TRPS1: a highly sensitive and specific marker for breast carcinoma, especially for triple-negative breast cancer

Currently there is no highly specific and sensitive marker to identify breast cancer-the most common malignancy in women. Breast cancer can be categorized as estrogen receptor (ER)/progesterone receptor (PR)-positive luminal, human epidermal growth factor receptor 2 (HER2)-positive, or triple-negative breast cancer (TNBC) types based on the expression of ER, PR, and HER2. Although GATA3 is the most widely used tumor marker at present to determine the breast origin, which has been shown to be an excellent marker for ER-positive and low-grade breast cancer, but it does not work well for TNBC with sensitivity as low as <20% in metaplastic breast carcinoma. In the current study, through TCGA data mining we identified trichorhinophalangeal syndrome type 1 (TRPS1) as a specific gene for breast carcinoma across 31 solid tumor types. Moreover, high mRNA level of TRPS1 was found in all four subtypes of breast carcinoma including ER/PR-positive luminal A and B types, HER2-positive type, and basal-type/TNBC. We then analyzed TRPS1 expression in 479 cases of various types of breast cancer using immunochemistry staining, and found that TRPS1 and GATA3 had comparable positive expression in ER-positive (98% vs. 95%) and HER2-positive (87% vs. 88%) breast carcinomas. However, TRPS1 which was highly expressed in TNBC, was significantly higher than GATA3 expression in metaplastic (86% vs. 21%) and nonmetaplastic (86% vs. 51%) TNBC. In addition, TRPS1 expression was evaluated in 1234 cases of solid tumor from different organs. In contrast to the high expression of GATA3 in urothelial carcinoma, TRPS1 showed no or little expression in urothelial carcinomas or in other tumor types including lung adenocarcinoma, pancreatic adenocarcinoma, colon and gastric adenocarcinoma, renal cell carcinoma, melanoma, and ovarian carcinoma. These findings suggest that TRPS1 is a highly sensitive and specific marker for breast carcinoma and can be used as a great diagnostic tool, especially for TNBC.

Transition From a Standard to a Hybrid On-Site and Remote Anatomic Pathology Training Model During the Coronavirus Disease 2019 (COVID-19) Pandemic

CONTEXT.—

As teaching hospitals institute social distancing and defer nonemergent procedures to cope with the coronavirus disease 2019 pandemic, the need for daily on-site presence, unless necessary, has been reduced for all medical staff, including trainees. Pathology training programs must adapt to these changes to ensure overall safety without significantly compromising training and the educational mission of the institution.

OBJECTIVE.—

To describe the hybrid on-site and remote anatomic pathology training model in response to the coronavirus disease 2019 pandemic that was implemented in our pathology department and report the clinical fellows' responses to the survey about their experiences.

DESIGN.—

The hybrid model was implemented March 25, 2020. Fellows alternate weekly between working on site and working remotely. On site, fellows wear personal protective equipment and maintain social distancing. Remotely, fellows use digital pathology to review cases and supplement with online educational activities. Virtual "coffee breaks," meditation, and exercise are part of the curriculum. Online platforms, including WebEx, Google Classroom, and Canvas, are used to continue educational activities. The survey was open May 19 through June 8, 2020.

RESULTS.—

Twenty-eight of the 29 clinical fellows (96%) responded. Many of the respondents indicated substantial increase in their skill with using digital pathology and online platforms during the pandemic. The top most helpful resources were the United States and Canadian Academy of Pathology interactive microscopy courses (found very or somewhat helpful by 22 of 23 clinical fellows; 96%), ExpertPath (19 of 23; 82%), the College of American Pathologists virtual learning series (18 of 23; 78%), the World Health Organization Blue Books (16 of 23; 70%), the American Society of Cytopathology webinars (14 of 23; 61%), and our institutional digital slide collection (12 of 23; 52%).

CONCLUSIONS.—

Hybrid on-site and remote training can maximize anatomic pathology learning opportunities while maintaining the safety of trainees, hospital personnel, and the community.

