Interface Modulation for the Heterointegration of Diamond on Si.

Along with the increasing integration density and decreased feature size of current semiconductor technology, heterointegration of the Si-based devices with diamond has acted as a promising strategy to relieve the existing heat dissipation problem. As one of the heterointegration methods, the microwave plasma chemical vapor deposition (MPCVD) method is utilized to synthesize large-scale diamond films on a Si substrate, while distinct structures appear at the Si-diamond interface. Investigation of the formation mechanisms and modulation strategies of the interface is crucial to optimize the heat dissipation behaviors. By taking advantage of electron microscopy, the formation of the epitaxial ß-SiC interlayer is found to be caused by the interaction between the anisotropically sputtered Si and the deposited amorphous carbon. Compared with the randomly oriented ß-SiC interlayer, larger diamond grain sizes can be obtained on the epitaxial ß-SiC interlayer under the same synthesis condition. Moreover, due to the competitive interfacial reactions, the epitaxial ß-SiC interlayer thickness can be reduced by increasing the CH4/H2 ratio (from 3% to 10%), while further increase in the ratio (to 20%) can lead to the broken of the epitaxial relationship. The above findings are expected to provide interfacial design strategies for multiple large-scale diamond applications.

New clues to ancient water on Itokawa.

We performed the first measurements of hydrogen isotopic composition and water content in nominally anhydrous minerals collected by the Hayabusa mission from the S-type asteroid Itokawa. The hydrogen isotopic composition (δD) of the measured pyroxene grains is -79 to -53‰, which is indistinguishable from that in chondritic meteorites, achondrites, and terrestrial rocks. Itokawa minerals contain water contents of 698 to 988 parts per million (ppm) weight, after correcting for water loss during parent body processes and impact events that elevated the temperature of the parent body. We infer that the Bulk Silicate Itokawa parent body originally had 160 to 510 ppm water. Asteroids like Itokawa that formed interior to the snow line could therefore have been a potential source of water (up to 0.5 Earth's oceans) during the formation of Earth and other terrestrial planets.

Association of Nuclear PIM1 Expression with Lymph Node Metastasis and Poor Prognosis in Patients with Lung Adenocarcinoma and Squamous Cell Carcinoma.

Increasing evidence indicates that aberrant expression of PIM1, p-STAT3 and c-MYC is involved in the pathogenesis of various solid tumors, but its prognostic value is still unclear in non-small cell lung cancer (NSCLC). Here, we sought to evaluate the expression and prognostic role of these markers in patients with lung adenocarcinoma (AD) and squamous cell carcinoma (SCC). Real time RT-PCR and Western blotting was used to analyze the mRNA and protein expression of PIM1 in NSCLC cell lines, respectively. The expression of PIM1, p-STAT3, and c-MYC was immunohistochemically tested in archival tumor samples from 194 lung AD and SCC patients. High nuclear PIM1 expression was detected in 43.3% of ADs and SCCs, and was significantly correlated with lymph node (LN) metastasis (P = 0.028) and histology (P = 0.003). High nuclear PIM1 expression (P = 0.034), locally advanced stage (P < 0.001), AD (P = 0.007) and poor pathologic differentiation (P = 0.002) were correlated with worse disease-free survival (DFS). High nuclear PIM1 expression (P = 0.009), advanced clinical stage (P < 0.001) and poor pathologic differentiation (P = 0.004) were independent unfavorable prognostic factors for overall survival (OS). High p-STAT3 expression was not associated with OS but significantly correlated with LN metastasis, while c-MYC was not significantly correlated with any clinicopathological parameter or survival. Therefore, in AD and SCC patients, nuclear PIM1 expression level is an independent factor for DFS and OS and it might serve as a predictive biomarker for outcome.

EZH2 promotes cell migration and invasion but not alters cell proliferation by suppressing E-cadherin, partly through association with MALAT-1 in pancreatic cancer.

