF-1, CK7, thyroglobulin, and Pax-8 in metastatic carcinomas showed the overlapping expression of immunomarkers of TTF-1 and CK7. Thyroglobulin and Pax-8 were useful for distinguishing between metastatic carcinomas; however, Pax-8 may be a superior marker due to its higher sensitivity. The clinicopathological analysis of papillary thyroid carcinomas showed that the expression of napsin A was positively correlated with lymph node metastasis (p = 0.030). Here, we focused on the expression of napsin A in thyroid tumors and compared it with that in lung adenocarcinomas. The expression of napsin A is common in thyroid tumors and the combined expression of napsin A and TTF-1 in a metastatic thyroid carcinoma is a cause for concern due to chances of misdiagnosis as lung adenocarcinoma.

Napsin A, Hepatocyte Nuclear Factor-1-Beta (HNF-1ß), Estrogen and Progesterone Receptors Expression in Arias-Stella Reaction.

BACKGROUND: The Arias-Stella reaction (ASR) can mimic endometrial clear cell carcinoma (ECCC) in small biopsies, especially when drug or pregnancy history is unknown. A panel of immunohistochemical markers comprising napsin A, hepatocyte nuclear factor-1-beta (HNF-1ß), estrogen and progesterone receptors (ER, PR) has been found useful in confirming a diagnosis of ECCC. However, the detailed characterization of how expression of this combination of markers in the ECCC mimics ASR has yet to be thoroughly evaluated. DESIGN: The frequency and extent of napsin A, HNF-1ß, ER, and PR expression in ASR were assessed in a large series. For napsin A, any cytoplasmic staining was considered positive while only nuclear staining was deemed to be positive for HNF-1ß, ER, and PR. Immunohistochemical histoscores based on the intensity and extent of staining were calculated. RESULTS: Forty cases were gestational and 10 were nongestational ASR. In 19 (38%), the reaction was extensive and involved >50% of the glands. A stromal decidual change was found in 31 (77.5%) of the gestational and 3 (30%) of the nongestational cases. Napsin A was positive in all gestational and 8 of 10 (80%) nongestational ASR. All ASR showed HNF-1ß expression. ER expression was reduced in 37 (92.5%) and lost in 3 (7.5%) gestational ASR, and reduced in 9 (90%) and lost in 1 (10%) of nongestational ASR. None of the ASR in our series expressed PR. CONCLUSIONS: Naspin A and HNF-1ß were frequently expressed in both gestational and nongestational ASR, and ER expression was usually either reduced or loss. Interpretation of these markers in small biopsies containing atypical clear cells should be made with caution.

The effect of early growth response 1 on levels of Amyloid-ß 40 peptide in U87MG cells.

A recent study has shown that early growth response 1 (EGR1) plays a critical role in the ß-amyloid cascade and tau hypotheses. In addition, evidence has suggested that EGR1 can regulate levels of amyloid-beta peptides, key molecules in the pathogenesis of Alzheimer's disease (AD). However, whether EGR1 is a deleterious or protective factor in the AD is still controversial. In this present study, we constructed an overexpression plasmid, CMV-EGFP-EGR1-Kanamycin, and transfected it into U87MG cells to investigate the effects of EGR1 expression on amyloid-ß (1-40) peptide (Aß40) levels. U87MG cells transfected by CMV-EGFP-EGR1-Kanamycin and CMV-EGFP-Kanamycin were assigned, respectively, to experimental and control groups. Fluorescence microscopy was used to observe transfection efficiencies of the plasmids after 6 hours. EGR1 messenger RNA levels were measured by quantitative reverse transcription polymerase chain reaction. Aß40 secretion was analyzed by enzyme-linked immunosorbent assay. Expression of the amyloid precursor protein, beta-secretase enzyme, and presenilin 1 proteins were analyzed by Western blot analysis. The results showed that EGR1 overexpression increased Aß40 secretion in vitro, possibly through increasing BACE1 expression. Based on these results, EGR1 might be a promising therapeutic target for the AD.