Solid Tumor Metastases to the Pancreas Diagnosed Using Fine-Needle Aspiration

OBJECTIVES

Solid tumor metastases to the pancreas are rare, and only limited literature on the topic is available. In this retrospective study, we reviewed 107 cases of solid tumor metastases to the pancreas diagnosed by fine-needle aspiration (FNA) from 2005 to 2019.

METHODS

Information including the patients' clinical histories, radiologic and pathologic findings, treatments, and follow-up were collected.

RESULTS

The mean age of the patients was 62.4 years. The mean tumor size was 2.64 cm with even distribution throughout the pancreas (head, neck and body, and tail). The most common primary site was the kidney, followed by the lung, skin, and breast and the gynecologic, gastrointestinal, and genitourinary tracts. The most common tumor type was carcinoma, followed by melanoma and sarcoma. In comparison to patients with nonkidney primary cancers, those with primary renal cell carcinoma had a longer median interval between primary diagnosis and metastasis (8.5 vs 4.0 years; P < .01), less often had metastasis outside the pancreas (38% vs 74%; P < .01), and had a significantly longer 5-year survival rate (65.7% vs 24.8%; P < .01).

CONCLUSIONS

FNA plays a crucial role in diagnosing metastases to the pancreas. Metastases originating from kidney and nonkidney primary tumors have distinct clinicopathologic features and prognoses.

Functional microRNA screening for dietary vitamin E regulation of abdominal fat deposition in broilers

1. Functional microRNA (miRNA) screening for abdominal fat tissue with different dietary vitamin E (VE) levels was performed to reveal miRNAs, genes and metabolic pathways involved in abdominal fat deposition in broilers. 2. A total of 240, one-day-old healthy female chicks were randomly allocated into five dietary treatments containing either 0, 20, 50, 75 or 100 IU DL-α-tocopherol acetate. The sequencing of miRNAs from abdominal fat tissues was performed. The target genes of miRNAs were predicted and enrichment analysis for these genes was performed. Diets supplemented with 50 IU VE significantly diminished abdominal fat deposition in broilers at day 35 of age. 3. A total of 29 miRNAs were differentially expressed between control and 50 IU VE treatment. Ten of the 23 target genes were enriched in four signalling pathways: tight junction, SNARE interactions in vesicular transport, regulation of autophagy and proteasome. 4. This study identified miRNA, target genes and pathways in dietary VE treatment for broilers, providing new insights into the miRNA regulation of abdominal fat deposition in broilers.

Insulinoma-associated protein 1 immunostaining for various types of neuroendocrine tumors on FNA smears

BACKGROUND

Insulinoma-associated protein 1 (INSM1) has recently emerged as a reliable nuclear immunostaining marker for detecting neuroendocrine tumors (NETs) in paraffin-embedded surgical samples and cytologic cell blocks, but the reliability of INSM1 staining on cytologic smears is understudied. This study investigated the performance of INSM1 staining on cytologic smears for the detection of various NETs in comparison with chromogranin (CG) and synaptophysin (SYN).

METHODS

INSM1, CG, and SYN were stained on cytologic smears of 70 NETs, including 20 pancreatic NETs, 10 lung carcinoid tumors, 11 small cell lung carcinomas (SCLCs), 10 medullary thyroid carcinomas, 10 Merkel cell carcinomas, 4 thymic atypical carcinoid tumors, and 5 olfactory neuroblastomas. The detection rate, the percentage of positive cells, and the staining intensity were recorded.

RESULTS

The overall detection rate of INSM1 (94%) was higher than the rates of CG (79%) and SYN (89%). The detection rate of INSM1 was higher than the rates of CG and SYN in SCLC, Merkel cell carcinoma, and olfactory neuroblastoma; higher than the rate of CG and equal to the rate of SYN in pancreatic NETs and medullary thyroid carcinoma; equal to the rate of CG and higher than the rate of SYN in thymic atypical carcinoid tumors; and equal to the rate of CG and lower than the rate of SYN in lung carcinoid tumors. INSM1 staining was easier to interpret than CG and SYN staining, especially in high-grade NETs.