Enhancer of zeste homolog 2 (EZH2) is an essential component of the polycomb repressive complex 2 (PRC2), which is required for epigenetic silencing of target genes, including those affecting cancer progression. Its role in pancreatic cancer remains to be clarified; therefore, we investigated the effects of aberrantly expressed EZH2 on pancreatic cancer. We found that EZH2 expression is up-regulated in pancreatic cancer tissues and positively correlated with lymph node metastasis and advanced clinical stage in pancreatic cancer patients. EZH2 knockdown in pancreatic cancer cell lines inhibited cell migration and invasion, but did not alter cell proliferation. Silencing of EZH2 also increased E-cadherin expression in vitro, and E-cadherin expression was inversely correlated with EZH2 expression in pancreatic cancer tissue samples. Patients with high EZH2 and low E-cadherin expression had the worst prognosis. RIP and ChIP assays suggest that EZH2 is recruited to the E-cadherin promoter by the long non-coding RNA, MALAT-1 (metastasis associated in lung adenocarcinoma transcript 1), where it represses E-cadherin expression. Our results show that EZH2-based therapies may be an option for the treatment of pancreatic cancer.

Peroxisome proliferator-activated receptor-γ is downregulated in ulcerative colitis and is involved in experimental colitis-associated neoplasia.

The aim of the present study was to evaluate the expression of peroxisome proliferator-activated receptor (PPAR)-γ in inflammatory bowel disease (IBD), and to also identify the association between PPAR-γ and the clinical features of patients with IBD. An azoxymethane (AOM)/dextran sodium sulfate (DSS) animal model of colitis-associated neoplasia was established to investigate the protective effect of 5-aminosalicylic acid (5-ASA) and to explore the changes in the expression of PPAR-γ during this process. A total of 66 specimens of colorectal tissue obtained from biopsy performed on IBD patients and 30 healthy control individuals were immunohistochemically stained for PPAR-γ. An AOM/DSS animal model of colitis-associated neoplasia was then established. Reverse transcription quantitative polymerase chain reaction was conducted and it was found that, compared with the control group and patients with Crohn's disease (CD), the expression of PPAR-γ in the intestinal tissue of patients with ulcerative colitis (UC) was significantly decreased (P=0.027 and 0.046, respectively). The expression of PPAR-γ was found to be negatively associated with the disease activity of UC and was not associated with the severity of disease, site of lesions or CD characteristics. Administration of 5-ASA decreased the colitis and tumor burden of colons. The expression level of PPAR-γ in the intestinal tissue was also increased in the AOM/DSS/5-ASA group compared with AOM/DSS group (P<0.001). PPAR-γ is an important factor in the pathogenesis of UC and colitis-associated cancer. The present study found that 5-ASA significantly alleviates the colitis and tumor burden in a mouse model of AOM/DSS-induced colitis-associated neoplasia, and promotes the expression of PPAR-γ in the intestinal tract.

High co-expression of Sp1 and HER-2 is correlated with poor prognosis of gastric cancer patients.

The aim of this study was to investigate co-expression of HER-2 and Sp1 in gastric cancer (GC) so as to determine whether these two proteins may be correlated with poor prognosis of GC patients. We examined the HER-2 overexpression and amplification and expression levels of Sp1 in 227 GC patients using immune-histochemical staining and fluorescence in situ hybridization. Data on clinicopathological features and relevant prognostic factors in these patients were analyzed. Of the 227 gastric cancer samples, 11.89% were positive for HER-2 overexpression/amplification under the new scoring system, and the frequency of negative, weak positive and strong positive expression of Sp1 was 14.98%, 48.01% and 37.0% respectively. No statistically positive correlation was observed between the expression levels of HER-2 and Sp1 in GC tissues. HER-2 overexpression was closely correlated to the Lauren type, degree of differentiation, tumor size and lymph node metastasis, and Sp1 as well (P < 0.05). Overexpression of HER-2 and Sp1 predicted poor survival in univariate analysis as well as in a Cox proportional hazards model.

Suppressed expression of LDHB promotes pancreatic cancer progression via inducing glycolytic phenotype.

Lactate dehydrogenase B (LDHB) is widely expressed in adult somatic tissue and is one of the two subunits of lactate dehydrogenase, which is the key glycolytic enzyme and catalyzes the interconversion of pyruvate and lactate. However, the roles of LDHB in glycolysis and tumor progression were obscure in different types of cancer. Here, we determined the roles of LDHB in pancreatic cancer development and progression. We found suppressed expression of LDHB in pancreatic cancer which was due to promoter hypermethylation and deceased expression of LDHB led to glycolytic transition. Functional analysis revealed that suppressed expression of LDHB promoted pancreatic cancer cells proliferation, invasion, and migration in hypoxia. Thus, LDHB might function as a suppressor of glycolysis and suppressed pancreatic cancer progression.