Decreased expression of cell adhesion genes in cancer stem-like cells isolated from primary oral squamous cell carcinomas.

The goal of this study was to isolate cancer stem-like cells marked by high expression of CD44, a putative cancer stem cell marker, from primary oral squamous cell carcinomas and identify distinctive gene expression patterns in these cells. From 1 October 2013 to 4 September 2015, 76 stage III-IV primary oral squamous cell carcinoma of the gingivobuccal sulcus were resected. In all, 13 tumours were analysed by immunohistochemistry to visualise CD44-expressing cells. Expression of CD44 within The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma RNA-sequencing data was also assessed. Seventy resected tumours were dissociated into single cells and stained with antibodies to CD44 as well as CD45 and CD31 (together referred as Lineage/Lin). From 45 of these, CD44+Lin- and CD44-Lin- subpopulations were successfully isolated using fluorescence-activated cell sorting, and good-quality RNA was obtained from 14 such sorted pairs. Libraries from five pairs were sequenced and the results analysed using bioinformatics tools. Reverse transcription quantitative polymerase chain reaction was performed to experimentally validate the differential expression of selected candidate genes identified from the transcriptome sequencing in the same 5 and an additional 9 tumours. CD44 was expressed on the surface of poorly differentiated tumour cells, and within the The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma samples, its messenger RNA levels were higher in tumours compared to normal. Transcriptomics revealed that 102 genes were upregulated and 85 genes were downregulated in CD44+Lin- compared to CD44-Lin- cells in at least 3 of the 5 tumours sequenced. The upregulated genes included those involved in immune regulation, while the downregulated genes were enriched for genes involved in cell adhesion. Decreased expression of PCDH18, MGP, SPARCL1 and KRTDAP was confirmed by reverse transcription quantitative polymerase chain reaction. Lower expression of the cell-cell adhesion molecule PCDH18 correlated with poorer overall survival in the The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma data highlighting it as a potential negative prognostic factor in this cancer.

Pulmonary large cell neuroendocrine carcinoma with adenocarcinoma-like features: napsin A expression and genomic alterations.

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is a highly aggressive malignancy, which was recently found to comprise three major genomic subsets: small cell carcinoma-like, non-small cell carcinoma (predominantly adenocarcinoma)-like, and carcinoid-like. To further characterize adenocarcinoma-like subset, here we analyzed the expression of exocrine marker napsin A, along with TTF-1, in a large series of LCNECs (n=112), and performed detailed clinicopathologic and genomic analysis of napsin A-positive cases. For comparison, we analyzed napsin A expression in other lung neuroendocrine neoplasms (177 carcinoids, 37 small cell carcinomas) and 60 lung adenocarcinomas. We found that napsin A was expressed in 15% of LCNEC (17/112), whereas all carcinoids and small cell carcinomas were consistently negative. Napsin A reactivity in LCNEC was focal in 12/17 cases, and weak or moderate in intensity in all cases, which was significantly lower in the extent and intensity than seen in adenocarcinomas (P<0.0001). The combination of TTF-1-diffuse/napsin A-negative or focal was typical of LCNEC but was rare in adenocarcinoma, and could thus serve as a helpful diagnostic clue. The diagnosis of napsin A-positive LCNECs was confirmed by classic morphology, diffuse labeling for at least one neuroendocrine marker, most consistently synaptophysin, and the lack of distinct adenocarcinoma component. Genomic analysis of 14 napsin A-positive LCNECs revealed the presence of mutations typical of lung adenocarcinoma (KRAS and/or STK11) in 11 cases. In conclusion, LCNECs are unique among lung neuroendocrine neoplasms in that some of these tumors exhibit low-level expression of exocrine marker napsin A, and harbor genomic alterations typical of adenocarcinoma. Despite the apparent close biological relationship, designation of adeno-like LCNEC as a separate entity from adenocarcinoma is supported by their distinctive morphology, typically diffuse expression of neuroendocrine marker(s) and aggressive behavior. Further studies are warranted to assess the clinical utility and optimal method of identifying adenocarcinoma-like and other subsets of LCNEC in routine practice.