CONCLUSIONS

INSM1 can be reliably stained on cytologic smears and outperforms CG and SYN in the verification of clinically or radiologically suspected NETs.

Sclerosing epithelioid fibrosarcoma: cytologic characterization with histologic, immunohistologic, molecular, and clinical correlation of 8 cases

INTRODUCTION

Sclerosing epithelioid fibrosarcoma (SEF) is an uncommon malignant fibroblastic neoplasm. The diagnosis is typically made on core needle biopsy or resection specimens. Cytomorphologic characterization of SEF has been limited to rare case reports in the literature. The goal of this study was to review a series of cases of SEF and to determine the feasibility of cytologic diagnosis of this rare tumor.

MATERIAL AND METHODS

Eight SEF cases from 2009 to 2019 were identified in a retrospective review of 3 participating institutions. Cytomorphologic and corresponding histologic, immunophenotypic, molecular, and clinical data were examined and described.

RESULTS

Patients were of median age 41 years old at diagnosis with a median follow-up of 35.5 months. These tumors, with a median greatest dimension of 13.4 cm, were located in the lower extremities, abdomen, retroperitoneum, head, groin, sacrum, and lung. The tumor cells ranged from small round, medium-sized ovoid/short spindle, to epithelioid/plasmacytoid cells. A sclerotic, fibrous to myxoid stroma was seen. Most samples revealed low-grade cytology. Two cases showed tumor necrosis. Only 3 cases with cell block/positive MUC4 immunostain were diagnostic. Corresponding molecular testing for EWSR1 gene rearrangement and/or EWSR1-CREB3L1 fusion were positive in 5 of 8 cases on biopsy or surgical samples. An additional case was positive for FUS-CREB3L2 fusion.

CONCLUSIONS

Diagnosis of SEF based solely upon cytologic features remains challenging. Epithelioid or plasmacytoid morphology mimics common malignancies. A supportive clinical history, MUC4 immunohistochemistry, and characteristic molecular result should be used to aid the diagnosis.

Utility of subcategorization of atypia of undetermined significance/follicular lesion of undetermined significance category in ultrasound-guided thyroid fine-needle aspiration in a large referral cancer center

INTRODUCTION

Subclassification of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) is encouraged in the Bethesda System. In our practice, we subclassified AUS/FLUS into 3 subcategories: atypical follicular cells of undetermined significance (ACUS) for cases with cytologic atypia; follicular lesion (FL) for cellular cases with follicular cells with-minimal or no atypia, arranged in a macro- and micro-follicular pattern with scant colloid; and indeterminate follicular lesion, favor benign (IFL-FB) for cases with few clusters of follicular cells without atypia associated with minimal or no colloid. The objective of our study was to evaluate the prevalence, clinical management, and risk of malignancy for each subcategory.

MATERIALS AND METHODS

We retrospectively identified ultrasound-guided fine-needle aspiration (US-FNA) of thyroid cases that were subcategorized as ACUS, IFL-FB, and FL at our-institution during 2014-2016. The results of US-FNA were correlated with clinical outcome in the subsequent 2 years including repeat US-FNA, thyroid surgery, and clinical/imaging follow-up.

RESULTS

Of 3207 thyroid US-FNA cases, 718 (22.4%) cases were included in the study. Of these 718 cases, 104 (14.5%) were subcategorized as ACUS, 166 (23.1%) as FL, and 448 (62.4%) as IFL-FB. The surgery rate was 39.4% (41 of 104) for ACUS, 13.6% (61 of 448) for IFL-FB, and 27.1% (45 of 166) for FL. The risk of malignancy (ROM) was 25% (26 of 104) for ACUS, and 2.9% (13 of 448) for IFL-FB, 6.0% (10 of 166) for FL. The surgery rate and ROM was significantly higher for ACUS in comparison to IFL-FB (P < 0.05) and FL (P < 0.05).