Long noncoding RNA MALAT-1 enhances stem cell-like phenotypes in pancreatic cancer cells.

Cancer stem cells (CSCs) play a vital role in tumor initiation, progression, metastasis, chemoresistance, and recurrence. The mechanisms that maintain the stemness of these cells remain largely unknown. Our previous study indicated that MALAT-1 may serve as an oncogenic long noncoding RNA in pancreatic cancer by promoting epithelial-mesenchymal transition (EMT) and regulating CSCs markers expression. More significantly, there is emerging evidence that the EMT process may give rise to CSCs, or at least cells with stem cell-like properties. Therefore, we hypothesized that MALAT-1 might enhance stem cell-like phenotypes in pancreatic cancer cells. In this study, our data showed that MALAT-1 could increase the proportion of pancreatic CSCs, maintain self-renewing capacity, decrease the chemosensitivity to anticancer drugs, and accelerate tumor angiogenesis in vitro. In addition, subcutaneous nude mouse xenografts revealed that MALAT-1 could promote tumorigenicity of pancreatic cancer cells in vivo. The underlying mechanisms may involve in increased expression of self-renewal related factors Sox2. Collectively, we for the first time found the potential effects of MALAT-1 on the stem cell-like phenotypes in pancreatic cancer cells, suggesting a novel role of MALAT-1 in tumor stemness, which remains to be fully elucidated.

Biomarkers for gastric cancer: Progression in early diagnosis and prognosis (Review).

Gastric cancer is one of leading causes of cancer-related mortality worldwide and is a notable disease due to its heterogeneity. Recently, numerous studies have investigated the molecular basis of gastric cancer, involving the alteration of pathogenesis, and invasion and metastasis. With the development of modern technologies, various novel biomarkers had been identified that appear to possess diagnostic and prognostic value; therefore, the present review describes our current knowledge of biomarkers for the early diagnosis and prognosis of gastric cancer. Classic biomarkers for gastric cancer diagnosis include carcinoembryonic antigen and cancer antigen 19-9, while microRNA and DNA hypomethylation are proposed as novel biomarkers. Excluding classical biomarkers, biomarkers for determining the progression and prognosis of gastric cancer focus on targeting microRNAs, epigenetic alterations and genetic polymorphisms.

Decreased expression of histone deacetylase 10 predicts poor prognosis of gastric cancer patients.

Aberrant expression of histone deacetylase (HDACs) was associated with carcinogenesis and progression of various tumors. However, the association of HDAC10 with clinical outcomes in gastric cancer patients is unclear. Thus, the objective of the current study was to evaluate the association of expression level of HDAC10 with clinicopathologic factors and prognosis of patients with gastric cancer. The expression level of HDAC10 in 179 paraffin-embedded gastric cancer tissue specimens was examined by immunohistochemistry (IHC). As a result, we found that expression of HDAC10 in gastric cancer was significantly decreased in gastric cancer tissues as compared with adjacent tissues (51.4% vs. 87.3%, P < 0.001). HDAC10 expression was significantly correlated with gender (P = 0.023), tumor size (P = 0.015), histological grade (P = 0.009), tumor invasion (P = 0.033), lymph node metastatic status (P = 0.019) and tumor stage (P = 0.004), but not correlated with age and lauren classification (all P > 0.05). Kaplan-Meier survival curves showed that the overall survival rate was significantly lower in the patients with low expression of HDAC10 compared with those patients with high HDAC10 (P < 0.001). Moreover, multivariate analysis revealed that HDAC10 expression was an independent prognostic factor for gastric cancer patients (P = 0.001). These results suggest that HDAC10 expression could see as a prognosis marker for gastric cancer patients.

Elevated expression level of long noncoding RNA MALAT-1 facilitates cell growth, migration and invasion in pancreatic cancer.