Ethanol-induced PGE2 up-regulates Aß production through PKA/CREB signaling pathway.

Ethanol abuse aggravates dementia-associated cognitive defects through the progression of Alzheimer's disease (AD) pathophysiology. Beta-site APP-cleaving enzyme 1 (BACE1) has been considered as a key regulator of AD pathogenesis by controlling amyloid beta peptide (Aß) accumulation. In addition, previous studies reported that endoplasmic reticulum (ER) stress and neuroinflammation have been proposed in ethanol-induced neurodegeneration. Thus, we investigated the role of ER stress and PGE2, a neuroinflammation mediator, in the ethanol-stimulated BACE1 expression and Aß production. Using the human-derived neuroblastoma cell line SK-N-MC, the results show that ethanol up-regulated BACE1 expression in a dose-dependent manner. Ethanol stimulated reactive oxygen species (ROS) production, which induced CHOP expression and eIF2α phosphorylation. PBA (an ER stress inhibitor) attenuated the ethanol-increased cyclooxygenase-2 (COX-2) expression and PGE2 production. By using salubrinal (an eIF2α dephosphorylation inhibitor) or EIF2A siRNA, we found that eIF2α phosphorylation mediated the ethanol-induced COX-2 expression. In addition, COX-2-induced BACE1 up-regulation was abolished by NS-398 (a selective COX-2 inhibitor). And, PF-04418948 (an EP-2 receptor inhibitor) pretreatment reduced ethanol-induced PKA activation and CREB phosphorylation as well as ethanol-stimulated Aß production. Furthermore, 14-22 amide (a PKA inhibitor) pretreatment or CREB1 siRNA transfection suppressed the ethanol-induced BACE1 expression. In conclusion, ethanol-induced eIF2α phosphorylation stimulates COX-2 expression and PGE2 production which induces the BACE1 expression and Aß production via EP-2 receptor-dependent PKA/CREB pathway.

The Utility of Thyroid Transcription Factor 1 (TTF-1), Napsin A, Excision Repair Cross-Complementing 1 (ERCC1), Anaplastic Lymphoma Kinase (ALK) and the Epidermal Growth Factor Receptor (EGFR) Expression in Small Biopsy in Prognosis of Patients with Lung Adenocarcinoma - A Retrograde Single-Center Study from Croatia.

BACKGROUND The present study was carried out in order to evaluate our institutional experience with small biopsy in diagnosis and molecular testing of lung adenocarcinoma. Few specific and predictive markers have been evaluated and correlated with clinicopathologic characteristics and survival in patients with lung adenocarcinoma who received platinum-based chemotherapy. There have not been such reports from Croatia. MATERIAL AND METHODS A total of 142 cases of lung adenocarcinoma were retrospectively investigated in small biopsies for the immunohistochemical expression of TTF-1, napsin A, ERCC1, ALK, and the EGFR mutation by real-time polymerase chain reaction (rtPCR). RESULTS TTF-1, napsin A, and ERCC1 expression was found in 81%, 78%, and 69% of patients, respectively, and the expressions were not significantly associated with subtype. Expression of ALK was found in 4% and EGFR mutation in 10% of patients. Exon 19 deletions were the most common. Longer survival was significantly associated with TTF-1 positivity (p=0.007) and napsin A positivity (p=0.026). Higher relative risk of death significantly correlated with positive expression of ERCC1 (p=0.041). CONCLUSIONS Positive TTF-1 and napsin A expressions in lung adenocarcinoma tissues were useful diagnostic and favorable prognostic parameters. Positive ERCC1 expression was identified as a negative prognostic marker in patients treated with platinum-based chemotherapy. The percentages of EGFR and ALK mutations corresponded to those in previously published reports for Caucasians.

Neurohormetic responses of quercetin and rutin in a cell line over-expressing the amyloid precursor protein (APPswe cells).