CONCLUSIONS

Subclassification of AUS/FLUS into 3 groups based on cytopathologic findings alone not only improved the triage of patients for subsequent clinical management but also effectively stratified the risk of malignancy.

Utility of NKX3.1 Immunostaining in the Detection of Metastatic Prostatic Carcinoma on Fine-Needle Aspiration Smears

OBJECTIVES

NK3 homeobox 1 (NKX3.1) has been increasingly used to diagnose metastatic prostatic carcinoma in histologic samples. However, its utility and reliability in cytologic direct smears have not been studied.

METHODS

A total of 59 fine-needle aspiration (FNA) cases with a definitive diagnosis of metastatic carcinoma from the prostate were included. The cases were grouped based on different Gleason score in their corresponding primary tumors and morphologic variants. For each case, tumor cells were immunostained with NKX3.1, prostate-specific antigen (PSA), and prostatic acid phosphatase (PAP) on cell-transferred smears.

RESULTS

NKX3.1 was strongly and diffusely positive in all 40 metastatic prostatic adenocarcinomas, including those with ductal features, but negative for the 19 small cell carcinoma (SmCC) cases. NKX3.1 had a better detection rate than PSA (13/50, 26%) and PAP (0/47, 0%).

CONCLUSIONS

NKX3.1 immunostaining on FNA smears is highly reliable for detecting metastatic prostatic carcinomas of conventional and ductal types but not for SmCC.

Cytologic Evaluation of Positron Emission Tomography-Computed Tomography-Positive Lymph Nodes Sampled by Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration: Experience at a Large Cancer Center

CONTEXT.—

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is routinely used to evaluate mediastinal lymph nodes (LNs), especially for cancer staging. There are limited large studies evaluating the cytologic, radiologic, and clinical features of ¹⁸F-fluorodeoxy glucose positron emission tomography-computed tomography-positive (PET-CT+) LNs.

OBJECTIVE.—

To compare cytologic, radiologic, and clinical features of PET-CT+, cytology-malignant (PET-CT+/Cyto+) and PET-CT+, cytology-benign (PET-CT+/Cyto-) LNs.

DESIGN.—

The pathology database was searched for cases of mediastinal LNs obtained by EBUS-TBNA from January 1, 2015 to December 31, 2015. The cytologic, radiologic, and clinical features were collected for all PET-CT+ LNs.

RESULTS.—

Of 2267 mediastinal LNs obtained by EBUS-TBNA during this period, 577 LNs met the criteria. Of the latter, 263 (46%) were PET-CT+/Cyto+ and 314 (54%) were PET-CT+/Cyto-. All of the patients with PET-CT+/Cyto+ results had a prior or concurrent diagnosis of malignancy as compared to 89% of patients with PET-CT+/Cyto- results. Of the 224 patients with PET-CT+/Cyto+ LNs, 177 (79%) had metastases from lung primary, 43 (19%) had metastases from nonlung primaries, and 7 (3%) had lymphoma. Average LN size was larger in the PET-CT+/Cyto+ group than in the PET-CT+/Cyto- group (14.6 mm versus 9.58 mm), and mean standardized uptake value in PET-CT+/Cyto+ LNs was higher than that of PET-CT+/Cyto- LNs (10.05 versus 5.99). Significant cytologic findings in PET-CT+/Cyto- cases were necrosis and granulomatous inflammation, including 3 cases with fungal organisms.

CONCLUSIONS.—

PET-CT positivity alone was nonspecific for malignancy and insufficient to guide management of patients with mediastinal adenopathy, but specificity could be improved when combined with LN size and standardized uptake value.