Pancreatic cancer is one of the most aggressive solid malignancies with a dismal survival rate. Recent studies have shown that high expression levels of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript-1 (MALAT-1) correlate with several solid tumors. However, the underlying molecular mechanisms and its clinical significance in pancreatic cancer remain to be elucidated. In the present study, our results showed that MALAT-1 expression levels were upregulated in pancreatic cancer tissues compared with adjacent noncancerous controls. Consistently, higher expression level of MALAT-1 was found in all seven pancreatic cancer cell lines relative to the human pancreatic ductal epithelial cell. Further function analysis revealed that downregulation of MALAT-1 could inhibit tumor cell proliferation and decrease cell migration and invasion in vitro. The underlying mechanisms are possibly involved in inducing G2/M cell cycle arrest, promoting cell apoptosis, suppressing epithelial-mesenchymal transition and reducing cancer stem-like properties. In conclusion, this study indicated that MALAT-1 may serve as an oncogenic lncRNA that is involved in malignancy phenotypes of pancreatic cancer. Therefore, it may be used as a potential therapeutic target.

Histone deacetylase 3 promotes pancreatic cancer cell proliferation, invasion and increases drug-resistance through histone modification of P27, P53 and Bax.

Pancreatic cancer is one of the most aggressive solid malignancies with a dismal survival rate. Recent studies have shown that high expression levels of histone deacetylase 3 (HDAC3) correlate with malignant phenotype. However, the expression patterns and biological role of HDAC3 in pancreatic cancer remain unclear. In this study, our data showed that a higher level of HDAC3 protein expression was found in pancreatic cancer as compared to paired paracancerous tissues. Consistently, higher expression level of HDAC3 was found in all of the eight pancreatic cancer cell lines relative to human pancreatic ductal epithelial cells (HPDE). In addition, further function analysis revealed that HDAC3 can function as oncogenic protein, which could promote pancreatic cancer cell proliferation, migration and invasion, and may increase drug resistance. Moreover, the functional involvement of HDAC3 was partially correlated with post-induction repression of P53, P27 and Bax gene transcription, acting via H3K9 deacetylation. Taken together, our data suggest that HDAC3 participates in the pathogenesis and progression of pancreatic cancer through histone modification, which might be a pivotal epigenetic target against this devastating disease.

Research and clinical applications of molecular biomarkers in gastrointestinal carcinoma (Review).

Gastrointestinal (GI) carcinoma is a common malignant disease worldwide. Its development and progression is a multistage process involving a multifactorial etiology. Although the detailed mechanisms of the development of GI carcinoma remain controversial, the elucidation of its molecular biology over the last few years has resulted in a better perspective on its epidemiology, carcinogenesis and pathogenesis. More significantly, it is currently possible to use biological indicators or biomarkers in differential diagnosis, prognostic evaluation and specific clinical interventions. In this review, we aimed to describe the biomarkers of pathogenesis, invasion, metastasis and prognosis of GI carcinoma and discuss their potential clinical applications. The majority of these biomarkers, such as tumor-associated antigens, oncogenes and tumor suppressor genes, metastasis-associated genes, cell adhesion molecules, cytokines, growth factors and microRNAs, are currently broadly applicable.

Effects of recombinant human endostatin and its synergy with cisplatin on circulating endothelial cells and tumor vascular normalization in A549 xenograft murine model.

PURPOSE: Endostatin can normalize the tumor vasculature to some extent. However, exact length of its time window and corresponding markers for tumor vascular normalization are needed to be explored. METHODS: The A549 lung adenocarcinoma xenograft murine model was treated with recombinant human endostatin (rh-endostatin) for 14 days. Cisplatin was combined in different schedules. The effects of rh-endostatin on circulating endothelial cells (CECs) by flow cytometry, tumor vasculature and angiogenesis-related factors by confocal microscope and immunohistochemistry, and anti-tumor efficacy of cytotoxic drugs were observed. RESULTS: The activated CECs (aCECs) were increased on day 7 and decreased on day 10, and apoptotic CECs were increased on day 10. Tumor vasculature was transiently normalized with increased collagen coverage, decreased vessel permeability, intratumoral hypoxia, and microvascular density from day 7 to 10 after rh-endostatin administration. Extracellular matrix metalloproteinase inducer, vascular endothelial growth factor, matrix metalloproteinase (MMP)-2, and MMP-9 were transiently decreased by rh-endostatin from day 4 to 10, whereas the opposite effects were observed with tissue inhibitors of matrix metalloproteinase (TIMP)-1 and TIMP-2. The maximal anti-tumor effects of cisplatin were observed on administration from day 5 to 9 after rh-endostatin initial administration. CONCLUSIONS: Rh-endostatin could transiently normalize tumor vasculature, probably via regulation of both pro- and anti-angiogenesis factors. The synergistic efficacy of anti-angiogenesis and chemotherapy was found during "the normalization window". CEC could be a feasible blood biomarker for defining "vascular normalization window" and providing the evidence to make an optimizing combination therapeutic schedule in human tumor.