BACKGROUND: Plant secondary metabolites may induce adaptive cellular stress-responses in a variety of cells including neurons at the sub-toxic doses ingested by humans. Such 'neurohormesis' phenomenon, activated by flavonoids such as quercetin or rutin, may involve cell responses driven by modulation of signaling pathways which are responsible for its neuroprotective effects. PURPOSE: We attempt to explore the molecular mechanisms involved in the neurohormetic responses to quercetin and rutin exposure, in a SH-SY5Y cell line which stably overexpresses the amyloid precursor protein (APP) Swedish mutation, based on a biphasic concentration-response relationship for cell viability. METHODS: We examined the impact of both natural compounds, at concentrations in its hormetic range on the following cell parameters: chymotrypsin-like activity of the proteasome system; PARP-1 protein levels and expression and caspase activation; APP processing; and the main endogenous antioxidant enzymes. RESULTS: Proteasome activities following quercetin or rutin treatment were significantly augmented in comparison with non-treated cells. Activity of caspase-3 was significantly attenuated by treatment with quercetin or rutin. Modest increased levels of PARP-1 protein and mRNA transcripts were observed in relation to the mild increase of proteasome activity. Significant reductions of the full-length APP and sAPP protein and APP mRNA levels were related to significant enhancements of α-secretase ADAM-10 protein and mRNA transcripts and significant increases of BACE processing in cells exposed to rutin. Furthermore, quercetin or rutin treatment displayed an overall increase of the four antioxidant enzymes. CONCLUSIONS: The upregulation of the proteasome activity observed upon quercetin or rutin treatment could be afforded by a mild increased of PARP-1. Consequently, targeting the proteasome by quercetin or rutin to enhance its activity in a mild manner could avoid caspase activation. Moreover, it is likely that APP processing of cells upon rutin treatment is mostly driven by the non-amyloidogenic pathway leading to a putative reduction of ßA production. Overall induction of endogenous antioxidant enzymes under quercetin or rutin treatments of APPswe cells might modulate its proteasome activity. We might conclude that quercetin and rutin might exert a neurohormetic cell response affecting various signaling pathways and molecular networks associated with modulation of proteasome function.

Immunohistochemical Detection of Pax8 and Napsin A in Canine Thyroid Tumours: Comparison with Thyroglobulin, Calcitonin and Thyroid Transcription Factor 1.

Expression of thyroid transcription factor (TTF)-1 corroborates a thyroid origin of neoplasms. Thyroglobulin and calcitonin immunohistochemistry (IHC) can distinguish between a follicular and C-cell origin of thyroid tumours, respectively. Pax8 (expressed by normal canine thyroid follicular cells) and napsin A (expressed mainly by C-cells) labelling was compared with labelling for TTF-1, thyroglobulin and calcitonin in 114 canine proliferative thyroid lesions. All 81 follicular tumours expressed thyroglobulin and were negative for calcitonin; 79/81 (98%) of these tumours expressed TTF-1 and Pax8 and 60/81 (74%) expressed napsin A. All 25 C-cell lesions expressed calcitonin and were negative for expression of thyroglobulin; 22 (88%) were positive for TTF-1, 13 (57%) for Pax8 and 24/24 for napsin A. Six mixed follicular-medullary carcinomas expressed all five markers. Both carcinosarcomas expressed TTF-1 and napsin A, and one each of these tumours expressed thyroglobulin, calcitonin or Pax8. Pax8 expression was also detected in epididymal cells, endometrial cells and vas deferens epithelium, in Sertoli-like ovarian cells, and in some cases of ovarian adenoma, pancreatic carcinoma, renal cell carcinoma and Sertoli cell tumour. Napsin A was also detected in adrenocortical cells, ovarian granulosa cells, epididymal and endometrial cells, as well as in some renal cell carcinomas, pulmonary adenocarcinomas and Sertoli cell tumours. In summary, Pax8 was as sensitive as TTF-1 and slightly less sensitive than thyroglobulin for identification of follicular tumours, but had low sensitivity for C-cell tumours. Napsin A was as sensitive as calcitonin for C-cell neoplasms, but was less sensitive than thyroglobulin for follicular neoplasms. Thus, these markers are sensitive and, except for renal cell carcinoma (for Pax8, napsin A) and pulmonary adenocarcinoma (for napsin A), are specific thyroid tumour markers.