[Associations between milk intake at breakfast and nutritional status of students attending the Nutrition Improvement Program for Rural Compulsory Education Students in 2016]

Objective: To investigate the association between milk intake at breakfast and nutritional status of students attending the Nutrition Improvement Program for Rural Compulsory Education Students (NIPRCES) in 2016, and to provide basic data for improving the nutritional status of the poor rural pupils. Methods: Using the multi-stage stratified random cluster sampling method, 22 315 students from grade three to nine from primary and junior high schools were randomly selected from the 50 key counties under the monitor programs, in 22 provinces of NNIPRCS. Questionnaire was used. Among all the students, with equal number of genders, morning fasting height and weight were measured by trained investigators. Status of nutrition was classified as malnutrition, normal, overweight/obesity, by age-specific height and BMI. Multivariate linear and logistic regression methods were used to analyze the relationship between milk consumption and the status of nutrition of the students. Results: Only 31.4% of the students that were on the monitoring programs would drink milk at breakfast. Proportions of milk intake at breakfast were higher in students from the western regions, in lower grades and in girls (P<0.05). The proportions of malnutrition and overweight/obesity were 11.0% and 10.0% respectively. After controlling factors as gender, age, ethnicity, region of residency and types of parental employment, students who drank milk at breakfast showed an average height of 0.4 cm taller than those who did not drink milk (P=0.001). However, no significant relationships were noticed between milk intake at breakfast and weight, malnutrition or overweight/obesity. Conclusion: Milk intake at breakfast seemed associated with the height of the students under study, suggesting that this program can be promoted, especially in students from the poor rural areas.

[Nasal endoscopic treatment in one case of infratemporal fossa hydatid invaded the orbit and skullbase]

PATIENT

male, 43 years old, Tibetan, married. Chief complaint: visual impairment of the left eye for one month. No significant abnormalities observed in nasal endoscopy. Sinus CT: the 47 mm×44 mm cystic low density shadows can be seen in the left infratemporal fossa, which is separated inside, and parts of the lesions have invaded into the orbit and skull base.

DIAGNOSIS

the left infratemporal fossa hydatid invaded the orbit and skull base. Under the guidance of general anesthesia navigation, the patient underwent sinusotomy on the left infratemporal fossa and the left eyesight recovered after operation. CT examination showed that the left temporal lobe tumor has been cleared.

[One case of the infratemporal fossa hydatid invading maxillary sinus]

Summary Male, 43 years old, Tibetan. Main reason: left eyesight impaired for one month. Nasal sinus CT: the 47 mm×44 mm cystic low density shadows can be seen in the left infratemporal fossa, the maxillary sinus cavity reduced under the pressurebase. The patient had the internal and external nasal endoscopic sinus resection of the left fossa.The patient's left eye sight recovered after the operation.Two weeks after the operation, the sinus was re-examined for CT, showing that the left inferior fossa was removed, but there was no significant difference in the maxillary sinus structure. Sixteen months after the operation, the CT showed that the left maxillary sinus is back to normal after absorbing the bone tissue.

Arterial spin labelling MRI for detecting pseudocapsule defects and predicting renal capsule invasion in renal cell carcinoma

AIM

To evaluate prospectively the performance of combining morphological and arterial spin labelling (ASL) magnetic resonance imaging (MRI) for detecting pseudocapsule defects in renal cell carcinoma (RCC), and to predict renal capsule invasion confirmed histopathologically.

MATERIALS AND METHODS

Twenty consecutive patients with suspicious renal tumours underwent MRI. Renal ASL imaging was performed and renal blood flow was measured quantitatively. The diagnostic performance of T2-weighted images alone, and a combination of T2-weighted and ASL images for predicting renal capsule invasion were assessed.

RESULTS

Twenty renal lesions were evaluated in 20 patients. All lesions were clear cell RCCs (ccRCCs) confirmed at post-surgical histopathology. Fifteen ccRCCs showed pseudocapsule defects on T2-weighted images, of which 12 cases showed existing blood flow in defect areas on perfusion images. To predict renal capsule invasion, the sensitivity, specificity, positive predictive value, and negative predictive value were 100%, 71.4%, 86.7%, 100%, respectively, for T2-weighted images alone, and 92.3%, 100%, 100%, 87.5%, respectively, for the combination of T2-weighted and ASL images.