Stable knockdown of MYCN by lentivirus-based RNAi inhibits human neuroblastoma cells growth in vitro and in vivo.

Neuroblastoma is the most common childhood solid tumor, yet current treatment approaches have not been able to effectively control this cancer. Amplification and overexpression of MYCN have been shown to be closely related with high risk and poor prognosis in neuroblastoma. This suggests that MYCN is an important target for the antitumor therapy. Recently, vector-based RNA interference (RNAi) systems have been successfully used to eliminate gene expression, but knockdown of MYCN by vector-based RNAi as a therapeutic model for neuroblastoma has not been fully established. In this study, we used a lentivirus vector-based RNAi approach which expresses short hairpin RNA (shRNA) to knockdown MYCN in neuroblastoma cell lines IMR-32 and LAN-1. Western blotting analysis showed that expressions of MYCN were efficiently downregulated after infection with MYCN shRNA expression vector. The stable suppression of MYCN expression induced differentiation and apoptosis in neuroblastoma cell lines. Furthermore, we demonstrated that these changes were associated with caspase-3 activation, p27 upregulation as well as Bcl-2 and MDM2 downregulation. Finally, we demonstrated that downregulation of MYCN expression significantly reduced colony formation in vitro and tumor growth in nude mice. Our data indicate that lentivirus vector-mediated silencing of MYCN in neuroblastoma cells could efficiently and significantly inhibit tumor growth both in vitro and in vivo. Therefore we demonstrate the therapeutic potential of lentivirus-delivered shRNA as a novel approach for treatment of neuroblastoma and other malignant tumors with MYCN overexpression.

[Efficacy of endostar combined with chemotherapy in multi-cycle treatment of patients with advanced non-small cell lung cancer].

OBJECTIVE: To observe the correlation between long term efficacy/safety and treatment cycles of rh-endostatin (endostar) combined with TP (paclitaxel plus cisplatin/carboplatin) or NP (navelbine plus cisplatin/carboplatin) regimens in patients with advanced non-small cell lung cancer (NSCLC). METHODS: Twenty-five patients with advanced NSCLC confirmed by histopathology and/or cytology were enrolled in this study. Twenty-one patients underwent endostar combined with NP regimen and other four patients underwent endostar combined with TP regimen (all repeated 21 days) treatment. The therapeutic effects, quality of life (QOL) and adverse effects were evaluated according to RECIST criteria, Karnofsky performance scores and WHO grading of adverse effects, respectively. Our intention was to make knowledge of the therapeutic effects, median time to progression, one-year survival rate, median overall survival and adverse reactions. The amount of circulating endothelial cells (CEC) in peripheral blood was measured by flow cytometry. RESULTS: All the 25 patients were evaluable for efficacy and safety. They were comprised of 5 cases of PR, 14 cases of SD and 6 cases of PD. Of the 25 cases, RR was obtained in 5 cases (20.0%), CBR in 19 cases (76.0%), mTTP was 8 months and mOS was 19 months. Of the 14 patients with short treatment cycles (< 4), PR was obtained in 2 cases, SD in 6 cases and PD in 6 cases, RR was 14.3%. Of the 8 patients who obtained PR or SD, the median TTP was 6 months and median overall survival was 18 months. Of the 11 patients with long treatment cycles (≥ 4), PR was obtained in 3 cases, SD in 8 cases, RR was 27.3%, mTTP was 17 months and mOS was 26 months. After treatment, the amount of activated CECs was increased by (293 ± 12)/10(5) in patients with short treatment cycles, and decreased by (243 ± 181)/10(5) in patients with long treatment cycles. A positive correlation was found between the changes of activated CECs after therapy, time to progression (TTP) and treatment cycles (r = 0.970, P = 0.001; r = 0.829, P = 0.042, respectively). The quality of life (QOL) was improved in 12 cases (48.0%), stable in 10 cases (40.0%), and decreased in 3 cases (12.0%). Grade 3 and 4 toxicities were mainly related with chemotherapeutics, including neutropenia in 4 cases (16.0%), vomiting in 3 cases (12.0%) and arrhythmia in 1 case. No hypertension was observed. All the adverse reactions did not affect the following treatment, and there was no significant difference in incidence rate of grade 3 and 4 adverse events between the patients treated with long-term and short-term cycles. CONCLUSIONS: Endostar combined with TP or NP regimen chemotherapy is effective and safe in the treatment of advanced NSCLC, especially in patients with long term treatment cycles which can effectively prolong TTP and reach long term survival, but not increase adverse events. The QOL of patients can be improved or remain stable. The changes of CECs may be used as a useful maker in predicting the efficacy of the combination treatment.