Aberrant Expression of Napsin A in Breast Carcinoma With Apocrine Features.

An incidental finding of napsin A-positive breast carcinoma with apocrine features during workup for metastatic cancer in an axillary lymph node led to our investigation of the incidence of napsin A expression in breast carcinomas, focusing on those with apocrine features. We included 97 cases of breast carcinomas and performed immunohistochemistry with napsin A, GATA-3, thyroid transcription factor-1, and GCDFP-15. There was a statistically significant difference between apocrine and nonapocrine cases with respect to polyclonal napsin A H-scores (P < .00152), monoclonal napsin A H-scores (P < .00631), GATA-3 H-scores (P < .00029), and GCDFP-15 H-scores (P < .00251). Of the 49 cases of apocrine carcinoma, monoclonal napsin A antibody was positive in 66.7% of cases, including in 7 (14.6%) that showed 3+ staining. The majority of nonapocrine cases were negative (62.5%) or weakly (1+) positive (29.2%), with none exhibiting 3+ strength. It is important for pathologists to be aware that breast carcinomas with apocrine features can express napsin A.

Bisecting GlcNAc modification stabilizes BACE1 protein under oxidative stress conditions.

ß-Site amyloid precursor protein-cleaving enzyme-1 (BACE1) is a protease essential for amyloid-ß (Aß) production in Alzheimer's disease (AD). BACE1 protein is known to be up-regulated by oxidative stress-inducing stimuli but the mechanism for this up-regulation still needs to be clarified. We have recently found that BACE1 is modified with bisecting N-acetylglucosamine (GlcNAc) by N-acetylglucosaminyltransferase-III (GnT-III, encoded by the Mgat3 gene) and that GnT-III deficiency reduces Aß-plaque formation in the brain by accelerating lysosomal degradation of BACE1. Therefore, we hypothesized that bisecting GlcNAc would stabilize BACE1 protein on oxidative stress. In the present study, we first show that Aß deposition in the mouse brain induces oxidative stress, together with an increase in levels of BACE1 and bisecting GlcNAc. Furthermore, prooxidant treatment induces expression of BACE1 protein in wild-type mouse embryonic fibroblasts (MEFs), whereas it reduces BACE1 protein in GnT-III (Mgat3) knock-out MEFs by accelerating lysosomal degradation of BACE1. We purified BACE1 from Neuro2A cells and performed LC/ESI/MS analysis for BACE1-derived glycopeptides and mapped bisecting GlcNAc-modified sites on BACE1. Point mutations at two N-glycosylation sites (Asn(153) and Asn(223)) abolish the bisecting GlcNAc modification on BACE1. These mutations almost cancelled the enhanced BACE1 degradation seen in Mgat3(-/-) MEFs, indicating that bisecting GlcNAc on BACE1 indeed regulates its degradation. Finally, we show that traumatic brain injury-induced BACE1 up-regulation is significantly suppressed in the Mgat3(-/-) brain. These results highlight the role of bisecting GlcNAc in oxidative stress-induced BACE1 expression and offer a novel glycan-targeted strategy for suppressing Aß generation.

Downregulated miR-29c correlates with increased BACE1 expression in sporadic Alzheimer's disease.