CONCLUSION

ASL images can reflect the perfusion of pseudocapsule defects and as such, the combination of T2-weighted and ASL images produces promising diagnostic accuracy for predicting renal capsule invasion.

[Study on breakfast consumption of children aged from 6-17 in China in 2010-2012]

Objective: To investigate breakfast status and influencing factors among children aged 6-17 in China in 2010-2012. Methods: Data were collected from China National Nutrition and Health Surveillance in 2010-2012. By using multi-stage stratified sampling and population proportional stratified random sampling method, the research objects were 29 393 children, who aged 6 to 17 y from 150 sites in 31 provinces in mainland China. The information of breakfast frequency and the numbers of breakfast dinning out (in restaurant and at schools) in the past week with seven days were collected by questionnaire; and compared by different ages, genders and areas. Results: During the past week, 91.1% (26 776/29 393) of the children aged 6 to 17 y had their breakfast daily, and 94.6% (13 457/14 221) of children aged 6 to 11 y was higher than 87.8% (13 319/15 172) of children aged 12 to 17 y, the highest proportion of the children never eat breakfast (0 time in the past week) found in poor rural areas was 3.6% (189/5 261), the ratio of big cities, small-medium cities and normal rural areas was 1.1% (77/7 104), 0.6% (51/8 361), and 0.6% (54/8 667), respectively (P<0.001). The rate of boys and girls ate their breakfast daily in the past week were 91.3% (13 481/14 761), and 90.9% (13 295/14 632), respectively (P>0.05). Totally 42.2% (12 398/29 393) of children ate breakfast outside-home (the restaurant and the school) in the past week, the percentage of children aged 12 to 17 y and poor rural areas was higher, 50.9% (7 722/15 172), and 52.4% (2 756/5 261), respectively (P<0.001). 42.1% (6 208/14 761) boys and 42.3% (6 190/14 632) girls ate their breakfast outside-home (P>0.05). The place of most school-age children eat outside-home was school, the ratio was 32.2% (9 477/29 393). Conclusion: It was common for school-aged children in China to skip breakfast during their daily lives, especially in poor rural areas and older children, lots of school-aged children ate breakfast outside-home, and most of them ate breakfast in school.

Enhanced SOCS3 in osteoarthiritis may limit both proliferation and inflammation

Osteoarthritis (OA) is a degenerative joint disease that is characterized by localized inflammatory and secondary proliferative changes. Suppressor of cytokine signaling 3 (SOCS3) is elevated during OA development. We investigated the effects of this protein on human chondrocyte survival in OA and the inflammatory response together with the mechanisms of these effects. Small interfering RNA (siRNA) was used to knock down the expression of SOCS3 in interleukin(IL)-1β-induced primary human osteoarthritic chondrocytes. We found that siRNA-mediated SOCS3 knock-down in human osteoarthritic chondrocytes increased production of IL-1β-induced prostaglandin E₂, cell growth, transcript level and nuclear translocation of cyclin D1. Silencing of SOCS3 resulted in altered expression of nuclear factor-kappa-B (NF-κB) and cyclooxygenase (COX2). Our findings indicate that enhanced SOCS3 could have contradictory influences on OA development. SOCS3 might protect damaged joints by its anti-inflammatory effect and by inhibition of over-augmented cartilage tissue repair, which could exhibit inhibitory properties for joint inflammation, abnormal chondrocyte clustering and osteophyte formation in OA. On the other hand, SOCS3 might reduce chondrocyte growth response, which would delay repair of subchondral cancellous bone damage in OA owing to its anti-proliferation effect. The anti-inflammation and growth inhibition effects exhibited by enhanced SOCS3 in OA appear to be related to its capacity to down-regulate expression levels of NF-κB and COX2.