Correlation of activated STAT3 expression with clinicopathologic features in lung adenocarcinoma and squamous cell carcinoma.

BACKGROUND AND OBJECTIVE: Signal transducer and activator of transcription (STAT) 3, a member of the STAT family of transcription factors in the Janus kinase (JAK)/STAT signaling pathway, is involved in cell proliferation and apoptosis. STAT3 is activated through phosphorylation (p-STAT3) and is highly expressed in many malignancies. The aims of the present study were to evaluate STAT3 activation (p-STAT3 protein levels) in lung adenocarcinoma and squamous cell carcinoma, and to investigate its correlation with clinicopathologic features of these malignancies. METHODS: Expression of p-STAT3 was detected by immunohistochemistry in tissue from 127 lung carcinomas (100 adenocarcinomas and 27 squamous cell carcinomas) and 56 normal lungs. Genomic DNA was extracted from frozen patient tissue samples, and key epidermal growth factor receptor (EGFR) mutation sites in exons 18 through 21 of the EGFR gene were amplified and sequenced. RESULTS: On the basis of the intensity and percentage of p-STAT3 immunoreactivity, samples were divided into negative and positive p-STAT3 expression groups. 103 of these 183 samples (56.3%) showed immunoreactivity for p-STAT3, and this frequency was significantly increased in carcinoma tissue compared with normal tissue (p = 0.001). Positive p-STAT3 expression was detected in 82 of the 127 carcinomas (64.6%) but in only 21 of the 56 normal tissue samples (37.5%). Among the 127 cases of non-small cell lung cancer, p-STAT3 immunoreactivity was significantly correlated with sex (p = 0.004), smoking history (p = 0.006), EGFR mutation status (p = 0.003), clinical stage (p = 0.034), and lymph node metastasis (p = 0.009). CONCLUSION: Our results suggest that p-STAT3 is an important factor during carcinogenesis and metastasis of lung carcinoma, and its relationship to EGFR mutation status may provide potential targeting opportunities in future therapies.

[Clinical characteristics and prognosis of large cell lung cancer].

OBJECTIVE: The aim of this study was to explore the clinical characteristics and analyze the prognostic factors of large cell lung cancer (LCLC). METHODS: The clinical data of 111 LCLC cases were collected and retrospectively analyzed. The prognostic factors were evaluated by univariate and multivariate analyses. RESULTS: Among the 111 cases, the lesions were in the right lung of 53 patients and 26 of them were located in the superior lobe. The lesions were in the left lung of 58 cases, and 35 of them were in the superior lobe. The lesions were presented as central in 36 cases and peripheral in 75 cases, with a mean diameter of 5.3 cm. All the 111 patients were diagnosed as stage I in 38 cases, stage II in 11 cases, stage III in 45 and stage IV in 17 cases. 60 patients had lymph node metastasis and 17 cases had distant metastasis. The overall 1-, 3- and 5-year survival rates of the LCLC were 54.7%, 30.9% and 20.6%, respectively. Cox univariate analysis revealed that TNM stage (P = 0.000), lymph node metastasis (P = 0.000) and M stage (P = 0.000) are prognostic factors. Cox multivariate analysis indicated that TNM stage (P = 0.000) is an independent prognostic factor. CONCLUSION: The prognosis of LCLC is worse than other types of non-small cell lung cancer. Complete surgical resection remains the main therapeutic approach. TNM stage is an independent prognostic factor.