BACKGROUND: Beta-site Amyloid precursor protein Cleaving Enzyme 1 (BACE1) is conceived as a potential target for therapies against Alzheimer disease (AD) which is characterized by the accumulation of plaques formed of short ß-amyloid (APPß) peptides. Recently, such microRNAs, as miR-29a, miR-29b-1 have been shown to correlate with abnormally high levels of BACE1 and APPß in sporadic AD. METHODS: In order to confirm whether miR-29c correlates with the BACE1 upregulation in sporadic AD, we firstly evaluated the expression of miR-29c and BACE1, the APPß accumulation in sporadic AD brain tissues and analyzed the correlation of miR-29c with BACE1. Then we determined the regulation of miR-29c in human heuroblastoma SH-SY5Y cells on the BACE1 expression and APPß accumulation. And finally we determined the targeting to 3' UTR of BACE1 by miR-29c by a luciferase reporter. RESULTS: It was demonstrated that miR-29c was downregulated in sporadic AD brains, in an association with an upregulation of BACE1 in both mRNA and protein level of BACE1, and also an elevated APPß accumulation. And the manipulated high level of miR-29c with miR-29c mimics transfection significantly reduced the protein level of BACE1 and APPß accumulation in human neuroblastoma SH-SY5Y cells. Further luciferase reporter assay demonstrated that miR-29c targets the 3' UTR of BACE1 and downregulated the BACE1 in HEK293 cells. CONCLUSION: Present study indicated that miR-29c was downregulated in sporadic AD brains, and it targeted the 3' UTR of BACE1, reduced the BACE1 expression, and downregulated the APPß accumulation in vitro.

Upregulation of SET expression by BACE1 and its implications in Down syndrome.

Down syndrome (DS) is one of the most common genetic diseases. Patients with DS display growth delay and intellectual disabilities and develop Alzheimer's disease (AD) neuropathology after middle age, including neuritic plaques and neurofibrillary tangles. Beta-site amyloid ß precursor protein (APP) cleaving enzyme 1 (BACE1), essential for Aß production and neuritic plaque formation, is elevated in DS patients. However, its homolog, ß-site APP cleaving enzyme 2 (BACE2), functions as θ-secretase and plays a differential role in plaque formation. In this study, by using Two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (2D SDS-PAGE) and LC-MS/MS proteomic profiling analysis, we found that the SET oncogene protein (SET) expression was associated with BACE1 but not BACE2. SET protein was increased in BACE1 overexpressing cells and was markedly reduced in the BACE1 knockout mice. We found that the overexpression of BACE1 or SET significantly inhibited cell proliferation. Moreover, knockdown of SET in BACE1 overexpression cells significantly rescued BACE1-induced cell growth suppression. Furthermore, both BACE1 and SET protein levels were increased in Down syndrome patients. It suggests that BACE1 overexpression-induced SET upregulation may contribute to growth delay and cognitive impairment in DS patients. Our work provides a new insight that BACE1 overexpression not only promotes neuritic plaque formation but may also potentiate neurodegeneration mediated by SET elevation in Alzheimer-associated dementia in DS.

Napsin A is a specific marker for ovarian clear cell adenocarcinoma.

Ovarian clear cell adenocarcinoma has a relatively poor prognosis among the ovarian cancer subtypes because of its high chemoresistance. Differential diagnosis of clear cell adenocarcinoma from other ovarian surface epithelial tumors is important for its treatment. Napsin A is a known diagnostic marker for lung adenocarcinoma, and expression of napsin A is reported in a certain portion of thyroid and renal carcinomas. However, napsin A expression in ovarian surface epithelial tumors has not previously been examined. In this study, immunohistochemical analysis revealed that in 71 of 86 ovarian clear cell adenocarcinoma patients (83%) and all of the 13 patients with ovarian clear cell adenofibroma, positive napsin A staining was evident. No expression was observed in 30 serous adenocarcinomas, 11 serous adenomas or borderline tumors, 19 endometrioid adenocarcinomas, 22 mucinous adenomas or borderline tumors, 10 mucinous adenocarcinomas, or 3 yolk sac tumors of the ovary. Furthermore, expression of napsin A was not observed in the normal surface epithelium of the ovary, epithelia of the fallopian tubes, squamous epithelium, endocervical epithelium, or the endometrium of the uterus. Therefore, we propose that napsin A is another sensitive and specific marker for distinguishing ovarian clear cell tumors (especially adenocarcinomas) from other ovarian tumors.

The lung-restricted marker napsin A is highly expressed in clear cell carcinomas of the ovary.