A Case of Secondary Angiosarcoma of the Breast after Breast-conserving Surgery and Radiation: Review of Radiologic and Pathologic Findings

Angiosarcoma of the breast is a rare and potentially life-threatening disease. It can present as a palpable mass or subtle erythematous lesion, depending on the predisposing clinical factors. Erythematous skin lesions may be confused for a benign process, which may lead to a delay in diagnosis. We present a case of an 80-year-old woman who developed secondary angiosarcoma after undergoing breast-conserving therapy for Stage IA breast cancer. In this article, we review our experience with a case of secondary angiosarcoma of the breast and discuss the presentation, evaluation, and treatment of this disease. This case demonstrates the importance of vigilance regarding erythematous or papular breast lesions in the setting of prior local radiation.

Leukemia inhibitory factor is essential for subventricular zone neural stem cell and progenitor homeostasis as revealed by a novel flow cytometric analysis

Stem cells rely on extracellular signals produced by the niche, which dictate their ability to self-renew, expand and differentiate. It is essential to have sensitive and reproducible methods of either quantifying or isolating these stem cells and progenitors to understand their intrinsic properties and how extrinsic signals regulate their development. However, stem cells are difficult to distinguish from multipotential progenitors, which may look and act like them. Here we define a 4-color flow cytometry panel using CD133, LeX, CD140a, NG2 to define a neural stem cell (NSC) as well as 4 classes of multipotential progenitors and 3 classes of bipotential progenitors, several of which have not been described previously. We performed gain and loss of function studies for leukemia inhibitory factor (LIF) and showed a depletion of NSCs, a subset of multipotential neural precursors and immature oligodendrocytes in LIF null mice. Gain of function studies showed that LIF increased the abundance of these precursors. Our studies also show that these NPs have differential requirements for LIF and ciliary neurotrophic factor (CNTF) and for epidermal growth factor (EGF), fibroblast growth factor (FGF-2) and platelet-derived growth factor (PDGF) for their propagation in vitro. Surprisingly, the related cytokine, CNTF, was less potent than LIF in increasing the NSCs and more potent than LIF in increasing the PDGF responsive multipotential precursors. Finally, we show that LIF increases the expression of the core transcription factors: Klf4, Fbx15, Nanog, Sox2 and c-Myc. Altogether our FACS (fluorescence-activated cell sorter) analyses reveal that the neonatal subventricular zone is far more heterogeneous than previously suspected and our studies provide new insights into the signals and mechanisms that regulate their self-renewal and proliferation.

Identification and expression analysis of components involved in rice Xa21-mediated disease resistance signalling

Rice Xa21 gene encodes a receptor-like kinase that confers broad-spectrum resistance against Xanthomonas oryzae pv. oryzae (Xoo). Recently, a number of genes involved in the Xa21-mediated disease resistance pathway have been identified. Based on our previous data and the literature, we chose 16 candidate proteins and made corresponding antibodies. Using Western blotting, we systematically investigated the expression profile of the proteins in Xa21-mediated disease resistance response. We found nine proteins with altered expression. We further compared their expression in resistance, susceptible and mock responses, and found that GST expression was up-regulated during the resistance process, indicating GST is a positive regulator in resistance responses. ATPsB expression was down-regulated during both the resistance and susceptible response processes, although it was higher in the resistance response than that in the susceptible response. The total amount of MYB, GAPDH, CatB, Trx and NB-ARC proteins was lower in the resistance than in the susceptible response, but their abundance per unit bacteria in the resistance response was still higher than in the susceptible response, suggesting that these proteins might be positive regulators in the resistance response. In addition, expression of another ERF was induced by inoculation with bacterial blight pathogen, and expression of Zf-LSD1 was activated by wounding stress alone. Interestingly, most proteins showed similar altered expression patterns in the resistance and susceptible responses, but differed to some extents, implying that both responses might share common molecular mechanisms. This study revealed evidence of resistance-related protein expression, providing a foundation for better understanding of their functions.