OBJECTIVES: We recently observed expression of the "lung" marker napsin A in ovarian clear cell carcinomas and therefore sought to determine the extent of napsin A expression in a subset of ovarian neoplasms. METHODS: We identified an archival series of ovarian clear cell carcinomas (n = 36), serous borderline tumors (n = 21), high-grade serous carcinomas (n = 37), and endometrioid adenocarcinomas (n = 29). Using standard immunohistochemical techniques on whole sections of formalin-fixed, paraffin-embedded specimens, we employed a panel of antibodies: napsin A (IP64), estrogen receptor (SP1), WT-1 (6F-H2), PAX-8 (BC12), and TTF-1 (SPT24). RESULTS: Thirty-six of 36 clear cell carcinomas showed napsin A expression, typically in a uniform pattern. None of the serous borderline tumors or high-grade serous carcinomas manifested napsin A expression. Napsin A was expressed in three (10%) of 29 endometrioid adenocarcinomas, generally in a focal pattern. CONCLUSIONS: Our study showed that napsin A is an extremely sensitive (100%) marker of ovarian clear cell carcinomas and exhibits very high specificity (100%) in distinguishing clear cell carcinomas from high-grade serous carcinomas and serous borderline tumors and 90% specificity in discriminating clear cell carcinomas from endometrioid carcinomas.

The effects of Betula platyphylla bark on amyloid beta-induced learning and memory impairment in mice.

Alzheimer's disease (AD) is closely associated with amyloid ß (Aß)-induced neurotoxicity and oxidative stress in the brain. Betula platyphylla, which has been used to treat various oxidative-stressed related diseases, has recently received attention for its preventive activity on age-related neurodegenerative diseases. In this study, we attempted to investigate the effects of B. platyphylla bark (BPB-316) on Aß(1-42)-induced neurotoxicity and memory impairment. Oral treatment using BPB-316 significantly attenuated Aß-induced memory impairment which was evaluated by behavioral tests including the passive avoidance, Y-maze and Morris water maze test. BPB-316 also inhibited the elevation of ß-secretase activity accompanying the reduced Aß(1-42) levels in the hippocampus of the brain. Furthermore, BPB-316 significantly decreased the acetylcholinesterase activity and increased the glutathione content in the hippocampus. In addition, we confirmed that the expression of both cAMP responsive element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) in the hippocampus of Aß(1-42)-injected mice were markedly upregulated by the treatment of BPB-316. Our data suggest that the extracts of B. platyphylla bark might be a potential therapeutic agent against AD.

ΔNp63, CK5/6, TTF-1 and napsin A, a reliable panel to subtype non-small cell lung cancer in biopsy specimens.

Histopathological subtyping of nonsmall cell lung cancer (NSCLC) is currently important in selecting specific therapeutic agents. It can be challenging in distinguishing poorly differentiated lung adenocarcinoma (AC) from squamous cell carcinoma (SCC) on small biopsy samples. This study was aimed to evaluate the utility of a panel of immunohistochemical markers consisting of ΔNp63 (p40), cytokeratins (CK) 5/6, thyroid transcription factor-1 (TTF-1) and napsin A (novel aspartic proteinase of the pepsin family) in subtyping poorly differentiated NSCLC. Forty-eight cases of NSCLC that could not be further classified by examination of hematoxylin-eosin (H&E)-stained slides on biopsy and had subsequent resection specimens were selected. Subtyping of the tumor was based on the resection specimen using the World Health Organization criteria. ΔNp63 was expressed in all 16 SCCs (100%), and was negative in all ACs and LCCs. CK5/6 was positive in 13 of 16 SCCs (81%), and was negative in all ACs and LCCs. TTF-1 was positive in 20 of 25 ACs (80%) and 3 of 7 LCCs (43%), but none of 16 SCCs. Napsin A was positive in 16 of 25 ACs (64%) and was negative in all SCCs and LCCs. Our study shows that a panel including ΔNp63, CK5/6, TTF-1, and napsin A allows correct subclassification of 39 of 48 cases of NSCLC on biopsy and may contribute to refine lung cancer classification in biopsy specimens, remarkably reducing the NSCLC-NOS (not otherwise specified) diagnostic category.