Al nanogrid electrode for ultraviolet detectors

Optical properties of Al nanogrids of different pitches and gaps were investigated both theoretically and experimentally. Three-dimensional finite-difference time-domain simulation predicted that surface plasmons at the air/Al interface would enhance ultraviolet transmission through the subwavelength gaps of the nanogrid, making it an effective electrode on GaN-based photodetectors to compensate for the lack of transparent electrode and high p-type doping. The predicted transmission enhancement was verified by confocal scanning optical microscopy performed at 365 nm. The quality of the nanogrids fabricated by electron-beam lithography was verified by near-field scanning optical microscopy and scanning electron microscopy. Based on the results, the pitch and gap of the nanogrids can be optimized for the best trade-off between electrical conductivity and optical transmission at different wavelengths. Based on different cutoff wavelengths, the nanogrids can also double as a filter to render photodetectors solar-blind.

WD repeat-containing protein 5, a ubiquitously expressed histone methyltransferase adaptor protein, regulates smooth muscle cell-selective gene activation through interaction with pituitary homeobox 2

WD repeat-containing protein 5 (WDR5) is a common component of mammalian mixed lineage leukemia methyltransferase family members and is important for histone H3 lysine 4 methylation (H3K4me), which has been implicated in control of activation of cell lineage genes during embryogenesis. However, WDR5 has not been considered to play a specific regulatory role in epigenetic programming of cell lineage because it is ubiquitously expressed. Previous work from our laboratory showed the appearance of histone H3K4me within smooth muscle cell (SMC)-marker gene promoters during the early stages of development of SMC from multipotential embryonic cells but did not elucidate the underlying mechanisms that mediate SMC-specific and locus-selective H3K4me. Results presented herein show that knockdown of WDR5 significantly decreased SMC-marker gene expression in cultured SMC differentiation systems and in Xenopus laevis embryos in vivo. In addition, we showed that WDR5 complexes within SMC progenitor cells contained H3K4 methyltransferase enzymatic activity and that knockdown of WDR5 selectively decreased H3K4me1 and H3K4me3 enrichment within SMC-marker gene promoter loci. Moreover, we present evidence that it is recruited to these gene promoter loci through interaction with a SMC-selective pituitary homeobox 2 (Pitx2). Taken together, studies provide evidence for a novel mechanism for epigenetic control of SMC-marker gene expression during development through interaction of WDR5, homeodomain proteins, and chromatin remodeling enzymes.

The actin associated protein palladin is important for the early smooth muscle cell differentiation

Palladin, an actin associated protein, plays a significant role in regulating cell adhesion and cell motility. Palladin is important for development, as knockdown in mice is embryonic lethal, yet its role in the development of the vasculature is unknown. We have shown that palladin is essential for the expression of smooth muscle cells (SMC) marker genes and force development in response to agonist stimulation in palladin deficient SMCs. The goal of the study was to determine the molecular mechanisms underlying palladin's ability to regulate the expression of SMC marker genes. Results showed that palladin expression was rapidly induced in an A404 cell line upon retinoic acid (RA) induced differentiation. Suppression of palladin expression with siRNAs inhibited the expression of RA induced SMC differentiation genes, SM α-actin (SMA) and SM22, whereas over-expression of palladin induced SMC gene expression. Chromatin immunoprecipitation assays provided evidence that palladin bound to SMC genes, whereas co-immunoprecipitation assays also showed binding of palladin to myocardin related transcription factors (MRTFs). Endogenous palladin was imaged in the nucleus, increased with leptomycin treatment and the carboxyl-termini of palladin co-localized with MRTFs in the nucleus. Results support a model wherein palladin contributes to SMC differentiation through regulation of CArG-SRF-MRTF dependent transcription of SMC marker genes and as previously published, also through actin dynamics. Finally, in E11.5 palladin null mouse embryos, the expression of SMA and SM22 mRNA and protein is decreased in the vessel wall. Taken together, our findings suggest that palladin plays a key role in the differentiation of SMCs in the developing vasculature.